Rules for Ties

In Linear Programming, in choosing the key column and key row, whenever there is a tie between two or more numbers, the following rules may be followed.
1. If there is a tie between two or more numbers in the index row, select the column farthest to the left as the key column.
2. If there is a tie between two or more smallest positive ratios in the ratio column, select the row nearest to t6he top as key row.

Nominal Group Technique

Nominal group technique is a participatory approach for finding fact, identifying problems and strengths, generating ideas and evaluating progress. It is based on assumption of work independently and then, combines ideas. In this technique, each individual member are presented with a problem and each member is responsible for developing ideas for situation individually and independently. All these ideas are shared with each other in a prescribed format for suggestion and classification. At last, group members choose the best alternative by secret ballot. This process is called nominal because all members work independently and are considered as a part of group in name only.

Service Mechanism

The service mechanism is concerned with the manner in which customers are serviced and leave the service system. It refers to arrangement of service facilities and service time distribution.

Surplus Variables

If the constraints of given LP (Linear Programming) problem are greater than or equal to type, then non-negative variables are subtracted from left hand sides of greater than or equal to constraints to convert them into equations. Such non negative variables are called surplus variables.