49928: Design Optimisation for Manufacturing

Assignment 2: Discrete Optimisation

Due: 9:00 am Monday 15/10/2018

? Solve the following two problems with both exhaustive enumeration and branch and bound

? The assignment is worth 15 marks in total (15% of your final mark for the subject)

? Exhaustive enumeration is worth 2.5 marks for each problem, branch and bound is worth 5 marks for each problem.

? Problem 1 is a mixed integer linear optimisation problem (the problem has both discrete and continuous variables). Do not use intlinprog (from MATLAB) to solve this problem, for exhaustive enumeration solve it by enumerating through the discrete variables and then use linprog to find the continuous variables. For branch and bound use linprog or Excel Solver to find the partial solutions.

? Problem 2 is a discrete nonlinear optimisation problem. For branch and bound use fmincon or Excel Solver to find the partial solutions.

? Write a report:

? Describe the process of finding the solution: how many evaluations were needed for exhaustive enumeration? What path did the search take for branch and bound? How many partial and full evaluations were needed for branch and bound?

? Include your MATLAB code for exhaustive enumeration

? Include any code or an image of any spreadsheets used for branch and bound

? Draw the trees for branch and bound. For each node state:

¦ Which variables are constrained

¦ The partial or full solution

¦ Whether or not the solution is feasible

¦ Whether or not the node has been pruned

Problem 1 (8 marks)

Minimise:

f = 4x1 + 5x2 + 3x3 + 6x4 + 4x5 + 5x6 + 7x7

Subject to:

g1 = 4x1 + 3x2 + 6x3 + 5x4 + x5 + x6 + 3x7 = 50 g2 = 7x1 + 2x2 + 2x3 + 6x4 + 3x7 = 70 g3 = 6x1 + 5x2 + 3x3 + 3x4 + x5 + 8x6 + x7 = 40

x1, x2, x3, x4 ? {1, 2, 3, 4} x5, x6, x7 = 0

Problem 2 (7 marks)

An I-beam is shown in the figure to the right. Given the following equations and constraints, develop a mathematical model and find the dimensions of a beam with a minimal cross sectional area.

Cross sectional area: A = x1x2 + 2x3x4 - 2x2x4 cm2

Section modulus: S = x1(x3x4 + x16x2) cm3

Bending moment: M = 400 kNm

Axial force: P = 130 kN

Bending stress: sB = 100S0M MPa

Axial stress: sP = MPa

Stress constraint: sB + sP - 250 = 0 MPa

Buckling constraint:

And subject to the following constraints on plate thickness and width:

x1 : 37, 39, 41 x2 : 1.1, 1.2, 1.3 x3 : 30, 32, 34 x4 : 0.8, 1.0, 1.2

Assignment 2: Discrete Optimisation

Due: 9:00 am Monday 15/10/2018

? Solve the following two problems with both exhaustive enumeration and branch and bound

? The assignment is worth 15 marks in total (15% of your final mark for the subject)

? Exhaustive enumeration is worth 2.5 marks for each problem, branch and bound is worth 5 marks for each problem.

? Problem 1 is a mixed integer linear optimisation problem (the problem has both discrete and continuous variables). Do not use intlinprog (from MATLAB) to solve this problem, for exhaustive enumeration solve it by enumerating through the discrete variables and then use linprog to find the continuous variables. For branch and bound use linprog or Excel Solver to find the partial solutions.

? Problem 2 is a discrete nonlinear optimisation problem. For branch and bound use fmincon or Excel Solver to find the partial solutions.

? Write a report:

? Describe the process of finding the solution: how many evaluations were needed for exhaustive enumeration? What path did the search take for branch and bound? How many partial and full evaluations were needed for branch and bound?

? Include your MATLAB code for exhaustive enumeration

? Include any code or an image of any spreadsheets used for branch and bound

? Draw the trees for branch and bound. For each node state:

¦ Which variables are constrained

¦ The partial or full solution

¦ Whether or not the solution is feasible

¦ Whether or not the node has been pruned

Problem 1 (8 marks)

Minimise:

f = 4x1 + 5x2 + 3x3 + 6x4 + 4x5 + 5x6 + 7x7

Subject to:

g1 = 4x1 + 3x2 + 6x3 + 5x4 + x5 + x6 + 3x7 = 50 g2 = 7x1 + 2x2 + 2x3 + 6x4 + 3x7 = 70 g3 = 6x1 + 5x2 + 3x3 + 3x4 + x5 + 8x6 + x7 = 40

x1, x2, x3, x4 ? {1, 2, 3, 4} x5, x6, x7 = 0

Problem 2 (7 marks)

An I-beam is shown in the figure to the right. Given the following equations and constraints, develop a mathematical model and find the dimensions of a beam with a minimal cross sectional area.

Cross sectional area: A = x1x2 + 2x3x4 - 2x2x4 cm2

Section modulus: S = x1(x3x4 + x16x2) cm3

Bending moment: M = 400 kNm

Axial force: P = 130 kN

Bending stress: sB = 100S0M MPa

Axial stress: sP = MPa

Stress constraint: sB + sP - 250 = 0 MPa

Buckling constraint:

And subject to the following constraints on plate thickness and width:

x1 : 37, 39, 41 x2 : 1.1, 1.2, 1.3 x3 : 30, 32, 34 x4 : 0.8, 1.0, 1.2

Ideas for the Impacts on Asset Management from the GFCWord count (500 word).Discussion boardWanted to use this as a general sharing space for starting point around the impacts on asset management Post...Business Concept Plan Identifying an opportunity is great! For example, before Uber became a global icon the idea of a technologically based journey service was just an embryonic idea by Garrett Camp and...Written assignment:Critical analysis of the literature1000 wordsWeighting: 30% Due Date:5 August, 2019AimThis assessment assists you in the understanding of clinical infectious diseases by demonstrating...Scenario InformationScenario Simulation - Council Truck FleetScenario Background - IntroductionIn this part of the course, students take on the role of Asset Manager in a “gaming” environment that is a...Class Challenge 1Hendrik du Toit (CEO Investec Asset Management) outlines the international context of financial asset management. Assuming that Hendrik is correct in his assessment for the world economy...Marking SheetUnit: Marketing for Managers Term:Assessment Task Number: AT3 Weighting: 35%Assessment Task Title: Marketing PlanStudent Name: Student Number:Academic Grading Criteria Marks Allocated Marks...Economics NF Assessment:Firms such as Uber, Airbnb, Foodora etc. are all part of what is known as the -sharing economy-, which is a generic term that describes economic and social activities that take...**Show All Questions**