基于状态观测器的伪非线性系统的镇定设计

对非线性系统进行分析，首先通过一个简单例子说明对于非线性系统研究用估计状态进行设计的必要性，然后对伪非线性系统给出了用估计状态进行镇定的有关结论，最后举例说明基于估计状态的非线性控制器的设计方法。     

广义离散随机线性系统的降阶估计

该文讨论广义离散随机线性系统的状态估计问题，给出了一种降阶估计方法，该方法可直接估计系统的部分状态或系统状态的某个线性组合．     

广义离散随机线性系统的降价估计

该文讨论广义离散随机线性系统的状态估计问题,给出了一种降阶估计方法,该方法可直 接估计系统的部分状态或系统状态的某个线性组合.     

2-D线性离散系统一般模型的最优状态估计*

本文利用最优状态估计理论，讨论了二维线性离散系统一般模型最优状态估计问题，基于２－ＤＧＭ的变结构１－Ｄ表示，导出了表现为１－Ｄ形式的２－ＤＧＭ的最优状态估计器，文中还直接由２－ＤＧＭ出发，将１－Ｄ最优状态估计的思想推广到２－Ｄ情形，提出了２－Ｄ状态估计器的设计方法。     

MIMO非线性系统状态估计的递推Monte-Carlo方法研究

递推蒙特·卡洛 (Monte-Carlo,MC)方法是基于系统状态和观测值概率分布的估计方法。本文首先讨论了SISO非线性系统状态估计中递推 MC方法的应用 ,在此基础上将上述状态估计方法推广到 MIMO非线性系统 ,并提出了两种不同的估计方案。仿真研究表明 ,这两种方案都可以得到较好的状态估计结果。不过 ,随机抽样数目对递推 MC估计方法的状态估计精度会产生较大影响 ,限制了该方法的进一步应用 ;本文对随机抽样数目对状态估计结果的影响进行了讨论。     

量子系统中状态估计方法的综述

从广泛用于实验量子领域的典型状态估计方法,到基于系统论观点、可用于量子反馈控制的状态估计方法,详细综述了4种测量方式下的相应量子状态估计方法及其适用背景.通过其发展历程的叙述,从本质上阐述了估计的基本原理,从技术上对各种方法进行了相应的分析和比较.同时,对量子状态估计和经典状态估计进行了相应的比较,并对量子系统中的状态估计方法作了总结.     

广义离散随机线性系统最优滤波·预报和平滑估计的统一格式

本文运用新息和射影的方法研究了广义离散线性系统最优状态估计，将状态估计转化为输出预报估计和白噪声估计，提出了广义离散随机线性系统最优滤波、预报、平滑估计的统一格式。     

神经网络在状态估计中的应用

本文提出了一种基于神经网络的状态估计方法,避开了依靠数学模型的传统途径,为在那些建模困难的场合实现状态估计提供了可能,仿真结果令人满意.     

非线性离散随机时变系统比例微分滤波

扩展卡尔曼滤波（EKF）是从极小化状态估计误差的方差得到的，没有考虑状态误差的变化率，因而对非线性时变系统EKF估计方法惯性作用 较大，从而产生估计滞后，提出了非线性离散随机系统比例微分滤波（PDF），PDF联合考虑极小化状态估计误差和状态误差变化率的方差，克服了EKF对非线性时变系统估计滞后的缺点，估计具有适时性，提出了高估计的精度，仿真例子证明了所提出的估计方法的有效性。     

基于交互容积卡尔曼的随机切换系统故障诊断

针对一类随机切换非线性系统的故障检测和故障估计问题,提出了一种基于交互式多模型和容积卡尔曼滤波（IMM CKF）的系统状态估计算法。该算法利用容积卡尔曼滤波（CKF）在不同时刻对每个子系统进行状态估计,把不同子系统状态估计结果融合得到最终的状态估计,实现对系统真实状态的估计。针对一类随机切换非线性系统发生执行器故障,采用IMM CKF估计系统状态;然后分析了IMM CKF算法的稳定性;根据状态估计结果,构造残差信号,设计残差评价函数,检测故障发生。当检测到故障发生时,设计增广系统,对故障幅值进行估计。通过仿真实验验证提出算法的有效性,结果表明该算法可以较为准确地诊断系统故障。     

The boundaries for joint angles of isocomfort for sitting and standing males based on perceived comfort of static joint postures

This study presents data for the joint angles of isocomfort (JAI) in sitting and standing males based on perceived comfort ratings for static joint postures maintained for 60 s. The JAI value was defined as a boundary indicating joint deviation (an angle) from neutral posture, within which the perceived comfort for different body joint postures is expected to be the same. An experiment for quantifying perceived comfort ratings was conducted using the free modulus method of magnitude estimation. Based on experimental results, regression equations were derived for each joint posture, to represent the relationships between different levels of joint deviation/joint posture and corresponding normalized comfort scores. The JAI values were developed for nine verbal categories of joint comfort. The JAIs with the marginal comfort levels, one of the nine verbal categories used, for most joint postures around the wrist, elbow, neck and ankle were similar to the maximum range of motion (ROM) values for these joints. However, the JAIs with the marginal comfort category for back and hip postures were much smaller than the maximum ROM values for these joints. There were no significant differences in JAI expressed in terms of the percentage of the corresponding maximum ROM values between sitting and standing postures. The relative 'marginal comfort index', defined as the percentage of JAIs for the marginal comfort relative to the corresponding maximum ROM values, for the hip was the smallest among all joints. This was followed, in an increasing order of the marginal comfort index, by the lower back and shoulder, while the marginal comfort index for the elbow joint was the largest. The results of this study suggest that static postures maintained for 60 s cause greater discomfort for the hip joint than for the other joints studied, and less discomfort for the elbow than for the other joints. The data about JAIs can be used as guidelines for enhancing postural comfort when designing a variety of human-machine tasks where static postures cannot be eliminated.     

Meme Media for Clipping and Combining Web Resources

The publication and reuse of intellectual resources using the Web technologies provide no support for us to clip out any portion of Web pages, to combine them together for their local reuse, nor to publish the newly composed object as a new Web page for its reuse by other people. This paper shows how the meme-media architecture is applied to the Web to provide such support for us. This makes the Web work as a shared repository not only for publishing intellectual resources, but also for their collaborative reediting. We will propose a general framework for clipping arbitrary Web contents as live objects, for defining IO ports on such a clip, and for the recombination and linkage of such clips based on both the original and some user-defined relationships among them. In our previous works, we proposed two separate frameworks for these three purposes; one works for the first two, and the other for the last. Here we will propose a unified framework for these three purposes, as well as its detailed internal mechanisms. Then we show how it can be easily applied to various legacy Web applications to develop innovative services.     

Estimating the Attraction Domain for the Boost Inverter

This work presents an approach for estimating the domain of attraction for polynomial systems with state and control‐signal constraints, including saturation. In many problems, it is possible to derive global stability properties for such systems, neglecting constraints. Consideration of the constraints usually makes the problem much more complicated. In this paper, the stability analysis performed for the unconstrained case is used for the problem as a whole. For application of the method, there are powerful computational tools that can be employed in cases of polynomial systems. The technique is not only valid for the analysis of equilibrium points, but also for other attractors, such as limit cycles. As examples, the domain of attraction for given control laws is estimated for both a nonlinear DC‐DC boost converter and for a boost inverter.     

基于多反应节点下WSANs路由协议研究

针对多个反应节点环境中现有无线传感器网络路由协议不能完全满足无线传感反应网络（WSANs）对能耗和实时性需求的问题,利用J-Sim对WSANs的仿真功能,设计并实现适应单反应节点选择模式的WSANs路由协议BHOER,给出仿真数据及性能分析,实验结果表明,BHOER较好地满足WSANs的应用需求。     

一种分布动态网络安全系统框架

网络是人类社会全新的活动空间。这个活动空间必须符合人类社会活动的规则。信息安全是其中最重要的问题。安全问题不是某个使用网络部门的事,而是需要全社会合力解决的问题。本文从入侵检测信息的标准化入手,提出了一个分布动态网络安全系统框架结构。探讨了分布动态网络安全系统框架的层次结构、通讯方式和协议,通过分布动态网络安全系统框架解决攻击源定位、攻击响应及重要应用系统的防护等问题。     

A lattice Boltzmann method for immiscible two-phase Stokes flow with a local collision operator

We propose a lattice Boltzmann model for immiscible two-phase Stokes flow with a local collision operator. The model is based on two different lattice Boltzmann automata, one for the flow field and one for an indicator function for the two different phases. The model is described in detail and verified by the following test-cases: a static bubble for the surface tension, a closed capillary tube for the contact angle and two phase flow in a concentric annulus for the viscosity ratio. In the appendix an asymptotic analysis for the derivation of the two-phase Stokes equation is given.     

An analysis of thematic mapper simulator data for urban environments

Thematic mapper simulator data collected for the Los Angeles Basin in 1980 were examined to assess their utility for urban and near-urban land-cover delimitations. Spectral data for six of the thematic mapper channels were reprojected to a UTM grid and aggregated to 30-m resolution, 120 m for the thermal band. Statistics for 21 training sites representing 8 land-cover types were obtained and examined using transformed divergence calculations for intraclass variability, optimal number of channels for classification, and best channels for classification. Four channels of data are adequate for classification with the best results obtained by selection of one channel from each of the available major portions of the electromagnetic spectrum. The thermal channel data is useful for urban land-cover delineations at 30-m resolution, but its utility at 120-m resolution is not clear from this study.     

Generation of Positive and Negative Tests for Parsers

A methodology for automatic positive and negative test set generation for testing parsers is described. Coverage criteria for such test sets based on the model approach to testing are proposed. Methods for the generation of test sets satisfying these criteria are discussed. Results of the application of the proposed methodology for testing parsers for various languages including C and Java are presented.     

The boundaries for joint angles of isocomfort for sitting and standing males based on perceived comfort of static joint postures

This study presents data for the joint angles of isocomfort (JAI) in sitting and standing males based on perceived comfort ratings for static joint postures maintained for 60 s. The JAI value was defined as a boundary indicating joint deviation (an angle) from neutral posture, within which the perceived comfort for different body joint postures is expected to be the same. An experiment for quantifying perceived comfort ratings was conducted using the free modulus method of magnitude estimation. Based on experimental results, regression equations were derived for each joint posture, to represent the relationships between different levels of joint deviation/joint posture and corresponding normalized comfort scores. The JAI values were developed for nine verbal categories of joint comfort. The JAIs with the marginal comfort levels, one of the nine verbal categories used, for most joint postures around the wrist, elbow, neck and ankle were similar to the maximum range of motion (ROM) values for these joints. However, the JAIs with the marginal comfort category for back and hip postures were much smaller than the maximum ROM values for these joints. There were no significant differences in JAI expressed in terms of the percentage of the corresponding maximum ROM values between sitting and standing postures. The relative ‘marginal comfort index’, defined as the percentage of JAIs for the marginal comfort relative to the corresponding maximum ROM values, for the hip was the smallest among all joints. This was followed, in an increasing order of the marginal comfort index, by the lower back and shoulder, while the marginal comfort index for the elbow joint was the largest. The results of this study suggest that static postures maintained for 60 s cause greater discomfort for the hip joint than for the other joints studied, and less discomfort for the elbow than for the other joints. The data about JAIs can be used as guidelines for enhancing postural comfort when designing a variety of human-machine tasks where static postures cannot be eliminated.     

Muscle response to pneumatic hand tool torque reaction forces

Surface electromyography was used for studying the effects of torque reaction force acting against the hand, on forearm muscle activity and grip force for five subjects operating right angle, air shut-off nutrunners. Four tools having increasing spindle torque were operated using short and long torque reaction times. Nutrunner spindle torque ranged between 30 Nm and 100 Nm. Short torque reaction time was considered 0.5 s while long torque reaction time was 2 s. Peak horizontal force was the greatest component of the reaction force acting against the hand and accounted for more than 97% of the peak resultant hand force. Peak hand force increased from 89 N for the smallest tool to 202 N for the largest tool. Forearm muscle rms EMG, scaled for grip force, indicated average flexor activity during the Torque-reaction phase was more than four times greater than the Pre-start and Post Shut-off phases, and two times greater than the Run-down phase. Flexor EMG activity during the Torque-reaction phase increased for increasing tool peak spindle torque. Average flexor rms EMG activity, scaled for grip force, during the Torque-reaction phase increased from 372 N for the 30 Nm nutrunner to 449 N for the 100 Nm nutrunner. Flexor rms EMG activity averaged during the Torque-reaction phase and scaled for grip force was 390 N for long torque reaction times and increased to 440 N for short torque reaction times. Flexor rms EMG integrated over the torque reaction phase was 839 Ns for long torque reaction times and decreased to 312 Ns for short torque reaction times. The average latency between tool spindle torque onset and peak initial flexor rms EMG for long torque reaction times was 294 ms which decreased to 161 ms for short torque reaction times. The average latency between peak tool spindle torque, just prior to tool shut-off, and peak final rms EMG for long torque reaction times was 97 ms for flexors and 188 ms for extensors, which decreased for short torque reaction times to 47 ms for flexors and 116 ms for extensors. The results suggest that right angle nutrunner torque reaction forces can affect extrinsic hand muscles in the forearm, and hence grip exertions, by way of a reflex response.(ABSTRACT TRUNCATED AT 400 WORDS)