|
所在平台: Udemy |
课程主页: https://www.udemy.com/course/transportation-model-in-operations-research/
课程评论：没有评论
课程名称：运筹学中的运输模型 概述：本课程旨在帮助学员理解和掌握运输领域中使用的各种模型。课程分为两个阶段：第一阶段是初始基本可行解（IBFS），包括以下方法： a) 西北角法 b) 最小成本法 c) 佛戈尔近似法 第二阶段是使用以下方法求解最优解： a) 步骤石法 b) 修改分配法（MODI法） 此外，课程还将深入讲解不平衡运输问题和退化情况。运输模型最早由E.L.希奇科克于1941年提出，1949年由T.C.库普曼进行了改进，而线性规划的运输模型在1951年由乔治·D·丹齐格首次阐述，自此以来，运输问题得到了进一步的发展。运输问题的解决过程分为两个阶段： I）初始最优运输成本 II）总最小运输成本 1) 西北角法：根据此方法，首次分配在表格的左上角单元格（即西北角）进行。分配的量要么耗尽第一行的供应，要么满足第一列的需求。如果供应耗尽，则移动到下一行，选择第一列，并以类似方式进行新的分配；如果需求满足，则向下一个列移动，直到所有供应和需求都得到满足。 2) 最小成本法：顾名思义，该方法基于运输表中具有最小值的单元格。在此方法中，选择运输表中所有行或列中运输成本最低的单元格。比较相应的供应和需求，尽可能多地分配单位，并删除供应或需求耗尽的行或列。重复此步骤，直到所有供应和需求都得以满足。 3) 佛戈尔近似法：佛戈尔近似法基于惩罚，即行和列中两个最小成本单元格之间的差异。计算每一行和列的惩罚后，选择惩罚最高的行或列。在对应的行或列中，选择成本最低的单元格，分配尽可能多的单位，同时删除供应耗尽或需求满足的行或列。重复这些步骤，直到所有的供应和需求都得到满足。 通过本课程的学习，学员将掌握运输模型的应用，提升运筹学方面的能力。
This course will help in understanding and gaining insights on various models used in Transportation:I phase: Initial Basic Feasible Solution (IBFS)a) North West Corner Methodb) Least Cost Methodc) Vogels Approximation MethodII Phase: Optimum Solution using:a) Stepping Stone Methodb) Modified Distribution Method (MODI Method)This course will also provide valuable explanation on:Unbalanced Transportation ProblemsDegeneracy SituationsThe transportation model was described by E.L.Hitchcock in 1941. It was further improved by T.C.Koopmans in 1949. The linear programming formulation of the transportation was initially stated by George B.Dantizig in 1951. Since then Transportation has been further developed. Transportation problems are solved in two phases:I) Initial optimum Transportation costII) Total Minimum Transportation cost1) North West Corner MethodAccording to this method the first allocation is made to the cell occupying the upper left hand or North West corner of the table. Moreover the allotment is of such magnitude that either the supply of the first row or factory is exhausted or the demand of the first column or warehouse is satisfied. If the supply of the row is exhausted then we move down the next row and select the first column and make another allocation in the similar way or if the demand of the column is satisfied then we move towards the next column and make allocation until all the supplies and demands are exhausted.2) Least Cost MethodAs the name suggests this method is based on the cost cell having the least value out of the whole lot.In this method the cell with the minimum transportation cost among all the rows or columns of the transportation table is selected.Allocate as many units as possible after comparing the corresponding supply and demand.Further delete that row or column whose supply and demand is exhausted or satisfied. Repeat the above step until all the supplies are exhausted and the demands are satisfied.3) Vogels Approximation MethodVogel's Approximation method is based on penalties and penalty is based on the difference between two least cost cells among rows and columns. Here we calculate the penalty of each row and columns and then select the that row or column which has got the highest penalty. In the corresponding row or column select the cost cell having least value. Then allocate maximum possible units to the selected cost cell and eliminate the row or column in which the supply is exhausted or demand is satisfied. Repeat the above steps until all the supplies and demands are satisfied.
