Operations Research

151. __________ occurs when the number of occupied squares is less than the number of rows plus

1. Degeneracy
2. Infeasibility
3. Unboundedness
4. Unbalance
5. Redundancy

152. __________ or __________ are used to "balance" an assignment or transportation problem.

1. Destinations; sources
2. Units supplied; units demanded
3. Dummy rows; dummy columns
4. Large cost coefficients; small cost coefficients
5. Artificial cells; degenerate cells

153. A solution can be extracted from a model either by

1. Conducting experiments on it
2. Mathematical analysis
3. Both A and B
4. Diversified Techniques

154. An alternative optimal solution to a minimization transportation problem exists whenever opportunity cost corresponding to unused route of transportation is:

1. Positive & greater than zero
2. Positive with at least one equal to zero
3. Negative with at least one equal to zero
4. None of the above

155. Which of these statements about the stepping-stone method is best?

1. A dummy source and destination must be added if the number of rows plus columns minus 1 is not equal to the number of filled squares.
2. Only squares containing assigned shipments can be used to trace a path back to an empty square.
3. An improvement index that is a net positive means that the initial solution can be improved.
4. Only empty squares can be used to trace a path back to a square containing an assigned shipment

156. An assignment problem can be viewed as a special case of transportation problem in which the capacity from each source is __________ and the demand at each destination is __________.

1. 1; 1
2. Infinity; infinity
3. 0; 0
4. 1000; 1000
5. -1; -1

157. Both transportation and assignment problems are members of a category of LP problems called __________.

1. shipping problems
2. logistics problems
3. generalized flow problems
4. routing problems
5. network flow problems

158. Consider the given vectors: a(2,0), b(0,2), c(1,1), and d(0,3). Which of the following vectors are linearly independent?

1. a, b, and c are independent
2. a, b, and d are independent
3. a and c are independent
4. b and d are independent

159. Consider the linear equation
2 x1 + 3 x2 - 4 x3 + 5 x4 = 10
How many basic and non-basic variables are defined by this equation?

1. One variable is basic, three variables are non-basic
2. Two variables are basic, two variables are non-basic
3. Three variables are basic, one variable is non-basic
4. All four variables are basic

160. During an iteration while moving from one solution to the next, degeneracy may occur when

1. The closed path indicates a diagonal move
2. Two or more occupied cells are on the closed path but neither of them represents a corner of the path.
3. Two or more occupied cells on the closed path with minus sign are tied for lowest circled value
4. Either of the above