These lecture notes are based on the subject Global Supply Chain Management of 2015-2016.

Lecture 1

Lecture 1 focuses mainly on:

• simulation
• Deterministic performance estimation

Both are approaches to to analyze and design a process.

There are different criteria to determine if a design is good or bad. A design is made in a flow diagram. These criteria are used to analyze the design. The main goal of analyzing a design, is to attain contiguous improvement.

Differences :

• Deterministic: easy and fast, but rough overview
• Simulation: long and complex, but gives a better and more specific outcome.

Simulation:

Simulation experiments many times, and tries to duplicate a real environment into its model. Mathematically, a real world situation is imaged. After wards, a conclusion is stated, and a company will decide if it will adapt to this conclusion.

Main advantages:

• It is used in difficult situations
• There is no investment needed
• Uncertainty is incorporated, so it is very functional in real life
• More solutions are shown

Main disadvantages:

• Analyzing and interpreting outcomes is difficult
• High computation time
• Difficult to make
• Value of the result is overestimated many times

Most of the large companies use this method.

To be able to understand the following topic, one must understand the following things:

• Throughput time
• Work-in-progress
• Bottleneck
• Throughput/departure rate
• Utilization & efficiency

Deterministic performance analysis:

There is a distinction between deterministic and stochastic determination time

• Deterministic: everything is known in advance
• Stochastic: things might change, not everything is known in advance

In order to know the deterministic throughput time, you must know the time between the point that the customer/product enters the system, and the costumer/product is ready. Always take the average time that is needed.

Design & effective capacity:

• Design: Theoretical maximum output
• Effective: capacity that can be expected given the circumstances

We distinct serial and parallel processing

• Serial: steps follow each other up
• Parallel: steps are done at the same time.

Parallel servers:

• One server can only serve one customer
• Other servers serve other customers simultaneous

You must be able to find the bottleneck in a system. Bottleneck = the part of a design that makes the rest of the design slower. It is similar to the statement: a design is a strong as its weakest link.

Departure rate = number of customers/products that leave the system per hour. Depends on the bottleneck of the system.

Utilization rate & efficiency:

• Utilization rate = total operating time/ total time = actual output/ design capacity
• Utilization efficiency = actual output/ effective capacity

Effective capacity = the.....read more