Exercise4 & 6 (Solution)

Fall 2023 Page 1 MIE1715H: Life Cycle Engineering Exercise 4: Due November 1, 2023 Question 1: For the typical text book SLCA performed in Exercise 3, the resulting matrix is shown below. Environmental Concerns Life Stage Material Choice Energy Use Residue Manufacture 0 1 1 Use 4 3 3 Recycling 2 0 2 The stakeholder wants the matrix to be updated to put half of the total score come from Residue in environmental concerns and half of the total score come from Manufacturing in the life stage. All the other elements have the same weight. Calculate the weighting factor for each element of the SLCA matrix, then calculate the new score for each element (show both the weight and new score). At the end, show the final weighted SLCA matrix on a target plot. Solution: The Use row, Recycling row, Material Choice column, and Energy Use column can maximum have a score of 9 each. Residue column and Manufacture row each can have a maximum score of 18. Therefore single weighted matrix will be (  i,j ) 5 . 1 18 3 4 75 . 0 9 3 4 =  =   =  =   y y x x Environmental Concerns Life Stage Material Choice Energy Use Residue

Fall 2023 Page 2 Manufacture 1.5 1.5 1.5 Use 0.75 0.75 0.75 Recycling 0.75 0.75 0.75 Environmental Concerns Life Stage Material Choice Energy Use Residue Manufacture 0.75 0.75 1.5 Use 0.75 0.75 1.5 Recycling 0.75 0.75 1.5 And the double weighted matrix would be (  i,j x  I,j ) Environmental Concerns Life Stage Material Choice Energy Use Residue Manufacture 1.125 1.125 2.25 Use 0.5625 0.5625 1.125 Recycling 0.5625 0.5625 1.125 And new matrix values would be Environmental Concerns Life Stage Material Choice Energy Use Residue Manufacture 0 1.125 2.25 Use 2.25 1.6875 3.375

Fall 2023 Page 1 MIE1715H: Life Cycle Engineering Exercise 6: Due: November 29, 2023 For the shape below, define the shape attributes. The holes on the top-left of the shape are closed at the bottom. Figure: A refrigerator compressor line clip. Solution: Depressions Yes Uniform Wall Yes Uniform Cross Section Yes Axis of Rotation No Regular Cross Section No Captured Cavity Yes Enclosed Cavity No No Draft Yes