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71.
Vladimir Z. Kresin Stuart A. Wolf Yu. N. Ovchinnikov 《Journal of Superconductivity》1996,9(3):329-333
The value of the critical temperature of the cuprates correlates with the doping level and is affected by the interplay of two competing factors: (1) the increase in carrier concentration, and (2) the pair-breaking effect of magnetic impurities. An analysis of the temperature dependence of the critical field leads to the conclusion that magnetic impurities are present even in a sample with the maximum observed value ofT
c.A new parameter, intrinsicT
c (T
cintr), which is its value in the absence of magnetic impurities, is introduced. The maximum value ofT
cintr, which corresponds to the maximum doping level, appears to be similar for different cuprates and to be equal to 160–170 K. This is the upper limit ofT
c in the cuprates. 相似文献
72.
73.
74.
HUANG Yi CHEN ZongJi & WEI Chen National Key Laboratory of Science Technology on Integrated Control Technology School of Automation Science Electric Engineering Beihang University Beijing China 《中国科学:信息科学(英文版)》2010,(2):258-270
To improve the consistency of estimation result, a least-trace extended set-membership filter (LTESMF) is presented for a class of nonlinear stochastic systems, which has linear output and unknown- but-bounded noise. Feedback technique is used instead of the intersection of ellipsoid-sets in the measurement update. The feedback parameter is optimized in order to minimize the trace of error bounded ellipsoid’s envelop matrix. A new stability analysis method was developed to prove the stochastic system’s stab... 相似文献
75.
Yoshifumi Morita Norihiro Toya Ryosuke Takeichi Hitomi Hattori Hirofumi Tanabe Yoshiaki Takagi 《Advanced Robotics》2016,30(21):1406-1414
We developed a new training system, called ‘UR-System 2’, for the recovery of motor function of a plegic upper limb after stroke. UR-System 2, which was redesigned based on knowledge gained from clinical tests using UR-System 1, was newly equipped with a function for testing the motor function of patients, such as isolated movement. In order to verify the effectiveness of UR-System 2, we conducted the following procedures: we verified the safety of training in healthy persons; we gathered standard data on pronation and supination of healthy forearms during tests; and, we verified that the test function was effective in evaluating the recovery effect of isolated movement in two hemiplegic patients. 相似文献
76.
77.
Output feedback regulation of upper triangular nonlinear systems with uncertain time‐varying delays in states and input
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In this paper, an output feedback controller is studied to regulate a class of upper triangular nonlinear systems with uncertain time‐varying delays. The key features of our considered system are that there are uncertain time‐varying delays in both states and input and the high‐order nonlinearity is in a more relaxed form over the previous results. Theoretical analysis and numerical example are presented to show the benefits of our controller. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
78.
RSKNN算法是K近邻算法的一种改进算法,该算法基于变精度粗糙集理论,能在保证一定分类精度的前提下,有效地降低分类样本的计算量,并且提高计算效率和分类精度.由于RSKNN算法对属性的依赖度较高,在分类时容易受到伪近邻的影响,导致RSKNN算法的分类精度受到一定程度的影响.针对存在问题,本文提出一种新颖的基于RSKNN算法的改进算法SMwRSKNN,该算法在RSKNN算法的基础上引入类别子空间的思想,以降低冗余属性和伪近邻对分类的影响.在UCI公共数据集上的实验结果表明,SMwRSKNN算法比RSKNN算法具有更高的分类精度. 相似文献
79.
电缆温度监测是一些大中型企业经常面临的问题。详细介绍了利用计算机、单片机构成的电缆接头温度自动监测系统。通过该系统可及时获得电缆温度变化情况 ,为安全生产提供保障 相似文献
80.
The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological effects, and so on. However, indices for evaluating the modernization of water conservancy project management are usually unobtainable in practical applications. Conducting appropriate extension of the classical rough set theory and then applying it to an incomplete information system are the key to the application of the rough set theory Based on analysis of some extended rough set models in incomplete information systems, a rough set model based on the θ-improved limited tolerance relation is put forward. At the same time, upper approximation and lower approximation are defined under this improved relation. According to the evaluation index system and management practices, the threshold for θ is defined. An example study indicates the practicability and maneuverability of the model. 相似文献