船舶设计外文文献翻译

合集下载

船舶专业外文翻译--船舶设计优化

船舶专业外文翻译一船舶设计优化Ship Design OptimizationThis contribution is devoted to exploiting the analogy between a modern manufacturing plant and a heterogeneous parallel computer to construct a HPCN decision support tool for ship designers. The application is a HPCN one because of the scale of shipbuilding ・ a large container vessel is constructed by assembling about 1.5 million atomic components in a production hierarchy. The role of the decision support tool is to rapidly evaluate the manufacturing consequences of design changes. The implementation as a distributed multi-agent application running on top of PVM is described1 Analogies between Manufacturing and HPCNThere are a number of analogies between the manufacture of complex products such as ships, aircraft and cars and the execution of a parallel program. The manufacture of a ship is carried out according to a production plan which ensures that all the components come together at the right time at the right place.A parallel computer application should ensure that the appropriate data is available on the appropriate processor in a timely fashion.It is not surprising, therefore, that manufacturing is plagued by indeterminacy exactly as are parallel programs executing on multi-processor hardware. This has caused a number of researchers in production engineering to seek inspiration in other areas where managing complexity and unpredictability is important. A number of new paradigms^ such as Holonic Manufacturing and Fractal Factories have emerged [1,2] which contain Ideas rather reminiscent of those to be found inthe field of Multi- Agent Systems [3,4].Manufacturing tasks are analogous to operations carried out on data, within the context of planning, scheduling and control. Also, complex products are assembled at physically distributed workshops or production facilities^ so the components must be transported between them. This is analogous to communication of data between processors in a parallel computer, which thus also makes clear the analogy between workshops and processors.The remainder of this paper reports an attempt to exploit this analogy to build a parallel application for optimizing ship design with regard to manufacturing issues.2 Shipbuilding at Odense Steel ShipyardOdense Steel Shipyard is situated in the town of Munkebo on the island of Funen. It is recognized as being one of the most modern and highly automated in the world. Itspecializes in building VLCC's (supertankers) and very large container ships. The yard was the first in the world to build a double hulled supertanker and is currently building an order of 15 of the largest container ships ever built for the Maersk line. These container ships are about 340 metres long and can carry about 7000 containers at a top speed of 28 knots with a crew of 12.Odense Steel Shipyard is more like a ship factory than a traditional shipyard. The ship design is broken down into manufacturing modules which are assembled and processed in a number of workshops devoted to, for example, cutting, welding and surface treatment. At any one time, up to 3 identical ships are being built and a new ship is launched about every 100 days.The yard survives in the very competitive world of shipbuilding by extensive application of information technology and robots, so there are currently about 40 robots at the yard engaged in various production activities. The yard has a coininitment to research as well, so that there are about 10 industrial Ph・D・students working there, who are enrolled at various engineering schools in Denmark.3 Tomorrow's Manufacturing SystemsThe penetration of Information Technology into our lives will also have its effect in manufacturing Industry. For example, the Internet is expected to becomethe dominant trading medium for goods. This means that the customer can come Into direct digital contact with the manufacturer.The direct digital contact with customers will enable them to participate in the design process so that they get a product over which they have some influence. The element of unpredictability introduced by taking into account customer desires increases the need for flexibility in the manufacturing process, especially in the light of the tendency towards globalization of productioiLIntelligent robot systems, such as AMROSE, rely on the digital CAD model as the primary source of information about the work piece and the work cell [5,6].This information is used to construct task performing, collision avoiding trajectories for the robots, which because of the high precision of the shipbuilding process, can be corrected for small deviations of the actual world from the virtual one using ven r simple sensor systems. The trajectories are generated by numerically solving the constrained equations of motion for a model of the robot moving in an artificial force field designed to attract the tool centre to the goal and repell it from obstacles, such as the work piece and parts of itself. Finally, there are limits to what one can get a robot to do, so the actual manufacturing will be performed as a collaboration between human and mechatronic agents.Most industrial products, such as the windmill housing component shown in Fig. 1, are designed electronically in a variety of CAD systems.Fig> 1. Showing the CAD model for the housing of a windmilL The model, made using Bentley Microstation, includes both the work-piece and task-curve geometries.4 Today v s Manufacturing SystemsThe above scenario should be compared to today's realities enforced by traditional production engineering philosophy based on the ideas of mass production introduced about 100 years ago by Henry Ford. A typical production line has the same structure as a serial computer program, so that the whole process is driven by production requirements. This rigidity is reflected on the types of top-down planning and control systems used in manufacturing industry, which are badly suited to both complexity and unpredictability.In fact, the manufacturing environment has always been characterized by unpredictability. Today's manufacturing systems are based on idealized models where unpredictability is not taken into account but handled using complex and expensive logistics and buffering systems.Manufacturers are also becoming aware that one of the results of the top-down serial approach is an alienation of human workers. For example, some of the car manufacturers have experimented with having teams of human workers responsible for a particular car rather than performing repetitive operations in a production line. This model in fact better reflects the concurrency of the manufacturing process than the assembly line.5 A Decision Support Tool for Ship Design OptimizationLarge ships are, together with aircraft, some of the most complex things ever built A container ship consists of about 1.5 million atomic components which are assembled in a hierarchy of increasingly complex components. Thus any support tool for the manufacturing process can be expected to be a large HPCN application.Ships are designed with both functionality and ease of construction in mind, as well as issues such as economy, safety, insurance issues, maintenance and even decommissioning. Once a functional design is in place, a stepwise decomposition of the overall design into a hierarchy of manufacturing components is performed. The manufacturing process then starts with the individual basic building blocks such as steel plates and pipes. These building blocks are put together into ever more complex structures and finally assembled in the dock to form the flnished ship.Thus a very useful thing to know as soon as possible after design time are the manufacturing consequences of design decisions. This includes issues such as whether the intermediate structures can actually be built bv the availableproduction facilities, the implications on the use of material and whether or not the production can be efficiently scheduled [7].Fig.2. shows schematically how a redesign decision at a point in time during construction implies future costs, only some of which are known at the time. Thus a decision support tool is required to give better estimates of the implied costs as early as possible in the process.Simulation，both of the feasibility of the manufacturing tasks and the efficiency with which these tasks can be performed using the available equipment, is a very compute-intense application of simulation and optimization. In the next section, we describe how a decision support tool can be designed and implemented as a parallel application by modeling the main actors in the process as agents.Fig>2> Economic consequences of design decisions. A design decision implies a future commitment of economic resources which is only partially known at design time.6 Multi-Agent SystemsThe notion of a software agent, a sort of autonomous, dynamic generalization of an object (in the sense of Object Orientation) is probably unfamiliar to the typical HPCN reader in the area of scientific computation. An agent possesses its own beliefs, desires and intentions and is able to reason about and act oil its perceptionof other agents and the environment.A multi-agent system is a collection of agents which try to cooperate to solve some problem, typically in the areas of control and optimization. A good example is the process of learning to drive a car in traffic. Each driver is an autonomous agent which observes and reasons about the intentions of other drivers. Agents are in fact a very useful tool for modeling a wide range of dynamical processes in the real worlds such as the motion of protein molecules [8] or multi-link robots [9]. For other applications, see [4].One of the interesting properties of multi-agent systems is the way global behavior of the system emerges from the individual interactions of the agents [10]. The notion of emergence can be thought of as generalizing the concept of evolution in dynamical systems.Examples of agents present in the system are the assembly network generator agent which encapsulates knowledge about shipbuilding production methods for planning assembly sequences, the robot motion verification agent, which is a simulator capable of generating collision-free trajectories for robots carrying out their tasks, the quantity surveyor agent which possesses knowledge about various costs involved in the manufacturing process and the scheduling agent which designs a schedule for performing the manufacturing tasks using the production resources available.7 Parallel ImplementationThe decision support tool which implements all these agents is a piece of Object- Oriented software targeted at a multi-processor system, in this case, a network of Silicon Graphics workstations in the Design Department at Odense Steel Shipyard. Rather than hand-code all the communication between agents and meta-code for load balancing the parallel application, abstract interaction mechanisms were developed. These mechanisms are based on a task distribution agent being present on each processor. The society of task distribution agents is responsible for all aspects of communication and migration of tasks in the system.The overall agent system runs on top of PVM and achieves good speedup and load balancing. To give some idea of the size of the shipbuilding application^ it takes 7 hours to evaluate a single design on 25 SGI workstations.From：Applied Parallel Computing Large Scale Scientific and Industrial Problems LectureNotes in Computer Science, 1998, Volume1541/199& 476-482, DOI: 10.1007/BFb0095371.中文翻译：船舶设计优化这一贡献致力于开拓类比现代先进制造工厂和一个异构并行计算机，构建了一种HPCN决策支援工具给船舶设计师。

船舶设计英文翻译

商船类型杂贷船杂货船的船内空间沿纵向被横舱壁分隔成一系列舱容大致相等的货舱，其舱壁间距为40～70英尺。

垂线间长约为500英尺的船舶一般分成七个货舱。

垂直方向上，最上层连续甲板(主甲板或强力甲板)以下的舱壁用一、二层甲扳分隔开。

内底和最下层甲扳之间的空间称为货舱，其空间高度限制在18英尺以内，为的是使货物压损减少到最小程度。

每层甲板间(称为甲板间舱)高度通常为9~10英尺。

大多数杂货船，除了有上述的双层底舱以外，还设有深舱，用作存放燃油、压截水或如胶乳、椰子油或食用油这一类液体货物。

货物是通过每一个货舱上方甲板的矩形大开口(舱口)来进行装卸的。

一般采用机动的舱口盖来关闭舱口．甲板间舱的舱口盖结构应该足够牢固，以便使它能够承受压在其上面的货物。

顶舱盖应该水密。

甲板间舱的空间一般适宜于装卸件杂货物或用贷盘托运的货物。

通常载货舱在每一层甲板上设有一个舱口，其宽度为船宽的35~50％，长度为舱长的50~60％。

为了加快货物装卸速度，舱口布置的倾向是越来越宽或横向有多个并排舱口，而且舱口也变得更长。

横向采用并排多只舱口布置(例如，三只舱口并排)，可以提高位于甲板下面的集装箱的装卸效率。

码头和船舶之间件杂货物的装卸通常是通过安装在船舶甲板上的吊货杆来进行的。

吊杆的起落靠从桅杆或吊杆柱通到吊杆顶端的可调节索具来进行控制，而另一根绳索从绞车到每一吊杆的顶端绕过滑轮在吊货钩处终止。

起货可以用一根吊杆(通常用来吊10吨以上的重贷)；快速装卸时，可采用一对联台吊杆，一吊杆端在舱口的上方，另一吊杆端在码头上方。

这种货物装卸怍业称为双杆联台操作，一般用于10吨以下的货物。

大多数安装有吊杆的件杂货船在每一舱口端都设有一对吊杆以加速货物装卸。

通常把货物一起堆在一只大网袋里，网袋出空后又返回进行下一次装卸。

尺寸几乎相同的包装货物可堆在货盘上，而后整个货盘被吊殉船上。

吊起的货物通过舱口降下，然后从同袋里或货盘上卸货，每一组货物的理货工人一件件分别贮存好。

（完整版）船舶专业英语（课文+翻译）

（完整版）船舶专业英语（课文+翻译）Chapter 1 Ship Design（船舶设计）Lesson 2 Ships Categorized（船舶分类）2.1 Introduction（介绍）The forms a ship can take are innumerable. 一艘船能采用的外形是不可胜数的A vessel might appear to be a sleek seagoing hotel carrying passengers along to some exotic destination; a floating fortress bristling with missile launchers; 。

or an elongated box transporting tanks of crude oil and topped with complex pipe connections. 一艘船可以看做是将乘客一直运送到外国目的地的优美的远航宾馆。

竖立有导弹发射架的水面堡垒及甲板上铺盖有复杂管系的加长罐装原油运输轮None of these descriptions of external appearance, however, does justice to the ship system as a whole and integrated unit所有这些外部特点的描述都不能说明船舶系统是一个总的集合体self-sufficient,seaworthy, and adequately stable in its function as a secure habitat for crew and cargo. ——船员和货物的安全性功能：自给自足，适航，足够稳定。

This is the concept that the naval architect keeps in mind when designing the ship and that provides the basis for subsequent discussions, not only in this chapter but throughout the entire book.这是一个造船工程师设计船舶使必须记住的、能为以后讨论提供根据的观念，不仅涉及本章也贯穿全书。

船舶设计论文中英文外文翻译文献

船舶设计论文中英文外文翻译文献XXX shipbuilding。

with a single large container vessel consisting of approximately 1.5 n atomic components in a n hierarchy。

this n is considered a XXX involves a distributed multi-agent n that runs on top of PVM.2 XXXShip XXX process。

as well as the final product's performance and safety。

nal design XXX-consuming and often fail to consider all the complex factors XXX。

there is a need for a more XXX designers.3 The Role of HPCN in Ship Design nHPCN。

or high-performance computing and orking。

has the potential to XXX utilizing the massive parallel processing power of HPCN。

designers XXX changes。

cing the time and cost of thedesign process。

nally。

HPCN can handle the complex XXX。

XXX.4 XXX XXX of the HPCN n Support ToolThe XXX ship designers is implemented as a distributed multi-agent n that runs on top of PVM。

船舶专业外文文献

Spatial scheduling for large assembly blocks inshipbuildingAbstract：This paper addresses the spatial scheduling problem （SPP）for large assembly blocks，which arises in a shipyard assembly shop。

The spatial scheduling problem is to schedule a set of jobs, of which each requires its physical space in a restricted space。

This problem is complicated because both the scheduling of assemblies with different due dates and earliest starting times and the spatial allocation of blocks with different sizes and loads must be considered simultaneously。

This problem under consideration aims to the minimization of both the makespan and the load balance and includes various real-world constraints，which includes the possible directional rotation of blocks，the existence of symmetric blocks, and the assignment of some blocks to designated workplaces or work teams. The problem is formulated as a mixed integer programming (MIP）model and solved by a commercially available solver. A two-stage heuristic algorithm has been developed to use dispatching priority rules and a diagonal fill space allocation method，which is a modification of bottom-left-fill space allocation method。

(完整版)船舶专业英语(课文+翻译)

Chapter 1 Ship Design（船舶设计）Lesson 2 Ships Categorized（船舶分类）2.1 Introduction（介绍）The forms a ship can take are innumerable. 一艘船能采用的外形是不可胜数的A vessel might appear to be a sleek seagoing hotel carrying passengers along to some exotic destination; a floating fortress bristling with missile launchers; 。

or an elongated box transporting tanks of crude oil and topped with complex pipe connections. 一艘船可以看做是将乘客一直运送到外国目的地的优美的远航宾馆。

船舶专业英语(课文+翻译)

Chapter 1 Ship Design（船舶设计）Lesson 2 Ships Categorized（船舶分类）Introduction（介绍）The forms a ship can take are innumerable. 一艘船能采用的外形是不可胜数的A vessel might appear to be a sleek seagoing hotel carrying passengers along to some exotic destination; a floating fortress bristling with missile launchers; 。

or an elongated box transporting tanks of crude oil and topped with complex pipe connections. 一艘船可以看做是将乘客一直运送到外国目的地的优美的远航宾馆。

竖立有导弹发射架的水面堡垒及甲板上铺盖有复杂管系的加长罐装原油运输轮None of these descriptions of external appearance, however, does justice to the ship system as a whole and integrated unit所有这些外部特点的描述都不能说明船舶系统是一个总的集合体—self-sufficient,seaworthy, and adequately stable in its function as a secure habitat for crew and cargo. ——船员和货物的安全性功能：自给自足，适航，足够稳定。

船舶设计外文翻译---船舶最大下沉量

The Maximum Sinkage of a ShipT. P. Gourlay and E. O. TuckDepartment of Applied Mathematics, TheUniversity of Adelaide, AustraliaA ship moving steadily forward in shallow water of constant depth h is usually subject to downward forces and hence squat, which is a potentially dangerous sinkage or increase in draft. Sinkage increases with ship speed, until it reaches a maximum at just below the critical speedHere we use both a linear transcritical shallow-water equation and a fully dispersive finite-depth theory to discuss the flow near that critical speed and to compute the maximum sinkage, trim angle, and stern displacement for some example hulls.IntroductionFor a thin vertical-sided obstruction extending from bottom to top of a shallow stream of depth h and infinite width, Michell (1898) showed that the small disturbance velocity potential φ(x,y)satisfies the linearized equation of shallow-water theory(SWT)yy 0xx βφ + φ= (1)Where 2F h β=1-, with F =U /h x -wise stream velocity U and water depth h . This is the same equation that describes linearized aerodynamic flow past a thin airfoil (see e.g., Newman 1977 p. 375), with F h replacing the Mach number. For a slender ship of a general cross-sectionalshape, Tuck (1966) showed that equation (1) is to be solved subject to a body boundary condition of the form'US ()(x,0)=2y x h ±Φ± (2)where S(x) is the ship’s submerged cross -section area at station x . The boundary condition (2) indicates that the ship behaves in the (x ,y) horizontal plane as if it were a symmetric thin airfoil whose thickness S(x)/h is obtained by averaging the ship’s cross -section thickness over the water depth. There are also boundaryconditions at infinity, essentially that the disturbance velocity ∇Φ vanishes in subcritical flow(0β<).As in aerodynamics, the solution of (1) is straightforward for either fully subcritical flow (where it is elliptic) or fully supercritical flow (where it is hyperbolic). In either case, the solutionhas a singularity as 0β→, or F 1h →.In particular the subcritical (positive upward) force isgiven by Tuck (1966) as2F =B'(x)S'()log dxd x ξξξ- (3)with B(x) the local beam at station x . Here and subsequently the integrations are over the wetted length of the ship, i.e.,22L L X -<<where L is the ship’s waterline length. This force F is usually negative, i.e., downward, and for a fore-aft symmetric ship, theresulting midship sinkage is given hydrostatically by22S V s C L ⎛⎫= ⎪⎝⎭ (4) where ()V S x dx =⎰is the ship’s displaced volume, and2'()'()log 2s W L C dxd B x S x A Vξξξπ=-⎰⎰ (5) where ()w A B x dx =⎰is the ship’s waterplane area. The nondimensional coefficient 1.4s C ≈ has been shown by Tuck &Taylor(1970) to be almost a universal constant, depending only weakly on the ship’s hull shape.Hence the sinkage appears according to this linear dispersionless theory to tend to infinity as 1h F →.However, in practice, there are dispersive effects near 1h F = which limit the sinkage, and which cause it to reach a maximum value at just below the critical speed.Accurate full-scale experimental data for maximum sinkage are scarce. However,, according to linear inviscid theory, the maximum sinkage is directly proportional to the ship length for a given shape of ship and depth-to-draft ratio (see later). This means that model experiments for maximum sinkage (e.g., Graff et al 1964) can be scaled proportionally to length to yield full-scale results, provided the depth-to-draft ratio remains the same.The magnitude of this maximum sinkage is considerable. For example, the Taylor Series A3 model studied by Graff et al (1964) had a maximum sinkage of 0.89% of the ship length for the depth-to-draft ratio h/T = 4.0. This corresponds to a midship sinkage of 1.88 meters for a 200 meter ship. Experiments on maximum squat were also performed by Du & Millward (1991) using NPL round bilge series hulls. They obtained a maximum midship sinkage of 1.4% of the ship length for model 150B with h/T =2.3. This corresponds to 2.8 meters midship sinkage for a 200 meter ship. Taking into account the fact that there is usually a significant bow-up trim angle at the speed where the maximum sinkage occurs, the downward displacement of the stern can be even greater, of the order of 4 meters or more for a 200-meter long ship.It is important to note that only ships that are capable of traveling at transcritical Froude numbers will ever reach this maximum sinkage. Therefore, maximum sinkage predictions will be less relevant for slower ships such as tankers or bulk carriers. Since the ships or catamarans that frequently travel at transcritical Froude numbers are usually comparatively slender, we expect that slender-body theory will provide good results for the maximum sinkage of these ships.For ships traveling in channels, the width of the channel becomes increasingly importantaround 1h F =when the flow is unsteady and solitons are emitted forward of the ship (see e.g.,Wu& Wu 1982). Hence experiments performed in channels cannot be used to accurately predict maximum sinkage for ships in open water. The experiments of Graff et al were done in a wide tank, approximately 36 times the model beam, and are the best results available with which to compare an open-water theory. However, even with this large tank width, sidewalls still affect the flow near 1h F =, as we shall discuss.Transcritical shallow-water theory (TSWT)It is not possible simply to set ‚0β= in (1) in order to gain useful information about the flow near 1h F =. As with transonic aerodynamics, it is necessary to include other terms that have been neglected in the linearized derivation of SWT (1).An approach suggested by Mei (1976) (see also Mei & Choi,1987) is to derive an evolution equation of Korteweg-de Varies (KdV) type for the flow near 1h F =. The usual one-dimensional forms of such equations contain both nonlinear and dispersive terms. It is not difficult to incorporate the second space dimension y into the derivation, resulting in a two-dimensional KdV equation, which generalizes (1) by adding two terms to give231h 03xx yy X XX xxxx U βΦ+Φ-ΦΦ+Φ= (6) The nonlinear term in X XX ΦΦbut not the dispersive term inxxxx Φwas included by Lea & Feldman (1972). Further solutions of this nonlinear but nondispersive equation were obtained by Ang (1993) for a ship in a channel. Chen & Sharma (1995) considered the unsteady problem of soliton generation by a ship in a channel, using the Kadomtsev-Petviashvili equation, which is essentially an unsteady version of equation (6). Although they concentrated on finite-width domains, their method is also applicable to open water, albeit computationally intensive. Further nonlinear and dispersive terms were included by Chen (1999), allowing finite-width results to be computed over a larger range of Froude numbers.Mei (1976) considered the full equation (6) in open water and provided an analytic solution for the linear case where the term X XX ΦΦis omitted. He showed that for sufficiently slender ships the nonlinear term in equation (6) is of less importance than the dispersive term and can be neglected; also that the reverse is true for full-form ships where the nonlinear term is dominant. This is also discussed in Gourlay (2000).As stated earlier, most ships that are capable of traveling at transcritical speeds are comparatively slender. For these ships it is dispersion, not nonlinearity, that limits the sinkage in open water. Nonlinearity is usually included in one-dimensional KdV equations by necessity, as a steepening agent to provide a balance to the broadening effect of the dispersive term in xxxx Φ.Inopen water, however, there is already an adequate balance with the two-dimensional term in yyΦ.This is in contrast to finite-width domains, which tend to amplify transcritical effects and cause the flow to be more nearly unidirectional. Hence nonlinearity becomes important in finite-width channels to such an extent that steady flow becomes impossible in a narrow range of speeds close to critical (see e.g., Constantine 1961, Wu & Wu 1982).Therefore, for slender ships in shallow water of large or in finite width, we can solve for maximum squat using the simple transcritical shallow-water (TSWT) equation0xx yy xxxx βγΦ+Φ+Φ= (7) (Writing23h γ=), subject to the same boundary condition (2). The term in ƒ provides dispersion that was absent in the SWT,and limits the maximum sinkage.ConclusionsWe have used two slender-body methods to solve for the sinkage and trim of a ship traveling at arbitrary Froude number, including the transcritical region.The transcritical shallow water theory (TSWT) developed by Mei (1976) has been extended and exploited numerically, using numerical Fourier transform methods to give sinkage and trim via a double numerical integration. This theory has also been extended to the case of a ship moving in a channel of finite width; however, the numerical difficulty in computing the resulting force integral, and its limited validity, mean that the open-water theory is more practically useful.The finite-depth theory (FDT) developed by Tuck & Taylor (1970) has also been improved and used for general hull shapes. This theory gives a sinkage force and trim moment that are slightly oscillatory in h F . Since the theory involves summing infinite-depth and finite-depthcontributions, both of which vary with 2U at high Froude numbers, any error will growapproximately quadratically with U . Therefore we cannot use this theory at large supercritical Froude numbers. Also, the difficulty in finding the infinite-depth contributions numerically, as well as the extra numerical integration needed to compute the force and moment, make the FDT slightly more dif. cult to implement than TSWT.In practice, scenarios in which ships are at risk of grounding will normally have h/L <0.125. Since the TSWT is a shallow water theory and it works well at h/L = 0.125, we expect that it will give even better results at smaller, practically useful values of h=L . Also, since the TSWT and FDT give almost identical results for h/L <0.125, and the TSWT is a much simpler theory, we recommend it as a simple and accurate method for predicting transcritical squat in open water.备注：T.P.Gourlay and E.O.Tuck ．The Maximum Sinkage of a ship[J]．Jourmal of Ship Research ，2001．50~58<文献翻译二：译文>船舶最大下沉量T. P. Gourlay and E. O. Tuck澳大利亚阿德莱德大学一艘在等深为h 的浅水中平稳前行的船舶通常趋向于受到向下的合力并产生船体下沉,处我们同时利用”线性跨临界浅水方程”和”完全分散限深理论”研究典型船体在接近临界速度时的水流和计算这些船体的最大下沉量、纵倾角和船尾位移。

船舶设计论文中英文外文翻译文献

中英文外文翻译文献Ship Design OptimizationThis contribution is devoted to exploiting the analogy between a modern manufacturing plant and a heterogeneous parallel computer to construct a HPCN decision support tool for ship designers. The application is a HPCN one because of the scale of shipbuilding - a large container vessel is constructed by assembling about 1.5 million atomic components in a production hierarchy. The role of the decision support tool is to rapidly evaluate the manufacturing consequences of design changes. The implementation as a distributed multi-agent application running on top of PVM is described1 Analogies between Manufacturing and HPCNThere are a number of analogies between the manufacture of complex products such as ships, aircraft and cars and the execution of a parallel program. The manufacture of a ship is carried out according to a production plan which ensures that all the components come together at the right time at the right place. A parallel computer application should ensure that the appropriate data is available on the appropriate processor in a timely fashion.It is not surprising, therefore, that manufacturing is plagued by indeterminacy exactly as are parallel programs executing on multi-processor hardware. This has caused a number of researchers in production engineering to seek inspiration in otherareas where managing complexity and unpredictability is important. A number of new paradigms, such as Holonic Manufacturing and Fractal Factories have emerged [1,2] which contain ideas rather reminiscent of those to be found in the field of Multi- Agent Systems [3, 4].Manufacturing tasks are analogous to operations carried out on data, within the context of planning, scheduling and control. Also, complex products are assembled at physically distributed workshops or production facilities, so the components must be transported between them. This is analogous to communication of data between processors in a parallel computer, which thus also makes clear the analogy between workshops and processors.The remainder of this paper reports an attempt to exploit this analogy to build a parallel application for optimizing ship design with regard to manufacturing issues.2 Shipbuilding at Odense Steel ShipyardOdense Steel Shipyard is situated in the town of Munkebo on the island of Funen. It is recognized as being one of the most modern and highly automated in the world. It specializes in building VLCC's (supertankers) and very large container ships. The yard was the first in the world to build a double hulled supertanker and is currently building an order of 15 of the largest container ships ever built for the Maersk line. These container ships are about 340 metres long and can carry about 7000 containers at a top speed of 28 knots with a crew of 12.Odense Steel Shipyard is more like a ship factory than a traditional shipyard. The ship design is broken down into manufacturing modules which are assembled and processed in a number of workshops devoted to, for example, cutting, welding and surface treatment. At any one time, up to 3 identical ships are being built and a new ship is launched about every 100 days.The yard survives in the very competitive world of shipbuilding by extensive application of information technology and robots, so there are currently about 40 robots at the yard engaged in various production activities. The yard has a commitment to research as well, so that there are about 10 industrial Ph.D. students working there, who are enrolled at various engineering schools in Denmark.3 Tomorrow's Manufacturing SystemsThe penetration of Information Technology into our lives will also have its effect in manufacturing industry. For example, the Internet is expected to become thedominant trading medium for goods. This means that the customer can come into direct digital contact with the manufacturer.The direct digital contact with customers will enable them to participate in the design process so that they get a product over which they have some influence. The element of unpredictability introduced by taking into account customer desires increases the need for flexibility in the manufacturing process, especially in the light of the tendency towards globalization of production. Intelligent robot systems, such as AMROSE, rely on the digital CAD model as the primary source of information about the work piece and the work cell [5,6].This information is used to construct task performing, collision avoiding trajectories for the robots, which because of the high precision of the shipbuilding process, can be corrected for small deviations of the actual world from the virtual one using very simple sensor systems. The trajectories are generated by numerically solving the constrained equations of motion for a model of the robot moving in an artificial force field designed to attract the tool centre to the goal and repell it from obstacles, such as the work piece and parts of itself. Finally, there are limits to what one can get a robot to do, so the actual manufacturing will be performed as a collaboration between human and mechatronic agents.Most industrial products, such as the windmill housing component shown in Fig. 1, are designed electronically in a variety of CAD systems.Fig. 1. Showing the CAD model for the housing of a windmill. The model, made using Bentley Microstation, includes both the work-piece and task-curve geometries.4 Today's Manufacturing SystemsThe above scenario should be compared to today's realities enforced by traditional production engineering philosophy based on the ideas of mass production introduced about 100 years ago by Henry Ford. A typical production line has the same structure as a serial computer program, so that the whole process is driven by production requirements. This rigidity is reflected on the types of top-down planning and control systems used in manufacturing industry, which are badly suited to both complexity and unpredictability.In fact, the manufacturing environment has always been characterized by unpredictability. Today's manufacturing systems are based on idealized models where unpredictability is not taken into account but handled using complex and expensive logistics and buffering systems.Manufacturers are also becoming aware that one of the results of the top-down serial approach is an alienation of human workers. For example, some of the car manufacturers have experimented with having teams of human workers responsible for a particular car rather than performing repetitive operations in a production line. This model in fact better reflects the concurrency of the manufacturing process than the assembly line.5 A Decision Support Tool for Ship Design OptimizationLarge ships are, together with aircraft, some of the most complex things ever built. A container ship consists of about 1.5 million atomic components which are assembled in a hierarchy of increasingly complex components. Thus any support tool for the manufacturing process can be expected to be a large HPCN application.Ships are designed with both functionality and ease of construction in mind, as well as issues such as economy, safety, insurance issues, maintenance and even decommissioning. Once a functional design is in place, a stepwise decomposition of the overall design into a hierarchy of manufacturing components is performed. The manufacturing process then starts with the individual basic building blocks such as steel plates and pipes. These building blocks are put together into ever more complex structures and finally assembled in the dock to form the finished ship.Thus a very useful thing to know as soon as possible after design time are the manufacturing consequences of design decisions. This includes issues such as whether the intermediate structures can actually be built by the available production facilities, the implications on the use of material and whether or not the production can be efficiently scheduled [7].Fig.2. shows schematically how a redesign decision at a point in time during construction implies future costs, only some of which are known at the time. Thus a decision support tool is required to give better estimates of the implied costs as early as possible in the process.Simulation, both of the feasibility of the manufacturing tasks and the efficiency with which these tasks can be performed using the available equipment, is a very compute-intense application of simulation and optimization. In the next section, we describe how a decision support tool can be designed and implemented as a parallel application by modeling the main actors in the process as agents.Fig.2. Economic consequences of design decisions. A design decision implies a future commitment of economic resources which is only partially known at design time.6 Multi-Agent SystemsThe notion of a software agent, a sort of autonomous, dynamic generalization of an object (in the sense of Object Orientation) is probably unfamiliar to the typical HPCN reader in the area of scientific computation. An agent possesses its own beliefs, desires and intentions and is able to reason about and act on its perception of other agents and the environment.A multi-agent system is a collection of agents which try to cooperate to solve some problem, typically in the areas of control and optimization. A good example is the process of learning to drive a car in traffic. Each driver is an autonomous agent which observes and reasons about the intentions of other drivers. Agents are in fact a very useful tool for modeling a wide range of dynamical processes in the real world, such as the motion of protein molecules [8] or multi-link robots [9]. For other applications, see [4].One of the interesting properties of multi-agent systems is the way global behavior of the system emerges from the individual interactions of the agents [10]. The notion of emergence can be thought of as generalizing the concept of evolution in dynamical systems.Examples of agents present in the system are the assembly network generator agent which encapsulates knowledge about shipbuilding production methods for planning assembly sequences, the robot motion verification agent, which is a simulator capable of generating collision-free trajectories for robots carrying out their tasks, the quantity surveyor agent which possesses knowledge about various costs involved in the manufacturing process and the scheduling agent which designs a schedule for performing the manufacturing tasks using the production resources available.7 Parallel ImplementationThe decision support tool which implements all these agents is a piece of Object- Oriented software targeted at a multi-processor system, in this case, a network of Silicon Graphics workstations in the Design Department at Odense Steel Shipyard. Rather than hand-code all the communication between agents and meta-code for load balancing the parallel application, abstract interaction mechanisms were developed. These mechanisms are based on a task distribution agent being present on each processor. The society of task distribution agents is responsible for all aspects of communication and migration of tasks in the system.The overall agent system runs on top of PVM and achieves good speedup andload balancing. To give some idea of the size of the shipbuilding application, it takes 7 hours to evaluate a single design on 25 SGI workstations.From：Applied Parallel Computing Large Scale Scientific and Industrial Problems Lecture Notes in Computer Science, 1998, Volume 1541/1998, 476-482, DOI: 10.1007/BFb0095371 .中文翻译：船舶设计优化这一贡献致力于开拓类比现代先进制造工厂和一个异构并行计算机,构建了一种HPCN 决策支援工具给船舶设计师。

船舶论文外文翻译

1.1Container Shipping ChangesAs commerce has become and continues to be more international, ocean container shipments have grown exponentially as a means of moving most any kind of freight from one port to another. Buffered by waves of change touching other modes of transport, ocean carriers are in a constant process of altering the way they conduct their business to meet current needs of shipping customers. While chartered to serve a wider public with insight about the industry, the Container Shipping Information Service (CSIS) is able to provide a spokesperson from one of its 24 member companies to treat objectively with commonly shared issues. Andres Kulka, senior vice president of CSAV Group North America shares just such insights.In an environment of high transportation costs, ocean container shipping‟s mix of speed, cost, availability and capability offers a superior value proposition, especially as logistics and supply chain management processes and systems are implemented by a growing range of shippers. Because of their shelf life or time value certain commodities must be transported by air. Increases in the need to speedily transport these commodities along with the greater economy will be a primary factor for airfreight growth in the future. But spiraling fuel surcharges and resulting cost consciousness among shippers opens opportunities for ocean carriers to gain market share in the broader spectrum of non- perishable commodities where airfreight‟s cost effectiveness has diminished.Shortages of containers is produced by commercial imbalance situations. When exports outgrow imports in a geographic region, you may face equipment shortages, as was the case in Asia. When you add imbalance by type of equipment to the situation, the situation worsens. While at present leasing containers are available to meet the demand in Asia, container pricing has reached levels of $2,500 for a dry,due largely, to the increase of commodities costs and deterioration of the US exchangeThere have been reports of shortages of containers, particularly for cargo moving from Asia.Under these conditions,shipping lines are relying primarily on empty repositioning to Asia rather than use of fresh equipment.The shortage of equipment in the US today is due to two primary factors. First,exports are growing at high rates, mainly because of devaluation of the USdollar.Additionally imports are pretty much staggered causing, again, a commercial imbalance. Secondly, last year many nonprofitable international intermodal lanes were eliminated. This reduced the stock of containers at some inland locations available for exports.Location specific equipment shortages have created the need for increasing empty container repositioning. That is one of the reasons export freight rates have gone up. Media pays great attention to Asian business, but how healthy is container shipping in other regions, say Latin America?In fact trade with Latin America has been sensitive to the sharp fall of theUS dollar. For example in 2007 the Brazilian real was down 17% and the Chilean peso fell 7%. For exports total 2007 volumes for Latin America were about 800,000 TEU (twenty-foot equivalent units), approximately 20% greater than 2006. Top commodities exported to Latin America have been resins,chemicals, plastics, forest products and general merchandise. Higher rates have followed the increase in export demand.Foodstuffs and forest products dominate import volumes from South America, about 970,000 TEU in 2007. Unlike exports, import volume growth—5.5% greater than 2006—has slowed due to the decline of the US dollar. Import rates have risen, but not nearly as strongly as export rates. So far in 2008 the US dollar has continued its downward trend. We are very cautious about the future outlook. Even though exports will probably continue growing at high rates, imports might continue decreasing.1.2Discussion of Structural Standards DevelopmentTaken as a whole, there has been a piecemeal approach to structural design standards. As technical developments occur (models of various structural behaviours, risk methodologies), they have been incorporated into structural standards. Individuals and rule committees have framed their own rules with an emphasis on certain load/strength/failure models, coupled with some risk avoidance strategy (explicit or implicit). It is hardly surprising that various standards are different, even quite different. More,rather than fewer, concepts are available to those who develop structural standards. In the absence of a binding philosophy of structural behaviour, there will continue to be divergence along the way to improved standards. It must be appreciated that all current standards “work”. Any of the current naval and commercial ship design approaches can be used to produce structural designs that function with adequate reliability over a 20+ yearlife expectancy, unless subjected to poor maintenance, human operational error, or deliberate damage. Changes to standards are, therefore, resisted by all those who have invested time and effort in them as developers and users. The rationale for change must be presented well, and its benefits have to outweigh its costs.Experienced designers recognize that structural behaviour can be very complex. Despite this, it is necessary to use simple, practical approaches in design standards, to avoid adding to the problem through overly-complex rules that are difficult to apply and more so to check and audit. Stress is the primary load-effect that standards focus on, partly because it is so readily calculated. The main concerns are material yielding, buckling and fatigue. All of these are local behaviours, and all are used as surrogates for actual structural failure. A structure is a system, comprised of elements, which in turn are built from materials.As an example, yielding can be considered. Yielding is a material level …failure‟, very common, usually very localized, and usually producing noobservable effect. It can be quite irrelevant. The important issue is the behaviour and failure of the structural system, even at the level of the structural components. Ship structures are especially redundant structures, quite unlike most civil structures and buildings. Ship structures are exposed to some of the harshest loading regimes, yet are usually capable of tolerating extensive material and component failure, prior to actual structural collapse.An essential deficiency of all traditional structural standards has been the failure to consider the structural redundancy (path to failure) and identify weaknesses in the system. Areas of weakness are normally defined as those parts that will first yield or fail.However, far more important is the ability of the structure to withstand these and subsequent local/material failures and redistribute the load. The real weaknesses are a lack of secondary load paths. It is often assumed, wrongly, that initial strength is a valid indicator for ultimate strength, and far simpler to assess. There is a need to focus on ways of creating robust structures, much as we use subdivision to create adequate damage stability. As another example, consider frames under lateral loads. When designed properly, frames can exhibit not only sufficient initial strength, but substantial reserve strength, due to the secondary load path created by axial stresses in the plate and frame. In effect, it is possible to create a ductile structure (analogous to a ductile material). If we instead use current designstandards that emphasize elastic section modulus, we risk creating a …brittle‟ structure, even w hen built from ductile materials.In the case of fatigue and buckling, it is again necessary to stand back from consideration of the initial effects, and examine whether there is sufficient reserve (secondary load paths). When there is no such reserve, there is the structural equivalent of a subdivision plan that cannot tolerate even one compartment flooding.The above discussion talks only about structural response, and indicated some gaps. Similar gaps exist in our knowledge of loads. The complexity of ship structures, the complexity of the loads that arise in a marine environment, and the dominating influence of human factors in any risk assessment for vessels, all present daunting challenges.The project team‟s approach to this project, described in the following sections, has intended to provide part of the basis for future design standard development.1.1集装箱运输的变化当商业已成为并将继续更加国际化，远洋集装箱运输已成为成倍增长的将任何种类的货物从一个港口移到另一个港口的手段。

船舶论文-外文翻译

1.1Container Shipping ChangesAs commerce has become and continues to be more international, ocean container shipments have grown exponentially as a means of moving most any kind of freight from one port to another. Buffered by waves of change touching other modes of transport, ocean carriers are in a constant process of altering the way they conduct their business to meet current needs of shipping customers. While chartered to serve a wider public with insight about the industry, the Container Shipping Information Service (CSIS) is able to provide a spokesperson from one of its 24 member companies to treat objectively with commonly shared issues. Andres Kulka, senior vice president of CSAV Group North America shares just such insights.In an environment of high transportation costs, ocean container shipping’s mix of speed, cost, availability and capability offers a superior value proposition, especially as logistics and supply chain management processes and systems are implemented by a growing range of shippers. Because of their shelf life or time value certain commodities must be transported by air. Increases in the need to speedily transport these commodities along with the greater economy will be a primary factor for airfreight growth in the future. But spiraling fuel surcharges and resulting cost consciousness among shippers opens opportunities for ocean carriers to gain market share in the broader spectrum of non- perishable commodities where airfreight’s cost effectiveness has diminished.Shortages of containers is produced by commercial imbalance situations. When exports outgrow imports in a geographic region, you may face equipment shortages, as was the case in Asia. When you add imbalance by type of equipment to the situation, the situation worsens. While at present leasing containers are available to meet the demand in Asia, container pricing has reached levels of $2,500 for a dry,due largely, to the increase of commodities costs and deterioration of the US exchangeThere have been reports of shortages of containers, particularly for cargo moving from Asia.Under these conditions,shipping lines are relying primarily on empty repositioning to Asia rather than use of fresh equipment.The shortage of equipment in the US today is due to two primary factors. First,exports are growing at high rates, mainly because of devaluation of the USdollar.Additionally imports are pretty much staggered causing, again, a commercial imbalance. Secondly, last year many nonprofitable international intermodal lanes were eliminated. This reduced the stock of containers at some inland locations available for exports.Location specific equipment shortages have created the need for increasing empty container repositioning. That is one of the reasons export freight rates have gone up. Media pays great attention to Asian business, but how healthy is container shipping in other regions, say Latin America?In fact trade with Latin America has been sensitive to the sharp fall of theUS dollar. For example in 2007 the Brazilian real was down 17% and the Chilean peso fell 7%. For exports total 2007 volumes for Latin America were about 800,000 TEU (twenty-foot equivalent units), approximately 20% greater than 2006. Top commodities exported to Latin America have been resins,chemicals, plastics, forest products and general merchandise. Higher rates have followed the increase in export demand.Foodstuffs and forest products dominate import volumes from South America, about 970,000 TEU in 2007. Unlike exports, import volume growth—5.5% greater than 2006—has slowed due to the decline of the US dollar. Import rates have risen, but not nearly as strongly as export rates. So far in 2008 the US dollar has continued its downward trend. We are very cautious about the future outlook. Even though exports will probably continue growing at high rates, imports might continue decreasing.1.2Discussion of Structural Standards DevelopmentTaken as a whole, there has been a piecemeal approach to structural design standards. As technical developments occur (models of various structural behaviours, risk methodologies), they have been incorporated into structural standards. Individuals and rule committees have framed their own rules with an emphasis on certain load/strength/failure models, coupled with some risk avoidance strategy (explicit or implicit). It is hardly surprising that various standards are different, even quite different. More,rather than fewer, concepts are available to those who develop structural standards. In the absence of a binding philosophy of structural behaviour, there will continue to be divergence along the way to improved standards. It must be appreciated that all current standards “work”. Any of the current naval and commercial ship design approaches can be used to produce structural designs that function with adequate reliability over a 20+ yearlife expectancy, unless subjected to poor maintenance, human operational error, or deliberate damage. Changes to standards are, therefore, resisted by all those who have invested time and effort in them as developers and users. The rationale for change must be presented well, and its benefits have to outweigh its costs.Experienced designers recognize that structural behaviour can be very complex. Despite this, it is necessary to use simple, practical approaches in design standards, to avoid adding to the problem through overly-complex rules that are difficult to apply and more so to check and audit. Stress is the primary load-effect that standards focus on, partly because it is so readily calculated. The main concerns are material yielding, buckling and fatigue. All of these are local behaviours, and all are used as surrogates for actual structural failure. A structure is a system, comprised of elements, which in turn are built from materials.As an example, yielding can be considered. Yielding is a material level‘failure’, very common, usually very localized, and usually producing noobservable effect. It can be quite irrelevant. The important issue is the behaviour and failure of the structural system, even at the level of the structural components. Ship structures are especially redundant structures, quite unlike most civil structures and buildings. Ship structures are exposed to some of the harshest loading regimes, yet are usually capable of tolerating extensive material and component failure, prior to actual structural collapse.An essential deficiency of all traditional structural standards has been the failure to consider the structural redundancy (path to failure) and identify weaknesses in the system. Areas of weakness are normally defined as those parts that will first yield or fail.However, far more important is the ability of the structure to withstand these and subsequent local/material failures and redistribute the load. The real weaknesses are a lack of secondary load paths. It is often assumed, wrongly, that initial strength is a valid indicator for ultimate strength, and far simpler to assess. There is a need to focus on ways of creating robust structures, much as we use subdivision to create adequate damage stability. As another example, consider frames under lateral loads. When designed properly, frames can exhibit not only sufficient initial strength, but substantial reserve strength, due to the secondary load path created by axial stresses in the plate and frame. In effect, it is possible to create a ductile structure (analogous to a ductile material). If we instead use current designstandards that emphasize elastic section modulus, we risk creating a‘brittle’ structure, even w hen built from ductile materials.In the case of fatigue and buckling, it is again necessary to stand back from consideration of the initial effects, and examine whether there is sufficient reserve (secondary load paths). When there is no such reserve, there is the structural equivalent of a subdivision plan that cannot tolerate even one compartment flooding.The above discussion talks only about structural response, and indicated some gaps. Similar gaps exist in our knowledge of loads. The complexity of ship structures, the complexity of the loads that arise in a marine environment, and the dominating influence of human factors in any risk assessment for vessels, all present daunting challenges.The project team’s approach to this project, described in the following sections, has intended to provide part of the basis for future design standard development.1.1集装箱运输的变化当商业已成为并将继续更加国际化，远洋集装箱运输已成为成倍增长的将任何种类的货物从一个港口移到另一个港口的手段。

船舶设计原理文献

船舶设计原理文献船舶设计原理是指在设计一艘船舶时所依据的原则和理论。

船舶设计原理涉及多个学科领域，如流体力学、结构力学、材料科学等，综合运用这些知识可以优化船舶的性能和安全性。

以下是一些关于船舶设计原理的文献，可以从不同角度对船舶设计原理进行研究和了解。

1. Papanikolaou, A., & Belenky, V. L. (2004). Principles of naval architecture: stability and strength. Society of Naval Architects & Marine.这本书是船舶设计原理中关于稳定性和强度方面的经典教材。

书中详细介绍了船舶在不同环境条件下的稳定性计算方法和结构强度设计原理，包括船舶的刚性和弹性理论等。

2. Carlton, J. (1994). Marine propellers and propulsion. Butterworth-Heinemann.这本书主要介绍了船舶推进系统的设计原理。

包括螺旋桨的几何形状、流体力学特性和推进效率等内容。

对于了解船舶的推进系统设计和优化具有重要的参考价值。

3. Rawson, K. J., & Tupper, E. C. (2001). Basic ship theory. Elsevier.这本书是船舶设计原理中的经典教材之一，内容涵盖了船舶力学、流体力学、船舶操纵等方面的原理。

其中包括船舶运动的数学模型、船舶操纵性能、船舶水动力性能等内容，是了解船舶设计原理的基本工具书。

4. Faltinsen, O. M. (2005). Hydrodynamics of high-speed marine vehicles. Cambridge University Press.这本书主要介绍了高速船舶的流体力学原理和设计方法，包括阻力和推进性能的计算、船体波浪对船舶运动的影响等内容。

船舶设计外文文献翻译

外文文献翻译(译成中文1000字左右)：【主要阅读文献不少于5篇，译文后附注文献信息，包括:作者、书名(或论文题目）、出版社(或刊物名称)、出版时间(或刊号）、页码.提供所译外文资料附件（印刷类含封面、封底、目录、翻译部分的复印件等，网站类的请附网址及原文】Ships Typed According to Means of Physical SupportThe mode of physical support by which vessels can be categorized assumes that the vessel is operating under designed conditions。

Ships are designed to operate above, on, or below the surface of the sea，so the air-sea interface will be used as the reference datum. Because the nature of the physical environment is quite different for the three regions just mentioned, the physical characteristics of ships designed to operate in those regions can be diverse.Aerostatic SupportThere are two categories of vessels that are supported above the surface of the sea on a self-induced cushion of air. These relatively lightweight vehicles are capable of high speeds，since air resistance is considerably less than water resistance, and the absence of contact with small waves combined with flexible seals reduces the effects of wave impact at high speed。

船舶与海洋工程论文中英文资料外文翻译文献

中英文资料外文翻译文献A Simple Prediction Formula of Roll Damping of Conventional Cargo Ships on the Basis of lkeda's Method and Its LimitationSince the roll damping of ships has significant effects of viscosity, it is difficult to calculate it theoretically. Therefore, experimental results or some prediction methods are used to get the roll damping in design stage of ships. Among some prediction methods, Ikeda’s one is widely used in many ship motion computer programs. Using the method, the roll damping of various ship hulls with various bilge keels can be calculated to investigate its characteristics. To calculate the roil damping of each ship, detailed data of the ship are needed to input. Therefore, a simpler prediction method is expected in primary design stage. Such a simple method must be useful to validate the results obtained by a computer code to predict it on the basis of Ikeda，s method, too. On the basis of the predicted roll damping by Ikeda’s method for various ships, a very simple prediction formula of the roll damping of ships is deduced in the present paper. Ship hull forms are systematically changed by changing length, beam, draft, mid-ship sectional coefficient and prismatic coefficient. It is found, however, that this simple formula can not be used for ships that have high position of the center of gravity. A modified method to improve accuracy for such ships is proposed.Key words: Roll damping, simple prediction formula, wave component, eddy component, bilge keel component.IntroductionIn 1970s, strip methods for predicting ship motions in 5-degree of freedoms in waves have been established. The methods are based on potential flow theories (Ursell-Tasai method, source distribution method and so on), and can predict pitch, heave, sway and yaw motions of ships in waves in fairly good accuracy. In roll motion, however, the strip methods do not work well because of significant viscous effects on the roll damping. Therefore, some empirical formulas or experimental dataare used to predict the roll damping in the strip methods.To improve the prediction of roll motions by these strip methods, one of the authors carried out a research project to develop a roll damping prediction method which has the same concept and the same order of accuracy as the strip methods which are based on hydrodynamic forces acting on strips. The review of the prediction method was made by Himeno [5] and Ikeda [6，7] with the computer program.The prediction method, which is now called Ikeda’s method, divides the roll damping into the frictional (BF), the wave (Bw)，the eddy (Be) and the bilge keel (Bbk) components at zero forward speed, and at forward speed, the lift (Bi) is added. Increases of wave and friction components due to advance speed are also corrected on the basis of experimental results. Then the roll damping coefficient B44 (= roll damping moment (kgfm)/roll angular velocity (rad/sec)) can be expressed as follows: B44 B bk (1)At zero forward speed, each component except the friction and lift components are predicted for each cross section with unit length and the predicted values are summed up along the ship length. The friction component is predicted by Kato’s formula for a three-dimensional ship shape. Modification functions for predicting the forward speed effects on the roll damping components are developed for the friction, wave and eddy components. The computer program of the method was published, and the method has been widely used.For these 30 years, the original Ikeda’s method developed for conven tional cargo ships has been improved to apply many kinds of ships, for examples, more slender and round ships, fishing boats, barges, ships with skegs and so on. The original method is also widely used. However, sometimes, different conclusions of roll mot ions were derived even though the same Ikeda’s method was used in the calculations. Then, to check the accuracy of the computer programs of the same Ikeda’s method, a more simple prediction method with the almost same accuracy as the Ikeda’s original one h as been expected to be developed. It is said that in design stages of ships, Ikeda’s method is too complicated to use. To meet these needs, a simple roll damping prediction method was deduced by using regression analysis [8].Previous Prediction FormulaThe simple prediction formula proposed in previous paper can not be used for modem ships that have high position of center of gravity or long natural roll period such as large passenger ships with relatively flat hull shape. In order to investigate its limitation, the authors compared the result of this prediction method with original Ikeda’s one while out of its calculating limitation. Fig. 1 shows the result of the comparison with their method of roll damping. The upper one is on the condition that the center of gravity is low and the lower one on the condition that the center of gravity is high.From this figure, the roll damping estimated by this prediction formula is in good agreement with the roll damping calculated by the Ikeda’s method for low positi on of center of gravity, but the error margin grows for the high position of center of gravity. The results suggest that the previous prediction formula is necessary to be revised. Methodical Series ShipsModified prediction formula will be developed on the basis of the predicted results by Ikeda’s method using the methodical series ships. This series ships are constructed based on the Taylor Standard Series and its hull shapes are methodically changed by changing length, beam, draft, midship sectional coefficient and longitudinal prismatic coefficient. The geometries of the series ships are given by the following equations. Proposal of New Prediction Method of Roll DampingIn this chapter, the characteristics of each component of the roll damping, the frictional, the wave, the eddy and the bilge keel components at zero advanced speed, are discussed, and a simple prediction formula of each component is developed.As well known, the wave component of the roll damping for a two-dimensional cross section can be calculated by potential flow theories in fairly good accuracy. In Ikeda's method, the wave damping of a strip section is not calculated and the calculated values by any potential flow theories are used as the wave damping.reason why viscous effects are significant in only roll damping can be explained as follows. Fig. 4 shows the wave component of the roll damping for 2-D sections calculated by a potential flow theory.ConclusionsA simple prediction method of the roll damping of ships is developed on the basis of the Ikeda’s original prediction method which was developed in the same concept as a strip method for calculating ship motions in waves. Using the data of a ship, B/d, Cb，Cm, OG/d, G)，bBK/B, Ibk/Lpp，(pa, the roll damping of a ship can be approx imately predicted. Moreover, the limit of application of Ikeda’s prediction method to modern ships that have buttock flow stern is demonstrated by the model experiment. The computer program of the method can be downloaded from the Home Page of Ikeda’s Labo (AcknowledgmentsThis work was supported by the Grant-in Aid for Scientific Research of the Japan Society for Promotion of Science (No. 18360415).The authors wish to express sincere appreciation to Prof. N. Umeda of Osaka University for valuable suggestions to this study.References五、Y. Ikeda, Y. Himeno, N. Tanaka, On roll damping force of shipEffects of friction of hull and normal force of bilge keels, Journal of the Kansai Society of Naval Architects 161 (1976) 41-49. (in Japanese)六、Y. Ikeda, K. Komatsu, Y. Himeno, N. Tanaka, On roll damping force of ship~Effects of hull surface pressure created by bilge keels, Journal of the Kansai Society of Naval Architects 165 (1977) 31-40. (in Japanese)七、Y. Ikeda, Y. Himeno, N. Tanaka, On eddy making component of roll damping force on naked hull, Journal of the Society of Naval Architects 142 (1977) 59-69. (in Japanese)八、Y. Ikeda, Y. Himeno, N. Tanaka, Components of roll damping of ship at forward speed, Journal of the Society of Naval Architects 143 (1978) 121-133. (in Japanese) 九、Y. Himeno, Prediction of Ship Roll Damping一State of the Art, Report of Department of Naval Architecture & Marine Engineering, University of Michigan, No.239, 1981.十、Y. Ikeda, Prediction Method of Roll Damping, Report of Department of Naval Architecture, University of Osaka Prefecture, 1982.十一、Y. Ikeda, Roll damping, in: Proceedings of 1stSymposium of Marine Dynamics Research Group, Japan, 1984, pp. 241-250. (in Japanese)十二、Y. Kawahara, Characteristics of roll damping of various ship types and as imple prediction formula of roll damping on the basis of Ikeda’s method, in: Proceedings of the 4th Asia-Pacific Workshop on Marine Hydrodymics, Taipei, China, 2008，pp. 79-86.十三、Y. Ikeda, T. Fujiwara, Y. Himeno, N. Tanaka, Velocity field around ship hull in roll motion, Journal of the Kansai Society of Naval Architects 171 (1978) 33-45. (in Japanese)十四、N. Tanaka, Y. Himeno, Y. Ikeda, K. Isomura,Experimental study on bilge keel effect for shallow draftship, Journal of the Kansai Society of Naval Architects 180 (1981) 69-75. (in Japanese)常规货船的横摇阻尼在池田方法基础上的一个简单预测方法及其局限性摘要：由于船的横摇阻尼对其粘度有显着的影响，所以很难在理论上计算。

船舶与海洋工程论文中英文资料外文翻译文献

船舶专业外文文献

The spatial scheduling problem is to schedule a set of jobs, of which each requires its physical space in a restricted space. This problem is complicated because both the scheduling of assemblies with different due dates and earliest starting times and the spatial allocation of blocks with different sizes and loads must be considered simultaneously。

船舶专业外文文献

Spatial scheduling for large assembly blocks inshipbuildingAbstract: This paper addresses the spatial scheduling problem (SPP) for large assembly blocks, which arises in a shipyard assembly shop. The spatial scheduling problem is to schedule a set of jobs, of which each requires its physical space in a restricted space. This problem is complicated because both the scheduling of assemblies with different due dates and earliest starting times and the spatial allocation of blocks with different sizes and loads must be considered simultaneously. This problem under consideration aims to the minimization of both the makespan and the load balance and includes various real-world constraints, which includes the possible directional rotation of blocks, the existence of symmetric blocks, and the assignment of some blocks to designated workplaces or work teams. The problem is formulated as a mixed integer programming (MIP) model and solved by a commercially available solver. A two-stage heuristic algorithm has been developed to use dispatching priority rules and a diagonal fill space allocation method, which is a modification ofbottom-left-fill space allocation method. The comparison and computational results shows the proposed MIP model accommodates various constraints and the proposed heuristic algorithm solves the spatial scheduling problems effectively and efficiently.Keywords: Large assembly block; Spatial scheduling; Load balancing; Makespan; Shipbuilding1. IntroductionShipbuilding is a complex production process characterized by heavy and large parts, various equipment, skilled professionals, prolonged lead time, and heterogeneous resource requirements. The shipbuilding process is divided into sub processes in the shipyard, including ship design, cutting and bending operations, block assembly, outfitting, painting, pre-erection and erection. The assembly blocks are called the minor assembly block, the sub assembly block, and the large assembly block according to their size and progresses in the course of assembly processes. This paper focuses on the spatial scheduling problem of large assembly blocks in assembly shops. Fig. 1 shows a snapshot of large assembly blocks in a shipyard assembly shop.Recently, the researchers and practitioners at academia and shipbuilding industries recently got together at “Smart Production Technology Forum in Shipbuilding and Ocean Plant Industries” to recognize that there are various spatial scheduling problems in every aspect of shipbuilding due to the limited space, facilities, equipment, labor and time. The SPPs occur in various working areas such as cutting and blast shops, assembly shops, outfitting shops, pre-erection yard, and dry docks. The SPP at different areas has different requirements and constraints to characterize the unique SPPs. In addition, the depletion of energy resources on land put more emphasis on the ocean development. The shipbuilding industries face the transition of focus from the traditional shipbuilding to ocean plant manufacturing. Therefore, the diversity of assembly blocks, materials, facilities and operations in ship yards increases rapidly.There are some solution providers such as Siemens™ and Dassult Systems™ to provide integrated software including product life management, enterprise resource planning system, simulation and etc. They indicated the needs of efficient algorithms to solve medium- to large-sized SPP problems in 20min, so that the shop can quickly re-optimize the production plan upon the frequent and unexpected changes in shop floors with the ongoing operations on exiting blocks intact.There are many different applications which require efficient scheduling algorithms with various constraints and characteristics (Kim and Moon, 2003, Kim et al., 2013, Nguyen and Yun, 2014and Yan et al., 2014). However, the spatial scheduling problem which considers spatial layout and dynamic job scheduling has not been studied extensively. Until now, spatial scheduling has to be carried out by human schedulers only with their experiences and historical data. Even when human experts have much experience in spatial scheduling, it takes a long time and intensive effort to produce a satisfactory schedule, due to the complexity of considering blocks’ geometric shapes, loads, required facilities, etc. In practice, spatial scheduling for more than asix-month period is beyond the human schedulers’ capacity. Moreover, the space in the working areas tends to be the most critical resource in shipbuilding. Therefore, the effective management of spatial resources through automation of the spatial scheduling process is a critical issue in the improvement of productivity in shipbuilding plants.A shipyard assembly shop is consisted of pinned workplaces, equipment, and overhang cranes. Due to the heavy weight of large assembly block, overhang cranes are used to access any areas over other objects without any hindrance in the assembly shop. The height of cranes can limit the height of blocks that can be assembled in the shop. The shop can be considered as a two-dimensional space. The blocks are placed on precisely pinned workplaces.Once the block is allocated to a certain area in a workplace, it is desirable not to move the block again to different locations due to the size and weight of the large assembly blocks. Therefore, it is important to allocate the workspace to each block carefully, so that the workspace in an assembly shop can be utilized in a most efficient way. In addition, since each block has its due date which is pre-determined at the stage of ship design, the tardiness of a block assembly can lead to severe delay in the following operations. Therefore, in the spatial scheduling problem for large assembly blocks, the scheduling of assembly processes for blocks and the allocation of blocks to specific locations in workplaces must be considered at the same time. As the terminology suggests, spatial scheduling pursues the optimal spatial layout and the dynamic schedule which can also satisfy traditional scheduling constraints simultaneously. In addition, there are many constraints or requirements which are serious concerns on shop floors and these complicate the SPP. The constraints or requirements this study considered are explained here: (1) Blocks can be put in either directions, horizontal or vertical. (2) Since the ship is symmetric around the centerline, there exist symmetric blocks. These symmetric blocks are required to be put next to each other on the same workplace. (3) Some blocks are required to be put on a certain special area of the workplace, because the work teams on that area has special equipment or skills to achieve a certain level of quality or complete the necessary tasks. (4) Frequently, the production plan may not be implemented as planned, so that frequent modifications in production plans are required to cope with the changes in the shop. At these modifications, it is required to produce a new modified production plan which does not remove or move the pre-existing blocks in the workplace to complete the ongoing operations.(5) If possible at any time, the load balancing over the work teams, i.e., workplaces are desirable in order tokeep all task assignments to work teams fair and uniform.Lee, Lee, and Choi (1996) studied a spatial scheduling that considers not only traditional scheduling constraints like resource capacity and due dates, but also dynamic spatial layout of the objects. They usedtwo-dimensional arrangement algorithm developed by Lozano-Perez (1983) to determine the spatial layout of blocks in shipbuilding. Koh, Park, Choi, and Joo (1999) developed a block assembly scheduling system for a shipbuilding company. They proposed a two-phase approach that includes a scheduling phase and a spatial layout phase. Koh, Eom, and Jang (2008) extended their precious works (Koh et al., 1999) by proposing the largest contact area policy to select a better allocation of blocks. Cho, Chung, Park, Park, and Kim (2001) proposed a spatial scheduling system for block painting process in shipbuilding, including block scheduling, four arrangement algorithms and block assignment algorithm. Park et al. (2002) extended Cho et al. (2001) utilizing strategy simulation in two consecutive operations of blasting and painting. Shin, Kwon, and Ryu (2008) proposed a bottom-left-fill heuristic method for spatial planning of block assemblies and suggested a placement algorithm for blocks by differential evolution arrangement algorithm. Liu, Chua, and Wee (2011) proposed a simulation model which enabled multiple priority rules to be compared. Zheng, Jiang, and Chen (2012) proposed a mathematical programming model for spatial scheduling and used several heuristic spatial scheduling strategies (grid searching and genetic algorithm). Zhang and Chen (2012) proposed another mathematical programming model and proposed the agglomeration algorithm.This study presents a novel mixed integer programming (MIP) formulation to consider block rotations, symmetrical blocks, pre-existing blocks, load balancing and allocation of certain blocks to pre-determined workspace. The proposed MIP models were implemented by commercially available software, LINGO® and problems of various sizes are tested. The computational results show that the MIP model is extremely difficult to solve as the size of problems grows. To efficiently solve the problem, a two-stage heuristic algorithm has been proposed.Section 2 describes spatial scheduling problems and assumptions which are used in this study. Section 3 presents a mixed integer programming formulation. In Section 4, a two-stage heuristic algorithm has been proposed, including block dispatching priority rules and a diagonal fill space allocation heuristic method, which is modified from the bottom-left-fill space allocation method. Computational results are provided in Section 5. The conclusions are given in Section 6.2. Problem descriptionsThe ship design decides how to divide the ship into many smaller pieces. The metal sheets are cut, blast, bend and weld to build small blocks. These small blocks are assembled to bigger assembly blocks. During this shipbuilding process, all blocks have their earliest starting times which are determined from the previous operational step and due dates which are required by the next operational step. At each step, the blocks have their own shapes of various sizes and handling requirements. During the assembly, no block can overlap physically with others or overhang the boundary of workplace.The spatial scheduling problem can be defined as a problem to determine the optimal schedule of a given set of blocks and the layout of workplaces by designating the blocks’ workplace simultaneously. As the term implies, spatial scheduling pursues the optimal dynamic spatial layout schedule which can also satisfy traditional scheduling constraints. Dynamic spatial layout schedule can be including the spatial allocation issue, temporal allocation issue and resource allocation issue.An example of spatial scheduling is given in Fig. 2. There are 4 blocks to be allocated and scheduled in a rectangular workplace. Each block is shaded in different patterns. Fig. 2 shows the 6-day spatial schedule of four large blocks on a given workplace. Blocks 1 and 2 are pre-existed or allocated at day 1. The earliest starting times of blocks 3 and 4 are days 2 and 4, respectively. The processing times of blocks 1, 2 and 3 are 4, 2 and 4days, respectively.The spatial schedule must satisfy the time and space constraints at the same time. There are many objectives in spatial scheduling, including the minimization of makespan, the minimum tardiness, the maximum utilization of spatial and non-spatial resources and etc. The objective in this study is to minimize the makespan and balance the workload over the workspaces.There are many constraints for spatial scheduling problems in shipbuilding, depending on the types of ships built, the operational strategies of the shop, organizational restrictions and etc. Some basic constraints are given as follows; (1) all blocks must be allocated on given workplaces for assembly processes and must not overstep the boundary of the workplace; (2) any block cannot overlap with other blocks; (3) all blocks have their own earliest starting time and due dates; (4) symmetrical blocks needs to be placed side-by-side in the same workspace. Fig. 3 shows how symmetrical blocks need to be assigned; (5) some blocks need to be placed in the designated workspace; (6) there can be existing blocks before the planning horizon; (7) workloads for workplaces needs to be balanced as much as possible.In addition to the constraints described above, the following assumptions are made.(1) The shape of blocks and workplaces is rectangular.(2 )Once a block is placed in a workplace, it cannot be moved or removed from its location until the process is completed.(3 ) Blocks can be rotated at angles of 0° and 90° (see Fig. 4).(4) The symmetric blocks have the same sizes, are rotated at the same angle and should be placed side-by-side on the same workplace.(5) The non-spatial resources (such as personnel or equipment) are adequate.3. A mixed integer programming modelA MIP model is formulated and given in this section. The objective function is to minimize makespan and the sum of deviation from average workload per workplace, considering the block rotation, the symmetrical blocks, pre-existing blocks, load balancing and the allocation of certain blocks to pre-determined workspace.A workspace with the length LENW and the width WIDW is considered two-dimensional rectangular space. Since the rectangular shapes for the blocks have been assumed, a block can be placed on workspace by determining (x, y) coordinates, where 0⩽x⩽LENW and 0⩽y⩽WIDW. Hence, the dynamic layout of blocks on workplaces is similar to two-dimensional bin packing problem. In addition to the block allocation, the optimal schedule needs to be considered at the same time in spatial scheduling problems. Z axis is introduced to describe the time dimension. Then, spatial scheduling problem becomes a three-dimensional bin packing problem with various objectives and constraints.The decision variables of spatial scheduling problem are (x, y, z) coordinates of all blocks within athree-dimensional space whose sizes are LENW, WIDW and T in x, y and z axes, where T represents the planning horizon. This space is illustrated in Fig. 5.In Fig. 6, the spatial scheduling of two blocks into a workplace is illustrated as an example. The parameters p1 and p2 indicate the processing times for Blocks 1 and 2, respectively. As shown in z axis, Block 2 is scheduled after Block 1 is completed.4. A two-stage heuristic algorithmThe computational experiments for the MIP model in Section 3 have been conducted using a commercially available solver, LINGO®. Obtaining global optimum solutions is very time consuming, considering the number of variables and constraints. A ship is consisted of more than 8 hundred large blocks and the size of problem using MIP model is beyond today’s computational ability. A two-stage heuristic algorithm has been proposed using the dispatching priority rules and a diagonal fill method.4.1. Stage 1: Load balancing and sequencingPast research on spatial scheduling problems considers various priority rules. Lee et al. (1996) used a priority rule for the minimum slack time of blocks. Cho et al. (2001) and Park et al. (2002) used the earliest due date. Shin et al. (2008) considered three dispatching priority rules for start date, finish date and geometric characteristics (length, breadth, and area) of blocks. Liu and Teng (1999) compared 9 different dispatching priority rules including first-come first-serve, shortest processing time, least slack, earliest due date, critical ratio, most waiting time multiplied by tonnage, minimal area residue, and random job selection. Zheng et al. (2012) used a dispatching rule of longest processing time and earliest start time.Two priority rules are used in this study to divide all blocks into groups for load balancing and to sequence them considering the due date and earliest starting time. Two priority rules are streamlined to load-balance and sequence the blocks into an algorithm which is illustrated in Fig. 7. The first step of the algorithm in this stage is to group the blocks based on the urgency priority. The urgency priority is calculated by subtracting the earliest starting time and the processing time from the due date for each block. The smaller the urgency priority, the more urgent the block needs to bed scheduled. Then all blocks are grouped into an appropriate number of groups for a reasonable number of levels in urgency priorities. Let g be this discretionary number of groups. There are g groups of blocks based on the urgency of blocks. The number of blocks in each group does not need to be identical.Blocks in each group are re-ordered grouped into as many subgroups as workplaces, considering the workload of blocks such as the weight or welding length. The blocks in each subgroup have the similar urgency and workloads. Then, these blocks in each subgroup are ordered in an ascending order of the earliest starting time. This ordering will be used to block allocations in sequence. The subgroup corresponds to the workplace.If block i must be processed at workplace w and is currently allocated to other workplace or subgroup than w, block i is s with a block at the same position of block i in an ascending order of the earliest starting time at its workplace (or subgroup). Since the symmetric blocks must be located on a same workplace, a similar s method can be used. One of symmetric blocks which are allocated into different workplace (or subgroups) needs to be selected first. In this study, we selected one of symmetric blocks whichever has shown up earlier in an ascending order of the earliest starting time at their corresponding workplace (or subgroup). Then, theselected block is s with a block at the same position of symmetric blocks in an ascending order of the earliest starting time at its workplace (or subgroups).4.2. Stage 2: Spatial allocationOnce the blocks in a workplace (or subgroup) are sequentially ordered in different urgency priority groups, each block can be assigned to workplaces one by one, and allocated to a specific location on a workplace. There has been previous research on heuristic placement methods. The bottom-left (BL) placement method was proposed by Baker, Coffman, and Rivest (1980) and places rectangles sequentially in a bottom-left most position. Jakobs (1996) used a bottom-left method that is combined with a hybrid genetic algorithm (see Fig.8). Liu and Teng (1999) developed an extended bottom-left heuristic which gives priority to downward movement, where the rectangles is only slide leftwards if no downward movement is possible. Chazele (1983) proposed the bottom-left-fill (BLF) method, which searches for lowest bottom-left point, holes at the lowest bottom-left point and then place the rectangle sequentially in that bottom-left position. If the rectangle is not overlapped, the rectangle is placed and the point list is updated to indicate new placement positions. If the rectangle is overlapped, the next point in the point list is selected until the rectangle can be placed without any overlap. Hopper and Turton (2000) made a comparison between the BL and BLF methods. They concluded that the BLF method algorithm achieves better assignment patterns than the BL method for Hopper’s example problems.Spatial allocation in shipbuilding is different from two-dimensional packing problem. Blocks have irregular polygonal shapes in the spatial allocation and blocks continuously appear and disappear since they have their processing times. This frequent placement and removal of blocks makes BLF method less effective in spatial allocation of large assembly block.In order to solve these drawbacks, we have modified the BLF method appropriate to spatial scheduling for large assembly blocks. In a workplace, since the blocks are placed and removed continuously, it is more efficient to consider both the bottom-left and top-right points of placed blocks instead of bottom-left points only. We denote it as diagonal fill placement (see Fig. 9). Since the number of potential placement considerations increases, it takes a bit more time to implement diagonal fill but the computational results shows that it is negligible.The diagonal fill method shows better performances than the BLF method in spatial scheduling problems. When the BLF method is used in spatial allocation, the algorithm makes the allocation of some blocks delayed until the interference by pre-positioned blocks are removed. It generates a less effective and less efficient spatial schedule. The proposed diagonal fill placement method resolve this delays better by allocating the blocks as soon as possible in a greedy way, as shown in Fig. 10. The potential drawbacks from the greedy approaches is resolved by another placement strategy to minimize the possible dead spaces, which will be explained in the following paragraphs.The BLF method only focused on two-dimensional bin packing. Frequent removal and placement of blocks in a workspace may lead to accumulation of dead spaces, which are small and unusable spaces among blocks. A minimal possible-dead space strategy has been used along with the BLF method. Possible-dead spaces arebeing generated over the spatial scheduling and they have less chance to be allocated for future blocks. The minimal possible-dead space strategy minimizes the potential dead space after allocating the following blocks (Chung, 2001and Koh et al., 2008) by considering the 0° and 90° rotation of the block and allocating the following block for minimal possible-dead space. Fig. 11 shows an example of three possible-dead space calculations using the neighbor block search method. When a new scheduling block is considered to be allocated, the rectangular boundary of neighboring blocks and the scheduling blocks is searched. This boundary can be calculated by obtaining the smallest and the largest x and y coordinates of neighboring blocks and the scheduling blocks. Through this procedure, the possible-dead space can be calculated as shown in Fig. 11. Considering the rotation of the scheduling blocks and the placement consideration points from the diagonal fill placement methods, the scheduling blocks will be finally allocated.In this two-stage algorithm, blocks tend to be placed adjacent to one of the alternative edges and their assignments are done preferentially to minimize fractured spaces.5. Computational resultsTo demonstrate the effectiveness and efficiency of the proposed MIP formulation and heuristic algorithm, the actual data about 800+ large assembly blocks from one of major shipbuilding companies has been obtained and used. All test problems are generated from this real-world data.All computational experiments have been carried out on a personal computer with a Intel® Core™ i3-2100 CPU @ 3.10GHz with 2GB RAM. The MIP model in Section 3 has been programmed and solved using LINGO® version 10.0, a commercially available software which can solve linear and nonlinear models. The proposed two-stage heuristic algorithm has been programmed in JAVA programming language.Because our computational efforts to obtain the optimal solutions for even small problems are more than significant, the complexity of SPP can be recognized as one of most difficult and time consuming problems.Depending on the scaling factor α in objective function of the proposed MIP formulation, the performance of the MIP model varies significantly. Setting α less than 0.01 makes the load balancing capability to be ignored from the optimal solution in the MIP model. For computational experiments in this study, the results with the scaling factor set to 0.01 is shown and discussed. The value needs to be fine-turned to obtain the desirable outcomes.Table 1 shows a comparison of computational results and performance between the MIP models andtwo-stage heuristic algorithm. As shown in Table 1, the proposed two-stage heuristic algorithm finds thenear-optimal solutions for medium and large problems very quickly while the optimal MIP models was not able to solve the problems of medium or large sizes due to the memory shortage on computers. It is observed that the computational times for the MIP problems are rapidly growing as the problem sizes increases. The test problems in Table 1 have 2 workplaces.Table 1.Computational results and performance between the MIP models and two-stage heuristic algorithm.The MIP model Two-stage heuristic algorithmNumber of blocksOptimal solution Time (s)Best known solution Time (s)1012.3601014.00012.3600.0262022.380a38250.00021.3800.0783098.344a38255.00030.7400.21850––53.7600.719100––133.780 2.948200––328.86012.523300––416.06040.154400––532.36073.214Best feasible solution after 10h in Global Solver of LINGO®.Full-size tableTable optionsView in workspaceDownload as CSVThe optimal solutions for test problems with more than 50 blocks in Table 1 have been not obtained even after 24h. The best known feasible solutions after 10h for the test problems with 20 blocks and 30 blocks are reported in Table 1. It is observed that the LINGO® does not solve the nonlinear constraints very well as shown in Table 1. For very small problem with 10 blocks, the LINGO® was able to achieve the optimal solutions. For slightly bigger problems, the LINGO® took significantly more time to find feasible solutions. From this observation, the approaches to obtain the lower bound through the relaxation method and upper bounds are significant required in future research.In contrary, the proposed two-stage heuristic algorithm was able to find the good solutions very quickly. For the smallest test problem with 10 blocks, it was able to find the optimal solution as well. The computational times are 1014 and 0.026 s, respectively, for the MIP approach and the proposed algorithm. Interestingly, the proposed heuristic algorithm found significantly better solutions in only 0.078 and 0.218s, respectively, for the test problems with 20 and 30 blocks. For these two problems, the LINGO® generates the worse solutions than the heuristics after 10h of computational times. The symbol ‘–’ in Table 1 indicates that the Global Solver of LINGO® did not find the feasible solutions.Another observation on the two-stage heuristic algorithms is the robust computational times. Thecomputation times does not change much as the problem sizes increase. It is because the simple priority rules are used without considering many combinatorial configurations.Fig. 12 shows partial solutions of test problems with 20 and 30 blocks on 2 workplaces. The purpose of Fig. 12 is to show the progress of production planning generated by the two-stage heuristic algorithm. Two workplaces are in different sizes of (40, 30) and (35, 40), respectively.6. ConclusionsAs global warming is expected to open a new way to transport among continent through North Pole Sea and to expedite the oceans more aggressively, the needs for more ships and ocean plants are forthcoming. The shipbuilding industries currently face increased diversity of assembly blocks in limited production shipyard. Spatial scheduling for large assembly blocks holds the key role in successful operations of the shipbuilding companies.The task of spatial scheduling takes place at almost every stage of shipbuilding processes and the large assembly shop is one of the most congested operational areas in today’s shipbuilding. It is also known that the spatial scheduling problem has been the major source of the bottleneck. The practitioners in shipbuilding industries requires their production planning system to optimize the spatial scheduling and to respond quickly to the changes on the shop floor by re-optimizing the production plan in 20-min time frame. Most companies use a system employing heuristic methods in an ad-hoc manner without knowing how good their planning system is.To benchmark the performance of the heuristic algorithms, a novel MIP model has been proposed considering various real-world constraints that are raised by field professionals and engineers. Those include block rotations, symmetrical blocks, pre-existing blocks, load balancing and allocation of certain blocks topre-determined workspace. These constraints have not been considered simultaneously by previous researchers. The MIP formulation can be used as a target to evaluate their spatial scheduling system in shipbuilding companies.In addition, the expectation and need of major solution companies such as Siemens™ and Dassult Systems™ is an efficient and effective algorithm to perform spatial scheduling. When a new type of ships or ocean plants is designed and built, there is a higher chance to observe unexpected interruptions in production flows. These interruptions cause significant losses in time, labor, resource and etc. Therefore, the need to re-optimize spatial scheduling quickly in shorter amount of computational times becomes greater.The proposed two-stage heuristic algorithm uses a simple priority rules and dispatching rules to group the blocks for quick load balancing and suggests the diagonal fill placement method which is fit to spatial scheduling in shipbuilding. The computational results show that the proposed algorithm finds good solutions efficiently and effectively for test problems of all sizes. It also demonstrates that the computational times of the proposed algorithm are robust to problem sizes.In future, due to the incapability of the MIP solver to obtain the optimal solution efficiently, the relation of the proposed model is being performed to obtain the lower bound.。

1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。

外文文献翻译（译成中文1000字左右）：【主要阅读文献不少于5篇，译文后附注文献信息，包括：作者、书名（或论文题目）、出版社（或刊物名称）、出版时间（或刊号）、页码。

提供所译外文资料附件（印刷类含封面、封底、目录、翻译部分的复印件等，网站类的请附网址及原文】Ships Typed According to Means of Physical SupportThe mode of physical support by which vessels can be categorized assumes that the vessel is operating under designed conditions. Ships are designed to operate above, on, or below the surface of the sea, so the air-sea interface will be used as the reference datum. Because the nature of the physical environment is quite different for the three regions just mentioned, the physical characteristics of ships designed to operate in those regions can be diverse.Aerostatic SupportThere are two categories of vessels that are supported above the surface of the sea on a self-induced cushion of air. These relatively lightweight vehicles are capable of high speeds, since air resistance is considerably less than water resistance, and the absence of contact with small waves combined with flexible seals reduces the effects of wave impact at high speed. Such vessels depend on lift fans to create a cushion oflow-pressure air in an underbody chamber. This cushion of air must be sufficient to support the weight of the vehicle above the water surface.The first type of vessel has flexible “skirts” that entirely surround the air cushion and enable the ship to rise completely above the sea surface. This is called an air cushion vehicle (ACV), and in a limited sense it is amphibious.The other type of air-cushion craft has rigid side walls or thin hulls that extend below the surface of the water to reduce the amount of air flow required to maintain the cushion pressure. This type is called a captured-air-bubble vehicle (CAB). It requires less lift-fan power than an ACV, is more directionally stable, and can be propelled by water jets or supercavitating propellers. It is not amphibious, however, and has not yet achieved the popularity of the ACVs, which include passenger ferries, cross-channel automobile ferries, polar-exploration craft, landing craft, and riverine warface vessels. Hydrodynamic SupportThere are also two types of vessels that depend on dynamic support generated by relatively rapid forward motion of specially designed hydrodynamic shapes either on or beneath the surface of the water. A principle of physics states that any moving object that can produce an unsymmetrical flow pattern generates a lift force perpendicular to the direction of motion. Just as an airplane with (airfoil) produces lift when moving through the air, a hydrofoil, located beneath the surface and attached bymeans of a surface piercing strut, can dynamically support a vessel’s hull above the water.Planning hulls are hull forms characterized by relatively flat bottoms and shallowV-sections (especially forward of amidships) that produce partial to nearly full dynamic support for light displacement vessels and small craft at higher speeds. Planning craft are generally restricted in size and displacement because of the required power-to-weight ratio and the structural stresses associated with traveling at high speed in waves. Most planning craft are also restricted to operations in reasonably clam water, although some “deep V” hull forms are capable of operation in rough water.Hydrostatic SupportFinally, there is the oldest and most reliable type of support, hydrostatic support. All ships, boats, and primitive watercraft up to the twentieth century have depended upon the easily attained buoyant force of water for their operation.This hydrostatic support, commonly recognized as flotation, can be explained by a fundamental physical law that the ancient philosopher-mathematician Archimedes defined in the second century B.C. Archimedes’ Principle states that a body immersed in a liquid is buoyed up (or acted upon) by a force equal to the weight of the liquid displaced. This principle applies to all vessels that float (or submerge) in water---salt or fresh. And from this statement the name of the ships in the category are derived; they are generally called displacement hulls.Although this ship type is very familiar, its subcategories warrant special discussion. For example, in some vessels reasonably high speed must be combined with the ability to carry light cargo or to move more comfortably in rough water than a planning hull. High-speed planning-hull characteristics can be modified to produce a semidisplacement hull or semiplaning hull. These compromise craft, of course not as fast as full-planing hulls but faster than conventional displacement hull, must have more power and less weight than the latter. Such types are obviously the result of “tradeoffs.”The example cited above lies between clear-cut physically defined categories----it is not a good example of a variation of a true displacement-type ship. The latter must be recognized primarily as a displacement vessel, and its variations depend primarily on the distribution of buoyant volume----the extent of the depth and breadth of the hull below the water.The most ubiquitous type of displacement ship can be generally classified as the common carrier, a seagoing vessel. It may be employed for passenger service, light cargo-carrying, fishing by trawling or for hundreds of other tasks that do not require exceptional capacity, speed, submergence, or other special performance. It is the most common and easily recognizable type of ship, with moderate displacement, moderate speeds, moderate to large lengths, and moderate capacities. It usually embodies the maximum in cruising range and seaworthiness. It is the “ship for all seasons.” It is the standard to which all other ship classifications in the displacement category may be referred.The closest relative to this standard vessel, which plays a crucial role not only in world commerce but in the survival of the industrial world as well, is the bulk, oil carrier, the tanker, or supertanker. These terminologies are common but unspecific, and in this discussion they are inadequate, for what was called a supertanker several years ago is today not a supertanker. The industry itself has created a far more explicit nomenclature. Based upon the index of 1000000 tons oil cargo capacity, the size categories are LCC (large crude carrier), VLCC (very large crude carrier), and ULCC (ultra large crude carrier). Any tanker greater than 100000 tons but less than 200000 is a LCC, those between 200000 and 400000 are VLCCs, and those over 400000 are ULCCs. The current necessity for these designations becomes clear when we realize that before 1956 there were no tankers larger than 50000 tons, and not until the early sixties were any ships built larger than 100000 tons. In 1968 the first ship over 300000 tons was built. With their bulk and enormous capacity (four football fields can be placed end to end on one of their decks), these ships are designed and built to be profit-makers, enormously long, wide, and deep, carrying thousands of tons of crude oil per voyage at the least cost. Few of these elephantine tankers have more than one propeller shaft of rudder. Their navigation bridges are nearly one quarter of a mile from their bows. Their top service speed is so low that a voyage from an Arabian oil port to a European destination normally takes two months.Such vessels belong to a category of displacement ship that has a great range of buoyant support. They have a very large and disproportionate hull volume below the surface when fully loaded. Indeed, the cargo weight far exceeds the weight of the ship itself. The draft or depth of water required for a fully loaded VLCC runs to 50 or 60 feet and the ULCC may be 80 feet. Such ships belong in the exclusive category of displacement vessels called deep displacement ships.There exists another type of displacement hull with extreme draft. However, it is similarity to the crude-oil carrier of the preceding discussion goes no further than that. This type of vessel is called the SWATH( small waterplane area twin hull). Briefly, this rather rare breed of ship is designed for relatively high speed and stable platform in moderately rough water. Its future is problematical, but the theory of placing the bulk of the displacement well below the surface and extending the support to the above-water platform or deck through the narrow waterline fins or struts is sound. Twin hulls connected by an upper platform provide the necessary operating stability. The most significant class of displacement hull for special application is the sub marine, a vessel for completely submerged operation. The nature of the submarine and a description of her various operational attitudes, both static and dynamic, is covered in subsequent chapters. It is only necessary here to emphasize that submerisible vessels are specifically displacement vessels applying the theory of Archimedes’ Principle and all that it implies.Multihull VesselsThere is one other type of hull in common use that has not yet been mentioned, primarily because it fits into none of the categories described but rather can exist comfortably in any. This craft is the so-called multihull vessel----the catamaran andthe trimaran. These vessels are most frequently displacement hulls in their larger sizes, such as the SWATH mentioned above, or more conventionally, ocean research vessels requiring stable platforms and protected areas for launching equipment. There are also the twin-hulled CAB vessels mentioned earlier and high-speed planning catamarans. Actually, the multihull ship is an adaptation of any of the basic hull categories to a special application that requires exceptional transverse stability and/ or the interhull working area.中文翻译：按照物理支撑方式而划分的船舶类型就船舶分类而言，物理支撑形式是基本于船舶在设计情况下进行的假定。

船舶设计外文文献翻译

船舶专业外文翻译--船舶设计优化

船舶设计英文翻译

（完整版）船舶专业英语（课文+翻译）

船舶设计论文中英文外文翻译文献

船舶专业外文文献

(完整版)船舶专业英语(课文+翻译)

船舶专业英语(课文+翻译)

船舶设计外文翻译---船舶最大下沉量

船舶设计论文中英文外文翻译文献

船舶论文 外文翻译

船舶论文-外文翻译

船舶设计原理文献

船舶设计外文文献翻译

船舶与海洋工程论文中英文资料外文翻译文献

船舶与海洋工程论文中英文资料外文翻译文献

船舶专业外文文献

船舶专业外文文献

船舶论文外文翻译