1. Problem Solving

2. ChE 201 Section 2 PROBLEM SOLVING What is PS? PS is to plan how to solve the problem effectively and efficiently Is it important ? examples of ill-defined problems clarify its importance (see handouts)

3. There are 2 types of problems: 1. Closed-ended 2. Open-ended -For closed –ended problems Some PS techniques are:  The Polya Technique Define the problem Plan the solution Carry out the plan Look back (review)

4. -For closed –ended problems Some PS techniques are: 1.Define the problem 2.Plan the solution 3.Carry out the plan 4.Look back (review) 1- The Polya Technique

5. To evaluate (review or look back) the solution: you need to look back and make sure that :  all of the criteria in the problem statement were fulfilled  none of the constraints or assumptions were violated  the problem has really been solved  the solution is the best one  the solution is innovative, new, novel.  the solution is ethical, safe, reasonable and possible

6. To define the problem :  Collect and analyze information and data  Find out where the problem came from  Restate the problem if necessary

7. 1. Define the problem 2. Generate alternative solutions 3. Decide on a plan to solve 4. Carry out the plan Evaluate 5. Evaluate the outcome (review) -For closed –ended problems 2- The Fogler and LeBlanc Technique

8. 1. Define the problem 2. Explore the problem 3. Plan the solution 4. Act 5. Reflect (review) -For closed –ended problems 3- The McMaster Technique

9. To explore the problem:  Review and write down key features  Draw a diagram of flows, variables  State what the problem is  Enter known data into diagram  Enter symbols for unknowns on diagram  List relevant laws, principles (equations)  Employ suitable notation  Fix the system  List assumptions  Locate missing information  Pick a basis

10. 1. Analysis of the problem 2. Decision procedure 3. Identification of future pitfalls associated with the solution -For closed –ended problems 4- The Kepner-Tregve Technique

11. 1. Understand the problem 2. Formulate the options for the solution 3. Consider the constraints 4. Execute the selected PS strategy 5. Evaluate the procedure and results -For open –ended problems

12. Computer –Based Tools Sources of Data