THEORIES AND PRACTICE INPROJECT SCHEDULINGSTEPHEN KAMAU UNIVERSITY OF NAIROBI PHD STUDENT IN PROJECT PLANNING

PROJECT SCHEDULEproject management, a schedule consists of a list of a project's terminal elements with intended start and finish dates. Terminal elements are the lowest element in a schedule, which is not further subdivided. Those items are often estimated in terms of resource requirements, budget and duration, linked by dependencies and scheduled. In

WHY SCHEDULE A PROJECT There

are several parties involved in any project (stakeholders). They all need and benefit from project scheduling but from different perspectives. Reasons for project scheduling can be analyzed from a stakeholders perspective Two different perspectives: project managers and owners are analyzed below The need for a project schedule varies and it increases with the increase in size and complexity of the project

WHY SCHEDULE A PROJECTPROJECT MANAGERS PERSPECTIVE1.

Calculate the project completion date: In most construction projects, the general contractor including subcontractors and other team members, is obligated to finish the project by a certain date specified in the contract. The contractor has to make sure that his or her schedule meets this date. Some contracts contain clauses for penalties for finishing the project later than contractually required and/or incentives (financial or other) for finishing earlier.

CONT.2.Calculate the start or end of a specific activity: Specific activities may require special attention, such as ordering and delivering materials or equipment. For instance, the project manager may want special and expensive equipment to be delivered just in time for installation. Longlead items may have to be ordered several months in advance. Delivery of very large items may need coordination or a special permit from the city so that such delivery does not disrupt traffic during rush hour. The schedule must show such important dates.

CONT.3. Coordinate among trades and subcontractors, and expose and adjust conflicts: In a construction project for instance, the general constructor's (GC) role is mostly to coordinate among different subcontractors. The responsibility of the GC may be to allocate the time of use of a resource e.g. a tower crane among subcontractors or just to ensure that adequate work space is available for all subcontractors. These tasks are in addition to coordinating logical relationships such as when a subcontractors activity depends on the completion of another subcontractors activity.

CONT..4. Predict and calculate the cash flow: The timing of an activity has an impact on the cash flow, which may be an important factor for the Project Manager(or the owner) to consider. The Project Manager (or the owner) must know his or her total spending in any month or time period. He or she may delay the start of certain activities, within the available to make sure that the cash flow does not exceed a certain amount.

CONT..5. Improve work efficiency: By properly distributing workers and equipment and having efficient materials management, the Project Manager can save time and money. 6. Serve as an effective project control tool: Project control must have a solid and sound base with which current performance can be compared. Project control is achieved by comparing the actual schedule and budget with the baseline (as-planned) schedule and budget

CONT.7. Evaluate the effect of changes: Change orders are almost inevitable, but well-planned projects may have few or minor change orders. Change orders may come in the form of directive, that is, an order to the project manager to make the change, or request for evaluation before authorization. This change may be an addition, a deletion, or a substitution. Change orders may have an impact on the budget, schedule, or both

CONT.8. Prove delay claims: Project delay claims are common especially in construction projects. Contractors must be able to accurately prove their claims against owners (or other parties) using project schedules. In most cases, only a critical path method (CPM) schedule can prove or disprove a delay claim, which can be millions in amount.

WHY SCHEDULE A PROJECTAN OWNERS/DEVELOPERS PERSPECTIVE1.

Get an idea on projects expected finish date: Before an owner demands that the project manager or general contractor (GC) complete the project by a certain date, he/she needs to make sure that this is a feasible and reasonable date. This date is calculated by a CPM schedule prepared either by the owner or by the designer or other consultant hired by the owner.

CONT..2. Ensure project managers proper planning for timely finish: Owners may demand a project schedule from the prospective or bidding contractor in a construction project. However, it is very important for the owner to review such schedule and make sure that it is reasonably accurate and realistic before awarding the contract.

CONT..3. Predict and calculate the cash flow: The owner is obligated to make timely progress payments to the project management or contractor and other parties along the life of the project. Failure to do so not only may delay the project and/or incur additional cost but it also mayat certain pointbe deemed a breach of contract. A project schedule is an important guide in this.

CONT .3. Serve as an effective project monitoring tool: Both owner and manager must monitor progress of work and compare actual progress (schedule and cost) with the baseline (as-planned) schedule and budget. The manager uses this process to detect and correct any deviation and also to prepare progress payments. The owner uses this process to verify actual work progress and project managements payment requests.

CONT.4. Evaluate the effect of changes: Owners may desire or require change orders. In many instances, owners dont expect or fully appreciate the impact these change orders may have on the schedule and/or budget. A project schedule will help the owner to find out this impact before making a decision regarding such change order.

CONT5. Verify delay claims: Owners use CPM schedules to analyze, verify, and/or dispute managers or contractors delay claims. 6. Other parties involved in the project may also need a CPM schedule, such as the designer, project management consultant, and financial lending institution.

OTHER USES OF PROJECT SCHEDULES:Schedules also help in the following: They provide a basis for monitoring and control project activities. They help in determining how best to allocate resources so you can achieve the project goal. You can figure out where excess resources are available to allocate to other projects. They provide a basis to help you track project progress.

THE PROJECT SCHEDULE REPRESENTS THE TASKS WITH:start and finish dates of each task duration of each task dependencies between tasks (predecessors and successors) a hierarchy organizing the tasks (using Work Breakdown Structure) a graphical Gantt Chart or bar chart showing the date ranges of the tasks as bars over time A network diagram

SCHEDULE INPUTSYou need several types of inputs to create a project schedule: Personal and project calendars Understanding working days, shifts, and resource availability is critical to completing a project schedule. Description of project scope From this, you can determine key start and end dates, major assumptions behind the plan, and key constraints and restrictions.

CONTProject risks needed to make sure there's enough extra time to deal with identified risks and with unidentified risks. Lists of activities and resource requirements Understanding the resource capabilities and experience you have available as well as company holidays and staff vacations will affect the schedule.

SCHEDULING CRITERIAIn order for a project schedule to be healthy, the following criteria must be met (cutting, 2009)The schedule must be constantly updated. y The estimate cost at completion (EAC) value must be equal to the baseline value. y The remaining effort must be appropriately distributed among team members (taking vacations into consideration).y

THE PLACE OF SCHEDULING IN THEPROJECT TRIANGLE

CONT

Source: Stoemmer (2011)

CONT.

According to Stoemmer (2011) , the scheduling process has three main steps: Milestone plan Network diagram gantt chartSource: Stoemmer (2011)

STEPS CONT.

Holohan (2010), list 6 steps to project scheduling:y y y y y y

Step 1: Define the Schedule Activities Step 2: Sequence the Activities Step 3: Estimate the Resources Needed for the Activity Step 4: Estimating the Duration of Each of the Activities Step 5: Schedule Development Step 6: Monitoring and Controlling the Schedule

SCHEDULING TECHNIQUES

Project managers have a variety of tools to develop a project scheduleAction planning for small projects, y Bar charts:y

Gantt Charts and Linked gantt/bar Charts Mile stone charts Activity on arrow network techniques: Project review and evaluation technique (PERT) & Critical Path Method (CPM) Activity on node techniques: precedence network analysis (PNA)

y

Network analysis:

Line of Balance (LOB) y Q Scheduling y Schedule Compression: Crashing & Fast-Trackingy

ACTION PLANNING (FOR SMALL PROJECTS)

Small projects that take a few days and are not complicated in that they contain a few activities can be scheduled using an action plan. E.g. a sales campaign for a product in a city may take the following form of schedule:activity Identify target outlets Develop sales promotion materials designs Print the promotion materials By who Area sales managers Product manager Product manager By when 15 Nov 2011 20 th Nov 2011 30th Nov 2011

GANTT CHARTSIt is a horizontal-bar schedule showing activity start, duration, and completion. It shows the connection between events and the calendar, and provides a graphical analog of the activity duration. The Gantt schedule can illustrate the relationship between work activities having duration, events without duration that indicate a significant completion, and milestones that represent major achievements or decision points.

GANTT CHARTS CONTGantt charts are useful and commonly used to detect the amount of resources needed for one particular project. Adding the resources vertically will produce what is called the resource aggregation. The purpose of this aggregation is to estimate the work production and establishing estimates for manhour and equipment needed.

GANTT CHART

GANTT CHART

THE LINKED GANTT/BAR CHART

Using a linked bar chart, the activities and subsequent items are linked with arrows and lines, specifying the sequence and order of preceding activities. The previous activities are linked one to another to demonstrate that one activity must be completed before the other activity can start.

LINKED BAR CHART

MILESTONE CHARTSMilestone charts are similar to gantt charts but display only major events. They display major milestones. They are used to report status to Management. A milestone chart depicts key events along a timescale. A milestone chart traditionally used triangles to depict a specific event. A milestone on a milestone chart Gantt can depict a specific event or a culmination of events.

MILESTONE CHART

ADVANTAGES OF GANTT CHARTS- It gives an easy and visual idea about the status of the project i.e. is it on time or not. - It can show who's working on what activity - It shows the dependencies of the tasks. - It can easily adapt to changes in the project. - It shows the total cost of the project once resources are integrated - It tells how much, in proportion, of a task is complete - It is easily understood - It is easily created. In most Project Management Software, the project manager just creates the project schedule and the Gantt Chart is created automatically by the software. - It is universally accepted

DISADVANTAGES OF GANTT CHARTS

It can become quite complicated for large projects a Gantt chart does not effectively address the dependencies between jobs (although constraints can be added as vertical lines), dependencies are hard to verify, it is difficult to show two sets of dates when using techniques such as earliest start date and latest start, it is difficult to show slack and critical path without additional notation, changes to the schedule require a redrawing of the chart, several scheduling possibilities cannot be shown in the same chart,

ACTIVITY ON ARROW NETWORKS

These are :Project review and evaluation technique (PERT) y Critical Path Method (CPM)y

CPM AND PERT

Both use Network Diagrams CPM: deterministic PERT: probabilistic CPM: one estimate, PERT, three estimates PERT is infrequently used

CPM

A critical path method (CPM) is a network of events, each one linked to the following activities. Each activity is represented as a node on the network, and connecting lines are drawn to represent the time schedule to complete that activity. A critical path method schedule is completed using the following steps:y y y y y

Identify the activities Determine the sequence of the activities Connect or create a network of the activities Enter the completion time for every activity listed Identify the critical path or the longest possible path to complete all activities

PRECEDENCE NETWORK ANALYSIS (PNA)With the AON method, the focus is on the activities rather than on the start and end of activities. PDA also known as Precedence Diagramming Method (PDM) uses AON method. Each unit of work in a network diagram using PDM is represented by a rectangle called the activity node. Predecessors are linked to successors by arrows, and are always upstream from successors. One work unit can be both a successor and a predecessor

PNA DEPENDANCIESDependencies describe the relationship between tasks. Finish to start (FS) This relationship is the most common. It requires the predecessor task to complete before the successor task can begin. Start to start (SS) These tasks are usually closely related in nature and should be started but not necessarily completed at the same time. Finish to finish (FF) These tasks require that the predecessor task and the successor task be completed at the same time. An example is rolling out a new software package and finishing the user training sessions.

CONT

Start to finish (SF) These rare tasks require that the predecessor doesnt begin until the successor finishes. Its often used with just-intime scheduling for inventory and manufacturing instances.

LINE OF BALANCE (LOB)

History: LOB was devised by the members of a group headed by George E. Fouch. During 1941, the Goodyear Tire & Rubber Company monitored production with LOB. It was successfully applied to the production planning and scheduling of the huge Navy mobilization program of World War ll. LOB proved to be a valuable tool for expediting production visibility during the Korean hostilities. During this period, defense suppliers used LOB.

LOB

Line Of Balance (LOB) is a management control process for collecting, measuring and presenting facts relating to time, cost and accomplishment - all measured against a specific plan. It shows the process, status, background, timing and phasing of the project activities, thus providing management with measuring tools that help:y y

Comparing actual progress with a formal objective plan. Examining only the deviations from established plans, and gauging their degree of severity with respect to the remainder of the project. Receiving timely information concerning trouble areas and indicating areas where appropriate corrective action is required. Forecasting future performance.

y

y

LOB

The line-of-balance (LOB) method of scheduling is well suited to projects that are composed of activities of a linear and repetitive nature.

Q. SCHEDULINGis quantitative scheduling, in the context that quantities to be executed at different locations of the construction project form the elements of the schedule. Q. Scheduling is Queue Scheduling in the context that trades pass through the different segments of the project in a queue sequence. It is the only scheduling technique that reveals a relation between the sequence of doing a job and the cost to be incurred.

CONT

The Q schedule is similar to the Line of Balance with some modifications, to allow for a varying volume of repetitive activities at different segments or locations of the construction project, thus the model produced is closer to reality.

CONT .

SCHEDULE COMPRESSION

This tool helps shorten the total duration of a project by decreasing the time allotted for certain activities. It's done so that you can meet time constraints, and still keep the original scope of the project. Two methods are used:Crashing y Fast-Trackingy

CONT

..

Crashing This is where you assign more resources to an activity, thus decreasing the time it takes to complete it. This is based on the assumption that the time you save will offset the added resource costs. Fast-Tracking This involves rearranging activities to allow more parallel work. This means that things that would normally do one after another are now done at the same time.

OTHER CONCEPTS OF SCHEDULING

Early Start and Early Finish Dates - This is the earliest start and finish dates possible for a task subject to predecessor task constraints and the project start date. It is found by calculating the earliest start and finish dates for a task if the task and all of its predecessor tasks were scheduled forward from the project's start date with no delays except those defined by predecessor link constraints. See also Predecessor Task.

FLOAT ( Total Float)y

The amount of time that an activity can be delayed from its early start without delaying the project finish date. Total float is a mathematical calculation and can change as the project progresses and changes are made to the project plan

SLACKTerm used in PERT for float

RESOURCE-LIMITED SCHEDULEThe resource-limited schedule is a project schedule whose schedule activities start dates, and finish dates directly reflect the availability of all resources in question. Typically, a resourcelimited schedule will not have any start dates that are early or late. Alias resource-constrained schedule

TIME-LIMITED RESOURCE SCHEDULING.

In time-limited resource scheduling, resources that are available are identified as they are, while the time is limited. If the available resources need to finish the task on time, they need to work overtime, if the task deployment is behind schedule.

UNLIMITED RESOURCE SCHEDULING.

Unlimited resource scheduling assumes that resources are available whenever and wherever the resource they are needed. Unlimited resource scheduling gives the project its earliest completion date and is the most optimistic.

RESOURCE LEVELING

Resource leveling is a way to fix resource overallocation. Resources are leveled in two ways:By delaying a task until the assigned resource has time to work on it. y By splitting a task so that part of a task is done when planned and the rest of it is done later when the assigned resource has time.y

WHY REVIEW THE SCHEDULEBecause of the uncertainty involved, the schedule is reviewed regularly, and it is often revised while the project is in progress. It continues to develop as the project moves forward, changes arise, risks come and go, and new risks are identified. The schedule essentially transforms the project from a vision to a time-based plan.

CRITICAL CHAIN PROJECT MANAGEMENT (CCPM)also referred to as Theory of Constraints. The critical chain concept was coined by Eliyahu Goldratt CCPM focuses on managing constraints, the relationship between tasks within a project and resources within project. By actively managing these key aspects it is believed that CCPM decreases project conflict and tension and provides a more balanced expectation.

CONTCCPM can result into: Project lead time reduction projects completed in less than the benchmarked performance Increased output- more projects completed in the same amount of time Improved resource productivity fewer hours required to complete projects On time delivery almost all projects completed early or on time Significant reductions in capital requirements much less work in process

CONTCCPM entails addition and subtraction of current project scheduling ways: Additions :

Planning with different task estimates y A different approach to dealing with uncertainty in planning y Focusing execution effort on buffer penetration, instead of the telephoney

Removals :Multi-tasking y Managing to task completion dates y Planning without considering resource capacityy

CCPM COMPAREDTraditional Project Management Methods1. Schedules worst-case task durations. 2. Protects individual tasks with safety time. 3. Emphasizes task progress. 4. Starts gating tasks ASAP. 5. Starts and finishes tasks at scheduled start and finish times. 6. Makes resource contention a PM "fact of life". 7. Makes multi-tasking a PM "fact of life". 8. Reacts to uncertainty by changing priorities, expediting, and creating a new schedule. 9. Makes task linkages and constraints reflect adhoc or habitual scheduling decisions.

Critical Chain Project Management (CCPM)Schedules average task durations. Protects overall project completion with buffers. Emphasizes project progress. Starts gating tasks when they need to start. Starts tasks as soon as predecessors are done, finishes tasks as quickly as possible. Resolves resource contentions explicitly. Minimizes multi-tasking by setting priorities. Manages uncertainty by monitoring impact of events on buffer consumption. Makes task linkages and constraints reflect only physical scheduling requirements.

CCPM ADVANTAGES

CCPM inherits the advantages of (Dwivedi , 2010):PMBOK: Planning and control processes. y TOC (Theory of Constraints): Remove bottleneck to resolve constraints. y Lean: Eliminate waste. y Six Sigma: Reduce Variations.y

CCPM helps to overcome the following phenomena:Parkinsons Law: Work expands to fill the available time. y Student/last minute Syndrome: People start to work in full fledge only when deadline is near. y Murphys Law: What can go wrong will go wrong. y Bad Multi Tasking: Bad multitasking can delay start of the successor tasks.y

CCPM IS BASED ON:Resource constrained situations. Optimum use of Buffer: Amount of time added to any task to prevent slippage of schedule. Project Buffers (PB): Amount of buffer time at the end of the project. Feeding Buffers (FB): Amount of buffer time at the end of a sequence of tasks. Resource Buffers (RB): It is an alert that is used to indicate that resource is needed to perform a task. This alert can be set few days before a resource is actually needed.

MICROSOFT PROJECT SOFTWAREThe application is designed to assist project managers in developing plans, assigning resources to tasks, tracking progress, managing budgets and analysing workloads. Microsoft Project creates critical path schedules. Schedules can be resource levelled. The chain is visualised in a Gantt chart. It is the most commonly used

OTHER PMS INCLUDEThere are many other PMS some webbased and include: Primavera, Basecamp, Zoho Projects, Freshbooks, Central Desktop, Podio, Smartsheet, Teamworkpm, Manymoon, Deskaway, 5Pm, Activecollab, Podio, Ace Project, Teambox, Nozbe, Feng Office, Harvest, Clarizen, Huddle, Mavenlink, Comindwork, Wrike, Goplan, Flow, Egroupware, Liquidplanner, Hyperoffice Among others

THANK YOU