Necessities begot the mother of these modern PM inventions. Navy and Booze-Allen specifically for the Polaris Missile System, addressed the uncertainty and risks with new ventures.
Interestingly, both were computer-based for network analysis; PERT using probabilistic time estimates with CPM using deterministic scheduling values. The ensuing understanding of the relationships between the activities is to me the prime importance of the critical path. The critical path method is a paradox: calculation of the longest path provides the shortest overall time in which the project can be completed. CPM continues to be a most powerful time analysis tool available to the project planner and scheduler.
Next to address are the steps to get from the plan to a working schedule. As noted, projects arise out of needs. Needs identification is the process of discovering what matters most.
This needs analysis helps the proponent organization quantify and qualify their long-term business goals and then set their short-term operational objectives.
Project g oals are the specifications of what you hope to achieve at the end of the project. The project must make sense in terms of goals that benefits people in some way. These goals specify how completing the project will make things better than they would be without the project. Project objectives consist of specific aims. Unlike goals, a project can have as many objectives as the project demands.
Project objectives require clear, concise writing so project participants understand each one. The Project Scope is, in essence, the s ize of the project. It is the sum of the products and services to be provided as a project. The Project Scope includes:. The Project Scope of Work SOW translates long-term business goals and short-term operational objectives into the functional and technical requirements chartered to the project team.
The SOW integrates the limitations and assumptions that evolve the project plan during its development. The operational objectives satisfied by the project define the tangible deliverables with the corresponding completion milestones.
This analysis yields the major phases of the project. The WBS family-tree structure is organized by either a product-orientation or a task basis. The gene-splitting genesis continues from dividing phases into activities then into tasks , with whatever necessary subcategories in between, down to the lowest WBS level—the work package Frame, As noted, the WBS window shade of the entire Project methodically opens its slats of successive levels of detail down the to task level.
If the team members are neophytes with the particular type of project, best take the WBS down to the work package level. This step requires grinding the project scope into hamburger. Creating this detailed task list from the WBS leads to the next steps. The first thing is to estimate the appropriate type and level of resources necessary to make the task happen.
Resources estimates include people-power, money both cash flows and budgets , equipment, facilities, supplies and materials, and any special technology. In estimating the duration, one needs to determine if the task is effort driven or fixed duration. For example, painting a room involves both putting the paint on the walls physical effort and waiting for the paint to dry a relatively fixed duration.
Further, it is critical to understand what type of effort drives the task— brawn or brains. Brain-based tasks are products of mental effort like estimating, programming, or designing. To sequence the work requires establishing task predecessors and successors. Though a task may have many logical relationships with other tasks, elegance requires only the elemental essence.
The tip here is to not over do it. For example, the predecessor of December 25 is December 24; and successor, December However, which years? For that matter, every day since the beginning of time is a predecessor of December 25, , and every day thereafter till Armageddon would be a successor.
Obviously, this is overkill. With the task predecessors and successor established, the network logic diagram is constructed. Creating the schedule network involves diagramming the tasks ordered by its logical relationships. With one note per task, list the pertinent information, mainly description and duration. Arrange the sticky notes in appropriate order, rearranging as necessary. Using a whiteboard as the base, diagramming of the logical relationship arrows is easily modified.
The Network Logic Diagram is the result. Next step is to perform the schedule calculations. First, we perform the Forward Pass. The first tasks no predecessors have an early start ES of Day 0. The process is now reversed, doing the Backward Pass. Commencing at the end, the final tasks no successors use the largest EF as their late finish LF day-number. The smallest LS become the LF for each preceding task.
The float or slack is the number of days a task can be delayed with out affecting the overall scheduled completion. The resultant path though the network of all of these critical tasks is the Critical Path.
Next step is to fine tune the draft schedule. By calculating the critical path, the scheduler gains essential insight as to which tasks are critical versus those tasks that can be delayed.
Anything to improve the critical path improves the entire project schedule. Likewise, focusing on noncritical tasks will likely yield less than optimal results. Another technique to improve the draft schedule is to analyze resources. Whereas, Resource Leveling starts with a given crew size then calculates the task duration based on this resources availability constraint.
Resource leveling trends to smooth out the erratic swings in allocation requirements. Another resource refinement technique is crashing tasks on the critical path.
This involves adding more resources to shrink the critical task duration. Crashing should only be done on tasks on the critical path and then on those tasks that nets the most cost-effective result Frame, We humans can think in three-space but then act in a step-by-step fashion. Though completing one task before tackling another is preferred, how can any thing be done on time? Mothers the true renaissance PM and movie producers make things happen by attacking multiple tasks simultaneously versus sequentially.
Fast tracking is a broader form of this concurrent scheduling technique, commonly used in construction. Successive phases are started as soon as possible. For instance, the site work and foundations of the construction phase is started as soon as sufficient design packages are ready. The facility design and procurement phases continue in concurrence with the construction phase.
Though not fool proof—this fast-tracking method gives rise to many change orders fixing the design mistakes found in the field.
The compiled NLD can look like a spider web—a gossamer tapestry of order and logic. Correspondingly, the network can be an incomprehensible rat's nest of derisive drudgery and tedious toil. De-bottlenecking the choke points is one way to improve on this situation. By visual inspection, the NLD reveals tasks and the paths through which too much logical connections flow.
By astute rerouting of the process paths and shrewd re-piping of the network logic, the over-pressured task points can be stressed relieved. The schedule is more that just a road map, giving the direction to the project team. The schedule is an itinerary of the planned activities combining the scope requirements with the work packages. The schedule is both mile marker and a benchmark measure. Lastly, the project schedule provides the framework for gathering and sorting out all of the paraphernalia and souvenirs of the trip, both file folder and trip photo album.
The captain's ship log and the team's diary of the project journey. It is time to way anchor and trim the sails. In starting a project, the schedule provides a focus and structure for the new teammates, probably recently assembled. Though people feel most comfortable with a democratic form of governance where their words are heard and considered, the benevolent dictatorship format is the most efficient.
The project schedule provides the visual balance between these two opposing forms for team structure. Though the quality of the team is the prime determiner of project success, it is the synergy of the collective efforts more than the sum of individual talents that make a project click.
It is typical for the project plan and schedule to be developed by others than those of the team involved with the execution. The project implementation kick-off necessitates the execution team to collectively experience the project plan for the first time.
Their buy-in to the approved schedule is the essential step of the project initiation, with out which the project plan implementation is doomed.
Athletic contests can provide immediate feedback as to progress and performance. The scoreboard shows clearly which team is ahead. The mountain of meaningless statistics placates the also-rans in second place, keeping the announcers jabbering away while the activity on the field continues.
The game plan may now be in the can, but the game rolls on. Likewise, the winning team may be ahead in spite of their best efforts to fail, working hard to grasp sudden defeat from the jaws of victory easily within their grasp.
As a long time, beleaguered fan of the Detroit Lions, the writer knows well from experience. The project schedule provides the baseline against which all activity is measured and evaluated. The team tracks activity progress. This progress data then requires their honest assessment and frank analysis to determine and measure overall project performance.
The project team uses the project schedules planned—versus—actual performance to assess themselves. They become their own harshest critics in communicating the project status to the project stakeholders. Brevity is the spice of life, and humor is life's spiciness. The best comedians tell jokes with a quick punch line. They want to leave their audience grinning and amused but not rolling in hysterics.
The Bob Hope versus the Milton Beryl school of vaudeville comedy. Are project managers really the new millennium's stand up comedians? Well, finding humor in the face of shear adversity in the project-from-hell is not a bad trait for a project leader. Project leaders are required to play the action character on a regular basis. At each reporting period, the PM must:. Quite a tall order for mere mortals; however, project leaders are not allowed to feign mortality.
Making things happen is a project leaders key trait. This requires communicating the project news, both good and bad, and then correcting the bad stuff while continuing the good. A project manager should spend most of their time planning with their team, guiding them in the proper direction.
Fighting fires are for firemen. Consider a project that has been planned in detail, including a time-phased spend plan for all elements of work. Figure 1 shows the cumulative budget cost for this project as a function of time the blue line, labeled PV. It also shows the cumulative actual cost of the project red line through week 8.
To those unfamiliar with EVM Earned Value Performance Management , it might appear that this project was over budget through week 4 and then under budget from week 6 through week 8.
However, what is missing from this chart is any understanding of how much work has been accomplished during the project. If the project was actually completed at week 8, then the project would actually be well under budget and well ahead of schedule.
At the end of each week, the project manager identifies every detailed element of work that has been completed, and sums the EV for each of these completed elements. Earned value may be accumulated monthly, weekly, or as progress is made.
The best way to read these three-line charts is to identify the EV curve first, then compare it to PV for schedule performance and AC for cost performance. It can be seen from this illustration that a true understanding of cost performance and schedule performance relies first on measuring technical performance objectively. If these components for the schedule are not available, they can be created with a consensus-driven estimation method like Wideband Delphi forecasting tool.
The reason for this is that a schedule itself is an estimate: each date in the schedule is estimated, and if those dates do not have the buy-in of the people who are going to do the work, the schedule will be inaccurate. The WBS is a hierarchical reflection of all the work in the project in terms of deliverables.
In order to produce these deliverables, work must be performed. A work breakdown structure WBS , in project management and systems engineering, is a deliverable-oriented decomposition of a project into smaller components. A typical approach in developing a WBS is to start at the highest level, with the product of the project. For example, you are assigned as the project manager of a New Product Development project. The new product you are developing is a new toy for children age's five trough nine.
The objective of this product development project is to increase the revenue of the organization by ten percent. Each level of the WBS is a level of detail created by decomposition.
Decomposition is the process of breaking down the work into smaller, more manageable components. The elements at the lowest level of the WBS are called tasks. In the example above, brochures, advertising and commercials are all work packages or tasks. In Project Insight, project management software, control accounts are called 'summary tasks. The decomposition of a schedule will continue at varying rates. As a project manager, the level of decomposition will be dependent on the extent to which you will need to manage.
Project Insight supports as many levels of hierarchy as are needed. The expectation is that each task will have a single owner and the owner is expected to manage and report on the work necessary to deliver the task. In Project Insight, this is called the 'task owner.
In some cases, these activities are the physical deliverables, but in other cases they are the actions that need to be performed. A physical deliverable, for example, might be an image an actual file that is needed for the brochure. During project scheduling, the first step is to define the work. This is typically done in a hierarchical arrangement called a work breakdown structure WBS although the simplest projects may use a simple list of tasks.
In either case, it is important that the WBS or list be comprehensive. It is also important that the elements be mutually exclusive, so that work is easily categorized in one and only one element of work. The most detailed elements of a WBS hierarchy or the items in a list are called activities or tasks. The second step during project scheduling is to assign a value, called planned value PV , to each activity.
For large projects, PV is almost always an allocation of the total project budget, and may be in units of currency e. Assigning weighted values and achieving consensus on all PV quantities yields an important benefit of EVM Earned Value Performance Management , because it exposes misunderstandings and miscommunications about the scope of the project, and resolving these differences should always occur as early as possible. Some terminal elements cannot be known planned in great detail in advance, and that is expected, because they can be further refined at a later time.
These simple earning rules work well for small or simple projects because generally each activity tends to be fairly short in duration. The final step is to execute the project according to the plan and measure progress.
When activities are started or finished, EV is accumulated according to the earning rule. This is typically done at regular intervals e. In fact, waiting to update EV only once per month simply because that is when cost data are available only detracts from a primary benefit of using EVM Earned Value Performance Management , which is to create a technical performance scoreboard for the project team.
Construction management decisions are made based on schedules that are developed during the early planning stage of projects, yet many possible scenarios should be considered during construction. These decisions, however, need to be supported by a risk management plan. In many cases, even though allowances are considered during the planning stage to minimize the risks, they may not be sufficient to cover all possibilities and the planner will still have to react when changes occur.
For instance, suppose that at a pavement facility, the raw materials that are coming from a particular quarry are unexpectedly insufficient, or that abnormal weather makes it too difficult to perform tasks outdoors. These, and many other unpredictable events, constantly affect project schedules. In many cases, DMs are required to make decisions quickly during construction. Even though there are important resources whose restricted availability could affect project schedules such as equipment, labor, or subcontractors, this article mainly discusses how fuzzy mathematical models may be used to generate construction project schedules and how to incorporate restrictions that are defined by schedulers on items such as materials, time, and cost.
Time cost tradeoffs may also be incorporated into schedules using fuzzy mathematical models, which facilitate time-cost trade-off analysis. In this study, linear relations are assumed in fuzzy mathematical models. The proposed approach can help planners and schedulers allocate available resources to competing tasks in such a fashion that two conflicting objectives can be satisfied using fuzzy math modeling.
The practitioners usually have little time to react to changes and the proposed approach can provide fast solutions for small to moderate size problems up to a couple of thousand activities, depending on the computer used. Besides material shortages and hence delays in project completion times, some other variables also affect construction projects such as activity durations, early start time, late start time, early completion time, late completion time, normal costs, and crash costs.
The weather, traffic, and the limited avail- ability of other resources such as skilled workers, machines, equipment, etc.
Therefore, float calculated using CPM techniques will lose its significance and new critical sequences will develop. Commercial project management software packages based on CPM schedules integrated with compatible software provide DMs with valuable alternatives to prevent, or minimize, the effects of probable delays, such as the software used for the Delay Analysis System.
A different approach has been followed by other writers, who stress that considering project constraints is not adequate because constraints need to be analyzed and prioritized depending on their repercussions on the entire project. CPM techniques with discrete information instead of continuous membership functions have proven to be more efficient and they provide not optimal, but usable solutions. However, some optimization techniques present the opportunity for analyzing more than one objective at a time and this permits a more realistic approach.
Uncertainties have been analyzed by using fuzzy goal programming and optimal solutions have been achieved while simultaneously considering two objectives and using membership functions. Therefore, having similar characteristics such as the plans and project duration, and using the same equipment, standard conditions, and resources for two projects does not imply the application of the same procedures nor guarantee similar results.
Conditions could change and there could be delays and unexpected situations that arise during construction. The volatility in the construction materials market makes scheduled material deliveries uncertain.
For example, as the demand for steel or cement increases, deliveries could be delayed and projects may have to be cancelled. DMs may use their experience to help achieve goals or objectives as effectively as possible by re-planning and rescheduling projects when it becomes necessary to do so. The efficiency of a construction project depends on many variables e. Personnel in the construction industry frequently have to address material management issues, such as materials not being available where and when they are needed, and a lack of information about where materials are located at job sites.
These problems may increase expenses and the required time to complete a project. Using fuzzy mathematical models allows project managers to try to achieve the two main project objectives of minimizing costs and time under material restrictions, and it helps them consider ambiguities in decisions by using membership functions. However in practice most contractors do not control and update schedule frequently due to lack of proper controlling method in the real construction world.
The main objective of providing strategies for scheduling is to provide engineers with corresponding strategies rather than the fast track crashing project. Schedule control strategies mainly are to prevent the condition that parts of critical activities are behind schedule severely and extra resource for crashing the project will be paid.
Though the techniques of scheduling are well developed, they are inconsistently applied throughout industry. There is not a much better conclusion to be made than that of project managers being the project success determinants through their tracking of project schedules, resources, budgets and project related assets in real time.
The project schedule can be viewed and updated by team members associated with the project, keeping everyone well informed on the overall project status. To compress the project time, project managers have to accelerate some activities at an additional expense during project scheduling. Different decisions will be taken regarding time and cost of each activity for overall network, the set of decisions that result will contribute to desirable time, cost and realization of time cost trade off problem.
Shahsavari Pour, M. Modarres, R. Moghaddam and E. Prabuddha De, E. Dunne, J. Ghosh and C. Kolisch and R. Senouci and K. Bokor, T. Kocsis and G. Karaca, Z. Moder, J. Peter W. Planning and Scheduling 8.
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