MANAGEMENT OF LARGE PROJECTS
PROJECT MANAGEMENT ACTIVITIES
PROJECT ORGANIZATION WORKS BEST WHEN: Work
can be defined with a specific goal and deadline The job is unique or somewhat unfamiliar to the existing organization The work contains complex interrelated tasks requiring specialized skills The project is temporary but critical to the organization
PROJECT PLANNING, SCHEDULING, AND CONTROLLING Project Planning 1. Setting goals 2. Defining the project 3. Tying needs into timed project activities 4. Organizing the team
Time/cost estimates Budgets Engineering diagrams Cash flow charts Material availability details
Project Scheduling 1. Tying resources to specific activities 2. Relating activities to each other 3. Updating and revising on a regular basis
CPM/PERT Gantt charts Milestone charts Cash flow schedules
Project Controlling 1. Monitoring resources, costs, quality, and budgets 2. Revising and changing plans 3. Shifting resources to meet demands Before Project 5
During Project
Reports • budgets • delayed activities • slack activities
Project Planning, Scheduling, and Controlling
PROJECT PLANNING Establishing
objectives Defining project Creating work breakdown structure (WBS)
Determining
resources Forming organization
A work breakdown structure defines the hierarchy of project tasks, subtasks, and work packages
Level Program 1 2
8
Project 1
Project 2
Task 1.1
Task 1.2
3
Subtask 1.1.1
4
Work Package 1.1.1.1
Subtask 1.1.2 Work Package 1.1.1.2
Work Breakdown Structure
Work Breakdown Structure – An Example
Work Breakdown Structure – An Example
Gray&Larson, 2003
Uses of the WBS 1. Develop the master project plan - timeline to the major work packages and milestones - dependencies between work packages 2. Estimate resource requirements (and costs) 3. Develop project organization (assign responsibilities) 4. Facilitate other management - Quality Management - Risk Management 5. Provides mechanism for project control 6. Go-ahead approval or work packages 7. Release of resources/funds 8. Enable project progress to be reported at different level of detail 12
Integration of WBS and OBS
Gray&Larson, 2003
Work Package Estimates
Gray&Larson, 2003
Work packages
Defines work (what) Identifies time to complete (how long) Identifies a time-phased budget to complete (cost) Identifies resources needed to complete (how much) Identifies a single person responsible (who) Identifies monitoring points for measuring progress
WHAT’S IN PROJECT SCHEDULING
Identifying precedence relationships Sequencing activities Determining activity times & costs Estimating material & worker requirements Determining critical activities
© 1984-1994 T/Maker Co.
GANTT CHART
GANTT CHART EXAMPLE
Activity Design Build Test
J
Time Period F M A M
J
J
GANTT CHART EXAMPLE: RESEARCH Stage
Week
Design of data collection instrument Data Collection Design Data Collection Data Processing & Analysis Development of standard mechanism & instrument of Mapping Conclusion
2
3
4
5
6
7
8
9
10
11
12 Information Technology Project Management, Fifth Edition, Copyright 2007
Literature Review
1
22
Network
techniques Developed in 1950’s
CPM by DuPont for chemical plants (1957) PERT by Booz, Allen & Hamilton with the U.S. Navy, for Polaris missile (1958)
Consider
precedence relationships and interdependencies Each uses a different estimate of activity times
QUESTIONS WHICH MAY BE ADDRESSED BY PERT & CPM
The Six Steps Common to PERT & CPM 1. 2. 3. 4. 5. 6.
Define the project and prepare the work breakdown structure, Develop relationships among the activities. (Decide which activities must precede and which must follow others.) Draw the network connecting all of the activities Assign time and/or cost estimates to each activity Compute the longest time path through the network. This is called the critical path Use the network to help plan, schedule, monitor, and control the project
Two approaches used: Activity On Node (AON) Activities are drawn as nodes, each event is represented by arch. Activity On Arch (AOA) Activity is drawn as arch, while events are represented by nodes.
Label Aktivitas
Kegiatan Pendahulu ( Predecessor )
Waktu (jam)
Pesan bahan
A
-
1
Pesan alat
B
-
1
Timbang bahan
C
A
2
Campur bahan
D
A
3
Siapkan alat
E
B
1
Pasang kawat
F
D
3
Sambung kawat
G
D
2
Susun Bata
H
C
5
Potong balok
I
E
3
Pasang penyangga
J
I, G
3
Tuang adukan bahan
K
H, F
8
Bongkar penyangga
L
K, J
2
Deskripsi Aktivitas
Activity
Description
Immediate Predecessors
Duration
A
Build internal components
-
3
B
Modify roof and floor
-
4
C
Construct collection stack
A
6
D
Pour concrete and install frame
A, B
6
E
Build high-temperature burner
C
3
F
Install pollution control system
C
4
G
Install air pollution device
D, E
8
H
Inspect and test
F, G
2
AON
AOA
2
C Construct stack
1
3
E Build burner
Dummy Activity
4
D Pour concrete/ Install frame
5
6
H Inspect/Test
7
A n : Activity number A : Activity name x : Duration of activity A ES : Earliest Start LS : Latest Start
Arch X
ES n
Arch : activity Node : event
Simpul
LS
Activity on Arch (AOA) A
B
Activity on Arch (AOA) EF ES Activity name
Event number
E
4 3
6 5
LS
8
4
Duration
9
LF
ACTIVITY ON NODES (AON)
Latest Start
LS
Activity Duration
ES
Activity Name
Earliest Start
EF
Earliest Finish
LF
Latest Finish
ES EF LS LF Res Dur
: Waktu mulai paling awal (Early Start) : Waktu selesai paling awal (Early Finish) : Waktu mulai paling akhir (Least Start) : Waktu selesai paling akhir (Least Finish) : Sumber daya (Resources) : Durasi Proyek (Duration)
Example
Kode 1.1
Aktivitas
Predecessor
Durasi
Tahap Pertama
1.1.1
A
-
5
1.1.2
B
-
10
1.1.3
C
-
8
1.2
Tahap Kedua
1.2.1
D
A
6
1.2.1
E
A
12
1.3
Tahap Ketiga
1.3.1
F
B,D
7
1.3.1
G
C
4
1.3.2
H
E,F,G
6
1.3.3
I
G
10
PERT
Lintasan
kritis merupakan merupakan suatu lintasan dalam jaringan kerja yang tidak ada satupun aktivitas didalamnya yang memiliki slack. Lintasan
dimana ES=LS dan EF=LF untuk semua aktivitas disepanjang lintasan.
Lintasan
kritis merupakan lintasan dengan durasi terlama di sepanjang jaringan.
Pentingnya
identifikasi lintasan kritis adalah : bahwa apabila aktivitas-aktivitas di sepanjang lintasan kritis terlambat waktu mulainya ataupun molor lama pengerjaannya, hal itu pasti akan memperpanjang umur proyek.
Di
sisi lain, apabila kita ingin mempersingkat umur proyek, dapat dilakukan dengan cara mengurangi total waktu pengerjaan aktivitas-aktivitas di sepanjang lintasan kritis.
Program Evaluation and Review Technique (PERT)
Program Evaluation and Review Technique (PERT)
Program Evaluation and Review Technique (PERT)
Program Evaluation and Review Technique (PERT)
semakin besar nilai v, semakin kecil kemungkinan te bisa dipercaya, dan semakin tinggi kemungkinan kegiatan yang bersangkutan selesai lebih awal atau lebih lambat dari pada te.
PROGRAM EVALUATION AND REVIEW TECHNIQUE (PERT) jika
semua kegiatan dalam proyek sudah diketahui beserta waktu yang diharapkan te, maka umur proyek bisa ditentukan dari jumlah total ke dalam lintasan kritis (LK).
Te = ∑ te LK
dimana
Te adalah waktu yang diharapkan dari kegiatan-kegiatan dalam lintasan kritis.
peluang
selesainya € proyek sebelum waktu Te dan sesudah waktu Te masing-masing adalah lebih kecil dari 50% dan lebih besar dari 50%.
variasi
dari umur proyek adalah jumlah variasi pada tiap kegiatan dilintasan kritis proyek, atau
Vp = ∑ v LK
Program Evaluation and Review Technique (PERT)
Dari gambar disamping bisa dilihat bahwa umur proyek adalah 29 hari.
Sedangkan variansi untuk lintasan kritis 1-2-5-7-8 adalah sebesar 2,78+0,44 +1,78+1= 6.00
Program Evaluation and Review Technique (PERT)
• Distribusi dari waktu penyelesaian proyek, Te, mengikuti distribusi normal, sehingga bisa dihitung peluang penyelesaian proyek diluar waktu Te. • Misalkan ingin diketahui berapa peluang proyek berumur 27 hari, maka dengan rumus : Z=
Ts − Te 27 − 29 = =− 0.82 Vp 6
Program Evaluation and Review Technique (PERT) • Dengan demikian Z= -0,82 bisa dicari peluangnya (lihat tabel distribusi normal baku), yakni 21%. • Misalnya lagi, dicari umur proyek yang ditargetkan bila diketahui peluangnya. Misalkan peluangnya 95%, maka nilai Z yang bersesuaian adalah 1,645. dapat dicari nilai Ts:
Hitunglah waktu rata-rata dan variansi dari perkiraan durasi pekerjaan – pekerjaan di atas !
Kode A.1
Keg
w. optimis
w. plg mgkn
w. pesimis
Predesessor
Persiapan
A.1.1
A
15
25
30
-
A.1.2
B
20
22
28
-
A.1.3
C
3
7
10
-
A.2
Aktivitas Inti
A.2.1
D
2
5
8
A
A.2.2
E
6
6
8
B, C
A.2.3
F
9
10
11
B, C
A.2.4
G
4
5
6
B, C
A.2.5
H
10
15
18
C
A.3
Penyelesaian (Finishing)
A.3.1
I
3
8
15
G, H
A.3.2
J
8
9
11
D, E
1.
Hitung waktu rata-rata masing-masing pekerjaan !
2.
Hitung juga variansi waktu masing-masing pekerjaan !
3.
Berapakah umur proyek dengan probabilitas 90% ?
PERT Conclusion
PERT : ANOTHER EXAMPLE
