Your SlideShare is downloading. ×
Om3
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Om3

728

Published on

Published in: Business, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
728
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
29
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. H K DANGI
    1
    OPERATIONS MANAGEMENT Lecture 3
    Hamendra Dangi
    hkdangi@fms.edu
    9968316938
  • 2. H K DANGI
    2
    Job Design
    The act of specifying the contents and methods of jobs.
    Job designers focus on
    • what will be done in a job,
    • 3. who will do the job,
    • 4. how the job will be done, and
    • 5. where the job will be done.
    The objectives of job design include productivity, safety, and quality of work life.
    Ergonomics is the incorporation of human factors in the design of the workplace.
    It relates to design of equipment, design of work methods, and the overall design
    of the work environment.
    Current practice in job design contains elements of two basic schools of thought.
    One might be called the efficiency school because it emphasizes a systematic,
    logical approach to job design; the other is called the behavioral school
    l because it emphasizes satisfaction of wants and needs.
    2
  • 6. H K DANGI
    3
    Specialization
    http://www.baskent.edu.tr/~kilter
    3
  • 7. H K DANGI
    4
    Behavioral Approaches to Job Design
    Job enlargement. Giving a worker a larger portion of the total task, by horizontal loading. (horizontal loading)
    Job rotation. Workers periodically exchange jobs. means having workers periodically exchange jobs.
    Job enrichment. Increasing responsibility for planning and coordination tasks, by vertical loading. (vertical loading)
    http://www.baskent.edu.tr/~kilter
    4
  • 8. H K DANGI
    5
    Methods Analysis
    Selecting an Operation to Study
    Documenting the Current Method
    Analyzing the Job and Proposing New Methods
    Installing the Improved Method
    The Follow-Up
    Analyzing and improving methods is facilitated by the use of various charts
    such as flow process charts and worker-machine charts.
    http://www.baskent.edu.tr/~kilter
    5
  • 9. H K DANGI
    6
    Flow process chartsare used to review and critically examine the overall sequence of an operation by focusing on the movements of the operator or the flow of materials.
    http://www.baskent.edu.tr/~kilter
    6
  • 10. H K DANGI
    7
    http://www.baskent.edu.tr/~kilter
    7
  • 11. H K DANGI
    8
    http://www.baskent.edu.tr/~kilter
    8
  • 12. H K DANGI
    9
    Motion Study
    systematic study of the human motions used to perform an operation.
    Motion study principles 
    The use of the human body.
    The arrangement and conditions of the workplace.
    The design of tools and equipment.
    http://www.baskent.edu.tr/~kilter
    9
  • 13. H K DANGI
    10
    Working Conditions
    Temperature and Humidity.  
    Ventilation.   
    Illumination.    
    Noise and Vibrations.
    Work Breaks.
    Safety. 
    Ethical Issues.
    http://www.baskent.edu.tr/~kilter
    10
  • 14. H K DANGI
    11
    Work Measurement
    standard timeis the amount of time it should take a qualified worker to complete
    a specified task, working at a sustainable rate, using given methods, tools and
    equipment, raw material inputs, and workplace arrangement.
    • stopwatch time study
    • 15. historical times
    • 16. predetermined data
    • 17. work sampling
    http://www.baskent.edu.tr/~kilter
    11
  • 18. H K DANGI
    12
    where
    n = Sample size needed
    z = Number of normal standard deviations needed for desired confidence
    s = Sample standard deviation
    a = Desired accuracy percentage
    x = Sample mean
    where
    e = Maximum acceptable errror
    12
  • 19. H K DANGI
    13
    Example
    A time study analyst wants to estimate the time required to perform a certain job.
    A preliminary study yielded a mean of 6.4 minutes and a standard deviation of
    2.1 minutes. The desired confidence is 95 percent. How many observations will
    he need (including those already taken) if the desired maximum error is
    a. ±10 percent of the sample mean?
    b. One-half minute?
    http://www.baskent.edu.tr/~kilter
    13
  • 20. H K DANGI
    14
    h = .05 x = 3.00 s = 1.0
    z = 1.96 (from Table S10.1 or Appendix I)
    2
    zs
    hx
    n =
    2
    1.96 x 1.0
    .05 x 3
    n = = 170.74 ≈ 171
    Time Study Example
    Desired accuracy with 5%
    Confidence level = 95%
    Sample standard deviation = 1.0
    Sample mean = 3.00
  • 21. H K DANGI
    15
    Time Studies
    • Involves timing a sample of a worker’s performance and using it to set a standard
    • 22. Requires trained and experienced observers
    • 23. Cannot be set before the work is performed
  • H K DANGI
    16
    Time Studies
    Define the task to be studied
    Divide the task into precise elements
    Decide how many times to measure the task
    Time and record element times and rating of performance
  • 24. H K DANGI
    17
    Sum of the times recorded to perform each element
    Number of observations
    Average observed time
    =
    Average observed time
    Performance rating factor
    Normal time = x
    Time Studies
    Compute average observed time
    Determine performance rating and normal time
  • 25. H K DANGI
    18
    Total normal time
    1 - Allowance factor
    Standard time =
    Time Studies
    Add the normal times for each element to develop the total normal time for the task
    Compute the standard time
  • 26. H K DANGI
    19
    Rest Allowances
    • Personal time allowance
    • 27. 4% - 7% of total time for use of restroom, water fountain, etc.
    • 28. Delay allowance
    • 29. Based upon actual delays that occur
    • 30. Fatigue allowance
    • 31. Based on our knowledge of human energy expenditure
  • H K DANGI
    20
    Rest Allowances
    1. Constant allowance
    (A) Personal allowance ……………... 5
    (B) Basic fatigue allowance ………… 4
    2. Variable allowances:
    (A) Standing allowance ……………… 2
    (B) Abnormal position
    (i) Awkward (bending) ………… 2
    Very awkward (lying, stretching) …………………… 7
    Figure S10.1
  • 32. H K DANGI
    21
    Rest Allowances
    Use of force or muscular energy in lifting, pulling, pushing
    Weight lifted (pounds)
    20 …………………………………… 3
    40……………………………………. 9
    60……………………………………. 17
    Bad light:
    Well below recommended…. 2
    Quite inadequate……………. 5
    Figure S10.1
  • 33. H K DANGI
    22
    Rest Allowances
    (E) Atmospheric conditions (heat and humidity) …………… 0-10
    Close attention:
    (i) Fine or exacting……………….. 2
    (ii) Very fine or very exacting…… 5
    Noise level:
    (i) Intermittent—loud…………….. 2
    (ii) Intermittent—very loud or high-pitched………………... 5
    Figure S10.1
  • 34. H K DANGI
    23
    Rest Allowances
    Mental strain:
    (i) Complex or wide span of attention.…………………….. 4
    (ii) Very complex………………….. 8
    Tediousness:
    (i) Tedious…………..……………… 2
    (ii) Very tedious.…………………… 5
    Figure S10.1
  • 35. H K DANGI
    24
    Normal time = (Average observed time) x (Rating factor)
    = (4.0)(.85)
    = 3.4 minutes
    Normal time
    1 - Allowance factor
    Standard time = = =
    3.4
    1 - .13
    3.4
    .87
    = 3.9 minutes
    Time Study Example
    Average observed time = 4.0 minutes
    Worker rating = 85%
    Allowance factor = 13%
  • 36. H K DANGI
    25
    Cycle Observed (in minutes)
    Performance
    Job Element 1 2 3 4 5 Rating
    Compose and type letter 8 10 9 21* 11 120%
    Type envelope address 2 3 2 1 3 105%
    Stuff, stamp, seal, and 2 1 5* 2 1 110% sort envelopes
    Time Study Example
    Allowance factor = 15%
    Delete unusual or nonrecurring observations (marked with *)
    Compute average times for each element
    Average time for A = (8 + 10 + 9 + 11)/4 = 9.5 minutes
    Average time for B = (2 + 3 + 2 + 1 + 3)/5 = 2.2 minutes
    Average time for C = (2 + 1 + 2 + 1)/4 = 1.5 minutes
  • 37. H K DANGI
    26
    Time Study Example
    Compute the normal time for each element
    Normal time = (Average observed time) x (Rating)
    Normal time for A = (9.5)(1.2) = 11.4 minutes
    Normal time for B = (2.2)(1.05) = 2.31 minutes
    Normal time for C = (1.5)(1.10) = 1.65 minutes
    Add the normal times to find the total normal time
    Total normal time = 11.40 + 2.31 + 1.65 = 15.36 minutes
  • 38. H K DANGI
    27
    Standard time =
    = = 18.07 minutes
    Total normal time
    1 - Allowance factor
    15.36
    1 - .15
    Time Study Example
    Compute the standard time for the job
  • 39. H K DANGI
    28
    http://www.baskent.edu.tr/~kilter
    28

×