软件定义网络中交换机处理时延的仿真

针对目前的网络仿真工具在对软件定义网络(SDN)的仿真过程中,未考虑交换机的处理时延的问题,提出一种处理时延的仿真方法,目的是为了使仿真结果更加真实和准确。该方法首先将交换机的转发处理过程分解为对流表的查询操作和执行不同的动作;然后,利用交换机的处理器频率和访存周期,将查询流表和执行动作转换为处理时间。实验中测量了真实环境中不同配置的交换机处理时延,并与利用该方法仿真出的处理时延进行对比。实验结果表明,利用该方法仿真出的处理时延和真实交换机的处理时延基本一致,该方法能够较准确地仿真交换机处理时延。     

电力系统一二次调频的反馈微分博弈协同控制

风能等间歇式能源并网将是未来电网发展趋势,其输出功率的波动将加剧一二次调频之间的冲突反调问题.本文将反馈微分博弈应用于电力系统频率控制中,建立起一二次调频的协同控制模型,并考虑调速器死区、控制动作幅值限制、机组爬坡速率约束等工程实际因素,用协同进化算法求得该模型的反馈纳什均衡解.用仿真验证了该方法在满足各种工程因素下有效解决一二次调频的冲突反调问题,充分挖掘了系统蕴藏的调频能力.     

基于谈判集的模糊合作博弈的收益分配方案

为了弥补核心作为博弈解可能为空集的缺陷,将经典合作博弈中的谈判集解拓展到模糊合作博弈中,提出了模糊合作博弈的模糊谈判集的概念.探讨模糊网络博弈的模糊谈判集和核心的等价性质,并对相关结论加以证明.研究表明,模糊合作博弈的模糊谈判集是经典合作博弈谈判集的自然拓展,该结果丰富了对模糊合作博弈的解的研究,也表明了模糊网络博弈核心的非空性,进而保证其最优分配方案的存在性.     

网络化雷达协同抗欺骗式干扰技术研究进展

网络化雷达在战场上可以构成全方位、立体化、多层次的战斗体系,因 此对欺骗式干扰对抗具有很大的优越性。本文首先简要介绍了网络化雷达概念,并分析了其 抗干扰优势。根据网络化雷达融合结构不同,将现有协同抗干扰方法分为数据级融合抗欺骗 式干扰和信号级融合抗欺骗式干扰两大类,其中,数据级融合方法进一步分类为点迹关联和 航迹关联两类。本文对各类方法进行了详细介绍,在此基础上,比较分析了数据级融合和信 号级融合两类方法的抗干扰性能及算法复杂度,为抗干扰措施的选择提供依据。最后,针对 现有方法中存在的问题,对网络化雷达协同抗欺骗式干扰的发展趋势进行展望,指出下一步 的研究方向。     

HEAT TRANSFER IN A THIN LIQUID FILM IN THE PRESENCE OF AN ELECTRIC FIELD

Heat transfer enhancement in an evaporating thin liquid film utilizing a electric field under isothermal interfacial condition is presented. A new mathematical model subjected to van der Waals attractive forces, capillary pressure, and an electric field is developed to describe the heat transfer enhancement in the evaporating thin liquid film. The effect of the electrostatic field on the curvature of the thin film, evaporative flux, pressure gradient distribution, heat flux, and heat transfer coefficient in the thin film is presented. The results show that applying an electric field can enhance heat transfer in a thin liquid film significantly. In addition, utilizing electric fields on the evaporating film will be a way to expand the extended meniscus region to attain high heat transfer coefficients and high rates of heat flux.     

氯化胆碱合成工艺的研究

在氯化胆碱的作用下,三甲胺与氯乙醇反应合成氯化胆碱。讨论了影响产品收率及纯度的主要因素。实验发现氯化胆碱有自催化作用,在优化工艺条件下,氯化胆碱的收率达到95.8%,纯度达到98.0%。该工艺具有操作简单、易分离、易干燥、收率高、纯度高、成本低、易推广等优点。     

A progressive deployment strategy for cooperative adaptive cruise control to improve traffic dynamics

Cooperative adaptive cruise control(CACC)vehicles are intelligent vehicles that use vehicular ad hoc networks(VANETs)to share trafc information in real time.Previous studies have shown that CACC could have an impact on increasing highway capacities at high market penetration.Since reaching a high CACC market penetration level is not occurring in the near future,this study presents a progressive deployment approach that demonstrates to have a great potential of reducing trafc congestions at low CACC penetration levels.Using a previously developed microscopic trafc simulation model of a freeway with an on-ramp—created to induce perturbations and trigger stop-and-go trafc,the CACC system s efect on the trafc performance is studied.The results show signifcance and indicate the potential of CACC systems to improve trafc characteristics which can be used to reduce trafc congestion.The study shows that the impact of CACC is positive and not only limited to a high market penetration.By giving CACC vehicles priority access to high-occupancy vehicle(HOV)lanes,the highway capacity could be signifcantly improved with a CACC penetration as low as 20%.     

A Progressive Deployment Strategy for Cooperative Adaptive Cruise Control to Improve Trafc Dynamics

Cooperative adaptive cruise control(CACC)vehicles are intelligent vehicles that use vehicular ad hoc networks(VANETs)to share trafc information in real time.Previous studies have shown that CACC could have an impact on increasing highway capacities at high market penetration.Since reaching a high CACC market penetration level is not occurring in the near future,this study presents a progressive deployment approach that demonstrates to have a great potential of reducing trafc congestions at low CACC penetration levels.Using a previously developed microscopic trafc simulation model of a freeway with an on-ramp—created to induce perturbations and trigger stop-and-go trafc,the CACC system s efect on the trafc performance is studied.The results show signifcance and indicate the potential of CACC systems to improve trafc characteristics which can be used to reduce trafc congestion.The study shows that the impact of CACC is positive and not only limited to a high market penetration.By giving CACC vehicles priority access to high-occupancy vehicle(HOV)lanes,the highway capacity could be signifcantly improved with a CACC penetration as low as 20%.     

液固分离技术的进展

本文简述了液固分离技术近年来的进展。特别涉及加压电过滤设备、毛细吸附作用下的真空过滤机、动态过滤技术、新型卧式螺旋卸料沉降离心机、滤材等方面技术的国内外进展情况。     

自适应收扩系数的双中心协作QPSO算法

针对量子粒子群优化(QPSO)算法迭代后期种群多样性下降、收敛速度慢、易陷入局部最优的缺点,提出一种自适应收缩-扩张系数的双中心协作最子粒子群优化算法。该算法从2个方面进行改进:(1)自适应调节收缩-扩张系数,其目的是帮助粒子跳出局部最优点,提高粒子的全局搜索能力;(2)双重更新全局最优位置,即在每次迭代中,先后分别采用2种不同的方式更新全局最优位置。第1种方式与QPSO算法一致,第2种方式则引入双中心粒子,使其和当前全局最优位置在相应维度上合作,从而达到更新全局最优位置的目的。从固定迭代次数和固定精度角度分析算法性能,仿真结果表明,相比于QPSO算法,该算法在保证复杂度较低的情况下,可提高收敛速度,增强全局和局部搜索能力。