Push/Pull和CONWIP/Pull生产控制模式对比分析

针对制造企业如何有效地进行生产控制的问题,对Push/Pull、CONWIP、CONWIP/Pull生产控制模式作了详细介绍,对比分析了Push/Pull、CONWIP/Pull两种混合生产控制,对混合生产控制方法做出了研究展望.     

近终形薄带连铸工艺技术比较

近终形薄带连铸是钢铁工业简化工序，节能降耗，降低成本最具有竞争能力的一项重大新工艺技术，本文报导了世界各先进工业国近年来开展研究的最新成果，分析比较了诸多机型的优缺点，并提出了突破工艺技术的技术关键和建议。     

社会比较对薪酬不公平感的心理作用机制

运用社会比较理论,分析了在组织内部影响薪酬不公平感的社会比较类型与评判内容;利用对比效应与同化效应,解释了薪酬不公平感的形成。在此基础上,探讨了人力资源管理中减少或克服人际攀比带来不良影响的途径。     

Increasing testing productivity and software quality: A comparison of software testing methodologies within NASA

Pressure to compress the development life cycle and reduce the duration and resources committed to testing lead to experimentation in testing at the NASA Goddard Space Flight Centerís Software Engineering Laboratory. This study investigates the trend to reduce developer testing and increasingly rely upon inspection techniques and independent functional testing to shorten the development life cycle, improve testing productivity, and improve software quality.An approach is developed to conduct this comparison. In particular, the problem faced by software researchers, having a comprehensive characterization of software projects so similar types may be identified for comparative studies, is addressed using expert opinion.     

Stability of impulsive stochastic functional differential systems in terms of two measures via comparison approach

Comparison principles for general impulsive stochastic functional differential systems are established.Employing the comparison principles and the theory of differential inequalities,stability and instability,involving two measures,of impulsive stochastic functional differential systems are investigated.Several stability and instability criteria are obtained,and two examples are also given to illustrate our results.     

IRS-P6 LISS-3和Landsat-5 TM两种多光谱传感器影像数据的对比分析

随着载有各种新型传感器的卫星相继发射升空,不同传感器之间的相互比较成了一个研究热点。首先从传感器的轨道特征、光谱范围等方面对IRS-P6 LISS-3和Landsat-5 TM进行了机理方面的对比分析,选取3对同日过空的遥感影像,研究了IRS-P6 LISS-3和Landsat-5 TM遥感数据在可见光-近红外、短红外各对应光谱波段之间的关系,建立TM和LISS-3各波段之间的相互转换公式,与Chander等提出的转换公式进行对比分析。结果表明:实际TM和模拟TM多光谱数据之间具有较强的相关关系,决定系数R²均大于0.97;模拟TM与实际TM的水体指数(MNDWI)和归一化植被指数(NDVI)空间散点分布和实际LISS-3与实际TM的空间散点分布相比,具有更强的相关关系,其决定系数R²有一定提高,散点分布趋于对称。因此,所求的关系转换方程具有较高的精度和有效性,效果优于Chander等提出的转换公式。     

预制桥面板 ＵＨＰＣ湿接缝的界面受力性能研究

为确定合理的界面间约束与接触关系,采用ＡＢＡＱＵＳ中3种不同的约束与接触关系基于现有试验试件进行模拟,将数值分析结果与试验结果与进行对比分析。研究表明:采用内聚力模型的有限元模型破坏形态与试验结果较为一致,绑定约束次之,而采用接触摩擦模型的有限元模拟结果与试验差别最大;以试验开裂荷载与极限荷载为分析对象,绑定约束与内聚力模型的数值分析结果与试验吻合较好,而接触摩擦模型的数值分析结果与试验差异较大;与绑定约束模型相比,内聚力模型能够较好地模拟试件界面的损伤。因此,当采用ＡＢＡＱＵＳ进行预制桥面板与ＵＨＰＣ湿接缝的界面受力的有限元分析时,宜采用内聚力模型或绑定约束模型,不宜采用接触摩擦模型。     

Safe and intuitive manual guidance of a robot manipulator using adaptive admittance control towards robot agility

Key areas of robot agility include methods that increase capability and flexibility of industrial robots and facilitate robot re-tasking. Manual guidance can achieve robot agility effectively, provided that a safe and smooth interaction is guaranteed when the user exerts an external force on the end effector. We approach this by designing an adaptive admittance law that can adjust its parameters to modify the robot compliance in critical areas of the workspace, such as near and on configuration singularities, joint limits, and workspace limits, for a smooth and safe operation. Experimental validation was done with two tests: a constraint activation test and a 3D shape tracing task. In the first one, we validate the proper response to constraints and in the second one, we compare the proposed approach with different admittance parameter tuning strategies using a drawing task where the user is asked to guide the robot to trace a 3D profile with an accuracy or speed directive and evaluate performance considering path length error and execution time as metrics, and a questionnaire for user perception. Results show that appropriate response to individual and simultaneous activation of the aforementioned constraints for a safe and intuitive manual guidance interaction is achieved and that the proposed parameter tuning strategy has better performance in terms of accuracy, execution time, and subjective evaluation of users.     

一类线性时变群体系统稳定性的代数判据

针对在判断群体系统的稳定性时没有一般的方法和程序构造Lyapunov函数这个难点,利用矩阵范数,孤立子系统的矩阵指数函数与比较原理提出了一类线性时变群体系统平凡解一致稳定,所有解一致有界的充分条件。方便此类群体系统的稳定性分析,为研究其他群体系统稳定性的代数判据提供了理论基础。可以在此基础上,进一步研究一类非线性群体系统稳定性的代数判据。同时,还给出了具体算例,说明所提方法的正确性。此代数判据应用简便,灵活,适于实际应用。     

Randomized range-maxima in nearly-constant parallel time

Given an array ofn input numbers, therange-maxima problem is that of preprocessing the data so that queries of the type what is the maximum value in subarray [i..j] can be answered quickly using one processor. We present a randomized preprocessing algorithm that runs inO(log^* n) time with high probability, using an optimal number of processors on a CRCW PRAM; each query can be processed in constant time by one processor. We also present a randomized algorithm for a parallel comparison model. Using an optimal number of processors, the preprocessing algorithm runs inO( (n)) time with high probability; each query can be processed inO ( (n)) time by one processor. (As is standard, (n) is the inverse of Ackermann function.) A constant time query can be achieved by some slowdown in the performance of the preprocessing stage.