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What is Operation Research. Tools and Techniques used in Operation Research.

•6 j'aime•187 vues

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What is Operation Research. Tools and Techniques used in Operation Research.

- 1. AN OVERVIEW ON OPERATION RESEARCH AND TOOLS AND TECHNIQUES USED - ADITYA JHUNJHUNWALA,17001 The British/Europeans refer to "operational research", the Americans to "operations research" - but both are often shortened to just "OR" (which is the term we will use). Another term, which is used, for this field is "management science" ("MS"). The Americans sometimes combine the terms OR and MS together and say "OR/MS" or "ORMS". Yet other terms sometimes used are "industrial engineering" ("IE"), "decision science" ("DS"), and “problem solving”. In recent years there has been a move towards a standardization upon a single term for the field, namely the term "OR". “Operations Research (Management Science) is a scientific approach to decision making that seeks to best design and operate a system, usually under conditions requiring the allocation of scarce resources.” A system is an organization of interdependent components that work together to accomplish the goal of the system. HISTORY OF OPERATION RESEARCH The name operations investigate advanced in the year 1940. Amid World War 2, a group of researcher (Blackett's Circus) in UK connected logical strategies to examine military operations to win the war and the procedures consequently created was named as operation explore. As a formal train, operations inquire about started from the endeavours of armed force guides at the season of World War II. In the years following the war, the techniques began to be utilized widely to issues in business, industry and society. As far back as at that point, OR has formed into a subject as often as possible utilized in ventures including petrochemicals, coordination’s, aircrafts, fund, government, and so on. Along these lines, the Operational Research started amid World War II in incredible Britain with the foundation of gatherings of researchers to break down the vital and strategic issues related with military operations. The point was to find the most proficient utilization of constrained military assets by the use of quantitative systems. India was among the couple of countries which started using O.R. In 1949, the primary Operational Research unit was built up at Hyderabad which was named Regional Research Laboratory found. In the meantime an extra unit was propelled in Defence Science Laboratory to settle the Stores, Purchase and Planning Problems. In 1953 at Calcutta, an O.R. unit was built up in Indian Statistical Institute. The goal was to utilize O.R. strategies in National Planning and Survey. In 1955, Operations Research Society of India was made, which is among the main individuals from International Federation of Operations Research social orders. Today, the use of O.R. systems have spread out from armed force to an extensive variety of offices at all levels.
- 2. THE METHODOLOGY OF OR When OR is used to solve a problem of an organization, the following seven-step procedure should be followed: Step 1. Formulate the Problem OR analyst first defines the organization's problem - Defining the problem includes specifying the organization's objectives and the parts of the organization (or system) that must be studied before the problem can be solved. Step 2. Observe the System - The analyst collects data to estimate the values of parameters that affect the organization's problem. These estimates are used to develop (in Step 3) and evaluate (in Step 4) a mathematical model of the organization's problem. Step 3. Formulate a Mathematical Model of the Problem - The analyst, then, develops a mathematical model (in other words an idealized representation) of the problem. In this class, we describe many mathematical techniques that can be used to model systems. Step 4. Verify the Model and Use the Model for Prediction - The analyst now tries to determine if the mathematical model developed in Step 3 is an accurate representation of reality. To determine how well the model fits reality, one determines how valid the model is for the current situation. Step 5. Select a Suitable Alternative Given a model and a set of alternatives - The analyst chooses the alternative (if there is one) that best meets the organization's objectives. Sometimes the set of alternatives is subject to certain restrictions and constraints. In many situations, the best alternative may be impossible or too costly to determine. Step 6. Present the Results and Conclusions of the Study - In this step, the analyst presents the model and the recommendations from Step 5 to the decision-making individual or group. In some situations, one might present several alternatives and let the organization choose the decision maker(s) choose the one that best meets her/his/their needs. After presenting the results of the OR study to the decision maker(s), the analyst may find that s/he does not (or they do not) approve of the recommendations. This may result from incorrect definition of the problem on hand or from failure to involve decision maker(s) from the start of the project. In this case, the analyst should return to Step 1, 2, or 3. Step 7. Implement and Evaluate Recommendation - If the decision maker(s) has accepted the study, the analyst aids in implementing the recommendations. The system must be constantly monitored (and updated dynamically as the environment changes) to ensure that the recommendations are enabling decision maker(s) to meet her/his/their objectives. OPERATIONAL RESEARCH TOOLS AND TECHNIQUES Operations Research utilizes any appropriate apparatuses or systems accessible. The regular every now and again utilized devices/strategies are scientific systems, cost investigation, electronic calculation. However, operations analysts given unique significance to the improvement and the utilization of systems like direct programming, amusement hypothesis, choice hypothesis, lining hypothesis, stock models and recreation. Notwithstanding the above strategies, some other basic apparatuses are non-straight programming, whole number programming, dynamic programming, sequencing hypothesis, Markov process, arrange planning (PERT/CPM), emblematic Model, data hypothesis, and esteem hypothesis. There is numerous different Operations Research instruments/procedures likewise exists.
- 3. The concise clarifications of a portion of the above systems/instruments are as per the following: Linear Programming: This is a constrained optimization technique, which optimize some criterion within some constraints. In Linear programming the objective function (profit, loss or return on investment) and constraints are linear. There are different methods available to solve linear programming. Game Theory: This is used for making decisions under conflicting situations where there are one or more players/opponents. In this the motive of the players are dichotomized. The success of one player tends to be at the cost of other players and hence they are in conflict. Decision Theory: Decision theory is concerned with making decisions under conditions of complete certainty about the future outcomes and under conditions such that we can make some probability about what will happen in future. Queuing Theory: Choose the solution to be used. ‘Sell’ the decision to operating managers; get their understanding and cooperation. Manager and O.R. Specialist This is used in situations where the queue is formed (for example customers waiting for service, aircrafts waiting for landing, jobs waiting for processing in the computer system, etc). The objective here is minimizing the cost of waiting without increasing the cost of servicing. Inventory Models: Inventory model make a decisions that minimize total inventory cost. This model successfully reduces the total cost of purchasing, carrying, and out of stock inventory. Simulation: Simulation is a procedure that studies a problem by creating a model of the process involved in the problem and then through a series of organized trials and error solutions attempt to determine the best solution. Some times this is a difficult/time consuming procedure. Simulation is used when actual experimentation is not feasible or solution of model is not possible. Non-linear Programming: This is used when the objective function and the constraints are not linear in nature. Linear relationships may be applied to approximate non-linear constraints but limited to some range, because approximation becomes poorer as the range is extended. Thus, the non-linear programming is used to determine the approximation in which a solution lies and then the solution is obtained using linear methods. Dynamic Programming: Dynamic programming is a method of analysing multistage decision processes. In this each elementary decision depends on those preceding decisions and as well as external factors. Integer Programming: If one or more variables of the problem take integral values only then dynamic programming method is used. For example number or motor in an organization, number of passenger in an aircraft, number of generators in a power generating plant, etc.
- 4. APPLICATIONS OF OPERATIONS RESEARCH Today, almost all fields of business and government utilizing the benefits of Operations Research. There are voluminous of applications of Operations Research. Although it is not feasible to cover all applications of O.R. in brief. The following are the abbreviated set of typical operations research applications to show how widely these techniques are used today: Accounting: Assigning audit teams effectively, Credit policy analysis, Cash flow planning, Developing standard costs, Establishing costs for by products, Planning of delinquent account strategy Construction: Project scheduling, monitoring and control, Determination of proper work force, Deployment of work force, Allocation of resources to projects Facilities Planning: Factory location and size decision, Estimation of number of facilities required, Hospital planning, International logistic system design, Transportation loading and unloading, Warehouse location decision. Finance: Building cash management models, Allocating capital among various alternatives, Building financial planning models, Investment analysis, Portfolio analysis, Dividend policy making. Manufacturing: Inventory control, Marketing balance projection, Production scheduling, Production smoothing. Marketing: Advertising budget allocation, Product introduction timing, Selection of Product mix, Deciding most effective packaging alternative. Organizational Behaviour / Human Resources: Personnel planning, Recruitment of employees, Skill balancing, Training program scheduling, Designing organizational structure more effectively. Purchasing: Optimal buying, optimal reordering, Materials transfer.
- 5. LIMITATIONS OF OPERATIONS RESEARCH Operations Research has number of applications; similarly it also has certain limitations. These limitations are mostly related to the model building and money and time factors problems involved in its application. Some of them are as given below: I.Distance between O.R. specialist and Manager Operations Researchers job needs a mathematician or statistician, who might not be aware of the business problems. Similarly, a manager is unable to understand the complex nature of Operations Research. Thus there is a big gap between the two personnel. II.Magnitude of Calculations The aim of the O.R. is to find out optimal solution taking into consideration all the factors. In this modern world these factors are enormous and expressing them in quantitative model and establishing relationships among these require voluminous calculations, which can be handled only by machines. III.Money and Time Costs The basic data are subjected to frequent changes, incorporating these changes into the operations research models is very expensive. However, a fairly good solution at present may be more desirable than a perfect operations research solution available in future or after some time.