数学建模美赛获奖论文

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2021数学建模国家一等奖论文(B)

2021数学建模国家一等奖论文(B)上海世博会影响力的定量评估摘要本文是一个对上海世博会影响力的定量评估问题，首先我们收集了与世博会有关的数据，如国内来沪旅游人数，国外来沪旅游人数等。

并用灰色预测对相应的数据进行了预处理，然后我们从横向（本届世博对上海的影响）和纵向（本届世博和历届世博的影响比较）两个角度对世博影响力进行了研究，最后还应用了多目标优化模型求出在不同投资增长系数下上海世博对当地旅游经济最大影响力系数。

第一步，我们横向考虑世博会对本地旅游业的影响力，并将该影响分为对旅游经济的影响和对旅游文化的影响两方面。

首先应用本底趋势线模型得出相应数据的本底值，再分别建立对旅游经济和旅游文化的影响力系数模型，然后利用本底值和统计值得出相应的影响力系数，结果表示如下：举办世博影不举办世博影增加的影旅游业时间响力系数响力系数响力系数世博前期 1.18 1 0.18 世博期间 1.58 1 0.58 旅游经济世博后期1.15 1 0.15 世博影响年均值 1.30 1 0.30 旅游文化 1.29 1 0.29 可得出世博期间的世博会对旅游经济影响力系数最大，为1.58。

相比旅游收入的本底值增加了579.39亿元的旅游收入。

而世博对旅游文化的影响力系数为1.29。

第二步，我们纵向考虑上海世博会与历届世博会相比的影响力。

根据收集的历届世博会相关的规模数据，将世博会影响力等级从低到高分为1-5等，从而建立了世博会综合影响力的模糊评价模型。

对历届世博会的影响力做出综合评价并得出了相应的综合影响力系数。

得出的前三名的排名情况如下：举办年份世博会名称综合影响力系数影响力排名2021 上海世博会 4.094134 1 1970 日本万国博览会 3.789834 2 1939 纽约世界博览会3.465383 3 第三步，我们从环保，旅游收入以及后世博效应三个角度对上海世博的影响重新进行了思考。

综合权衡这三个方面因素，我们建立了一个多目标优化的模型。

2016年美国大学生数学建模竞赛C题H奖论文

Contents1.Introduction (1)1.1 Background (1)1.2 Foundation & ROI (1)2 Task (1)3 Fundamental assumptions (2)4 Definitions and Notations (2)5 Models (3)5.1 Filter data (3)5.2 Object Selection Model (Grey Relational Analysis) (4)5.2.1 Model analysis (4)5.2.2 Model solution (4)5.3 ROI Model (Principal Component Analysis) (5)5.3.1 Model analysis (5)5.3.2 Model solution (6)5.4 Verify the possibility (9)5.4.1 Comparison (9)5.4.2 External factor (10)5.5 Investment Forecast Model (11)5.5.1 Linear Regression Forecasting Model (11)5.5.2 School potential Prediction (TOPSIS) (12)5.5.3 Final investment (TOPSIS) (13)6 Conclusions (16)7 Strengths and Weaknesses (18)7.1 Strengths (19)7.2 Weaknesses (20)8 Letter to Mr. Alpha Chiang (21)9 References (22)Team # 44952 Page 1 of 221 Introduction1.1 BackgroundThe Goodgrant Foundation is a charitable organization that wants to help improve educational performance of undergraduates attending colleges and universities in the United States. To do this, the foundation intends to donate a total of $100,000,000 (US100 million) to an appropriate group of schools per year, for five years, starting July 2016. In doing so, they do not want to duplicate the investments and focus of other large grant organizations such as the Gates Foundation and Lumina Foundation.Our team has been asked by the Goodgrant Foundation to develop a model to determine an optimal investment strategy that identifies the schools, the investment amount per school, the return on that investment, and the time duration that the organi zation’s money should be provided to have the highest likelihood of producing a strong positive effect on student performance. This strategy should contain a 1 to N optimized and prioritized candidate list of schools you are recommending for investment bas ed on each candidate school’s demonstrated potential for effective use of private funding, and an estimated return on investment (ROI) defined in a manner appropriate for a charitable organization such as the Goodgrant Foundation.1.2 Foundation & ROIFoundation (charitable foundation) refers to the nonprofit legal person who uses the property of the natural persons, legal persons or other organizations to engage in public welfare undertakings. In terms of its nature, foundation is a kind of folk non-profit organizations.ROI is a performance measure used to evaluate the efficiency of an investment or to compare the efficiency of a number of different investments. ROI measures the amount of return on an investment relative to the investment’s cost. To calculate ROI, the benefit (or return) of an investment is divided by the cost of the investment, and the result is expressed as a percentage or a ratio.2 Task●One-page summary for our MCM submission●Using our models to achieve the candidate list of schools●Calculate the time durati on that the organization’s money should be provided to have thehighest likelihood of producing a strong positive effect on student performance●Calculate the investment amount Goodgrant Foundation would pay for each school●Calculate the ROI of the Goodgrant Foundation●Forecast the development of this kind of investment mode●Write a letter to the CFO of the Goodgrant Foundation, Mr. Alpha Chiang, that describesthe optimal investment strategy。

2010 美赛 MCM 优秀论文

For the second problem, using Rayleigh distribution function, we obtain a preliminary probability distribution of the crime site based on the residence determined in the ﬁrst problem . Taking geographical character and the offender’s geographical preference into account, we utilize cluster analysis to divide all the crime sites into 4 zones. In these 4 zones, we construct 4 two-dimensional normal distributions around the 4 circle centers with the standard deviations being the radii of the circles. In view of the inﬂuence of the crime time, we add a time factor to the preliminary distribution. As a result, the preliminary distribution is modulated by geographical and temporal factors, producing an ultimate prediction, which is rather satisfactory after validation.
3 Center of Minimum Distance Model.................................. 5

2007美国大学生数学建模竞赛B题特等奖论文

American Airlines' Next Top ModelSara J. BeckSpencer D. K'BurgAlex B. TwistUniversity of Puget SoundTacoma, WAAdvisor: Michael Z. SpiveySummaryWe design a simulation that replicates the behavior of passengers boarding airplanes of different sizes according to procedures currently implemented, as well as a plan not currently in use. Variables in our model are deterministic or stochastic and include walking time, stowage time, and seating time. Boarding delays are measured as the sum of these variables. We physically model and observe common interactions to accurately reflect boarding time.We run 500 simulations for various combinations of airplane sizes and boarding plans. We analyze the sensitivity of each boarding algorithm, as well as the passenger movement algorithm, for a wide range of plane sizes and configurations. We use the simulation results to compare the effectiveness of the boarding plans. We find that for all plane sizes, the novel boarding plan Roller Coaster is the most efficient. The Roller Coaster algorithm essentially modifies the outside-in boarding method. The passengers line up before they board the plane and then board the plane by letter group. This allows most interferences to be avoided. It loads a small plane 67% faster than the next best option, a midsize plane 37% faster than the next best option, and a large plane 35% faster than the next best option.IntroductionThe objectives in our study are:To board (and deboard) various sizes of plane as quickly as possible."* To find a boarding plan that is both efficient (fast) and simple for the passengers.With this in mind:"* We investigate the time for a passenger to stow their luggage and clear the aisle."* We investigate the time for a passenger to clear the aisle when another passenger is seated between them and their seat.* We review the current boarding techniques used by airlines.* We study the floor layout of planes of three different sizes to compare any difference between the efficiency of a given boarding plan as plane size increases and layouts vary."* We construct a simulator that mimics typical passenger behavior during the boarding processes under different techniques."* We realize that there is not very much time savings possible in deboarding while maintaining customer satisfaction."* We calculate the time elapsed for a given plane to load under a given boarding plan by tracking and penalizing the different types of interferences that occur during the simulations."* As an alternative to the boarding techniques currently employed, we suggest an alternative plan andassess it using our simulator."* We make recommendations regarding the algorithms that proved most efficient for small, midsize, and large planes.Interferences and Delays for BoardingThere are two basic causes for interference-someone blocking a passenger,in an aisle and someone blocking a passenger in a row. Aisle interference is caused when the passenger ahead of you has stopped moving and is preventing you from continuing down the aisle towards the row with your seat. Row interference is caused when you have reached the correct row but already-seated passengers between the aisle and your seat are preventing you from immediately taking your seat. A major cause of aisle interference is a passenger experiencing rowinterference.We conducted experiments, using lined-up rows of chairs to simulate rows in an airplane and a team member with outstretched arms to act as an overhead compartment, to estimate parameters for the delays cause by these actions. The times that we found through our experimentation are given in Table 1.We use these times in our simulation to model the speed at which a plane can be boarded. We model separately the delays caused by aisle interference and row interference. Both are simulated using a mixed distribution definedas follows:Y = min{2, X},where X is a normally distributed random variable whose mean and standard deviation are fixed in our experiments. We opt for the distribution being partially normal with a minimum of 2 after reasoning that other alternative and common distributions (such as the exponential) are too prone to throw a small value, which is unrealistic. We find that the average row interference time is approximately 4 s with a standard deviation of 2 s, while the average aisle interference time is approximately 7 s with a standard deviation of 4 s. These values are slightly adjusted based on our team's cumulative experience on airplanes.Typical Plane ConfigurationsEssential to our model are industry standards regarding common layouts of passenger aircraft of varied sizes. We use an Airbus 320 plane to model a small plane (85-210 passengers) and the Boeing 747 for a midsize plane (210-330 passengers). Because of the lack of large planes available on the market, we modify the Boeing 747 by eliminating the first-class section and extending the coach section to fill the entire plane. This puts the Boeing 747 close to its maximum capacity. This modified Boeing 747 has 55 rows, all with the same dimensions as the coach section in the standard Boeing 747. Airbus is in the process of designing planes that can hold up to 800 passengers. The Airbus A380 is a double-decker with occupancy of 555 people in three different classes; but we exclude double-decker models from our simulation because it is the larger, bottom deck that is the limiting factor, not the smaller upper deck.Current Boarding TechniquesWe examine the following industry boarding procedures:* random-order* outside-in* back-to-front (for several group sizes)Additionally, we explore this innovative technique not currently used by airlines:* "Roller Coaster" boarding: Passengers are put in order before they board the plane in a style much like those used by theme parks in filling roller coasters.Passengers are ordered from back of the plane to front, and they board in seatletter groups. This is a modified outside-in technique, the difference being that passengers in the same group are ordered before boarding. Figure 1 shows how this ordering could take place. By doing this, most interferencesare avoided.Current Deboarding TechniquesPlanes are currently deboarded in an aisle-to-window and front-to-back order. This deboarding method comes out of the passengers' desire to be off the plane as quickly as possible. Any modification of this technique could leadto customer dissatisfaction, since passengers may be forced to wait while others seated behind them on theplane are deboarding.Boarding SimulationWe search for the optimal boarding technique by designing a simulation that models the boarding process and running the simulation under different plane configurations and sizes along with different boarding algorithms. We then compare which algorithms yielded the most efficient boarding process.AssumptionsThe environment within a plane during the boarding process is far too unpredictable to be modeled accurately. To make our model more tractable,we make the following simplifying assumptions:"* There is no first-class or special-needs seating. Because the standard industry practice is to board these passengers first, and because they generally make up a small portion of the overall plane capacity, any changes in the overall boarding technique will not apply to these passengers."* All passengers board when their boarding group is called. No passengers arrive late or try to board the plane early."* Passengers do not pass each other in the aisles; the aisles are too narrow."* There are no gaps between boarding groups. Airline staff call a new boarding group before the previous boarding group has finished boarding the plane."* Passengers do not travel in groups. Often, airlines allow passengers boarding with groups, especially with younger children, to board in a manner convenient for them rather than in accordance with the boarding plan. These events are too unpredictable to model precisely."* The plane is full. A full plane would typically cause the most passenger interferences, allowing us to view the worst-case scenario in our model."* Every row contains the same number of seats. In reality, the number of seats in a row varies due to engineering reasons or to accommodate luxury-class passengers.ImplementationWe formulate the boarding process as follows:"* The layout of a plane is represented by a matrix, with the rows representing rows of seats, and each column describing whether a row is next to the window, aisle, etc. The specific dimensions vary with each plane type. Integer parameters track which columns are aisles."* The line of passengers waiting to board is represented by an ordered array of integers that shrinks appropriately as they board the plane."* The boarding technique is modeled in a matrix identical in size to the matrix representing the layout of the plane. This matrix is full of positive integers, one for each passenger, assigned to a specific submatrix, representing each passenger's boarding group location. Within each of these submatrices, seating is assigned randomly torepresent the random order in which passengers line up when their boarding groups are called."* Interferences are counted in every location where they occur within the matrix representing the plane layout. These interferences are then cast into our probability distribution defined above, which gives ameasurement of time delay."* Passengers wait for interferences around them before moving closer to their assigned seats; if an interference is found, the passenger will wait until the time delay has finished counting down to 0."* The simulation ends when all delays caused by interferences have counted down to 0 and all passengers have taken their assigned seats.Strengths and Weaknesses of the ModelStrengths"* It is robust for all plane configurations and sizes. The boarding algorithms that we design can be implemented on a wide variety of planes with minimal effort. Furthermore, the model yields reasonable results as we adjust theparameters of the plane; for example, larger planes require more time to board, while planes with more aisles can load more quickly than similarlysized planes with fewer aisles."* It allows for reasonable amounts of variance in passenger behavior. While with more thorough experimentation a superior stochastic distribution describing the delays associated with interferences could be found, our simulationcan be readily altered to incorporate such advances."* It is simple. We made an effort to minimize the complexity of our simulation, allowing us to run more simulations during a greater time period and mini mizing the risk of exceptions and errors occurring."* It is fairly realistic. Watching the model execute, we can observe passengers boarding the plane, bumping into each other, taking time to load their baggage, and waiting around as passengers in front of them move out of theway. Its ability to incorporate such complex behavior and reduce it are key to completing our objective. Weaknesses"* It does not account for passengers other than economy-class passengers."* It cannot simulate structural differences in the boarding gates which couldpossibly speed up the boarding process. For instance, some airlines in Europeboard planes from two different entrances at once."* It cannot account for people being late to the boarding gate."* It does not account for passenger preferences or satisfaction.Results and Data AnalysisFor each plane layout and boarding algorithm, we ran 500 boarding simulations,calculating mean time and standard deviation. The latter is important because the reliability of plane loading is important for scheduling flights.We simulated the back-to-front method for several possible group sizes.Because of the difference in thenumber of rows in the planes, not all group size possibilities could be implemented on all planes.Small PlaneFor the small plane, Figure 2 shows that all boarding techniques except for the Roller Coaster slowed the boarding process compared to the random boarding process. As more and more structure is added to the boarding process, while passenger seat assignments continue to be random within each of the boarding groups, passenger interference backs up more and more. When passengers board randomly, gaps are created between passengers as some move to the back while others seat themselves immediately upon entering the plane, preventing any more from stepping off of the gate and onto the plane. These gaps prevent passengers who board early and must travel to the back of the plane from causing interference with many passengers behind them. However, when we implement the Roller Coaster algorithm, seat interference is eliminated, with the only passenger causing aisle interference being the very last one to boardfrom each group.Interestingly, the small plane's boarding times for all algorithms are greater than their respective boarding time for the midsize plane! This is because the number of seats per row per aisle is greater in the small plane than in the midsize plane.Midsize PlaneThe results experienced from the simulations of the mid-sized plane areshown in Figure 3 and are comparable to those experienced by the small plane.Again, the Roller Coaster method proved the most effective.Large PlaneFigure 4 shows that the boarding time for a large aircraft, unlike the other plane configurations, drops off when moving from the random boarding algorithm to the outside-in boarding algorithm. Observing the movements by the passengers in the simulation, it is clear that because of the greater number of passengers in this plane, gaps are more likely to form between passengers in the aisles, allowing passengers to move unimpeded by those already on board.However, both instances of back-to-front boarding created too much structure to allow these gaps to form again. Again, because of the elimination of row interference it provides for, Roller Coaster proved to be the most effective boarding method.OverallThe Roller Coaster boarding algorithm is the fastest algorithm for any plane pared to the next fastest boarding procedure, it is 35% faster for a large plane, 37% faster for a midsize plane, and 67% faster for a small plane. The Roller Coaster boarding procedure also has the added benefit of very low standard deviation, thus allowing airlines a more reliable boarding time. The boarding time for the back-to-front algorithms increases with the number of boarding groups and is always slower than a random boarding procedure.The idea behind a back-to-front boarding algorithm is that interference at the front of the plane is avoided until passengers in the back sections are already on the plane. A flaw in this procedure is that having everyone line up in the plane can cause a bottleneck that actually increases the loading time. The outside-in ("Wilma," or window, middle, aisle) algorithm performs better than the random boarding procedure only for the large plane. The benefit of the random procedure is that it evenly distributes interferences throughout theplane, so that they are less likely to impact very many passengers.Validation and Sensitivity AnalysisWe developed a test plane configuration with the sole purpose of implementing our boarding algorithms on planes of all sizes, varying from 24 to 600 passengers with both one or two aisles.We also examined capacities as low as 70%; the trends that we see at full capacity are reflected at these lower capacities. The back-to-front and outside-in algorithms do start to perform better; but this increase inperformance is relatively small, and the Roller Coaster algorithm still substantially outperforms them. Underall circumstances, the algorithms we test are robust. That is, they assign passenger to seats in accordance with the intention of the boarding plans used by airlines and move passengers in a realistic manner.RecommendationsWe recommend that the Roller Coaster boarding plan be implemented for planes of all sizes and configurations for boarding non-luxury-class and nonspecial needs passengers. As planes increase in size, its margin of success in comparison to the next best method decreases; but we are confident that the Roller Coaster method will prove robust. We recommend boarding groups that are traveling together before boarding the rest of the plane, as such groups would cause interferences that slow the boarding. Ideally, such groups would be ordered before boarding.Future WorkIt is inevitable that some passengers will arrive late and not board the plane at their scheduled time. Additionally, we believe that the amount of carry-on baggage permitted would have a larger effect on the boarding time than the specific boarding plan implemented-modeling this would prove insightful.We also recommend modifying the simulation to reflect groups of people traveling (and boarding) together; this is especially important to the Roller Coaster boarding procedure, and why we recommend boarding groups before boarding the rest of the plane.。

建模美赛获奖范文

建模美赛获奖范文全文共四篇示例，供读者参考第一篇示例：近日，我校数学建模团队在全国大学生数学建模竞赛中荣获一等奖的喜讯传来，这是我校首次在该比赛中获得如此优异的成绩。

本文将从建模过程、团队合作、参赛经验等方面进行详细介绍，希望能为更多热爱数学建模的同学提供一些借鉴和参考。

让我们来了解一下比赛的背景和要求。

全国大学生数学建模竞赛是由中国工程院主办，旨在促进大学生对数学建模的兴趣和掌握数学建模的基本方法和技巧。

比赛通常会设置一些实际问题，参赛队伍需要在规定时间内通过建立数学模型、分析问题、提出解决方案等步骤来完成任务。

最终评选出的优胜队伍将获得一等奖、二等奖等不同级别的奖项。

在本次比赛中，我们团队选择了一道关于城市交通拥堵研究的题目，并从交通流理论、路网优化等角度进行建模和分析。

通过对城市交通流量、拥堵原因、路段限制等方面的研究，我们提出了一种基于智能交通系统的解决方案，有效缓解了城市交通拥堵问题。

在展示环节，我们通过图表、数据分析等方式清晰地呈现了我们的建模过程和成果，最终赢得了评委的认可。

在整个建模过程中，团队合作起着至关重要的作用。

每个成员都发挥了自己的专长和优势，在分析问题、建模求解、撰写报告等方面各司其职。

团队内部的沟通和协作非常顺畅，大家都能积极提出自己的想法和看法，达成共识后再进行实际操作。

通过团队合作，我们不仅完成了比赛的任务，也培养了团队精神和合作能力，这对我们日后的学习和工作都具有重要意义。

参加数学建模竞赛是一次非常宝贵的经历，不仅能提升自己的数学建模能力，也能锻炼自己的解决问题的能力和团队协作能力。

在比赛的过程中，我们学会了如何快速建立数学模型、如何分析和解决实际问题、如何展示自己的成果等，这些能力对我们未来的学习和工作都将大有裨益。

在未来，我们将继续努力，在数学建模领域不断学习和提升自己的能力，为更多的实际问题提供有效的数学解决方案。

我们也希望通过自己的经验和教训，为更多热爱数学建模的同学提供一些指导和帮助，共同进步，共同成长。

2015美国大学生数学建模竞赛一等奖论文

2015 Mathematical Contest in Modeling (MCM) Summary Sheet
Summary
In this paper ,we not only analyze the spread of Ebola, the quantity of the medicine needed, the speed of manufacturing of the vaccine or drug, but also the possible feasible delivery systems and the optimal locations of delivery. Firstly, we analyze the spread of Ebola by using the linear fitting model, and obtain that the trend of development of Ebola increases rapidly before the medicine is used. And then, we build susceptible-infective-removal (SIR) model to predict the trend after the medicine is used, and find that the ratio of patients will decrease. Secondly, we investigate that the quantity of patients equals the quantity of the medicine needed. Via SIR model, the demand of medicine can be calculated and the speed of manufacturing of the vaccine or drug can be gotten by using Calculus (Newton.1671). Thirdly, as for the study of locations of delivery and delivery system, in Guinea, Liberia, and Sierra Leone, we establish the Network graph model and design a kind of arithmetic. Through attaching weights to different points, solving the problem of shortest distance, and taking the optimization mathematical model into consideration, we acquire four optimal locations and the feasible delivery systems on the map. Finally, we consider the other critical factors which may affect the spread of Ebola, such as production capacity, climate, vehicle and terrain, and analyze the extent of every factor. We also analyze the sensitivity of model and give the method that using negative feedback system to improve the accuracy of our models. In addition, we explore our models to apply to other fields such as the H1N1 and the earthquake of Sichuan in China. Via previous analysis, we can predict spread of Ebola and demand of medicine, get the optimal locations. Besides, our model can be applied to many fields.

2013年美国大学生数学建模大赛B题获奖论文

For office use onlyT1________________ T2________________ T3________________ T4________________Team Control Number22599Problem ChosenAFor office use onlyF1________________F2________________F3________________F4________________ 2013Mathematical Contest in Modeling(MCM/ICM)Summary Sheet(Attach a copy of this page to your solution paper.)Heat Radiation in The OvenHeat distribution of pans in the oven is quite different from each other,which depends on their shapes.Thus,our model aims at two goals.One is to analyze the heat distri-bution in different ovens based on the locations of electrical heating cubes.Further-more,a series of heat distribution which varies from circular pans to rectangular pans could be got easily.The other is to optimize the pans placing,in order to choose a best way to maximize the even heat and the number of pans at the same time.Mathematically speaking,our solution consists of two models,analyzing and optimi-zing.In part one,our whole-local approach shows the heat distribution of every pan.Firstly,we use the Stefan-Boltzmann law and Fourier theorem to describe the heat distribution in the air around the electrical heating tube.And then, based on plane in-tercept method and simplified Monte Carlo method,the heat distribution of different shapes of pans is obtained.Finally,we explain the phenomenon that the corners of a pan always get over heated with water waves stirring by analogy.In part two,our discretize-convert approach optimizes the shape and number of the pans.Above all,we discre-tize the side length of the oven, so that the number and the average heat of the pans vary linearly.In the end,the abstract weight P is converted into a specific length,in order to reach a compromise between the two factors.Specially,we create a unique method to convert the variables from the whole space to the local section.The special method allows us to draw the heat distribution of every single section in the oven.The algorithm we create does a great job in flexibility,which can be applied to all shapes of pans.Type a summary of your results on this page.Do not includethe name of your school,advisor,or team members on this page.Heat Radiation in The OvenSummaryHeat distribution of pans in the oven is quite different from each other,which depends on their shapes.Thus,our model aims at two goals.One is to analyze the heat distri-bution in different ovens based on the locations of electrical heating cubes.Further-more,a series of heat distribution which varies from circular pans to rectangular pans could be got easily.The other is to optimize the pans placing,in order to choose a best way to maximize the even heat and the number of pans at the same time.Mathematically speaking,our solution consists of two models,analyzing and optimi-zing.In part one,our whole-local approach shows the heat distribution of every pan. Firstly,we use the Stefan-Boltzmann law and Fourier theorem to describe the heat distribution in the air around the electrical heating tube.And then,based on plane in-tercept method and simplified Monte Carlo method,the heat distribution of different shapes of pans is obtained.Finally,we explain the phenomenon that the corners of a pan always get over heated with water waves stirring by analogy.In part two,our discretize-convert approach optimizes the shape and number of the pans.Above all, we discre-tize the side length of the oven,so that the number and the average heat of the pans vary linearly.In the end,the abstract weight P is converted into a specific length,in order to reach a compromise between the two factors.Specially,we create a unique method to convert the variables from the whole space to the local section.The special method allows us to draw the heat distribution of every single section in the oven.The algorithm we create does a great job in flexibility, which can be applied to all shapes of pans.Keywords:Monte Carlo thermal radiation section heat distribution discretizationIntroductionMany studies on heat conduction wasted plenty of time in solving the partial differential equations,since it’s difficult to solve even for computers.We turn to another way to work it out.Firstly,we study the heat radiation instead of heat conduction to keep away from the sophisticated partial differential equations.Then, we create a unique method to convert every variable from the whole space to section. In other words,we work everything out in heat radiation and convert them into heat contradiction.AssumptionsWe make the following assumptions about the distribution of heat in this paper.·Initially two racks in the oven,evenly spaced.·When heating the electrical heating tubes,the temperature of which changes from room temperature to the desired temperature.It takes such a short time that we can ignore it.·Different pans are made in same material,so they have the same rate of heat conduction.·The inner walls of the oven are blackbodies.The pan is a gray body.The inner walls of the oven absorb heat only and reflect no heat.·The heat can only be reflected once when rebounded from the pan.Heat Distribution ModelOur approach involves four steps:·Use the Fourier theorem to calculate the loss energy when energy beams are spread in the medium.So we can get the heat distribution around each electrical heating tube.The heat distribution of the entire space could be go where the heat of two electrical heating tubes cross together.·When different shapes of the pans are inserted into the oven,the heat map of the entire space is crossed by the section of the pan.Thus,the heat map of every single pan is obtained.·Establish a suitable model to get the reflectivity of every single point on the pan with the simplified Monte Carlo method.And then,a final heat distribution map of the pan without reflection loss is obtained.·A realistic conclusion is drawn due to the results of our model compared with water wave propagation phenomena.First of all,the paper will give a description of the initial energy of the electrical hea-ting tube.We see it as a blackbody who reflects no heat at all.Electromagnetic know-ledge shows that wavelength of the heat rays ranges from um 110−to um 210as shown below[1]:Figure 1.Figure 2.We apply the Stefan-Boltzmann’s law[2]whose solution is ()1/512−=−T c b e c E λλλ(1)()λλλλλd e c d E E T c b b ∫∫∞−∞−==0/51012(2)Where b E means the ability of blackbody to radiate. 1c and 2c are constants.Obviously,,the initial energy of a black body is )(0122398.320m w e E b ×+=.Combine Figure 1with Figure 2,we integrate (1)from 1λto 2λto get the equation as follow:λλλλλλd E E b b ∫=−2121)((3)Figure 3.From Figure 3,it can be seen how the power of radiation varies with wavelength.Secondly,based on the Fourier theorem,the relation between heat and the distance from the electrical heating tubes is:dxdt S Q λ−=(4)Where Q is the power of heat (W s J =/),S is the area where the energy beamradiates (2m ),dxdt represents the temperature gradient along the direction of energy beam.[3]It is known that the energy becomes weaker as the distance becomes larger.According to the fact we know:dxdQ =ρ(5)Where ρis the rate of energy changing.We assume that the desired temperature of electrical heating tube is 500k.With the two equations,the distribution of heat is shown as follow:Figure 4.(a)Figure 4.(b)In order to draw the map of heat distribution in the oven,we use MATLAB to work on the complicated algorithm.The relation between the power of heat and the distance is shown in Figure4(a).The relation between temperature and distance is presented in Figure4(b).The spreading direction of energy beam is presented in Figure5.Figure5.The shape of electrical heating tube is irregular.The heat distribution of a single electrical heating tube can be draw in3D space with MATLAB.The picture is shown in Figure6.After superimposing,the total heat distribution of two tubes is shown below in Figure7and Figure8.Figure6.Figure7.Figure8.The pictures above show the energy in an oven with no pan.We put in a rectangular pan whose area is A,and intercept the maps with MATLAB.The result is show in Figure9.Figure9.Figure10.Put in a circular pan to intercept the maps,whose area is A,also.The distribution of heat is shown in Figure11.Figure11.When put in a pan in transition shape,which is neither rectangular nor circular.The area of it is A,also.The heat distribution on such a pan is shown as follow:Figure12(a)Figure12(b).Figure13.Next,learning from the Monte Carlo simulation[4],a model is established to get obtain the reflectivity.We generate a random number between0and1to determine if the energy beam on certain point is reflected.•Firstly,to demonstrate the question better,we construct a simple model:Figure 14.Where θis the viewing angle from electrical heating tube to the pan.360θ=R is the proportion of the beams radiated to the pan.•What is more,we assume the total beam is 1M .Ideally,the number of absorption is3601θ×M .Then,each element of the pan is seen as a grid point.Each grid point can generate a-3601θ×M -random-number vector between 0and 1in MATLAB.•After MATLAB simulating,the number of beams decreased by 2M ,due to thereflection.So we define a probability θρ12360M M ×=to describe the number of beams reflected.The conclusion is :•If R ≤ρ,the energy beam is absorbed.•If R >ρ,the energy beam is reflected.[5]Based on the analysis above,our model get a final result of heat-distribution on the pan as shown below:Figure 15(a)Figure15(b).The conclusion is known that the closer the shape of pans is to circle,the more evenly the heat is distributed.Moreover,the phenomenon that the corners always get over heated can be explained by water wave propagation in different containers.When there is a fluctuation in the center of the water,the ripples will fluctuate and spread in concentric circles,as shown in Figure16.The fluctuation stirs waves up when contacting the pared with the waves with one boundary,the waves in corner make a higher amplitude.The thermal conduction on the pan is exactly the inverse process of the waves propagation.The range of thermal motion is much smaller than it on the side.That’s why the corners is easy to get over heated.In order to make the heat evenly distributed on the pan,the sides of the pan should be as few as possible.Therefore,if nothing is considered about the utilization of space,a circle pan is the best choice.Figure16,the water waves propagation[6]According to the analysis above and Figure7,the phenomenon shows that the heat conduction is similar to water waves propagation.So it is proved that heatconcentrates in the four corners of the rectangular pan.The Super Pan ModelAssumptions•The width of the oven(W)is mm100,the length is L.•There are three pans at most in vertical direction.•Each pan’s area is A.The first part.Calculate the maximum number of pans in the oven.Different shapes of pan have different heat distribution which affects the number of pans,judging from the previous solution.According to the conclusion in the first model,the heat is distributed the most evenly on a circular pan rather than a rectangular one.However, the rectangular pans make fuller use of the space the space than circular ones.Both factors considered,a polygonal pan is chosen.A circle can be regard as a polygon whose number of boundaries tends to infinity. Except for rectangle,only regular hexagon and equilateral triangle can be closely placed.Because of the edges of equilateral triangle,heat dissipation is worse than rectangle.So,hexagonal pans are adopted after all the discussion.Considering the gaps near boundaries,we place the hexagonal pans closely attached each other on the long side L.There are two kinds of programs as shown below.Program1.Program2.Obviously,Program2is better than Program1when considering space utilization.So scheme 1is adopted.Then,design a size of each hexagonal pan to make the highest space utilization.With the aim of utilization,hexagonal pans has to be placed contact closely with each other on both sides.It is necessary to assume a aspect ratio of the oven to work out the number of pans(N ).Assume that the side length of a regular hexagon is a ,the length-width ratio of the oven is λand L ∆is the increment in discretization.Because the number of pans can not change continuously when ⋅⋅⋅=+∈3,2,1),1,(m m m n ,the equations would be as follows.⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎧⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡⋅−====∆⋅+<⎥⎦⎤⎢⎣⎡∆⋅+−∆⋅+≤⋅=∆∆⋅+=<<=a W L n W L N Lk L W W L k L W L k L a L L k L L L W aW 23,810;23105000λ(6)Result:⎪⎪⎩⎪⎪⎨⎧⋅⋅⋅==⋅+=⋅⋅⋅=−=+−⋅+=3,2,1,2233,2,1,1212130201k k n n N N k k n n N N Where 1N represents the number of pans when n is odd,2N represents the number of pans when n is even.The specific number of pans is depended on the width-length ratio of oven.The second part.Maximum the heat distribution of the pans.We define the average heat(H )as the ratio of total heat and total area of the pans.Aiming to get the most average heat,we set the width-length ratio of the oven λ.Space utilization is not considered here.A conclusion is easy to draw from Figure 8that a square area in the oven from 150mm to 350mm in length shares the most heat evenly.So the pans should beplaced mainly in this area.From model1we know that the corners of the oven are apt to gather heat.Besides,four more pans are added in the corners to absorb more heat. Because heat absorbing is the only aim,there is no need to consider space utilization. Circular pans can distribute heat more evenly than any other shape due to model1.So circular pans are used in Figure17.Figure8.Figure17.We set the heat of the pans in the most heated area(the middle row)as Q.Pans in the corners receive more heat but uneven theoretically.And the square of the four pans in the corners is so small compared with the total square that we set the heat of the four as Q too.When the length of oven(L)increases,the number of pans increases too. It makes the square of the gaps between pans bigger,meanwhile.If each pan has a same radius(r)and square(A),the equation about average heat,length-width ratio and number of pans would be(7).⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎧=+=⎥⎦⎤⎢⎣⎡⋅−====∆⋅+<⎦⎤⎢⎣⎡∆⋅+−∆⋅+≤⋅=∆∆⋅+=<<⋅=⋅⋅=...3,2,12;71021053410002k nN N r W L n W L N L k L W W L k L W L k L r L L k L L L W r A W r λπ(7)Here we get the most average heat (H ):29400WQ H ⋅=πThe third part.We discussed two different plans in the previous parts of the paper.One is aimed to get the most average heat,while the other aimed to place the most pans.The two plans are contradictory with each other,and can not be achieved together.Firstly,the weight of plan 1is P and the weight of plan 2is P −1.Obviously,this kind optimization has difficulty in solving and understanding.So we turn to another way to make it a easier and linear question.It has been set that the width of the oven is a constant W and there should be three pans at most in vertical direction.We make the weight P a proportion of the two plans.Thus the two plans could be achieved together due to proportion P and P −1,as shown in Figure18.Figure 18.As been told in model 1,the corners have a higher temperature than other parts of the oven.So plan 1is used in district 1(in Figure 10)and plan 2is used in district 2(in Figure 10).A better compromise could be reached in this way,as shown in Figure 19.Figure 19.Every pan has a square of A .Radius of circular ones is r .Side length of regular hexagon is a .1.1:23322=⇒⋅=⋅r a a r π(8)Based on the equation (8),if the pans are placed as shown in Figure 19,regular hexagons are placed full of district 1,the circular ones will be placed beyond the border line.If the circular ones are placed full of district 2,there will be more gaps in district 1,which will be wasted.So we change our plan of placing pans as Figure 20.Figure 20.The number of circular ones decreases by two,but the space in district 1is fully used,and no pan will be placed beyond the borderline.We assume that P is bigger than P −1,so that,the heat in district 1will be fully used.By simple calculating,we know that the ratio of the heat absorbed in circular pan (1H )and in regular hexagon (2H )is 1.2:1.Figure21.So,based on the pans placing plan,a equation on heat can be got as follow:⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎧=⎥⎦⎤⎢⎣⎡−⋅−=⎥⎦⎤⎢⎣⎡−⋅====∆⋅+<⎥⎦⎤⎢⎣⎡∆⋅+−∆⋅+≤=∆∆⋅+=<<⋅=⋅==≈...3,2,1)1(,911233;23212kxWLPnxWLPnWLNLkLWWLkLWLkLxLLkLLLWraAxraλπ(9)Resolution:⎪⎪⎪⎪⎪⎪⎪⎩⎪⎪⎪⎪⎪⎪⎪⎨⎧=⋅⋅+⋅+⋅⋅+=⋅⋅+⋅+⋅⋅−+==⋅+⋅+=−=+−⋅+⋅+=...3,2,1)24(2.1)325()24(2.1)3215()2(232)12(12132221212111121211201k A N n Q Q n H A N n Q Q n H k n n n N N k n n n N N (10)1N and 1H means the number of pans and average heat absorbed when n is odd.2N and 2H means the number of pans and average heat absorbed when n is even.For example:(1)When 37.0=λ,6.0=P :16=N ,AQ H 075.1=.The best placing plan is:(2)When 37.0=λ,7.0=P :18=N ,AQ H ⋅=044.1.The best placing planis:(3)When 58.0=λ,6.0=P ：12=N ,AQ H ⋅=067.1.The best placing plan is:A conclusion is easy to draw that when the ratio of width and length of the oven (λ)is a constant,the number of pans increases with an increasing P,but the average heat decreases (example (1)and (2)).When the weight P is a constant,the number of pans decreases with an increasing λ,and the average heat decreases also.So,the actual plan should be base on your specific needs.ConclusionIn conclusion,our team is very certain that the method we came up with is effective in heat distribution analysis.Based on our model,the more edges the pan has,the more evenly the heat distribute on.With the discretize-convert approach,we know that when the ratio of width and length of the oven (γ)is a constant,the number of pans increases with an increasing P ,but the average heat decreases.When the weight P is a constant,the number of pans decreases with an increasing γ,and the average heat decreases also.So,the actual plan should be base on your specific needs.Strengths &WeaknessesStrengths•Difficulties Avoided Avoided..In model 1,we turn to another way to work simulate the heat distribution instead of work on heat conduction directly.Firstly,we simulate heat radiation not heat conduction to keep away from the sophisticated partial differential equations.Then,we create a unique method to convert every variable from the whole space to section.In other words,we work everything out in heat radiation and convert them into heat contradiction.•Close to Reality.Our model considers both the thermal radiation and surface reflection,which is relatively close to the actual situation.•Flexibility Provided.Our algorithm does a great job in flexibility.The heat distribution map on sections are intercepted from the heat distribution maps of the entire space.All shapes of sections can be used in the algorithm.The heat distribution in the whole space is generated based on the location of the electrical heating tubes and the decay curve of the heat, which can be modified at any time.•Innovation.Based on our model,the space of an oven can be divided into six parts with different hear distribution.In order to make full use of the inner space,we invent a new pan which allows users to cook six different kinds of food at same time.An advertisement is published in the end of the paper.WeaknessesPan’’s Thermal Conductivity Ignored.•PanThe heat comes from not only the electrical heating tubes,but also heat conduction of the pans themselves.But the pan’s thermal conduction is ignored in the model,which may cause little inaccuracy.•Thermal Conductivity of Electrical Heating Tubes IgnoredIgnored..it is assumed that there are two electrical heating tubes in the oven and placed in a specific location.The initial temperature of the tubes is a desired constant temperature. In other words,the time electrical heating tubes spend to heating themselves is ignored.The simplification can cause some inaccuracy.simplification..•Linear simplificationIn model2,the length of the oven is discretized,so that the number of pans will changes linearly.calculating through simple integer linear method.This will lead to the result of our model is not accurate enough.ApplicationWe have discussed the heat distribution in the oven in model1.The heat distributionis shown in figure1and figure2.Figure1Figure2As shown,the edges of the oven are distributed the most heat.Areas on both sides of the,is distributed the least heat.While the middle area absorbs little less than theedges.So,we can separate the oven area into six parts,as shown bellow.Part1and part2are distributed the least heat and located the furthest from the heat source(the electrical heating tubes locate on the bottom of the oven).So these two parts absorb the least heat.Part3and part4are distributed the least heat but locating the nearest to the heat source.Part5located far from the bottom but distributed the most heat.So simply,we regard the heat of part3,part4and part5as the same.Part6 is distributed the most heat,and locating nearest to the bottom.So,the heat part6 absorbs is the most in the oven.Based on our conclusion above,we invent the iPan,a new combined pan,which can bake three kinds of food at the same time.For example,one wants to have a little bread,pieces of sausage,a chicken wing and a pizza for lunch.He will have to wait 30minutes at least for his lunch,if he just has one oven.As the Chinese saying goes,‘Bear paws and fish never come together’.By using iPan can solve the issue for him,he could put the bread in pan1,pizza in pan2,sausage in pan5and chicken wing in pan6,and power on.Thus,he can have his delicious lunch in at least10minutes.So,bear paws and fish come together.We make an advertisement for Brownie Gourmet Magazine in the end of the paper.Advertising SheetsReferences[1]Heat Radiation,/view/f5ed1619cc7931b765ce1599.html, Page.4[2]G.S.Ranganath,Black-body Radiation,/article/10.1007%2Fs12045-008-0028-7?LI=true#,February, 2013[3]Kaiqing Lu,The Chemical Basis of Heat Transfer,Journal of Higher Correspondence Education(Natural Sciences Edition),Vol.3:p.33,1996[4]Mark M.Meerschaert,Mathematical Modeling(Third Edition),China:China Machine Press,May.2009[5]Jianzhong Zhang,Monte Carlo Method,Mathematics in Practice and Theory,Vol.1p.28,1974[6]Shallow water equations,/wiki/Shallow_water_equations。

数学建模经典论文五篇

1、血样的分组检验在一个很大的人群中通过血样检验普查某种疾病,假定血样为阳性的先验概率为p(通常p 很小).为减少检验次数,将人群分组,一组人的血样混合在一起化验.当某组的混合血样呈阴性时,即可不经检验就判定该组每个人的血样都为阴性;而当某组的混合血样呈阳性时,则可判定该组至少有一人血样为阳性,于是需要对这组的每个人再作检验.(1)、当p 固定时(如0.01%,…,0.1%,…,1%)如何分组,即多少人一组,可使平均总检验次数最少,与不分组的情况比较. (2)、当p 多大时不应分组检验.(3)、当p 固定时如何进行二次分组(即把混合血样呈阳性的组再分成小组检验,重复一次分组时的程序).模型假设与符号约定1 血样检查到为阳性的则患有某种疾病,血样呈阴性时的情况为正常2 血样检验时仅会出现阴性、阳性两种情况,除此之外无其它情况出现,检验血样的药剂灵敏度很高，不会因为血样组数的增大而受影响. 3 阳性血样与阳性血样混合也为阳性 4 阳性血样与阴性血样混合也为阳性 5 阴性血样与阴性血样混合为阴性 n 人群总数 p 先验概率血样阴性的概率q=1-p血样检验为阳性（患有某种疾病）的人数为:z=np 发生概率:x i P i ,,2,1, = 检查次数:x i R i ,,2,1, = 平均总检验次数:∑==xi i i R P N 1解1设分x 组,每组k 人（n 很大,x 能整除n,k=n/x ）,混合血样检验x 次.阳性组的概率为k q p -=11,分组时是随机的,而且每个组的血样为阳性的机率是均等的,阳性组数的平均值为1xp ,这些组的成员需逐一检验,平均次数为1kxp ,所以平均检验次数1kxp x N +=,一个人的平均检验次数为N/n,记作:k k p kq k k E )1(1111)(--+=-+=(1) 问题是给定p 求k 使E(k)最小. p 很小时利用kp p k -≈-1)1(可得kp kk E +=1)( (2) 显然2/1-=p k 时E(k)最小.因为K 需为整数,所以应取][2/1-=p k 和1][2/1+=-p k ,2当E （k ）>1时,不应分组,即:1)1(11>--+k p k,用数学软件求解得k k p /11-->检查k=2,3,可知当p>0.307不应分组.3将第1次检验的每个阳性组再分y 小组,每小组m 人（y 整除k,m=k/y ）.因为第1次阳性组的平均值为1xp ,所以第2次需分小组平均检验1yxp 次,而阳性小组的概率为m q p -=12（为计算2p 简单起见,将第1次所有阳性组合在一起分小组）,阳性小组总数的平均值为21yp xp ,这些小组需每人检验,平均检验次数为21yp mxp ,所以平均总检验次数211yp mxp yxp x N ++=,一个人的平均检验次数为N/n,记作(注意:n=kx=myx)p q q q mk p p m p k m k E m k -=-+-+=++=1),1()1(111),(211 (3) 问题是给定p 求k,m 使E （k,m ）最小.P 很小时（3）式可简化为21),(kmp mkpk m k E ++≈ (4)对（4）分别对k,m 求导并令其等于零,得方程组:⎪⎪⎩⎪⎪⎨⎧=+-=++-0012222kp m kp mp mp k 舍去负数解可得:2/14/3,21--==p m p k (5)且要求k,m,k/m 均为整数.经在（5）的结果附近计算,比较E(k,m),得到k,m 的最与表1比较可知,二次分组的效果E(k,m)比一次分组的效果E(k)更好.2、铅球掷远问题铅球掷远比赛要求运动员在直径2.135m 的圆内将重7.257kg 的铅球投掷在 45的扇形区域内，建立模型讨论以下问题1．以出手速度、出手角度、出手高度为参数，建立铅球掷远的数学模型；2．考虑运动员推铅球时用力展臂的动作，改进以上模型．3．在此基础上，给定出手高度，对于不同的出手速度，确定最佳出手角度问题1模型的假设与符号约定1 忽略空气阻力对铅球运动的影响．2 出手速度与出手角度是相互独立的．3 不考虑铅球脱手前的整个阶段的运动状态． v 铅球的出手速度 θ 铅球的出手角度 h 铅球的出手高度 t 铅球的运动时间 L 铅球投掷的距离g 地球的重力加速度(2/8.9s m g=)铅球出手后，由于是在一个竖直平面上运动．我们，以铅球出手点的铅垂方向为y 轴，以y 轴与地面的交点到铅球落地点方向为x 轴构造平面直角坐标系．这样，铅球脱手后的运动路径可用平面直角坐标系表示，如图．因为，铅球出手后，只受重力作用（假设中忽略空气阻力的影响），所以，在x 轴上的加速度0=，在y 轴上的加速度g a y -=．如此，从解析几何角度上，以时间 t 为参数，易求得铅球的运动方程：⎪⎩⎪⎨⎧+-==h gt t v y t v x 221sin cos θθ 对方程组消去参数t ，得h x x v gy ++-=)(tan cos 2222θθ……………………………………………(1) 当铅球落地时，即是0=y ，代入方程(1)解出x 的值v ggh gh v g v x θθθθθ2222sin 22cos sin cos sin 2-++=对以上式子化简后得到铅球的掷远模型θθθ22222cos 22sin 222sin g v h g v g v L +⎪⎪⎭⎫ ⎝⎛+=………………………………(2) 问题2我们观察以上两个阶段，铅球从A 点运动到B 点,其运动状态是匀加速直线运动的,加速距离是2L 段．且出手高度与手臂长及出手角度是有一定的联系，进而合理地细化各个因素对掷远成绩的约束，改进模型Ⅰ．在投掷角度为上进行受力分析，如图(3)由牛顿第二定律可得，ma mg F =-θsin 再由上式可得，θsin g mFa -=………………………………………(3) 又，22022aL v v =-，即22022aL v v += (4)将(3)代入(4)可得，θsin 2222202g L m FL v v -⎪⎭⎫⎝⎛+= ………………………(5) (5)式进一步说明了，出手速度v 与出手角度θ有关，随着θ的增加而减小．模型Ⅰ假设出手速度与出手角度相互独立是不合理的．又根据图(2),有θsin 1'L h h += (6)由模型Ⅰ,同理可以得到铅球脱手后运动的距离θθθ22222cos 22sin 222sin g v h g v g v L +⎪⎪⎭⎫ ⎝⎛+= 将 (4)、(5)、(6)式代入上式整理，得到铅球运动的距离()⎥⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎢⎣⎡⎥⎦⎤⎢⎣⎡-⎪⎭⎫⎝⎛++++-⎪⎭⎫ ⎝⎛+=θθθθθ22220'2220sin sin 22sin 2112sin 2sin 22g L m FL v h g g g L m FL v L 对上式进行化简：将m=7.257kg,2/8.9s m g = 代入上式，再令m h 60.1'= (我国铅球运动员的平均肩高)，代入上式进一步化简得，()⎪⎪⎭⎫ ⎝⎛-++-++⨯θθθθθ2222232222sin sin 6.192756.06.19sin 6.19sin 2756.0sin 1L FL v L FL v ………………(7) 所以,运动员投掷的总成绩θcos 1L L S +=问题3给定出手高度，对于不同的出手速度，要确定最佳的出手角度．显然，是求极值的问题，根据微积分的知识，我们要先求出驻点，首先，模型一中L 对θ求导得，g hv g v g hv v g v d dL θθθθθθθθ22224242cos 82sin sin cos 42cos 2sin 2cos +-+=令0=θd dL,化简后为， 0sin cos 42cos 2sin cos 82sin 2cos 2422242=-++θθθθθθθhgv v hgv v v根据倍角与半角的三角关系，将以上方程转化成关于θ2cos 的方程，然后得，hv g g vgh gh222cos +=+=θ (3)()θθ2sin sin 6.192756.051.0222L FL v L -+=从(3)式可以看出，给定铅球的出手高度h ，出手速度v 变大，相应的最佳出手角度θ也随之变大．对(3)式进行分析，由于0,0>>θh ，所以02cos >θ，则40πθ≤<．所以，最佳出手角度为)arccos(212vgh gh +=θ θ是以π2为周期变化的，当且仅当N k k ∈⎪⎭⎫⎝⎛∈±,4,02ππθ时，πθk 2±为最佳出手角度．特别地，当h=0时（即出手点与落地点在同一高度），最佳出手角度︒=45α3、零件的参数设计粒子分离器某参数（记作y ）由7个零件的参数（记作x x 12，，…x 7）决定，经验公式为：y x x x x x x x x x x x =⎛⎝ ⎫⎭⎪-⎛⎝ ⎫⎭⎪⨯--⎛⎝ ⎫⎭⎪⎡⎣⎢⎢⎤⎦⎥⎥⎛⎝ ⎫⎭⎪-17442126210361532108542056324211667......y 的目标值（记作y 0）为1.50。

2016年美国大学生数学建模大赛A题获奖论文A Hot Bath

Part II Finding the best strategy ...................................................................12 VI. Results ........................................................................................................ 12
The first part has five sections: air’s heat radiation, bathtub wall’s heat radiation, person in, hot water in, bubble existed. We discuss some factors that affect water temperature, such as the shape and the volume of the bathtub and person, especially the motions made by the person in the bathtub because the temperature in the bathtub has a great connection with person. Finally, we get the water temperature variation and distribution model.
In this article, we establish two models. One is water temperature variation and distr one is finding best strategy model. We put forward some acceptable hypothesis to simplify the model. What’s more, we clear the meaning of the word “noticeably”.

2019年全国大学生数学建模竞赛题目A：高压油管的压力控制优秀论文范例三篇(含源代码)

2019年全国大学生数学建模竞赛题目A：高压油管的压力控制优秀论文范例三篇（含源代码）1. 引言高压油管是发动机燃油喷射系统中的重要组成部分，其压力的控制对于发动机的运行稳定性非常关键。

在2019年全国大学生数学建模竞赛中，针对高压油管的压力控制问题，我们进行了一系列研究和分析，探索了解决该问题的优秀方法。

本文将介绍三篇优秀论文范例，并提供源代码供读者参考。

2. 论文一：基于PID控制算法的高压油管压力控制2.1 问题描述本文从数学建模的角度出发，针对高压油管的压力控制问题提出了一种基于PID控制算法的解决方案。

该问题的要求是在给定的工况下，通过控制高压油泵的开关方式，使得一段时间内高压油管内的压力保持在一个预定的范围内。

2.2 算法设计本文提出了基于PID控制算法的高压油管压力控制方案。

PID控制是一种常用的反馈控制算法，通过不断调整控制器的参数，根据当前误差来调整控制信号。

在该方案中，我们将高压油管的压力误差作为PID控制器的输入，根据控制器输出的控制信号，调整高压油泵的开关状态。

通过不断的反馈调整，使得高压油管内的压力稳定在预定范围内。

2.3 仿真与实验结果本文通过对所提出的高压油管压力控制方案进行仿真与实验，验证了该方案的可行性和有效性。

仿真结果表明，通过PID控制算法，可以在较短的时间内将高压油管内的压力控制在预定范围内。

实验结果也进一步验证了方案的有效性。

2.4 源代码# PID控制算法实现def pid_control(p_error, i_error, d_error):Kp =0.5# 比例系数Ki =0.2# 积分系数Kd =0.1# 微分系数control_signal = Kp * p_error + Ki * i_error + Kd * d_errorreturn control_signal# 高压油管压力控制主程序def pressure_control(target_pressure, current_pre ssure, time_step):p_error = target_pressure - current_pressurei_error = p_error * time_stepd_error = (p_error - d_error_prev) / time_ste pcontrol_signal = pid_control(p_error, i_error, d_error)d_error_prev = p_errorreturn control_signal# 实际应用中的使用示例target_pressure =100# 目标压力current_pressure =0# 当前压力time_step =0.1# 时间步长while True:control_signal = pressure_control(target_pres sure, current_pressure, time_step)# 根据控制信号调整高压油泵的开关状态# 更新当前压力值3. 论文二：基于模型预测控制的高压油管压力控制3.1 问题描述本文针对高压油管的压力控制问题，提出了一种基于模型预测控制（MPC）的解决方案。

数学建模获奖论文(优秀范文10篇)11000字

数学建模获奖论文（优秀范文10篇）11000字数学建模竞赛从1992年始，到现如今已成为全国高校规模最大的基础性学科竞赛，也是世界上规模最大的数学建模竞赛。

本篇文章就为大家介绍一些数学建模获奖论文，供给大家欣赏和探讨。

数学建模获奖论文优秀范文10篇之第一篇：高中数学核心素养之数学建模能力培养的研究摘要：数学建模是一种比较重要的能力，教师在进行高中数学教学的过程中应该让学生们学习这种能力，这对于解决高中数学问题是比较有效的，而且对于学生们未来接受高等教育有更重要的意义。

教师在进行高中数学教学的过程中需要让学生们的能力得到锻炼，提升能力是教学的主要目的，学习知识是比较基础的教学目的，教师如果想让学生们的能力得到锻炼应该对教学方法进行更新，高中数学对于很多学生们来说都是比较困难的，所以教师应该不断更新教学方法，让学生们能理解教师的教学目的，而且找到适合自己的学习方法，这也是核心素养的基本内涵。

本文将对高中数学核心素养之数学建模能力培养进行研究。

关键词：高中数学; 核心素养; 数学建模; 能力培养; 应用研究;建模活动是一项比较有创造性的活动，学生们在学习的过程中一定要具备创新思维和自主学习能力，建模活动进行过程中可以让学生们独立，自觉运用数学理论知识去探索以及解决问题，构建模型解决实际问，教学活动中，让学生们的基础知识更加牢固、基本技能得到锻炼是最根本的目的。

学生们的运算能力以及逻辑思维能力也能在建模活动中得到锻炼，提升学生们的空间观念以及增强应用数学意识是延伸目的。

一、对数学建模的基本理解概述高中数学建模最简单的解释就是利用学生们学习过的理论知识来建立数学模型解决遇到的问题。

数学建模的基本过程就是对生活中或者课本中比较抽象问题解决的过程。

通过抽象可以建立刻画出一种较强的数学手段，通过运用数学思维也能观察分析各种事物的基本性质和特点。

学生们可以从复杂的问题中抽离出自己熟悉的模型，然后在利用好数学模型去解决实际问题基本就是事半功倍。

美国中学生数学建模竞赛获奖论文

Abstract
In this paper, we undertake the search and find problem. In two parts of searching, we use different way to design the model, but we use the same algorithm to calculate the main solution. In Part 1, we assume that the possibilities of finding the ring in different paths are different. We give weight to each path according to the possibility of finding the ring in the path. Then we simplify the question as pass as more weight as possible in limited distance. To simplify the calculating, we use Greedy algorithm and approximate optimal solution, and we define the values of the paths(according to the weights of paths) in Greedy algorithm. We calculate the possibility according to the weight of the route and to total weights of paths in the map. In Part 2, firstly, we limit the moving area of the jogger according to the information in the map. Then we use Dijkstra arithmatic to analysis the specific area of the jogger may be in. At last, we use greedy algorithm and approximate optimal solution to get the solution.

高教社杯全国大学生数学建模竞赛获奖论文(精品)

高教社杯全国大学生数学建模竞赛获奖论文（精品）2010高教社杯全国大学生数学建模竞赛编号专用页赛区评阅编号(由赛区组委会评阅前进行编号):赛区评阅记录(可供赛区评阅时使用):评阅人评分备注全国统一编号(由赛区组委会送交全国前编号):全国评阅编号(由全国组委会评阅前进行编号):关于2010年上海世博会影响力的评估——从历史文化交流方面进行讨论摘要本文从各国人民在历史文化方面的交流评估了2010年上海世博会的影响力。

根据题意以及互联网收集到的数据，建立了数学模型并定量估计了上海世博会的影响力，突出上海世博的主题“城市，让生活更美好”的基本理念。

首先，运用灰色聚类法对互联网收集到的数据进行灰类等级划分，再对数据进行无量纲化处理。

其次，建立各灰类白化函数，再对各组数据进行聚类权F运算，进而得出各因素的相应数据。

最后，通过白化函数得到的矩阵和聚类n权运算得到的函数，应用求聚类公式，求得各聚类对象的,,,fd*,LjjLLj，，,jL,1j各灰色聚类系数及结果。

然后应用层次分析法，推导出一种进行加权分析的方法，利用本方法对影响世博会的各个因素进行加权，得出了各个世博城市关于T，通过比较得到上海世博会影影响力的组合权重数据为(0.3634,0.3620,0.2743)响力均高于爱知、汉诺威世博会。

合适的评估体系是本课题的关键。

我们充分利用互联网收集到的数据进行分析及统计，并考虑到方案的可操作性。

通过组合权重数据，得到了三个世博城市关于影响力的权重。

由于此模型不受指数的影响，有很好的灵活性，使得我们可以根据实际情况灵活选取指数，减少模型的工作量，增加模型精度。

关键字:定量估计、层次分析法、灰色聚类法1一、问题重述2010年上海世博会是首次在中国举办的世界博览会。

从1851年伦敦的“万国工业博览会”开始，世博会正日益成为各国人民交流历史文化、展示科技成果、体现合作精神、展望未来发展等的重要舞台。

可以从我们感兴趣的某个侧面，建立数学模型，利用互联网数据，定量评估2010年上海世博会的影响力。

优秀数学建模论文(全国一等奖)

承诺书我们仔细阅读了中国大学生数学建模竞赛的竞赛规则.我们完全明白，在竞赛开始后参赛队员不能以任何方式（包括电话、电子邮件、网上咨询等）与队外的任何人（包括指导教师）研究、讨论与赛题有关的问题。

我们知道，抄袭别人的成果是违反竞赛规则的, 如果引用别人的成果或其他公开的资料（包括网上查到的资料），必须按照规定的参考文献的表述方式在正文引用处和参考文献中明确列出。

我们郑重承诺，严格遵守竞赛规则，以保证竞赛的公正、公平性。

如有违反竞赛规则的行为，我们将受到严肃处理。

我们参赛选择的题号是（从A/B/C/D中选择一项填写）：我们的参赛报名号为（如果赛区设置报名号的话）：所属学校（请填写完整的全名）：参赛队员(打印并签名) ：1.2.3.指导教师或指导教师组负责人(打印并签名)：日期：年月日赛区评阅编号（由赛区组委会评阅前进行编号）：编号专用页赛区评阅编号（由赛区组委会评阅前进行编号）：全国统一编号（由赛区组委会送交全国前编号）：全国评阅编号（由全国组委会评阅前进行编号）：A题:出版社的资源配置摘要本文根据题目的要求建立了合理的有限资源分配优化模型，我们借助多种数学软件的优势挖掘出大量数据潜在的信息，并将其合理运用，在此基础上，以利润最大为目标，长远发展为原则，制定出信息不足条件下的量化综合评价体系，并为出版社在2006年如何合理有效地分配有限的书号资源提供了最佳的分配方案。

在本文所建立的模型中，我们采取了层次分析法（AHP）、数据统计拟合以及整数线性规划相结合的手段，这样既借鉴了层次分析法综合评价的优势，又克服了该法中主观因素的不确定性，使模型更具有科学性，作出了出版社2006年的分配方案，如下表经过对模型的检验，单从生产计划准确度一项来看，模型所得出的结果就比以往的高，这样就首先保证了出版社获得年度稳定利润的前提，其他几个评价指标也都可以得出相似的结论。

以2006年与2005年生产计划的准确度为例，作比较：2005年的各分社平均生产计划的准确度为0.702006年的各分社平均生产计划的准确度为0.85平均准确度提高约21%从数据的对比中，我们很容易看出本模型具有较高的有效性和合理性。

历年美赛数学建模优秀论文大全

2008国际大学生数学建模比赛参赛作品---------WHO所属成员国卫生系统绩效评估作品名称：Less Resources, more outcomes参赛单位：重庆大学参赛时间：2008年2月15日至19日指导老师：何仁斌参赛队员：舒强机械工程学院05级罗双才自动化学院05级黎璨计算机学院05级ContentLess Resources, More Outcomes (4)1. Summary (4)2. Introduction (5)3. Key Terminology (5)4. Choosing output metrics for measuring health care system (5)4.1 Goals of Health Care System (6)4.2 Characteristics of a good health care system (6)4.3 Output metrics for measuring health care system (6)5. Determining the weight of the metrics and data processing (8)5.1 Weights from statistical data (8)5.2 Data processing (9)6. Input and Output of Health Care System (9)6.1 Aspects of Input (10)6.2 Aspects of Output (11)7. Evaluation System I : Absolute Effectiveness of HCS (11)7.1Background (11)7.2Assumptions (11)7.3Two approaches for evaluation (11)1. Approach A : Weighted Average Evaluation Based Model (11)2. Approach B: Fuzzy Comprehensive Evaluation Based Model [19][20] (12)7.4 Applying the Evaluation of Absolute Effectiveness Method (14)8. Evaluation system II: Relative Effectiveness of HCS (16)8.1 Only output doesn’t work (16)8.2 Assumptions (16)8.3 Constructing the Model (16)8.4 Applying the Evaluation of Relative Effectiveness Method (17)9. EAE VS ERE: which is better? (17)9.1 USA VS Norway (18)9.2 USA VS Pakistan (18)10. Less Resources, more outcomes (19)10.1Multiple Logistic Regression Model (19)10.1.1 Output as function of Input (19)10.1.2Assumptions (19)10.1.3Constructing the model (19)10.1.4. Estimation of parameters (20)10.1.5How the six metrics influence the outcomes? (20)10.2 Taking USA into consideration (22)10.2.1Assumptions (22)10.2.2 Allocation Coefficient (22)10.3 Scenario 1: Less expenditure to achieve the same goal (24)10.3.1 Objective function： (24)10.3.2 Constraints (25)10.3.3 Optimization model 1 (25)10.3.4 Solutions of the model (25)10.4. Scenario2: More outcomes with the same expenditure (26)10.4.1Objective function (26)10.4.2Constraints (26)10.4.3 Optimization model 2 (26)10.4.4Solutions to the model (27)15. Strengths and Weaknesses (27)Strengths (27)Weaknesses (27)16. References (28)Less Resources, More Outcomes1. SummaryIn this paper, we regard the health care system (HCS) as a system with input and output, representing total expenditure on health and its goal attainment respectively. Our goal is to minimize the total expenditure on health to archive the same or maximize the attainment under given expenditure.First, five output metrics and six input metrics are specified. Output metrics are overall level of health, distribution of health in the population,etc. Input metrics are physician density per 1000 population, private prepaid plans as % private expenditure on health, etc.Second, to evaluate the effectiveness of HCS, two evaluation systems are employed in this paper:●Evaluation of Absolute Effectiveness(EAE)This evaluation system only deals with the output of HCS，and we define Absolute Total Score (ATS) to quantify the effectiveness. During the evaluation process, weighted average sum of the five output metrics is defined as ATS, and the fuzzy theory is also employed to help assess HCS.●Evaluation of Relative Effectiveness(ERE)This evaluation system deals with the output as well as its input, and also we define Relative Total Score (RTS) to quantify the effectiveness. The measurement to ATS is units of output produced by unit of input.Applying the two kinds of evaluation system to evaluate HCS of 34 countries (USA included), we can find some countries which rank in a higher position in EAE get a relatively lower rank in ERE, such as Norway and USA, indicating that their HCS should have been able to archive more under their current resources .Therefore, taking USA into consideration, we try to explore how the input influences the output and archive the goal: less input, more output. Then three models are constructed to our goal:●Multiple Logistic RegressionWe model the output as function of input by the logistic equation. In more detains, we model ATS (output) as the function of total expenditure on health system. By curve fitting, we estimate the parameters in logistic equation, and statistical test presents us a satisfactory result.●Linear Optimization Model on minimizing the total expenditure on healthWe try to minimize the total expenditure and at the same time archive the same, that is to get a ATS of 0.8116. We employ software to solve the model, and by the analysis of the results. We cut it to 2023.2 billion dollars, compared to the original data 2109.8 billion dollars.●Linear Optimization Model on maximizing the attainment. We try to maximize the attainment (absolute total score) under the same total expenditure in2007.And we optimize the ATS to 0.8823, compared to the original data 0.8116.Finally, we discuss strengths and weaknesses of our models and make necessary recommendations to the policy-makers。

正确写作美国大学生数学建模竞赛论文

1）、鉴别阶段：（10分钟）
所有论文在此阶段按其质量分别归入一下三类：第一类是可以进入下一评审阶段的论文（略少于二分之一）；第二类是满足竞赛要求，但不足以进入下一评审阶段的论文（这一类就被定为合格论文）；第三类是不符合竞赛要求的论文（不合格论文）。由于在第一阶段中，评委只有10分钟左右的时间评审一篇论文，因此评委常常只能通过阅读摘要来判断论文水平的高低。
例如，2010年MCM竞赛中有一道赛题，要求参赛小组根据以往的作案地点预测连环犯罪的位置。
3.1）、假设条件和解释解答这道赛题的重点是犯罪活动方式。在一篇题为 “Centroids, Clusters, and Crime: Anchoring the Geographic Profiles of Serial Criminals”的论文中，有一条假设是“罪犯的活动不受限制”，但罪犯是在市区的活动，实际上会受到街道的布局及街道两旁建筑物的限制。由于街道布局通常类似于网格，所以参赛小组对这个假设做了如下解释： Criminal’s movement is unconstrained. Because of the difficulty of finding real-world distance data, we invoke the „Manhattan assumption‟: There are enough streets and sidewalks in a sufficiently grid-like pattern that movements along real-world movement routes is the same as „straight-line‟ movement in a space discretized into city blocks…

数学建模获奖论文模板范文

数学建模获奖论文模板范文一、我校学生数学建模现状3.目前我校只开设了一门数学方面的公共选修课《数学建模》，一共16次课，仅仅靠课堂上讲的内容让学生来参加数学建模竞赛远远不够，另外，学生又要同时兼顾其他专业课程，因此学习效果不好。

5.我校学生参加数学建模的积极性不高，我校已经连续参加几年的数学建模竞赛，但最多的也就5个队，仍有多数学生称未听过有这项比赛，说明宣传不是很到位。

6.目前组队参赛的任务是交给基础部来完成，而基础部没有学生，这就会造成找队员困难的问题。

二、参加数学建模比赛的意义1.有利于培养学生综合解决问题的能力因为数学建模最后提交的成果是交一篇完整的论文，对于大多数学生来说，都是第一次，它可以提高学生如何把数学知识用到实际生活中的能力，提高学生合理利用网络查阅资料的能力，提高学生的创新意识和团队协作能力等。

很多参赛学生事后感叹到团队合作能力对于建模比赛很重要，这对他们以后参加工作也会有很好的帮助。

2.有利于促进高职数学课程的改革三、数学建模课的发展建议1.把数学建模的管理层次上升到学院，因为只有学院的大力支持，领导的高度重视才是提高高职学生数学建模能力的首要条件，而且只有学院的倡导和支持，各部门在宣传数学建模方面时才会更加尽职尽责，不会出现推诿的现象。

3.平时开设数学建模选修课，假期集中培训备战国赛，由于我校的数学建模课一般开设在大一的下学期，而技能大赛的比赛时间通常是选修课开课之前，这就导致了学生参加技能大赛时根本不知道数学建模比赛比的是什么。

而且选修课只有一个老师教，力度太小。

应该是大一开学就开始开设相关的数学建模选修课，几个数学老师分工，每个数学老师讲授一块内容，这样学生了解的知识面会更广一些。

另外，必须赛前集中培训，因为平时的选修课只是让学生了解，但并没有让他们系统的练习，所以赛前培训就是重点讲数学建模习题，并让学生以三人一个小组模拟训练。

4.技能大赛的数学建模比赛应该和学校其他教学系的比赛错开时间，因为学院的技能大赛一般是三天，多数项目的比赛时间通常只有半天，但数学建模恰恰是技能大赛中最特殊的一项比赛，首先是耗时长，正规的数学建模比赛是需要三天的时间，需要学生选定题目后在三天的时间里选定题目后完成一篇完整的论文;其次是必须三人一项小组，由于数学建模的工作量较大，需要三个人共同协作，缺少一个队员就会拖延整个小组的工作进度;再者数学建模比赛期间学生是比较自由的，可以上网，可以和其他人讨论。

精选五篇数学建模优秀论文

精选五篇数学建模优秀论文一、基于深度学习的股票价格预测模型研究随着金融市场的发展，股票价格预测成为投资者关注的焦点。

本文提出了一种基于深度学习的股票价格预测模型，通过分析历史数据，预测未来股票价格走势。

实验结果表明，该模型具有较高的预测精度和鲁棒性，为投资者提供了一种有效的决策支持工具。

二、基于优化算法的智能交通信号控制策略研究随着城市化进程的加快，交通拥堵问题日益严重。

本文提出了一种基于优化算法的智能交通信号控制策略，通过优化信号灯的配时方案，实现交通流量的均衡分配，提高道路通行能力。

实验结果表明，该策略能够有效缓解交通拥堵，提高交通效率。

三、基于数据挖掘的电商平台用户行为分析电商平台在电子商务领域发挥着重要作用，用户行为分析对于电商平台的发展至关重要。

本文提出了一种基于数据挖掘的电商平台用户行为分析模型，通过分析用户购买行为、浏览行为等数据，挖掘用户偏好和需求。

实验结果表明，该模型能够有效识别用户行为特征，为电商平台提供个性化的推荐服务。

四、基于机器学习的疾病预测模型研究疾病预测对于公共卫生管理具有重要意义。

本文提出了一种基于机器学习的疾病预测模型，通过分析历史疾病数据，预测未来疾病的发生趋势。

实验结果表明，该模型具有较高的预测精度和可靠性，为疾病预防控制提供了一种有效的手段。

五、基于模糊数学的农业生产决策支持系统研究农业生产决策对于提高农业效益和农民收入具有重要意义。

本文提出了一种基于模糊数学的农业生产决策支持系统，通过分析农业环境、市场需求等因素，为农民提供合理的生产决策建议。

实验结果表明，该系统能够有效提高农业生产效益，促进农业可持续发展。