Define activities
Regardless of the size of the project, a project consists of multiple "activities", and only by accurately identifying and defining each activity can it provide a basis for estimating activity resources and developing a schedule.
defining an activity process is about identifying and documenting all the activities that need to be taken to complete a project deliverable. break down work packages into activities that serve as the basis for estimating, scheduling, executing, monitoring, and controlling project work.
ACTIVITIES: THE WORK REQUIRED TO BE DONE IN ORDER TO COMPLETE THE WORK PACKAGE (A FURTHER BREAKDOWN OF THE WORK PACKAGE IN THE WBS) IS THE MOST BASIC UNIT OF WORK THAT IS SCHEDULED WHEN IMPLEMENTING THE PROJECT. ACTIVITIES AND WORK PACKAGES ARE 1-ON-1 OR MANY-ON-1 RELATIONSHIPS.
1. DETAILED EXPLANATION OF THE ITO THAT DEFINES THE ACTIVITY:
(1) rolling planning: rolling planning is an iterative planning technique, that is, detailed planning of the work to be completed in the near future, while roughly planning the long-term work at a higher level. the level of detail of the work breakdown varies at different stages of the project life cycle.
(2) list of activities: the list of activities is a comprehensive list of all activities required by the project. the milestone list lists all the milestones of the project.
(3) activity attributes: including activity code, activity description, immediately before activity, tightly followed activity, logical relationship, advance amount, lag amount, resource demand, mandatory date, constraints, assumptions.
(4) milestone list: a list of key events in the project. milestones are important time points or events in a project that are mandatory and selective, and the most prominent feature of a good milestone is that there is no ambiguity in reaching the criteria of this milestone. brainstorming is common when determining milestones.
after the definition of the project activity is completed,
Sort the order of activities
the sequential description of project activities is generally described graphically, which is more intuitive. in practice, project management software is usually used, and manual or automated tools are used to complete the work.
the order of activities is the process of identifying and documenting relationships between project activities. define a logical sequence of work to achieve maximum efficiency under all established project constraints.
1. ITO DETAILS OF THE ORDER OF ACTIVITIES:
(1) tight-front relationship mapping method: also known as the leading diagram method, used to compile a network map of project progress, as detailed below.
(2) determination of dependencies: since the dependencies between activities may be mandatory or selective, it is necessary to determine the dependencies between activities, as detailed below.
(3) advance quantity and lag amount: refers to the addition of time advance quantity and lag amount between activities, which is used to more accurately express the logical relationship between activities, as described below.
(4) project progress network diagram: the graph of each activity in accordance with the order and dependencies of each activity, including the leading map method, the arrow line diagram method, etc., as detailed below.
2. four relationships to determine the dependencies between activities:
(1) mandatory dependency: required by legal contracts; determined by intrinsic nature; related to objective limitations
(2) selective dependencies: first logical relationship, priority logical relationship, mostly in accordance with the order of recognized best practices
(3) external dependencies: the relationship between project activities and non-project activities, external dependencies are not within the scope of team control
(4) internal dependencies: the relationship between project activities and activities, usually within the control of the project team
3. the leading diagram method (pdm), also known as the tight front relationship drawing method, is a method used to compile the network diagram of the project progress. with squares representing activities and arrows representing logical relationships, this diagram is also known as a single-code network diagram (only nodes need to be numbered). the leading graph method includes 4 dependencies between activities:
(1) END-START (F-S): AFTER THE PRE-SEQUENCE ACTIVITY ENDS, THE FOLLOW-UP ACTIVITY CAN START
(2) END-END (F-F): AFTER THE END OF THE PRE-SEQUENCE ACTIVITY, THE FOLLOW-UP ACTIVITY CAN BE COMPLETED
(3) START-START (S-S): AFTER THE PRE-SEQUENCE ACTIVITY BEGINS, THE FOLLOW-UP ACTIVITY CAN START
(4) START-END (S-F): AFTER THE PRE-SEQUENCE ACTIVITY BEGINS, THE FOLLOW-UP ACTIVITY CAN END
4. in the leading diagram method, each activity has the following times:
(1) EARLIEST START TIME (ES)
(2) EARLIEST COMPLETION TIME (EF): = ES + DURATION
(3) LATEST COMPLETION TIME (LF)
(4) LATEST START TIME (LS): = LF - DURATION
5, the arrow line diagram method (adm) is a network diagram drawing method that uses the arrow line to represent the activity, the node represents the event, this diagram is called the double code network diagram (activities and events need to be numbered), the start of the activity (arrow tail) event is called the activity of the immediate event, the end of the activity (arrow) event is called the activity of the tight event. in the arrow line diagram method, there are three principles (often used in cases or judgments):
(1) each activity and event in the network diagram must have a unique code name
(2) at least one of the preceding and post-event codes of any two activities is different, and the node codes are getting larger and larger along the arrow direction
(3) activities that flow into (out) the same node, and have common tight back activities (or tight front activities)
virtual activities are represented by virtual arrows and do not consume time or resources, but are only meant to express activity dependencies
6. adding the amount of time advance and lag between activities can more accurately express the logical relationship between activities.
ADVANCE AMOUNT: THE AMOUNT OF TIME THAT THE TIGHT ACTIVITY CAN BE ADVANCED RELATIVE TO THE TIGHT FRONT ACTIVITY. EXPRESSED AS A NEGATIVE NUMBER: EXAMPLE SS-10
LAG: THE AMOUNT OF TIME THAT THE TIGHT ACTIVITY CAN BE POSTPONED RELATIVE TO THE TIGHT FRONT ACTIVITY. EXPRESSED AS A POSITIVE NUMBER: EXAMPLE FS+15
in addition to the first and last two activities, each activity and each milestone has at least one front activity and one back activity. project teams can logically sequence activities to create a solid project schedule. using advance or lag between activities makes project scheduling more practical.
Estimating activity resources
The process of estimating activity resources is closely related to the process of estimating costs, so it is generally necessary to put the two processes together.
estimating activity resources is the process of estimating the type and quantity of materials, personnel, equipment and supplies required to carry out activities in order to make more accurate cost and duration estimates.
ITO DETAILS FOR ESTIMATING ACTIVITY RESOURCES:
(1) resource calendar: a resource calendar is a calendar that indicates the available work days or shifts for each specific resource (when and for how long).
(2) estimated data published: estimated reference data published by official or authoritative institutions.
(3) bottom-up estimation: estimate and summarize from bottom to top according to the decomposition structure.
(4) activity resource requirements: the type and quantity of resources required for each activity in the work package are clarified.
(5) resource decomposition structure (rbs): it is a hierarchical display of resources by type and category, which helps to organize and report the progress of the project in combination with the use of resources. for example:
since the focus of this article is on project progress management, further estimation of the duration of the activity is required after the estimation of the resources for the activity, as described below.
Estimate activity duration
estimating activity duration is the process of estimating data on the required work periods for each activity based on the results of resource estimates, and its role is to determine the amount of time required to complete each activity, providing the main input to the progress planning process.
1. ITO FOR ESTIMATING THE DURATION OF THE ACTIVITY:
(1) analogy estimation: estimate based on data from historical projects.
(2) parameter estimation: estimate based on historical data and parameter model.
(3) three-point estimation: estimation based on three situations: optimistic, likely and pessimistic.
(4) reserve analysis: it is a time reserve carried out to take into account uncertainties in the estimation.
(5) activity duration estimate: the result of a single activity duration estimate based on the above estimation method.
(1) input: schedule management plan, activity list, activity attributes, activity resource requirements, resource calendar, project scope description, risk register, resource decomposition structure, business environment factors, organizational process assets
(2) tools and techniques: expert judgment, analogy estimation, parameter estimation, three-point estimation, group decision-making techniques, reserve analysis
(3) output: activity duration estimate, project file update
2. software development projects usually use loc to measure the scale of the project, loc refers to the number of all executable source code lines, including the number of executable source code lines, including data definitions, format declarations, etc.
single line code value = effort (person-month) * monthly cost per person / total number of code lines
3. summary of methods for workload and duration estimation:
(1) The Expert Assessment Method (Delphi) applies to situations where historical data are not available;
(2) the analogy estimation method is applicable to the situation that there are similar historical projects, and the accuracy of the estimation results depends on the integrity and accuracy of the historical project data;
**equivalent lines of reusable code = [(redesign percentage + recode percentage + retest percentage)/3] * lines of code are already available.
(3) the parameter estimation method is suitable for the case of historical data and parameters, and the accuracy of the estimation depends on the maturity of the parameter model and the reliability of the basic data
(4) reserve analysis, called time reserve or buffer time, is incorporated into the project schedule to cope with uncertainty in progress.
1) emergency reserves. included in the schedule benchmark to address identified risks, associated with "known-unknown" (knowing that the risk exists but cannot be predicted).
2) manage reserves. not included in the schedule, but part of the total duration of the project, is a project period specifically set aside for administrative control to deal with unforeseen work within the scope of the project. associated with "unknown-unknown" (not known and unpredictable) risks.
(5) THREE-POINT ESTIMATION, ALSO KNOWN AS PLAN REVIEW TECHNIQUE (PERT), ESTIMATES THE COMPLETION TIME OF PROJECT ACTIVITIES ACCORDING TO THREE SITUATIONS:
1) Optimistic time (QT), denoted by a when calculating
2) The most likely time (MT), denoted by m when calculating
3) Pessimistic time (PT), denoted by b when calculating
the expected time t (mean) calculation formula for an activity:
the formula for calculating the variance for the duration of an activity:standard deviation:
4. an activity
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