Transcript
FORCE FIELD ANALYSIS
Failures Mode and Effects Analysis •
Requires a thorough knowledge of –
–
•
functions of the components contribution of those components to function of o f the system
For every failure failure mode at a low level, failure consequences are analysed at –
the local level
–
the system level
Failures Mode and Effects Analysis •
Requires a thorough knowledge of –
–
•
functions of the components contribution of those components to function of o f the system
For every failure failure mode at a low level, failure consequences are analysed at –
the local level
–
the system level
Failures Mode and Effects Analysis •
design-FMEA for design reviews –
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definition and limiting of the system choice of complexity level check of component functions check of system functions identification of possible failure modes identification of consequences of failures
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possibility of failure detection and failure localisation assessment of seriousness of failure
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identification of failure causes
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interdependence interdependence of failures documentation
Failures Mode and Effects Analysis •
quantitative design-FMEA a.k.a. FMECA Failure Mode, Effects and Criticality Analysis –
consider every component
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quantify and rank different failure modes •
F = probability of failure
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A = seriousness (consequences of failure)
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U = probability of detection
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subjective judgements on a scale of 1-5 or 1-10
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Product (F*A*U) = Risk Priority Number (RPN)
Failures Mode and Effects Analysis •
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Process-FMEA for –
pre-production engineering
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design of process control
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process improvement
FMEA is efficient where component failure leads directly to system failure for more complex failures, FMEA may be supplemented by Fault Tree Analysis (FTA)
Fault Tree Analysis •
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Logical chart of occurrences to illustrate cause and effects developed by DF Haasl, HA Watson, BJ Fussell and WE Vesely initially at Bell Telephone Laboratories then North American Space Industry
Fault Tree Analysis •
Common symbols used 1 –
main event
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basic event
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incompletely analysed event
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restriction
Fault Tree Analysis •
Common symbols used 2 +
1
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or-gate
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and-gate
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transfer to or from another place
&
Kurt Lewin [1890 - 1947]
Lewin’s Three-Step
Model of Lewin Organizational Change
Force field analysis is a management technique developed by Kurt Lewin, a pioneer in the field of social sciences, for diagnosing situations. Lewin assumes that in any situation there are both driving and restraining forces that influence any change that may occur:
Driving Forces Restraining Forces Equilibrium
Force Field Analysis is a useful technique for looking at all the forces for and against a decision. In effect, it is a specialized method of weighing pros and cons. By carrying out the analysis you can plan to strengthen the forces supporting a decision, and reduce the impact of opposition to it.
Purpose
Defining Concept of “Field”…… •
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Analytical Purpose FFA is an analysis technique to identify forces that either drive or restrain planned change aimed at solving a problem in an organization. It is a creative activity that can be used by needs analysts as they focus on solutions which organization make a transformation from the ‘desired
‘current
(problem)
will help an state’
to the
(solved) state’ as they identify interventions to improve performance.
FFA can be used to: •
Identify the forces which support change as well as those which will act against it.
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Assess the causes of performance problems or inhibitors to business opportunities.
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Evaluate the relative strength of forces that affect alternative solutions to performance problems or business opportunities. Help analyze and prioritize solutions to problems or areas needing improvement .
Field Force Process is … •
Unfreezing--melting away resistance
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Change--departure from the status quo
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Refreezing--change becomes routine
WHY TO USE? Force-field analysis focuses our attention on ways of reducing the hindering forces and encouraging the positive ones.
State the problem or desired state and make sure that all team members understand. Brainstorm the positive and negative forces. Review and clarify each force or factor. What is behind each factor? What works to balance the situation?
Force-field Model of Change Desired state
Restraining forces
Status quo
Driving forces
Time
How to Carry it
Carrying Out a Force Field Analysis: To carry out a force field analysis, follow the following steps: •
List all forces for change in one
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Assign a score to each force, from 1
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Draw a diagram showing the forces
column, and all forces against change in another column. (weak) to 5 (strong).
for and against, and the size of the forces.
DIAGRAM
A model built on this idea that forces - persons, habits, customs, attitudes - both drive and restrain change. It can be used at any level (personal, project, organizational, network) to visualize the forces that may work in favor and against change initiatives. The diagram helps its user picture the " tug-of-war " between forces around a given issue.
Example for F.F.A
:
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Investigate the Balance of Power involved in issue Identify the most
important player (Stake holder)
& target group for the campaign on the issue Identify opponents and Allies Identify how to influence each target group
HOW TO CONDUCT: Following
are taken:
Describe the current situation . Describe the desired situation .
Identify where the current situation will go if no action is taken .
List all the forces driving change toward the desired situation . List all the forces resisting change toward the desired situation . Discuss and interrogate all of the forces: are they valid?
There is no special training for this tool - just good listening skills and the ability to capture comments and help the group to distill them into an action plan that minimizes/ removes the negative forces and maximizes the positive forces. Force Field Analysis is best run by someone who has been involved in the topic under discussion or is familiar with the subject area.
A flip chart and pens are required. You can also use 'post-it' notes instead of arrows and use a brainstorming technique such as a nominal group to derive a comprehensive list of forces before as a group posting them to a main board for discussion.
Advantages & Limitations of F.F.A.
Advantages of Force Field Analysis •
Brings into the open factors which will work for and against the closing of a gap
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Identified by a needs analysis.
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Helps to recognize circumstances which can and cannot be changed.
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Provides a means to analyze ways to minimize or eliminate barriers to goal attainment.
The Limitations of Force Field Analysis •
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Process is subjective and requires collaborative thinking and agreement Concerning forces for and against the solution to a particular problem. May oversimplify the relationships between factors that impact a problem. All aspects of a problem may not be identified.
The Principal Characteristics of Lewin's field theory is summarized as follows: 1.Behavior is a function of the field that exists at the time the behavior occurs. 2. Analysis begins with the situation as a whole from which are differentiated the component parts. 3. The concrete person in a concrete situation can represented mathematically.