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41.
In this paper, the special construction of a parallel robot, called spatial servopneumatic multi-axis test facility, will be discussed. The investigations include the following aspects: (i) the laboratory set-up of the robot, (ii) various results obtained in laboratory experiments, taking into account quite different control algorithms and command-input signals, (iii) a comparison of the laboratory experiments with the computer simulations of Part I of this paper, and ({vi}) a quality check of the results compared with the cost of the different controller realizations. The results of both the computer simulations and the laboratory experiments show: (i) The dynamic behavior of the parallel structure can be tremendously improved by using sophisticated nonlinear control algorithms. (ii) This improvement has to be paid by a drastically increased amount of work for deriving the model equations and control algorithms, and by augmented hardware cost of the sensing elements and controller electronics. (iii) Carefully developed model equations and identified model parameters provide theoretical models of the complex parallel structure that are very close to reality. This enables the design engineer to systematically investigate constructive alternatives of the design parameters, sensor and actuator concepts, and control strategies of the MAP prior to their hardware realization.This work has been supported by the German Science Foundation (DFG) under Contract No. Ha 1666/6-3.  相似文献   
42.
By using a novel free-flying, rotating, optical bench aboard the International Space Station (ISS) as the basis for a measurement of differential acceleration between two gravitating bodies, in principle the Newtonian inverse-square law and the constant of gravitation, G, can be determined at the parts in 106 level.  相似文献   
43.
In the present paper, some new almost fixed point theorems and fixed point theorems for lower semicontinuous type multivalued mappings are obtained in metrizable H-spaces.  相似文献   
44.
弱拓扑和强可容许拓扑之间的一个关系   总被引:2,自引:0,他引:2  
孙立民 《数学杂志》2003,23(2):141-145
本文对局部凸空间X及其对偶X′,建立了弱拓扑σ(X,X′)和强拓扑β(X,X′)之间的一个新关系,改进了有关(X,X′)--可容许拓扑全体上的不变性结果。  相似文献   
45.
We develop a method of randomizing units to treatments that relies on subjective judgement or on possible coarse modeling to produce restrictions on the randomization. The procedure thus fits within the general framework of ranked set sampling. However, instead of selecting a single unit from each set for full measurement, all units within a set are used. The units within a set are assigned to different treatments. Such an assignment translates the positive dependence among units within a set into a reduction in variation of contrasting features of the treatments. A test for treatment versus control comparison, with controlled familywise error rate, is developed along with the associated confidence intervals. The new procedure is shown to be superior to corresponding procedures based on completely randomized or ranked set sample designs. The superiority appears both in asymptotic relative efficiency and in power for finite sample sizes. Importantly, this test does not rely on perfect rankings; rather, the information in the data on the quality of rankings is exploited to maintain the level of the test when rankings are imperfect. The asymptotic relative efficiency of the test is not affected by estimation of the quality of rankings, and the finite sample performance is only mildly affected.  相似文献   
46.
对弱相对论性电子束驱动的回旋激射(maser)不稳定性的一般理论作了详细讨论.对在获得增长率实用表达式过程中若干解析表达式的推导与细节做了仔细的补充讨论和说明,还增加了增长率的近似表达式,并由此得到了回旋激射不稳定性主要特征的解析分析以及与精确计算的比较,使整个理论有一个完整的描述.侧重解析讨论,也提供了部分一般性的数值计算结果. 关键词: 回旋激射不稳定性 弱相对论性电子束 增长率  相似文献   
47.
We consider the problem of minimizing an SC1 function subject to inequality constraints. We propose a local algorithm whose distinguishing features are that: (a) a fast convergence rate is achieved under reasonable assumptions that do not include strict complementarity at the solution; (b) the solution of only linear systems is required at each iteration; (c) all the points generated are feasible. After analyzing a basic Newton algorithm, we propose some variants aimed at reducing the computational costs and, in particular, we consider a quasi-Newton version of the algorithm.  相似文献   
48.
声诱饵仿真试验系统   总被引:1,自引:0,他引:1       下载免费PDF全文
苑秉成  陈喜  周徐昌  张振山 《应用声学》2003,22(4):31-34,39
文章介绍了声诱饵仿真试验系统中的有关问题,包括:系统的组成、工作原理、对接装置结构等。建立了对接装置声耦合状态下的数学模型,对近场声压分布进行了仿真计算,得出了匹配材料厚度、发射和接收换能器的选取原则。  相似文献   
49.
Some results on underground structures obtained by Kazakh mechanicians are reviewed. The review covers a period of the last forty years. Also results on the mechanics of special objects are discussed.Translated from Prikladnaya Mekhanika, Vol. 40, No. 10, pp. 3–36, October 2004.  相似文献   
50.
本文对三层BP神经网络中带有惩罚项的在线梯度学习算法的收敛性问题进行了研究,在网络训练每一轮开始执行之前,对训练样本随机进行重排,以使网络学习更容易跳出局部极小,文中给出了误差函数的单调性定理以及该算法的弱收敛和强收敛性定理。  相似文献   
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