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Flashcards in Little's Law & Lean Deck (34)
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1
Q

What is little’s law?

A

Throughput (Th)= Work In Process (WIP) x Cycle Time (CT)

2
Q

What is throughout efficiency?

A

Throughput efficiency (%) = Work content x 100 Throughput time

refers to the work content needed to produce an item in a process expressed in terms of a percentage of total throughput time.

3
Q

The lean philosophy of operations

A

Eliminate waste

Involve everyone

Continuous improvement

4
Q

Lean as a set of techniques for managing operations

A
Basic working practices Design for manufacture Operations focus 
Small, simple machines 
Flow layout
TPM
Set-up reduction
Total people involvement Visibility
JIT supply
5
Q

Lean as a method of planning and control

A

Pull scheduling
Kanban control
Levelled scheduling
Mixed modelling Synchronization

6
Q

How does lean eliminate waste?

A
  • Identify the causes and types of waste by understanding the customer perspective
  • Eliminate waste through streamlined flow using e.g. Value stream mapping
  • Eliminate waste through matching supply and demand e.g. Pull system
  • Eliminate waste through minimizing variability e.g. Level delivery Schedule
  • Eliminate waste through flexible processes
  • Can be viewed through 5S
7
Q

What are the basic lean principles

A
  1. 1 Piece Flow
    - move away from batting, backlog and queues
  2. Standard Work
    - reduce variation & complexity
  3. 5S
    - sort; straighten; scrub; standardise; sustain
  4. Pull systems
    - create signals to pull products/ services. obvious when something is empty
8
Q

What is visual management

A

ability to see the process

9
Q

what is value stream mapping

A

understand how value is created and delivered

focuses on value-adding activities and distinguishes between value-adding and non-value-adding activities.

  • Eliminate waste through reducing variability
    Eliminate waste through streamlined flow
10
Q

Criticisms of lean process improvement

A
  • One size fits all solutions
  • Too much standardization and people management = in inhumane working conditions
  • Top down rather than bottom up problem solving
  • Application of lean tools/techniques without understanding the philosophy and culture
11
Q

define lean synchronisation

A

moving towards the elimination of all waste in order to develop an operation that is

  • faster,
  • more dependable,
  • produces higher quality products and services
  • operates at low cost’.
12
Q

lean synchronisation is synonymous with…

A

continuous flow

manufacture high value-added manufacture

stockless production low-inventory production

fast-throughput manufacturing

lean manufacturing

Toyota production system

short cycle time manufacturing

13
Q

What are the four elements of lean?

A

Waste elimination
Behaviour
Synchronisation
Customer focus

14
Q

what is the ‘river and rocks’ analogy

A
  • reducing the level of inventory (water) allows operations management (ship) to see problems in the process (rocks)
15
Q

What is the traditional approach?

A
  • focus on high capacity utilisation
  • more production at each stage
  • extra production goes into inventory because of continuing stoppages at stages
  • high inventory means less chance of problems being exposed and solved
  • more stoppages because of problems
16
Q

What is the lean approach?

A
  • focus on producing only when needed
  • lower capacity utilisation, but
  • no surplus production goes into inventory
  • low inventory so problems are exposed and solved
  • fewer stoppages
17
Q

Causes of waste

A

Mura
- ‘lack of consistency’/ unevenness = periodic overloading of staff or equipment
Muri
- unreasonable= unnecessary/ unreasonable requirements put on a process will result in poor outcomes
Muda
- activities that are wasteful = do not add value to the operation or the customer.

18
Q

what are waste activities?

A

consume time, resources and space, but do not contribute to satisfying customer needs

19
Q

Seven types of waste

A
 Over-production. 
 Waiting time
 Transport 
 Process.
 Inventory 
 Motion
 Defects
20
Q

What is over-production waste?

A

Make more than is required by the customer, or to make it earlier than required.

21
Q

What is waiting time waste?

A

Any delay between when one process step/activity ends and the next step/activity begins

22
Q

What is transport waste?

A

Movement of work between departments or offices that does not add to the value of the product or service

23
Q

What is (over) processing waste?

A

Adding more value to a service or product than customers want or will pay for.

24
Q

what is inventory waste?

A

More materials or information on hand than is currently required

25
Q

What is motion waste?

A

Needless movement of people

While “transportation” refers to the movement of the work, “motion“ involves movement of workers

26
Q

What is defects/ inspection waste

A

Any aspect of the product/service that does not conform to customer needs

27
Q

example of waste in a hospital

A

Over-production

  • requesting unnecessary tests from pathology
  • keeping investigation slots ‘just in case’

Waiting
- Patients, theatre, staff results, prescriptions
and medicines
- doctors to discharge patients

Transport
– documents carried out to be signed by
various wards and managers

Over-processing

  • duplication of information
  • asking for patients’ details several times

Inventory
– excess stock in storerooms
- patients waiting to be discharged
- waiting lists

Rework

  • readmission because of failed discharge
  • repeating tests because correct information was not provided

Motion
- unnecessary staff movement looking
for paperwork
- not having basic equipment in every examination room

28
Q

What are the 5’s?

A

Sort
-organise separate the needed from the rarely used

Straighten
- arrange and identify for ease of use

Shine
- clean and looks for ways to keep it clean

Standardize
- create rules to sustain the first 3 S’s

Sustain
- management audit to ensure adherence

n.b. continuous improvement

29
Q

How to Sort (Seri)?

A

 Eliminate all unnecessary items!!
 Unnecessary refers to those things that are not needed for current work

 Keep only things that are required in doing the job

30
Q

How to Straighten (Seiton)?

A

Arrange items so that they can be found quickly by Anybody, Anywhere, Anytime.
Items should be easy to find, easy to use and easy to put away.
 Tools
e.g. Colour Coding , Signboards, Labeling

 Keep things in Order

31
Q

How to Shine (Sieso) ?

A

 Everything is clean, neat, tidy and ready to use
 Tools:
e.g. Five Minute Shine
Cleaning & Inspection Checklists
Checklist of Activities Needing Maintenance

 A clean work place enhances health and productivity

32
Q

how to Standardize (Seiketsu)?

A

 To prevent setbacks in the first 3 pillars (Sort, Set In Order and Shine)
 Tools
eg. Best Practice documentation and sharing Checklists & job cycle charts

 Learn a smarter way to Work

33
Q

how to Sustain (Shitsuke)?

A

 To make 5S a habit in the way we do our day-to-day activities
 Tools include…..
e.g. 5 S contests
Visual management boards showing 5S audit
Slogans
Handbooks
Poka Yoke!

 Make 5 S a habit

34
Q

Criticisms of Lean Process Improvement

A
  • One size fits all solutions
  • Top down rather than bottom up problem solving
  • Application of lean tools/ techniques without understanding the philosophy and culture
  • Too much standardization and people management might result in inhumane working conditions
  • Thus might be a paradox rather than panacea if not managed well