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51.
应用Kalman滤波方法的超短期负荷预报 总被引:11,自引:0,他引:11
几分钟到一小时的超短期负荷预报在电网在线控制中占有重要地位。本文将Kalman滤波方法应用于超短期负荷预测,并在预报过程中引入极大似然估计进行模型未知参数辨识,达到了参数估计过程与预报过程的统一。并给出本算法在几个电网中的实际应用情况及算例分析。 相似文献
52.
本文介绍了测量GIS中隔离开关操作产生的快速暂态过电压的系统构成、准确度分析、使用该测量系统进行现场测量以及仿真计算的结果。 相似文献
53.
L. Quintanilla J. Arias L. Enríquez J. Vicente J. Barbolla D. Vázquez A. Rueda 《Analog Integrated Circuits and Signal Processing》2003,34(3):201-209
A fully differential SC bandpass filter (central frequency, 58 kHz; Q = 15; and voltage gain, 8) based on the switched-opamp approach is designed and implemented in this work. The filter operates from a single 1 V supply voltage and is realized in a 0.35 m CMOS technology. It has been characterized with a sampling frequency of 1 MHz and its power consumption is about 230 W. As a main internal filter component, an appropiate switched opamp was also designed. Its common-mode feedback circuit was implemented by using an error amplifier and sampling of the output common-mode voltage is carried out by applying a DC offset to level shift the common-mode sample. It provides an accurate common-mode output for a wide temperature and supply voltage ranges. 相似文献
54.
指令压缩技术能够克服传统超长指令字(very long instruction word,VLIW)结构的指令高速缓冲(cache)中长指令字密度低的缺陷,使长指令字中的各条指令能紧密地排列在高速缓冲行(cache line)中,但可能导致长指令字分置于两个cache line,使其不能同时参与取指与发射,从而成为处理器的性能瓶颈.受到分置cache line的影响,传统提升循环效率的软件流水方法性能下降.高性能变长指令发射窗的机制能够解决分离指令字带来的取指发射问题,为取指流水线提供高效连续的指令流,特别地,该机制缓存循环的一次迭代,硬件支持循环的软件流水,有效地增强VLIW结构的数字信号处理器(digital signal processor,DSP)的性能.通过搭建时钟精确的处理器仿真模型,并基于DSP/IMG库上进行仿真,结果显示,采用两级指令发射窗机制,平均性能提高约21.89%. 相似文献
55.
Validation simulations are presented for turbulent flow in a staggered tube bank, geometry similar to the lower plenum of a gas-cooled high temperature reactor. Steady 2D RANS results are compared to unsteady 2D RANS results and experiment. The unsteady calculations account for the fact that nonturbulent fluctuations (due to vortex-shedding) are present in the flow. The unsteady computations are shown to predict the mean variables and the total shear stress quite well. Previous workers’ results indicate that 3D simulations are needed to obtain reasonable agreement; present results indicate 2D is sufficient. Best practices are based on requirements for the ASME Journal of Fluids Engineering. 相似文献
56.
S K Agarwal M Bal G D Sharda Mahavir Singh K K Laroia 《Bulletin of Materials Science》1986,8(3):297-305
Doped and undoped polycrystalline silicon films were grown byapcvd and thermal evaporation techniques. The effect of growth and annealing conditions on the crystalline nature of the films
and their properties were studied by electrical, optical, x-ray diffraction andsem techniques. Metal silicides such as TiSi2 and PtSi2 were prepared by co-evaporation technique over polysilicon layers to study their suitability in microelectronic applications.
Some of the properties of polysilicon and silicides are discussed. 相似文献
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In two studies, the authors investigated 2- and 3-year-old children's awareness of the normative structure of conventional games. In the target conditions, an experimenter showed a child how to play a simple rule game. After the child and the experimenter had played for a while, a puppet came (controlled by a 2nd experimenter), asked to join in, and then performed an action that constituted a mistake in the game. In control conditions, the puppet performed the exact same action as in the experimental conditions, but the context was different such that this act did not constitute a mistake. Children's normative responses to the puppet's acts (e.g., protest, critique, or teaching) were scored. Both age groups performed more normative responses in the target than in the control conditions, but the 3-year-olds did so on a more explicit level. These studies demonstrate in a particularly strong way that even very young children have some grasp of the normative structure of conventional activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献