基于关键链的项目进度管理方法研究

关键链项目管理方法是约束理论在项目管理中的应用。在对关键链项目管理方法的基本思想和理论基础分析介绍的基础上,针对如何利用关键链将项目计划与项目进度控制更好的结合进行了研究和评价;利用项目管理领域相关知识,补充了缓冲区管理的方法和实施步骤,并运用实例进行了求证。     

用混合蚁群算法求解多工序订单生产计划

多工序订单生产排序问题,是一类典型的组合优化问题。采用混合蚁群算法,对一种多工序订单模型进行建模求解,并给出了详细的算法步骤。通过用不同数量的订单、工序组合的数据进行模拟计算与结果比较,证明了混合蚁群算法在求解此类的问题的有效性以及良好的鲁棒性。     

The M/G/∞ Queueing Model for Optimistic Concurrency Control

The M / G /∞ queue with Optimistic Concurrency Control (OCC) is a model for a special form of parallel transaction processing in a real-time database. Transactions arrive according to a Poisson process and require some generally distributed execution time. One of the differences with ordinary multi- and infinite-server queueing models is that under OCC the successful completion of one transaction may immediately cause the failure of one or more of the other transactions. This happens if the completing transaction has overwritten a data-item that is in use by another transaction in progress. As soon as this failure is detected the failed transaction is restarted. So the total service time of a transaction consists of its final successful run and the time spent on unsuccessful runs.
In this study we develop an approximation for the distribution of the total service time, and test the approximation against simulation. Although in practice the number of servers is never unlimited, this study provides valuable insight in the asymptotics with respect to the number of servers. The approximation clearly demonstrates the very limited performance gain from an increase of the number of servers.     

Generating of multi-criteria alternatives for decision-making in electric light rail control

The purpose of this paper is to study and evaluate genetic algorithms and scheduling theory about the methods of controlling public electric transport. Scheduling theory can be defined as criteria of time constraints for target functions of the optimal electric transport control task and for electrical process diagnostics task. Mathematical models and procedures are developed for the control of electrical processes and the optimization of railway traffic control, using scheduling theory and multi-criteria of decision making. Functional dependencies between electrical processes and dynamics of electric transport flow states are investigated in the research. Genetic algorithms are investigated for getting dynamic multi-criteria optimization of processes in real time mode. Efficiency of proposed methods about procedures for optimal electric transport flow control is analyzed and. Safety is considered as an inherent component of the total transport system, which embraces infrastructures, goods and containers, transport users and operators, vehicles and vessels, measures at policy and legislative levels includes decision support and validation tools. Integrated safety and security systems for surface transport systems includes advanced modeling, simulation and engineering tools, aiming at the improvement of safety and security performance of transport systems. Development will include methodologies and designing environments for risk based design and approval, roll-over test development and pre-normative research towards regulations based on virtual testing methods as well as mechatronic systems for dynamic stability, reliable and effective braking systems for vehicles. The paper is based on authors＇ previous scientific work which researches the intelligent device systems and their applications in transport systems. Intelligent devices are controllers, which have interface to work in global network and wireless networks, and are programmed to use methods of the artificial intelligence. Intelligent devices have possibilities to negotiate with each other and to coordinate their work to get better decision. The results of experiments show the possibility of the developed systems to prevent accidents and to avoid different problems by intelligent diagnostic and coordination devices.     

一种基于LTE业务特征的调度算法切换系统

针对LTE业务QoS特征多样化且应考虑业务付费等级的问题,提出了一种改进的比例公平 调度算法。新算法引入不同业务的各QoS指标、付费等级作为参数,并根据各业务的具体QoS 需求在各参数的不同加权配置下切换。仿真结果表明,新算法不但可以极大提高付费业务 的各项QoS指标,还能让所有业务的QoS指标达到既定需求,更好地适应了LTE网络规划的要 求。     

生产企业合同交货期确定及合同排序

讨论了企业订货合同管理中面临的决策问题以及解决途径。应用机器工件调度理论求解包括提前和延期惩罚的合同排序问题，给出了启发式排序规则和求解搜索策略。采用了3种启发式方法：1）接排序规则排序；2）对初始排序施加成对交换技术改善；3）射束搜索技术。实验结果表明，第3种求解质量具有明显优势，能得到令人满意的结果。     

Decentralized negotiation: An approach to the distributed planning problem

DENEGOT is a distributed planning framework that bases conflict resolution on decentralized peer negotiation. Negotiation is viewed as a distributed search through potential compromises. The framework assumes that a satisficing solution is acceptable (a reasonable assumption in many complex domains). To estimate the quality of potential solutions, the negotiation search space is structured into a lattice of sets of potential compromise solutions based on hard constraints. A solution in a higher set in the lattice, if it is achievable, will be preferable over a solution in a lower set. Agents first search under the hard constraint level representing the highest quality solution standard achievable in the current situation. By relaxing hard constraints, the set of compromises that qualify as a solution are enlarged. Agents search for a resolution under the relaxed hard constraint set when a solution cannot be found under the current set of constraints. The framework consists of three iterative problem-solving phases: coordinated search, negotiation state analysis, and constraint relaxation. The application of the DENEGOT framework to distributed planning problems in two domains is demonstrated.This work was partly supported by the Defense Advanced Research Projects Agency (DARPA), monitored by the Office of Naval Research under contract N00014-89-J-1877, by the Office of Naval Research under a University Research Initiative grant, number N00014-86-K-0764, and by the PRC Independent Research and Development project, number R00911. DPS.     

Policy-sensitive selection and phasing of road investments with a goal program

A goal program to select and schedule road projects can include policy considerations in addition to those covered by cost-benefit evaluation. Five economic benefits and twelve environmental, developmental and accessibility objectives constitute the goals in a rural application in Western Australia. A plan and construction schedule can be generated for any set of priorities, each satisfying the budget constraint. Government can choose from them to match current policy concerns and meet the needs of affected residents. The method is particularly valuable when there are linkages between projects.     

基于实时信息的铸造企业质量监控系统关键技术

铸造生产是由多工序组成的连续生产过程,为了有效地满足用户对产品质量要求,实现企业提质降耗的目标,必须对所有工序进行综合控制.以黄石某铸造有限公司计算机集成质量控制工程为背景,分析了该企业拥有的DISA造型生产线计算机集成质量控制系统的逻辑结构、物理结构,以及各分系统质量计划系统、质量数据采集系统、质量评价与控制系统、质量信息综合管理系统的功能特点及相互关系,对铸造企业计算机集成质量控制系统进行了规划与设计,提出了基于计算机网络和分布式数据库管理系统和对整个企业的生产质量进行综合控制的计算机辅助质量控制系统.对DISA造型生产线生产的各工序的质量进行综合控制,达到以最低成本制造出符合用户要求的优质产品并保证如期交货的效果.     

新旧动能转换下山西农业与现代服务业耦合发展的路径选择

山西农业与现代服务业具有相互影响和相互促进作用.在新旧动能转换背景下,对山西省2014—2018年农业和现代服务业发展的主要指标在运用层次分析法和熵值法综合确立权重的基础上,进一步通过耦合协调度模型对二者进行实证分析.结果表明山西农业与现代服务业的发展处于轻度失调状态.深化标准化服务体、创新科技服务、开发信息服务、推进品牌服务、强化职业教育服务和创新金融服务将有助于提升山西农业和现代服务业的耦合发展质量.