Thursday, 13 October 2016

OR(Operations Research) | Linear programming | Assumptions | Applications

  Linear Programming

The word Linear Programming consist of two words

Linear This word is used to show the relationship between decision variables which are directly proportional. For example if we increase the production of product, it will proportionate increase the profit, this is called a linear relationship.
Programming It implies the planning of activities in such a way that the activities with available resources yield optimal results .

This Linear Programming states the  planning of decision variables which are directly proportional to achieve desired optimal results.
Or
Linear Programming involves the planning of activities to obtain an optimum result.

Linear Programming is the analysis of problems in which a linear function  of a number of variables is to be maximized (or minimized) when those variables are subject to a number of restraints in the form of linear inequalities”

Assumptions of Linear Programming

Linearity or proportionality A basic assumption of Linear Programming is that there exists proportionality in the objective function and the constraints. It implies that if a product gives a profit of Rs 25 the profit earned from the sale of 10 such products will be Rs 250.

Finite Choice Another assumption of a Linear Programming is that a limited number of choices are available to decision maker and the decision variable do not have negative values. This assumption is a realistic one, as it is not possible to produce or use negative quantities

Additivity It means that if m1 minutes are required to produce a product p1 on machine A and m2 minutes are required to produce a product p2, the total time required to make product p1 and p2 on machine A is m1+m2 minutes. This however, may not happen because of the change over time from product p1 to p2. Similarly the total profit is determined y the sum of profit is calculated by each of the products separately

Certainty A Linear Programming model also assumes that the various parameters, such as coefficients of the constraints, objective function coefficients and resources values are known certainty and they do not change with the passage of time. So, availability of materials, labour etc. the cost or profit per unit of the product, market demand of the product are assumed to be known certainly

Continuity One more assumption Linear programming is that the decision variables are continuous. It implies, combinations output with fractional values, in the context of production problems are possible.

Applications

Product Mix Linear programming helps in determining the quantity of different products to be manufactured knowing the marginal contribution of each product and amount of available resources used by each product

Transportation  problem Transportation n problems are faced by business organization which have number of availability centres (plants, warehouse etc.) with gives capacities which feed number of requirements cemtres (warehouse, markers etc.) with given requirements.

Blending problem This type of problem is faced by the chemical, food and petroleum industry etc. while deciding production of a product which can be made from a variety of available raw materials of different composition and prices.

Media selection LP has also been used in advertising firld as a decision aid in selecting the effective media. Media helps the marketing managers in allocation a fixed budget across various advertising media like newspapers, magazines, radio and television etc.

Diet problem it involves determination of combination of different nutrients such as proteins, vitamins, carbohydrates etc. for different foods to satisfy the minimum daily nutritional requirements at the minimum cost and minimizes the cost of raising live-stock.

Travelling salesman’s problem The problem of finding the shortest route for a salesman starting from a given city, visiting each of the specified cities, and returning to the original point of departure can be handled by the assignment technique of  linear programming.

Capital investment This type of problem arises because of the different ways in which a fixed amount of capital can be allocated to a number of activities. The total return depends upon the manner in which the allocation is made. This , the objective may  be to find that allocation which maximizes the total return








No comments:

Post a Comment