Human-machine interaction force control: using a model-referenced adaptive impedance device to control an index finger exoskeleton

Exoskeleton robots and their control methods have been extensively developed to aid post-stroke rehabilitation. Most of the existing methods using linear controllers are designed for position control and are not suitable for human-machine interaction （HMI） force control, as the interaction system between the human body and exoskeleton is uncertain and nonlinear. We present an approach for HMI force control via model reference adaptive impedance control （MRAIC） to solve this problem in case of index finger exoskeleton control. First, a dynamic HMI model, which is based on a position control inner loop, is for- mulated. Second, the theoretical MRAC framework is implemented in the control system. Then, the adaptive controllers are designed according to the Lyapunov stability theory. To verify the performance of the proposed method, we compare it with a proportional-integral-derivative （PID） method in the time domain with real experiments and in the frequency domain with simu- lations. The results illustrate the effectiveness and robustness of the proposed method in solving the nonlinear HMI force control problem in hand exoskeleton.     

循环流化床煤燃烧/热解多联供工艺中循环灰的密相气力输送

为考察循环流化床煤燃烧/热解多联供工艺中循环热灰的密相输送特性,在实验室建立的密相气力输送装置上分别考察了发料罐内的压力、总松动气量以及特殊位置处的松动气量等对输送固气比的影响。结果表明,在发料罐内压力一定的情况下．固气比随着总松动气量的增加而增大；发料罐内压力的增加也有利于固气比的增大；在发料罐内的压力及总松动气量一定的情况下,随着特殊位置1处松动气量的增加,固气比也随之增大。该密相气力输送方式基本可以满足CFB煤燃烧/热解多联供工艺的要求。     

Studies on the Stability of a La0.8Pr0.2NiAl11O19 Catalyst for Syngas Production by CO2 Reforming of Methane

CO₂ reforming of CH₄ was studied over a magnetoplumbite-type hexaaluminate La_0.8Pr_0.2NiAl₁₁O₁₉ catalyst, which showed very high activity for over 300 h without deactivation at 1023 K. This catalyst showed good resistance to carbon deposition, which in this reaction and in CH₄ decomposition was investigated by means of XPS and TEM. It is suggested that nano-tube-like carbon is an intermediate in this reaction and a spillover of carbon from crystalline Ni onto the hexaaluminate oxide occurred during the reaction.     

我国农业温室气体减排政策适用性研究

农业活动是温室气体的主要排放源之一,近期有关农业温室气体减排的研究已成为我国农业热点问题。针对农业温室气体减排政策在我国的适用性问题,运用IPCC的相关权威标准进行了评价,指出了当前政策工具的不足。提出了通过财政购买建立新的CDM机制来解决我国农业温室气体减排问题的构想。     

一种采用盖尔圆半径修正特征值的信息论判源方法

结合盖尔圆定理与信息论准则提出了一种新的信息论判源准则(MAIC)。对信号采样协方差矩阵进行盖尔圆变换,利用信号协方差矩阵的特征值与对应的盖尔圆半径在区分信号和噪声方面的一致性,用盖尔圆半径修正特征值,并将修正后的特征值及新的罚函数应用于信息论方法得到MAIC判源准则。理论分析表明,由MAIC方法估计得到的目标数目接近真实数目的一致估计,克服了AIC方法在高信噪比下容易出现高估的问题。计算机仿真和湖上试验数据处理结果表明MAIC是一种在高、低信噪比下都能取得良好检测效果的稳健的多目标检测算法。     

Patch nearfield acoustic holography based on the equivalent source method

On the basis of nearfield acoustic holography (NAH) based on the equivalent source method (ESM), patch NAH based on the ESM is proposed. The method overcomes the shortcoming in the conventional NAH that the hologram surface should be larger than the source surface. It need not to discretize the whole source and its measurement need not to cover the whole source. The measurement may be performed over the region of interest, and the reconstruction can be done in the region directly. The method is flexible in applications, stable in computation, and very easy to implement. It has good potential applications in engineering. The numerical simulations show the invalidity of the conventional NAH based on the ESM and prove the validities of the proposed method for reconstructing a partial source and the regularization for reducing the error effect of the pressure measured on the hologram surface. Supported by the National Natural Science Foundation of China (Grant Nos. 10504006 and 50675056) and the Research Fund for the Doctoral Program of Higher Education (Grant No. 20060359003)     

非结构构件地震反应分析及设计方法

对非结构构件的地震反应做了初步的分析,并对非结构构件基于可靠性的结构优化设计和基于性能的结构抗震设计中的一些问题进行了探讨。指出影响非结构构件损坏的主要参数有地震加速度和层间位移角,并由层间位移角量化了部分非结构构件的性能水准指标。     

色彩构成教学模式探讨

传统的教学模式存在很多弊病,阻碍学生的创造性思维的培养.对色彩构成教学模式,从配色能力培养、设计用色、采用高科技手段等方面提出了一系列改革措施.     

智能变电站ICD/CID/SCD模型内容差异检查方法及工具

针对目前智能变电站中ICD/CID之间与SCD中对应IED内容的差异不宜查找的问题,研究了一种多种文档内容差异检查方法及其工具。针对SCD、ICD、CID的语法特点,采用堆栈技术,获得各节点的开始行与结束行号。以两侧节点为完整单位,对节点的标签名和关键属性,进行两侧的交叉检查,找出两侧相同节点,并给出其中非关键属性的顺序错乱、属性值不同、内容不同等多种差异情况。能够对两侧同名节点的开始与结束行进行并列显示,直观同步地对照展示出两个文件中各种差异细节,并能切换到原始文档的相应位置。多个变电站的运行实例验证了该差异检查方法及其工具的有效性。该工具能够提高多个不同文档之间差异检查的准确性和效率。     

海疆N4006/N4010橡胶增塑剂的研制及其在SBS体系中的应用

以中海油绥中36-1环烷基原油为原料,通过常减压蒸馏工艺和高压加氢工艺技术,研制出了符合HG/T 5085-2016化工行业标准的橡胶增塑剂海疆N4006和N4010基础油,油品具有优异的紫外光安定性和热稳定性,适合用作SBS类苯乙烯热塑性弹性体的填充油。研究了两种油品填充的SBS体系的力学性能,耐热性能以及耐紫外光老化性能,并通过红外光谱分析研究了充油体系的老化机理。结果表明充油体系的力学性能良好：拉伸强度 > 10 MPa、断裂伸长率 > 900%,耐光热老化性能优异,热老化后的强度保留率 > 90%,24 h紫外老化后的强度保留率 > 60%。经紫外光辐照试样表面的红外图谱在3 300、1 720和1 170 cm^-1附近出峰,显示老化降解后新增基团主要为羧酸类和脂肪族酯类。热氧老化后充油SBS试样的红外光谱与未老化试样的无差别,表明其优异的耐热氧老化性能。