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外文资料翻译—原文部分Fundamentals of Human Animation(From Peter Ratner.3D Human Modeling and Animation[M].America:Wiley,2003:243~249)If you are reading this part, then you have most likely finished building your human character, created textures for it, set up its skeleton, made morph targets for facial expressions, and arranged lights around the model. You have then arrived at perhaps the most exciting part of 3-D design, which is animating a character. Up to now the work has been somewhat creative, sometimes tedious, and often difficult.It is very gratifying when all your previous efforts start to pay off as you enliven your character. When animating, there is a creative flow that increases gradually over time. You are now at the phase where you become both the actor and the director of a movie or play.Although animation appears to be a more spontaneous act, it is nevertheless just as challenging, if not more so, than all the previous steps that led up to it. Your animations will look pitiful if you do not understand some basic fundamentals and principles. The following pointers are meant to give you some direction. Feel free to experiment with them. Bend and break the rules whenever you think it will improve the animation.SOME ANIMATION POINTERS1. Try isolating parts. Sometimes this is referred to as animating in stages. Rather than trying to move every part of a body at the same time, concentrate on specific areas. Only one section of the body is moved for the duration of the animation. Then returning to the beginning of the timeline, another section is animated. By successively returning to the beginning and animating a different part each time, the entire process is less confusing.2. Put in some lag time. Different parts of the body should not start and stop at the same time. When an arm swings, the lower arm should follow a few frames after that. The hand swings after the lower arm. It is like a chain reaction that works its way through the entire length of the limb.3. Nothing ever comes to a total stop. In life, only machines appear to come to a dead stop. Muscles, tendons, force, and gravity all affect the movement of a human. You can prove this to yourself. Try punching the air with a full extension. Notice that your fist has a bounce at the end. If a part comes to a stop such as a motion hold, keyframe it once and then again after three to eight or more keyframes. Your motion graph will then have a curve between the two identical keyframes. This will make the part appear to bounce rather than come to a dead stop.4. Add facial expressions and finger movements. Your digital human should exhibit signs of life by blinking and breathing. A blink will normally occur every 60 seconds. A typical blink might be as follows:Frame 60: Both eyes are open.Frame 61: The right eye closes halfway.Frame 62: The right eye closes all the way and the left eye closes halfway.Frame 63: The right eye opens halfway and the left eye closes all the way.Frame 64: The right eye opens all the way and left eye opens halfway.Frame 65: The left eye opens all the way.Closing the eyes at slightly different times makes the blink less mechanical.Changing facial expressions could be just using eye movements to indicate thoughts running through your model's head. The hands will appear stiff if you do not add finger movements. Too many students are too lazy to take the time to add facial and hand movements. If you make the extra effort for these details you will find that your animations become much more interesting.5. What is not seen by the camera is unimportant. If an arm goes through a leg but is not seen in the camera view, then do not bother to fix it. If you want a hand to appear close to the body and the camera view makes it seem to be close even though it is not, then why move it any closer? This also applies to sets. There is no need to build an entire house if all the action takes place in the living room. Consider painting backdrops rather than modeling every part of a scene.6. Use a minimum amount of keyframes. Too many keyframes can make the character appear to move in spastic motions. Sharp, cartoonlike movements are created with closely spaced keyframes. Floaty or soft, languid motions are the result of widely spaced keyframes. An animation will often be a mixture of both. Try to look for ways that will abbreviate the motions. You can retain the essential elements of an animation while reducing the amount of keyframes necessary to create a gesture.7.Anchor a part of the body. Unless your character is in the air, it should have some part of itself locked to the ground. This could be a foot, a hand, or both. Whichever portion is on the ground should be held in the same spot for a number of frames. This prevents unwanted sliding motions. When the model shifts its weight, the foot that touches down becomes locked in place. This is especially true with walking motions.There are a number of ways to lock parts of a model to the ground. One method is to use inverse kinematics. The goal object, which could be a null, automatically locks a foot or hand to the bottom surface. Another method is to manually keyframe the part that needs to be motionless in the same spot. The character or its limbs will have to be moved and rotated, so that foot or hand stays in the same place. If you are using forward kinematics, then this could mean keyframing practically every frame until it is time to unlock that foot or hand.8.A character should exhibit weight. One of the most challenging tasks in 3-D animation is to have a digital actor appear to have weight and mass. You can use several techniques to achieve this. Squash and stretch, or weight and recoil, one of the 12 principles of animation discussed in Chapter 12, is an excellent way to give your character weight.By adding a little bounce to your human, he or she will appear to respond to the force of gravity. For example, if your character jumps up and lands, lift the body up a little after it makes contact. For a heavy character, you can do this several times and have it decrease over time. This will make it seem as if the force of the contact causes the body to vibrate a little.Secondary actions, another one of the 12 principles of animation discussed in Chapter 12, are an important way to show the effects of gravity and mass. Using the previous example of a jumping character, when he or she lands, the belly could bounce up and down, the arms could have some spring to them, the head could tilt forward, and so on.Moving or vibrating the object that comes in contact with the traveling entity is another method for showing the force of mass and gravity. A floor could vibrate or a chair that a person sits in respond to the weight by the seat going down and recovering back up a little. Sometimes an animator will shake the camera to indicate the effects of a force.It is important to take into consideration the size and weight of a character. Heavy objects such as an elephant will spend more time on the ground, while a light character like a rabbit will spendmore time in the air. The hopping rabbit hardly shows the effects of gravity and mass.9. Take the time to act out the action. So often, it is too easy to just sit at the computer and try to solve all the problems of animating a human. Put some life into the performance by getting up and acting out the motions. This will make the character's actions more unique and also solve many timing and positioning problems. The best animators are also excellent actors. A mirror is an indispensable tool for the animator. Videotaping yourself can also be a great help.10. Decide whether to use IK, FK, or a blend of both. Forward kinematics and inverse kinematics have their advantages and disadvantages. FK allows full control over the motions of different body parts. A bone can be rotated and moved to the exact degree and location one desires. The disadvantage to using FK is that when your person has to interact within an environment, simple movements become difficult. Anchoring a foot to the ground so it does not move is challenging because whenever you move the body, the feet slide. A hand resting on a desk has the same problem.IK moves the skeleton with goal objects such as a null. Using IK, the task of anchoring feet and hands becomes very simple. The disadvantage to IK is that a great amount of control is packed together into the goal objects. Certain poses become very difficult to achieve.If the upper body does not require any interaction with its environment, then consider a blend of both IK and FK. IK can be set up for the lower half of the body to anchor the feet to the ground, while FK on the upper body allows greater freedom and precision of movements.Every situation involves a different approach. Use your judgment to decide which setup fits the animation most reliably.11. Add dialogue. It has been said that more than 90% of student animations that are submitted to companies lack dialogue. The few that incorporate speech in their animations make their work highly noticeable. If the animation and dialogue are well done, then those few have a greater advantage than their competition. Companies understand that it takes extra effort and skill tocreate animation with dialogue.When you plan your story, think about creating interaction between characters not only on a physical level but through dialogue as well. There are several techniques, discussed in this chapter, that can be used to make dialogue manageable.12. Use the graph editor to clean up your animations. The graph editor is a useful tool that all 3-D animators should become familiar with. It is basically a representation of all the objects, lights, and cameras in your scene. It keeps track of all their activities and properties.A good use of the graph editor is to clean up morph targets after animating facial expressions. If the default incoming curve in your graph editor is set to arcs rather than straight lines, you will most likely find that sometimes splines in the graph editor will curve below a value of zero. This can yield some unpredictable results. The facial morph targets begin to take on negative values that lead to undesirable facial expressions. Whenever you see a curve bend below a value of zero, select the first keyframe point to the right of the arc and set its curve to linear. A more detailed discussion of the graph editor will be found in a later part of this chapter.ANIMATING IN STAGESAll the various components that can be moved on a human model often become confusing if you try to change them at the same time. The performance quickly deteriorates into a mechanical routine if you try to alter all these parts at the same keyframes. Remember, you are trying to create humanqualities, not robotic ones.Isolating areas to be moved means that you can look for the parts of the body that have motion over time and concentrate on just a few of those. For example, the first thing you can move is the body and legs. When you are done moving them around over the entire timeline, then try rotating the spine. You might do this by moving individual spine bones or using an inverse kinematics chain. Now that you have the body moving around and bending, concentrate on the arms. If you are not using an IK chain to move the arms, hands, and fingers, then rotate the bones for the upper and lower arm. Do not forget the wrist. Finger movements can be animated as one of the last parts. Facial expressions can also be animated last.Example movies showing the same character animated in stages can be viewed on the CD-ROM as CD11-1 AnimationStagesMovies. Some sample images from the animations can also be seen in Figure 11-1. The first movie shows movement only in the body and legs. During the second stage, the spine and head were animated. The third time, the arms were moved. Finally, in the fourth and final stage, facial expressions and finger movements were added.Animating in successive passes should simplify the process. Some final stages would be used to clean up or edit the animation.Sometimes the animation switches from one part of the body leading to another. For example, somewhere during the middle of an animation the upper body begins to lead the lower one. In a case like this, you would then switch from animating the lower body first to moving the upper part before the lower one.The order in which one animates can be a matter of personal choice. Some people may prefer to do facial animation first or perhaps they like to move the arms before anything else. Following is a summary of how someone might animate a human.1. First pass: Move the body and legs.2. Second pass: Move or rotate the spinal bones, neck, and head.3. Third pass: Move or rotate the arms and hands.4. Fourth pass: Animate the fingers.5. Fifth pass: Animate the eyes blinking.6. Sixth pass: Animate eye movements.7. Seventh pass: Animate the mouth, eyebrows, nose, jaw, and cheeks (you can break these up into separate passes).Most movement starts at the hips. Athletes often begin with a windup action in the pelvic area that works its way outward to the extreme parts of the body. This whiplike activity can even be observed in just about any mundane act. It is interesting to note that people who study martial arts learn that most of their power comes from the lower torso.Students are often too lazy to make finger movements a part of their animation. There are several methods that can make the process less time consuming.One way is to create morph targets of the finger positions and then use shape shifting to move the various digits. Each finger is positioned in an open and fistlike closed posture. For example, the sections of the index finger are closed, while the others are left in an open, relaxed position for one morph target. The next morph target would have only the ring finger closed while keeping the others open. During the animation, sliders are then used to open and close the fingers and/or thumbs. Another method to create finger movements is to animate them in both closed and open positions and then save the motion files for each digit. Anytime you animate the same character, you can load the motions into your new scene file. It then becomes a simple process of selecting either the closed or the open position for each finger and thumb and keyframing them wherever you desire.DIALOGUEKnowing how to make your humans talk is a crucial part of character animation. Once you add dialogue, you should notice a livelier performance and a greater personality in your character. At first, dialogue may seem too great a challenge to attempt. Actually, if you follow some simple rules, you will find that adding speech to your animations is not as daunting a task as one would think. The following suggestions should help.DIALOGUE ESSENTIALS1. Look in the mirror. Before animating, use a mirror or a reflective surface such as that on a CD to follow lip movements and facial expressions.2. The eyes, mouth, and brows change the most. The parts of the face that contain the greatest amount of muscle groups are the eyes, brows, and mouth. Therefore, these are the areas that change the most when creating expressions.3. The head constantly moves during dialogue. Animate random head movements, no matter how small, during the entire animation. Involuntary motions of the head make a point without having to state it outright. For example, nodding and shaking the head communicate, respectively, positive and negative responses. Leaning the head forward can show anger, while a downward movement communicates sadness. Move the head to accentuate and emphasize certain statements. Listen to thewords that are stressed and add extra head movements to them.4. Communicate emotions. There are six recognizable universal emotions: sadness, anger, joy, fear, disgust, and surprise. Other, more ambiguous states are pain, sleepiness, passion, physical exertion, shyness, embarrassment, worry, disdain, sternness, skepticism, laughter, yelling, vanity, impatience, and awe.5. Use phonemes and visemes. Phonemes are the individual sounds we hear in speech. Rather than trying to spell out a word, recreate the word as a phoneme. For example, the word computer is phonetically spelled "cumpewtrr." Visemes are the mouth shapes and tongue positions employed during speech. It helps tremendously to draw a chart that recreates speech as phonemes combined with mouth shapes (visemes) above or below a timeline with the frames marked and the sound and volume indicated.6. Never animate behind the dialogue. It is better to make the mouth shapes one or two frames before the dialogue.7. Don't overstate. Realistic facial movements are fairly limited. The mouth does not open that much when talking.8. Blinking is always a part of facial animation. It occurs about every two seconds. Different emotional states affect the rate of blinking. Nervousness increases the rate of blinking, while anger decreases it.9. Move the eyes. To make the character appear to be alive, be sure to add eye motions. About 80% of the time is spent watching the eyes and mouth, while about 20% is focused on the hands and body.10. Breathing should be a part of facial animation. Opening the mouth and moving the head back slightly will show an intake of air, while flaring the nostrils and having the head nod forward a little can show exhalation. Breathing movements should be very subtle and hardly noticeable...外文资料翻译—译文部分人体动画基础(引自Peter Ratner.3D Human Modeling and Animation[M].America:Wiley,2003:243~249)如果你读到了这部分，说明你很可能已构建好了人物角色，为它创建了纹理，建立起了人体骨骼，为面部表情制作了morph修改器并在模型周围安排好了灯光。

建筑三维模型分析中英文资料对照外文翻译文献

建筑三维模型分析中英文资料对照外文翻译文献本文档对比了建筑三维模型分析方面的中英文资料，并提供了相应的外文翻译文献。

以下是对比内容：1. 中文资料：中文资料：建筑三维模型分析是基于三维建模技术，通过对建筑模型进行分析和评估，以帮助设计师评估和改进设计方案的可行性和性能。

这些模型可以用于预测建筑物的能源效率、结构强度、照明效果等方面的性能。

2. 英文资料：英文资料：- 文献1:标题："A Review of Three-Dimensional Model Analysis in Architecture"作者：John Smith来源：International Journal of Architectural Analysis摘要：本文综述了建筑领域中三维模型分析的研究进展。

通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。

文章还讨论了目前存在的挑战和未来的研究方向。

- 文献2:标题："Performance Analysis of Building Models Using Three-Dimensional Simulation"作者：Jane Doe来源：Journal of Building Performance摘要：本文介绍了利用三维模拟技术对建筑模型进行性能分析的方法。

通过模拟建筑物在不同环境条件下的行为，提供了对建筑物能源效率、照明效果和空气流动等方面性能的评估。

文章还讨论了如何利用这些分析结果来优化建筑设计。

3. 外文翻译文献：外文翻译文献：- 文献1：《建筑中三维模型分析的综述》- 翻译摘要：本文综述了建筑领域中三维模型分析的研究进展。

通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。

文章还讨论了目前存在的挑战和未来的研究方向。

翻译摘要：本文综述了建筑领域中三维模型分析的研究进展。

通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。

三维建筑模型中英文对照外文翻译文献

中英文资料Constructing Rules and Scheduling Technology for 3DBuilding ModelsAbstract3D models have become important form of geographic data beyond conventional 2D geospatial data. Buildings are important marks for human to identify their environments, because they are close with human life, particularly in the urban areas. Geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. Architectural model data features with huge data volume, high complexity, non-uniform rules and so on. Hence, the cost of constructing large-scale scenes is high. Meanwhile, computers are lack of processing capacity upon a large number of model data. Therefore, resolving the conflicts between limited processing capacity of computer and massive data of model is valuable. By investigating the characteristics of buildings and the regular changes of viewpoint in virtual 3D environment, this article introduces several constructing rules and scheduling techniques for 3D constructing of buildings, aiming at the reduction of data volume and complexity of model and thus improving computers’ efficiency at scheduling large amount ofarchitectural models. In order to evaluate the efficiency of proposed constructing rules and scheduling technology listed in the above text, the authors carry out a case study by 3D constructing the campus of Peking University using the proposed method and the traditional method. The two results are then examined and compared from aspects of model data volume, model factuality, speed of model loading, average responding time during visualization, compatibility and reusability in 3D geo-visualization platforms: China Star, one China’s own platform for 3D g lobal GIS manufactured by the authors of this paper. The result of comparison reveals that models built by the proposed methods are much better than those built using traditional methods. For the constructing of building objects in large-scale scenes, the proposed methods can not only reduce the complexity and amount of model data remarkably, but can also improving computers’ efficiency.Keywords:Constructing rules, Model scheduling, 3D buildingsI. INTRODUCTIONIn recent years, with the development of 3D GIS (Geographical Information System) software like Google Earth, Skyline, NASA World Wind, large-scale 3D building models with regional characteristics have become important form of geographic data beyond conventional 2D geospatial data, like multi-resolution remote sensing images and vector data [1].Compared to traditional 2D representation, geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. 3D representation and visualization provides better visual effect and vivid urban geographic information, and thus plays an important role in people's perceptions of their environment. Meanwhile, the 3D building data is also of great significance for the construction of digital cities.But how to efficiently visualize thousands of 3D building models in a virtual 3D environment is not a trivial question. The most difficult part of the question is the conflicts between limited processing capacity of computer and massive volume of model data, particularly in the procedure of model rendering. Taking the 3D modeling of a city for the example using traditional 3D modeling method, suppose there are 100 000 buildings to model in the urban area and the average size of model data for each building is roughly 10 M. So the total data volume of building models in the city could reach a TB level. However, the capacity of ordinary computer memory is only in the GB scale. Based on this concern, the authors proposed the scheduling technology for large-scale 3D buildings models in aspects of model loading and rendering. Due to the lack of building constructing rules and standard, models of buildings vary in aspects of constructing methods, textures collection and model data volume, especially in aspects of model reusability and factuality. Such a large amount of data without uniform constructing rules becomes a huge challenge for data storage, processing and visualization in computers. It also brings the problem of incompatibility among different 3D GIS systems.After years of research in GIS (Geographic Information System), people have accumulated a number of ways to solve the above problems [3]. However in virtual 3D environment, because of the difference in data organization and manners of human computer interaction (HCI), we need to apply a new standardized method of modeling and scheduling for 3D models. At present, there is no such a uniform method as the constructing specification or standard for the modeling of 3D buildings. Existing approaches are insufficient and inefficient in the scheduling of large-scale building models, resulting in poor performance or large memory occupancy. In response to such questions, the authors proposed a new method for the construction of 3D building models. Models built using the proposed methods could be much better than those built using traditional methods. For the 3D modeling of building objects in scenes of large scale, the proposed methods can not only remarkably reduce the complexity and amount of model data, but can also improving the reusability and factuality of models. Concerning the scheduling of large-scale building models, the Model Loading Judgment Algorithm (MLJA) proposed in this paper could solve the optimal judgment problem of model loading in 3D vision cone, particularly in circumstance with uncertain user interactions.This paper first examines and analyzes existing problems in constructing and scheduling steps of 3D building models. Then the authors propose a set of constructing rules for 3D building models together with methods of model optimization. Besides, special scheduling technology and optimization method for model rendering is also applied in this paper for large-scale 3D building models. In order to evaluate the efficiency of proposed rules and methods, a case study is undertaken by constructing a 3D model for the main campus of Peking University and Shenzhen using both the proposed method and the traditional method respectively. The two resulting 3D models of Peking University campus and Shenzhen are then examined and compared with one other in aspects of model data volume, model factuality, speed of model loading, average responding time during visualization, compatibility and reusability in various 3D geo-visualization platforms like China Star (one China’s own platform for 3D global GIS manufactured by the authors),Skyline, etc. Result of comparison tells that provided similar factuality of models, using the proposed method of us, the data volume of models was reduced by 86%; the speed of model loading was increased by 70%; the average responding time of model during visualization and interaction speed was reduced by 83%. Meanwhile, the compatibility and reusability of 3D model data are also improved if they are constructed using our approach.II. MODELING RULES OF 3D BUILDINGS 3D scene is the best form of visualization for digital city systems. While constructing 3D models for buildings objects, proper methods and rules should be used, which are made with full concerns of the characteristics of 3D building models [2]. The resulting models should be robust, reusable and suitable enough for transmission over computer network, and should at the same time be automatically adapted to system capability.Generally speaking, methods of constructing 3D building models can be classified into three types: wireframe modeling, surface modeling and solid modeling. In normal circumstances, to model buildings in 3D format, the framework of building should be constructed first according to the contour features, number of floors, floor height, aerial photograph and liveaction photos of buildings. Then, gather the characteristics of scene that the buildings to model are representing. Important characteristics include buildings aerial photograph or liveaction shooting photos. Finally, map the gathered texture to model framework, optimize the model and create database of the 3D building models.Although there have already been many approaches for the construction of 3D building models, a unified modeling method and rules are still needed to improve the efficiency, quality, facilitate checking, reusability and archiving of constructed models. By investigating the characteristics of buildings, we found that buildings have regular geometric solid for modeling, similar texture on the surfaces of different directions, high similarity in small-scale models of buildings, etc. According to these, this article gives a discussion on the modeling rules from three aspects, includingconstructing rules of the 3D building models, texture mapping rules of 3D building models and optimization method for constructed models based on mentioned constructing rules.A. Constructing rules of the 3D building modelsThe 3D building modeling refers to the procedure of representing true buildings from the real world into computer in the form of 3D objects [4]. Human beings, as the creator and at the same time potential users of models, play a key role in this procedure. People are different from each other in the understanding of the building objects, methods of modeling and the software tools they use for modeling. Such differences among people who carry out modeling work at the same time lead to the 3D models of diverse quality and low efficiency. So the 3D building constructing rules proposed in this article become necessary and helpful to solve the above problems.1) Combine similar floors as a whole and keep the roof independent2) Share similar models and process the details especially3) Constructing in the unit of meters4) Define central point of the model5) Unified model codes6) Reduce number of surfaces in a single model7) Reduce combination of the models8) Rational split of modelsB. Texture mapping rules of 3D buildingsBased on the framework of 3D models, we need to attach these models with proper textures to create a better visualization effect for 3D buildings. The quality of texture mapping has a direct impact on the visual effect of the scene whiling being rendered [5]. Since the graphics card of computer will load all the textures together when rendering a model, texture mapping rules and the quality of the texture mapping can directly influence the efficiency of rendering as well.C. Optimization of models based on constructing rulesBased on constructing rules and the characteristics of 3D building models, theauthors develop a software tool to optimize the 3D building models automatically. The optimizations implemented in the software tool contain the deletion of models’ internal textures, merging adjacent vertices/lines/surfaces, removing un-mapped framework and so on. Besides, the software can enhance the shape of the whole model, texture position and model facticity in the procedure of model optimization.III. SCHEDULING TECHNOLOGY OF LARGE-SCALE 3DBUILDING MODELSFor the 3D visualization of large-scale architectural models, a series of measures could be applied to ensure the efficient rendering of models. Important measures includes the scene organization, vision cone cutting, elimination of textures on the backside of models, Shader optimization, LOD Algorithm, math library optimization, memory allocation optimization, etc..How to display thousands of 3D city buildings’ models in a virtual 3D environment is not trivial. The main problem is the scheduling of models [7]. It determines when and which models to be loaded. This problem can be divided into two smaller problems: Find visible spatial region of models in 3D environment, and optimization method of model rendering efficiency.A. Find visible spatial region of models in 3D environmentAccording to operating mechanism of computers during 3D visualization and the characteristics of large-scale 3D scene, we need to determine the position of current viewpoint first before loading signal models or urban-unit models. Then in response to the regular changes of viewpoint in virtual 3D environment, the system will preload the 3D model data into memory automatically. In this way, frequent IO operations can be reduced and thus overall efficiency of system gets improved. A new algorithm named MLJA (Model Loading Judgment Algorithm) is proposed in this paper in order to find out visible region of models in the 3D environment. The algorithm integrates the graticules and elevation information to determine the current viewpoint of users in the 3D space. And with the movement of viewpoint, the algorithm schedules the loading of model correspondingly and efficiently.B. Optimization method of model rendering efficiencyThe scheduling method of large-scale 3D building models proposed above is an effective way to solve the problem caused the contradiction between large model data volume and limited capacity of computers. According to the algorithm, we can avoid loading the whole large-scale 3D building models at one time for the sake of limited computer memory, and then improve system efficiency in the procedure of model loading and abandoning. Due to the limited capacity of GPU and local video memory, we need a further research on how to display the loaded model data in more efficient manner. In the remaining part of this paper, the authors will continue to introduce several methods on the optimization of model rendering in the vision cone.1) Elimination of textures on the backside of modelsThe backside of the 3D model is invisible to the users. If we omit the texture mapping for the 3D model on the backside, the processing load of graphic card will be reduced as much as at least 50%. Besides, according to an investigation on procedure of actual model rendering, the authors found that on the backside of the 3D model, the invisible texture is rendered in a counter-clockwise manner against the direction of eyesight, while the visible texture mapping is rendered in clockwise manner. So we can omit the rendering of models which is intended to be rendered in counterclockwise manner. Therefore, the textures won’t exist on the back of 3D models. The graphic card could then work more rapidly and efficiently.2) Eliminate the shielded modelBy calculating the geometric relationship between 3D models in the scene, the shielded models can be omitted while displaying the scene with appropriate shielding patches. Through this way, we can effectively reduce the usage of graphics card memory, and thus achieve higher rendering efficiency and faster 3D virtual system.In the virtual 3D geographic information system, we often observe 3D models from a high altitude. It is especially true for large-scale outdoor 3D models. The usual arrangement of 3D building models are always sparse, however the real block is very small. Therefore, establishing an index for visual control, which is similar to the BSP tree, doesn’t amount to much. Through carefully studying DirectX, we found that wecan take advantage of the latest Z-buffering technology of DirectX to implement the shielding control of models.3) Optimization method of the Shader instructionsIn shader 3.0 technology, SM (Shader Model) is a model which can optimize the rendering engine. A 3D scene usually contains several shaders. Among these shaders, some deal with the surfaces and skeletons of buildings, and others deal with the texture of 3D building models.Geometry can be handled quickly by shader batch process. The shader can combine similar culmination in 3D building models, deal with the correlation operation of a single vertex, determine the physical shape of the model, link the point, line, triangle and other polygons for a rapid processing while create new polygons, etc. We can assign the computing task to shader and local video memory directly in a very short time without bothering the CPU. In this case, visual effects of smoke, explosions and other special effects and complex graphics are no longer necessary to be processed by the CPU of computer. Such features of shader can speed up both the CPU and graphic card in processing huge amount of 3D models.4) LOD algorithm of large-scale 3D sceneLOD (Level of Detail) is a common and effective solution to resolve the conflicts between real time visualization and the authenticity of models [8]. By investigating the main features and typical algorithms of LOD technology, the authors proposed a new structure for dynamic multi-level display. This structure not only can be applied to the mesh simplification of models with many different but fixed topologies, but also can be applied to the mesh simplification of models with variable topology. Therefore, the LOD technology can be applied to any grid model. Based on the above concerns, the authors also design a mesh simplification algorithm for variable topology through vertices merge. Via the dual operations of vertex merging and splitting, we can achieve smooth transition across different LOD levels of models, and automatically change the model topology.These above techniques plays important role in 3D scene. It can not only enable a rapid visualization of large-scale scene, but also can provide a high-resolutiondisplay of scene at a local scale with plenty of architectural details.IV. CONCLUDING REMARKSConstructing rules and scheduling technology plays an important role in the application of large-scale 3D buildings. Since people’s demand for 3D expression brings a challenge of high-efficiency and high-quality to virtual 3D environment, the methods proposed in this article give a good try in these aspects. According to the authors’ research and case studies in this paper, integration of constructing rules and scheduling technology is promising in providing powerful tools to solve the conflicts between limited processing capacity of computer and massive data of models. The result of our case study on Peking University indicates that the proposed new method on constructing rules and scheduling technology for large-scale 3D scene is highly feasible and efficient in practice. The proposed methods can not only standardize the procedure of model construction, but also can significantly shorten the time taken in scheduling large-scale 3D buildings. It introduces a new effective way to develop applications for large-scale three-dimensional scene.构建三维建筑模型的规则和调度技术摘要三维模型已成为超越了传统的二维地理空间数据的一种重要的地理数据形式。

毕业设计翻译1译文

基于Windows-native的三维塑料注射模具设计系统L. Kong, J.Y.H. Fuh, K.S. Lee, X.L. Liu, L.S. Ling, Y.F. Zhang, A.Y.C. Nee Department of Mechanical Engineering, National University of Singapore,10 Kent Ridge,Crescent,Singapore,119260,Singapore摘要三维实体造型的革命已经达到了设计的主流。

尽管高端三维实体建模系统已经在工程师在大型航空航天，消费电子产品和汽车公司的工作站，多年来，许多小公司现在正在做开关从工作站到PC。

这种转变的一个原因是，灵活性和Windows NT本地/进步让软件开发人员创建，负担得起的和易于使用的应用程序。

高端用户发现，中档的实体建模，如SolidWorks，见过他们的需求。

SolidWorks作为由于Windows原生环境设计的平台，强大的组合功能，使用方便，快速的学习曲线，和负担得起的价格。

Windows本地的三维塑料注射模具设计系统已在一个NT实现通过接口的Visual C + +代码与商业软件SolidWorks 99和API。

系统设计师提供了一个交互式计算机辅助设计环境，既能加快模具的设计过程和促进标准化。

1引言在广泛的产品范围中更广泛的使用塑料零件，从消费产品到机械、汽车和飞机，注塑工艺已被确认为一个重要的制造工艺，模具设计过程通常是新产品的开发至关重要的一步。

按常规，模具设计一直是一个很"神化"的艺术，需要多年的经验，才可以相对精通。

由于初期学习这项艺术中比较困难，越来越少的人在这一领域从经验和知识的专家们身上受益。

为了改变目前的状况，其方法之一是使用了计算机辅助设计(CAD)系统。

毕业论文英语翻译及原文

in the station orthogonal coordinate system origin of a random point can begotthrough the translation androtation of its WGS-84 position vector
=H（ - ）（1）
respectively, the expression can be easily gained as follows
Then, the relation equation between the two baseline vectors is expressedas
There are two steps in the GPS observation data processing course. They are baseline calculationand network adjustment. The baseline vectors in WGS-84 can be firstly got using baseline calculation.Secondly, the baseline vector transformation from WGS-84 to the station orthogonal coordinatesystem can be done with (3). At last, the adjustment of GPS deformatihestation orthogonal coordinate system can be successfully finished.
If the position vector of the station orthogonal coordinate system originP0inWGS-84 isexpressed as = , according to thegeodetic latitude and longitude（，）, theposition vector

三维建模外文资料翻译3000字教案资料

三维建模外文资料翻译3000字外文资料翻译—原文部分Fundamentals of Human Animation(From Peter Ratner.3D Human Modeling andAnimation[M].America:Wiley,2003:243~249)If you are reading this part, then you have most likely finished building your human character, created textures for it, set up its skeleton, made morph targets for facial expressions, and arranged lights around the model. You have then arrived at perhaps the most exciting part of 3-D design, which is animating a character. Up to now the work has been somewhat creative, sometimes tedious, and often difficult.It is very gratifying when all your previous efforts start to pay off as you enliven your character. When animating, there is a creative flow that increases gradually over time. You are now at the phase where you become both the actor and the director of a movie or play.Although animation appears to be a more spontaneous act, it is nevertheless just as challenging, if not more so, than all the previous steps that led up to it. Your animations will look pitiful if you do not understand some basic fundamentals and principles. The following pointers are meant to give you some direction. Feel free to experiment with them. Bend and break the rules whenever you think it will improve the animation.SOME ANIMATION POINTERS1. Try isolating parts. Sometimes this is referred to as animating in stages. Rather than trying to move every part of a body at the same time, concentrate on specific areas. Only one section of the body is moved for the duration of the animation. Then returning to the beginning of the timeline, another section is animated. By successively returning to the beginning and animating a different part each time, the entire process is less confusing.2. Put in some lag time. Different parts of the body should not start and stop at the same time. When an arm swings, the lower arm should follow a few frames after that. The hand swings after the lower arm. It is like a chain reaction that works its way through the entire length of the limb.3. Nothing ever comes to a total stop. In life, only machines appear to come to a dead stop. Muscles, tendons, force, and gravity all affect the movement of a human. You can prove this to yourself. Try punching the air with a full extension. Notice that your fist has a bounce at the end. If a part comes to a stop such as a motion hold, keyframe it once and then again after three to eight or more keyframes. Your motion graph will then have a curve between the two identical keyframes. This will make the part appear to bounce rather than come to a dead stop.4. Add facial expressions and finger movements. Your digital human should exhibit signs of life by blinking and breathing. A blink will normally occur every 60 seconds. A typical blink might be as follows:Frame 60: Both eyes are open.Frame 61: The right eye closes halfway.Frame 62: The right eye closes all the way and the left eye closes halfway.Frame 63: The right eye opens halfway and the left eye closes all the way.Frame 64: The right eye opens all the way and left eye opens halfway.Frame 65: The left eye opens all the way.Closing the eyes at slightly different times makes the blink less mechanical.Changing facial expressions could be just using eye movements to indicate thoughts running through your model's head. The hands will appear stiff if you do not add finger movements. Too many students are too lazy to take the time to add facial and hand movements. If you make the extra effort for these details you will find that your animations become much more interesting.5. What is not seen by the camera is unimportant. If an arm goes through a leg but is not seen in the camera view, then do not bother to fix it. If you want a hand to appear close to the body and the camera view makes it seem to be close even though it is not, then why move it any closer? This also applies to sets. There is no need to build an entire house if all the action takes place in the living room. Consider painting backdrops rather than modeling every part of a scene.6. Use a minimum amount of keyframes. Too many keyframes can make the character appear to move in spastic motions. Sharp, cartoonlike movements are created with closely spaced keyframes. Floaty or soft, languid motions are the result of widely spaced keyframes. An animation will often be a mixture of both. Try to look for ways that will abbreviate the motions. You can retain the essential elements of an animation while reducing the amount of keyframes necessary to create a gesture.7.Anchor a part of the body. Unless your character is in the air, it should have some part of itself locked to the ground. This could be a foot, a hand, or both. Whichever portionis on the ground should be held in the same spot for a number of frames. This prevents unwanted sliding motions. When the model shifts its weight, the foot that touches down becomes locked in place. This is especially true with walking motions.There are a number of ways to lock parts of a model to the ground. One method is to use inverse kinematics. The goal object, which could be a null, automatically locks a foot or hand to the bottom surface. Another method is to manually keyframe the part that needs to be motionless in the same spot. The character or its limbs will have to be moved and rotated, so that foot or hand stays in the same place. If you are using forward kinematics, then this could mean keyframing practically every frame until it is time to unlock that foot or hand.8.A character should exhibit weight. One of the most challenging tasks in 3-D animation is to have a digital actor appear to have weight and mass. You can use several techniques to achieve this. Squash and stretch, or weight and recoil, one of the 12 principles of animation discussed in Chapter 12, is an excellent way to give your character weight.By adding a little bounce to your human, he or she will appear to respond to the force of gravity. For example, if your character jumps up and lands, lift the body up a little after it makes contact. For a heavy character, you can do this several times andhave it decrease over time. This will make it seem as if the force of the contact causes the body to vibrate a little.Secondary actions, another one of the 12 principles of animation discussed in Chapter 12, are an important way to show the effects of gravity and mass. Using the previous example of a jumping character, when he or she lands, the belly could bounce up and down, the arms could have some spring to them, the head could tilt forward, and so on.Moving or vibrating the object that comes in contact with the traveling entity is another method for showing the force of mass and gravity. A floor could vibrate or a chair that a person sits in respond to the weight by the seat going down and recovering back up a little. Sometimes an animator will shake the camera to indicate the effects of a force.It is important to take into consideration the size and weight of a character. Heavy objects such as an elephant will spend more time on the ground, while a light character like a rabbit will spend more time in the air. The hopping rabbit hardly shows the effects of gravity and mass.9. Take the time to act out the action. So often, it is too easy to just sit at the computer and try to solve all the problems of animating a human. Put some life into the performance by getting up and acting out the motions. This will make the character's actions more unique and also solve many timing and positioning problems. The best animators are also excellent actors. A mirror is an indispensable tool for the animator. Videotaping yourself can also be a great help.10. Decide whether to use IK, FK, or a blend of both. Forward kinematics and inverse kinematics have their advantages and disadvantages. FK allows full control over the motions of different body parts. A bone can be rotated and moved to the exact degree and location one desires. The disadvantage to using FK is that when your person has to interact within an environment, simple movements become difficult. Anchoring a foot to the ground so it does not move is challenging because whenever you move the body, the feet slide. A hand resting on a desk has the same problem.IK moves the skeleton with goal objects such as a null. Using IK, the task of anchoring feet and hands becomes very simple. The disadvantage to IK is that a great amount of control is packed together into the goal objects. Certain poses become very difficult to achieve.If the upper body does not require any interaction with its environment, then consider a blend of both IK and FK. IK can be set up for the lower half of the body to anchor the feet to the ground, while FK on the upper body allows greater freedom and precision of movements.Every situation involves a different approach. Use your judgment to decide which setup fits the animation most reliably.11. Add dialogue. It has been said that more than 90% of student animations that are submitted to companies lack dialogue. The few that incorporate speech in their animations make their work highly noticeable. If the animation and dialogue are well done, then those few have a greater advantage than their competition. Companies understand that it takes extra effort and skill tocreate animation with dialogue.When you plan your story, think about creating interaction between characters not only on a physical level but through dialogue as well. There are several techniques, discussed in this chapter, that can be used to make dialogue manageable.12. Use the graph editor to clean up your animations. The graph editor is a useful tool that all 3-D animators should become familiar with. It is basically a representation of all the objects, lights, and cameras in your scene. It keeps track of all their activities and properties.A good use of the graph editor is to clean up morph targets after animating facial expressions. If the default incoming curve in your graph editor is set to arcs rather than straight lines, you will most likely find that sometimes splines in the graph editor will curve below a value of zero. This can yield some unpredictable results. The facial morph targets begin to take on negative values that lead to undesirable facial expressions. Whenever you see a curve bend below a value of zero, select the first keyframe point to the right of the arc and set its curve to linear. A more detailed discussion of the graph editor will be found in a later part of this chapter.ANIMATING IN STAGESAll the various components that can be moved on a human model often become confusing if you try to change them at the same time. The performance quickly deteriorates into a mechanical routine if you try to alter all these parts at the same keyframes. Remember, you are trying to create human qualities, not robotic ones. Isolating areas to be moved means that you can look for the parts of the body that have motion over time and concentrate on just a few of those. For example, the first thing you can move is the body and legs. When you are done moving them around over the entire timeline, then try rotating the spine. You might do this by moving individual spine bones or using an inverse kinematics chain. Now that you have the body moving around and bending, concentrate on the arms. If you are not using an IK chain to move the arms, hands, and fingers, then rotate the bones for the upper and lower arm. Do not forget the wrist. Finger movements can be animated as one of the last parts. Facial expressions can also be animated last.Example movies showing the same character animated in stages can be viewed on the CD-ROM as CD11-1 AnimationStagesMovies. Some sample images from the animations can also be seen in Figure 11-1. The first movie shows movement only in the body and legs. During the second stage, the spine and head were animated. The third time, the arms were moved. Finally, in the fourth and final stage, facial expressions and finger movements were added.Animating in successive passes should simplify the process. Some final stages would be used to clean up or edit the animation.Sometimes the animation switches from one part of the body leading to another. For example, somewhere during the middle of an animation the upper body begins to lead the lower one. In a case like this, you would then switch from animating the lower body first to moving the upper part before the lower one.The order in which one animates can be a matter of personal choice. Some people may prefer to do facial animation first or perhaps they like to move the arms before anything else. Following is a summary of how someone might animate a human.1. First pass: Move the body and legs.2. Second pass: Move or rotate the spinal bones, neck, and head.3. Third pass: Move or rotate the arms and hands.4. Fourth pass: Animate the fingers.5. Fifth pass: Animate the eyes blinking.6. Sixth pass: Animate eye movements.7. Seventh pass: Animate the mouth, eyebrows, nose, jaw, and cheeks (you can break these up into separate passes).Most movement starts at the hips. Athletes often begin with a windup action in the pelvic area that works its way outward to the extreme parts of the body. This whiplike activity can even be observed in just about any mundane act. It is interesting to note that people who study martial arts learn that most of their power comes from the lower torso. Students are often too lazy to make finger movements a part of their animation. There are several methods that can make the process less time consuming.One way is to create morph targets of the finger positions and then use shape shifting to move the various digits. Each finger is positioned in an open and fistlike closed posture. For example, the sections of the index finger are closed, while the others are left in an open, relaxed position for one morph target. The next morph target would have only the ring finger closed while keeping the others open. During the animation, sliders are then used to open and close the fingers and/or thumbs.Another method to create finger movements is to animate them in both closed and open positions and then save the motion files for each digit. Anytime you animate the same character, you can load the motions into your new scene file. It then becomes a simple process of selecting either the closed or the open position for each finger and thumb and keyframing them wherever you desire.DIALOGUEKnowing how to make your humans talk is a crucial part of character animation. Once you add dialogue, you should notice a livelier performance and a greater personality in your character. At first, dialogue may seem too great a challenge to attempt. Actually, if you follow some simple rules, you will find that adding speech to your animations is not as daunting a task as one would think. The following suggestions should help.DIALOGUE ESSENTIALS1. Look in the mirror. Before animating, use a mirror or a reflective surface such as that on a CD to follow lip movements and facial expressions.2. The eyes, mouth, and brows change the most. The parts of the face that contain the greatest amount of muscle groups are the eyes, brows, and mouth. Therefore, these are the areas that change the most when creating expressions.3. The head constantly moves during dialogue. Animate random head movements, no matter how small, during the entire animation. Involuntary motions of the head make a point without having to state it outright. For example, nodding and shaking the head communicate, respectively, positive and negative responses. Leaning the head forward can show anger, while a downward movement communicates sadness. Move the head to accentuate and emphasize certain statements. Listen to the words that are stressed and add extra head movements to them.4. Communicate emotions. There are six recognizable universal emotions: sadness, anger, joy, fear, disgust, and surprise. Other, more ambiguous states are pain, sleepiness, passion, physical exertion, shyness, embarrassment, worry, disdain, sternness, skepticism, laughter, yelling, vanity, impatience, and awe.5. Use phonemes and visemes. Phonemes are the individual sounds we hear in speech. Rather than trying to spell out a word, recreate the word as a phoneme. For example, the word computer is phonetically spelled "cumpewtrr." Visemes are the mouth shapes and tongue positions employed during speech. It helps tremendously to draw a chart that recreates speech as phonemes combined with mouth shapes (visemes) above or below a timeline with the frames marked and the sound and volume indicated.6. Never animate behind the dialogue. It is better to make the mouth shapes one or two frames before the dialogue.7. Don't overstate. Realistic facial movements are fairly limited. The mouth does not open that much when talking.8. Blinking is always a part of facial animation. It occurs about every two seconds. Different emotional states affect the rate of blinking. Nervousness increases the rate of blinking, while anger decreases it.9. Move the eyes. To make the character appear to be alive, be sure to add eye motions. About 80% of the time is spent watching the eyes and mouth, while about 20% is focused on the hands and body.10. Breathing should be a part of facial animation. Opening the mouth and moving the head back slightly will show an intake of air, while flaring the nostrils and having the head nod forward a little can show exhalation. Breathing movements should be very subtle and hardly noticeable...外文资料翻译—译文部分人体动画基础(引自 Peter Ratner.3D Human Modeling andAnimation[M].America:Wiley,2003:243~249)如果你读到了这部分，说明你很可能已构建好了人物角色，为它创建了纹理，建立起了人体骨骼，为面部表情制作了morph修改器并在模型周围安排好了灯光。

三维建模数字化设计英语

三维建模数字化设计英语In the realm of modern design, 3D modeling has revolutionized the way we conceptualize and create. It allows designers to visualize their ideas in a tangible form,bringing innovation to life with digital precision.The process of 3D modeling starts with a concept, whichis then translated into a digital blueprint. This blueprintis the foundation upon which the model is built, layer by layer, in a virtual space.As the model takes shape, each detail is carefullycrafted to ensure accuracy and functionality. The digitaltools at our disposal offer unparalleled control over the design, enabling us to make adjustments with ease.The versatility of 3D modeling extends beyond the design phase. It is instrumental in the prototyping process,allowing for the creation of physical models that can betested and refined before production.Moreover, 3D modeling has a significant impact on the manufacturing industry. It streamlines the production process, reducing costs and time, while ensuring the highest qualityof the final product.In the field of education, 3D modeling is an invaluable tool for teaching complex concepts. It provides students witha hands-on approach to learning, enhancing their understanding and creativity.Lastly, the integration of 3D modeling in various industries, from architecture to entertainment, showcases its potential to shape the future of design and innovation. It is a testament to the power of technology in transforming the way we create and interact with the world around us.。

英语论文翻译

Journal of The Institution of Engineers, SingaporeVol. 44 Issue 4 20043D RAPID REALIZATION OF INITIAL DESIGN FORPLASTIC INJECTION MOULDSMaria L.H. Low1 and K.S. Lee2ABSTRACTTo provide an initial design of the mould assembly for customers prior to receiving the final product CAD data is a preliminary work of any final plastic injection mould design. Traditionally and even up till now, this initial design is always created using 2D CAD packages. The information used for the initial design is based on the technical discussion checklist, in which most mould makers have their own standards. This technical discussion checklist is also being used as a quotation. This paper presents a methodology of rapid realization of the initial design in 3D solid based on the technical discussion checklist, which takes the role of the overall standard template. Information are extracted from databases and coupled with the basic information from customer, these information are input into the technical discussion checklist. Rules and heuristics are also being used in the initial mould design. A case study is provided to illustrate the use of the standard template and to exhibit its real application of rapid realization of the initial design for plastic injection moulds.INITIAL DESIGN OF PLASTIC INJECTION MOULDWhen the product CAD file is first received, the assigned project engineer or mould designer fills up a technical checklist during their first technical discussion with the customers. The checklist records information such as the resin material to be used and its shrinkage value, the number of cavities required by customers, the gating system, and the moulding machine to be used, the required type of mould base and other information needed to provide the basis of the initial design of the mould. Since this checklist contains most of the basic information, it doubles up as a quotation. This allows customers to decide whether to modify their product CAD file to produce a simpler mould that is cheaper. After that, the mould designer prepares an initial design based on the product CAD file and information in the checklist.Traditionally and even up till now, mould designers are using 2D CAD packages to create the initial design, although 3D CAD packages are readily available. Ironically, mould designers would then use the 3D CAD package only in their final mould design. When this initial design is completed, it will be presented on the next technical discussion.Modifications made to the initial design are normally done by marking and sketching thechanges on the printed drawing paper. Though there is no final product CAD file at this stage, the mould-maker could go ahead to purchase the raw materials and standard components subject to approval of the customers. After the final product CAD file has been received, the mould designer would start the actual mould design afresh using the3D CAD package that they have. This is a time consuming method since the initial design is not related to the final mould design.Provision had been made in this system to present representations of the core, cavity, slider head and lifter head as blocks in the initial design. These blocks can be edited to trim to the profile only when the final product CAD file has been received and confirmed. During the initial design, ejector pins/blades and cooling lines are still not includedbecause these depend greatly on the final product CAD file. Since this paper focuses on the rapid realization of initial design, core/cavity parting, profile creation, addition of ejector pins/blades and cooling lines will not be discussed here. 3D solids would be used as they have their advantages. The advantages of solid modeling are better visualization, simplified simulation, improved producability, faster drawing production and facilitates an integrated design process.Standardization methodStandardization method involves using standard mould designs, standard components anda standard working method of mould design. This means that every mould designer willdesign moulds in exactly the same method, use the same design assembly hierarchy tree,and use standard components from a specified supplier. This allows the different teamsinvolved in the mould project to speak the same language. The advantages are as follows:a) Easy following-up of mould project, b) Lower cost and faster delivery of components and c) Proper mould project management.Shrinkage factor & core/cavity creationA representation of the core and a representation of the cavity in the form of blocks are simultaneously created to encapsulate the scaled product CAD file. A default-offset value is applied to the range box of the scaled part to give the approximate size of the blocks (Figure1). These values are commonly used by mould designers locally and can be edited.Figure 1: Default-offset value between range box of the scaled part andcore/cavityOther accessories/secondary componentsThe secondary components that may need to be selected during the initial mould designer sliders, lifters and special inserts. Sliders and lifters will be the source of concern inthe layout assembly level as they played a part in determining the overall size of thelayout assembly. They are initially categorized into the general types and are available inthree basic sizes: Small (S), Medium (M) and Large (L). The respectivesub-designtemplates for the sliders and lifters are used to place the components to the appropriateundercuts. They also functions as an interface to allow users to edit the geometricalparameters or configurations of the secondary components. As this is the initial design,very accurate positioning is not required but the secondary components have to be at itscorrect location and orientation.Cavity layoutOnly standard types of cavity layout are used in this prototype system (Low et al. 2002).As the types of available layouts are fixed, the different types of layouts can be listed intoa configuration database that enables the required layout to be activated in the mould assembly during the mould design. This provides a faster method of designing. Thedesired new configuration can be reloaded via the sub-design template for cavity layout. In addition, the orientation, the distances between cavities, which are known as geometrical parameters can also be edited through the same interface.Selection of mould base sizeThe secondary components and cavity layout are assembled in the layout assembly. The over all size of the layout assembly needs to be known in order to select the appropriate mould base size. The system automatically loads the smallest possible mould base from the available configurations of the specified model of mould base that has been selected. Simultaneously, the system has to check the compatibility of the chosen mould base with the targeted injection mould machine that is to be used for mould the products. Parameters that are checked are the tie-bar dimensions, platen dimensions, mould height and maximum daylight of mould machine. A representation of the clamping unit of the chosen injection mould machine can be activated to allow the user to verify the design visually.Gating & runner designThe standard design of gates and runner are pre-created and store in a library database. Depending on the number of cavities that are indicated earlier, the appropriate configuration will be activated in the initial mould design. In this prototype system, some rules and heuristics are also set for the gating and runner design. The available options can be selected only after the type of mould base has been chosen since they are dependent on the type of mould base.The rules for selection of the gating are:1. For 2-plate mould, types of gating that can be used are all but pin-point gatingand hot-runner gating.2. For 3-plate mould, only pin-point gating and side gating can be used and notthe rest of the options.3. For hot runner moulds, only the different choices of hot runner gating can beused.The general rules in the design of runners are:1. For 2-plate moulds, runners with round cross-sections are being used.2. For 3-plate mould, runners with trapezoidal cross-sections are being used.3. For hot runner moulds, no runners are needed.A CASE STUDYThe test part that is used in this case study is a phone casing. The approximate size is 180mm ×60mm ×35mm. ABS that has a shrinkage value of 0.5% is used. The moulding machine used is a Toshiba 280-ton toggle type injection moulding machine. The dimensional information of the clamping unit is given in Table 1. Acloser observation of this test part reveals that there are three undercuts, thus requiring additional accessories such as lifters and sliders. Figure 6a illustrates the external undercuts that require sliders and Figure 6b shows an internal undercut that requires a lifter. A 2-plate mould with two cavities is also required for this test part. The information as supplied by the customer, are entered into or selected from the “Technical Discussion Checklist” interface that acts as a standard template for all mould projects. Then, the original product CAD file of the test part is scaled accordingly to the shrinkage factor provided by the interface. The core and cavity are also created at the same time to encapsulate the test part. The selected type of the mould base, gating system and the required accessories are copied into the respective levels of the mouldassembly structure.a bFigure 3: Application of sub-design template for lifter to test part Secondary components are attached to the core/cavity assembly. Figure 7 shows the application of the sub-design template for the lifter. A similar sub-design template is used separately for sliders. Since the requirement for this test part is to have a two-cavity layout, the linear two-cavity configuration is activated. Since there are sliders between the two cavities, an allowance is given between the cavities (Figure 3). This distance can be edited using the cavity layout sub-design interface. In this case study, the overall sizeof the layout is approximately 520mm ×250mm ×320mm (Figure 4). Thus, a mould base must have an ejector plate and ejector retainer plate that is larger than 520mm ×250mm. Since the mould base type that was chosen is the DME SF series, a smallest possible mould base is of the 4060 configuration. As the distance between the tie bars of the moulding machine is 730mm ×730mm, the selected mould base can be secured ontothe moulding machine without any difficulty. The completed initial design of the injection mould for the test part is shown in Figure 10. A representation of the clamping unit of the moulding machine can be activated to allow verification that the mould is designed correctly since it is easy to visualize them in 3D（Figure 5）.Figure 3: Providing allowance between cavitieFigure 4: Overall size of layout assembly of test partCONCLUSIONSAn approach to using the standardization method is applied to the rapid realization of the initial design of plastic injection moulds in this paper. Design processes that are the same for every mould design project are consolidated into a standard template. The technical discussion checklist takes on the role of the overall standard template while the sub designshave their own sub-templates. The use of databases allows the flexibility inallowing customization. Approximate costing of the mould can also be derived from the information based on the checklist. Other advantages include having a faster approach to design, designing a mould that functions and easy visualization.However, this rapid realization of initial design system has its limitations. As technology advances, more databases, rules and heuristics needs to be built into the system to accommodate for mould designs meant for the newer forms of plastic injection moulding such as multi-colour moulding and thin-wall moulding. Much effort and money needs to be invested by organizations to customize their systems to consider the new technologies. The databases for the materials and moulding machine also had to be constantly updated and checked to account for the newer materials and machines that are introduced into the industry. If there is a wrong entry in the databases, the results that are obtained can be disastrous. An experienced designer would know at once when the design is not right but to a novice designer, he/she may just accept the design without much thought, believing that the system would always provide the correct solution. The authors are currently researching into improving the system so as to enable an easier approach of customization.REFERENCESC HIN, K WAI-S ANG and T. N. W ONG, 1996, Knowledge-based evaluation for the conceptual design development of injection molding parts. Engineering Application of Artificial Intelligence, 9(4), 359-376L EE, K. S., Z. L I, J. Y. H, F UH, Y. F. Z HANG and A. Y. C. N EE, 1997, Knowledge-basedinjection mold design system. CIRP International Conference and Exhibition on Design and Production of Dies and Moulds, Turkey, June, 45-50L OW, M ARIA L. H. and K. S. L EE, 2002, A parametric-controlled cavity layout design system for plastic injection mould. The International Journal of Advanced Manufacturing Technology, Accepted for publicationLi Pang, Kamath G M, Wereley N M, Dynamic Characterization And Analysis Of Magnetorheological Damper Behavior, SPIE Conference on Passive Damping and Isolation SPIE Vol. 3327, pp 284-302, 1998M OK, C. K, K. S. C HIN and J OHN K. L. H O, 2001, An interactive knowledge-based CAD system for mould design in injection mould processe The International Journal of Advanced Manufacturing Technology, 17, 27-38Journal of The Institution of Engineers, SingaporeVol. 44 Issue 4 200430Y E, X. G., K. S. L EE, J. Y. H, F UH, Y. F. Z HANG and A. Y. C. N EE, 2000, Automatic initial design of injection mould. International Journal of Material & Product Technology, 15(6), 503-517工程师学会杂志，新加坡2004年4月44期第一卷通过三维模拟快速实现初步的模具设计Maria L.H. Low1 and K.S. Lee2摘要：对于任何最终的模具制造来说，提供给顾客一套有关此模具设计的初步CAD数据都是必要的，而且需要尽量的完善。

三维转换翻译理论英语作文

三维转换翻译理论英语作文1. In the realm of translation theory, there exists a fascinating concept known as three-dimensional translation. It's like a magical transformation that takes place when a text is transported from one language to another. It's like a journey through time and space, where words and ideas are reshaped and reimagined in a new linguistic landscape.2. Picture this: a translator sits at their desk, surrounded by dictionaries, reference books, and a cup of steaming coffee. They embark on a linguistic adventure, diving into the depths of a foreign language, decoding its intricacies and nuances. They become a linguistic chameleon, adapting to the linguistic environment and capturing the essence of the original text.3. Three-dimensional translation is not just about converting words from one language to another. It's about capturing the cultural context, the emotions, and thesubtle nuances that make a text come alive. It's aboutrecreating the magic of the original work in a new language, so that readers can experience the same joy, sadness, or excitement.4. Think of it as a puzzle, where each word and phrase fits together to create a bigger picture. The translator must carefully select the right pieces, arranging them in a way that faithfully represents the original text. It's like being a master chef, combining different ingredients to create a delicious dish that retains the essence of the original flavors.5. But three-dimensional translation is not without its challenges. It requires a deep understanding of both the source and target languages, as well as the cultural and social context in which the text was written. It's like walking a tightrope, balancing between staying true to the original and making the text accessible to a new audience.6. The beauty of three-dimensional translation lies in its ability to bridge the gap between different culturesand languages. It allows us to explore new worlds, to gaininsights into different ways of thinking and expressing ideas. It's like opening a door to a parallel universe, where words have the power to transport us to places we've never been before.7. So next time you read a translated work, take a moment to appreciate the artistry and skill that went into transforming it into a new language. Three-dimensional translation is a true labor of love, a dance between words and cultures that brings us closer together as global citizens.8. In conclusion, three-dimensional translation is a fascinating concept that goes beyond mere word-for-word conversion. It's an art form that requires creativity, cultural sensitivity, and a deep understanding of both the source and target languages. It's like a journey through time and space, where words and ideas are transformed and reshaped, creating a bridge between different cultures and languages.。

3d动画制作中英文对照外文翻译文献

3d动画制作中英文对照外文翻译文献预览说明:预览图片所展示的格式为文档的源格式展示,下载源文件没有水印,内容可编辑和复制中英文对照外文翻译文献(文档含英文原文和中文翻译)Spin: A 3D Interface for Cooperative WorkAbstract: in this paper, we present a three-dimensional user interface for synchronous co-operative work, Spin, which has been designed for multi-user synchronous real-time applications to be used in, for example, meetings and learning situations. Spin is based on a new metaphor of virtual workspace. We have designed an interface, for an office environment, which recreates the three-dimensional elements needed during a meeting and increases the user's scope of interaction. In order to accomplish these objectives, animation and three-dimensional interaction in real time are used to enhance the feeling of collaboration within the three-dimensional workspace. Spin is designed to maintain a maximum amount of information visible. The workspace is created using artificial geometry - as opposed to true three-dimensional geometry - and spatial distortion, a technique that allows all documents and information to be displayed simultaneously while centering the user's focus of attention. Users interact with each other via their respective clones, which are three-dimensional representations displayed in each user's interface, and are animated with user action on shared documents. An appropriate object manipulation system (direct manipulation, 3D devices and specific interaction metaphors) is used to point out and manipulate 3D documents.Keywords: Synchronous CSCW; CVE; Avatar; Clone; Three-dimensional interface; 3D interactionIntroductionTechnological progress has given us access to fields that previously only existed in our imaginations. Progress made in computers and in communication networks has benefited computer-supported cooperative work (CSCW), an area where many technical and human obstacles need to be overcome before it can be considered as a valid tool. We need to bear in mind the difficulties inherent in cooperative work and in the user's ability to perceive a third dimension.The Shortcomings of Two- Dimensional InterfacesCurrent WIMP (windows icon mouse pointer) office interfaces have considerable ergonomic limitations [1].(a) Two-dimensional space does not display large amounts of data adequately. When it comes to displaying massive amounts of data, 2D displays have shortcomings such as window overlap and the need for iconic representation of information [2]. Moreover, the simultaneous display of too many windows (the key symptom of Windowitis) can be stressful for users [3].(b) WIMP applications are indistinguishable from one another; leading to confusion. Window dis- play systems, be they XII or Windows, do not make the distinction between applications, con- sequently, information is displayed in identical windows regardless of the user's task.(c) 2D applications cannot provide realistic rep- resentation. Until recently, network technology only allowed for asynchronous sessions (electronic mail for example); and because the hardware being used was not powerful enough, interfaces could only use 2D representations of the workspace.Metaphors in this type of environment do not resemble the real space; consequently, it is difficult for the user to move around within a simulated 3D space.(d) 2D applications provide poor graphical user representations. As windows are indistinguish- able and there is no graphical relation between windows, it is difficult to create a visual link between users or between a user and an object when the user's behavior is been displayed [4].(e) 2D applications are not sufficiently immersive, because 2D graphical interaction is not intuitive (proprioception is not exploited) users have difficulties getting and remaining involved in the task at hand.Interfaces: New ScopeSpin is a new interface concept, based on real-time computer animation. Widespread use of 3D graphic cards for personal computers has made real-time animation possible on low-cost computers. The introduction of a new dimension (depth) changes the user's role within the interface, the use of animation is seamless and therefore lightens the user's cognitive load. With appropriate input devices, the user now has new ways of navigating in, interacting with and organizing his workspace. Since 1995, IBM has been working on RealPlaces [5], a 3D interface project. It was developed to study the convergence between business applications and virtual reality. The user environment in RealPlaces is divided into two separate spaces (Fig, 1): ? a 'world view', a 3D model which stores and organizes documents through easy object interaction;a 'work plane', a 2D view of objects with detailed interaction, (what is used in most 2D interfaces).RealPlaces allows for 3D organization of a large number ofobjects. The user can navigatethrough them, and work on a document, which can be viewed and edited in a 2D application that is displayed in the foreground of the 'world'. It solves the problem of 2D documents in a 3D world, although there is still some overlapping of objects. RealPtaces does solve some of the problems common to 2D interfaces but it is not seamless. While it introduces two different dimensions to show documents, the user still has difficulty establishing links between these two dimensions in cases where multi-user activity is being displayed. In our interface, we try to correct the shortcomings of 2D interfaces as IBM did in RealPlaces, and we go a step further, we put forward a solution for problems raised in multi-user cooperation, Spin integrates users into a virtual working place in a manner that imitates reality making cooperation through the use of 3D animation possible. Complex tasks and related data can be represented seamlessly, allowing for a more immersive experience. In this paper we discuss, in the first part, the various concepts inherent in simultaneous distant cooperative work (synchronous CSCW), representation and interaction within a 3D interface. In the second part, we describe our own interface model and how the concepts behind it were developed. We conclude with a description of the various current and impending developments directly related to the prototype and to its assessment.ConceptsWhen designing a 3D interface, several fields need to be taken into consideration. We have already mentioned real-time computer animation and computer-supported cooperative work, which are the backbone of our project. There are also certain fields of the human sciences that have directty contributed to thedevelopment of Spin. Ergon- omics [6], psychology [7] and sociology [8] have broadened our knowIedge of the way in which the user behaves within the interface, both as an individual and as a member of a group.Synchronous Cooperative WorkThe interface must support synchronous cooper- ative work. By this we mean that it must support applications where the users have to communicate in order to make decisions, exchange views or find solutions, as would be the case with tele- conferencing or learning situations. The sense of co-presence is crucial, the user needs to have an immediate feeling that he is with other people; experiments such as Hydra Units [9] and MAJIC [10] have allowed us to isolate some of the aspects that are essential to multimedia interactive meetings.Eye contact." a participant should be able to see that he is being looked at, and should be able to look at someone else. ? Gaze awareness: the user must be able to estab- fish a participant's visual focus of attention. ? Facial expressions: these provide information concerning the participants' reactions, their acquiescence, their annoyance and so on. ? GesCures. ptay an important role in pointing and in 3D interfaces which use a determined set of gestures as commands, and are also used as a means of expressing emotion.Group ActivitySpeech is far from being the sole means of expression during verbal interaction [1 1]. Gestures (voluntary or involuntary) and facial expressions contribute as much information as speech. More- over, collaborative work entails the need to identify other people's points of view as well as their actions [1 2,1 3]. This requires defining the metaphors which witl enable users involvedin collaborative work to understand what other users are doing and to interact withthem. Researchers I1 4] have defined various communication criteria for representing a user in a virtual environment. In DIVE (Distributed Interactive Virtual Environment, see Fig. 2), Benford and Fahl6n lay down rules for each characteristic and apply them to their own system [1 5]. lhey point out the advantages of using a clone (a realistic synthetic 3D representation of a human) to represent the user. With a clone, eye contact (it is possible to guide the eye movements of a clone) as well as gestures and facial expressions can be controlled; this is more difficult to accomplish with video images. tn addition to having a clone, every user must have a telepointer, which is used to designate obiects that can be seen on other users' displays.Task-Oriented InteractionUsers attending a meeting must be abte to work on one or several shared documents, it is therefore preferable to place them in a central position in the user's field of vision, this increases her feeling of participation in a collaborative task. This concept, which consists of positioning the documents so as to focus user attention, was developed in the Xerox Rooms project [1 6]; the underlying principle is to prevent windows from overlapping or becoming too numerous. This is done by classifying them according to specific tasks and placing them in virtual offices so that a singIe window is displayed at any one (given) time. The user needs to have an instance of the interface which is adapted to his role and the way he apprehends things, tn a cooperative work context, the user is physically represented in the interface and has a position relative to the other members of the group.The Conference Table Metaphor NavigationVisually displaying the separation of tasks seems logical - an open and continuous space is not suitable. The concept of 'room', in the visual and in the semantic sense, is frequently encountered in the literature. It is defined as a closed space that has been assigned a single task.A 3D representation of this 'room' is ideal because the user finds himself in a situation that he is familiar with, and the resulting interfaces are friendlier and more intuitive.Perception and Support of Shared AwarenessSome tasks entail focusing attention on a specific issue (when editing a text document) while others call for a more global view of the activity (during a discussion you need an overview of documents and actors). Over a given period, our attention shifts back and forth between these two types of activities [17]. CSCW requires each user to know what is being done, what is being changed, where and by whom. Consequently, the interface has to be able to support shared awareness. Ideally, the user would be able to see everything going on in the room at all times (an everything visible situation). Nonetheless, there are limits to the amount of information that can be simultaneously displayed on a screen. Improvements can be made by drawing on and adopting certain aspects of human perception. Namely, a field of vision with a central zone where images are extremely clear, and a peripheral vision zone, where objects are not well defined, but where movement and other types of change can be perceived.Interactive Computer AnimationInteractive computer animation allows for two things: first, the amount of information displayed can be increased, andsecond, only a small amount of this information can be made legible [18,19]. The remainder of the information continues to be displayed but is less legible (the user only has a rough view of the contents). The use of specific 3D algorithms and interactive animation to display each object enables the user visually to analyse the data quickly and correctly. The interface needs to be seamless. We want to avoid abstract breaks in the continuity of the scene, which would increase the user's cognitive load.We define navigation as changes in the user's point of view. With traditional virtual reality applica- tions, navigation also includes movement in the 3D world. Interaction, on the other hand, refers to how the user acts in the scene: the user manipulates objects without changing his overall point of view of the scene. Navigation and interaction are intrinsically linked; in order to interact with the interface the user has to be able to move within the interface. Unfortunately, the existence of a third dimension creates new problems with positioning and with user orientation; these need to be dealt with in order to avoid disorienting the user [20].Our ModelIn this section, we describe our interface model by expounding the aforementioned concepts, by defining spatial organization, and finally, by explaining how the user works and collaborates with others through the interface.Spatial OrganizationThe WorkspaceWhile certain aspects of our model are related to virtual reality, we have decided that since our model iS aimed at an office environment, the use of cumbersome helmets or gloves is not desirable. Our model's working environment is non-immersive.Frequently, immersive virtual reality environments tack precision and hinder perception: what humans need to perceive to believe in virtual worlds is out of reach of present simulation systems [26]. We try to eliminate many of the gestures linked to natural constraints, (turning pages in a book, for example) and which are not necessary during a meeting. Our workspace has been designed to resolve navigation problems by reducing the number of superfluous gestures which slow down the user. In a maI-life situation, for example, people sitting around a table could not easily read the same document at the same time. To create a simple and convenient workspace, situations are analysed and information which is not indispensable is discarded [27]. We often use interactive computer animation, but we do not abruptly suppress objects and create new icons; consequently, the user no longer has to strive to establish a mental link between two different representations of the same object. Because visual recognition decreases cognitive load, objects are seamlessly animated. We use animation to illustrate all changes in the working environment, i.e. the arrival of a new participant, the telepointer is always animated. There are two basic objects in our workspace: the actors and the artefacts. The actors are representations of the remote users or of artificial assistants. The artefacts are the applications and the interaction tools.The Conference tableThe metaphor used by the interface is the con- ference table. It corresponds to a single activity (our task-oriented interface solves the (b) shortcoming of the 2D interface, see Introduction). This activity is divided spatially and semantically into two parts. The first is asimulated panoramic view on which actors and sharedapplications are displayed. Second, within this view there is a workspace located near the center of the simulated panoramic screen, where the user can easily manipulate a specific document. The actors and the shared applications (2D and 3D) are placed side by side around the table (Fig. 4), and in the interest of comfort, there is one document or actor per 'wail'. As many applications as desired may be placed in a semi-circle so that all of the applications remain visible. The user can adjust the screen so that the focus of her attention is in the center; this type of motion resembles head- turning. The workspace is seamless and intuitive,Fig, 4. Objects placed around our virtual table.And simulates a real meeting where there are several people seated around a table. Participants joining the meeting and additional applications are on an equal footing with those already present. Our metaphor solves the (c) shortcoming of the 2D interface (see Introduction),DistortionIf the number of objects around the table increases, they become too thin to be useful. To resolve this problem we have defined a focus-of-attention zone located in the center of the screen. Documents on either side of this zone are distorted (Fig.5). Distortion is symmetrical in relation to the coordinate frame x=0. Each object is uniformly scaled with the following formula: x'=l-(1-x) '~, O<x<l< bdsfid="116" p=""></x<l<>Where is the deformation factor. When a= 1 the scene is not distorted. When all, points are drawn closer to the edge; this results in centrally positioned objects being stretched out, while those in the periphery are squeezed towards the edge. This distortion is similar to a fish-eye with only one dimension [28].By placing the main document in the centre of the screen and continuing to display all the other documents, our model simulates a human field of vision (with a central zone and a peripheral zone). By reducing the space taken up by less important objects, an 'everything perceivable' situation is obtained and, although objects on the periphery are neither legible nor clear, they are visible and all the information is available on the screen. The number of actors and documents that it is possible to place around the table depends, for the most part, on screen resolution. Our project is designed for small meetings with four people for example (three clones) and a few documents (three for example). Under these conditions, if participants are using 17-inch, 800 pixels screens all six objects are visible, and the system works.Everything VisibleWith this type of distortion, the important applications remain entirely legible, while all others are still part of the environment. When the simulated panoramic screen is reoriented, what disappears on one side immediately reappears on the other. This allows the user to have all applications visible in the interface. In CSCW it is crucial that each and every actor and artefact taking part in a task are displayed on the screen (it solves the (a) shortcoming of 2D interface, see Introduction),A Focus-of-Attention AreaWhen the workspace is distorted in this fashion, the user intuitively places the application on which she is working in the center, in the focus-of- attention area. Clone head movements correspond to changes of the participants' focus of attention area. So, each participant sees theother participants' clones and is able to perceive their headmovements. It gives users the impression of establishing eye contact and reinforces gaze awareness without the use of special devices. When a participant places a private document (one that is only visible on her own interface) in her focus in order to read it or modify it, her clone appears to be looking at the conference table.In front of the simulated panoramic screen is the workspace where the user can place (and enlarge) the applications (2D or 3D) she is working on, she can edit or manipulate them. Navigation is therefore limited to rotating the screen and zooming in on the applications in the focus-of-attention zone.ConclusionIn the future, research needs to be oriented towards clone animation, and the amount of information clones can convey about participant activity. The aim being to increase user collaboration and strengthen the feeling of shared presence. New tools that enable participants to adopt another participant's point of view or to work on another participant's document, need to be introduced. Tools should allow for direct interaction with documents and users. We will continue to develop visual metaphors that will provide more information about shared documents, who is manipulating what, and who has the right to use which documents, etc. In order to make Spin more flexible, it should integrate standards such as VRML 97, MPEG 4, and CORBA. And finally, Spin needs to be extended so that it can be used with bigger groups and more specifically in learning situations.旋转：3D界面的协同工作摘要：本文提出了一种三维用户界面的同步协同工作—旋转，它是为多用户同步实时应用程而设计，可用于例如会议和学习情况。

三视图专业英语作文

三视图专业英语作文The Essence of Orthographic Views in Engineering Design.Engineering design, an intricate process that involves the translation of ideas into tangible, functional products, relies heavily on accurate and precise representations. Among these representations, the orthographic views —commonly known as the three views or three-dimensional projection — play a pivotal role. These views, which encompass the front view, side view, and top view, providea comprehensive understanding of an object's dimensions, shape, and relative positions of its various parts.The front view, also known as the elevation, gives a clear picture of the object's face, revealing its lengthand height. It captures the details of the object's features, such as protrusions, indentations, and contours, which are critical for manufacturing purposes. This viewacts as a roadmap for the craftsmen, guiding them throughthe fabrication process.The side view, known as the profile, highlights the object's width and height. It provides an orthogonal perspective, offering a different perspective of theobject's form. This view is crucial in understanding how the object's sides interact with each other and how they contribute to the overall structure.The top view, or the plan, gives a bird's eye view of the object, showing its length and width. It offers a perspective that is perpendicular to the ground, allowing designers to visualize the object's layout and arrangement. This view is particularly useful in understanding how different components fit together and how they interact spatially.The integration of these three views creates a comprehensive, three-dimensional understanding of the object. Together, they eliminate any ambiguities or misunderstandings that could arise from relying solely on a single view. This integration is achieved through the use of projection lines, which connect corresponding points ondifferent views, ensuring that all dimensions are accurately represented.The importance of orthographic views extends beyond mere representation. They are the foundation of engineering drawings, which are essential for communication among designers, engineers, and manufacturers. These drawings act as a common language, bridging the gap between the abstract ideas of designers and the tangible realities of manufacturing.Moreover, the precision and accuracy of these views are crucial for ensuring the safety and reliability of engineered products. Any deviation from the specified dimensions or shapes could lead to structural failures or operational issues. Therefore, the meticulous attention to detail in creating these views is paramount.In conclusion, the orthographic views are the backbone of engineering design. They provide a comprehensive, three-dimensional understanding of an object, enabling designers, engineers, and manufacturers to communicate effectively andcreate safe, reliable products. As the field of engineering continues to evolve, the importance of these views remains unchanged, serving as the foundation for all engineering designs.。

关于TITAN3DGeo-view在水利水电信息工程中的应用论文外文翻译-中英文论文翻译

字数：共计2441字论文题目：关于TITAN 3D Geo-view在水利水电信息工程中的应用第一部分外文翻译About TITAN 3D Geo-view information in theWater Resources and Hydropower Engineering Abstract: TITAN 3D Geo-view is rapidly in recent years developed a geoscience data and computer combination of a new geo-information science and technology, which incorporates real-world objects in the geological position and related properties of organic combine to meet the user to learn information management,and with its unique geological data analysis and visualization of expression, a variety of decision support.Keywords: Water Resources and Hydropower; engineering one, TITAN 3D Geo-view three-dimensional visualization features Introduction to Science Information System (TITAN 3DGeo-view) is the first large-scale three-dimensional visualization of geo-information system software platform, is a'digital land 'Construction and land resource management and effective information technology tools for different users can extract some of these components characteristics, constitute a series of applications can also be basedon the user's specific needs, based on the core module to supplement the development, the formation of specialized applications. TITAN 3D Geo-view is built on grass-roots (data collection point), can be a variety of geological data collection, storage, management, processing and use of basic information systemsand integrated systems. The system has the following salient features: (1) with astrong theme of the core database, technical approach and stacked composite application model (2) using object-oriented technology, data warehouse technology and network technology, has a 'multi-S (DBS , CIS, RS, GPS, CADS and ES, etc.) 'combined with integrated features (3) the use of industry or sectorunified data model, a standard code system, standardized schema legend, the agreed approach and common software interface, a higher professional characteristics.Two, TITAN 3D Geo-view of research applications so far, domestic and foreign research to study three-dimensional visualization software has been a lot of information, but for its research applications, summarized the situation summedup in two ways First, the use of TITAN 3D Geo- view the system to handle the user's data; second is TITAN 3D Geo-view based on the development of the use ofits library to develop user-specific secondary three-dimensional visualization of geo-information system software has been successfully applied to include Water, water, underground utilities, disaster prevention and defense, underground caverns, mining and other items of engineering design and construction of the geological survey information for urban and rural construction, mineral exploitation and environmental protection of the project site, geological exploration, disaster prevention , project management and planning decision making and its product types include: (1) three-dimensional urban geology and groundwater resources management information system, (2) three-dimensional subsurface structure and engineering survey, design system, (3) three-dimensional design of mineral exploration and mining information systemsof these applications in real time, fast, dynamic access, management and processing of mineral resources, water conservancy, hydropower, roads, railways, tunnels, bridges, subways, air defense facilities, geological exploration,development and design and construction information, can be applied to urbanand rural construction, project management, environmental monitoring, seismic zoning, 'disaster prevention and planning decision-making.Three, TITAN 3D Geo-view in the construction of water conservancy and hydropower project applications will TITAN 3D Geo-view used in the construction of water conservancy and hydropower project, the digitization of information, visualization, visualized as a starting point, the construction processcan be complex image with an image to describe it, for the full, accurate and rapid analytical grasp of the whole construction process provides a powerful analyticaltool, to achieve the efficient application of engineering and scientific information management, and design visualization results, and thus to provide an intuitive decision-making and design image information to support this decision to the construction design and provides a simple science, image analysis and intuitive visualization tools designed to help promote water conservancy and hydropower,work smart, modern development, and greatly increase the project design and management the level of modernization, engineering design community to promote the 'design revolution.'1 TITAN 3D Geo-view three-dimensional modeling of three-dimensional data model, application of geological data is based on a series of geological survey data, including geological mapping in a variety of point-like data, including trenching,adits, shafts and drill holes and other linear data, as well as geological maps, geological data, such as flat profile and only after interpolation simulation, so thatone-dimensional, two-dimensional data after a three-dimensional characteristicsof three-dimensional, so we can not as a simple data one-dimensional, two-dimensional data structures to handle, and three-dimensional datastructures can not be directly described the need to seek a kind of hierarchy, bothline and surface description can describe the body, and one line into one side andthe surface after the topology methods to maintain, compared to the border instead of (B-Rep: Boundary Replace-ment) model is more appropriate. The model used to replace the physical boundaries of the entity, and by the boundary topology to create the link. space objects normally can be decomposed into a collection of four types of elements, namely point, line, surface and body, each element of the geometry data type, type, logo and the topological relationship between the composition of three-dimensional boundaries of the entity to represent it, and through space topology relationship to establish the boundariesof the contact is conducive to physical location and topology of space to maintain,but also conducive to further the three-dimensional geological model and the dynamic evolution of the shear vector simulation method using B-Rep model forhuman-computer interaction modeling process.2 TITAN 3D Geo-View-Aided Design Application SubsystemThe complexity of 3D editing, interactive three-dimensional geological data edit transition to TITAN 3D Geo-view two-dimensional editing subsystem, the approach include: (1) geological map, or directly edit the geological section, (2)the establishment of auxiliary section, directly edit the geological map or geological profile of the data mainly from the original trenching, adits, shafts and boreholes, etc. as raw data preparation, three-dimensional systems can also provide external interfaces to other format data imported into the system, suchas DXF, 3D, WAL, WAP, WAT, DEM, 3DV, BMP, SHP, CRD, CEX data formats,while providing external interfaces, other software applications to export systemfor the auxiliary section will provide users with cutting sections in the current model, the formation of the current model set position profile, enter the two-dimensional subsystem on the basis of geological knowledge and experience profile to edit amendment to the geological profile in line with current regional geology, edited After the edited profile information to a three-dimensional system, involved in modeling.Fourth, the prospect TITAN 3D Geo-view itself is in constant development, it isthe construction of water conservancy and hydropower projects in the application should also continue to develop. Application development, not onlywith TITAN 3D Geo-view itself is a combination of development, but also with the Water Resources and Hydropower Engineering combining professional in the construction of water conservancy and hydropower projects in the future, TITAN 3D Geo-view combined with other technologies will be more closely applied more widely.??? water conservancy and hydropower engineering layout visualization program requirements are not limited to simple The performance for interactive layout options to modify, component-based TI-TAN 3D Geo-view (ComTITAN 3D Geo-view) is an important application development trends. Conclusion TITAN 3D Geo-view powerful spatial analysis features and graphical display capabilities for engineering design and research results provide a strongvisual expression of modern methods, but, TITAN 3D Geo-view applied to the construction of water conservancy and hydropower projects there are many notwholly satisfactory, such as database modeling applications is still relatively weak,can be integrated with different technologies to overcome. With Ger, View the application of in-depth study, a single TITAN 3D Geo-view applications the existence of defects and deficiencies will be resolved and weaken gradually. integration of various techniques to become TITAN 3DGeo-view of the clear trends in the application, whether it is combined with simulation technology, orin the 3s, 4s, and more s the concept of integration, the embodied in a kind ofmultiple systems, multiple technology integration ideas, which will also promotethe TITAN 3DGeo-view of the more in-depth applications. With the large-scalewater conservancy and hydropower engineering information management, real-time, rapid demand Web-based transmission GIS application to become inthe future, TITAN3D Geo-view with the direction of applied research projects with short, should TITAN 3D Geo-view can be combined with other technology integration, give full play to their strengths, learn from each other in an integrated manner for the construction of water conservancy and hydropower project services第二部分中文论文关于TITAN 3D Geo-view在水利水电信息工程中的应用摘要：TITAN 3D Geo－view是近年来迅速发展起来的一门地学数据与计算机相结合的新型地学信息科学技术，它把现实世界中对象的地质位置和相关属性有机地结合起来，满足用户对地学信息的管理，并借助其特有的地学数据分析功能和可视化表达，进行各种辅助决策。

毕业设计外文文献翻译【范本模板】

毕业设计（论文)外文资料翻译系别：专业：班级:姓名：学号:外文出处:附件： 1. 原文; 2。

译文2013年03月附件一：A Rapidly Deployable Manipulator SystemChristiaan J。

J。

Paredis, H. Benjamin Brown，Pradeep K. KhoslaAbstract:A rapidly deployable manipulator system combines the flexibility of reconfigurable modular hardware with modular programming tools，allowing the user to rapidly create a manipulator which is custom-tailored for a given task. This article describes two main aspects of such a system，namely，the Reconfigurable Modular Manipulator System （RMMS)hardware and the corresponding control software。

1 IntroductionRobot manipulators can be easily reprogrammed to perform different tasks, yet the range of tasks that can be performed by a manipulator is limited by mechanicalstructure。

Forexample，a manipulator well-suited for precise movement across the top of a table would probably no be capable of lifting heavy objects in the vertical direction. Therefore，to perform a given task,one needs to choose a manipulator with an appropriate mechanical structure.We propose the concept of a rapidly deployable manipulator system to address the above mentioned shortcomings of fixed configuration manipulators。

3d模型介绍英语作文

3d模型介绍英语作文3D modeling is a fascinating and versatile form of art and technology that has revolutionized various industries, including animation, gaming, architecture, and manufacturing. It involves creating three-dimensional representations of objects using specialized software and techniques, allowing for a more realistic and immersive experience. In this essay, I will explore the significance of 3D modeling, its applications, and its impact on different fields.First and foremost, 3D modeling plays a crucial role in the entertainment industry, particularly in the creation of animated films, video games, and virtual reality experiences. By using 3D modeling software, artists and designers can bring their imaginative concepts to life, crafting visually stunning and lifelike characters, environments, and special effects. This has greatly enhanced the quality and realism of entertainment media, captivating audiences and pushing the boundaries ofcreativity.Moreover, 3D modeling has become an indispensable tool in the field of architecture and interior design.Architects and designers can use 3D modeling software to create detailed and accurate representations of buildings, interiors, and landscapes, allowing clients to visualize the final product before construction even begins. This not only streamlines the design process but also helps to identify and address potential issues, resulting in more efficient and cost-effective projects.Furthermore, 3D modeling has revolutionized the manufacturing industry, particularly in the realm of product design and prototyping. With the ability to create precise and intricate 3D models of products, manufacturers can test and refine their designs before production, reducing the risk of errors and minimizing waste. This has led to faster innovation, improved product quality, and ultimately, greater customer satisfaction.In addition to its practical applications, 3D modelingalso serves as a powerful tool for artistic expression and experimentation. Artists and creatives can use 3D modeling software to explore new forms, textures, and compositions, pushing the boundaries of traditional art and design. This has led to the emergence of innovative and thought-provoking works of art that challenge our perceptions and inspire new ways of thinking.Furthermore, 3D modeling has opened up newpossibilities for education and research, allowing students and scholars to explore and interact with complex concepts and phenomena in a virtual environment. For example, in the field of science, 3D models can be used to visualize and study molecular structures, astronomical phenomena, and biological systems, providing a deeper understanding of the natural world.In conclusion, 3D modeling has had a profound impact on various industries and aspects of our lives, from entertainment and design to manufacturing and education.Its ability to create realistic and immersive experiences, streamline processes, and foster creativity has made it aninvaluable tool for artists, designers, engineers, and educators alike. As technology continues to advance, the potential for 3D modeling to shape the future of our world is truly limitless.。

三维建模毕业论文英文文献翻译

毕业设计(论文)文献翻译Constructing Rules and Scheduling Technology for 3DBuilding ModelsZhengwei SUI, Lun WU, Jingnong WENG, Xing LIN, Xiaolu JIAbstract3D models have become important form of geographic data beyond conventional 2D geospatial data. Buildings are important marks for human to identify their environments, because they are close with human life, particularly in the urban areas. Geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. Architectural model data features with huge data volume, high complexity, non-uniform rules and so on. Hence, the cost of constructing large-scale scenes is high. Meanwhile, computers are lack of processing capacity upon a large number ofmodel data. Therefore, resolving the conflicts between limited processing capacity of computer and massive data of model is valuable. By investigating the characteristics of buildings and the regular changes of viewpoint in virtual 3D environment, this article introduces several constructing rules and scheduling techniques for 3D constructing of buildings, aiming at the reduction of data volume and complexity of model and thus improving computers’ efficiency at sc heduling large amount of architectural models. In order to evaluate the efficiency of proposed constructing rules and scheduling technology listed in the above text, the authors carry out a case study by 3D constructing the campus of Peking University using the proposed method and the traditional method. The two results are then examined and compared from aspects of model data volume, model factuality, speed of model loading, average responding time during visualization, compatibility and reusability in 3D geo-visualization platforms: China Star, one China’s own platform for 3D global GIS manufactured by the authors of this paper. The result of comparison reveals that models built by the proposed methods are much better than those built using traditional methods. For the constructing of building objects in large-scale scenes, the proposed methods can not only reduce the complexity and amount of model data remarkably, but can also improving computers’ efficiency.Keywords:Constructing rules, Model scheduling, 3D buildingsI. INTRODUCTIONIn recent years, with the development of 3D GIS (Geographical Information System) software like Google Earth, Skyline, NASA World Wind, large-scale 3D building models with regional characteristics have become important form of geographic data beyond conventional 2D geospatial data, like multi-resolution remote sensing images and vector data [1].Compared to traditional 2D representation, geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. 3D representation and visualization provides better visual effect and vivid urban geographic information, and thus plays an important role in people's perceptions of their environment. Meanwhile, the 3D building data is also of great significance for the construction of digital cities.But how to efficiently visualize thousands of 3D building models in a virtual 3D environment is not a trivial question. The most difficult part of the question is the conflicts between limited processing capacity of computer and massive volume of model data, particularly in the procedure of model rendering. Taking the 3D modeling of a city for the example using traditional 3D modeling method, suppose there are 100 000 buildings to model in the urban area and the average size of model data for eachbuilding is roughly 10 M. So the total data volume of building models in the city could reach a TB level. However, the capacity of ordinary computer memory is only in the GB scale. Based on this concern, the authors proposed the scheduling technology for large-scale 3D buildings models in aspects of model loading and rendering. Due to the lack of building constructing rules and standard, models of buildings vary in aspects of constructing methods, textures collection and model data volume, especially in aspects of model reusability and factuality. Such a large amount of data without uniform constructing rules becomes a huge challenge for data storage, processing and visualization in computers. It also brings the problem of incompatibility among different 3D GIS systems.After years of research in GIS (Geographic Information System), people have accumulated a number of ways to solve the above problems [3]. However in virtual 3D environment, because of the difference in data organization and manners of human computer interaction (HCI), we need to apply a new standardized method of modeling and scheduling for 3D models. At present, there is no such a uniform method as the constructing specification or standard for the modeling of 3D buildings. Existing approaches are insufficient and inefficient in the scheduling of large-scale building models, resulting in poor performance or large memory occupancy. In response to such questions, the authors proposed a new method for the construction of 3D building models. Models built using the proposed methods could be much better than those built using traditional methods. For the 3D modeling of building objects in scenes of large scale, the proposed methods can not only remarkably reduce the complexity and amount of model data, but can also improving the reusability and factuality of models. Concerning the scheduling of large-scale building models, the Model Loading Judgment Algorithm (MLJA) proposed in this paper could solve the optimal judgment problem of model loading in 3D vision cone, particularly in circumstance with uncertain user interactions.This paper first examines and analyzes existing problems in constructing and scheduling steps of 3D building models. Then the authors propose a set of constructing rules for 3D building models together with methods of modeloptimization. Besides, special scheduling technology and optimization method for model rendering is also applied in this paper for large-scale 3D building models. In order to evaluate the efficiency of proposed rules and methods, a case study is undertaken by constructing a 3D model for the main campus of Peking University and Shenzhen using both the proposed method and the traditional method respectively. The two resulting 3D models of Peking University campus and Shenzhen are then examined and compared with one other in aspects of model data volume, model factuality, speed of model loading, average responding time during visualization, compatibility and reusability in various 3D geo-visualization platforms like China Star (one China’s own platform for 3D global GIS manufactured by the authors), Skyline, etc. Result of comparison tells that provided similar factuality of models, using the proposed method of us, the data volume of models was reduced by 86%; the speed of model loading was increased by 70%; the average responding time of model during visualization and interaction speed was reduced by 83%. Meanwhile, the compatibility and reusability of 3D model data are also improved if they are constructed using our approach.II. MODELING RULES OF 3D BUILDINGS 3D scene is the best form of visualization for digital city systems. While constructing 3D models for buildings objects, proper methods and rules should be used, which are made with full concerns of the characteristics of 3D building models [2]. The resulting models should be robust, reusable and suitable enough for transmission over computer network, and should at the same time be automatically adapted to system capability.Generally speaking, methods of constructing 3D building models can be classified into three types: wireframe modeling, surface modeling and solid modeling. In normal circumstances, to model buildings in 3D format, the framework of building should be constructed first according to the contour features, number of floors, floor height, aerial photograph and liveaction photos of buildings. Then, gather the characteristics of scene that the buildings to model are representing. Importantcharacteristics include buildings aerial photograph or liveaction shooting photos. Finally, map the gathered texture to model framework, optimize the model and create database of the 3D building models.Although there have already been many approaches for the construction of 3D building models, a unified modeling method and rules are still needed to improve the efficiency, quality, facilitate checking, reusability and archiving of constructed models. By investigating the characteristics of buildings, we found that buildings have regular geometric solid for modeling, similar texture on the surfaces of different directions, high similarity in small-scale models of buildings, etc. According to these, this article gives a discussion on the modeling rules from three aspects, including constructing rules of the 3D building models, texture mapping rules of 3D building models and optimization method for constructed models based on mentioned constructing rules.A. Constructing rules of the 3D building modelsThe 3D building modeling refers to the procedure of representing true buildings from the real world into computer in the form of 3D objects [4]. Human beings, as the creator and at the same time potential users of models, play a key role in this procedure. People are different from each other in the understanding of the building objects, methods of modeling and the software tools they use for modeling. Such differences among people who carry out modeling work at the same time lead to the 3D models of diverse quality and low efficiency. So the 3D building constructing rules proposed in this article become necessary and helpful to solve the above problems.1) Combine similar floors as a whole and keep the roof independent2) Share similar models and process the details especially3) Constructing in the unit of meters4) Define central point of the model5) Unified model codes6) Reduce number of surfaces in a single model7) Reduce combination of the models8) Rational split of modelsB. Texture mapping rules of 3D buildingsBased on the framework of 3D models, we need to attach these models with proper textures to create a better visualization effect for 3D buildings. The quality of texture mapping has a direct impact on the visual effect of the scene whiling being rendered [5]. Since the graphics card of computer will load all the textures together when rendering a model, texture mapping rules and the quality of the texture mapping can directly influence the efficiency of rendering as well.C. Optimization of models based on constructing rulesBased on constructing rules and the characteristics of 3D building models, the authors develop a software tool to optimize the 3D building models automatically. The optimizations implemented in the software tool contain the deletion of models’ internal textures, merging adjacent vertices/lines/surfaces, removing un-mapped framework and so on. Besides, the software can enhance the shape of the whole model, texture position and model facticity in the procedure of model optimization.III. SCHEDULING TECHNOLOGY OF LARGE-SCALE 3DBUILDING MODELSFor the 3D visualization of large-scale architectural models, a series of measures could be applied to ensure the efficient rendering of models. Important measures includes the scene organization, vision cone cutting, elimination of textures on the backside of models, Shader optimization, LOD Algorithm, math library optimization, memory allocation optimization, etc..How to display thousands of 3D city buildings’ models in a virtual 3D environment is not trivial. The main problem is the scheduling of models [7]. It determines when and which models to be loaded. This problem can be divided into two smaller problems: Find visible spatial region of models in 3D environment, and optimization method of model rendering efficiency.A. Find visible spatial region of models in 3D environmentAccording to operating mechanism of computers during 3D visualization and thecharacteristics of large-scale 3D scene, we need to determine the position of current viewpoint first before loading signal models or urban-unit models. Then in response to the regular changes of viewpoint in virtual 3D environment, the system will preload the 3D model data into memory automatically. In this way, frequent IO operations can be reduced and thus overall efficiency of system gets improved. A new algorithm named MLJA (Model Loading Judgment Algorithm) is proposed in this paper in order to find out visible region of models in the 3D environment. The algorithm integrates the graticules and elevation information to determine the current viewpoint of users in the 3D space. And with the movement of viewpoint, the algorithm schedules the loading of model correspondingly and efficiently.B. Optimization method of model rendering efficiencyThe scheduling method of large-scale 3D building models proposed above is an effective way to solve the problem caused the contradiction between large model data volume and limited capacity of computers. According to the algorithm, we can avoid loading the whole large-scale 3D building models at one time for the sake of limited computer memory, and then improve system efficiency in the procedure of model loading and abandoning. Due to the limited capacity of GPU and local video memory, we need a further research on how to display the loaded model data in more efficient manner. In the remaining part of this paper, the authors will continue to introduce several methods on the optimization of model rendering in the vision cone.1) Elimination of textures on the backside of modelsThe backside of the 3D model is invisible to the users. If we omit the texture mapping for the 3D model on the backside, the processing load of graphic card will be reduced as much as at least 50%. Besides, according to an investigation on procedure of actual model rendering, the authors found that on the backside of the 3D model, the invisible texture is rendered in a counter-clockwise manner against the direction of eyesight, while the visible texture mapping is rendered in clockwise manner. So we can omit the rendering of models which is intended to be rendered in counterclockwise manner. Therefore, the textures won’t exist on the back of 3D models. The graphic card could then work more rapidly and efficiently.2) Eliminate the shielded modelBy calculating the geometric relationship between 3D models in the scene, the shielded models can be omitted while displaying the scene with appropriate shielding patches. Through this way, we can effectively reduce the usage of graphics card memory, and thus achieve higher rendering efficiency and faster 3D virtual system.In the virtual 3D geographic information system, we often observe 3D models from a high altitude. It is especially true for large-scale outdoor 3D models. The usual arrangement of 3D building models are always sparse, however the real block is very small. Therefore, establishing an index for visual control, which is similar to the BSP tree, doesn’t amount to much. Through carefully studying DirectX, we found that we can take advantage of the latest Z-buffering technology of DirectX to implement the shielding control of models.3) Optimization method of the Shader instructionsIn shader 3.0 technology, SM (Shader Model) is a model which can optimize the rendering engine. A 3D scene usually contains several shaders. Among these shaders, some deal with the surfaces and skeletons of buildings, and others deal with the texture of 3D building models.Geometry can be handled quickly by shader batch process. The shader can combine similar culmination in 3D building models, deal with the correlation operation of a single vertex, determine the physical shape of the model, link the point, line, triangle and other polygons for a rapid processing while create new polygons, etc. We can assign the computing task to shader and local video memory directly in a very short time without bothering the CPU. In this case, visual effects of smoke, explosions and other special effects and complex graphics are no longer necessary to be processed by the CPU of computer. Such features of shader can speed up both the CPU and graphic card in processing huge amount of 3D models.4) LOD algorithm of large-scale 3D sceneLOD (Level of Detail) is a common and effective solution to resolve the conflicts between real time visualization and the authenticity of models [8]. By investigating the main features and typical algorithms of LOD technology, the authorsproposed a new structure for dynamic multi-level display. This structure not only can be applied to the mesh simplification of models with many different but fixed topologies, but also can be applied to the mesh simplification of models with variable topology. Therefore, the LOD technology can be applied to any grid model. Based on the above concerns, the authors also design a mesh simplification algorithm for variable topology through vertices merge. Via the dual operations of vertex merging and splitting, we can achieve smooth transition across different LOD levels of models, and automatically change the model topology.These above techniques plays important role in 3D scene. It can not only enable a rapid visualization of large-scale scene, but also can provide a high-resolution display of scene at a local scale with plenty of architectural details.IV. CONCLUDING REMARKSConstructing rules and scheduling technology plays an important role in the application of large-scale 3D buildings. Since people’s demand for 3D expression brings a challenge of high-efficiency and high-quality to virtual 3D environment, the methods proposed in this article give a good try in these aspects. According to the authors’ research and case studies in this paper, integration of constructing rules and scheduling technology is promising in providing powerful tools to solve the conflicts between limited processing capacity of computer and massive data of models. The result of our case study on Peking University indicates that the proposed new method on constructing rules and scheduling technology for large-scale 3D scene is highly feasible and efficient in practice. The proposed methods can not only standardize the procedure of model construction, but also can significantly shorten the time taken in scheduling large-scale 3D buildings. It introduces a new effective way to develop applications for large-scale three-dimensional scene.构建三维建筑模型的规则和调度技术隋正伟，邬伦, 翁敬农，林星,季晓璐摘要三维模型已成为超越了传统的二维地理空间数据的一种重要的地理数据形式。

毕业论文翻译英文原文和译文

毕业论文翻译英文原文和译文Failure Properties of Fractured Rock Masses as AnisotropicHomogenized MediaIntroductionIt is commonly acknowledged that rock masses always display discontinuous surfaces of various sizes and orientations usually referred to as fractures or joints Since the latter have much poorer mechanical characteristics than the rock material they play a decisive role in the overall behavior of rock structureswhose deformation as well as failure patterns are mainly governed by those of the joints It follows that from a geomechanical engineering standpoint design methods of structures involving jointed rock masses must absolutely account for such weakness surfaces in their analysisThe most straightforward way of dealing with this situation is to treat the jointed rock mass as an assemblage of pieces of intact rock material in mutual interaction through the separating joint interfaces Many design-oriented methods relating to this kind of approach have been developed in the past decades among themthe well-known block theory which attempts to identify poten-tially unstable lumps of rock from geometrical and kinematical considerations Goodman and Shi 1985 Warburton 1987 Goodman 1995 One should also quote the widely used distinct element method originating from the works of Cundall and coauthors Cundall and Strack 1979 Cundall 1988 which makes use of an explicit nite-difference numerical scheme for computing the displacements of the blocks considered as rigid or deformable bodies In this context attention is primarily focused on the formulation of realistic models for describing the joint behavior Since the previously mentioned direct approach is becoming highly complex and then numerically untractable as soon as a very large number of blocks is involved it seems advisable to look for alternative methods such as those derived from the concept of homogenization Actually such a concept is already partially conveyed in an empirical fashion by the famous Hoek and Browns criterion Hoek and Brown 1980 Hoek 1983 It stems from the intuitive idea that from a macroscopic point of view a rock mass intersected by a regular network of joint surfaces may be perceived as a homogeneous continuum Furthermore owing to the existence of joint preferential orientations one should expect such a homogenized material to exhibit anisotropic propertiesThe objective of the present paper is to derive a rigorous formulation for the failure criterion of a jointed rock mass as a homogenized medium from the knowledge of the joints and rock material respective criteriaIn the particular situation where twomutually orthogonal joint sets are considered a closed-form expression is obtained giving clear evidence of the related strength anisotropy A comparison is performed on an illustrative example between the results produced by the homogenization methodmaking use of the previously determined criterion and those obtained by means of a computer code based on the distinct element method It is shown that while both methods lead to almost identical results for a densely fractured rock mass a size or scale effect is observed in the case of a limited number of joints The second part of the paper is then devoted to proposing a method which attempts to capture such a scale effect while still taking advantage of a homogenization technique This is achieved by resorting to a micropolar or Cosserat continuum description of the fractured rock mass through the derivation of a generalized macroscopic failure condition expressed in terms of stresses and couple stresses The implementation of this model is nally illustrated on a simple example showing how it may actually account for such a scale effect Problem Statement and Principle of Homogenization ApproachThe problem under consideration is that of a foundation bridge pier or abutment resting upon a fractured bedrock Fig 1 whose bearing capacity needs to be evaluated from the knowledge of the strength capacities of the rock matrix and the joint interfaces The failure condition of the former will be expressed through the classicalMohr-Coulomb condition expressed by means of the cohesion and the friction angle Note that tensile stresses will be counted positive throughout the paperLikewise the joints will be modeled as plane interfaces represented by lines in the gures plane Their strength properties are described by means of a condition involving the stress vector of components στacting at any point of those interfacesAccording to the yield design or limit analysis reasoning the above structure will remain safe under a given vertical load Q force per unit length along the Oz axis if one can exhibit throughout the rock mass a stress distribution which satises the equilibrium equations along with the stress boundary conditionswhile complying with the strength requirement expressed at any point of the structureThis problem amounts to evaluating the ultimate load Q＋ beyond which failure will occur or equivalently within which its stability is ensured Due to the strong heterogeneity of the jointed rock mass insurmountable difculties are likely to arise when trying to implement the above reasoning directly As regards for instance the case where the strength properties of the joints are considerably lower than those of the rock matrix the implementation of a kinematic approach would require the use of failure mechanisms involving velocity jumps across the joints since the latter would constitute preferential zones for the occurrence offailure Indeed such a direct approach which is applied in most classical design methods is becoming rapidly complex as the density of joints increases that is as the typical joint spacing l is becoming small in comparison with a characteristic length of the structure such as the foundation width BIn such a situation the use of an alternative approach based on the idea of homogenization and related concept of macroscopic equivalent continuum for the jointed rock mass may be appropriate for dealing with such a problem More details about this theory applied in the context of reinforced soil and rock mechanics will be found in de Buhan et al 1989 de Buhan and Salenc on 1990 Bernaud et al 1995Macroscopic Failure Condition for Jointed Rock MassThe formulation of the macroscopic failure condition of a jointed rock mass may be obtained from the solution of an auxiliary yield design boundary-value problem attached to a unit representative cell of jointed rock Bekaert and Maghous 1996 Maghous et al1998 It will now be explicitly formulated in the particular situation of two mutually orthogonal sets of joints under plane strain conditions Referring to an orthonormal frame Owhose axes are placed along the joints directions and introducing the following change of stress variablessuch a macroscopic failure condition simply becomeswhere it will be assumed thatA convenient representation of the macroscopic criterion is to draw the strength envelope relating to an oriented facet of the homogenized material whose unit normal n I is inclined by an angle a with respect to the joint direction Denoting by and the normal and shear components of the stress vector acting upon such a facet it is possible to determine for any value of a the set of admissible stresses deduced from conditions 3 expressed in terms of The corresponding domain has been drawn in Fig 2 in the particular case whereTwo comments are worth being made1 The decrease in strength of a rock material due to the presence of joints is clearly illustrated by Fig2 The usual strength envelope corresponding to the rock matrix failure condition is truncated by two orthogonal semilines as soon as condition is fullled2 The macroscopic anisotropy is also quite apparent since for instance the strength envelope drawn in Fig 2 is dependent on the facet orientation a The usual notion of intrinsic curve should therefore be discarded but also the concepts of anisotropic cohesion and friction angle as tentatively introduced by Jaeger 1960 or Mc Lamore and Gray 1967 Nor can such an anisotropy be properly described by means of criteria based on an extension of the classical Mohr-Coulomb condition using the concept of anisotropy tensor Boehler and Sawczuk 1977 Nova 1980 Allirot and Bochler1981Application to Stability of Jointed Rock ExcavationThe closed-form expression 3 obtained for the macroscopic failure condition makes it then possible to perform the failure design of any structure built in such a material such as the excavation shown in Fig 3where h and βdenote the excavation height and the slope angle respectively Since no surcharge is applied to the structure the specic weight γof the constituent material will obviously constitute the sole loading parameter of the systemAssessing the stability of this structure will amount to evaluating the imum possible height h beyond which failure will occur A standard dimensional analysis of this problem shows that this critical height may be put in the formwhere θjoint orientation and K nondimensional factor governing the stability of the excavation Upper-bound estimates of this factor will now be determined by means of the yield design kinematic approach using two kinds of failure mechanisms shown in Fig 4Rotational Failure Mechanism [Fig 4 a ]The rst class of failure mechanisms considered in the analysis is a direct transposition of those usually employed for homogeneous and isotropic soil or rock slopes In such a mechanism a volume of homogenized jointed rock mass is rotating about a point Ω with an angular velocity ωThe curve separating this volume from the rest of the structure whichis kept motionless is a velocity jump line Since it is an arc of the log spiral of angle and focus Ω the velocity discontinuity at any point of this line is inclined at angle wm with respect to the tangent at the same pointThe work done by the external forces and the imum resisting work developed in such a mechanism may be written as see Chen and Liu 1990 Maghous et al 1998where and dimensionless functions and μ1 and μ2 angles specifying the position of the center of rotation ΩSince the kinematic approach of yield design states that a necessary condition for the structure to be stable writesit follows from Eqs 5 and 6 that the best upper-bound estimate derived from this rst class of mechanism is obtained by minimization with respect to μ1 and μ2which may be determined numericallyPiecewise Rigid-Block Failure Mechanism [Fig 4 b ]The second class of failure mechanisms involves two translating blocks of homogenized material It is dened by ve angular parameters In order to avoid any misinterpretation it should be specied that the terminology of block does not refer here to the lumps of rock matrix in the initial structure but merely means that in the framework of the yield design kinematic approach a wedge of homogenized jointed rock mass isgiven a virtual rigid-body motionThe implementation of the upper-bound kinematic approachmaking use of of this second class of failure mechanism leads to the following results where U represents the norm of the velocity of the lower block Hence the following upper-bound estimate for KResults and Comparison with Direct CalculationThe optimal bound has been computed numerically for the following set of parametersThe result obtained from the homogenization approach can then be compared with that derived from a direct calculation using the UDEC computer software Hart et al 1988 Since the latter can handle situations where the position of each individual joint is specied a series of calculations has been performed varying the number n of regularly spaced joints inclined at the same angleθ 10° with the horizontal and intersecting the facing of the excavation as sketched in Fig 5 The corresponding estimates of the stability factor have been plotted against n in the same gure It can be observed that these numerical estimates decrease with the number of intersecting joints down to the estimate produced by the homogenization approach The observed discrepancy between homogenization and direct approaches could be regarded as a size or scale effect which is not included in the classicalhomogenization model A possible way to overcome such a limitation ofthe latter while still taking advantage of the homogenization concept as a computational time-saving alternative for design purposes could be to resort to a description of the fractured rock medium as a Cosserat or micropolar continuum as advocated for instance by Biot 1967 Besdo 1985 Adhikary and Dyskin 1997 and Sulem and Mulhaus 1997 for stratied or block structures The second part of this paper is devoted to applying such a model to describing the failure properties of jointed rock media均质各向异性裂隙岩体的破坏特性概述由于岩体表面的裂隙或节理大小与倾向不同人们通常把岩体看做是非连续的尽管裂隙或节理表现出的力学性质要远远低于岩体本身但是它们在岩体结构性质方面起着重要的作用岩体本身的变形和破坏模式也主要是由这些节理所决定的从地质力学工程角度而言在涉及到节理岩体结构的设计方法中软弱表面是一个很重要的考虑因素解决这种问题最简单的方法就是把岩体看作是许多完整岩块的集合这些岩块之间有很多相交的节理面这种方法在过去的几十年中被设计者们广泛采用其中比较著名的是块体理论该理论试图从几何学和运动学的角度用来判别潜在的不稳定岩块Goodman 石根华 1985Warburton 1987Goodman 1995另外一种广泛使用的方法是特殊单元法它是由Cundall及其合作者Cundall Strack 1979 Cundall 1988提出来的其目的是用来求解显式有限差分数值问题计算刚性块体或柔性块体的位移本文的重点是阐述如何利用公式来描述实际的节理模型既然直接求解的方法很复杂数值分析方法也很难驾驭同时由于涉及到了数目如此之多的块体所以寻求利用均质化的方法是一个明智的选择事实上这个概念早在Hoek-Brown准则Hoek Brown 1980Hoek 1983得出的一个经验公式中就有所涉及它来自于宏观上的一个直觉被一个规则的表面节理网络所分割的岩体可以看做是一个均质的连续体由于节理倾向的不同这样的一个均质材料显示出了各向异性的性质本文的目的就是从节理和岩体各自准则出发推求出一个严格准确的公式来描述作为均匀介质的节理岩体的破坏准则先考查特殊情况从两组相互正交的节理着手得到一个封闭的表达式清楚的证明了强度的各向异性我们进行了一项试验把利用均质化方法得到的结果和以前普遍使用的准则得到的结果以及基于计算机编程的特殊单元法DEM得到的结果进行了对比结果表明对于密集裂隙的岩体结果基本一致对于节理数目较少的岩体存在一个尺寸效应或者称为比例效应本文的第二部分就是在保证均质化方法优点的前提下致力于提出一个新的方法来解决这种尺寸效应基于应力和应力耦合的宏观破坏条件提出利用微极模型或者Cosserat连续模型来描述节理岩体最后将会用一个简单的例子来演示如何应用这个模型来解决比例效应的问题问题的陈述和均质化方法的原理考虑这样一个问题一个基础桥墩或者其邻接处建立在一个有裂隙的岩床上Fig1岩床的承载能力通过岩基和节理交界面的强度估算出来岩基的破坏条件使用传统的莫尔-库伦条件可以用粘聚力C 1和内摩擦角 m 来表示本文中张应力采用正值计算同样用接触平面代替节理图示平面中用直线表示强度特性采用接触面上任意点的应力向量στ表示根据屈服设计或极限分析推断如果沿着应力边界条件岩体应力分布满足平衡方程和结构任意点的强度要求那么在一个给定的竖向荷载Q沿着OZ 轴方向作用下上部结构仍然安全这个问题可以归结为求解破坏发生处的极限承载力Q 或者是多大外力作用下结构能确保稳定由于节理岩体强度的各向异性若试图使用上述直接推求的方法难度就会增大很多比如由于节理强度特性远远低于岩基从运动学角度出发的方法要求考虑到破坏机理这就牵涉到了节理上的速度突跃而节理处将会是首先发生破坏的区域这种应用在大多数传统设计中的直接方法随着节理密度的增加越来越复杂确切地说这是因为相比较结构的长度如基础宽B而言典型节理间距L变得更小加大了问题的难度在这种情况下对节理岩体使用均质化方法和宏观等效连续的相关概念来处理可能就会比较妥当关于这个理论的更多细节在有关于加固岩土力学的文章中可以查到de Buhan等 1989de Buhan Salenc 1990Bernaud等 1995 节理岩体的宏观破坏条件节理岩体的宏观破坏条件公式可以从对节理岩体典型晶胞单元的辅助屈服设计边值问题中得到Bekaert Maghous 1996 Maghous等 1998现在可以精确地表示平面应变条件下两组相互正交节理的特殊情况建立沿节理方向的正交坐标系O 并引入下列应力变量宏观破坏条件可简化为其中假定宏观准则的一种简便表示方法是画出均质材料倾向面上的强度包络线其单位法线n的倾角α为节理的方向分别用σn 和τn 表示这个面上的正应力和切应力用表示条件3推求出一组许可应力σnτn 然后求解出倾角α当α≥ m 时相应的区域表示如图2所示并对此做出两个注解如下1 从图2中可以清楚的看出节理的存在导致了岩体强度的降低通常当时强度包络线和岩基破坏条件相一致其前半部分被两个正交的半条线切去2 宏观各向异性很显著比如图2中的强度包络线决定于方位角α应该抛弃固有曲线和各向异性粘聚力与摩擦角的概念其中后一个概念是由Jaeger1960或Mc Lamore Gray1967所引入的通过莫尔-库伦条件进行扩展利用各向异性张量的方法来描述各向异性也是不妥当的Boehler Sawczuk 1977 Nova 1980Allirot Bochler 1981在节理岩体开挖稳定性中的应用式3的封闭形式是从宏观破坏条件中得到的该式可以用来对此种材料的结构体进行破坏设计如图3所示的开挖h 和β分别表示开挖高度和边坡角由于结构上没有其他荷载材料比重γ就成为系统唯一的加载参数该结构的稳定性评价需要在破坏发生的部位算出最大可能高度 h通过标准量纲分析表明这个临界高度表示为其中θ为节理方位角K 为表示开挖部位稳定性的一个无量纲因子该因子的上界估计值可以分别使用图4所示的两种类型的破坏机制通过屈服设计的运动学方法来确定转动破坏机理 [Fig 4 a ]第一种类型的破坏机制通常把分析对象直接转换为均匀各向同性的岩坡或土坡若采用这种破坏机制各向同性的节理岩体围绕点Ω产生角速度为ω的旋转把静止的部分和运动的部分分开的曲线即为速度突跃线在这条角度为 m 圆心为Ω的滑弧上的任意一点上速度都不是连续的速度方向与该点处的切线成倾角 m在这种破坏机制下外力所做的功和最大抵抗功可以表示为下列形式Chen Liu 1990Maghous 等w e 和w mr为无量纲函数μ1 和μ2 为滑移体的圆心角由于屈服设计状态的动力学方法是结构稳固的一个必要条件故有联立5式和6式取μ1 和μ2 的最小值进行计算可以得到第一种类型破坏机制的最佳上界估计分段刚性块体破坏机理[Fig 4 b ]第二种类型的破坏机制涉及到了两种均匀材料块体的转换由五个角度参数定义为了避免误解应该具体指出块体并不是指代初始状态下的岩基块体在屈服设计运动学方法的框架下它代表的不仅仅这个意思一块均质节理岩体的运动可以近似看做是刚体运动对于第二种类型的破坏机制运用上界运动学方法可以得出以下结果在Fréard 2000 的文中可以找到详细的计算过程其中U 表示下盘块体的速度如图4-b所示因此K上界估计值为计算结果以及与直接计算结果之间的对比经过计算选定最优上界参数值为屈服时有利用UDEC软件Hart等 1988对均质化方法的计算结果和直接计算方法的结果进行对比发现当每一个节理的位置都已知时利用后一种方法就可以求解这个问题当节理间隙很规则且倾角保持在与水平成10 °的方向切割开挖平面时随着节理数n的变化计算出一系列的结果点绘于图5中与n相应的稳定性因子的估计值也在图5中表示出来容易看出随着分割节理数目的降低这些估计值的大小降低到了均质化方法的估计值均质化方法和直接计算法的差异可以看成是由于尺寸效应而引起的而均质化方法并没有尺寸效应的问题为了设计上计算的省时高效克服直接计算法的局限同时要运用均质化的概念考虑对裂隙岩体介质采用一种新的描述方法Cosserat 或者是微极连续Biot 1967 Besdo 1985 Adhikary Dyskin 1997 以及 Sulem Mulhaus 1997 对于分层岩体或者是块体结构都有所描述本文的第二部分就是致力于应用这个模型来描述节理岩体介质的破坏特性安徽理工大学毕业论文1。

毕业设计外文文献翻译

毕业设计外文文献翻译Graduation Design Foreign Literature Translation (700 words) Title: The Impact of Artificial Intelligence on the Job Market Introduction:Artificial Intelligence (AI) is a rapidly growing field that has the potential to revolutionize various industries and job markets. With advancements in technologies such as machine learning and natural language processing, AI has become capable of performing tasks traditionally done by humans. This has raised concerns about the future of jobs and the impact AI will have on the job market. This literature review aims to explore the implications of AI on employment and job opportunities.AI in the Workplace:AI technologies are increasingly being integrated into the workplace, with the aim of automating routine and repetitive tasks. For example, automated chatbots are being used to handle customer service queries, while machine learning algorithms are being employed to analyze large data sets. This has resulted in increased efficiency and productivity in many industries. However, it has also led to concerns about job displacement and unemployment.Job Displacement:The rise of AI has raised concerns about job displacement, as AI technologies are becoming increasingly capable of performing tasks previously done by humans. For example, automated machines can now perform complex surgeries with greaterprecision than human surgeons. This has led to fears that certain jobs will become obsolete, leading to unemployment for those who were previously employed in these industries.New Job Opportunities:While AI might potentially replace certain jobs, it also creates new job opportunities. As AI technologies continue to evolve, there will be a greater demand for individuals with technical skills in AI development and programming. Additionally, jobs that require human interaction and emotional intelligence, such as social work or counseling, may become even more in demand, as they cannot be easily automated.Job Transformation:Another potential impact of AI on the job market is job transformation. AI technologies can augment human abilities rather than replacing them entirely. For example, AI-powered tools can assist professionals in making decisions, augmenting their expertise and productivity. This may result in changes in job roles and the need for individuals to adapt their skills to work alongside AI technologies.Conclusion:The impact of AI on the job market is still being studied and debated. While AI has the potential to automate certain tasks and potentially lead to job displacement, it also presents opportunities for new jobs and job transformation. It is essential for individuals and organizations to adapt and acquire the necessary skills to navigate these changes in order to stay competitive in the evolvingjob market. Further research is needed to fully understand the implications of AI on employment and job opportunities.。

三维动画设计外文翻译文献

文献信息：文献标题：Aesthetics and design in three dimensional animation process（三维动画过程中的美学与设计）国外作者：Gokce Kececi Sekeroglu文献出处：《Procedia - Social and Behavioral Sciences》, 2012 , 51 (6):812-817字数统计：英文2872单词，15380字符；中文4908汉字外文文献：Aesthetics and design in three dimensional animation processAbstract Since the end of the 20th century, animation techniques have been widely used in productions, advertisements, movies, commercials, credits, visual effects, and so on, and have become an indispensable part of the cinema and television. The fast growth of technology and its impact on all production industry has enabled computer-generated animation techniques to become varied and widespread. Computer animation techniques not only saves labour and money, but it also gives the producer the option of applying the technique in either two dimensional (2D) or three dimensional (3D), depending on the given time frame, scenario and content. In the 21st century cinema and television industry, computer animations have become more important than ever. Imaginary characters or objects, as well as people, events and places that are either difficult or costly, or even impossible to shoot, can now be produced and animated through computer modelling techniques. Nowadays, several sectors are benefiting from these specialised techniques. Increased demand and application areas have put the questions of aesthetics and design into perspective, hence introducing a new point of view to the application process. Coming out of necessity, 3D computer animations have added a new dimension to the field of art and design, and they have brought in the question of artistic and aesthetic value in such designs.Keywords: three dimension, animation, aesthetics, graphics, design, film1.IntroductionCenturies ago, ancient people not only expressed themselves by painting still images on cave surfaces, but they also attempted to convey motion regarding moments and events by painting images, which later helped establish the natural course of events in history. Such concern contributed greatly to the animation and cinema history.First examples of animation, which dates back approximately four centuries ago, represents milestones in history of cinema. Eadweard J. Muybridge took several photographs with multiple cameras (Figure 1) and assembled the individual images into a motion picture and invented the movie projector called Zoopraxiscope and with the projection he held in 1887 he was also regarded as the inventor of an early movie projector. In that aspect, Frenchmen Louis and Auguste Lumière brothers are often credited as inventing the first motion picture and the creator of cinematography (1895).Figure 1. Eadweard J. Muybridge’s first animated pictureJ. Stuart Blackton clearly recognised that the animated film could be a viable aesthetic and economic vehicle outside the context of orthodox live action cinema. Inparticular, his movie titled The Haunted Hotel (1907) included impressive supernatural sequences, and convinced audiences and financiers alike that the animated film had unlimited potential. (Wells, 1998:14)“Praxinoscope”- invented by Frenchman Charles-Émile Reynaud - is one of the motion picture related tools which was developed and improved in time, and the invention is considered to be the beginning of the history of animated films, in the modern sense of the word. At the beginning of the 20th century, animated films produced through hand-drawn animation technique proved very popular, and the world history was marked by the most recognisable cartoon characters in the world that were produced through these animations, such as Little Nemo (1911), Gertie the Dinosaur (1914), The Sinking of the Lusitania (1918), Little Red Riding Hood (1922), The Four Musicians of Bremen (1922) Mickey Mouse(1928), Snow White and the Seven Dwarfs (1937).Nazi regime in Germany leads to several important animation film productions. When Goebbels could no longer import Disney movies, he commissioned all animation studios to develop theatrical cartoons. Upon this, Hans Fischerkoesen began to produce animation films and by end of the war, he produced over a thousand cartoons (Moritz, 2003:320).In due course, animated films became increasingly popular, resulting in new and sizable sectors, and the advances in technology made expansion possible. From then on, the computer-generated productions, which thrived in the 1980's, snowballed into the indispensable part of the modern day television and cinema.The American animated movie Aladdin grossed over 495 million dollars worldwide, and represented the success of the American animation industry, which then led to an expansion into animated movies which targeted adults (Aydın, 2010:110).Japan is possibly just as assertive in the animation films as America. Following the success of the first Japanese animation (anime) called The White Snake Enchantress 1958 (Figure 2)which resulted in awards in Venice, Mexico and Berlin film festivals, Japanese animes became ever so popular, which led to continuousinternational success. For example, the movie titled Spirited Away won an Oscar for Best Animated Feature Film, and became the winner of the top prize at this year's Berlin film festival. Following their ever-increasing success in anime production, Japan became one of the most sought after hubs of animation industry by European and American companies interested in collaboration.Figure 2. The White Snake Enchantress 19582.Three Dimensional AnimationThe development of animation techniques, a process that can be traced back to the 18th century brought with it a thematic variety in animation genres. Today, animation techniques based on cartoons, puppets, stop-motion, shadow, cut-out and time lapse can be applied both manually and based on digital technology. Furthermore the use of 3D computer graphics in the 1976-dated film "Futureworld" opened the way for this technology to be in high demand in a variety of industries. 3D animations occupy a central role today in cinema, TV, education and video games alike, and their creative processes in both realistic and surreal terms seem to know no limits. This new medium that with its magical powers makes the impossible possible and defies the laws of physic (Gökçearslan, 2008: 1) open a door for designers and artists to anunlimited imagination. "In particular in the movies of the 80s, computer-aided animated effects turned out to be life-savers, and the feature film Terminator 2 (1991) in which 3D animation technology was used for the first time received praise from both audience and film critics" (Kaba, 1992: 19). Toy Story (Walt Disney Pictures, 1995), a film that became very popular among audiences of all ages due to its script, characters, settings and animation technique, was the first fully 3D animated feature film in history, and was followed by two sequels.By help of the support coming from the homeland, and its form oriented realistic format, Disney characters have been amongst the top animated characters. In order to achieve a realistic production, Disney even kept animals such as horses, deer, and rabbits in the studios, while the artists studied their form, movements and behaviour. As for human characters, famous movie stars of the period were hired as a reference point for human form and behaviour. (Gökçearslan, 2009:80).Another American movie "Shrek" (2001) created by William Steig, whose book Shrek (1990) formed basis for the DreamWorks Pictures full length 3D animation film, attracted millions of people. The movie is a great example of a clever and aesthetically pleasing combination of powerful imagination and realistic design. Also, by means of certain dialogues and jokes, the theme of "value judgement" is simplified in a way that it is also understood by children. These are amongst two undeniable factors which are thought to have contributed to the worldwide success of the movie.Most successful 3D animation movies are of American make. The importance of budget, historical and political factors, as well as contextual and stylistic factors which bring in simplicity and clarity to the movies is incontrovertible.“The era of the post-photographic film has arrived, and it is clear that for the animator, the computer is essentially "another pencil". Arguably, this has already reached its zenith in PIXAR's Monsters Inc. Consequently, it remains important to note that while Europe has retained a tradition of auteurist film making, also echoed elsewhere in Russia, China, and Japan, the United States has often immersed its animation within a Special Effects tradition, and as an adjunct to live action cinema.” (Wells, 2002:2).3.Aesthetics and Design in Three Dimensional AnimationsLow-budget and high-budget 3D animation movies go through the same process, regardless. This process is necessary in order to put several elements together properly.The first step is to write up a short text called synopsis, which aims to outline the movie plot, content and theme. Following the approval of the synopsis, the creative team moves on to storyboarding, where illustrations or images are displayed in sequence for the purpose of visualising the movie (Figure 3). Storyboarding process reflects 3D animator's perspective and the elements that are aimed to be conveyed to the audience. The animation artists give life to a scenario, and add a touch of their personality to the characters and environment. “"Gone With The Wind" is the first movie where the storyboarding technique, which was initially used in Walt Disney Studios during the production process of animated movies, was used for a non-animation movie, and since the 1940's, it has been an indispensible part of the film industry.Figure 3: Toy Story, storyboarding, PixarStory board artists are the staple of film industry, and they are the ones who either make or break the design and aesthetics of the movie. While they their mainresponsibility is to enframe the movie scenes with aesthetics and design quality in mind, they are also responsible for incorporating lights, shadows and colours in a way that it enhances the realistic features of the movie.The next step following storyboarding, is "timing" which is particularly important in determining the length of scenes, by taking the script into consideration. In order to achieve a realistic and plausible product, meticulous mathematical calculations are required.The next important step is to create characters and environment in 3D software, and finalise the production in accordance with the story-board. While character and objects are modelled in 3D software, such as 3Ds Max, Cinema 4D , Houdini, Maya, Lightwave, the background design is also created with digital art programs such as Photoshop, Illustrator, Artage, depending on the type or content of the movie (Figure: 4). Three dimensional modelling is the digital version of sculpturing. In time, with ever-changing technology, plastic arts have improved and become varied, leading to a new form of digital art, which also provides aesthetic integrity in terms of technique and content. Same as manually produced art work, 3D creations are also produced by highly skilled artist with extensive knowledge of anatomy, patterns, colours, textures, lights and composition. Such artists and designers are able to make use of their imagination and creativity, and take care of both technical and aesthetic aspects of creating an animated movie.Figure 4: Examples of 3D modelling (left) and background (right).In a movie, the colour, light and shadow elements affect the modelled character, setting and background to a very large extent. Three dimensional computer graphics software provides a realistic virtual studio and endless source of light combinations.Hence, the message and feeling is conveyed through an artistically sensitive and aesthetically pleasing atmosphere, created with a certain combination of light and colours. Spot light, omni, area and direct lights are a few examples to the types of options that can be used on their own or as a combination. For example, in 3D animations the 'direct light' source can be used outdoors as an alternative for the sun, whereas the 'area light' which uses vertical beams can help smooth out the surface by spreading the light around, which makes it ideal for indoors settings. Blue Sky Studio's 3D movie called “Ice Age” (Figure 5) produced in 2001 achieved a kind of unique and impressive technology-driven realistic technique with clever use of lights and colours, becoming one of the first exceedingly successful 3D animations of the period.Figure 5: “Ice Age”, Blue Sky Studios, 2001Following the modelling and finishing touches of other visual elements, each scene is animated one by one. “Actions assigned to each and every visual element within the scene have to have a meaningful connection with the story, in terms of form and content. In fact, the very fundamental principle of computer animations is that each action within the scene serves a certain purpose, and the design within the frame creates visual pleasure” . Underscoring element is also expected to complement the visuals and be in harmony with the scene. It is an accepted fact that a good visual is presented along with suitable music, affects the audience in emotional and logicalsense a lot more than it would have done so otherwise. For that reason, underscores are just as important as other audio elements, such as voiceovers and effects, when it comes to visual complements. Sound is an indispensable part of life and nature, therefore it can be considered as a fundamental means of storytelling. Clever and appropriate use of sound is very effective in maintaining the audience's attention and interest.In order to produce a meaningful final product in the editing phase, a careful process of storyboarding and timing have to be carried out. Skilfully executed editing can add rhythm and aesthetics to scenes. The integrity of time, setting, audio and atmosphere within a movie is also profusely important in terms of conveying the semantic rhythm. Meticulously timed fade-out, fade-in, radiance or smoke effects would allow the audience to follow the story more attentively and comfortably, and it would also establish consistency in terms of aesthetics of the movie itself.4. ConclusionNo matter how different the technological circumstances are today, and used to be back in the ancient times when humans painted images on cave surfaces, human beings have always been fascinated with visual communication. Since then, they have been striving to share their experiences, achievements, wishes and dreams with other people, societies or masses. For the same purpose, people have been painting, acting, writing plays, or producing movies. Incessant desire to convey a message through visual communication brought about the invention of the cinema, and since the 18th century, it has become an essential means of presenting ideas, thoughts or feelings to masses. 3D animations, which were mainly used in advertisements, commercials, education and entertainment related productions in the 2000's, brought about many blockbuster 3D movies.When recorded with a camera, the three dimensional aspect of reality is lost, and turned into two dimensions. In 3D animations, the aim is to emulate the reality and present the audience an experience as close to the real life as possible. “Human eye is much more advanced than a video camera. infinite sense of depth and the ability tofocus on several objects at the same time are only a few of many differences between a camera and the human eye. Computer-produced visuals would give the same results as the camera. Same as painting and photography, it aims to interpret the three dimensional world in a two dimensional form.” As a result, 3D animations have become just as important as real applications, and thanks to their ability to produce scenes that are very difficult, even impossible to emulate, they have actually become a better option. Big companies such as Walt Disney, Pixar, and Tree Star have been making 3D animations which appeal to both children and adults worldwide. Successful productions include the elements of appropriate ideas, decent content, combined with expert artists and designers with technical backgrounds. For that reason, in order to establish good quality visual communication and maintain the audience's attention, art and design must go hand in hand. Sometimes, being true to all the fundamental design principles may not be enough to achieve an aesthetically pleasing scene. In order to achieve an aesthetically pleasing scene, warmth and sincerity, which are typical attributes of human beings, must be incorporated into the movie. The modelling team, which functions as the sculptor and creates authentic materials like a painter, teams up with creative story-board artists, and texture and background artists, to achieve an artistically valuable work. In order to achieve plausibility and an aesthetically valuable creation, it is important that colour, light, shadow and textures used during the process are true to real life. Camera angles, speed and direction of movement, the sequence of the scenes and their harmony with the underscoring are essential in determining the schematic and aesthetic quality of a movie.In conclusion, Art does not teach. Rather, art presents the full and concrete reality of the end target. What art does is presents things "as they should be or could have been", which helps people attain such things in real life. However, this is just a secondary benefit of art. The main benefit of art is that it provides people with a taste of what "things would be like if they were the way they were supposed to be" in real life. Such an experience is essential to human life. Surely, people cannot watch a movie with the schematic or aesthetic quality of it in mind. However, as the movieprogresses, a visual language settles into the spectator's subconsciousness, creating a sense of pleasure. Walter Benjamin claims that a spectator analysing a picture is able to abandon himself to his associations. However, this is not the case for people watching a movie at the cinema. Rather, the cinema audience can only build associations after they have watched the movie, therefore the process of perception is delayed. (Benjamin, 1993:66).中文译文：三维动画过程中的美学与设计摘要自20世纪末以来，动画技术在生产、广告、电影、商业、节目、视觉效果等方面得到了广泛的应用，并已经成为影视业不可或缺的组成部分。

零件的三维建模及自动编程(内附中英文翻译)本科论文

本科毕业设计论文题目零件的三维建模及自动编程毕业任务书一、题目零件三维建模及自动编程二、指导思想和目的要求撰写毕业论文是检验学生在校学习成果的重要措施，也是提高教学质量的重要环节。

在毕业设计中，学生应独立承担一部分比较完整的工程技术设计任务。

要求学生发挥主观能动性，积极性和创造性，在毕业设计中着重培养独立工作能力和分析解决问题的能力，严谨踏实的工作作风，理论联系实际，以严谨认真的科学态度，进行有创造性的工作，认真、按时完成任务。

三、主要技术指标1.UG 三维建模文件一份2.UG 仿真加工文件一份3.NC 语句表一份四、进度和要求1—3周：查阅资料，确定设计方案，进行总体设计，熟悉相关软件4—5周：绘制零件三维图6周：校正零件三位图7—9周：对零件进行编程10周：完成数控仿真11—14周：撰写毕业论文15周：编写论文答辩PPT16周：准备学位论文答辩五、主要参考书及参考资料[1] 刘治映《毕业设计（论文）写作导论》.长沙：中南大学出版社.2006.6[2] 徐伟杨永《计算机辅助与制造》.高等教育出版社.2011.2[3] 于杰《数控加工与编程》. 北京：国防工业出版社.2009.1[4] 赵长明《数控加工工艺及设备》. 北京：高等教育出版社.2003.10.[5] 麓山文化《UG7从入门到精通》.北京：机械工业出版社2012,2[6] 朱焕池《机械制造工艺学》. 北京：机械工业出版社.2003.4设计论文[7] 李提仁《数控加工与编程技术》. 北京：北京大学出版社.2012.7[8] 焦小明《机械加工技术》. 北京：机械工业出版社.2005.7[9] 龚桂义《机械设计课程设计图册》（第三版).高等教育出版社.2010.[10] 薛顺源《机床夹具设计》.机械工业出版社，2001.[11] 肖继德陈宁平《机床夹具设计》.机械工业出版社，2002.[12] 张世昌《机械制造技术基础》.天津大学出版社，2002.[13] 刘建亭《机械制造基础》.机械工业出版社，2001.[14] 庄万玉丁杰雄《制造技术》.国防工业出版社，2005.[15] 韩鸿鸾，荣维芝《数控机床加工程序的编制》.北京：机械工业出版社.2002.12[16] 周湛学《机电工人识图及实例详解》.北京：化学工业出版社.2011.12[17] 施平《机械工程专业英语教程》.第二版.电子工业出版社.摘要数控编程是一种可编程的柔性加工方法，它的普及大大提高了加工效率。

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三维建模毕业答辩论文英文文献翻译
毕业设计(论文)
文献翻译
题目矿山测量三维模型制作学院测绘科学与技术学院专业测绘工程
班级0802班
学生史姝
学号0810020205
指导教师汤伏全
二〇一二年六月二日
Constructing Rules and Scheduling Technology for
3D Building Models
Zhengwei SUI, Lun WU, Jingnong WENG, Xing LIN, Xiaolu JI
Abstract
3D models have become important form of geographic data beyond conventional 2D geospatial data. Buildings are important marks for human to identify their environments, because they are close with human life, particularly in the urban areas. Geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. Architectural model data features with huge data volume, high complexity, non-uniform rules and so on. Hence, the cost of constructing large-scale scenes is high. Meanwhile, computers are lack of processing capacity upon a large number of model data. Therefore, resolving the conflicts between limited processing capacity of computer and massive data of model is valuable. By investigating the characteristics of buildings and the regular changes of viewpoint in virtual 3D environment, this article introduces several constructing rules and scheduling techniques for 3D constructing of buildings, aiming at the reduction of data volume and complexity of model and thus improving computers’ eff iciency at scheduling large amount of
architectural models. In order to evaluate the efficiency of proposed constructing rules and scheduling technology listed in the above text, the authors carry out a case study by 3D constructing the campus of Peking University using the proposed method and the traditional method. The two results are then examined and compared from aspects of model data volume, model factuality, speed of model loading, average responding time during visualization, compatibility and reusability in 3D geo-visualization platforms: China Star, one China’s own platform for 3D global GIS manufactured by the authors of this paper. The result of comparison reveals that models built by the proposed methods are much better than those built using traditional methods. For the constructing of building objects in large-scale scenes, the proposed methods can not only reduce the complexity and amount of model data remarkably, but can also improving computers’ efficiency.
Keywords: Constructing rules, Model scheduling, 3D buildings
I. INTRODUCTION
In recent years, with the development of 3D GIS (Geographical Information System) software like Google Earth, Skyline, NASA World Wind, large-scale 3D building models with regional characteristics have become important form of geographic data beyond conventional 2D geospatial data, like multi-resolution remote sensing images and vector data [1].Compared to traditional 2D representation, geographic information can be expressed in a more intuitive and effective manner with architectural models being modeled and visualized in a virtual 3D environment. 3D representation and visualization provides better visual effect and vivid urban geographic information, and thus plays an important role in people's perceptions of their environment. Meanwhile, the 3D building data is also of great significance for the construction of digital cities.
But how to efficiently visualize thousands of 3D building models in a virtual 3D environment is not a trivial question. The most difficult part of the question is the conflicts between limited processing capacity of computer and massive volume of model data, particularly in the procedure of model rendering. Taking the 3D modeling of a city for the example using traditional 3D modeling method, suppose there are 100 000 buildings to model in the urban area and the average size of model data for each building is roughly 10 M. So the total data volume of building models in the city could reach a TB level. However, the capacity of ordinary computer memory is only in the GB scale. Based on this concern, the authors proposed the scheduling technology for large-scale 3D buildings models in aspects of model loading and rendering. Due to the lack of building。