Research On The Technology Of Schedule Management Of The Networked Collaborative Manufacturing Project

The globalization of manufacturing and the network-based manufacturing havechanged the traditional centralized manufacturing organization mode intoproject-driven and distributed network-collaborative manufacturing organizationmode which is based on modern information technology, especially networktechnologies. To manage the schedule of networked collaborative manufacturingproject (NCMP) effectively, this dissertation takes the collaborative manufacturingproject of the key components of a certain type rocket engine as a typical example,and goes deep into researching on the theories, technologies and methods of the keyproblems related to schedule management, including the task duration estimating,the project plan, the schedule tracking and controlling and the task dynamicscheduling. Combining with a practical project, a network-collaborativemanufacturing project schedule management prototype system is built to support theopinions and research results in this paper.The main research work and opinions are as follows:(1) After classifying the mode of the network-based manufacturingorganization and analyzing their characteristics, the paper makes a definition ofNCMP for the collaborative manufacturing of complex product and limits itsorganization mode to the virtual enterprise (VE). Adopting the notion of domain inDistributed Artificial Intelligence, this dissertation divides the enterprises into twological domains, the Global Domain and the Enterprise Domains, on their position inVE. By analyzing the business process of NCMP, especially the business process ofschedule management in NCMP performing phases, the dissertation divides thebusiness process of NCMP into three logic levels: the global business process, theshared business process and the private business process. Based on the researchmentioned above, a multi-agent workflow model of NCMP is put forward to supportthe schedule management of NCMP.(2) It is difficult to resolve the problem of task duration estimate under thecondition of NCMP because of a shortage of history data, what's more, the taskduration is subject to effect of uncertain factors. However, all of the existingstochastic data estimating methods can not resolve the problem of little basic datacommendably, so a new task duration estimating method based on Grey SystemTheory is put forward, and the estimating process of the model is discussed in detailin this dissertation, which includes the selection of data using a gray filter modelbefore estimating, the task duration estimated process by GM(1,1) and the taskduration amend when risk is taken into account. Finally the opinion is validated by a case.(3) Based on the characteristics of NCMP schedule schema and the domainpartition result of VE, a multi-levels and multi-phases schedule schema model ofNCMP is proposed. The method of calculating the max executing time window ofthe task with uncertain task durations, the algorithm of the project schedulepreliminary scheme in global domain, the self-leaming negotiation algorithm basedon Bayesian theory between sponsor and its friends, and the optimal algorithm ofdetail production plan based on Theory of Constraint (TOC) in enterprise domainsare researched in the paper.(4) Progress tracking is important to NCMP because its business is distributedin different enterprises. Based on the advantages of project management andworkflow technologies in process management, the dissertation suggests an idea thatintegrates them to tracking the schedule of NCMP by the information sharingbetween the process model (PML) of workflow and the PERT model (PERTML) ofPM, so the information structure and the mapping mechanism of PML and PERTMLare studied deeply, and the information mapping is achieved by XML. Further more,combining with the advantages of Web Services in information integrating of crossorganizations, a process model of task schedule data collection based on WebServices and workflow of NCMP is put forward, and the data collection process isdescribed in detail.(5) In order to control the schedule of NCMP effectively, the dissertationproposes a multi-levels and multi-phases schedule controlling model, then gives anapproach to identify progress bias degree with practical progress vanguard line and amethod to judge whether the bias identified influence subsequent task and wholeproject plan. Based on the analysis of progress status and scheduling means of thetask, the dissertation put more attention to studying the gray line plan algorithm ofshortening the duration of key tasks under the condition of logic relation unchangedbetween tasks, and the negotiation algorithm of overlapping the duration of theconterminous key tasks under the condition of task duration fixed.(6) This dissertation makes use of the theories and methods mentioned aboveon a case named as the distributed collaborative manufacturing project of the keycomponent of a certain type rocket engine, and a light network-collaborativemanufacturing project schedule management prototype system based on multi-agentand Web Services is developed.