# Sutdent

Topics: Waste management, Recycling, Biodegradable waste Pages: 14 (3131 words) Published: April 20, 2013

SECTION 1- Logistics Decisions at VXL automotive1
Exhibition 11
Exhibition 26
Exhibition 39
Section 2- Sheffield City Council Waste Management10
Section 3- Reflection question15

SECTION 1- Logistics Decisions at VXL automotive

Exhibition 1

1. Identify and explain all the constraints

In this report, city model is called as “C” and family model is simplified as “F”.

Owing to the head of Logistic and Supply Production Planning team has mentioned that the figure of car production in February should not over the forecast of March 2013 multiplied by 1.06 (corrective factor). Meanwhile, the figure must not lower than number in February.

3514 ≤ C ≤ 3784

Also, the amount of the Family model should higher than 1200.

1200 ≤ F

In terms of passenger doors:

City model has 2 doors while family mode has 4 doors and the contract indicates that the minimum number is 6000 doors for both figures whist the maximum is 18000.

6000 ≤ 2C+4F ≤ 18000

Turning to the assemble time:

Family model needs 20 hours to assemble a car whist the city one takes 15. The total worker is 650 people and each people work 40 hours per week, also this number should turn into monthly which means the result multiply 4. The outcome multiplies the absenteeism that is 4%.

Total work time:

650*40*4*(1-4%)= 99840

20F/ car family car
15C/car city car

20F + 15C ≤ 99840

The profit margin of family model is higher 15% than city one, so the formula can be assumed as F*115%

Max profit margin =F+C

Max profit margin= F115%+C

2. Solve it by using the graphical method

Chart 1
Chart 1

So the optimal product mix is: F = 2154, C = 3784

Max profit is 2154*115%+3784= 6261

3. Check the results by using the Excel Solver:

Chart 2
Chart 2

After predicted the De-seasonal series, the outcome can be list as below

De-seasonal series|
49| 3540|
50| 3553|
51| 3565|
52| 3578|
53| 3590|
54| 3603|
55| 3615|

The De-seasonal series multiply the seasonal indices can predict the seasonal series:

Seasonal series|
JAN| 49| 3327|
FEB| 50| 3514|
MAR| 51| 3570|
| 52| 3674|
| 53| 4021|
| 54| 4340|
| 55| 3412|

By following this, the figure of February and March can be used as the constraints to find the answer. The constraints can be found in the list below:
1| F| ≥| 1200|
2| C| ≥| 3514|
3| C| ≤| 3784|
4| 4F+2C| ≤| 18000|
5| 4F+2C| ≥| 6000|
6| 20F+15C| ≤| 99840|
7| F.C| ≥| 0|
8| F.C| 　| Integers|

By using the solver, the optimal product mix can be found as below:

The optimal product mix|
F| C|
2154| 3784|

As the graph shown below, the answer is the same with the graphical method:

MAX PROFIT
MARGIN|
6261|

4. Identify the most stringent constrains and give some advices to VXL to potentially increase the monthly output and/or maximize the efficiency of the operations.

The most important factor to the output of cars is the total assemble time. If the total work time rises, it will influence the amount of cars and the max profit margin. In this question, assuming the absenteeism rate falls to 2% and identifies the different between the original one and the assuming one.

Under the 4% absenteeism rate

AVAILABLE TIME| The optimal product mix| MAX PROFIT
MARGIN|
| F| C| |
99840| 2154| 3784| 6261|

Under the 2% absenteeism rate

AVAILABLE TIME| The optimal product mix| MAX PROFIT
MARGIN|
| F| C| |
101920| 2258| 3784| 6381|

The second table shows the max profit margin increase to 6381 from 6261 and the figure of family model rise around a hundred cars from 2154 if the available time rises to 101920. So it can be proved that the total work time has a tremendous effect to business profit. 5. The outcome of process improvement.

If some process can be modified, the...