订货与发货整合批量调度问题

在对文题进行数学描述的基础上，建立求解该类问题的混合整数线性规划模型.证明问题NP 困难性并研究多项式可解子问题，进一步提出了3个启发式算法以及精确求解的分支定界算法.数值实验表明，所提出启发式算法以及分支定界算法的有效性与高效性.     

Distributed link scheduling method with physical interference model in wireless multi-hop networks

To further increase the throughput of wireless multi-hop networks,a distributed scheduling method is proposed,which takes physical interference model into account.It is assumed that nodes in the network can perform physical carrier sensing,and the carrier sensing range can be set to different values.In the traditional carrier sensing mechanism,the carrier sensing range is computed under the protocol interference model,which is not accurate.Here the optimal carrier sensing range with physical interference model is achieved.Each sending node implements the distributed approach in three phases at each time slot,and all the concurrent transmissions are interference free.Good performance can be achieved under this scheduling approach.The approximation ratio of the distributed method to the optimal one is also proved.     

IEEE802.16 Mesh协同分布式模式下的延迟性能分析

为了更好地对IEEE802.16 Mesh协同分布式模式下的网络时延进行评估,利用已有的随机分布式模型,在介绍了IEEE802.16 Mesh的MAC帧格式的基础上,对接入延迟和3次握手的延迟进行了性能分析和仿真分析。分析结果表明,随着回退时隙数量的增加,MSH-DSCH消息的接入延迟和3次握手延迟会增加,仿真结与理论分析结果相同。     

服装供应商制造周期效能的提高及案例分析:订单排程与投料管控

以服装供应商——牛仔服加工厂改善制造周期效能为例,着重分析生产订单排程与合理投料的流程改进与优化.通过合理的订单排程、确定缓冲时间、根据缓冲状态管理优先顺序、管控投料等方法,为服装供应商实现缩短生产周期、准时交货以及增加有效产出提供可行性实施方案.     

加工能力受扰的可控排序干扰管理

在加工时间可控的单机排序中,面对随机发生的干扰事件,研究了初始加工时间表的制定问题。对于干扰事件造成的影响采用匹配时间排序的应对策略,在干扰事件发生后,通过压缩工件加工时间,使新时间表在某时间点后完全恢复到初始加工时间表。基于工件吸收干扰事件影响的能力,设计复合排序规则来决定工件的优先级。由于问题内在的复杂性,在复合排序规则中,应用遗传算法来确定某给定待处理工件集的最优参数。使用概率分布表示干扰事件的发生时刻和持续时间,并综合概率信息和工件的优先级来制定初始加工时间表。最后,通过随机数值试验模拟,发现本文设计的初始时间表优于根据最短加工时间优先规则制定的初始时间表,验证了方法对于处理干扰事件影响的有效性。     

单机E/T调度问题的动态规划新解法

本文利用最优调度的目标函数的性质，放弃了参数为整数的假定，改进了求解单机的Ｅ／Ｔ调度问题的动态规划算法，使其在时间复杂度和空间复杂度两方面都有提高     

一类装配式流水作业排序问题的启发式算法及其性能比研究

根据Ｆ′２｜ｍ１≥２，ｍ２＝１｜Ｃｍａｘ排序问题是ＮＰ完全问题的论断，提出了ＡＦＳ问题的两个启发式算法，分别给出了应用启发式算法的实例，并证明了该启发式算法在最坏情况下的品性是２的结论     

求解多目标作业排序问题的遗传算法

利用联合进化遗传算法 ( CEGA)建立了求解多目标排序问题的一般框架 ,采用目标权衡分析诱导出决策人的偏好关系 ,并将其引入求解过程 ,以确定满意排序 ,在搜索寻优过程中 ,将启发式与遗传算法相结合 ,以提高搜索效率 .最后 ,利用该算法框架求解了一个含调整时间的一般 Job Shop排序问题 ,以表明算法的有效性.     

Slack-nibbling battery-aware task scheduling

Dynamic voltage scaling (DVS) is an efficient approach to maximize the battery life of portable devices. A novel overall planning strategy (OPS II) balancing slack supply and demand for DVS is proposed. An OPS II-based slack-nibbling overall planning strategy (SNOPS) algorithm is also proposed, which iteratively nibbles slacks for appropriate tasks selected by an overall planning dynamic priority function to perform DVS until the slack is exhausted and an optimum voltage setting is obtained. For a high-load task set, SNOPS manages to recover battery overload while maintaining schedulability. For random variable-load task sets, SNOPS achieves a saving of 29.51% battery capacity on average, the suboptimal gap is 27.84% narrower than that of our previously proposed OPS-based algorithm, and 92.10% narrower than that of the algorithm proposed by Chowdhury et al. Results indicate that OPS II manages to save battery to various extents while maintaining schedulability, and demonstrates good load compatibility and close-to-optimal performance on average. Biography: GAO Xun(1981–), male, Ph.D. candidate, research direction: embedded system, power optimization.     

Concurrent transmission with minimal SR-pair interference in WiMAX mesh networks

Performance of wireless mesh networks can be greatly improved by spatial reuse (SR), therefore, lots of algorithms have been proposed to maximize the number of concurrent transmissions. However, most methods only considered the interference brought by the sender nodes. In this paper, we study the interference model in WiMAX mesh networks and propose a minimal SR-pair interference model to perform concurrent transmissions in both uplink and downlink directions. Simulation results show that our model is more efficient and stable, i.e., it increases the number of concurrent transmissions and its performance is constant and independent of transmission directions. Biography: XIONG Qing(1978–), male, Ph. D., research direction: wireless mesh networks.