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HEURISTIC MODELING FOR A DYNAMIC AND GOAL PROGRAMMING IN PRODUCTION PLANNING OF CONTINUOUS MANUFACTURING SYSTEMS 被引量:2
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作者 JAHAN A ABDOLSHAH M 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期110-113,共4页
At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive... At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive evaluation the advanced operation research techniques can be used in continuous production systems in developing countries very widely, because of initial inadequate plant layout, stage by stage development of production lines, the purchase of second hand machineries from various countries, plurality of customers. A case of production system planning is proposed for a chemical company in which the above mentioned conditions are almost presented. The goals and constraints in this issue are as follows: (1) Minimizing deviation of customer's requirements. (2) Maximizing the profit. (3) Minimizing the frequencies of changes in formula production. (4) Minimizing the inventory of final products. (5) Balancing the production sections with regard to rate in production. (6) Limitation in inventory of raw material. The present situation is in such a way that various techniques such as goal programming, linear programming and dynamic programming can be used. But dynamic production programming issues are divided into two categories, at first one with limitation in production capacity and another with unlimited production capacity. For the first category, a systematic and acceptable solution has not been presented yet. Therefore an innovative method is used to convert the dynamic situation to a zero- one model. At last this issue is changed to a goal programming model with non-linear limitations with the use of GRG algorithm and that's how it is solved. 展开更多
关键词 Heuristic model Dynamic programming goal programming production planning
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Goal Programming for Investment Portfolio and Its Application
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作者 易树平 《Journal of Chongqing University》 CAS 2002年第1期27-31,共5页
To solve the problem of investment portfolio with single goal of maximal NPV, a 0- 1 programming model was proposed and proved effective; and to solve that concerning more elements of a project such as risk level and ... To solve the problem of investment portfolio with single goal of maximal NPV, a 0- 1 programming model was proposed and proved effective; and to solve that concerning more elements of a project such as risk level and social benefit, a goal programming model is then introduced. The latter is a linear programming model adopting slack variable called deviation variable to turn inequation constraint into equation constraint, introducing a priority factor to denote different importance of the goals. A case study has demonstrated that this goal programming model can give different results according to different priority requirement of each objective. 展开更多
关键词 goal programming Investment portfolio Optimal model
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Weekly Fleet Assignment Model and Algorithm 被引量:1
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作者 朱星辉 朱金福 巩在武 《Journal of Southwest Jiaotong University(English Edition)》 2007年第3期231-235,共5页
A 0-1 integer programming model for weekly fleet assignment was put forward based on linear network and weekly flight scheduling in China. In this model, the objective function is to maximize the total profit of fleet... A 0-1 integer programming model for weekly fleet assignment was put forward based on linear network and weekly flight scheduling in China. In this model, the objective function is to maximize the total profit of fleet assignment, subject to the constraints of coverage, aircraft flow balance, fleet size, aircraft availability, aircraft usage, flight restriction, aircraft seat capacity, and stopover. Then the branch-and-bound algorithm based on special ordered set was applied to solve the model. At last, a real- wofld case study on an airline with 5 fleets, 48 aircrafts and 1 786 flight legs indicated that the profit increase was ¥ 1 591276 one week and the running time was no more than 4 rain, which shows that the model and algorithm are fairly good for domestic airline. 展开更多
关键词 Flight scheduling Fleet assignment problem 0-1 Integer programming model Branch-and-bound algorithm
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A Glorious Literature on Linear Goal Programming Algorithms 被引量:1
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作者 Ukamaka Cynthia Orumie Daniel Ebong 《American Journal of Operations Research》 2014年第2期59-71,共13页
In the last several years, there has been a marked improvement in the development of new algorithms for solving Linear Goal programming (LGP). This paper presents a survey of current methods for LGP.
关键词 Linear goal programming algorithmS CURRENT Methods
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Application of Dynamic Programming Algorithm Based on Model Predictive Control in Hybrid Electric Vehicle Control Strategy 被引量:1
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作者 Xiaokan Wang Qiong Wang 《Journal on Internet of Things》 2020年第2期81-87,共7页
A good hybrid vehicle control strategy cannot only meet the power requirements of the vehicle,but also effectively save fuel and reduce emissions.In this paper,the construction of model predictive control in hybrid el... A good hybrid vehicle control strategy cannot only meet the power requirements of the vehicle,but also effectively save fuel and reduce emissions.In this paper,the construction of model predictive control in hybrid electric vehicle is proposed.The solving process and the use of reference trajectory are discussed for the application of MPC based on dynamic programming algorithm.The simulation of hybrid electric vehicle is carried out under a specific working condition.The simulation results show that the control strategy can effectively reduce fuel consumption when the torque of engine and motor is reasonably distributed,and the effectiveness of the control strategy is verified. 展开更多
关键词 State of charge model predictive control dynamic programming algorithm OPTIMIZATION
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A Weighted Goal Programming Model for the DASH Diet Problem: Comparison with the Linear Programming DASH Diet Model
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作者 Anayo Charles Iwuji Emeka Uchendu Agwu 《American Journal of Operations Research》 2017年第5期307-322,共16页
A Linear Programming DASH diet model for persons with hypertension has previously been formulated and daily minimum cost diet plans that satisfy the DASH diets’ tolerable intake level of the nutrients for 1500 mg a d... A Linear Programming DASH diet model for persons with hypertension has previously been formulated and daily minimum cost diet plans that satisfy the DASH diets’ tolerable intake level of the nutrients for 1500 mg a day Sodium level and different daily calorie levels were obtained using sample foods from the DASH diet eating plan chart. But the limitation in the use of linear programming model in selecting diet plans to meet specific nutritional requirements which normally results in the oversupply of certain nutrients was evident in the linear programming DASH diet plan obtained as the nutrient level of the diet plans obtained had wide deviations of from the DASH diets’ tolerable upper and lower intake level for the given calorie and sodium levels. Hence the need for a model that gives diet plans with minimized nutrients’ level deviations from the DASH diets’ tolerable intake level for different daily calorie and sodium level at desired cost. A weighted Goal Programming DASH diet model that minimizes the daily cost of the DASH eating plan as well as deviations of the diets’ nutrients content from the DASH diet’s tolerable intake levels is hereby presented in this work. The formulated weighted goal programming DASH diet model is further illustrated using chosen sample foods from the DASH food chart as used in the work on the linear programming DASH diet model for a 1500 mg sodium level and 2000 calories a day diet plan as well as for 1800, 2200, 2400, 2600, 2800 and 3000 daily calorie levels. A comparison of the DASH nutrients’ composition of the weighted Goal Programming DASH diet plans and those of the linear programming DASH diet plans were carried out at this sodium level and the different daily calorie levels. It was evident from the results of the comparison that the weighted goal programming DASH diet plans has minimized deviations from the DASH diet’s tolerable intake levels than those of the linear programming DASH diet plans. 展开更多
关键词 DASH (Dietary Approaches to Stop Hypertension) DIET model HYPERTENSION DIET model Minimum Nutrient Deviation DIET Plan WEIGHTED goal programming DIET model Linear and goal programming Comparison
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An Evolutionary Firefly Algorithm, Goal Programming Optimization Approach for Setting the Osmotic Dehydration Parameters of Papaya
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作者 Ting Cao Julian Scott Yeomans 《Journal of Software Engineering and Applications》 2017年第2期128-142,共15页
An evolutionary nature-inspired Firefly Algorithm (FA) is employed to set the optimal osmotic dehydration parameters in a case study of papaya. In the case, the functional form of the dehydration model is established ... An evolutionary nature-inspired Firefly Algorithm (FA) is employed to set the optimal osmotic dehydration parameters in a case study of papaya. In the case, the functional form of the dehydration model is established via a response surface technique with the resulting optimization formulation being a non-linear goal programming model. For optimization, a computationally efficient, FA-driven method is employed and the resulting solution is shown to be superior to those from previous approaches for determining the osmotic process parameters. The final component of this study provides a computational experimentation performed on the FA to illustrate the relative sensitivity of this evolutionary metaheuristic approach over a range of the two key parameters that most influence its running time-the number of iterations and the number of fireflies. This sensitivity analysis revealed that for intermediate-to-high values of either of these two key parameters, the FA would always determine overall optimal solutions, while lower values of either parameter would generate greater variability in solution quality. Since the running time complexity of the FA is polynomial in the number of fireflies but linear in the number of iterations, this experimentation shows that it is more computationally practical to run the FA using a “reasonably small” number of fireflies together with a relatively larger number of iterations than the converse. 展开更多
关键词 FIREFLY algorithm Non-Linear goal programming Process Parameter Optimization OSMOTIC DEHYDRATION PAPAYA
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The parallel 3D magnetotelluric forward modeling algorithm 被引量:28
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作者 Tan Handong Tong Tuo Lin Changhong 《Applied Geophysics》 SCIE CSCD 2006年第4期197-202,共6页
The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the dat... The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the data in the frequency domain, which is very suitable for parallel computation. With the advantage of MPI and based on an analysis of the flow of the 3D magnetotelluric serial forward algorithm, we suggest the idea of parallel computation and apply it. Three theoretical models are tested and the execution efficiency is compared in different situations. The results indicate that the parallel 3D forward modeling computation is correct and the efficiency is greatly improved. This method is suitable for large size geophysical computations. 展开更多
关键词 Magnetotelluric 3D forward modeling MPI parallel programming design 3D staggered-grid finite difference method parallel algorithm.
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A Multiple Model Approach to Modeling Based on LPF Algorithm 被引量:2
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作者 Li, N. Li, S. Xi, Y. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第3期64-70,共7页
Input-output data fitting methods are often used for unknown-structure nonlinear system modeling. Based on model-on-demand tactics, a multiple model approach to modeling for nonlinear systems is presented. The basic i... Input-output data fitting methods are often used for unknown-structure nonlinear system modeling. Based on model-on-demand tactics, a multiple model approach to modeling for nonlinear systems is presented. The basic idea is to find out, from vast historical system input-output data sets, some data sets matching with the current working point, then to develop a local model using Local Polynomial Fitting (LPF) algorithm. With the change of working points, multiple local models are built, which realize the exact modeling for the global system. By comparing to other methods, the simulation results show good performance for its simple, effective and reliable estimation. 展开更多
关键词 algorithmS Computer simulation Data structures Input output programs Mathematical models Parameter estimation POLYNOMIALS
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Prediction of Concrete Faced Rock Fill Dams Settlements Using Genetic Programming Algorithm 被引量:3
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作者 Seyed Morteza Marandi Seyed Mahmood VaeziNejad Elyas Khavari 《International Journal of Geosciences》 2012年第3期601-609,共9页
In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries a... In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries across the world is gathered with their reported settlements. The results showed that the GP model is able to estimate the dam settlement properly based on four properties, void ratio of dam’s body (e), height (H), vertical deformation modulus (Ev) and shape factor (Sc) of the dam. For verification of the model applicability, obtained results compared with other research methods such as Clements’s formula and the finite element model. The comparison showed that in all cases the GP model led to be more accurate than those of performed in literature. Also a proper compatibility between the GP model and the finite element model was perceived. 展开更多
关键词 CONCRETE FACED Rock-Fill DAMS SETTLEMENT Genetic programming algorithm Finite Element model
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Multi-objective planning model for simultaneous reconfiguration of power distribution network and allocation of renewable energy resources and capacitors with considering uncertainties 被引量:9
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作者 Sajad Najafi Ravadanegh Mohammad Reza Jannati Oskuee Masoumeh Karimi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1837-1849,共13页
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a... This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration. 展开更多
关键词 optimal reconfiguration renewable energy resources sitting and sizing capacitor allocation electric distribution system uncertainty modeling scenario based-stochastic programming multi-objective genetic algorithm
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Parallel Machine Scheduling Models with Fuzzy Parameters and Precedence Constraints: A Credibility Approach
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期231-236,共6页
A method for modeling the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure is provided. For the given n jobs to be processed on m machines, it is assum... A method for modeling the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure is provided. For the given n jobs to be processed on m machines, it is assumed that the processing times and the due dates are nonnegative fuzzy numbers and all the weights are positive, crisp numbers. Based on credibility measure, three parallel machine scheduling problems and a goal-programming model are formulated. Feasible schedules are evaluated not only by their objective values but also by the credibility degree of satisfaction with their precedence constraints. The genetic algorithm is utilized to find the best solutions in a short period of time. An illustrative numerical example is also given. Simulation results show that the proposed models are effective, which can deal with the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure. 展开更多
关键词 parallel machine scheduling programming model possibility measure credibility measure fuzzy number genetic algorithm
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Predictive Mathematical and Statistical Modeling of the Dynamic Poverty Problem in Burundi: Case of an Innovative Economic Optimization System
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作者 Fulgence Nahayo Ancille Bagorizamba +1 位作者 Marc Bigirimana Irene Irakoze 《Open Journal of Optimization》 2021年第4期101-125,共25页
The mathematical and statistical modeling of the problem of poverty is a major challenge given Burundi’s economic development. Innovative economic optimization systems are widely needed to face the problem of the dyn... The mathematical and statistical modeling of the problem of poverty is a major challenge given Burundi’s economic development. Innovative economic optimization systems are widely needed to face the problem of the dynamic of the poverty in Burundi. The Burundian economy shows an inflation rate of -1.5% in 2018 for the Gross Domestic Product growth real rate of 2.8% in 2016. In this research, the aim is to find a model that contributes to solving the problem of poverty in Burundi. The results of this research fill the knowledge gap in the modeling and optimization of the Burundian economic system. The aim of this model is to solve an optimization problem combining the variables of production, consumption, budget, human resources and available raw materials. Scientific modeling and optimal solving of the poverty problem show the tools for measuring poverty rate and determining various countries’ poverty levels when considering advanced knowledge. In addition, investigating the aspects of poverty will properly orient development aid to developing countries and thus, achieve their objectives of growth and the fight against poverty. This paper provides a new and innovative framework for global scientific research regarding the multiple facets of this problem. An estimate of the poverty rate allows good progress with the theory and optimization methods in measuring the poverty rate and achieving sustainable development goals. By comparing the annual food production and the required annual consumption, there is an imbalance between different types of food. Proteins, minerals and vitamins produced in Burundi are sufficient when considering their consumption as required by the entire Burundian population. This positive contribution for the latter comes from the fact that some cows, goats, fishes, ···, slaughtered in Burundi come from neighboring countries. Real production remains in deficit. The lipids, acids, calcium, fibers and carbohydrates produced in Burundi are insufficient for consumption. This negative contribution proves a Burundian food deficit. It is a decision-making indicator for the design and updating of agricultural policy and implementation programs as well as projects. Investment and economic growth are only possible when food security is mastered. The capital allocated to food investment must be revised upwards. Demographic control is also a relevant indicator to push forward Burundi among the emerging countries in 2040. Meanwhile, better understanding of the determinants of poverty by taking cultural and organizational aspects into account guides managers for poverty reduction projects and programs. 展开更多
关键词 Poverty Problem Mathematical modeling Applied Statistics Operational Research Symplectic Partitioned Runge Kutta algorithm Dynamic programming Matlab and Simulink AMPL KNITRO Gurobi Economic Optimization Technology Transfer Incubation of Results Sustainable Development goals
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Design of a Computational Heuristic to Solve the Nonlinear Liénard Differential Model
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作者 Li Yan Zulqurnain Sabir +3 位作者 Esin Ilhan Muhammad Asif Zahoor Raja WeiGao Haci Mehmet Baskonus 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期201-221,共21页
In this study,the design of a computational heuristic based on the nonlinear Liénard model is presented using the efficiency of artificial neural networks(ANNs)along with the hybridization procedures of global an... In this study,the design of a computational heuristic based on the nonlinear Liénard model is presented using the efficiency of artificial neural networks(ANNs)along with the hybridization procedures of global and local search approaches.The global search genetic algorithm(GA)and local search sequential quadratic programming scheme(SQPS)are implemented to solve the nonlinear Liénard model.An objective function using the differential model and boundary conditions is designed and optimized by the hybrid computing strength of the GA-SQPS.The motivation of the ANN procedures along with GA-SQPS comes to present reliable,feasible and precise frameworks to tackle stiff and highly nonlinear differentialmodels.The designed procedures of ANNs along with GA-SQPS are applied for three highly nonlinear differential models.The achieved numerical outcomes on multiple trials using the designed procedures are compared to authenticate the correctness,viability and efficacy.Moreover,statistical performances based on different measures are also provided to check the reliability of the ANN along with GASQPS. 展开更多
关键词 Nonlinear Liénard model numerical computing sequential quadratic programming scheme genetic algorithm statistical analysis artificial neural networks
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Bus frequency optimization in a large-scale multi-modal transportation system:integrating 3D-MFD and dynamic traffic assignment
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作者 Kai Yuan Dandan Cui Jiancheng Long 《Digital Transportation and Safety》 2023年第4期241-252,共12页
A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result... A properly designed public transport system is expected to improve traffic efficiency.A high-frequency bus service would decrease the waiting time for passengers,but the interaction between buses and cars might result in more serious congestion.On the other hand,a low-frequency bus service would increase the waiting time for passengers and would not reduce the use of private cars.It is important to strike a balance between high and low frequencies in order to minimize the total delays for all road users.It is critical to formulate the impacts of bus frequency on congestion dynamics and mode choices.However,as far as the authors know,most proposed bus frequency optimization formulations are based on static demand and the Bureau of Public Roads function,and do not properly consider the congestion dynamics and their impacts on mode choices.To fill this gap,this paper proposes a bi-level optimization model.A three-dimensional Macroscopic Fundamental Diagram based modeling approach is developed to capture the bi-modal congestion dynamics.A variational inequality model for the user equilibrium in mode choices is presented and solved using a double projection algorithm.A surrogate model-based algorithm is used to solve the bi-level programming problem. 展开更多
关键词 Three-dimensional macroscopic fundamental diagram Dynamic traffic assignment Bi-level programming model Double projection algorithm Surrogate model-based algorithm
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基于Deep Forest算法的对虾急性肝胰腺坏死病(AHPND)预警数学模型构建
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作者 王印庚 于永翔 +5 位作者 蔡欣欣 张正 王春元 廖梅杰 朱洪洋 李昊 《渔业科学进展》 CSCD 北大核心 2024年第3期171-181,共11页
为预报池塘养殖凡纳对虾(Penaeus vannamei)急性肝胰腺坏死病(AHPND)的发生,自2020年开始,笔者对凡纳对虾养殖区开展了连续监测工作,包括与疾病发生相关的环境理化因子、微生物因子、虾体自身健康状况等18个候选预警因子指标,通过数据... 为预报池塘养殖凡纳对虾(Penaeus vannamei)急性肝胰腺坏死病(AHPND)的发生,自2020年开始,笔者对凡纳对虾养殖区开展了连续监测工作,包括与疾病发生相关的环境理化因子、微生物因子、虾体自身健康状况等18个候选预警因子指标,通过数据标准化处理后分析病原、宿主与环境之间的相关性,对候选预警因子进行筛选,基于Python语言编程结合Deep Forest、Light GBM、XGBoost算法进行数据建模和预测性能评判,仿真环境为Python2.7,以预警因子指标作为输入样本(即警兆),以对虾是否发病指标作为输出结果(即警情),根据输入样本和输出结果各自建立输入数据矩阵和目标数据矩阵,利用原始数据矩阵对输入样本进行初始化,结合函数方程进行拟合,拟合的源代码能利用已知环境、病原及对虾免疫指标数据对目标警情进行预测。最终建立了基于Deep Forest算法的虾体(肝胰腺内)细菌总数、虾体弧菌(Vibrio)占比、水体细菌总数和盐度的4维向量预警预报模型,准确率达89.00%。本研究将人工智能算法应用到对虾AHPND发生的预测预报,相关研究结果为对虾AHPND疾病预警预报建立了预警数学模型,并为对虾健康养殖和疾病防控提供了技术支撑和有力保障。 展开更多
关键词 对虾 急性肝胰腺坏死病 预警数学模型 Deep Forest算法 PYTHON语言
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高速公路货车空车差异化费率优化的双层规划方法
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作者 段莉珍 何明卫 +1 位作者 何民 普荣慧 《交通运输系统工程与信息》 EI CSCD 北大核心 2024年第5期197-204,共8页
为解决高速公路货车由计重收费调整为按车型收费导致货车空车分流的问题,本文建立一种基于双层规划模型的货车空车分车型差异化费率优化方法。首先,以高速公路经营主体实现收费收益最大化为目标构建上层规划模型,考虑高速公路通行效率... 为解决高速公路货车由计重收费调整为按车型收费导致货车空车分流的问题,本文建立一种基于双层规划模型的货车空车分车型差异化费率优化方法。首先,以高速公路经营主体实现收费收益最大化为目标构建上层规划模型,考虑高速公路通行效率提升及增量货车空车增加的管养支出;其次,以道路使用者实现出行效用最大化为目标构建下层规划模型,构建基于逻辑回归模型和随机效用最大化理论的货车空车出行效用函数,分析货车空车特性变量对出行效用的影响;然后,采用多层神经网络模型及三次艾尔米特插值法,预测不同费率优惠下高速公路货车空车增量交通量,作为上下层联系变量;最后,以高速公路与平行老路构成的运输通道为例,采用内存受限的拟牛顿优化算法(L-BFGS-B)求解高速公路货车空车分车型最优费率。结果表明:高速公路费率折扣率对货车空车各车型出行选择影响最为显著;此外,车籍地对一类、四类货车空车出行选择影响较大,运输类型对二类、三类和六类货车空车出行选择影响较大;与现行费率方案相比,优化后的费率方案年度增加通行费收入3941万元,高速公路通行效率提升4.17%,货车空车平均每车出行效用增加3.51。 展开更多
关键词 交通运输经济 差异化费率优化 双层规划模型 货车空车 L-BFGS-B算法
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基于高频组合片段-基因表达式编程算法的轨道交通地面沉降预测模型
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作者 胡珉 卢孟栋 《城市轨道交通研究》 北大核心 2024年第8期206-210,共5页
[目的]地面沉降预测和控制是轨道交通盾构法隧道施工中最为关注的问题之一。为了解决现有地面沉降预测和控制中存在的模型表达过于复杂且缺乏解释性的问题,需要一种既简洁清晰,又能够描述复杂问题的可解释模型,GEP(基因表达式编程)算法... [目的]地面沉降预测和控制是轨道交通盾构法隧道施工中最为关注的问题之一。为了解决现有地面沉降预测和控制中存在的模型表达过于复杂且缺乏解释性的问题,需要一种既简洁清晰,又能够描述复杂问题的可解释模型,GEP(基因表达式编程)算法提供了这种可能性,因此需对基于HFS(高频组合片段)-GEP算法的轨道交通地面沉降预测模型进行深入研究。[方法]以杭绍城际铁路某区段盾构隧道工程为依托,选取盾构施工过程中的土舱压力、刀盘扭矩、刀盘转速、推进速度、总推力、隧道埋深及盾尾注浆量等参数作为关键输入型施工参数,地面沉降作为输出型施工参数,通过备选公式集筛选以及HFS选取,建立基于HFS-GEP算法的轨道交通地面沉降预测模型。利用该模型对第180环—第210环区段的关键施工参数进行优化调整,分析盾构施工参数变化对地面最终沉降的影响效果。[结果及结论]基于HFS-GEP算法的地面沉降预测模型可以反映盾构施工参数与地面最终沉降的显式关系;相较于传统GEP算法的地面沉降预测模型,该模型准确度更高,结构更为简洁,且收敛速度更快。通过对盾构关键施工参数进行优化调整,该模型可将第180环—第210环区段的最终沉降量控制在10 mm以内。 展开更多
关键词 轨道交通 地面沉降预测模型 高频组合片段 基因表达式编程算法
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任务并行编程模型下排列熵算法的并行实现
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作者 李维权 《软件工程》 2024年第2期40-43,共4页
排列熵算法随着嵌入维数的增大,运算规模将会呈平方级数增大,计算时效性问题突出,亟待解决。为此,提出一种基于任务并行编程模型的线程级并行方法,通过任务并行运行系统(StarPU)将密集型计算划分为多个独立的任务,再由调度器将任务调度... 排列熵算法随着嵌入维数的增大,运算规模将会呈平方级数增大,计算时效性问题突出,亟待解决。为此,提出一种基于任务并行编程模型的线程级并行方法,通过任务并行运行系统(StarPU)将密集型计算划分为多个独立的任务,再由调度器将任务调度到不同的CPU上执行,实现排列熵算法的并行化。基于StarPU的排列熵并行算法与串行程序相比较,加速比为23.79倍,相较于OpenMP(一种用于共享内存并行系统的并行计算方案),在分配28个线程时,加速比为1.17倍,结果表明该方法能够有效实现排列熵算法的加速执行。 展开更多
关键词 排列熵算法 任务并行编程模型 OPENMP StarPU
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基于CSA-AFSA算法的集装箱港口连续型泊位分配优化
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作者 初良勇 章嘉文 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第10期61-69,共9页
为提升集装箱港口运营效率,笔者研究了考虑潮汐因素与泊位偏好的连续型泊位分配问题。引入了船舶时空矩形不可重叠约束和潮汐时间窗约束,构建以最小化船舶等待、延迟离港、泊位偏离以及在港期间油耗费用和最小为目标的混合整数线性规划... 为提升集装箱港口运营效率,笔者研究了考虑潮汐因素与泊位偏好的连续型泊位分配问题。引入了船舶时空矩形不可重叠约束和潮汐时间窗约束,构建以最小化船舶等待、延迟离港、泊位偏离以及在港期间油耗费用和最小为目标的混合整数线性规划模型;根据模型特征,采用CPLEX求解软件、鱼群算法、布谷鸟搜索算法和布谷鸟鱼群混合算法进行求解,以计划周期为36 h的20个不同规模的船舶到港数据为研究算例,通过算例求解得到符和潮汐时间窗、泊位偏好等要求的泊位分配方案。算例求解表明:算例规模较小时,CPLEX可以在较短时间内求出最优泊位分配方案;算例规模较大时,CPLEX求解时间较长,布谷鸟鱼群混合算法可以在平均3 min内求出与CPLEX差距为0.39%~4.20%的次优解;不同算法间的对比表明,布谷鸟鱼群混合算法求解能力更优,混合算法所得泊位分配方案中,乘潮船舶的进出港时刻均在潮汐高水位时段,且85%以上的船舶在偏好泊靠点200 m内接受装卸服务。 展开更多
关键词 港口与航道工程 布谷鸟鱼群混合算法 连续型泊位分配 混合整数线性规划模型 潮汐因素 泊位偏好
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