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991.
Liang Christopher T. H.; Alvarez Alvin N.; Juang Linda P.; Liang Mandy X. 《Canadian Metallurgical Quarterly》2007,54(2):132
On the basis of stress and coping theory, the authors examined coping as a mediator of the relationship between perceptions of racism and racism-related stress with a sample of Asian American college students (N = 336). Results indicated that coping mediated the relationship between racism and racism-related stress differentially by gender. The more that men perceived racism, the more likely they were to use support-seeking coping strategies that were associated with higher levels of racism-related stress. The more that women perceived racism, the more they used active coping strategies that were associated with higher levels of racism-related stress. The findings demonstrate how coping with racism differs for Asian Americans on the basis of gender. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
W. Cavestro 《Automatica》1986,22(6):739-743
This paper deals with small and medium sized firms. Since the late seventies small and medium sized mechanical engineering firms in France have resorted increasingly to new technologies, and in particular to numerical control. Numerical control has introduced major changes in work organization. On the one hand it tends to reinforce the role of methods of production engineering whatever the type of numerical control may be. Programming is seldom left to the machine operators, except in the case of straightforward machining operations or in machining shops with a strong tradition of highly skilled or artisan labour. Numerical control, on the other hand, does provide more opportunity for collaboration between the workshop and the production engineers. On a workshop level it introduces a more mobile division of labour between programmers, machine setters and operators, which covers everything from the start-up of programs to the supervision of maching operations. The operator may therefore acquire new skills, but this is only possible if there are open-ended training systems available to facilitate the transmission of know-how from the programmers to the machine setters and from the machine setters to the operators, and vice versa. Small and medium sized firms would appear to have a special role to play in developing skills. 相似文献
994.
Marc Bodson Shankar SastryBrian D. O. Anderson Iven Mareels Robert R. Bitmead 《Systems & Control Letters》1986,7(3)
The paper presents nonlinear averaging theorems for two-time scale systems, where the dynamics of the fast system are allowed to vary with the slow system. The results are applied to the Narendra-Valavani adaptive control algorithm, and estimates of the parameter convergence rates are obtained which do not rely on a linearization of the system around the equilibrium, and therefore are valid in a larger region in the parameter space. 相似文献
995.
996.
神经网络控制系统的研究与展望 总被引:15,自引:2,他引:15
本文综述了近年来神经网络应用于控制领域的研究概况,并对其存在的问题和发展趋势作了讨论。 相似文献
997.
对仅有方位量测的被动目标定位中观测平台最优机动轨迹问题进行了探讨.在最大化Fisher信息阵 (FIM)行列式指标下给出了当前时刻一种新的机动控制策略,从理论上证明了最优机动轨线有且仅有2支,并给出了最优机动策略和最优机动轨线方程;它的特点是对任意时刻均为最优,而不仅仅在观测时间的末端,几何直观描述了机动控制序列的可执行性;与最大化方位变化率下观测平台最优机动轨线相比较,本文的机动策略兼顾了距离和方位2个因素的影响,可看成是对距离信息和方位信息之间的折中.数字仿真表明,与传统方法比较,提出的新机动策略能获得更大的信息. 相似文献
998.
Due to the complexity of modern industrial systems, a conventional automation system is not capable of providing sufficient information management and high-level intelligent approaches, as achieving these functionalities requires the support of comprehensive data management and coordination between system devices and heterogenous information. This paper proposes the concept of e-Automation, in which computer networking and distributed intelligence agent technologies are applied to industrial automation systems, and presents a hardware and software architecture that implements this concept. An open infrastructure based on multi-agent systems is employed in the proposed architecture of e-Automation, which aims to allow the implementation of diverse tasks and to permit greater configurability than can be obtained from a traditional system. To evaluate our proposed e-Automation concept, this paper presents a case study of substation information management which adopts the proposed e-Automation architecture in power system domain. 相似文献
999.
兆瓦级同步风力发电机变桨距控制策略研究 总被引:2,自引:2,他引:2
变桨距风力发电机已成为风力发电机组的主要研究和发展方向,结合长星集团同步风力发电机组,对变桨距控制技术进行了研究,在额定风速以下时实行变速运行,控制发电机的励磁电流从而控制发电机的转速,使得风力机转速能够跟随风速变化,保持最佳叶尖速比使系统获得最大的风能利用系数;额定风速以上时,采用PID控制算法控制桨距角,使发电机输出功率恒定,并提出了实现方法;通过仿真工具进行计算机仿真,验证了本方法的有效性。 相似文献
1000.
Information is the core of Air traffic con-trol system (ATCS).In this paper,objective information theory is extended to depict,model and measure the information exemplified in ATCS.The sextuple model is presented with information ontology,state occurrence time,state set,carrier,reflection time,and reflection set.The metric system is given to quantitively measure the information with extensity,detailedness,continuity,richness,containability,delay,pervasiveness,authenticity,and adaptability.The results show that the proposed method is potential to find out actual indexes in ATCS for flight safety. 相似文献