A constrained version of the Shortest Path Tour Problem is addressed.Its theoretical properties are analyzed: the problem belongs to the NP-complete class.A Branch & Bound (B&B) and a GRASP are proposed for its solution.The B&B can be used to solve only small size instances.The GRASP is ...
Given a directed graph with non-negative arc lengths, the Constrained Shortest Path Tour Problem ( ) is aimed at finding a shortest path from a single-origin to a single-destination, such that a sequence of disjoint and possibly different-sized node subsets are crossed in a given fixed order...
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2224 题意:平面上有n个点,问去的路只能从左到右,回的路只能从右到左的,且来回必须经过所有点的最小路径; dp[i][j] 表示以j为起点,1为拐点 ,i为终点的最短路; j < i-1 时,那么i-1这个点在来的路径上 必然等于dp[i-1][j] + dis[i-...
We consider the MaximumInternalSpanningTree problem which is to find a spanning tree of a given graph with a maximum number of non-leaf nodes. From an opti... G Salamon - Springer Berlin Heidelberg 被引量: 26发表: 2007年 Polynomial Time Approximation Schemes for the Constrained Minimum Spannin...
Constrained Benchmark Function from mealpy import FloatVar, SMA import numpy as np ## Link: https://onlinelibrary.wiley.com/doi/pdf/10.1002/9781119136507.app2 def objective_function(solution): def g1(x): return 2*x[0] + 2*x[1] + x[9] + x[10] - 10 def g2(x): return 2 * ...
We formulate the problem as a set partitioning model with a probabilistic constraint on the global success probability of the route plan. We solve the VRPTW-ST by a branch-price-and-cut algorithm. The results show that our method is effective, and that a stochastic chance-constrained model ...
For an algorithm to be termed “efficient”, its execution time must be constrained by a polynomial function of the input size. It was realised early on that not all issues could be handled thus rapidly, but it was difficult to determine which ones could and which couldn’t. Some so-calle...
They set a logical problem (devising the shortest route for a travelling salesman visiting various cities). Three groups were involved: one where subjects acted independently; another where they saw the solutions posted by team members at every stage; and a third where they were kept informed ...
This problem can be categorized as the Traveling Salesman Problem (TSP), which is a problem where a salesman has to visit all areas where each area has only been visited once and must return to the hometown. The purpose of this study is to determine the shortest time in submitting orders,...
Here, the popularly applied Double Constrained Gravity (DCG) model presented in Figure 1 was adopted. Table 3 shows the estimation results of this DCG sub-model. It can be found that the parameter representing travel resistance gives a logical sign and statistically significant value. Moreover, ...