2019精品建模实例英语
2019美赛建模A题
2019MCMProblem A:A Hot YoubotBackground:Thermal Analysis,using finite element techniques,is carried out as a steady-state or transient analysis.Conductive heat transfer is handled directly by finite element techniques; conduction occurs in a solid due to temperature differences.However,radiation heat transfer analysis may require additional particle-tracking or ray-tracing techniques to approximate the radiant energy arriving at a given surface.The material is assumed to be a magnesium alloy and to have a thermal conductivity of52W/m∙K. Material properties were taken from"Thermal Conductivity of Magnesium Alloys".Since the model is in inches you can use symunit to rewrite the value in inches.Now you need remove the units to obtain the value for the thermal properties.Unless overwritten,all of the side faces are set to have a natural convection coefficient of25W/m2∙K representing heat transfer to an ambient air temperature of288.15K(25℃).Convert and calculate the convection coefficient to W/inch2∙K to be consistent with the model dimensions.Explore different material selections for the robotic pute the change in max body temperature as a function of increasing thermal conductivity.Before begining calculate the expected run time from the previous run time.Run the models using a parfor loop to speed up the simulation by parallelizing the iterations across Parallel Computing Toolbox workers.If you do not have the Parallel Toolbox change parfor to for.Problem:Part I:Develop a mathematical model for the heat transfer among the gripper pivot.In the youBot,the gripper pivot sits underneath the electronics board and is exposed to the heat coming off the circut board.Here you will create the pde model,import the STL file of the gripper pivot, and plot it.Create and visualize a tetrahedral mesh of the component with a maximum value of 0.09inches.Measure the x,y and z dimensions of the mesh.Part II:The bottom face is given a fixed temperature assuming that the rest of the robotic arm acts as a heat sink.The top face and inner hole is arbitrarily given a heat flux to represent the heat off the circuit board.Solve the model and calculate the max and bulk body temperatures and time how long the solve pute the max temperature in K and rewrite that to℃and F,then plot the distribution of temperature of the gripper pivot in3D.Part III:Develop a mathematical model for predicting the relationship between thermal conductivity and max temperature for this geometry and material.Assume the robotic arm shuts off at a max temperature of311K,find the associated allowable heat transfer coefficient for the alloy.Which materials are appropriate for being made into the the gripper pivot?Part IV:Prepare a short(1to2pages)synopsis of your results suitable for publication as a short note in IEEE Communications Magazine.Your submission should consist of:●One-page Summary Sheet,●Two-page synopsis,●Your solution of no more than20pages,for a maximum of23pages with your summaryand synopsis.●Note:Reference list and any appendices do not count toward the23-page limit andshould appear after your completed solution.Reference:Lee,Sanghyun,et al."Thermal Conductivity of Magnesium Alloys in the Temperature Range from-125℃to400℃."International Journal of Thermophysics34.12(2013):2343-2350. Appendix:The structure of Gripper Pivot in youBot plotted by AutoCAD:ProblemAData：youBot.stl。
EA(EvermotionArchinteriors)(高品质完整室内场景模型)目录
【室内元素模型库共8DVD】DVD-1新编_Evermotion Archmodels_01（EA01-19）Evermotion Archmodels Vol 01 极品精细(各种现代沙发、椅子、床、桌子、睡椅等)Evermotion Archmodels Vol 02 极品精细家居模型(各种小电器、花瓶、蜡烛台等小摆设)Evermotion Archmodels Vol 03 极品精细家居模型(各种灯具)Evermotion Archmodels Vol 04 极品精细家居模型(各种房门、门把手、门锁等)Evermotion Archmodels Vol 05 极品精细家居模型(睡椅、老板椅等中大型椅)Evermotion Archmodels Vol 06 极品精细家居模型(卫浴专辑—各种浴缸、洗手盆、马桶等)Evermotion Archmodels Vol 07 极品精细家居模型(各种音响、平板电视、DVD，笔记本电脑、电脑系列（液晶、鼠标键盘等）等家用电器)Evermotion Archmodels Vol 08 极品精细家居模型(办公家具专辑—各种办公桌椅、档案柜等)Evermotion Archmodels Vol 09 极品精细家居模型(各种家用、办公柜子)Evermotion Archmodels Vol 10 极品精细家居模型(各种厨房电器—油烟机、冰箱、烤箱等)Evermotion Archmodels Vol 11 极品精细家居模型(各种床)Evermotion Archmodels Vol 12 极品精细家居模型(各种射灯，装饰灯)Evermotion Archmodels Vol 13 极品精细家居模型(广告牌、街灯、消防栓、站台等街头素材)Evermotion Archmodels Vol 14 极品精细家居模型(壁灯、草地灯)Evermotion Archmodels Vol 15 极品精细家居模型(洗浴间—面盆、浴缸、喷淋等)Evermotion Archmodels Vol 16 极品精细家居模型(家用沙发及办公桌椅)Evermotion Archmodels Vol 17 极品精细家居模型(现代化别墅景观)Evermotion Archmodels Vol 18 极品精细家居模型(餐具用品)Evermotion Archmodels Vol 19 极品精细家居模型(厨具及餐桌摆设)下载地址新编_Evermotion Archmodels_02（EA20-29）Evermotion Archmodels Vol 20 极品精细家居模型(办公室用小件)Evermotion Archmodels Vol 21 极品精细家居模型(时尚餐桌、会议桌、沙发、茶几、休闲椅子)Evermotion Archmodels Vol 22 极品精细家居模型(庭院系列—躺椅、烧烤炉、除草机、秋千、草地灯等)Evermotion Archmodels Vol 23 高质量家居装饰3D模型(厨房电器—洗衣机、冰箱、微波炉、灶台、烤箱、咖啡机、水壶、烤面包机等)Evermotion Archmodels Vol 24 极品精细家居模型(盆栽和室内植物)Evermotion Archmodels Vol 25 极品精细家居模型(家用多功能沙发)Evermotion Archmodels Vol 26 极品精细家居模型(时尚沙发、座椅)Evermotion Archmodels Vol 27 极品精细建筑3D模型装饰家居模型(健身房)Evermotion Archmodels Vol 28 极品精细建筑3D模型装饰家居模型(装饰灯)Evermotion Archmodels Vol 29 极品精细建筑3D模型装饰家居模型(豪华组合沙发)DVD-3 新编_Evermotion Archmodels_03（EA30-38）Evermotion Archmodels Vol 30 极品精细家居模型(织物)Evermotion Archmodels Vol 31 极品精细家居模型(植物)Evermotion Archmodels Vol 32 极品精细家居模型(摆设)Evermotion Archmodels Vol 33 极品精细家居模型(欧式豪华家具)Evermotion Archmodels Vol 34 极品精细家居模型(庭院雕塑)Evermotion Archmodels Vol 35 极品精细家居模型(电脑显示器功放)Evermotion Archmodels Vol 36 极品精细家居模型(床)Evermotion Archmodels Vol 37 极品精细家居模型(床)Evermotion Archmodels Vol 38 极品精细家居模型(现代灯具)DVD-4 新编_Evermotion Archmodels_04（EA39-46）Evermotion Archmodels Vol 39 极品精细家居模型(各种柜子)Evermotion Archmodels Vol 40 极品精细家居模型(家居小品)Evermotion Archmodels Vol 41 极品精细家居模型(室内植物)Evermotion Archmodels Vol 42 极品高质量植物模型(室内植物)Evermotion Archmodels Vol 43 极品精细家居模型(椅子)Evermotion Archmodels Vol 44 极品精细家居模型(商品货架)Evermotion Archmodels Vol 45 极品精细家居模型(现代家具)Evermotion Archmodels Vol 46 极品精细家居模型(卫浴设备)下载地址新编_Evermotion Archmodels_05（EA47-54）Evermotion Archmodels Vol 47 极品精细家居模型(体育设备)Evermotion Archmodels Vol 48 极品精细家居模型(帆船游艇)Evermotion Archmodels Vol 49 极品精细家居模型(眼镜皮包鞋子等)Evermotion Archmodels Vol 50 3D精品建筑装饰模型Evermotion Archmodels Vol 51 厨房用品库Evermotion Archmodels Vol 52 精品室内植物合集3D模型Evermotion Archmodels Vol 53 精品办公家具合集3D模型Evermotion Archmodels Vol 54 现代餐厅和家具模型DVD-6 新编_Evermotion Archmodels_06（EA55-58）Evermotion Archmodels Vol 55 交通工具合集Evermotion Archmodels Vol 56 浴室家具模型Evermotion Archmodels Vol 57 现代餐厅家具模型Evermotion Archmodels Vol 58 3D植物树模型DVD-7 新编_Evermotion Archmodels_07（EA59-60）Evermotion Archmodels Vol 59 现代家具模型.rarEvermotion Archmodels Vol 60 时尚窗帘模型.rarDVD-8 新编_Evermotion Archmodels_08（EA61）Evermotion Archmodels Vol 61 树木植物模型下载地址【室内场景模型库共3DVD】DVD-1 新编_EA_室内_01Evermotion Archinteriors vol 01 (高品质完整室内场景模型)Evermotion Archinteriors vol 02 (高品质完整室内场景模型)Evermotion Archinteriors vol 03 (高品质完整室内场景模型)Evermotion Archinteriors vol 04 (高品质完整室内场景模型)Evermotion Archinteriors vol 05 (高品质完整室内场景模型)Evermotion Archinteriors vol 06 (高品质完整室内场景模型)Evermotion Archinteriors vol 07 (高品质完整室内场景模型)Evermotion Archinteriors vol 08 (高品质完整室内场景模型)DVD-2 新编_EA_室内_02Evermotion Archinteriors vol 09 (高品质完整室内场景模型)Evermotion Archinteriors vol 10 (高品质完整室内场景模型)Evermotion Archinteriors vol 11 (高品质完整室内场景模型)Evermotion Archinteriors vol 12 (高品质完整室内场景模型)Evermotion Archinteriors vol 13 (高品质完整室内场景模型)DVD-3 新编_EA_室内_03Evermotion Archinteriors vol 14 (高品质完整室内场景模型)Evermotion Archinteriors vol 15 (高品质完整室内场景模型)【室外模型库共7DVD】DVD-1 新编_EA_室外_01Evermotion Archexteriors vol 01 (高品质完整室外场景模型)Evermotion Archexteriors vol 02 (高品质完整室外场景模型)Evermotion Archexteriors vol 03 (高品质完整室外场景模型)DVD-2 新编_EA_室外_02Evermotion Archexteriors vol 04 (高品质完整室外场景模型)Evermotion Archexteriors vol 05 (高品质完整室外场景模型)DVD-3 新编_EA_室外_03Evermotion Archexteriors vol 06 (高品质完整室外场景模型)DVD-4 新编_EA_室外_04Evermotion Archexteriors vol 07 (高品质完整室外场景模型)Evermotion Archexteriors vol 08 (高品质完整室外场景模型)DVD-5 新编_EA_室外_05Evermotion Archexteriors vol 09 (高品质完整室外场景模型)DVD-6 新编_EA_室外_06Evermotion Archexteriors vol 10 (高品质完整室外场景模型)DVD-7 新编_EA_室外_07Evermotion_Archexteriors_1_Mental Ray 室外场景模型MR版【专业材质贴图与视频教程共3DVD】DVD-1 新编_EA_专业材质贴图景观-01Evermotion ArchShaders Vol 1-3 [专业室内材质库]Evermotion Textures4ever Vol(1-3) [专业景观材质库]DVD-2 新编_EA_专业材质贴图景观及教程-02Evermotion SKIES HDRI [天空高动态范围贴图]Evermotion 商业CG专业材质1-2 [商业CG专业材质]Evermotion 3D People Vol 01 [三维人物]Evermotion Christmas tree [圣诞树3D模型]DVD-3 新编_EA_汽车模型及视频教程Evermotion HDModels Car vol 1 [高精度汽车模型]Evermotion HDModels Car vol 2 [高精度汽车模型]Evermotion Mental4ever [MentalRay视频教程]Evermotion Vray Video Tutorials [VR视频教学]。
USACO 2019 US Open银组Silver竞赛真题(中文)
USACO2019US O PEN C ONTEST,S ILVERP ROBLEM1.L EFT O UTFarmer John正在尝试给他的牛群拍照。
根据以往的经验，他知道这一工作往往结果不怎么样。
这一次，Farmer John购买了一台昂贵的无人机，想要拍一张航拍照。
为了使照片尽可能好看，他想让他的奶牛们在拍照时都朝向同一个方向。
奶牛们现在在一块有围栏的草地上排列成$N\times N$（$2\leq N\leq1000$）的方阵，例如：RLRRRLLLR这里，字符'R'表示一头朝右的奶牛，字符'L'表示一头朝左的奶牛。
由于奶牛们都挤在一起，Farmer John没办法走到某一头奶牛面前让她调转方向。
他能做的只有对着某一行或某一列的奶牛喊叫让她们调转方向，使得被叫到的这一行或列内的所有L变为R，R变为L。
Farmer John可以对任意多的行或列发号施令，也可以对同一行或列多次发令。
就如同Farmer John想象的，他发现他不可能让他的奶牛们都朝向同一个方向。
他最多能做的是让所有奶牛中除了一头之外都朝向相同的方向。
请找出这样的一头奶牛。
输入格式（文件名：leftout.in）：输入的第一行包含$N$。
以下$N$行描述了奶牛方阵的第$1\ldots N$行，每行包含一个长度为$N$的字符串。
输出格式（文件名：leftout.out）：输出一头奶牛的行列坐标，满足这头奶牛被调转方向的话，Farmer John就可以使他的所有奶牛都朝向同一个方向。
如果不存在这样的奶牛，输出-1。
如果存在多头这样的奶牛，输出其中行坐标最小的，如果多头这样的奶牛具有相同的行坐标，输出其中列坐标最小的。
输入样例：3RLRRRLLLR输出样例：11在这个例子中，位于第1行第1列（左上角）的奶牛是那头令人讨厌的奶牛，因为Farmer John 可以喊叫第2行和第3列来让所有奶牛都面向左侧，只有这一头奶牛面向右侧。
钢便桥计算书(midas Civil 2019建模)
钢便桥计算书(midas Civil 2019建模)1.1 受力模型及材料参数钢栈桥的验算采用有限元法，选取便桥的标准跨径作为计算模型，并利用midas Civil 2019计算程序建模进行验算。
1.1.1 跨径9m单排3根桩钢便桥结构模型图1.1-2为跨径为9m的单排3根桩便桥结构模型。
栈桥上部结构为贝雷梁结构，下部结构为钢管桩加型钢承重梁结构。
栈桥基础及桥墩全部采用φ630mm厚10mm的螺旋焊接钢管桩，钢管桩按单排3根桩桩布置。
横联及斜撑采用[20a槽钢，钢管桩顶设双拼I45a工字钢帽梁。
桩顶横梁上架设贝雷梁，采用单层3组每组2片总计6片贝雷架结构，每组贝雷架采用定制支撑架连接，相邻贝雷架组采用∠75×8角钢连接，间距为90+125+90+125+90cm形成主纵梁，贝雷梁上设按30㎝间距布置I25a工字钢分配横梁与桥面10mm厚钢板经焊接固定成型的6m宽模块。
1.1.2 材料参数铺装钢板厚度为10mm，材料为Q235钢。
分配横梁参数：材料为Q235钢，截面为I25a，长度为6m。
主梁参数：采用321型贝雷片，材料为16Mn钢。
贝雷梁支撑架参数：材料为Q235，材料为∠63×4角钢。
贝雷梁组间斜撑参数：材料为Q235，材料为∠75×8角钢。
桩顶横梁参数：材料为Q235钢，截面为2×I45a，长度为6m。
钢管桩参数：材料为Q235钢，管型截面为外径630mm，厚度为10mm，长度为13.4m。
根据《钢结构设计标准》GB-2017，钢材强度设计值可查表得：型钢材质均为Q235钢，其抗弯设计强度为215MPa，抗剪设计强度为125MPa。
贝雷片材质为16Mn钢，其容许弯应力为273MPa，容许剪应力为156MPa。
根据《公路钢结构桥梁设计规范》JTG D64-2015，挠度计算可查表得：2.边界条件钢管桩的底部固结；桩顶横梁和钢管桩采用弹性连接(刚性)；桩顶横梁和贝雷片弹性连接(刚性)；贝雷片和分配横梁采用弹性连接(刚性)。
2019美赛数学建模A题论文
Winter is approaching, may the dragon’s wings grow moreabundantSummaryIn the game of thrones, Daenerys Targaryen depicts the image of a dragon. In eastern and western cultures, the phenomenon of dragons is not uncommon. If dragons live in modern society, how can we raise these war monsters? Research, and applied the cross disciplines of biology, physics, and chemistry to build a mathematical model and solve it to achieve the maximum growth of the dragon. Of course, dragons do not exist in real life, so we likened pterosaurs, modern Aircraft and chemical burner to derive the specific physiological characteristics of the dragon to ensure the rationality and scientificity of the research.First, we studied the flight and fire-spitting models of dragons. Through analogical reasoning, our hypothetical dragon's fire-spitting principle is similar to modern alcohol flamethrowers. For dragon flight, we used fluid mechanics to get the dragon's flight speed. And glucose energy loss. Combining the two to get the energy loss model of the dragon. Second, we studied the basic physical characteristics of the dragon. For the relationship between the body length and body age of the dragon, we established an elastic model of growth. Because the weight and body length of dragons have upper and lower limits, in order to comply with basic ecology, we have defined the dragon's bone saturation value as the cut-off value, and conducted a segmented study. When studying the relationship between weight and body length, We know that the weight of the dragon is proportional to the cube of the body length. Then, because the dragon needs resources to replenish like other animals, we built a dragon's food supply model. Suppose that the three dragons have the same competitiveness and the daily sheep Resources are the same. According to ecology, when the number of sheep in a certain area reaches k / 2, we need to migrate the dragon. Finally, the temperature will affect the living environment of the dragon, so the dragon needs to followMigration was selected for changes in temperature, and we selected three areas of drought, cold, and warmth to study the dragon, and integrated the model of the regional area of the dragon by the appealing model.In addition, we wrote a letter to the author of the Song of Ice and Fire, giving some suggestions on the actual ecological foundation of the dragon, hoping to be adopted. Although the dragon does not exist in our real life, the dragon can be broken down into Part of our modern society. For the dragon's flying spitfire energy loss model, we can further study the aircraft's fluid mechanics and modern flamethrowers. The study of non-existent organisms also prepares us for the arrival of new species .table of ContentsWinter is approaching, may the dragon’s wings grow more abundant (1)Summary (1)table of Contents (2)1 Introduction (3)1.1 restatement (3)1.2 Problem Analysis (3)2 Assumptions and reasons (4)3 Symbol Definition (4)4. Mathematical modeling (5)4.1 About Dragon Flight and Spitfire Consumption (5)4.2 About the relationship between dragon's body length and weight and age (7)4.3 About Dragon's Food Supply (8)4.4 Regulating the area of dragons by region (9)5 Sensitivity analysis (10)6 Model evaluation and outlook (11)6.1 Model evaluation (11)6.2 Further discussion (12)7 to a letter from George RR Martin (12)8.Appendix: (13)8.1 References (13)8.2 Matlab code (13)1 Introduction1.1 restatementIn the magical TV series "Game of Thrones", Daenerys Targaryen, known as the Mother of Dragons, raised three dragons as an aggressive army. Dragons have always been the most mysterious monsters in Eastern and Western cultures, but if Dragons live in the present era, how should we feed the three dragons in pursuit of maximum growth? In this article, we assume that the growth rules of dragons are in line with basic biology. To study them, we build mathematical models to solve problem.a. Analyze the change of the dragon's weight length with age, and estimate the value of the dragon's weight length corresponding to the age group.b. Investigate the loss of self energy during dragon fire, flight, and breathing, so as to estimate the minimum supply value of dragon for external activitiesc. Dragons need food and survival areas like other animals in the real world. Through certain assumptions and calculations, we can determine the total amount of food that dragons need daily and the size of living areas in three areas.d. Sensitivity analysis: As temperature and climate change, dragons will also migrate to different regions. Therefore, we need to analyze the differences in the impact of dragons on the survival of arid regions, temperate regions, and cold regions.1.2 Problem AnalysisBecause dragons do not exist in real life, we need to use some things in the real world to compare dragons in order to achieve the purpose of studying dragons. In analyzing the biological morphological characteristics of dragons, we use the knowledge of ecology and basic elements of biology Let's conceive the basic biological characteristics of the dragon such as weight and body length. For the energy loss model of the dragon, we have studied three aspects to describe its loss. Here we compare the modern flamethrower and establish related chemical equations to achieve the research of the dragon. Spitfire loss. In addition, in TV series such as "Game of Thrones" we will find that dragons can fly in common sense, so we have derived the dragon's flight loss. Of course, all aerobic organisms can breathe. Dragons are no exception, so there is a loss of breathing to maintain body temperature. At the same time, in order to make up for the loss of dragons in daily activities, we have established a material reserve model, in which materials are cattle and sheep in real life, etc. Finally, during the cyclical changes in climate and food, the dragons we feed will also migrate to some extent, so we analyzed the impact of different regions on the growth of dragons.Into account various factors that we can more scientific training of dragons, have achieved our purpose.2 Assumptions and reasonsAfter a comprehensive analysis of the problem, in order to increase the enforceability, we make the following assumptions to ensure the rationality of our model establishment.2.1 Assumptions: The basic biological characteristics of dragons are in line with the law of biological growth. In modern life, the growth and development of dragons should also be similar to other animals and conform to basic biology.2.2 Assumption: The dragon will spit fire and fly, and its flight conforms to the physical environment of fluid mechanicsReason: In Game of Thrones, the image of the dragon was once able to fly and spit fire.2.3 Assumption: In the single field we are studying, the environment of a certain area will not change abruptly and maintain a dynamic stability.2.4 Hypothesis: Dragons are top predators in the food chain, but dragons do not cause devastating harm to the biosphere.2.5 Assumption: The weight distribution of the dragon is uniform, and the body length reaches 30 to 40 cm at the time of birth.Reason 2.6: We refer to ancient biology and some dinosaur fossils.2.7 Hypothesis: Except for the skull, heart, liver, lungs, kidneys, bones, etc., the sum of other body masses is proportional to the cube of height.Reason: The hypothesis is obtained by counting the relationship between body length and weight of modern organisms.2.8 Hypothesis: The dragon is a constant temperature animal whose body temperature is not affected by external factors.Reason: A few pterosaur fossils have traces of "hair" on the surface, while the dragons in Game of Thrones are similar to pterosaurs.2.9 Hypothesis: The dragon is fully aerobic during the flight to provide energy2.10 Hypothesis: A certain fixed ratio of the amount of energy that is not assimilated by the growth and metabolism of the dragon's breathing and other organisms2.11 Hypothesis: Dragon's Flight Similar to Modern Fighter3 Symbol Definition4. Mathematical modeling4.1 About Dragon Flight and Spitfire Consumption4.1.1 Proposed modelConsidering that dragons fly and spit fire during activities, we have established an energy loss model. Comparing the principle of dragon's spitfire with modern flamethrowers, modern flamethrowers consume hydrocarbons or alcohols. It does not cause any impact, so the dragon's fire-breathing principle is in line with the alcohol flame-thrower principle. Considering that the formaldehyde produced by the metabolism of methanol in the animal body is harmful to the body, we stipulate that ethanol is the fuel used by the dragon's flame. In the process, the relationship between the dragon's flight speed and glucose energy consumption is obtained according to fluid mechanics. In this process, we assume that the aerobic respiration is completely performed, and the energy consumed by the dragon due to flight is obtained according to the glucose consumption. In summary, the dragon energy loss model is obtained. .4.1.2 Establishment and Solution of Dragon's Spitfire ModelThe thermochemical equation for ethanol combustion is: C2H5OH (l) + 3O2 (g) = 2CO2 (g) + 2H2O (l) △H = -12KJ / gSpecify the energy released per unit mass of ethanol combustion x1When the dragon spit fire in unit time t, the unit mass of ethanol consumption is a fixed valueThe energy consumed by the fire time t1 is w1The mass consumed by the fire time T1 is m4Let the energy emitted by the combustion of unit mass of ethanol be w1 'Then W1 = x1 * tm4=W1/W1’Solve m4 = x1 * t / W1 '4.1.3 Establishment and Solution of Dragon Flight ModelDuring the flight of the dragon, it will be affected by the air resistance. In the ideal situation, the dragon's flight can be considered as a uniform acceleration and then a uniform speed, and it will decelerate when it is about to reach its destination.When Long uniform acceleration is specified, the acceleration is aSince the flight of the dragon is similar to that of a fighter, a = 30m / s ^ 2The speed of the dragon during uniform motion is v0The total flight length of the dragon during flight is sBecause air resistance is proportional to the speed of movement, that is, F1 = k * v (where k is a constant)Since the dragon's flight is similar to an airplane, we can get k = 3.2325Available according to the relevant kinematic formulaThe flying distance of the dragon during uniform acceleration is s1 = (v0) ^ 2 / 2aThe flying distance of the dragon during uniform deceleration is s3 = (v0) ^ 2 / 2aThe flying distance of the dragon during uniform motion is s2 = s-s1-s3Average air resistance during uniform acceleration F1 '= k * (0 + v0) / 2The average air resistance during uniform motion is F1 '' = k * v0Average air resistance during uniform deceleration f1 '' '= k * (v0 + 0) / 2According to the law of conservation of energyThe energy w2 consumed by the dragon during flight is all used for air resistance workW2=F1’*s1+F1’’*s2+F1’’’*s3Solve W2 = 3.2325 * v0 * s-3.2325 * (v0) ^ 3 / (2 * 30)During the flight of the dragon, the principle of energy provided by aerobic respiration isC6H12O6+6O2=6CO2+6H2OAmong them, the energy produced when 1g of glucose is completely consumed is 16KJThen the weight consumed in this process is m6 = W2 / 16[v,s]=meshgrid(0:0.1:100;0:0.1:100);m=3.2325*v*s-3.2325*v^3/60mesh(v,s,m)4.2 About the relationship between dragon's body length and weight and age4.2.1 Proposed ModelFirst, in order to study the relationship between the weight, length, and age of the dragon, that is, morphological characteristics, we established a model of elasticity during growth. The above-mentioned change curve is continuous, so we use the weight of the dragon at birth, and consider the weight and length of the dragon. The relationship between age changes can be used to derive the normal weight and body length of dragons in all ages. When analyzing the weight changes of dragons, biological knowledge shows that the amount of assimilation of the dragon is equal to the intake amount minus the amount of unassimilated amount Considering that the growth rate of the dragon in adulthood is a watershed, we use the saturation value of the dragon's head, heart, and liver as a cutoff value to estimate the relationship between the dragon's weight and age, respectively. When studying the body length of the dragon, according to the existing morphological knowledge, the head to hip of the dragon is used as the length standard. Because the weight of the dragon is proportional to the cube of the dragon's length, we get the weight and length Functional relationship. Of course, the daily weight gain of the dragon must be less than the daily energy consumption. In summary, we have a dragon intake model.4.2.2 Model establishmentSpecify the weight of the dragon as mDragon was born with a weight of m0 (known m0 = 10kg)Assume that the mass of cattle and sheep fed by a train every day is m2The assimilation amount of the dragon is fixed at a%A certain fixed ratio of the amount of unabsorbed energy due to growth and metabolism of organisms such as dragon's respiration, recorded as b%The weight gain of the dragon is m 'The sum of the weight of the dragon's head, heart, liver, lungs, kidneys, bones, etc. m1 increases with age y until adulthoodDragon is y1 when he is an adultThe growth rate of m1 is v1The mass of m1 at birth is m0Before the dragon reaches y1m1=m0+v1*yAfter the dragon reaches y1m1’=m0+v1*y14.2.3 Model Solvingm’=m2*(1-a%)*(1-b%)-m4-m6So the weight of the dragon m = m '+ m0Except for the dragon, except for the head, heart, liver, lungs, kidneys, bones, etc., the sum of other body masses is proportional to the cube of height, and the body length is recorded as l When the age of the dragon does not reach y1, l = (m-m1) ^ (1/3)When the age of the dragon reaches y1, l '= (m-m1') ^ (1/3)M2 =y=0:0.1:20function[y]= (m2*(1-a%)*(1-b%)-m4-m6-v1*y)y=20:0.1:100function[y]= (m2*(1-a%)*(1-b%)-m4-m6-v1*20)power(y,1/3)4.3 About Dragon's Food Supply4.3.1 Proposed modelBased on the above analysis, we studied the living area of the three dragons in the region andtheir impact on the ecological community in the region. For the sake of research, we assume that the other creatures in the region are cattle and sheep, and the competitiveness of the three dragons is comparable, Being a top predator in the food chain.4.3.2 Model establishmentThe local food chain can be approximated as: grass → cow or sheep → dragonAssume that the weight of the grass in the arid region, the warm temperate region, and the Arctic region is the same as m8.Remember that the mass of each cow and sheep is the same as m7We provide the same initial number of cattle and sheep in all three regionsAssume that the daily growth rate of cattle and sheep is c%The initial number of cattle and sheep is n1And n1 is the number of populations reaching k in the regionDragons live in this area. When the number of cattle and sheep reaches k / 2, in order to ensure the balance of the ecological environment, the dragons need to be moved to other regions.4.3.3 Model SolvingThe initial amount of cattle and sheep on day 1 is: n1The initial amount of cattle and sheep on the second day is: N2 = (N1-3 * m2 / m7) * (1 + c%) The initial amount of cattle and sheep on the third day is: N3 = ((N1-3 * m2 / m7) * (1 + c%)-3 * m2 / m7) * (1 + c%)……From this we can get the initial amount of Ni of cattle and sheep on day iI can be solved by the equation Ni = K / 2That is, the dragon needs to change a living area after living in the area for i days.4.4 Regulating the area of dragons by region4.4.1 Proposed modelIn order to ensure the normal growth of the dragon, we provide fixed-quality cattle and sheep as the supply of resources for the survival of the dragon region, and assume that the number of cattle and sheep is proportional to the size of the regional living area. Considering the growth rate of cattle and sheep, we have established a differential The equation draws the relationship between the growth rate of cattle and sheep and the age of the dragon. However, cattle and sheep will reach a growth saturation value at a certain moment, we will consider it in segments to ensure that the data is more scientific. In order to comply with ecology, cattle The supply of sheep should also have a lower limit. In summary, we have established a dragon-cow-sheep-living area function model.4.4.2 Model establishmentRemember that the assimilation rate of cattle and sheep grazing in this area is d%Because the solar energy received by the surface area of the three areas is different, the total area required for the grass under the same quality conditions is different. The utilization rate of the solar energy is required to be e% (0.5 <e <1 under the natural conditions of the search data)The solar energy per unit area in the arid area is q1Unit area solar energy in warm zone is q2Solar energy per unit area in the Arctic is q34.4.3 Model SolvingAccording to the utilization of solar energy, we can find:Area required to support the arid areas where the three dragons live: S1 = m8 / (q1 * e%)Warm zone: S2 = m8 / (q2 * e%)Arctic region: S3 = m8 / (q3 * e%)5 Sensitivity analysisImpact of climatic conditions on dragon lifeThe effect of climatic conditions on dragon growth can be obtained from the logistic growth model dm/dt=r*m*(1-m/k)That is m = 15 / (4 * t + 20);(Where m is the mass that the dragon can eventually grow into)Where m0 = 10 (k is the maximum carrying capacity of the ecosystem and r is a parameter of the environmental carrying capacity)k is 0.75r is 0.8dm/dt=0.8*m*(1-m/0.75)t=0:0.1:100;m=15./(4*t+20);plot(t,m)6 Model evaluation and outlook6.1 Model evaluationFor the idealized model of Yanglong, we have performed various aspects of modeling and solving, and the scope is relatively broad. Of course, the content has been streamlined to facilitate understanding and application. We have used physical and biological models based on The mathematical formulas are also encountered in the middle school stage. In these more basic models, we have solved efficiently, and at the same time, for the interdisciplinary problems of question a, we have considered the field that the ideal biology of dragons may involve and solve The process is relatively complete. In addition, the four models are closely related and logical. First, we consider the consumption of dragons in daily life, and use the results of consumption to calculate the weight and length of the dragon at various ages. In order to meet the requirements of all ages, we have established the ecological supply model of dragons, and discussed the problem of periodic alternating fields. Second, the fields are also scoped. Therefore, we calculated the scope of three areas with different climates. Interval problems. However, the models we build are idealized, the data is also streamlined, and the assumptions set are also fallible. In reality,The data is diverse and complex, and our considerations are obviously lacking, and further optimization is needed in the later stage. In summary, the model we built is very consistent with the solution of the problem. Although there are some flaws, it does not affect the specific Specific analysis of the problem.6.2 Further discussionCombining the models and evaluations described above, we will improve in the later stages. If this model is used in a specific environment, by statistic large amounts of real data, we can optimize the model. At the same time research also It will be more scientific and rigorous, and it will be more efficient for raising a fictional creature.7 to a letter from George RR MartinDear George RR MartinHope you are wellAfter reading the Song of Ice and Fire, we watched the "Game of Thrones". We became very curious about the mysterious giant that appeared in it-the dragon. Dragons are not uncommon in Eastern and Western cultures. In previous impressions However, there are few studies on dragons. So if we imagine that dragons live in modern times, what would it look like?According to the description of the dragon in the novel, we discussed the following questions. What are the ecological impacts and requirements of the dragon? What is the energy consumption of the dragon, what are their calorie intake requirements? How much area is needed to support the three dragons? Energy loss during fire? In response to these problems, we constructed a multivariate non-linear objective programming model of dragon's growth index and function, size, diet, growth changes, and other animal-related features. Considering the physical characteristics of dragons, we will Its fire-spitting ability is analogized to modern flame-throwers to ensure scientific and rational research.Based on these, we have established a mathematical model. The weight and length of the dragon also grows with the age of the dragon. When the dragon grows slowly at the initial 10 kilograms, the mass of sheep it needs each year also varies The growth of the supply chain of resources and the size of the ecological community should also change. The fire and flight of the dragon will also have a certain impact on the ecological environment. As the dragon and other creatures will migrate with changes in temperature, we choose The three regions of the cold zone, temperate zone and arid zone were taken as key research objects to find out the impact of climate change on Long.Therefore, we make the following suggestions, hoping that the survival of the dragon in the realm of science is more reasonable and scientific.When the herd resource is saturated, the dragon needs to expand the area living area.Dragons like warm, hydrated areas, and migrate to warm areas in the cold winter.A dragon has a certain weight and length when it is just born, and it will grow over time, but it also has an upper limit. It cannot grow endlessly.The daily energy intake of the dragon is limited, and the dragon spitfire flight consumes energy, which requires that the dragon's flight distance and spitfire time are limited, and it is related to the age of the dragon body.Because the living conditions of the three areas are different, the unit area will also receive solar energy differently, resulting in different resource distributions in each area, which means thatthe speed of dragon growth should also be different in different areas.The environmental carrying capacity of each area is limited, and the dragon does not stay in one place for long.The above content is the result of our research on the Queen of Dragons. We sincerely hope that you can adopt it, and we have been looking forward to your new book.Your fans: 27 groupsJanuary 7, 20208.Appendix:8.1 References1) Chen Yun.Research on Environmental Carrying Capacity of Yuhuan County [j] .Energy and Energy Conservation, 2014 (4): 31-33.2) Zhu Ziqiang.Aerodynamic design of modern aircraft [m] .Beijing: National Defense Industry Press, 2011-10-13) Jin Lan.Environmental Ecology [m] .Higher Education Press, 19928.2 Matlab codeModeling the flight of a dragon[v,s]=meshgrid(0:0.1:100;0:0.1:100);m=3.2325*v*s-3.2325*v^3/60mesh(v,s,m)Sensitivity Analysis of the Impact of Climate Conditions on Lifet=0:0.1:100;m=15./(4*t+20);plot(t,m)。
钢便桥计算书(midas Civil 2019建模)
第1章钢便桥计算书1.1受力模型及材料参数钢栈桥验算采用有限元法，选取便桥的标准跨径作为计算模型，利用midas Civil 2019计算程序建模进行验算。
1.1.1跨径9m单排3根桩钢便桥结构模型图1.1-2 跨径9m单排3根桩便桥结构模型桥型1：栈桥上部结构为贝雷梁结构，下部结构为钢管桩加型钢承重梁结构。
栈桥基础及桥墩全部采用φ630mm厚10mm的螺旋焊接钢管桩，钢管桩按单排3根桩桩布置。
横联及斜撑采用[20a槽钢，钢管桩顶设双拼I45a工字钢帽梁。
桩顶横梁上架设贝雷梁，采用单层3组每组2片总计6片贝雷架结构，每组贝雷架采用定制支撑架连接，相邻贝雷架组采用∠75×8角钢连接，间距为90+125+90+125+90cm形成主纵梁，贝雷梁上设按30㎝间距布置I25a工字钢分配横梁与桥面10mm厚钢板经焊接固定成型的6m宽模块。
1.1.2材料参数铺装钢板厚度10mm，材料Q235钢。
分配横梁参数：材料Q235钢，截面I25a，长度6m。
主梁参数：采用321型贝雷片，材料为16Mn钢。
贝雷梁支撑架参数：材料Q235，材料为∠63×4角钢。
贝雷梁组间斜撑参数：材料Q235，材料为∠75×8角钢。
桩顶横梁参数：材料Q235钢，截面2×I45a，长度6m。
钢管桩参数：材料Q235钢，管型截面（外径630mm，厚度10mm）长度为13.4m。
根据《钢结构设计标准》GB50017-2017，钢材强度设计值可查表得：型钢材质均为Q235钢，其抗弯设计强度a 215][MP =σ，抗剪设计强度[]a 125MP =τ。
贝雷片材质为16Mn 钢，其容许弯应力[]a 273MP =σ，容许剪应力[]a 156MP =τ。
根据《公路钢结构桥梁设计规范》JTG D64-2015，挠度计算可查表得：2.边界条件钢管桩的底部固结；桩顶横梁和钢管桩采用弹性连接(刚性)； 桩顶横梁和贝雷片弹性连接(刚性)； 贝雷片和分配横梁采用弹性连接(刚性)。
19年卷三英语作文模板
As a high school senior, Ive had my fair share of English exams, and one thing that has always been a part of our preparation is the use of templates for writing essays. The year 2019 was no different, and the third set of English papers had its own unique template that we used to structure our essays effectively. Heres a detailed look at how I approached essay writing using the 2019 Year 3 English exam template.IntroductionThe introduction is the first impression you give to the reader, and its crucial to make it count. I started by presenting a general statement about the topic, which was usually a social issue or a phenomenon. For instance, if the topic was about the impact of technology on education, I would begin with a statement like, In the digital age, technology has become an integral part of our lives, reshaping the way we learn and interact.Thesis StatementFollowing the general statement, I would present my thesis, which is the main argument or point of the essay. Its important to be clear and concise here. For example, This essay will explore the positive and negative impacts of technology on the educational landscape.Body ParagraphsThe body of the essay is where I expanded on the thesis statement by presenting different points. Each body paragraph would focus on a single argument or piece of evidence. I made sure to follow a clear structure within each paragraph:1. Topic Sentence: This is the main idea of the paragraph, which directly supports the thesis. For example, One significant advantage of technology in education is the accessibility of information.2. Explanation: I would then explain the topic sentence in more detail, providing context or background information.3. Evidence: To support my argument, I included relevant examples, statistics, or quotes from experts.4. Analysis: This is where I analyzed the evidence, explaining why it supports my argument and what it implies.5. Transition: To move smoothly to the next point, I used transition phrases like Furthermore, However, or On the other hand.CounterargumentSometimes, its beneficial to acknowledge the opposing viewpoint to strengthen your own argument. I would dedicate a paragraph to presenting the counterargument, followed by a refutation that reinforces my thesis.ConclusionIn the conclusion, I would restate the thesis and summarize the main points of the essay. I also made sure to end on a strong note, often with a call to action or a thoughtprovoking statement. For example, As we continue to embrace technology in education, it is crucial to balance itsbenefits with the need to preserve traditional learning methods.Personal TouchTo make the essay more engaging, I tried to add a personal touch or anecdote related to the topic. This could be a personal experience, a quote from someone I admire, or a reflection on how the topic affects me or my peers.Language and StyleUsing a variety of sentence structures and vocabulary was essential to make the essay more interesting. I also paid attention to the tone, aiming for a balance between formal academic writing and a conversational style that would resonate with the reader.ProofreadingLastly, I always made time to proofread my essay, checking for grammatical errors, clarity of expression, and adherence to the essay prompt.Using this template, I found that my essays were wellstructured, easy to follow, and effectively communicated my ideas. It was a valuable tool during my high school years and something I still apply in my writing today.。
构建模型的英语
构建模型的英语Building a Model: Key Steps and ConsiderationsIntroduction:Building a model is a crucial process in various fields such as machine learning, data analysis, and statistical modeling. It involves constructing a representation of a system or phenomenon to understand, predict, or analyze its behavior. In this article, we will discuss the key steps and considerations involved in building a model.1. Defining the Problem:The first step in model building is to clearly define the problem or objective. This involves understanding what needs to be achieved, identifying the available data, and setting realistic expectations. A well-defined problem statement helps guide the entire modeling process.2. Data Collection and Preparation:Once the problem is defined, the next step is to gatherthe relevant data. This may involve sourcing it from various databases, utilizing existing datasets, or conducting experiments to generate new data. Data preparation is equally crucial, which includes cleaning, transforming, andformatting the data in a suitable manner for modeling.3. Exploratory Data Analysis (EDA):EDA involves analyzing the collected data to understandits characteristics, identify patterns, and detect outliers.It helps to gain insights into the data, validate assumptions, and select appropriate modeling techniques.4. Feature Selection and Engineering:Feature selection refers to the process of identifyingthe most relevant variables or features from the data that contribute significantly to the outcome. Feature engineeringinvolves creating new features or transforming existing ones to improve the model's performance. This step requires domain knowledge and creativity.5. Selecting a Modeling Technique:Choosing an appropriate modeling technique depends on the nature of the problem, available data, and desired outcome.It could range from traditional statistical methods such as linear regression and decision trees to more advanced techniques like neural networks and deep learning.6. Model Training and Evaluation:Once the modeling technique is selected, the model needs to be trained using the prepared data. This involvessplitting the data into training and validation sets,defining performance metrics, and fine-tuning the model parameters. After training, the model's performance is evaluated using various metrics such as accuracy, precision, recall, or mean squared error.7. Model Optimization:Model optimization aims to improve the model's performance by fine-tuning its parameters or exploring different algorithms. Techniques like cross-validation, hyperparameter tuning, and regularization can be employed to prevent overfitting and achieve better generalization.8. Model Deployment and Monitoring:After optimizing the model, it is deployed for real-world usage, integrating it into the existing architecture or systems. It is important to continuously monitor the model's performance, assess its accuracy, and retrain or update it periodically to adapt to changing data patterns.9. Model Interpretation and Communication:Model interpretation helps in understanding the factors influencing the model's predictions and gaining insights. It is crucial for decision-making and explaining the model'soutcomes to stakeholders. Effectively communicating the model's results and limitations is essential for gainingtrust and facilitating its practical implementation.Conclusion:Building a model involves a series of well-defined steps, from problem definition to model interpretation. Each step requires careful consideration and expertise in order to develop an accurate and reliable model. By following these steps and considering the specific requirements of the problem at hand, one can build effective models to gain insights, make predictions, or solve complex problems in various industries.。
产品建模总结范文英文
Introduction:Product modeling is a crucial process in the development of any product, whether it is a physical good or a software application. This summary aims to provide an overview of the key steps and considerations involved in product modeling, based on our recent project experience.1. Requirement Analysis:The first step in product modeling is to conduct a thorough requirement analysis. This involves understanding the needs and expectations of the end-users, as well as identifying the functional and non-functional requirements of the product. In our project, we conducted extensive market research and user interviews to gather valuable insights and ensure that our product meets the users' expectations.2. Conceptual Design:Once the requirements are identified, the next step is to create a conceptual design. This involves defining the basic structure and features of the product, as well as its interface and user experience.In our case, we utilized various design tools and techniques, such as sketching, wireframing, and prototyping, to visualize the product's conceptual design and gather feedback from stakeholders.3. Detailed Design:After finalizing the conceptual design, the detailed design phase begins. This phase involves specifying the technical requirements, components, and materials needed to build the product. We carefully analyzed the design constraints and ensured that the product's performance, durability, and cost were optimized. Additionally, we considered the manufacturing process and ensured that the design was feasible and cost-effective.4. Simulation and Analysis:To validate the product's performance and identify potential issues, we conducted simulations and analyses using specialized software tools.This allowed us to simulate real-world scenarios and assess theproduct's behavior under various conditions. By identifying and addressing potential problems early in the design process, we minimized the risk of costly redesigns and delays.5. Prototyping and Testing:Once the detailed design was complete, we built a prototype to test the product's functionality and user experience. The prototype allowed us to validate our design decisions and gather feedback from users. We conducted extensive testing, including functional testing, usability testing, and performance testing, to ensure that the product met our requirements and user expectations.6. Iterative Refinement:Based on the feedback received during the testing phase, we madeiterative refinements to the product design. This involved adjusting the features, interface, and performance of the product to address any issues identified during testing. The iterative process allowed us to improve the product's quality and ensure that it met the users' needs.7. Documentation and Reporting:Throughout the product modeling process, we maintained comprehensive documentation of our design decisions, simulations, and testing results. This documentation was crucial for ensuring consistency and facilitating communication among team members. Additionally, we prepared detailed reports to present the project's progress, findings, and recommendations to stakeholders.Conclusion:In conclusion, product modeling is a complex and iterative process that requires careful planning, analysis, and collaboration. By following a systematic approach and considering various factors such as user requirements, design constraints, and performance, we were able to develop a high-quality product that meets the needs of our target audience. The insights gained from this project will be invaluable inour future endeavors and contribute to the continuous improvement of our product development process.。
2019亚太数学建模B题(英文)
2019 Asia and Pacific Mathematical Contest in ModelingProblem BAnalysis and Decision-making of Regional Economic Vitalityand Its Influencing FactorsThe regional (or urban or provincial) economic vitality is an important part of regional comprehensive competitiveness. In recent years, in order to improve the economic vitality, some regions have launched many preferential policies for stimulating the economy vitality, such as reducing the investment attraction approval steps, providing the capital support to start-ups and lowering the settlement threshold to attract the talented. However, due to different resource endowments, these policies have different effects in different regions. How to seize the key factors and effectively improve the regional economic vitality is a worth study topic.In order to study how to improve the regional economic vitality, we have obtained some data. Please build a suitable model and solve the following problems based on these data and your own data obtained through survey.1. The regional (or urban or provincial) economic vitality is affected by variety of factors. Takea region (or city or province) as an example, please build the suitable relational model of influencing factors of economic vitality, and study the program of action to improve the regional economic vitality. Analyze the effects on the regional economic vitality change from the perspective of changing trend of population and enterprise vitality.2. Select a region (or city or province), and analyze the short-term and long-term effects of economic policies transformation on the economic vitality of such region (or city ore province) based on the suitable data surveyed by you.3. Measuring the regional economic vitality is a complex issue. Please select the suitable index system, establish the mathematical model which analyzes and measures the regional (or urban or provincial) economic vitality, and rank the economic vitality of cities in Attachment 3.4. If you are a decision-maker of regional economic development, according to the conclusions for Problems 1-3, provide a development proposal for the region (or city or province) discussed in Problem 2 so that the economic vitality in this region presents the benign sustainable development and the regional competitiveness is stronger.Attachment(5 attachments in total)Attachment 1The quantity of enterprises is an important index to measure the regional economic vitality. The quantity of enterprises has a direct effect on the available job opportunities, and to what extent the resource circulation is promoted, and decides the economic benefits. According to the data, from 2009 to 2018, there were 40,176,400 registered and established enterprises (excluding individual business, the same below) in total in 31 provinces/municipalities directly under the Central Government/autonomous regions (excluding Hong Kong, Macau and Taiwan Province). As of September 2019, 9,753,800 enterprises were cancelled (cancellation rate of 24.28%), and there were still 30,422,600 surviving enterprises. The quantity of enterprises which were registered and established from 2009 to 2018 and survive up in 2019 is as follows (Unit: 10,000):Table 1: The quantity of enterprises which were registered and established from 2009 to 2018 and surviveup in 2019Province Quantity of Surviving Enterprises in 2019 (Unit: 10,000)Heilongjiang 43.6Jilin 44.4Liaoning 76.1Beijing 118.3Tianjin 43.7Inner Mongolia 42.1Xinjiang 31.8Qinghai 10.0Tibet 6.7Ningxia 15.1Shanxi 55.6Hebei 134.8Shandong 243.9Henan 146.3Shaanxi 73.0Gansu 43.3Sichuan 122.4Chongqing 69.8Hubei 105.3Anhui 113.8Jiangsu 269.4Shanghai 157.4Zhejiang 188.5Guizhou 64.0Hunan 79.9Jiangxi 66.1Fujian 105.9Yunnan 60.6Guangxi 68.7Guangdong 420.4Hainan 21.5Attachment 2Since 2013, the growth of quantity of enterprises in China has accelerated. Although the growth in different economic regions is obviously different, the annual quantity of newly-added enterprises in all regions is more than that of last year basically. In terms of region, except the total quantity, in the difference of average quantity of newly-added enterprises per province in four economic regions, the eastern region still maintains a great advantage: the provinces in the eastern region have the largest average registration quantity of enterprises per province and the highest growth, followed by the central region. In the west and northeast, the enterprise vitality is relatively weak. The average quantity of newly-added enterprises per province in the northeast may be surpassed by the western region in recent years. In general, there is still a relatively great difference in the enterprise vitality between regions. However, regardless of region, the annual quantity of newly-added enterprises from 2009 to 2018 was relatively stable.Four economic regions are divided as follows:Eastern region: Beijing, Hebei, Tianjin, Shandong, Jiangsu, Shanghai, Zhejiang, Fujian, Guangdong, HainanCentral region: Shanxi, Henan, Hubei, Hunan, Jiangxi, AnhuiWestern region: Chongqing, Sichuan, Guangxi, Guizhou, Yunnan, Shaanxi, Gansu, Ningxia, Xinjiang, Qinghai, TibetNortheastern region: Heilongjiang, Jilin, Liaoning, Inner MongoliaTable 2: Trend in Incremental Changes to Enterprises in Four Economic Regions from 2009 to 2018(Unit: 10,000)Year EasternRegionCentralRegionNortheasternRegionWesternRegion2009 7.9 4.4 3.3 2.32010 9.4 5.0 3.6 2.62011 10.3 5.6 3.8 2.92012 9.9 5.7 3.6 3.12013 12.7 7.2 4.6 3.72014 19.5 11.1 7.0 6.02015 23.8 12.9 7.1 7.02016 30.3 16.4 8.6 8.62017 32.8 19.6 10.1 9.82018 35.8 22.6 10.3 10.5Attachment 3If we look away from economic region and province, and focus on city, in addition to Beijing, Shanghai, Guangzhou and Shenzhen, the second-tier cities are also worth attention. The data of stock and cancellation distribution of enterprises in Beijing, Shanghai, Guangzhou and Shenzhen and some second-tier cities are given as follows. (Unit: 10,000)Table 2: The data of stock and cancellation distribution of enterprises in Beijing, Shanghai, Guangzhou andShenzhen and some second-tier cities (Unit: 10,000)CityQuantity of Newly-established Enterprisesfrom 2009 to 2018Quantity of SurvivingEnterprises in 2019Quantity of CancelledEnterprises from 2009to 2018Shanghai 204.8 157.4 47.4 Shenzhen 203.1 174.1 29.0 Beijing 152.1 118.3 33.8 Guangzhou 110.2 89.6 20.6 Chongqing 97.5 69.8 27.7 Chengdu 85.0 60.6 24.4 Nanjing 64.6 55.8 8.8 Hangzhou 64.1 48.7 15.4 Suzhou 63.8 53.6 10.2 Tianjin 62.0 43.7 18.3 Qingdao 55.6 41.0 14.6 Dongguan 53.4 43.4 10.0 Zhengzhou 53.3 43.1 10.2 Wuhan 52.6 39.8 12.8Xi’an 51.4 37.5 13.9Ningbo 44.4 31.1 13.4Changsha 36.8 28.5 8.3Shenyang 33.4 21.8 11.6Kunming 33.2 23.5 9.7Attachment 4The registered capital is an index to measure the enterprise size. In the distribution of enterprise size, there is not so large difference as imagined between the second-tier cities and Beijing, Shanghai, Guangzhou and Shenzhen. The distribution data of registered capital of enterprise entity are given as follows:Table 3: Distribution Data of Registered Capital of Enterprise Entity from 2009 to 2018 (Unit: 10,000)Nationwide Beijing Shanghai Guangzhou Shenzhen Second-tier Cities>10,000,000 9% 13% 9% 9% 8% 9%5,000,000-10,000,00013% 16% 14% 11% 12% 12%2,000,000-5,000,00016% 16% 16% 13% 12% 15%1,000,000-2,000,00021% 21% 22% 25% 25% 22%0-1,000,000 40% 35% 39% 42% 44% 42%Attachment 5How to narrow the difference in the quantity of enterprises between the second-tier cities and Beijing, Shanghai, Guangzhou and Shenzhen? “Investment attraction” and “talent attraction policy” may be common methods. Therefore, the “talent attraction” between cities presently becomes increasingly fierce. In fact, the resident population in a region is closely related to the quantity of enterprises in this region. The data of resident population in 2019 are given as follows.Table 4: Data of Resident Population and Quantity of Surviving Enterprises in Some Second-tier Cities in2019City Quantity of Surviving Enterprises in 2019Unit: 10,000Resident Population in 2019Unit: 10,000Shanghai 157.4 2419.70 Shenzhen 174.1 1190.84Beijing 118.3 2172.9 Guangzhou 89.6 1404.35 Chongqing 69.8 683.07 Chengdu 60.6 1194.05 Nanjing 55.8 827.0 Hangzhou 48.7 787.5 Suzhou 53.6 1068.4 Tianjin 43.7 1562.12 Qingdao 41.0 920.4 Dongguan 43.4 826.1 Zhengzhou 43.1 972.4 Wuhan 39.8 1091.4 Xi’an 37.5 992.32 Ningbo 31.1 787.5 Changsha 28.5 731.15 Shenyang 21.8 752 Kunming 23.5 667。
新疆三模2019英语作文
新疆三模2019英语作文Here is the English essay based on the given title "New Xinjiang 2019 English Essay" with a word count of over 600 words:The vast and diverse region of Xinjiang has long captivated the hearts and minds of people across China and the world. As one of the country's most dynamic and rapidly developing areas, Xinjiang has undergone remarkable transformations in recent years, emerging as a vibrant hub of cultural exchange, economic progress, and social innovation. In the year 2019, this remarkable region once again stepped into the spotlight, showcasing its remarkable strides and inspiring a new generation of thinkers, dreamers, and doers.At the heart of Xinjiang's remarkable journey lies a deep commitment to fostering a harmonious and inclusive society. The region has made significant strides in promoting ethnic unity, religious tolerance, and cross-cultural dialogue. Through targeted educational initiatives, investment in infrastructure, and a renewed focus on sustainable development, Xinjiang has been able to bridge the divides that once existed, creating a tapestry of diverse communities that thrive together.One of the most striking aspects of Xinjiang's transformation has been the remarkable advancements in the field of education. The region has invested heavily in modernizing its educational system, ensuring that students from all backgrounds have access to high-quality learning opportunities. From state-of-the-art schools and universities to innovative vocational training programs, Xinjiang has become a hub of educational excellence, producing a new generation of skilled professionals, entrepreneurs, and innovators.Alongside its educational achievements, Xinjiang has also emerged as a powerhouse of economic growth and development. The region's strategic location at the heart of the Silk Road has enabled it to become a hub of international trade and commerce, attracting investment from across the globe. From the development of cutting-edge industries such as renewable energy and advanced manufacturing to the flourishing of traditional sectors like agriculture and tourism, Xinjiang's economic landscape has been transformed, creating new opportunities for its people and contributing to the overall prosperity of China.Underpinning Xinjiang's remarkable progress has been a steadfast commitment to sustainable development and environmental protection. The region has implemented groundbreaking initiatives to address pressing environmental challenges, such as water scarcity, desertification, and air pollution. Through the deployment ofinnovative technologies, the promotion of eco-friendly practices, and the establishment of protected natural areas, Xinjiang has demonstrated its dedication to preserving the delicate balance of its ecosystems, ensuring a sustainable future for generations to come.At the same time, Xinjiang has also emerged as a vibrant cultural hub, celebrating the rich tapestry of its diverse heritage. From the breathtaking landscapes of the Tianshan Mountains to the ancient oasis cities that dot the region, Xinjiang has become a destination of choice for cultural enthusiasts, art lovers, and adventure seekers alike. The region's unique blend of Uyghur, Han, Kazakh, Kyrgyz, and other ethnic influences has given rise to a rich tapestry of music, art, cuisine, and traditions that captivate visitors from around the world.As Xinjiang continues to evolve and grow, it stands as a shining example of what can be achieved when a region embraces the principles of inclusivity, innovation, and sustainable development. The remarkable progress made in 2019 has not only transformed the lives of the people of Xinjiang but has also inspired others to follow in its footsteps, embracing the infinite possibilities that lie ahead. With a deep commitment to building a brighter future, Xinjiang's journey is one that promises to continue capturing the imagination of people everywhere, serving as a beacon of hope and progress in an ever-changing world.。
建模英文名词
建模英文名词Building Models and Understanding English TerminologyThe field of modeling encompasses the creation of representations that capture the essential features of a system or phenomenon. These models can take various forms, ranging from physical scale models to abstract mathematical representations. In the context of learning and mastering the English language, the process of building models can be a powerful tool for understanding and effectively using English terminology.One of the key aspects of modeling is the ability to simplify complex systems or concepts into more manageable and understandable components. This is particularly relevant when it comes to learning English vocabulary and grammar. By breaking down words, phrases, and grammatical structures into their constituent parts, learners can gain a deeper understanding of how the language works and how to apply it effectively.For example, when learning a new English word, a learner can create a mental model that includes the word's pronunciation, spelling, part of speech, and meaning. By understanding the various elements thatmake up the word, the learner can more easily recall and use it in appropriate contexts. This modeling approach can be extended to more complex linguistic structures, such as sentence patterns or idiomatic expressions.Moreover, the process of building models can help learners develop critical thinking skills and problem-solving abilities. As they engage in the modeling process, they must analyze the language, identify patterns, and make connections between different elements. This active engagement with the language can lead to a more robust understanding and the ability to apply what has been learned in various situations.Furthermore, the use of visual aids and other modeling tools can greatly enhance the learning experience. Diagrams, charts, and other graphical representations can help learners visualize the relationships between different English concepts, making them more accessible and easier to remember. This can be particularly useful for visual learners or for complex grammatical structures that may be challenging to grasp through textual explanations alone.In addition to the cognitive benefits, the process of building models can also foster a sense of ownership and agency in the learning process. By actively engaging in the modeling process, learners take a more active role in their own language acquisition, which can leadto increased motivation, self-confidence, and a deeper appreciation for the nuances of the English language.In conclusion, the process of building models can be a powerful tool for mastering English terminology. By breaking down complex linguistic concepts into more manageable components, learners can develop a deeper understanding of the language, improve their problem-solving skills, and enhance their overall language proficiency. As learners continue to engage in this modeling process, they can unlock new levels of linguistic understanding and become more effective communicators in English.。