For the Assignment Below Turn In

Zimmer CSCI 270 Spring 042

Assignment #3 Due Date: March 31, 2004

Remember you are to complete the assignment on your own, unless otherwise stated. Make sure you follow the Assignment Guidelines you received at the beginning of the semester.

For the assignment below turn in:  Complete the questions below – write/type on one side of the page only, make sure your work is legible. Attach this assignment sheet as the cover sheet placing your name, csci270-001, and A#3 on three lines in the upper right corner. In the upper left corner staple the purple cover to your answers.

Complete the following: 1. List and define three major search strategies 2. Define blind searching and list an advantage and a disadvantage of this search technique. 3. Define heuristic searching and give an advantage and a disadvantage of this search technique. 4. Define forward chaining and give an example of a problem that would use it. 5. Define backward chaining and give an example of a problem that would use it. 6. Study the search tree below. The number associated with each node indicates the profit associated with that node. The goal is to find a node with the profit value of twenty or higher.

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7. Apply the best-first approach to the traveling sales person problem below. The number on each arc indicates the distance. Start from city 5.

8. Your mission is to process three jobs on one machine (one after the other) with the least possible change-over time. The machine is currently empty. The table below shows you how long it takes, in minutes, to change from one job (or from empty) to another. Draw the entire search tree using empty as the starting position. Write the sequence using the best-first approach.

To Job From Job 1 2 3 Empty 25 20 30 1 0 35 20 2 50 0 20 3 45 10 0

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9. The table below shows a doctor’s patients who are waiting for their appointments, and the corresponding projected treatment times. The doctor wishes to schedule the patients to minimize average wait time. Formulate two heuristic rules (use English) and compare them with taking the patients in the order given (A, B, C, …, F).

Patient Treatment Time in hours A 1.0 B .2 C 2.0 D 1.5 E .1 F .7