Operation Research
Essay by msanagowdar • March 6, 2016 • Coursework • 618 Words (3 Pages) • 939 Views
Problem #2.1 (Integer Linear Program): Formulate the following nurse-staffing problems as integer linear programs, i.e., linear programs with further integer constraints on the decision variables. Solve them using the Excel Solver
Part (a): Assume that the hospital hires only full-time nurses, and the nurses begin service at the start of a period and work for 8 consecutive hours. The hospital wants to determine a work schedule for the typical day that requires the least number of nurses while satisfying the requirements. Formulate this problem as an integer linear program. First, ignore the integer requirements. Then, impose the integer requirements and compare the difference.
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2.1 SENSITIVITY REPORT[pic 2]
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ANSWER REPORT 2.1 PART B
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SENSITIVITY 2.1 PART B
): Now assume that the hospital also hires temporary nurses who work four-hour shifts, i.e., part-time, and begin service at the start of a period. Also assume that a full-time nurse costs $20 per hour while a temporary (part-time) nurse costs $14 per hour, and that the cost does not vary with shift. Formulate an integer linear program to determine how the hospital can minimize the total cost of nurse staffing for the typical day while satisfying the requirements. First, ignore the integer requirements. Then, impose the integer requirements and compare the difference.
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SENSITIVITY 2.1 PART C
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ANSWER REPORT 2.1[pic 8]
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ANSWER REPORT 2.1 PART C
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PROB 2.4
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PROB 2.5
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EQUATIONS:
PROB 2.5
Constraints: |
C1 + C2 <= 15000 |
C1 <= 10000 |
C2 <= 10000 |
H >= 3000 |
J >= 3000 |
G >= 3000 |
D1.CR + D2.CR <= 5000 |
0.6 * C1 + 0.4 * C2 - NG - NJ = 0 |
0.3 * C1 + 0.2 * C2 - D1.CR - D1.H = 0 |
0.1 * C1 + 0.4 * C2 - D2.CR - D2.H = 0 |
0.8 * D1.CR + 0.7 * D2.CR - D2.CR1 - D1.CR1 = 0 |
0.2 * D1.CR + 0.3 * D2.CR - D2.CR2 - D1.CR2 = 0 |
H - D1.H - D2.H = 0 |
J - NJ - D1.CR1 - D1.CR2 = 0 |
G - NG - D2.CR1 - D2.CR2 = 0 |
(-8.5) * G + 8 * NG + 9 * D2.CR1 + 6 * D2.CR2 >= 0 |
(-7) * J + 8 * NJ + 9 * D1.CR1 + 6 * D1.CR2 >= 0 |
(-4.5) * H + 4 * D1.H + 5 * D2.H >=0 |
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