Operations Management
MANAJEMEN PROYEK MUHAMMAD WADUD, SE., M.Si.
POKOK BAHASAN
PENGERTIAN MANAJEMEN PROYEK PERENCANAAN PROYEK PENJADWALAN PROYEK PENGENDALIAN PROYEK TEKNIK MANAJEMEN PROYEK : PERT DAN CPM
MANAJEMEN PROYEK 1.
2.
3.
PLANNING – PENYIAPAN TUJUAN, PENGGAMBARAN PROYEK, DAN PENGORGANISASIAN TIM. SCHEDULING – BERKAITAN DENGAN ORANG, UANG, PASOKAN UNTUK AKTIVITAS TERTENTU DAN MENGAITKAN AKTIVITAS-AKTIVITAS SATU SAMA LAIN CONTROLLING – MENGAWASI SUMBER DAYA, BIAYA, KUALITAS DAN ANGGARAN.
AKTIVITAS MANAJEMEN PROYEK
Planning Objectives Resources Work break-down schedule Organization
Controlling Monitor, compare, revise, action
Scheduling Project activities Start & end times Network
PERENCANAAN PROYEK
Before project
Start of project
Figure 3.1
During project
PENJADWALAN PROYEK
Before project
Start of project Timeline
Figure 3.2
During project
PENGENDALIAN PROYEK
Before project
Start of project Timeline
Figure 3.3
During project
PENGORGANISASIAN PROYEK President Human Resources
Marketing
Project 1
Project 2
Figure 3.2
Finance
Design
Quality Mgt
Production
Mechanical Engineer
Test Engineer
Technician
Electrical Engineer
Computer Engineer
Technician
Project Manager
Project Manager
PERSYARATAN DALAM PENGORGANISASIAN PROYEK 1. 2. 3. 4. 5.
Work can be defined with a specific goal and deadline (Tugas pekerjaan dapat dijelaskan dengan sebuah tujuan yang spesifik dan tenggat waktu) The job is unique or somewhat unfamiliar to the existing organization (pekerjaan bersifat unik atau tidak umum bagi organisasi saat ini) The work contains complex interrelated tasks requiring specialized skills (pekerjaan berisi tugas-tugas rumit yang saling terkait yang memerlukan kemampuan khusus) The project is temporary but critical to the organization (proyek bersifat sementara namun penting bagi organisasi) The project cuts across organizational lines (proyek mempersingkat lini diantara oganisasi)
Matrix Organization Marketing Project 1
Project 2
Project 3
Project 4
Operations
Engineering
Finance
The Role of the Project Manager Highly visible Responsible for making sure that: All necessary activities are finished in order and on time (semua aktivitas2 yang diperlukan selesai dalam urutan yang benar dan tepat waktu)
The project comes in within budget (proyek sesuai dengan anggaran) The project meets quality goals (proyek memenuhi tujuan tekait kualitas) The people assigned to the project receive motivation, direction, and information (orang yang ditugaskan pada proyek menerima motivasi, arahan dan informasi yang diperlukan untuk melakukan pekerjaannya
ETHICAL ISSUES/MASALAH ETIS DALAM MANAJEMEN PROYEK Penawaran hadiah dari kontraktor Tekanan untuk merubah laporan status untuk menutupi kenyataan penundaan Laporan palsu untuk pembebanan waktu dan pengeluaran Tekanan untuk mengkompromikan kualitas agar memperoleh bonus atau menghindari penalti terkait dengan jadwal
Work Breakdown Structure Level (tingkatan struktur perincian kerja) 1. 2. 3. 4.
Project (proyek) Major tasks in the project (tugas utama dalam proyek) Subtasks in the major tasks (subtugas dalam proyek) Activities (or work packages) to be completed (panyel. kerja )
Purposes of Project Scheduling Menunjukkan hubungan dari masing-masing aktivitas dengan yang lainnya dan dengan keseluruhan proyek Mengidentifikasi hubungan yang lebih diutamakan diantara berbagai aktivitas Mendorong pengaturan waktu realistik dan estimasi biaya untuk masing-masing aktivitas Membantu menjadikan lebih baik penggunaan orang, uang dan sumber daya material dengan mengidentifikasi kemacetan utama dalam proyek
Scheduling Techniques-GRAFIK GANTT 1. 2. 3. 4.
Aktivitas Direncanakan Urutan Kinerja Didokumentasikan Waktu Aktivitas Diestimasi Dan Dicatat Waktu Proyek Keseluruhan Dikembangkan
Project Management Techniques (TEKNIK MANAJEMEN PROYEK)
Gantt chart Critical Path Method (CPM) Program Evaluation and Review Technique (PERT)
A Simple Gantt Chart
J Design Prototype
Test Revise Production
F
M
Time A M J
J
A
S
Project Control Reports (KENDALI PROYEK) PERINCIAN BIAYA YANG DETAIL UNTUK MASING-MASING TUGAS KURVA TOTAL PROGRAM BURUH/TK TABEL DISTRIBUSI BIAYA RANGKUMAN BIAYA DAN JAM FUNGSIONAL PERAMALAN BAHAN MENTAH DAN PENGELUARAN LAPORAN VARIAN LAPORAN ANALISIS WAKTU LAPORAN STATUS KERJA
PERT and CPM PERT : SEBUAH TEKNIK MANAJEMEN PROYEK YANG MENGGUNAKAN TIGA WAKTU ESTIMASI UNTUK MASINGMASING AKTIVITAS CPM : TEKNIK MANAJEMEN PROYEK YANG HANYA MENGGUNAKAN SATU FAKTOR WAKTU PERAKTIVITAS
Six Steps PERT & CPM 1. Menentukan proyek dan menyiapkan struktur perincian kerja 2. Mengembangkan hubungan antaraktivitas, menentukan aktivitas mana yang didahulukan dan mana yang harus mengikuti aktivitas lainnya. 3. Menggambarkan jaringan yang menghubungkan semua aktifvitas
Six Steps PERT & CPM 4. Menentukan waktu dan atau estimasi biaya pada masing-masing aktivitas 5. Menghitung jalur waktu terpanjang melaluI jaringan (jalur kritis) 6. Menggunakan jaringan untuk membantu merencanakan, menentukan jadwal mengawasi dan mengendalikan proyek.
Questions PERT & CPM Can Answer 1. When will the entire project be completed?
2. What are the critical activities or tasks in the project? 3. Which are the noncritical activities?
4. What is the probability the project will be completed by a specific date?
Questions PERT & CPM Can Answer 5. Is the project on schedule, behind schedule, or ahead of schedule? 6. Is the money spent equal to, less than, or greater than the budget?
7. Are there enough resources available to finish the project on time? 8. If the project must be finished in a shorter time, what is the way to accomplish this at least cost?
A Comparison of AON and AOA Network Conventions (perbandingan AON dan AOA dalam diagram jaringan) Activity on Node (AON) (a) A
C
B A
(b)
C B B
(c)
A
Figure 3.5
C
Activity Meaning A comes before B, which comes before C A and B must both be completed before C can start
B and C cannot begin until A is completed
Activity on Arrow (AOA)
A
B
C
A B
C
B A
C
A Comparison of AON and AOA Network Conventions Activity on Node (AON) A
C
B
D
(d)
A
C
(e) B Figure 3.5
D
Activity Meaning C and D cannot begin until both A and B are completed
C cannot begin until both A and B are completed; D cannot begin until B is completed. A dummy activity is introduced in AOA
Activity on Arrow (AOA) A
C
B
D
A
C Dummy activity
B
D
A Comparison of AON and AOA Network Conventions Activity on Node (AON)
A
B
(f) C
Figure 3.5
D
Activity Meaning B and C cannot begin until A is completed. D cannot begin until both B and C are completed. A dummy activity is again introduced in AOA.
Activity on Arrow (AOA)
A Dummy activity
B
D C
AOA Network for Milwaukee Paper 2
C 4 (Construct Stack)
Dummy Activity
1
3
D 5 (Pour Concrete/ Install Frame)
6
H (Inspect/ Test)
7
Figure 3.9
Determining the Project Schedule (MENENTUKAN JADWAL PROYEK) Perform a Critical Path Analysis Earliest start (ES) = Waktu paling awal dimana sebuah aktivitas bisa Activity Description Time (weeks) dimulai, asumsikan semua aktivitas pendahulunya telah selesai
A Build internal components 2 Earliest finish (EF) = waktu paling awal dimana sebuah aktivitas bisa B Modifydiselesaikan roof and floor 3 C startConstruct stack 2 Latest (LS) = waktucollection paling lambat dimana sebuah aktivitas bisa dimulai sehingga tidak menunda waktu D Pour concrete and install frame 4 penyelesaian dari keseluruhan proyek E finishBuild burner 4 Latest (LF) = high-temperature waktu paling lambat dimana sebuah aktivitas selesaicontrol sehingga tidak menunda waktu F Install harus pollution system 3 penyelesaian dari keseluruhan proyek G Install air pollution device 5 H Inspect and test 2 Table Total Time (weeks) 25 3.2
Determining the Project Schedule Perform a Critical Path Analysis Activity Name or Symbol
A
Earliest Start
ES
EF
Latest Start
LS
LF
Figure 3.10
2
Earliest Finish
Latest Finish
Activity Duration
Forward Pass Begin at starting event and work forward Earliest Start Time Rule: If an activity has only a single immediate predecessor, its ES equals the EF of the predecessor
If an activity has multiple immediate predecessors, its ES is the maximum of all the EF values of its predecessors ES = Max {EF of all immediate predecessors}
Forward Pass Begin at starting event and work forward Earliest Finish Time Rule: The earliest finish time (EF) of an activity is the sum of its earliest start time (ES) and its activity time
EF = ES + Activity time
ES/EF Network for Milwaukee Paper ES
EF = ES + Activity time Start
0
0
0
ES/EF Network for Milwaukee Paper EF of A = ES of A + 2
ES of A 0
Start
0
A 0
2
0
2
ES/EF Network for Milwaukee Paper 0
A
2 0
Start
0
0
2
EF of B = ES of B + 3
ES of B
B
0
3
3
ES/EF Network for Milwaukee Paper 0
A
2
2 0
Start
2
0
0 0
B
3
2
C
3
4
ES/EF Network for Milwaukee Paper 0
A
2
2 0
Start
2
C
4
2
0
= Max (2, 3) 0
D 3
0
B
3
7
3
4
ES/EF Network for Milwaukee Paper 0
A
2
2
2 0
Start
C
4
2
0
0 0
B
3
3
3
D
4
7
ES/EF Network for Milwaukee Paper 0
A
2
2
2 0
Start
C
4
4
2
F
7
3
0
4
0
E
8
13
4 0
B
3
3
3
D
4
7
H
15
2 G 8
13 5 Figure 3.11
Backward Pass Begin with the last event and work backwards Latest Finish Time Rule: If an activity is an immediate predecessor for just a single activity, its LF equals the LS of the activity that immediately follows it
If an activity is an immediate predecessor to more than one activity, its LF is the minimum of all LS values of all activities that immediately follow it LF = Min {LS of all immediate following activities}
Backward Pass Begin with the last event and work backwards Latest Start Time Rule: The latest start time (LS) of an activity is the difference of its latest finish time (LF) and its activity time
LS = LF – Activity time
LS/LF Times for Milwaukee Paper 0
A
2
2
2 0
Start
C
4
4
2
F
7
3
0
4
0
E
8
13 13
4 0
B
3
3
H
2
15 15
LS = LF D – Activity time G 3
7
4
8
13 5
LF = EF of Project
LS/LF Times for Milwaukee Paper 0
A
2
2
2 0
Start
C
4
4
10
2
F
3
7 13
E
0
8 of LF =4 Min(LS following activity)
0
13 13
4 0
B
3
3
3
D
4
7
G 8
13 5
H
2
15 15
LS/LF Times for LF = Min(4, 10) Milwaukee Paper 0
A
2
2
2 0
Start
2
C
2
4
4
4
10
0
4
4
0 0
B
3
3
3
D
4
7
E
4
F
3
7 13
8
13
8
13 G 8
13
8
13
5
H
2
15 15
LS/LF Times for Milwaukee Paper 0
0
0
0
Start
0
A
2
2
2
2
2
C
2
4
4
4
10
0
4
0
4
0
1
B
3
3
3
4
4
D
4
E
4
F
3
7 13
8
13
8
13 G
7
8
13
8
8
13
5
H
2
15 15
Computing Slack Time After computing the ES, EF, LS, and LF times for all activities, compute the slack or free time for each activity Slack is the length of time an activity can be delayed without delaying the entire project Slack = LS – ES
or
Slack = LF – EF
Computing Slack Time Earliest Earliest Start Finish Activity ES EF
A B C D E F G H
0 0 2 3 4 4 8 13
2 3 4 7 8 7 13 15
Latest Start LS
Latest Finish LF
Slack LS – ES
On Critical Path
0 1 2 4 4 10 8 13
2 4 4 8 8 13 13 15
0 1 0 1 0 6 0 0
Yes No Yes No Yes No Yes Yes Table 3.3
Critical Path for Milwaukee Paper 0
0
0
0
Start
0
A
2
2
2
2
2
C
2
4
4
4
10
0
4
0
4
0
1
B
3
3
3
4
4
D
4
E
4
F
3
7 13
8
13
8
13 G
7
8
13
8
8
13
5
H
2
15 15
ES – EF Gantt Chart for Milwaukee Paper 1
A Build internal components B Modify roof and floor
C Construct collection stack D Pour concrete and install frame E Build hightemperature burner F Install pollution control system G Install air pollution device H Inspect and test
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
LS – LF Gantt Chart for Milwaukee Paper 1
A Build internal components B Modify roof and floor
C Construct collection stack D Pour concrete and install frame E Build hightemperature burner F Install pollution control system G Install air pollution device H Inspect and test
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
Variability in Activity Times CPM assumes we know a fixed time estimate for each activity and there is no variability in activity times PERT uses a probability distribution for activity times to allow for variability
Variability in Activity Times Three time estimates are required Optimistic time (a) – if everything goes according to plan Pessimistic time (b) – assuming very unfavorable conditions Most likely time (m) – most realistic estimate
Variability in Activity Times Estimate follows beta distribution Expected time: t = (a + 4m + b)/6 Variance of times: v = [(b – a)/6]2
Variability in Activity Times
Probability
Estimate follows beta distribution Expected time: Figure 3.12 t = (a + 4m + b)/6 Probability oftimes: Variance of 1 in 100 of Probability < a occurring v = [(b − a)/6]2 of 1 in 100 of > b occurring Activity Time Optimistic Time (a)
Most Likely Time (m)
Pessimistic Time (b)
Computing Variance Optimistic
Most Likely
Pessimistic
Expected Time
Variance
Activity
a
m
b
t = (a + 4m + b)/6
[(b – a)/6]2
A B C D E F G H
1 2 1 2 1 1 3 1
2 3 2 4 4 2 4 2
3 4 3 6 7 9 11 3
2 3 2 4 4 3 5 2
.11 .11 .11 .44 1.00 1.78 1.78 .11 Table 3.4
Probability of Project Completion Project variance is computed by summing the variances of critical activities sp2 = Project variance = (variances of activities on critical path)
Probability of Project Completion Project variance is computed by summing the variances of critical Project variance activities
sp2 = .11 + .11 + 1.00 + 1.78 + .11 = 3.11 Project standard deviation sp =
=
Project variance
3.11 = 1.76 weeks
Probability of Project Completion PERT makes two more assumptions: Total project completion times follow a normal probability distribution Activity times are statistically independent
Probability of Project Completion Standard deviation = 1.76 weeks
15 Weeks Figure 3.13
(Expected Completion Time)
Probability of Project Completion What is the probability this project can be completed on or before the 16 week deadline? Z = due – expected date /sp date
of completion
= (16 wks – 15 wks)/1.76
= 0.57
Where Z is the number of standard deviations the due date or target date lies from the mean or expected date
Probability of Project Completion From Appendix I
What is the probability can .00 .01 this project .07 .08 be completed on or before the 16 week .1 .50000 .50399 .52790 .53188 deadline? .2 .53983 .54380 .56749 .57142 .5 .6
date /s Z.69146 = due .69497 − expected.71566 .71904 p date
.72575
of completion
.72907
.74857
.75175
= (16 wks − 15 wks)/1.76
= 0.57
Where Z is the number of standard deviations the due date or target date lies from the mean or expected date
Probability of Project Completion Probability (T ≤ 16 weeks) is 71.57%
0.57 Standard deviations
15 Weeks Figure 3.14
16 Weeks
Time
Determining Project Completion Time Probability of 0.99 Probability of 0.01
2.33 Standard deviations
From Appendix I Figure 3.15
0
2.33
Z
Variability of Completion Time for Noncritical Paths Variability of times for activities on noncritical paths must be considered when finding the probability of finishing in a specified time Variation in noncritical activity may cause change in critical path
What Project Management Has Provided So Far The project’s expected completion time is 15 weeks There is a 71.57% chance the equipment will be in place by the 16 week deadline Five activities (A, C, E, G, and H) are on the critical path Three activities (B, D, F) are not on the critical path and have slack time A detailed schedule is available
Trade-Offs And Project Crashing It is not uncommon to face the following situations: The project is behind schedule The completion time has been moved forward
Shortening the duration of the project is called project crashing
Factors to Consider When Crashing A Project The amount by which an activity is crashed is, in fact, permissible Taken together, the shortened activity durations will enable us to finish the project by the due date The total cost of crashing is as small as possible
Steps in Project Crashing 1. Compute the crash cost per time period. If crash costs are linear over time: (Crash cost – Normal cost) Crash cost per period = (Normal time – Crash time) 2. Using current activity times, find the critical path and identify the critical activities
Steps in Project Crashing 3. If there is only one critical path, then select the activity on this critical path that (a) can still be crashed, and (b) has the smallest crash cost per period. If there is more than one critical path, then select one activity from each critical path such that (a) each selected activity can still be crashed, and (b) the total crash cost of all selected activities is the smallest. Note that the same activity may be common to more than one critical path.
Steps in Project Crashing 4. Update all activity times. If the desired due date has been reached, stop. If not, return to Step 2.
Crashing The Project Time (Wks) Activity Normal Crash
A B C D E F G H
2 3 2 4 4 3 5 2
1 1 1 2 2 2 2 1
Cost ($) Crash Cost Critical Normal Crash Per Wk ($) Path?
22,000 30,000 26,000 48,000 56,000 30,000 80,000 16,000
22,750 34,000 27,000 49,000 58,000 30,500 84,500 19,000
750 2,000 1,000 1,000 1,000 500 1,500 3,000
Yes No Yes No Yes No Yes Yes Table 3.5
Crash and Normal Times and Costs for Activity B Activity Cost
Crash
$34,000 —
Crash Cost/Wk =
Crash $33,000 — Cost
=
$34,000 – $30,000 3–1 $4,000 = = $2,000/Wk 2 Wks
$32,000 — $31,000 —
$30,000 —
Normal Cost Figure 3.16
Crash Cost – Normal Cost Normal Time – Crash Time
Normal
—
| 1 Crash Time
| 2
| 3 Normal Time
Time (Weeks)
Critical Path And Slack Times For Milwaukee Paper 0
0
0
0
Start
0
0
A
2
2
2
2
2
Slack = 0
C
2
4
4
4
10
Slack = 0 4
0
4
0
1
B
3
3
3
4
4
Slack = 1
D
4
E
4
F
3
7 13
Slack = 6 8
13
8
13
Slack = 0 7
8
13
8
8
13
Slack = 1
2
15 15
Slack = 0
G
5
H
Slack = 0
Figure 3.17
Advantages of PERT/CPM 1. Especially useful when scheduling and controlling large projects 2. Straightforward concept and not mathematically complex 3. Graphical networks help highlight relationships among project activities 4. Critical path and slack time analyses help pinpoint activities that need to be closely watched
Advantages of PERT/CPM 5. Project documentation and graphics point out who is responsible for various activities 6. Applicable to a wide variety of projects 7. Useful in monitoring not only schedules but costs as well
Limitations of PERT/CPM 1. Project activities have to be clearly defined, independent, and stable in their relationships 2. Precedence relationships must be specified and networked together 3. Time estimates tend to be subjective and are subject to fudging by managers 4. There is an inherent danger of too much emphasis being placed on the longest, or critical, path
Project Management Software There are several popular packages for managing projects
Primavera MacProject Pertmaster VisiSchedule Time Line Microsoft Project
Using Microsoft Project
Program 3.1
Using Microsoft Project
Program 3.2
Using Microsoft Project
Program 3.3
Using Microsoft Project
Program 3.4
Using Microsoft Project
Program 3.5
Using Microsoft Project
Program 3.6
Using Microsoft Project
Program 3.7
