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331.
This paper describes a method for scheduling the events of a switched system to achieve an optimal performance. The approach has guarantees on convergence and computational complexity that parallel derivative-based iterative optimization but in the infinite dimensional, integer constrained setting of mode scheduling. In comparison to methods relying on mixed integer programming, the presented approach does not require a priori discretizations of time or state. Furthermore, in comparison to embedding and relaxation methods, every iteration of the algorithm returns a dynamically feasible solution. A large class of problems call for optimal mode scheduling. This paper considers a vehicle tracking problem and a high dimensional multimachine power network synchronization problem. For the power network example, both single horizon and receding horizon approaches prevent instability of the network, and the receding horizon approach does so at near real-time speeds on a single processor. 相似文献
332.
Jér?ome?DegallaixEmail author Bram?Slagmolen Chunnong?Zhao Li?Ju David?Blair 《General Relativity and Gravitation》2005,37(9):1581-1589
Thermal lensing is becoming recognized as one of the dominant obstacles to the second generation of laser interferometric
gravitational wave detectors. Very high optical power is required to circulate in the interferometer to reach the sensitivity
goal, creating strong thermal induced wavefront distortion. These effects will be studied at the High Optical Power Test Facility
in Gingin, Western Australia. In this paper, we present simulation results for the first test planned for the middle of 2004.
This experiment will produce 5 kW of optical power circulating inside a Fabry–Perot cavity and will demonstrate large thermal
lensing effects.
Two compensation methods were investigated to offset the negative effect of thermal lensing on the cavity: a compensation
plate within the arm cavity and adaptive laser mode matching. Advantages and disadvantages of both systems are discussed. 相似文献
333.
Dines Bjørner 《BIT Numerical Mathematics》1970,10(2):125-144
Flow-mode or stream-processing digital systems have been proposed in which code, control and data are constantly moving so that multiple instructions are processed concurrently. We show the design of a flow-mode cellular array processor which can perform a number of two's complement fixed-point arithmetic operations. These operations are: three operand addition and/or subtraction, two operand multiplication and vector inner-product. Operand sizes are: 2N bit for addition and subtraction operands, andN bit for multiplication operands. Results are 2N bit. The network can simultaneously operate on 4N+2 datasets with any mix of the above operations being handled. The processor is based on the use of asynchronous cellular arrays. Given a continued flow of input datasets, the effective computation time is worst-case propagation time within one cell. A typical cell contains a 1-bit position 3-input full adder with associated input data storage. Thus the effective computation time is independent of the operand bit length. 相似文献
334.
本文用数理统计中的x~2—检验方法以及中位数、众数为了具,从学生的考试成绩对教学质量进行量比评估,以提高教学管理水平。 相似文献
335.
336.
生产实习是所有工科高校中培养理论联系实践的高素质人才的重要环节,而生产实习的模式将直接影响学生对理论知识的理解及其理论与实际相结合的认识.针对目前本专业在生产实习过程中存在问题的分析和对国内外多所高校实习模式的调研,详细地探讨了与本专业相关的生产实习模式及其改进的方法,除了需要进一步加强校外实习,还提出了校外实习与校内实习相结合、成立专职教师队伍、引入工程类"project"项目等改革方案,根据学生对专业理论知识掌握及自身兴趣的不同,提出了分层次、分类别实习的模式,由此进一步提高学生的工程实践能力,增强其创新意识. 相似文献
337.
探讨普通物理教学中存在的问题,就大学普通物理实验课程的设置、教学模式及考核方式,提出几点看法及解决方案,为大学普通物理实验的改革提供参考。 相似文献
338.
We propose an alternative model based on mode conversion for computing axial and transverse intensity field distributions of apertured systems. We then develop a new method for the integration of oscillating functions that derive from the model. The integration technique we developed is efficient, very fast and would be useful in many other fields of physics. 相似文献
339.
在单个波长通道的传输速率高于10Gbit/s的超高速光纤传输系统中,偏振模色散极大地限制了整个通信系统的通信容量,必须加以控制和补偿。先对偏振模色散的产生机理、统计分布规律进行了分析、讨论,接着介绍了在光纤线路中测量偏振模色散的后向散射光测试法及其测量原理,并从琼斯矩阵(偏振态传输函数矩阵)出发,通过分析其泰勒展开式,分别推导出可补偿一阶和二阶偏振模色散的均衡器所需满足的条件,并给出了原理框图。 相似文献
340.
Byeong Ha Lee Young-Jae Kim Youngjoo Chung Won-Taek Han Un-Chul Paek 《Fiber and Integrated Optics》2001,20(5):443-455
A novel method based on fiber gratings for measuring the effective indices of fiber modes is proposed. The effective index difference between the core mode and a cladding mode was obtained by analyzing the interference fringe of a pair of cascaded long-period fiber gratings. In order to extract the core mode index from the measured index difference, an index matching oil immersion method is proposed. By analyzing the interaction between the cladding mode and the oil applied on the cladding surface, the mode order and the effective index of the involved cladding mode might be calculated. Experimental results about the interference fringe shifts induced by the oil index and the oil-applied length are also presented. 相似文献