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991.
简要阐述了DDS技术的基本原理,介绍了一种由TMS320VC5509A DSP控制器为核心的任意波形发生器。详细叙述了该波形发生器的硬件设计原理及软件设计方法。本设计具有结构简单、性能稳定、生成波形精度高及可扩展性好等优点。  相似文献   
992.
In a hemodialysis process, the blood that runs through straight channels exchanges substances with the dialysate through a semi-permeable membrane. The waste products, such as urea and creatinine, are therefore removed from the plasma by the membrane. In the analysis of this process, determination of the ultra-filtration profile along the porous membrane surface remains a difficult problem. In this work, an analytical solution to the derivation of such a profile was detailed, and the feasibility of this solution was discussed. The ultra-filtration profile was found to be in a cosine shape.  相似文献   
993.
Along with the development of China's government performance management and budget reform, and also to further improve the management of NSFC, performance ealuation of NSFC is necessary. This test introduces the NSF performance assessment system, and give  相似文献   
994.
A novel hybrid instrument of contact and non-contact measurement with large range is developed, and both measurement systems are based on a Linnik interference microscope and on white-light interference measuring techniques. The ambiguity presented in conventional monochromatic interferometers is not present in the contact and non-contact measurement, and they have a virtually unlimited unambiguous range. For the contact measurement, the vertical measuring range is ±5 mm with a resolution of 1 nm and the horizontal measuring range is ±25 mm in x-range and y-range with a resolution of 1.25 μm; for the non-contact measurement, the vertical measuring range is ~5 mm with a resolution of 1 nm and the horizontal resolution better than 0.5 urn.  相似文献   
995.
In this paper we give an elementary and unified proof of the Hajek-Renyi inequality, and get a general version of this inequality which not only covers the all known results but also derives some new results.  相似文献   
996.
This paper presents a methodology which determines the allocation of power demand among the committed generating units while minimizes number of objectives as well as meets physical and technological system constraints. The procedure considers two decoupled problems based upon the dependency of their goals on either active power or reactive power generation. Both the problems have been solved sequentially to achieve optimal allocation of active and reactive power generation while minimizes operating cost, gaseous pollutants emission objectives and active power transmission loss with consideration of system operating constraints along with generators prohibited operating zones and transmission line flow limits. The active and reactive power line flows are obtained with the help of generalized generation shift distribution factors (GGDF) and generalized Z-bus distribution factors (GZBDF), respectively. First problem is solved in multi-objective framework in which the best weights assigned to objectives are determined while employing weighting method and in second problem, active power loss of the system is minimized subject to system constraints. The validity of the proposed method is demonstrated on 30-bus IEEE power system.  相似文献   
997.
军校校园文化是军校广大师生在日常的教学、学习生活和军事训练等活动中共同创造的一种独具军营特色的人文氛围、精神财富和育人环境,以及承载这些人文氛围、精神财富和育人环境的活动形式和物质形式。军校校园文化通过激发情感认同、加深知识底蕴、从事实践锻炼、树立榜样典型等方式发挥着引领指导价值取向、培养增进多种能力、塑造人格品行、凝聚维系群体、辐射影响社会等功能。建设先进的军校校园文化,能为创办高水平的军事院校提供强大的精神动力和智力保障,对于培养和造就高素质新型军事人才起着十分重要的作用。  相似文献   
998.
实践教学基地是培养应用性专业技术人才的基本支撑条件.在探讨高职院校实践教学基地建设原则的基础上,提出了实践教学基地建设的措施:转变教育观念、制定科学的建设规划、加强校企合作、构建现代企业环境、加大开放力度、提高教师实践教学能力.  相似文献   
999.
We propose a novel vertical Bell Laboratories layered space-time (V-BLAST) based two-way relaying protocol that comprises two user terminals and one multi-antenna demodulate-and-forward (DMF) relay station. We consider the situation when these two user terminals employ different modulation types and investigate its detection techniques. The key feature of the detection techniques is that we quantify decision reliability at the relay station by introducing a so-called normalized correlation coefficient (CORR), rather than having full confidence in demodulation at the relay station. With the assistance of the normalized correlation coefficient, we develop detection methods at both the relay station and user terminals. In particular, we propose a CORR-based ordering algorithm at the relay station which can be applied to detection for general V-BLAST architectures. Simulation results demonstrate the superiority of the CORR-based ordering algorithm over the conventional signal-to-noise based ordering algorithm. Finally, we demonstrate overall error-performance of the V-BLAST-based DMF two-way relaying protocol via simulations.  相似文献   
1000.
Bafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12 (dPC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in dPC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and ΔΨm. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect of Baf on the ΔΨm. Baf induces stochastic flickering of the ΔΨm with a period of 20 ± 10 s. Under conditions of suppressed ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels. Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a number of (patho)physiological conditions induced by Baf.  相似文献   
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