Linear Programming Algorithm

2421 Words10 Pages

1.INTRODUCTION The traffic control requires optimized route control in case of train schedule disruptions, by automatic route setting and real-time schedule alteration. The basic functions are : Route tracking Traffic control Priority decision functions The basic purpose of train scheduling in a railway network is to adjust train service provisions according to the traffic demands, limitations imposed by physical network and the maintenance and renewal necessities. It also involves locomotive stock and train crew planning. In engaged networks, there are lots of stations with a few hundred trains per day while the track often contains cumbersome layouts, multiple intertwined in-line, out-line, one-way/two-way through-stand. On the other …show more content…

Hybrid optimization algorithm for solving non-convex NLP/MINLP problems with constraints 1.1 BASIC CONCEPTS (a) LINEAR PROGRAMMING: Linear programming (LP; also called linear optimization) is a method to obtain the best result (such as maximum profit or lowest cost) whose requirements and constraints are depicted by linear relationships, in a mathematical model. Linear programming is a special sub-case of mathematical programming (mathematical optimization). On a more clear note, linear programming is a method for the optimization of a linear objective function, subject to linear equality and linear inequality constraints[47]. Its best domain of region is a convex polytope, which is a set of intersection of finitely many half spaces, each of which is constituted of a linear inequality. Its chief function is a real-valued affine (linear) function defined on this polyhedron. If such a point exists where this function has the smallest or the largest value, then a linear programming algorithm is used to find the value. Linear programs are problems that can be expressed in canonical form as Maximize c^Ty Subject to Ky ≤ b and y ≥ 0 where y represents the vector of variables (to be determined), c and b are vectors of (known) …show more content…

A simple mathematical formula is followed to move the particles around in the search space. When an optimized space is found, the last viewed space is un-recorded and the new position is stored. This leads to utilization of memory. This improvisation of positions leads to a better direction of movement. This process is iterated with the hope that a better solution will be found, though there is no Cen percent guarantee to it. Formally, let f: ℝn → ℝ be the cost function which must be minimized. The function takes a candidate solution as argument in the form of a vector of real numbers and produces a real number as output which indicates the objective function value of the given candidate solution. The gradient of f is not known. The goal is to find a solution a for which f(a) ≤ f(b) for all b in the search-space, which would mean a is the global minimum. Maximization can be performed by considering the function h = -f instead. Let S be the number of particles in the swarm, each having a position xi ∈ ℝn in the search-space and a velocity vi ∈ ℝn. Let pi be the best known position of particle i and let g be the best known position of the entire swarm. A basic PSO algorithm is

More about Linear Programming Algorithm

Open Document