-
Copyright 2006 John Wiley & Sons, Inc.Beni AsllaniUniversity
of Tennessee at ChattanoogaOperations Management - 5th
EditionChapter 8 SupplementRoberta Russell & Bernard W. Taylor,
IIIWork Measurement
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Lecture
OutlineTime StudiesWork Sampling
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Work
MeasurementDetermining how long it takes to do a jobGrowing
importance in service sector
Services tend to be labor-intensiveService jobs are often
repetitiveTime studies
Standard timeis time required by an average worker to perform a
job onceincentive piece-rate wage system based on time study
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Stopwatch Time Study Basic StepsEstablish standard job
methodBreak down job into elementsStudy jobRate workers performance
(RF)Compute average time (t)
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Stopwatch Time Study Basic Steps (cont.)Compute normal time
Compute standard time
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Performing a Time Study
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Performing a Time Study (cont.)
Normal time = (Elemental average)(rating factor)Nt = ( t )(RF) =
(0.053)(1.05) = 0.056Normal Cycle Time = NT = Nt = 0.387ST = (NT)
(1 + AF) = (0.387)(1+0.15) = 0.445 min
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Performing a Time Study (cont.)Example 17.3
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*
Number of CyclesTo determine sample size:
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*
Number of Cycles: ExampleAverage cycle time = 0.361Computed
standard deviation = 0.03Company wants to be 95% confident that
computed time is within 5% of true average time
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Elemental Times FilesElemental standard time files
predetermined job element timesPredetermined motion times (for
micro-motions)Time measurement units
TMUs = 0.0006 minute100,000 TMU = 1 hourAdvantages
worker cooperation unnecessaryworkplace uninterruptedperformance
ratings unnecessaryconsistent.Disadvantages
ignores job contextmay not reflect skills and abilities of local
workers
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*MTM
Table for MOVE
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Work
SamplingDetermines the proportion of time a worker spends on
activitiesPrimary uses of work sampling are to determine
ratio delaypercentage of time a worker or machine is delayed or
idleanalyze jobs that have non-repetitive tasksCheaper and easier
approach to work measurement
Copyright 2006 John Wiley & Sons, Inc.
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Steps of
Work SamplingDefine job activitiesDetermine number of observations
in work sample
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Steps of
Work Sampling (cont.)Determine length of sampling periodConduct
work sampling study, record observationsPeriodically re-compute
number of observations
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement 8-*Work
Sampling: Example
Copyright 2006 John Wiley & Sons, Inc.*
-
Copyright 2006 John Wiley & Sons, Inc.Supplement
8-*Copyright 2006 John Wiley & Sons, Inc.All rights reserved.
Reproduction or translation of this work beyond that permitted in
section 117 of the 1976 United States Copyright Act without express
permission of the copyright owner is unlawful. Request for further
information should be addressed to the Permission Department, John
Wiley & Sons, Inc. The purchaser may make back-up copies for
his/her own use only and not for distribution or resale. The
Publisher assumes no responsibility for errors, omissions, or
damages caused by the use of these programs or from the use of the
information herein.
Copyright 2006 John Wiley & Sons, Inc.
*
*
*
*
*
*
*
*
*
*