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991.
针对现有网络的异构性和复杂性以及网络故障监测的需要,研究了用于克服传统故障监测模型中不足的P2P网络通信技术。探讨了用于建立P2P平台的JXTA技术,分析了分布式故障检测的方法,设计了系统原型中数据采集、采用Drools工具的故障告警相关性和拓扑发现模块,实现了基于P2P的分布式网络故障监测系统模型。该系统模型的设计与实现能够有效地降低故障数据对网路带宽的占用率,提高在故障监测中故障数据传输的实时性、准确性和可靠性。 相似文献
992.
993.
In this paper we study the single machine common due date assignment and scheduling problem with the possibility to perform a rate-modifying activity (RMA) for changing the processing times of the jobs following this activity. The objective is to minimize the total weighted sum of earliness, tardiness and due date costs. Placing the RMA to some position in the schedule can decrease the objective function value. Several properties of the problem are considered which in some cases can reduce the complexity of the solution algorithm. 相似文献
994.
We study a single machine scheduling and due-window assignment problem. In addition to the traditional decisions regarding sequencing the jobs and scheduling the due-window, we allow an option for performing a maintenance activity. This activity requires a fixed time interval during which the machine is turned off and no production is performed. On the other hand, after the maintenance time, the machine becomes more efficient, as reflected in the new shortened job processing times. The objective is to schedule the jobs, the due-window and the maintenance activity, so as to minimize the total cost consisting of earliness, tardiness, and due-window starting time and size. We introduce an efficient (polynomial time) solution for this problem. 相似文献
995.
Hybrid flexible flowshops with sequence-dependent setup times and machine availability constraints 总被引:1,自引:0,他引:1
One of the common assumptions in the field of scheduling is that machines are always available in the planning horizon. This may not be true in realistic problems since machines might be busy processing some jobs left from previous production horizon, breakdowns or preventive maintenance activities. Another common assumption is the consideration of setup times as a part of processing times, while in some industries, such as printed circuit board and automobile manufacturing, not only setups are an important factor but also setup magnitude of a job depends on its immediately preceding job on the same machine, known as sequence-dependent setup times. In this paper, we consider hybrid flexible flowshops with sequence-dependent setup times and machine availability constraints caused by preventive maintenance. The optimization criterion is the minimization of makespan. Since this problem is NP-hard in the strong sense, we propose three heuristics, based on SPT, LPT and Johnson rule and two metaheuristics based on genetic algorithm and simulated annealing. Computational experiments are performed to evaluate the efficiencies of the algorithms. 相似文献
996.
Let F be a set of f?2n-5 faulty nodes in an n-cube Qn such that every node of Qn still has at least two fault-free neighbors. Then we show that Qn-F contains a path of length at least 2n-2f-1 (respectively, 2n-2f-2) between any two nodes of odd (respectively, even) distance. Since the n-cube is bipartite, the path of length 2n-2f-1 (or 2n-2f-2) turns out to be the longest if all faulty nodes belong to the same partite set. As a contribution, our study improves upon the previous result presented by [J.-S. Fu, Longest fault-free paths in hypercubes with vertex faults, Information Sciences 176 (2006) 759-771] where only n-2 faulty nodes are considered. 相似文献
997.
The crossed cube, which is a variation of the hypercube, possesses some properties that are superior to those of the hypercube.
In this paper, we show that with the assumption of each node incident with at least two fault-free links, an n-dimensional crossed cube with up to 2n−5 link faults can embed, with dilation one, fault-free cycles of lengths ranging from 4 to 2
n
. The assumption is meaningful, for its occurrence probability is very close to 1, and the result is optimal with respect
to the number of link faults tolerated. Consequently, it is very probable that algorithms executable on rings of lengths ranging
from 4 to 2
n
can be applied to an n-dimensional crossed cube with up to 2n−5 link faults.
相似文献
Gen-Huey ChenEmail: |
998.
Using online simulation in Holonic manufacturing systems 总被引:1,自引:1,他引:0
Olivier Cardin Pierre Castagna 《Engineering Applications of Artificial Intelligence》2009,22(7):1025-1033
This paper deals with the use of online simulation on Holonic manufacturing systems. Concepts needed for the use of online simulation in a classical hierarchical system were already defined, the observer being the central one. The behavior's differences between both classes of systems are studied to determine the best way to adapt these concepts to this new environment. In the product resource order staff approach (PROSA) reference architecture, staff holons were chosen to welcome the simulation models and the observer. An application on an industrial sized Holonic manufacturing system is described to demonstrate the validity of the approach. 相似文献
999.
确保可逆电路的正确性与可靠性,错误检测必不可少,错误定位难度更高.通过分析发现当可逆电路中规模为k的可逆门发生控制点失效时仅对2<'n-k>个输入向量的输出产生影响,据此给出了一种把当前错误集分成若干个子集的方法生成控制点失效错误定位树.传统的错误定位方法都是通过生成真值表和错误表来产生错误定位树;该方法不需要生成和存储真值表以及错误表就能够有效定位电路中控制点失效错误.与Rfault算法相比,空间复杂度和时间复杂度更小,算法效率更高,能应用于更大规模的电路. 相似文献
1000.