Question

Question 7: Short Answer Questions 1) What are Gantt chart and precedence network? Compare a Gantt chart and a precedence network. 2 What is a critical activit 3) What approaches do supermarkets used to reduce waiting time? 4) Explain Little's Law Formula: L AW 5) What information can be gleaned from a bill of materials? If you were asked to produce an item based solely on a copy of its BOM, what missing information would you need?

Answer 1

1) A Gantt chart is a type of bar chart that illustrates a project schedule, named after its inventor, Henry Gantt (1861–1919), who designed such a chart around the years 1910–1915. Modern Gantt charts also show the dependency relationships between activities and current schedule status.

The precedence diagram method (PDM) is a tool for scheduling activities in a project plan. It is a method of constructing a project schedule network diagram that uses boxes, referred to as nodes, to represent activities and connects them with arrows that show the dependencies. It is also called the activity-on-node (AON) method.

• Critical tasks, noncritical tasks, and slack time
• Shows the relationship of the tasks to each other
• Allows for what-if, worst-case, best-case and most likely scenario

Gantt chart is visual representation of Project Schedules. We can use this for effectively Manage Project Resource, Time and Activities. And a Network Diagram is a linking display of the relationships among all project activities. And a Network diagram is used to represent the various tasks of the project in sequential order by using linkages

2) A Critical Activity is a work elements which must be properly managed to ensure the success of a project, and an organization, program, or an activity that is the critical path.

Critical path activities are the project tasks that must start and finish on time to ensure that the project ends on schedule. A delay in any critical path activity will delay completion of the project, unless the project plan can be adjusted so that successor tasks finish more quickly than planned.

3)

1. Give customers clear and conservative information that will help them estimate their wait time:This reduces their level of anxiety caused by the uncertainty of the situation.
2. Under promise, over deliver: The restaurant host can give customers a longer than expected waiting time, say 20 minutes. If customers end up waiting just 10 minutes, they will feel happier since they expected to wait twice as long.
3. Fill “empty time”: By giving customers something to do while they wait, it can seem like time goes by faster. This is what magazines in waiting rooms are for, but the best option today is to provide free Wi-Fi access to patrons.
4. Do not give the impression of making the same mistake twice: Apologizing to a customer a second time about additional delays will only make them more upset than if you admit to service delays just once.

1: Know your service level target

2: Performance metrics and Queue Management

3: Make changes and compare progress over time

4 Optimize staffing levels:

4)

Little’s law is an equation showing that the average number of customers in a queueing system is equal to their average arrival rate multiplied by the average amount of time they spend in the system. In other words:

“No. items in the queue” = “arrival rate” x “average time spent in the queue“

As I’ve already mentioned, the Little’s law formula is incredibly simple:

L = A x W

In this formula, “L” stands for the number of items inside the queueing system you’re examining. This is also known as “WIP”, as in, the items that are a “work in progress”, and can be pretty much any whole number.

“A” represents the arrival rate and departure rate of items in and out of the business system. This is also sometimes known as “throughput” or “the amount of an item passing into and/or out of a system”, and is sometimes represented as lambda, or “λ”.

The arrival rate is a little confusing at first, but the key to remember is that it will usually be a fraction. This is because you’re measuring the rate at which items enter/depart from the system, rather than the number of items or the time between new arrivals. As such, “A” is always expressed as a fraction showing “one item ever X units of time”, or:

A = (1 item) / (unit of time)

For example, if a new item enters your queue every twenty minutes, your arrival rate is not 20, but instead 1/20.

Finally, “W” is the average amount of time an item spends in your queueing system. This is also known as “lead time” and can also be any unit of time. The only confusing part of this element is that the unit needs to be the same as the one you used for “A” – if you measured the arrival rate in days, then “W” will also be measured in days, and so on.

So, in full English, the law becomes:

Number of items in the system = (the rate items enter and leave the system) x (the average amount of time items spend in the system)

The formula can also be changed to make any of the three elements the focus. The three possible variations are therefore:

• L = A x W
• A = L / W
• W = L / A

5) A Bill of Materials is at heart a list of all the items required to make a product. BOMs include components, raw materials, and sub-assemblies. They may also include intermediate items identifying in-process elements to facilitate planning and other manufacturing processes. Depending on the industry people refer to BOMs differently. For example, in the process industry, it can be called a recipe or formula. A Part List is usually a term used to refer to a single level list of a specific level of an assembly or sub-assembly.

we would need information about inventory status file and MPS file for production