《工程项目计划系统PPT课件》由会员分享，可在线阅读，更多相关《工程项目计划系统PPT课件（101页珍藏版）》请在金锄头文库上搜索。
1、.,1,工程项目计划系统PROJECT PLANNING,.,2,在总目标确定后，分析总目标能否实现 计划同时又是目标的分解过程 计划是实施的指南和实施控制的依据 业主和项目的其他方面需要利用计划的信息,一、计划的作用,.,3,One distinguishing feature of projects is that each is tailored toward some unique end-item or result. That uniqueness implies that every project must be defined anew and a scheme create
2、d telling everyone involved what to do.,.,4,Three things occur in the planning and control process: (1) During the conception and definition phases a plan is prepared specifying the project requirements, work tasks, responsibilities, schedules, and budgets; (2) during the execution phase the plan is
3、 compared to actual project performance, time, and cost; if there are discrepancies, (3) corrective actions are taken and the requirements, schedules, and budgets updated.,.,5,Planning steps For starters, the project team needs to answer questions about what has to be done, how it has to be done, by
4、 whom, in what order, for how much, and by when. The formalized way to answer these questions is through the planning process.,.,6,Project objectives, requirements, and scope are set; The specific work activities, tasks, or jobs to achieve objectives are broken down, defined, and listed; A project o
5、rganization is created specifying the departments, subcontractors, and managers responsible for work activities,.,7,A schedule is prepared showing the timing of work activities, deadlines, and milestones; A budget and resource plan is prepared showing the amount and timing of resources and expenditu
6、res for work activities and related items; A forecast is prepared for time, cost, and performance projections for the completion of the project.,.,8,Tools of Project Planning Work breakdown structure and work packagesused to define the project work and break it down into specific tasks. Responsibili
7、ty matrixused to define project organization, key individuals, and their responsibilities. Events and milestonesused to identify critical points and major occurrences on the project schedule.,.,9,Gantt Chartsused to display the project master schedule and detailed task schedules. Networksclearly sho
8、w interdependencies among activities. Critical path analysiscritical path gives the expected project duration. PERT/CPMprogram evaluation however, others can fall behind without delaying the project.,.,22,网络计划技术 是一种以网状图形表示计划或工程开展顺序的工作流程图。分单代号和双代号两种。,.,23,.,24,The two common methods for constructing
9、network diagrams are called activity-on-node (AON) and activity-on-arrow (AOA). Both were developed independently during the late 1950sAON as part of the CPM planning method, and AOA in the PERT method.,.,25,Activity-on-arrow diagrams In the AOA method, the activity is represented as a directed line
10、 segment (called an arrow or arc) between two nodes (or circles). The nodes represent the start and finish events for the activity in between them. (The numbers inside the nodes have no significance here. In general, however, they are used to identify each event. The numbers do not need to be in any
11、 particular sequence, but every event must have a unique number.),.,26,.,27,predecessor, immediate predecessor,successor, immediate successor,sequential activities, parallel activities,dummy activities,.,28,An AOA network is constructed by first drawing a node to represent the origin event; this rep
12、resents the start of the first activity in the project. The final or terminal node in the network represents the project completion. Every network should have only one origin event and one terminal event. All arrows must progress toward the right-end of the network and there can be no doubling back
13、or loops.,.,29,Dummy activities A dummy activity is used to illustrate precedence relationships in AOA networks. It serves as a “connector”, however, and represents neither work nor time. In practice, dummy activities should be used sparingly to keep the network as simple as possible.,.,30,In constr
14、ucting networks by hand, as a rule it is easiest to start by putting in dummy activities wherever they seem necessary, then removing them from places where they are not necessary. The “overriding rule” is that dummies cannot be removed whenever it results in two or more activities that run between t
15、he same two start and finish nodes.,.,31,Redundant activities All activities in a project except the first one have predecessors. Although only the immediate predecessors need be known to construct a network, it is easy to accidentally specify more predecessors than necessary.,.,32,.,33,The critical
16、 path The major use of networks is for schedulingdetermining how long the project will take (the expected project duration) and when each activity should be scheduled.,.,34,The expected project duration, Te, is determined by finding the longest path through the network. A “path” is any route comprised of one or more arrows (activities) connected in sequence. The longest path from the origin node to the terminal node is called the critical path; this gives the expected project duration.,.,35,Mult
