基于概念的教育资源元素材聚类方法研究

针对教育资源元素材种类多、独立性强等特点，研究了概念聚类方法解决领域知识的分类和归并问题，并实现了概念的动态聚类算法和归并算法，分析了该算法的效率和聚类准确性．     

路政应急管理中资源布局的混合整数规划模型

本文根据道路灾害事故的发生特点,对城市路桥养护系统的运行模式和资源的合理调用机理进行分析,考虑到事发地点潜在的资源需求概率,建立资源布局的混合整数规划模型.本模型中资源布局方案的调度决策基础是在灾害事故的资源需求不发生变化的条件下,使得每个救助点的资源同时部分地为辖区内现有事故和潜在事故服务,而现有事故的剩余需求由其他救助点派出资源来满足.该模型的目标是解决城市中因同一时间段内发生两起灾害事故而造成路桥破坏导致的救助资源短缺问题,同时避免资源的闲置浪费.最后,通过算例证明,本方法较通常方法对城市总的资源配置量大大减少.     

Discovery Through Gossip

We study randomized gossip‐based processes in dynamic networks that are motivated by information discovery in large‐scale distributed networks such as peer‐to‐peer and social networks. A well‐studied problem in peer‐to‐peer networks is resource discovery, where the goal for nodes (hosts with IP addresses) is to discover the IP addresses of all other hosts. Also, some of the recent work on self‐stabilization algorithms for P2P/overlay networks proceed via discovery of the complete network. In social networks, nodes (people) discover new nodes through exchanging contacts with their neighbors (friends). In both cases the discovery of new nodes changes the underlying network — new edges are added to the network — and the process continues in the changed network. Rigorously analyzing such dynamic (stochastic) processes in a continuously changing topology remains a challenging problem with obvious applications. This paper studies and analyzes two natural gossip‐based discovery processes. In the push discovery or triangulation process, each node repeatedly chooses two random neighbors and connects them (i.e., “pushes” their mutual information to each other). In the pull discovery process or the two‐hop walk, each node repeatedly requests or “pulls” a random contact from a random neighbor and connects itself to this two‐hop neighbor. Both processes are lightweight in the sense that the amortized work done per node is constant per round, local, and naturally robust due to the inherent randomized nature of gossip. Our main result is an almost‐tight analysis of the time taken for these two randomized processes to converge. We show that in any undirected n‐node graph both processes take rounds to connect every node to all other nodes with high probability, whereas is a lower bound. We also study the two‐hop walk in directed graphs, and show that it takes time with high probability, and that the worst‐case bound is tight for arbitrary directed graphs, whereas Ω(n²) is a lower bound for strongly connected directed graphs. A key technical challenge that we overcome in our work is the analysis of a randomized process that itself results in a constantly changing network leading to complicated dependencies in every round. We discuss implications of our results and their analysis to discovery problems in P2P networks as well as to evolution in social networks. © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 48, 565–587, 2016     

带凸资源和恶化效应的单机松弛窗口排序

研究带凸资源和恶化效应的单机窗口指派排序问题,其中窗口指的是松弛窗口,凸资源和恶化效应指的是工件的实际加工时间是其开始加工时间的线性函数,是其资源消耗量的凸函数。目标是确定工件的加工顺序,资源分配量以及窗口的开始加工时间和长度使其在总资源消耗费用(与窗口有关的排序费用)有上界限制的条件下,极小化与窗口有关的排序费用(总资源消耗费用)。获得了求解上述问题的最优算法,证明了该问题是多项式时间可解的。     

Timed Petri nets and prediction to improve the Chandy–Misra conservative-distributed simulation

The main contribution of this paper shows that distributed simulation of timed Petri nets (TPN) can take advantage of their structure to obtain a significant lookahead which is usually difficult to compute with other models. In this paper, we introduce a conservative-distributed simulation with a reduced number of control messages and without deadlock resolution. This approach is based on a part of optimism computed on the prediction time each logical process can determine for its advancement. Obviously this prediction time must be computed easily according to the structure of the simulated logical process. Timed Petri nets meet these requirements and we use their structure to evaluate the depth of the prediction. In conservative-distributed simulation, it is known that the deeper the prediction, the better the efficiency of the simulation. We present a method we have devised based on channel time prediction. We compare its performance to the Chandy–Misra method and to some related Petri nets approaches (Chiola). Experiments carried out on Sun stations show that there is more parallelism and a reduced number of null messages in the cases of deadlock avoidance. Moreover, considering deadlock detection and resolution technique we observe that in many cases no deadlock occurs with less control messages.     

人力资源成本预算与控制的理论分析

本的分析是人力资源成本管理体系研究的一部分,着重于探讨在人力资源成本管理体系中,人力资源成本的预算与控制与该体系中其他几部分之间的关系,研究人力资源成本管理实践中成本预算与控制的理论基础,并提出一些新的思路。     

基于博弈论的铁路集装箱中心站装卸作业研究

考虑铁路集装箱中心站不同装卸任务之间的竞争性因素,采用博弈论的方法,研究中心站在客户竞争驱动下的装卸资源调度及作业顺序问题。建立博弈模型并设计遗传算法,通过求解该问题的典型算例,将得到的均衡解与静态最优解进行对比,分析考虑竞争因素的作业方案与最优作业方案的差异。结果表明该方法在对最优方案影响较小的情况下,充分考虑了各装卸任务间的竞争公平性,为中心站确定更加合理的装卸作业顺序和资源调度提供科学的依据。     

北京城市水资源供需系统研究

在研究北京市水资源供需现状的基础上,采用系统动力学方法构建了城市水资源供需模型.利用系统思考中学习型组织的信息反馈回路模式,引入基于可持续发展系统生存回路的水资源供需平衡指标,采用反映供需关系紧张的水供需一次、二次平衡作为衡量地区水危机的变量.按照人口增长与人均综合用水定额不同组合下的城市水需求总量,得到未来北京市水资源供需平衡变化的四种情境,通过动态模拟,分析不同情况下满足水需求的供应方案.结果显示,北京市现有的水资源条件与城市发展需水要求还有较大距离,应在挖掘本地水资源的基础上,依靠南水北调工程等境外调水,解决地区缺水的矛盾.     

Resource constraint scheduling with a fractional shared resource

We consider a scheduling problem motivated by mining in remote off-grid areas. In this model, mines have pre-assigned mineral processing jobs and their own machine for executing these jobs. Each job also needs a certain amount of electricity in order to get completed. The electricity, on the other hand, is of limited supply and must be shared between the mines. We present a mathematical formulation of the problem and a Lagrangian relaxation based heuristic. Computational results which compares our heuristic with genetic algorithm and simulated annealing are also presented.