This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: AMS 341 (Spring, 2010) Exam 2 - Solution notes Estie Arkin Mean 73.925, median 76, top quartile 87, high 99, low 12. 1. (10 points) I am planning a vacation once the spring semester is over. There are many tasks that have to be completed before I can go. Fortunately, I can get help from family and friends. The following are the tasks that would have to be undertaken before the vacation: Task Predecessors Time (hours) A- 2 B- 3 C A 1 D B 8 E B,C 7 F D,E 5 (a). Draw a project network. 1 2 3 4 5 6 A-2 B-3 C-1 dummy-0 D-8 E-7 F-5 Common mistakes: several start nodes, undirected edges, wrong predecessors. (b). What is my critical path? You may find the path either by computing the total float for each node, or by inspection. (Your answer should be a list all critical activities.) Tasks B,D,F (or nodes 1,3,5,6). 2. (10 points) Consider the following (minimum) Balanced Transportation problem: Find an initial BFS for the problem using the min cost method: 1 100 100 100 75 75 125 25 1 2 3 4 5 6 7 8 9 1 1 25 75 100 25 75 Common mistake: not enough basic variables. You should have 4 + 3 − 1 = 6. 3. (15 points) Plans are being made for the energy systems for a new building. The three possible sources of energy are electricity, natural gas and a solar heating unit. The energy requirements are: 20 units of electricity, 10 units for water heating and 30 units for space heating. The size of the roof limits the solar heater to 30 units. There is no limit on the amount of electricity or natural gas bought. Electricity needs can only be met by buying electricity at a cost of $ 50 per unit. Other energy needs can be met by any sources with the following unit costs: Electricity Natural Gas Solar heater Water heating $ 90 $ 60 $ 30 Space heating $ 80 $ 50 $ 40 Formulate a Balanced Transportation Problem to minimize the...
View Full Document
This note was uploaded on 05/28/2011 for the course AMS 341 taught by Professor Arkin,e during the Spring '08 term at SUNY Stony Brook.
- Spring '08