IBM370系统的双地址空间设备

双地址空间设备 DAS(dual address spacefacility)属于IBM370系统的扩充控制程序支持 Ecps:mvs。多虚存/系统产品(mvs/sp)中的交叉存贮器服务(cross memory service)利用DAS改善了mvs之间的连接和通讯。由此减少了虚存中的系统需要量,从而增加了应用     

缓解异构MPSoC电迁移效应的任务调度算法EI北大核心CSCD

随着集成电路制造工艺进入到纳米时代,日益严重的电路老化给多处理器片上系统(MPSo C)可靠度带来严峻挑战.针对在性能异构MPSo C中,已有的可靠度优化方法没有考虑处理器之间的可靠度差异的问题,提出一种减小处理器可靠度差异的任务调度算法.该算法结合电迁移效应下单个处理器的平均无故障时间模型分析了制约单个处理器可靠度的因素,得出性能异构MPSo C中处理器可靠度差异模型;基于此差异模型,提出一种交叉分配任务调度算法——cross,减小了处理器间可靠度差异,达到整体优化可靠度的目的.实验结果表明,与已有的均衡受压任务调度算法相比,cross任务调度算法下异构MPSo C中处理器的平均无故障时间变异系数降低了3.71%.     

缓解异构MPSoC电迁移效应的任务调度算法

随着集成电路制造工艺进入到纳米时代,日益严重的电路老化给多处理器片上系统(MPSo C)可靠度带来严峻挑战.针对在性能异构MPSo C中,已有的可靠度优化方法没有考虑处理器之间的可靠度差异的问题,提出一种减小处理器可靠度差异的任务调度算法.该算法结合电迁移效应下单个处理器的平均无故障时间模型分析了制约单个处理器可靠度的因素,得出性能异构MPSo C中处理器可靠度差异模型;基于此差异模型,提出一种交叉分配任务调度算法——cross,减小了处理器间可靠度差异,达到整体优化可靠度的目的.实验结果表明,与已有的均衡受压任务调度算法相比,cross任务调度算法下异构MPSo C中处理器的平均无故障时间变异系数降低了3.71%.     

基于语境辅助转换器的图像标题生成算法

在图像标题生成领域,交叉注意力机制在建模语义查询与图像区域的关系方面,已经取得了重要的进展.然而,其视觉连贯性仍有待探索.为填补这项空白,提出一种新颖的语境辅助的交叉注意力(Context-assisted cross attention,CACA)机制,利用历史语境记忆(Historical context memory, HCM),来充分考虑先前关注过的视觉线索对当前注意力语境生成的潜在影响.同时,提出一种名为“自适应权重约束(Adaptive weight constraint, AWC)”的正则化方法,来限制每个CACA模块分配给历史语境的权重总和.本文将CACA模块与AWC方法同时应用于转换器(Transformer)模型,构建一种语境辅助的转换器(Context-assisted transformer, CAT)模型,用于解决图像标题生成问题.基于MS COCO(Microsoft common objects in context)数据集的实验结果证明,与当前先进的方法相比,该方法均实现了稳定的提升.     

一种基于CHC算法的自动组卷方法*

利用改进的遗传算法——跨世代异物种重组大变异(cross generation heterogeneous recombination cataclysmic mutation,CHC)算法提出了一种自动组卷方法。初始种群即初始试卷集利用具有启发式信息的搜索算法产生;适应度函数是用户指定的试卷总体指标与试卷实际指标绝对误差的加权和;选择操作群体为当前群体与上世代群体的群体总和,因为大个体群操作可以更好地保持遗传多样性;交叉操作采用单点交叉方法。变异操作的步骤是：从上世代个体中挑选适应度较差的个体,对其中的     

离散蝙蝠算法在三阶段装配流水线调度问题的应用

针对数据包络分析(DEA)交叉效率方法大多是面向结果采用平均方式集结交叉效率,没有考虑评价过程中属性效用数据及其变动的特性,导致大量决策信息丢失、相对效率评价值与被评价决策单元的指标值关联性不够等问题,以交叉效率评价过程为导向,引入群决策理论,研究属性偏好及其属性效用变化特征,运用熵权法分析属性效用稳定性,发现评价中存在属性效用的熵及其熵权的唯一性性质,从而将各决策单元(DMU)的自评权重(个体偏好)集结为一个DEA评价系统的群权重(DEA系统偏好或群偏好),建立仅有一组公共权重的群决策他评交叉效率评价方法.该方法面向过程,依据他评交叉属性效用稳定性区分其在评价中的作用,用群决策他评交叉综合群效用替代交叉效率平均作为相对效率评价值,变结果导向的交叉效率集结为过程导向的权重偏好集结,实现将相对效率评价值与群权重和属性指标值直接关联.改进后的方法简洁直观,同时方便寻求改善相对效率的途径.最后,通过算例分析验证了所提出方法的可行性与有效性.     

双层交叉细胞自动机的伪随机数发生方法

提出一种基于两层交叉细胞自动机(twi-layer cross cellular automa,TLCCA)结构的伪随机发生器(pseudorandom numbers generator, PRNG).TLCCA的复杂性介于一维细胞自动机与二维细胞自动机之间,而且输出方式简单;细胞间采用了一种新的对称交叉式的邻居关系,该结构一方面保证了对称性,另一方面减少了相邻细胞间的相关性.并利用多目标遗传算法对邻居关系结构进行了优化,最终的实验结果表明该结构的PRNG可以高效地生成高质量的伪随机数,而且易于用硬件实现.     

基于交叉熵的改进NPE间歇过程故障检测算法

针对具有复杂动态特性的间歇过程进行故障检测,邻域保持嵌入(neighborhood preserving embedding,NPE)算法在保持数据局部几何结构时因忽略全局信息而造成检测率较低的问题,提出一种基于交叉熵(cross entropy,CE)的邻域保持嵌入(CEGLNPE)算法.首先,将交叉熵保持全局结构的思想引入NPE的局部结构保持中,得到兼顾全局-局部的目标函数;然后,利用滑动窗进一步解决间歇过程动态性问题并建立全局-局部的故障检测模型,可以同时兼顾全局和局部数据的结构保持,以提高故障检测效率和精度;最后,通过监测SPE、T²统计量判断是否发生故障.利用人工数据集Swiss-Roll和青霉素发酵仿真过程与KPCA、NPE算法进行对比验证,所得结果表明了所提出算法在故障检测中的有效性.     

基于深度可分离卷积和交叉注意力的水面污染识别

水面污染严重影响水面景观和水体生态. 针对识别水面污染过程中水面场景复杂、小目标污染物特征难以提取等问题, 本文提出一种基于深度可分离卷积与交叉注意力算法模块(deep-wise convolution and cross attention, DCCA). 使用深度可分离卷积降低模型的参数量和计算量, 使用交叉注意力建立不同尺度特征图之间的关系, 使模型更好地理解上下文信息并提高识别复杂场景和小目标的能力. 实验结果表明, 添加DCCA模块后平均精确率提升了1.8%, 达到了88.7%. 并使用较少的显存占用提高了水面污染的检测效果.     

基于证据理论-DEA 交叉效率的混合型多属性决策方法

针对含有投入产出指标的混合型多属性决策问题,提出一种基于证据理论和数据包络分析(DEA)交叉效率的决策方法.首先运用DEA对决策系统中投入产出指标进行处理,得到DEA交叉效率矩阵,并运用证据理论集结其交叉效率得分;然后将效率得分作为决策系统指标值,与系统中其他指标进行模糊等级转换,通过证据理论对指标值融合,进而得到决策单元的期望效用,据此对决策单元进行排序;最后通过实例与其他文献方法进行对比分析,以表明所提出方法的可行性和有效性.     

Adaptive backstepping control of uncertain systems with unknown input time-delay

In this paper, we establish the robustness of adaptive controllers designed using the standard backstepping technique with respect to unmodeled dynamics involving unknown input time delay. While noting that some results on robust stabilization of non-minimum phase systems using the backstepping technique are available, we realize that the standard adaptive backstepping technique has only been shown applicable to unknown minimum phase systems. Another significance of our result is to enable the class of systems stablizable by adaptive backstepping controllers to cross the boundary of minimum phase systems, since systems with input time delay belong to non-minimum phase systems. Moreover, the L₂ and L_∞ norms of the system output are also established as functions of design parameters. This implies that the transient system performance can be adjusted by choosing suitable design parameters.     

非匹配不确定非线性系统的自适应反演滑模控制

针对一类具有非匹配不确定性的最小相位仿射非线性系统,研究其在未知扰动作用下的调节问题。基于自适应反演设计方法和变结构控制设计了控制方案,实现不确定系统的鲁棒调节。与经典反演设计相比,本方案允许非参数化不确定性,增强了控制系统的鲁棒性。     

On the backstepping design procedure for multiple input nonlinear systems

In a recent paper, we developed a structural decomposition for multiple input multiple output nonlinear systems that are affine in control but otherwise general. In this paper, we exploit the structural properties of such a decomposition in the application of the backstepping design technique on multiple input nonlinear systems. In particular, this decomposition simplifies the conventional backstepping design and motivates new backstepping design procedures that are able to stabilize systems on which the conventional backstepping procedure is not applicable. Copyright © 2011 John Wiley & Sons, Ltd.     

A sum of squares approach to backstepping controller synthesis for piecewise affine and polynomial systems

This paper develops a backstepping controller synthesis methodology for piecewise polynomial (PWP) systems in strict form. The main contribution of the paper is to formulate sufficient conditions for controller design for PWP systems in strict form as a sum of squares feasibility problem under the assumption that an initial control Lyapunov function exists to start the iterative backstepping procedure. This problem can then be translated into a convex SDP problem and solved by available software packages. The controller synthesis problem for PWP systems in strict feedback form is divided into two cases. The first case consists of the construction of a sum of squares polynomial control Lyapunov function for PWP systems with discontinuous vector fields. The second case addresses the construction of a PWP control Lyapunov function for PWP systems with continuous vector fields. One major advantage of the proposed method is the fact that it can handle systems with discontinuous vector fields and sliding modes. The new synthesis method is applied to several numerical examples. One of these examples offers the first convex optimization solution to piecewise affine (PWA) control of a benchmark circuit system addressed before in the literature using non‐convex PWA control solutions. Copyright © 2013 John Wiley & Sons, Ltd.     

随机非线性系统鲁棒自适应反馈控制器的积分反推方法设计

考虑了一类随机非线性系统的鲁棒自适应控制问题.采用Ito随机微分方程描述系统, 进而在概率意义下研究系统的鲁棒稳定性.应用积分反推(backstepping)方法,系统地给出了设 计状态反馈及输出反馈鲁棒自适应控制器的方法.同时构造出了适当形式的四次型的自适应控 制Lyapunov函数(CLF).     

Motion/force tracking control of nonholonomic mechanical systems via combining cascaded design and backstepping

This paper considers motion/force tracking control of a class of Lagrange mechanical systems with classical nonholonomic constraints. A tracking control method is proposed by combining cascaded methods and backstepping techniques. The main results of this paper include three parts: (1) error dynamics between the kinematic system and the desired paths are transformed into a cascaded system consisting of two subsystems and an interconnection function; (2) under the framework of cascaded methods, virtual controllers for the subsystems are designed to stabilize the error dynamics; (3) the tracking controller is designed for the overall mechanical systems using backstepping techniques.     

Event‐triggered adaptive backstepping control for parametric strict‐feedback nonlinear systems

This paper proposes a novel adaptive backstepping control method for parametric strict‐feedback nonlinear systems with event‐sampled state and input vectors via impulsive dynamical systems tools. In the design procedure, both the parameter estimator and the controller are aperiodically updated only at the event‐sampled instants. An adaptive event sampling condition is designed to determine the event sampling instants. A positive lower bound on the minimal intersample time is provided to avoid Zeno behavior. The closed‐loop stability of the adaptive event‐triggered control system is rigorously proved via Lyapunov analysis for both the continuous and jump dynamics. Compared with the periodic updates in the traditional adaptive backstepping design, the proposed method can reduce the computation and the transmission cost. The effectiveness of the proposed method is illustrated using 2 simulation examples.     

一类欠驱动系统的非线性输出跟踪控制

针对一类模型结构为非下三角的欠驱动系统,在反步法的框架下研究了其非线性输出跟踪控制问题．鉴于在此类欠驱动系统的反步法设计中,沿用一般下三角系统的偏差难以镇定全部的偏差动态,由此引入了“联系函数”的概念．在反步法设计中,构造了异于下三角系统的偏差,设计了状态反馈跟踪控制器,保证了系统偏差的全局一致渐近稳定性．仿真结果表明...     

Robust stabilization for nonholonomic systems with state delay and nonlinear drifts

This paper presents a control strategy for stabilization of the nonholonomic control systems with strongly nonlinear drifts and state delay.Applying a novel Lyapunov functional and backstepping recursive method,the design of robust nonlinear state feedback controllers is proposed,which can guarantee the stability of the closed-loop systems.Finally,a numerical example is provided to show the effectiveness of the method.     

Robust adaptive backstepping control for a class of uncertain nonlinear systems based on disturbance observers

In this paper, a novel robust adaptive control scheme for a class of uncertain nonlinear systems is proposed using disturbance observer and backstepping method.Firstly, a disturbance observer is developed using radial basis function(RBF) neural network.The parameter updated law of the RBF neural network is given for monitoring subsystem disturbance well.The robust adaptive control scheme is then presented with backstepping method based on the designed disturbance observer.Semiglobal uniform ultimate bounded...