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Project Management Operations Management 2 Project Management Topic 6

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Project Management
Topic 6
Prof. Upendra Kachru

Project
A Project is a unique venture with a beginning and an end, undertaken by people: To meet established goals With defined constraints of time, resources and quality.

Prof. Upendra Kachru

Operations Management

Project Management

It is
―…the application of knowledge, skills, tools, and techniques to project activities to meet project requirements.‖

Prof. Upendra Kachru

Operations Management

Objectives of PM
• Completing the project on time • Completing the project within the budget and within the resources available • Completing the defined work within specifications at a quality level that is appropriate for the success of the project • Using assigned resources effectively and efficiently

Prof. Upendra Kachru

Operations Management

Project Management Objectives expressed Mathematically
Project Management objective of optimizing system implementation can be expressed as a mathematical equality:
 C = f (P, T, S)

 Where:
• • •

‘C’ is cost;
‘P’ is performance; ‘T’ is time, and ‘S’ is scope.

Here Cost is a function of Performance, time and scope
Prof. Upendra Kachru

Operations Management

Project Life Cycle
There are many different phases a project goes through during its lifecycle.
 Every project begins as a concept. The project team must have a clear understanding of the concept.  With the concept clearly defined, it must formalize the definition of the job before doing any work.  Once the project is defined, you can plan how to do the work.  Then you have to execute the project. The team can begin work.  Finally, there has to be a closeout. This is an audit. The point is to learn something from what you just did.

Prof. Upendra Kachru

Operations Management

Each phase has distinctive elements that differ from other

phases.
 They are natural points to reassess the project progress so as to make changes going forward or terminate the project if necessary.  Use of phases provides extra control for the achievement of primary deliverables.

Prof. Upendra Kachru

Operations Management

Prof. Upendra Kachru

Operations Management

Plan Logistic Plan

Contents Materials and equipment required, including transportation, warehousing and site arrival sequence, and as appropriate, acquisition of land for structures. Procurement and contracting events for obtaining projects goods and services Recruitment, training and personnel placement activities.

Procurement Plan Manpower Plan

Financial Plan
Construction Plan Contracting Plan Evaluation Plan

Sequence for commitment of founds and timing of project expenditures.
Preparation of work packages and scheduling activities leading to the aware of contracts. Preparation of work packages and scheduling activities leading to the award of contracts. Data collection activities and timing of review actions.

Prof. Upendra Kachru

Operations Management

Penalties

At the end of the planning phase these must all be frozen.
Prof. Upendra Kachru

Operations Management

Project Management Basics

The Pain Curve

Prof. Upendra Kachru

Operations Management

You should by now have:
 Objectives defined by the metric parameters of:
 Quality (Features)  Cost (Budget)  Time (Schedule)

 And operations within the envelope of:
 Requirements – satisfying customer and stake holder priorities  Scope – what is to be included and what is to be excluded  Constraints – the limiting factors that affect the project  Assumptions – the planning factors affected by risk.

Prof. Upendra Kachru

Operations Management

Work Breakdown Structure (WBS)
At the heart of every project planning system is the project Work Breakdown Structure (WBS). WBS a hierarchical approach to defining project work components. The idea behind the WBS is simple: You can subdivide a complicated task into smaller tasks. The breakdown is continued until a work package level is reached which is small enough for detailed planning and cannot be further subdivided.

Prof. Upendra Kachru

Operations Management

Work Breakdown Structure (WBS) What does it do?
The WBS defines the project scope.

The WBS reflects as accurately as possible the physical project to be completed. It is a detailed breakdown of the overall project into component parts called work packages. It does this by identifying all the tasks that must be performed in order to achieve the project objectives and defines the project in a structured format.

Prof. Upendra Kachru

Operations Management

Work Breakdown Structure (WBS)
The typical WBS has three to six levels.

Prof. Upendra Kachru

Operations Management

Work Breakdown Structure (WBS)
Program represents the total scope for the project team. This is the primary level for measuring earned value. Project identifies the disciplines identified after scoping to be involved in the project delivery. This is the ―Cost Account‖ level at which actual costs are accumulated and the lowest level for assessing earned value. Tasks: This level identifies the resources that are scheduled to perform tasks. It is the project activity level at which cost estimates are prepared and time-phased budgets are prepared.

Prof. Upendra Kachru

Operations Management

Work Breakdown Structure (WBS)
Subtasks extend the WBS to a level of detail necessary to reflect the complexity of the work scope. Work Package: A deliverable or project work component at the lowest level of each branch of the work breakdown structure. The work package includes the schedule activities and schedule milestones required to complete the work package deliverable or project work component. Level of Work Effort: This is work that effects many of the activities of the project and must be done in the project, but it is work that is not connected to any one task.

Prof. Upendra Kachru

Operations Management

Each work package is a complete entity, separate and distinct from all other elements and under well-defined management responsibility. All the facilities and task requirements to build the facilities, or the contracts required to complete construction of the facilities are identified.

Work Packages
Prof. Upendra Kachru

   

Completion is measureable Each Activity has a deliverable Time and cost can be easily estimated Work assignments are independent
Operations Management

Work Breakdown Structure (WBS)
Two principles are particularly important to determine these levels:
 Each part of the WBS should be subdivide to the number of levels useful for managing the project and  No effort should be made to extend the WBS to the same number of levels for all project tasks.

Based upon the project scope, constraints and assumption review the steps/tasks and modify as necessary to describe the work to produce the objective.
 Add new steps and/or tasks,  Remove unnecessary steps and/or tasks,  Merge steps and/or tasks.
Prof. Upendra Kachru

Operations Management

WBS for Garden Project
The background of the project is that Bhan Farms rents its gardens during the marriage season for marriage celebrations. Normally, during the season the garden is fully booked.

The old occupant vacates the premises by 9.00 AM and the new occupant is handed over the garden by noon.
The garden has to be cleaned and trimmed before it is handed over to the next occupant.
Prof. Upendra Kachru

Operations Management

Project - Garden
As you can see, each work package is a complete entity a coding structure is established for each element of the WBS.

Prof. Upendra Kachru

Operations Management

Alternative Work Breakdown Structures
In addition to WBS based on the physical structure, alternative Work Breakdown Structures can be developed for a project depending upon the requirements.
       Deliverables Phase By functional or technological disciplines Organizational structure (functional departments) Systems or subsystems Vendor Responsibilities Physical location
Operations Management

Prof. Upendra Kachru

WBS satisfies both functional and project requirements by assigning responsibilities.

Prof. Upendra Kachru

Operations Management

Project Schedules
Scheduling is a major tool used to manage projects. It puts into perspective the shared understanding of what the project is supposed to accomplish and the Work Breakdown Structure (WBS).

Prof. Upendra Kachru

Operations Management

Description of Schedules System Schedules or Overall Schedules or Master Project Schedules.

Purpose of Schedules Comprises of major system/components of the project. Identifies primary milestones to be achieved. Helps integrate inputs-outputs and resources to achieve overall project objectives. Prepared for each contractor, vendor or functional department. Helps establish resource requirements and commitments so that maximum throughout is achieved. Helps set targets for different agencies and monitor their work, cost and time. Helps determining payment schedules.

i)

ii)

Resource Schedules/Agency Schedules /Functional Schedules.

Input-output Schedules/Work iii) Package Schedules/ Production Schedules.

Helps list each and every input and output like drawing, equipment, etc, so that these can be tracked for completion as well adherence to stipulated time/cost /work targets.

Classification of Schedules
Prof. Upendra Kachru

Operations Management

Waterfall (Sequential) Style – Use when a phase can only start after the previous one has finished Overlapping – Use when phases can start before the previous is finished, often used with schedule compression techniques, but does increase risk and possible rework Iterative – Used when planning is done only one phase at a time and planning for the next is dependent upon the current phase and its deliverables

Master Project Schedules
Prof. Upendra Kachru

Operations Management

Network Representation

There are basically two methods of scheduling, the Critical Path Method (CPM) and the Program Evaluation and Review Technique (PERT). Both the techniques identify how to complete the total project in the minimum time. Critical Path is defined as the longest series of activities (that can‘t be done in parallel) and which therefore govern how early the project can be completed.
Prof. Upendra Kachru

Operations Management

Critical Path Method
The critical path is of great importance in Project Management as it determines whether or not a deadline, which is imposed on most projects, can be met.
• It helps identify which activities will determine the end date. • It also helps guide how the project should be managed. • Knowing where the critical path is in a project allows one to determine the impact on the project of a scope or priority change. • You know which activities will be impacted most heavily and what might need to be done to regain lost time. • In addition, managers can make informed decisions when one can tell them the impact of changes to the project.

Thus, CPM can be an invaluable tool, when used properly.
Prof. Upendra Kachru

Operations Management

Network Notations

CPM and PERT, both use ‘arrow diagrams‘ to capture the sequential and parallel relationships among project activities. To show the sequence in which work is performed, In both these diagrams task A is done before B, while task C is done in parallel with them. The network in the left half shows the work or activity as a box or node, and the arrows show the sequence in which the work is performed. Events are not shown in activity-on-node networks. On the right, the arrow represents the work being done and the circle represents an event. Events are assigned numbers.
Prof. Upendra Kachru

Operations Management

Prof. Upendra Kachru

Operations Management

Dummy Activities

Dummy activities are those activities, which consume no time. However, these are added in the network to satisfy precedence relationships.

Prof. Upendra Kachru

Operations Management

Task Precedence Task

A -

B -

C A

D B

E A, B

Prof. Upendra Kachru

Operations Management

Fulkerson rules determine the numbering sequence. These rules are used for numbering the events on a network:
a) Start with the initial event. b) This event will have arrow(s) coming out of it and none will enter it. Number this ―I‖—it is the initial event. In any network, there will be only one initial event. c) Delete all arrows emerging out of the event already numbered. This will create at least one more initial-event. d) Number these new events as ―2, 3…‖ e) Repeat step (c) till an event is obtained from which there is no arrow emerging. This is the end-event.

Fulkerson Rules
Prof. Upendra Kachru

Operations Management

Once you number events, prepare a list of all activities required to complete the project. Decide their time relationship. Represent each activity by an arrow. Determine the precedence relationship (logical order) of all activities. For this, use these three questions for each activity:
•
•

•

Which activity precedes this activity? This answers which activities, must be completed before the start of activity under consideration. Which activity follows this activity? The answer would show activities that cannot start before completion of the activity under consideration. Which activity should take place simultaneously with this activity? This would be a list of activities, which should be performed simultaneously while the activity under consideration is being performed. It would also provide guidance about the use of dummy activities, if any.

Prof. Upendra Kachru

Operations Management

Number each node as per Fulkerson rule. Check the correctness of the number, using following guidelines:
 Number at the head of any a row is always greater than the node number at its tail.  No node is numbered until its all-preceding events are numbered.  There is only one starting and one finishing node.  All activities are uniquely represented by one starting and one finishing event.  There is no duplicate number for a number.

Prof. Upendra Kachru

Operations Management

Garden Project
Let us discuss the Garden project for which we developed the WBS. Mr. Bhan was interested how early the cleaning-up and preparation of the garden can be completed so that the garden could be handed over to the new occupant. This small garden project might be thought of as having three phases:
 Preparation,  Execution,  Cleanup.

Prof. Upendra Kachru

Operations Management

Garden Project (contd.)
 There are three preparation tasks:
 Pick up trash,  Fill fuel in equipment, and  Get out hedge clipper etc.

 The cleanup tasks include:
 Bag the grass,  Collect trash, and  To disposal.

Prof. Upendra Kachru

Operations Management

In making this schedule diagram, there are two rules to follow:
 The first is to go ahead and schedule as if it were possible to get help. This is especially important in most work settings.  The second is to keep all times in the same units. It is always possible to convert the unit as a last step. For example, in this schedule time has been given in minutes.

Prof. Upendra Kachru

Operations Management

Garden Project

Prof. Upendra Kachru

Operations Management

For the Garden project example, we will use node notations. Let us examine the node boxes in the schedule. Each box has the notation ES, LS, EF, LF, and DU. These notations mean the following:
     ES = Early Start LS = Late Start EF = Early Finish LF = Late Finish DU = Duration (of the task)

Prof. Upendra Kachru

Operations Management

Activity Chart
Activity A B C D E F Description Pick up Trash Fill Fuel Fetch Hedge Clipper Trim Weeds Mow Front Edge Side walk A, B A, B A, B A-D A-E A-F Predecessor Activity Network Path 15 5 5 30 45 15 Time (Min.)

G
H I J K

Trim Hedge
Mow Back Yard Bag Grass Collect Trash To Disposal

C
E H, D, F, G H, D, F, G I, J

C-G
A-E-H A-E-H-I A-E-H-I A-E-H-I-K

30
30 30 15 45

Prof. Upendra Kachru

Operations Management

Computing the network

In order to compute network start and finish times, only two rules apply to all networks.
 Rule 1: Before a task can begin, all tasks preceding it must be completed.  Rule 2: Arrows denote logical precedence.

Start from the starting event, Early Start (ES) for the first event (i.e., A) is zero, as the starting time is zero.

Prof. Upendra Kachru

Operations Management

Computing the network
For the next events, the activity times are the summation for each possible path, leading from the starting event to the given event. The largest sum is the earliest expected time for that event. For the scheduling computations in the Garden project, for example, we assume that it starts at time = zero, it can finish as early as fifteen minutes later. Thus, we can enter 15 in the cell labeled EF. Putting fuel in the grass mower and collecting the hedge clipper and other equipment takes only five minutes each. The logic of the diagram says that both of these tasks must be completed before we can begin trimming weeds, cutting the front grass, and edging the sidewalk.

Prof. Upendra Kachru

Operations Management

The earliest finish time for activities, P and Q, is calculated as:
EFQ = Max {ESP + tPQ} Where ESP = Earliest Start time for activity ‘P’ (predecessor) tPQ = Expected completion time for activity P – Q

In our Garden project example, for the initial events:
EFA = 0 +15 = 15 minutes EFB = 0 + 5 = 5 minutes EFC = 0 + 5 = 5 minutes

The Earliest Start (ES) time for an activity is the Earliest Finish (EF) time of the immediately preceding activity.
Prof. Upendra Kachru

Operations Management

If we consider Activity D in our example, there are two preceding activities. Activity B has an EF of 5 minutes while Activity A has an EF of 15 minutes. For activities with more than one preceding activity, ES is the largest of the EF of the preceding activities. This is the time at which an event can occur without delaying the scheduled completion date of the project, if all succeeding events are completed as per plan. We use backward pass or backward calculation from the finishing point of the network. The cleanup task takes fifteen minutes, whereas the fueling-up activity takes only five minutes. How soon can the following activities start? Not until the cleanup has been finished, since it is the longest of the preceding activities. The Early Finish for cleanup becomes the Early Start for the next three tasks.
Prof. Upendra Kachru

Operations Management

The longest path determines how early subsequent tasks can start. Following this rule, we can fill in Earliest Start times for each task. The project will take a total of 165 minutes to complete, if all work is conducted exactly as shown.
       
Prof. Upendra Kachru

EFD = Max {ESA + 30) = 15 + 30 = 45 minutes EFE = 15 +45 = 60 minutes EFF = 15 +15 = 30 minutes EFG = Max {ESC + 30) = 5 + 30 = 35 minutes EFH = 60 +30 = 90 minutes EFI = 90 +30 = 120 minutes EFJ = 90 +15 = 105 minutes EFK = 120 +45 = 165 minutes Operations Management

Similarly, for the other activities the EF can be calculated:

To obtain the latest start and latest finish times, we must work backward form the finish node. The Latest Finish time (LF) for an activity is the latest start time of the activity immediately following it. For activities with more than one activity immediately following, LF is the earliest of the latest start times of those activities. The Latest Start time (LS) for an activity equals it latest finish time minus its estimated duration, ‗t‘.
LSP = LFP - tP

In our example:
LSK = LFK – tK = 165 - 45 = 120 minutes

If activity ‗K‘ must start no later than 120 minutes, activities ‗I‘ and ‗J‘ must finish no later than 120 minutes. Therefore, LFI = 120 minutes and; LFJ = 120 minutes
LSJ = LFJ – tJ = 120 - 15 = 105 minutes LSI = LFI – tI = 120 - 30 = 90 minutes
Prof. Upendra Kachru

Operations Management

Similarly, LFH = 90 minutes as activity ‗I‘ has to start by 90 minutes, for the total time to add up to 145 minutes. If activity ‗I‘ is delayed, the project cannot be completed by 145 minutes. Other predecessor activities to ‗I‘ are ‗D‘, ‗F‘ and ‗G‘. Therefore, LFD = 90 minutes, LFF = 90 minutes, LFG= 90 minutes while the predecessor activity for ‗E‘ is activity ‗H‘ and LFE = 60 minutes
LSH = LFH – tH = 90 - 30 = 60 minutes LSG = LFG – tG = 90 - 30 = 60 minutes LSF = LFF – tF = 90 - 15 = 75 minutes LSE = LFE – tE = 60 - 45 = 15 minutes LSD = LFD – tD = 90 - 30 = 60 minutes

The predecessor activity for ‗C‘ is ‗G‘. The LFC is therefore 60 minutes, and the predecessor activities for ‗A‘ and ‗B‘ are ‗D‘, ‗E‘ and ‗F‘. Therefore, LFA = LFB and is 15 minutes.
LSC = LFC – tC = 60 - 5 = 55 minutes LSB = LFB – tB = 15 - 5 = 10 minutes LSA = LFA – tA = 15 -15 = 0 minutes
Prof. Upendra Kachru

Operations Management

Garden Project

Prof. Upendra Kachru

Operations Management

Slack

There are two types of activity slack: Total slack for an activity is a function of the performance of activities leading to it. It can be calculated in one of two ways for any activity:
S = LS – ES or S = LF - EF

Free slack is the amount of time that an activity‘s earliest finish time can be delayed without delaying the earliest start time of any activity immediately following it. The start date for an activity with free slack can be delayed without affecting the schedules of other activities.

Prof. Upendra Kachru

Operations Management

Critical Path & Slack
Activity A Description Pick up Trash ES 0 EF 15 LS 0 LF 15 Slack 0

B
C D

Fill Fuel
Fetch Hedge Clipper Trim Weeds

0
0 15

5
5 45

10
55 60

15
60 90

10
10 45

E
F G H I J K

Mow Front
Edge Side walk Trim Hedge Mow Back Yard Bag Grass Collect Trash To Disposal

15
15 5 60 90 90 120

60
30 35 90 120 105 165

15
75 60 60 90 105 120

60
90 90 90 120 120 165

0
60 55 0 0 15 0

Prof. Upendra Kachru

Operations Management

Crashing
Project Management has as its objective optimizing a system. A project can often be completed earlier than scheduled by hiring more workers or running extra shifts or using additional equipment. Such actions could be advantageous if savings or additional revenues accrue from completing the project early. Feasible Activity Time-Cost Trade-Off Points: represent the various combinations of minimum direct costs and their corresponding least timings for one individual activity only. The method of choosing the schedule, leads to the least variation in resource requirements. This is also called crashing.

Prof. Upendra Kachru

Operations Management

Activity Time-Cost Tradeoff Curve

Additional Cost for Crashing 1000

Additional Cost (Rs.)

Crash Cost 500

Normal Cost 0 0

5

10

15

20

Project Completion Time (t)
Prof. Upendra Kachru

Operations Management

Crashing the Garden Project

For example, in the Garden project the critical path is A-E-H-I-K. You would damage the mower if you start mowing without removing the trash. So, activity ‗A‘ would be difficult to crash. However, you can mow the front lawn and the back lawn simultaneously, if You invest in an additional mower, and Add an additional man to run the second lawn mower. Suppose the cost of renting the lawn mower is Rs. 250.00 each day and the cost of an extra gardener is Rs. 150.00. By crashing activity E, we can reduce the total time to 135 minutes. However, we would be able to do this at a crash cost of Rs. 400.00.
Prof. Upendra Kachru

Operations Management

Crashing the Garden Project
Activity A B C D Description Pick up Trash Fill Fuel Fetch Hedge Clipper Trim Weeds ES 0 0 0 15 EF 15 5 5 45 LS 0 10 10 30 LF 15 15 15 60 Slack 0 10 10 15

E
F G H I J K

Mow Front
Edge Side walk Trim Hedge Mow Back Yard Bag Grass Collect Trash To Disposal

15
15 5 15 60 60 90

60
30 35 45 90 75 135

15
45 30 15 60 75 90

60
60 60 60 90 90 135

0
30 25 15 0 15 0

Prof. Upendra Kachru

Operations Management

Crashing the Garden Project

Prof. Upendra Kachru

Operations Management

Program Evaluation and Review Technique (PERT)
For single-time estimate CPM and PERT charts remain exactly the same. CPM and PERT differ in that PERT can also use probability distributions. PERT uses the beta probability distribution. The variability associated with activity performance times is considered for computing completion time probabilities only. The beta distribution, unlike the normal probability distribution, allows the most likely time estimate not to be symmetrical. By obtaining three time estimates for each activity, it is possible to calculate the excepted duration of each activity and the standard deviation of that duration. Those values can then be used to determine an expected completion time for the project, as well as the probability of completing the project within a given time period.
Prof. Upendra Kachru

Operations Management

The three time estimates used to calculate expected activity time are:
Optimistic time the shortest time the activity will reasonably take Most likely time (m) the time this activity would take most of the time. Pessimistic time (b) the longest time the activity would be expected to take

Using these three values, it is possible to calculate the expected duration of an activity. The formula is given as:
te = (a +4m + b) / 6

The variance of activity duration is given by the formula:
σ2 = [(b-a) / 6]2 where: ‘te‘ is the expected time ‗σ2‘ is the variance ‘a‘ is the optimistic time estimate ‗m‘ is the most likely time estimate ‗b‘ is the pessimistic time estimate
Prof. Upendra Kachru

Operations Management

For determining the probable dates of completion, the network is drawn and variance for all the events falling on the critical path is computed. The variance of a particular event is calculated, assuming zero variance for initial event and then adding the variance of the activity (or of activities) on the critical path up to the event.

Prof. Upendra Kachru

Operations Management

PERT Chart for Garden Project
Activity Description Optimistic Time (a) Pessimistic Time (b) Most Likely Time (m) Expected Time (te) Variance (σ2)

A B C

Pick up Trash
Fill Fuel Fetch Hedge Clipper

12 5 3

18 5 10

15 5 5

15 5 5.5

1.00 0 0.25

D
E F G H I J K

Trim Weeds
Mow Front Edge Side walk Trim Hedge

30
40 14 30 25 20 40

30
55 16 35 40 30 15 50

30
45 15 30 30 30 15 45

30
45.83 15 30.83 30.83 28.33 15 45

0
6.25 0.026 0.69 6.25 2.76 0 2.76

Mow Back Yard
Bag Grass To Disposal

Collect Trash 15

Prof. Upendra Kachru

Operations Management

Notice in some case that all three time estimates are the same. Those are activities that will always take a set amount of time, without any variation. The expected time for each activity is calculated, using the formula introduced previously. For example, the expected time for activity ‗C‘ will be
te = (a +4m + b) / 6 = (3 + 4*5 + 10) / 6 = 5.5 minutes

The variance in that completion time will be
σ 2 = [(b-a) / 6]2 = [(10 – 7)/ 6] 2= 0.25 minutes

To determine the probability of completing the critical-path activities within a certain time, the completion time is assumed to be normally distributed. Although a large number of activities may not be on the critical path, the normal distribution is still a good approximation.
Prof. Upendra Kachru

Operations Management

The probability of completion of the project, by time ‗TS‘, is determined by using the normal probability table. The variance and statistical-mean-time for a particular event can be calculated using the control Limit Theorem, which states:
Event Expected Duration = TE = (te) 1-2 + (te) 2-3+…. Variance of time for the event = VTE = Vt1-2 + Vt2-3+…

In case of PERT network charts, ‗z‘, the standard deviation, can be calculated with the Formula:
z = (TS – TE) / (VTE) ½

Where z = units in terms of standard deviation, TS = the scheduled time for the completion of the event, and TE = the event meantime computed using Control Limit Theorem like above.

Suppose Mr. Bhan wants to know the expected activity times of the Garden project. He is keen to determine that if he gets possession of the garden by 9.00 AM, what is the probability the garden will be ready by noon?

Prof. Upendra Kachru

Operations Management

The times required to prepare the garden will be the total of the critical path activities that consist of A, E, H, I and K.
TE = (te) 1-2 + (te) 2-3+…= 15 + 45.83 + 30.83 + 28.33 + 45 = 164.99 minutes

This gives an expected project completion time of 164.99 minutes. The sum of variances for activities on the critical path will be:
VTE = Vt1-2 + Vt2-3+…= 1 + 6.25 + 6.25 + 2.76 + 2.76 = 19.02 minutes

Then the ‗z‘ value will be
z = (TS – TE) / (VTE) ½ = (180 – 164.99) / √19.02 = 15.01/4.36 =3.442

Referring to the normal probability distribution table, the probability corresponding to a ‗z‘ value of 3.442 is larger than 99.99 per cent. Mr. Bhan can rest assured that if he gets the activities started at 9.00 AM, he will be in a position to hand over the premises to the new occupant by noon.
Prof. Upendra Kachru

Operations Management

Joint Probabilities and Multiple Critical Paths
When there are two or more critical paths simultaneously all their activities can be placed under two categories:
Category I – includes all those activities which are common for all the critical paths, and Category II – includes those activities, which are different for different critical paths.

For category II activities try various combinations and use your judgment. Further, check if a path that is not critical may have greater variance than the critical path does. If it does, it is possible for that path to end up being critical before the project is completed. Therefore, we need to consider the ‗z‘ values of various combinations in the project.

Prof. Upendra Kachru

Operations Management

Project Planning Scheduling and Control System (PPSCS)
Just like WBS is the heart of every project planning system, project planning, scheduling and control system (PPSCS) is the backbone of Project Management. 1. It enables time phasing of the project activities/ work packages. 2. It also develops the resource requirements and allocation plan as well as the cash-flow plan. 3. It identifies specific milestone events. 4. It is a prerequisite for monitoring of the project at various levels. By using the PPSCS system, specific responsibilities for time and cost can be assigned to those concerned with managing the project.
Prof. Upendra Kachru

Operations Management

Control Systems
The owner‘s and their contractor‘s point of view design on project planning and control system is different. The owner‘ control system is often known as task oriented system where as the contractor‘s system is known as resource oriented system.
 Task Oriented System: In a task oriented planning and control system, the objective is to minimize time delays.  Resource Oriented System: A turnkey contractor, on the other hand, is more focused ensuring fullest utilization of his resources. Fullest utilization of the resources is the overriding consideration in the design of the control system.

Prof. Upendra Kachru

Operations Management

The different elements of the conceptual PPSCS model include: (a) Objective, (b) Planning, (c) Scheduling, (d) Implementation (e) Monitoring, (f) Updating, (g) Progress Reporting, and (h) Control.

Control Systems

Prof. Upendra Kachru

Operations Management

Planning Scheduling & Monitoring System

Prof. Upendra Kachru

Operations Management

Multilevel Scheduling Systems
In multilevel scheduling systems, master networks for the top management are prepared to coordinate the various functional plans, to identify the interface events and to provide the top management with a means to authorize and control work and expenditure. Though planning the network is based on identifying the longest timeconsuming path (or the path with zero slack), this very often does not remain the critical path for the project. What often happens as the project progresses is that some activity not on the critical path becomes delayed to such a degree that it extends the entire project. It is important to determine the critical path and the expected time values along the critical path, but ultimately events need to be monitored constantly to determine project completion time.

Prof. Upendra Kachru

Operations Management

Forecast control
Read ‗Using Project Software‘ from the text book.

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Prof. Upendra Kachru

Operations Management

Operations Management (2)

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posted:10/21/2009
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