A multiobjective scatter search algorithm for fault-tolerant NoC mapping optimisation

Mapping IP cores to an on-chip network is an important step in Network-on-Chip (NoC) design and affects the performance of NoC systems. A mapping optimisation algorithm and a fault-tolerant mechanism are proposed in this article. The fault-tolerant mechanism and the corresponding routing algorithm can recover NoC communication from switch failures, while preserving high performance. The mapping optimisation algorithm is based on scatter search (SS), which is an intelligent algorithm with a powerful combinatorial search ability. To meet the requests of the NoC mapping application, the standard SS is improved for multiple objective optimisation. This method helps to obtain high-performance mapping layouts. The proposed algorithm was implemented on the Embedded Systems Synthesis Benchmarks Suite (E3S). Experimental results show that this optimisation algorithm achieves low-power consumption, little communication time, balanced link load and high reliability, compared to particle swarm optimisation and genetic algorithm.     

Reliability- and performance-driven mapping for regular 3D NoCs using a novel latency model and Simulated Allocation

Network-on-Chip (NoC) -based communication architecture is promising in addressing the communication bottlenecks in current and future multicore processors. In this work, we consider the application-specific mapping problem and electromigration (EM) -induced through-silicon via (TSV) reliability issue in tile-based three-dimension (3D) NoC architectures. In 3D NoCs, network contention may result in unacceptable communication delay among the processing cores and thus has significant effect on the system performance. So we propose a new latency model for the routers which characterizes the network contentions among different traffic flows from sharing of network resources. Then we solve the core mapping problem by a fast while efficient stochastic algorithm called Simulated Allocation (SAL), which integrates our new latency model and also aims to optimize the communication power, latency in the mapping procedure. After that, we use an incremental method to optimize the reliability of the TSVs. Experimental results show that, contention-aware model (CAM) has 25% larger network latency than our latency model; compared with particle swarm optimization (PSO), our SAL algorithm can achieve 7% less power with about 7.5 × run-time speedup; as for reliability, our method can achieve better results (up to 10 × increase in terms of the void nucleation time (VNT)) with 7.64% increased latency.     

面向通信能耗的3D NoC映射研究

对于传统的平面结构,三维片上网络(3D NoC)具有更好的集成度和性能,在单芯片内部可以集成更多的处理器核。3D NoC作为2D NoC的结构拓展,在性能提高和低功耗设计方面更具优越性,成为多核系统芯片结构的主流架构。映射就是应用某种算法寻找一种最优方案,将通信任务图的子任务分配到NoC的资源节点上,保证NoC的通信能耗最小。参照2D NoC的研究方法,提出了针对3D网格NoC的通信能耗模型,采用蚁群算法实现了面向通信能耗的NoC映射。实验结果表明,面向不同网络规模的3D网格NoC平台,蚁群映射同随机映射相比,通信能耗降低可以达23%～42%。     

基于包簇框架的云计算能耗优化算法

文中针对以虚拟机为中心的云计算分配模式中结构复杂、分配困难等问题,采用了一种基于包簇结构的分配框架。在此基础上提出了一个有效的能耗模型,并将二进制粒子群算法进行改进,通过调节自适应的权重,提高了包簇分配算法的速度和准确性。实验表明,改进的二进制粒子群算法在收敛速度和寻优能力方面更加优于传统的二进制粒子群算法。相较于以虚拟机为中心的分配算法,基于包簇框架下的改进二进制粒子群分配算法提升了CPU使用率,有效降低了能耗,更加绿色节能。     

D2D通信中基于粒子群优化的能效最大化策略

5G中终端的能量消耗和频谱资源问题日益严重,在终端直通技术(D2D)中尤为突出.为了提高D2D对用户(DP)的能效和资源利用率,提出了一种基于粒子群算法的联合功率控制和资源分配策略.以最大化D2 D链路总能效为目标,将构造的资源分配矩阵和功率分配矩阵作为粒子的位置,依照蜂窝用户(CU)和DP服务质量的约束来修正粒子位置和速度,使之适合于原分式规划问题的求解,合理地提升了DP的总能效,实现了一个DP链路能复用多个CU资源.仿真结果表明,所提算法不仅使能效显著提升,而且使资源利用率提高了80%.     

基于三值多样性粒子群算法的MPRM电路综合优化

通过对离散三值粒子群算法的研究,提出一种三值多样性粒子群算法以求解MPRM（Mixed-Polarity Reed-Muller,MPRM）电路综合优化问题.首先根据混合极性XNOR/OR展开式的特点和几率换算法则,推导出三值粒子群算法的运动方程,在此基础上,采用广泛学习策略和三值变异操作进行算法改进;然后建立三值多样性粒子群算法的粒子与MPRM电路极性的参数映射关系,结合估计模型和XNOR/OR电路混合极性转换方法,将所提算法应用于MPRM电路的最佳功耗和面积极性搜索;最后对10个PLA格式MCNC Benchmark电路进行测试.结果表明：与已发表的方法相比,该文的优化算法表现出了总体显著性的性能优势.     

基于免疫算法的NoC单元映射研究

NOC的发展是解决SOC瓶颈问题的一个方向,而映射问题的解决在NOC设置中是一个很重要的环节。在此研究了广泛使用的二维规则型网（2D-Mesh）建立功耗模型并形成处理单元位置映射。为了改进遗传算法易收敛于局部最优解而采用了免疫算法,并在VC环境下进行仿真,证实了预期的结果,起到了很好的全局寻优效果。     

基于改进PSO的非对称BoucWen模型参数辨识

为了辨识压电陶瓷中的迟滞非线性,该文提出一种改进的粒子群算法(PSO)对非对称BoucWen模型进行参数优化。首先在归一化BoucWen模型中引入非对称因子描述非对称特性,解决该模型只适用于描述对称迟滞的问题。其次通过引入混沌映射、收缩因子和动态学习因子来对传统PSO进行改进,动态改变粒子群的权重和学习因子,有效地提高算法的搜索能力和收敛速度。最后通过改进的PSO对非对称BoucWen模型进行参数辨识。结果表明,改进的粒子群算法能较好地辨识BoucWen模型参数,验证了方法的有效性。     

A multi-objective adaptive immune algorithm for multi-application NoC mapping

Current SoC design trends are characterized by the integration of larger amount of IPs targeting a wide range of application fields. Such multi-application systems are constrained by a set of requirements. In such scenario network-on-chips (NoC) are becoming more important as the on-chip communication structure. Designing an optimal NoC for satisfying the requirements of each individual application requires the specification of a large set of configuration parameters leading to a wide solution space. It has been shown that IP mapping is one of the most critical parameters in NoC design, strongly influencing the SoC performance. IP mapping has been solved for single application systems using single and multi-objective optimization algorithms. In this paper we propose the use of a multi-objective adaptive immune algorithm (M²AIA), an evolutionary approach to solve the multi-application NoC mapping problem. Latency and power consumption were adopted as the target multi-objective functions. To compare the efficiency of our approach, our results are compared with those of the genetic and branch and bound multi-objective mapping algorithms. We tested 11 well-known benchmarks, including random and real applications, and combines up to 8 applications at the same SoC. The experimental results showed that the M²AIA decreases in average the power consumption and the latency 27.3 and 42.1 % compared to the branch and bound approach and 29.3 and 36.1 % over the genetic approach.     

改进粒子群算法优化低功耗自适应集簇分层的路由算法

针对LEA低C功H算法的簇头分布不合理、网络能耗不均的问题,在耗自适应集簇分层路由算法。首先将分割线的选择LE问A题CH转协议的基础上,提出了一种改进粒子群算法优化化成带约束的非线性优化问题,然后利用粒子群算法求解,并针对粒子群算法的不足进行相应的改进,最后采用仿真实验测试算法的性能。仿真结果表明,相对于其它改进LEACH路由算法,本文算法有效提高了网络的能量利用率,能够实现节点之间的能耗均衡,使无线传感器的网络生存时间得到延长。     

考虑可平移负荷的综合能源系统动态优化调度策略

综合能源系统因多能互补、协调优化等特性受到了广泛关注,但该系统的热电机组在运行时的调峰能力具有一定局限性。为降低综合能源系统的用能成本,提升系统的用能效率,改善其调峰能力,文中提出了一种考虑可平移负荷的综合能源系统动态优化调度策略。该策略以系统的整体运维成本最小化为目标,结合可平移负荷和相关算例构建仿真模型,并采用自适应混沌粒子群算法进行求解。结果表明在引入可平移负荷时,多能源微网能够较好地达到削峰填谷目的,并降低系统综合运行成本,实现节能减排效果。同时,文中将传统粒子群算法与自适应混沌粒子群算法作比较,证明了自适应混沌粒子群算法在精度与效率上都优于传统的粒子群算法。     

WSN低功耗低时延路径式协同计算方法

针对云计算应用于无线传感器网络(Wireless Sensor Network,WSN)时延敏感型业务时存在的高传输时延问题,提出了一种WSN低功耗低时延路径式协同计算方法。该方法基于一种云雾网络架构开展研究,该架构利用汇聚节点组成雾计算层;在数据传输过程中基于雾计算层的计算能力分步骤完成任务计算,降低任务处理时延;由于汇聚节点计算能力较弱,时延降低将导致能耗增加,WSN工作寿命减短,为此提出能耗约束下的任务映射策略,并利用离散二进制粒子群优化(Binary Particle Swarm Optimization,BPSO)算法解决能耗约束下的时延优化问题。仿真结果表明,在相同的能耗约束下,对比其他算法,基于BPSO算法得出的映射方案能有效降低业务处理时延,满足时延敏感型业务的需求。     

基于粒子群算法改进的电力系统

本文针对传统粒子群算法自实际应用中出现速度缓慢及局部最优解等等问题,提出了一种改进粒子群算法,并且将其应用在电力系统中,希望能够解决电力系统所存在的例如无功优化等问题中.改进后的粒子群算法在实际应用中收敛速度更加合理,能够有效保证种群的多元性,有效解决传统粒子群所存在的局部最佳解问题.     

不规则2D Mesh NoC映射算法研究

片上网络(NoC)因其分层通讯结构而有望成为未来动态重构片上系统的支撑技术,针对复杂片上系统中可能集成各种规模IP的实际情况,对不规则2D mesh拓扑结构的NoC进行了研究,建立了其映射算法的数学模型和优化目标函数,提出了保证网格不重叠约束条件的数学表达和IP间通信距离的求解方法,采用一个视频解码器实例,给出了映射算法模拟结果和分析,并探讨了布局结果的FPGA实现.     

基于电子搜索算法的电力系统无功优化

针对电力系统无功优化过程中,粒子群算法收敛慢以及计算结果容易陷入局部最优的问题,文中利用电子搜索算法代替粒子群算法,以提高计算的收敛速度并使优化计算更容易得到最优解。以网损期望最小为目标,建立了考虑电容器无功补偿和电压器变比的配电网无功优化模型。利用IEEE14节点系统进行模拟计算,通过结果验证了电子搜索算法在无功优化中的效果。通过比较了粒子群算法和电子搜索算法的结果,证明了电子搜索算法在收敛速度以及优化效果上优于粒子群算法。     

基于粒子群算法的PID控制器参数优化

粒子群算法是一种智能算法,在PID控制器参数整定的应用中可取得更优的效果。为解决传统的粒子群算法早熟收敛和收敛速度慢的缺点,文中采用了一种基于相似度动态调整惯性权重的方法,即越靠近目前最优粒子的个体被赋予越小的惯性权重值。最后用MATLAB对等温连续搅拌釜反应器仿真。与标准的PSO算法整定方法相比,改进的粒子群算法稳定时间为230.1 s,比传统粒子群算法524.7 s的稳定时间缩小了一半,表明改进的算法对PID控制器的参数优化有着较优的收敛效果。     

Synthesis of linear antenna arrays using Jaya,self-adaptive Jaya and chaotic Jaya algorithms

This work aims to show the effectiveness of a recently proposed population-based optimization algorithm known as Jaya algorithm and its variants named as self-adaptive Jaya algorithm (SJaya) and Chaotic-Jaya (CJaya) algorithm to synthesize linear antenna arrays which are widely used in the communication systems. Three case studies of synthesis of linear antenna arrays are formulated by considering different topologies. In addition, two case studies of synthesis of dipole antenna arrays are formulated and all the case studies are solved using Jaya, SJaya and CJaya algorithms. The results of Jaya, SJaya and CJaya algorithms are compared with those of cat swarm optimization (CSO) algorithm, particle swarm optimization (PSO), Cauchy mutated cat swarm optimization (CMCSO) algorithm, harmony search based differential evolution algorithm (HSDEA), dynamic differential evolution algorithm (DDE), improved genetic algorithm (IGA), modified real genetic algorithm (MGA) and accelerated particle swarm optimization (APSO) algorithm. The Jaya, SJaya and CJaya algorithms achieved a better side lobe level suppression as compared to the other optimization algorithms while maintaining the vital antenna parameters within permissible limits.     

基于多维离散粒子群优化的协同 OFDMA 系统跨层资源分配

摘 要：针对多服务情况下协同OFDMA（orthogonal frequency division multiple access）系统的资源分配问题,在基站和中继单独功率约束条件下,以最大化用户的效用(utility)总和为目标,提出了一种基于多维离散粒子群（MDPSO）的渐进最优资源分配算法。该算法采用多值离散变量来编码粒子位置,并针对多维离散空间构建了新的基于概率信息的粒子速度和位置更新算法,且引入变异操作来克服粒子群算法的早熟问题。此外,还采用了迭代注水法进行最优功率分配。仿真结果表明,所提算法在总效用、吞吐量和公平性上均明显优于已有资源分配算法。     

Power Optimization Strategy Considering Electric Vehicle in Home Energy Management System

With the development of smart grid, residents have the opportunity to schedule their household appliances (HA) for the purpose of reducing electricity expenses and alleviating the pressure of the smart grid. In this paper, we introduce the structure of home energy management system (EMS) and then propose a power optimization strategy based on household load model and electric vehicle (EV) model for home power usage. In this strategy, the electric vehicles are charged when the price is low, and otherwise, are discharged. By adopting this combined system model under the time-of-use electricity price (TOUP), the proposed scheduling strategy would effectively minimize the electricity cost and reduce the pressure of the smart grid at the same time. Finally, simulation experiments are carried out to show the feasibility of the proposed strategy. The results show that crossover genetic particle swarm optimization algorithm has better convergence properties than traditional particle swarm algorithm and better adaptability than genetic algorithm.     

改进粒子群优化RBF神经网络在短期电力负荷预测上的研究

电力负荷预测的准确性对整个电力系统的安全和经济效能起着很大的作用,为提高短期电力负荷预测的准确性,提出一种改进的粒子群优化RBF神经网络的模型。针对PSO算法其迭代后期极易深陷部分最优,收敛准确度低,容易发散等问题,提出了PSO算法自身的特性结合Levy飞行机制算法的特点进行融合,在保障算法的寻优准确度的同时也保障了寻优的速度,从而实现全局最优。利用改进的粒子群算法优化RBF神经网络,再将训练好的RBF神经网络应用到电力负荷的预测中。将此模型应用到黑龙江省某地区短期电力负荷预测中,结果表明此种方法有效提高了预测精度。