scheduling by suchenfz

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									 Lecture 9   Project Scheduling


Time



                           Events

         Resources




             Winter 2011            1
                    Project Scheduling

     Once the project is defined, the schedule becomes the most
     visible project document.
     Developing a schedule is an iterative process. Remember the
     triangle.

                                              Resource
                                             Availability
   Features

•Task Description    Preliminary             Working
•Resource needs        Linking               Schedule
                                      No                        No
                                                 Time
                                                             Final
                                           Yes
                                                            Schedule

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          Control Documents support key factors


                                                PFSD
                          Product
The FSD answers the      Features-F
What?                                            CG&S
The CG&S answers the
How?
                                                FSD
And the Schedule
answers the When?          C=F/T

      Development      Schedule
                                       Development      Final
                                                        Project
        time-T                           cost-C         Reports



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     The key parameters of Development

    Trade offs between the key product development
    factors.
                 Product
C=F/T          Features-F




  Development                     Development
    time-T                          cost-C


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 Murphy’s Law of Development
• A project can be done;
   – quickly,
   – inexpensively,
   – or well.
• One can pick any two of the three
  variables at the same time, but not all
  three.
   – (informally it’s fast, cheap, or good)

• Inherent trade-off between:
Speed Cost Quality



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           Project Scheduling
When does a team develop a Project Schedule?

It doesn’t make too much sense to do a detailed schedule
before the project definition is complete. However, a rough
schedule with approximate milestones is generally created
early in the concept development phase. This preliminary
schedule is used for project justification and project pipeline
planning.
Once the project passes through the system level design
checkpoint, and project level feasibility is proven, then the
detailed schedule is completed. This coincides with the
addition of project resources from other functional areas, and
the authorization of large project funds to complete the
project.
The detailed schedule becomes a contract between the
development team and the company. Contracts and schedules
can be modified over time, but both require the explicit
consent of both parties.
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    Project Scheduling
         8 Steps to complete a schedule

Step 1

•   The first step is to develop a task description
    list. This is list of all the tasks that you can think
    of that will be necessary to complete the project.

•   It is very important not to skip over some of the
    more common tasks, such as system integration or
    testing time.



                      Winter 2011                        7
Project Scheduling

Practice assignment. Develop a Gantt Chart for the following
project;

Fixing dinner      The dinner will include a tossed salad, mushroom and rice
casserole, baked salmon, and rolls.
  Step 1. Major activities
                     •wash and cut vegetables for the salad
                     •toss the salad
                     •set the table
                     •prepare the mushrooms
                     •cook the mushrooms
                     •mix rice with casserole ingredients
                     •bake the casserole 350 degrees
                     •prepare the salmon
                     •bake the salmon
                     •prepare the rolls
                     •serve the dinner



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     Project Scheduling
Step 2

•   Next you make a first pass at the resource
    requirements to complete each task.
•   The resource requirements need to consider both
    time and the number of people available.
•   This will be hard for some of your projects,
    because most of you don’t have any prior
    experience to give you a baseline.
•   Don’t estimate too tightly: allow for the
    unexpected.
•   You will also have to make some fundamental
    assumptions about the project.

                    Winter 2011                   9
 Project Scheduling

    Fixing dinner      The dinner will include a tossed salad, mushroom
and rice casserole, baked salmon, and rolls.

Assumptions: casserole requires the mushrooms to be precooked. We can
cook both the casserole and the salmon in the same oven. We have only
two people to complete the assignment

Step 2. Assign resource requirements
Major activities and times
    •wash and cut vegetables for the salad--15 minutes
    •toss the salad--5 minutes
    •set the table -- 8 minutes
    •prepare the mushrooms– 5 minutes
    •Precook the mushrooms– 10 minutes
    •mix casserole ingredients— 10 minutes
    •bake the casserole 350 degrees--25 minutes
    •prepare the salmon -- 10 minutes
    •bake the salmon -- 20 minutes
    •prepare the rolls -- 5 minutes
    •serve the dinner -- 5 minutes

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  Project Scheduling
Step 3

•The third step is to identify linkages between the
various tasks.
•Certain tasks are independent and can be started at
any time.
•Most tasks require the completion of other
activities before they can be started.
•Some tasks will have multiple linkages.
•You may want to use a ―task structure matrix‖ to
determine linkages.




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Three
Fundamental
Activity
Relationships

 Example: Kodak Cheetah
 Microfilm Cartridge



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   Step 3. Identify the dependencies between
   activities.



   •     # Task                      Time   Dependencies
   1.    wash and cut vegies         15m    none
   2.    set the table               10m    none
   3.    Prepare the mushrooms       5m     none
   4.    precook the mushrooms       10m    3
   5.    mix casserole ingredients   10m    4
   6.    bake the casserole          25m    5,12
   7.    prepare the salmon          10m    none
   8.    bake the salmon             20m    7, 12
   9.    prepare the rolls           5m     none
   10.   serve the dinner            5m     6,11,2,8,9
   11.   toss the salad              5m     1
   12.   heat the oven               10m    none




What assumptions are you making about available resources?
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    Project Scheduling
Step 4

•    Identify the major checkpoint activities that
     will require the completion and demonstration of
     project status.


Example

Check if Casserole and Salmon are done.




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     Many activities may need to come together
     for the checkpoint meetings.


    Activities                   Checkpoint
A                                Meeting
                                                1
                                              Proceed to
                                              next phase
B
C
    E
                                   2
D                                Redirect
                                 Project

                                                    3
                                               Cancel
    Development Phase                          Project


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Project Scheduling

Step 5

•   Develop the preliminary schedule. There are
    many software programs, such as Microsoft
    Project, that can be used to actually complete
    the schedule.




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                    Gantt Chart for Dinner exercise
                              10 min      20 min     30 min   40 min   50 min   60 min
* Wash and cut
vegies

* Toss the salad

* Prepare rolls

* Set the table

* Serve dinner
* Prepare
mushrooms
* Precook
mushrooms
* Mix casserole

* Cook Casserole


* Cook Salmon

* Prepare Salmon

* Preheat oven




                   Person 1            Person 2
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              PERT and CPM Charts
                4           2             8



      Start          3                4            Finish




                 6              5
                                                 activity and
• Simple network diagrams                 days   duration
  are easy to understand.
• We cannot represent the                 activity precedence
  coupled/iterative task
  relationships.



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   Project Scheduling
Step 6
•Analyze the results. Most schedules require many passes to
balance the tasks, resources, and requirements. This is just
like the project triangle. If the project schedule doesn’t
meet the market requirements, then the project team must
either modify the number of available resources, or reduce
the scope of the project.

•In the case of your project, it is important to identify what
degrees of freedom are available. The project end point is
fixed. Therefore, you can only change the resources, (the
amount of time that the team will commit to this project), or
the scope of the development effort, (the features that your
product will have).



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       Step 3. What changes if you only have one person?

               You have to determine a new sequence of task completion.




•     # Task                                   Time    Dependencies
1.    Heat the oven                  10m               none
2.    Prepare mushrooms              5m                none
3.    Precook the mushrooms          10m               2
4.    mix casserole ingredients      10m               3
5.    bake the casserole             25m               4
6.    prepare the salmon             10m               4
7.    bake the salmon                20m               6
8.    Wash and cut vegies            15m               6
9.    Toss the Salad                 5m                8
10.   Set the table                  10m               9
11.   Prepare the rolls              5m                10
12.   Serve the dinner               5m                5, 7, 9, 10, 11



                                           minutes!!
                Now the activity takes 752011
                                    Winter                                20
  Project Scheduling

•What can you do to reduce the time to complete the
dinner?
•Could 3 or more people help?
•If you had more time to prepare, how could you shorten
the schedule?




                      Winter 2011                         21
    Project Scheduling
Step 7

•   Identify the Critical Path, the series of
    tasks that have no slack time associated with
    their completion. Then look for ways to do
    more in parallel to shorten the time. The
    perfect schedule has all paths at their
    critical points.




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                            Critical Path                               Slack time
         Critical Path
                         10 min     20 min   30 min   40 min   50 min        60 min
* Wash and cut
vegies

* Toss the salad

* Prepare rolls

* Set the table

* Serve dinner
* Prepare
mushrooms
* Precook
mushrooms
* Mix casserole

* Cook Casserole


* Cook Salmon

* Prepare Salmon

* Preheat oven




                              Winter 2011                                        23
              PERT and CPM
    (Critical Path Management) Charts
        4        2             8



Start        3             4             Finish




         6           5
                                       activity and
                               days    duration


                               activity precedence

                               critical path




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 Project Scheduling

Step 8

•When the schedule is close to completion, most
smart teams insert into the schedule some
planned slack time for contingencies.




                  Winter 2011                     25
              Project Scheduling

DSM - design structure matrix. Shows serial, coupled,
and parallel tasks

Gantt chart - horizontal time line of the project.
Commonly used to show completion status.

PERT chart - explicitly shows both timing and task
dependencies. The nodes of the chart are the task
descriptions, and the lines show the duration. It is easy
to add critical path identification to the chart.

(In most development projects a person is assigned to
develop and manage the schedule. Most projects with
over 15 people or multiple teams will require a full time
project coordinator.)

                       Winter 2011                          26
           Homework Assignment


•Prepare the “task list” for your actual project.
(Use Microsoft Project to complete the
Schedule for your project.)

• Email a copy of your task list to me before
Thursday’s lecture.

•Review the material in Chapter 16 of Ulrich
and Eppinger




                   Winter 2011                      27
            PERT Chart and Critical Path

A     Receive and Accept Specification               H       Design Mold
B     Concept Generation/Selection                   I       Design Assembly Tooling
C     Design Beta Cartridges                         J       Purchase Assembly Equipment
D     Produce Beta Cartridges                        K       Fabricate Molds
E     Develop Testing Program                        L       Debug Molds
F     Test Beta Cartridges                           M       Certify Cartridge
G     Design Production Cartridge                    N       Initial Production Run



A 2         B 4          C   8       D 8                        G                   L 4


                                                F    2          H          K 10     M 2    N 2

          task                                                   I
                                     E   5

                 A 2                         critical path           14
                                                                           J   6

                  duration (weeks)

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              Design Structure Matrix
     TASK                               A B C D E F G H I J K L M N
Receive and Accept Specification     A A       Sequential
                                               Tasks
Concept Generation/Selection         B   B                Parallel
Design Beta Cartridges               C     C              Tasks
Produce Beta Cartridges              D       D
Develop Testing Program              E         E
                                                                      Coupled
Test Beta Cartridges                 F            F                   Tasks
Design Production Cartridge          G               G
Design Mold                          H                    H
Design Assembly Tooling              I                       I
Purchase Assembly Equipment          J                           J
Fabricate Molds                      K                             K
Debug Molds                          L                               L
Certify Cartridge                    M                                  M
Initial Production Run               N                                     N
      .
                   Example: Kodak Cheetah Microfilm Cartridge


                                     Winter 2011                                29

								
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