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OALib Journal期刊

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Recursive Implementation of Stack Filtering
堆栈滤波的递归实现

ZHANG Wei,<br>
中国图象图形学报 , 2000,
Abstract: As a kind of nonlinear filters, stack filters can suppress impulse noise effectively, and keep edges and details at the same time. Those have two important properties: the threshold decomposition and the stack properties, which ensure that the filtering process go on in binary field parallelly. The optimal stack filters under mean absolute error (MAE) criterion can be developed with least mean absolute error (LMA) algorithm. The filters developed directly are non recursive filters. Based on the above, the recursive implementation approach of optimal stack filters under MAE criterion are advanced. Two approaches are used: direct recursive approach and optimal recursive approach, the latter resolve the matching between filter and input signals. The result of simulation with computer software illustrate that, the characteristics of noises removing of recursive stack filters are superior to that of non recursive filters, and the characteristics of edges and details preserving of the former are similar to the latter. So we can conclude that the advanced recursive approaches improve the function of the stack filters, which is meaningful to the advanced study for theory of stack filtering.
A NEW SPECIES OF GENUS PSEUDOCLATHRUS
假笼头菌属一新种

ZHOU WEI,<br>周,克勤
菌物学报 , 1987,
Abstract: A new species of the genus Pseudoclathrus collected from Leigong Mountains of Guizhou Province is described as Pseudoclathrus leigongshanensis W.Zhou et Zhang sp.nov.English and Latin diagnoses are given for the new species.And a Chinese summary is also given. Holotypes of the new species are deposited in the Mycological Herbarium of Institute of Bio- logy,Academia Guizhou.(Kweichow),China.
NUMERICAL SIMULATION STUDY OF LASER-DRIVEN SHOCKWAVE PROPAGATION IN PLANAR Al FOIL TARGETS
冲击波在铝靶中传播的数值模拟研究

WANG WEI,ZHANG JIE,VKSENECHA,<br>王,
物理学报 , 2001,
Abstract: The-numerical simulation study of an experimental result of laser-driven shock wave propagation in a planar aluminum foil target is performed using a one-dimensional radiation hydrodynamic code MULTI. The effect of spatial mesh size on numerical simulation resulits is found to be significant and optimum mesh size is obtained.-Series of simulations are performed using different sets of laser absorption coefficients and the most appropriate laser absorption coefficients value for two laser intensity values used in the experiment is obtained .The results suggest that shock velocities and peak shock pressures are in good agreement with the experimental results.
DETECTION OF DIFFERENTIAL ITEM FUNCTIONING IN ACHINESE VOCABULARY TEST
汉语词汇测验中的项目功能差异初探

Cao Yiwei,<br>曹亦,厚粲
心理学报 , 1999,
Abstract: This study used two different differential item functioning (DIF) detection methodsin a Chinese vocabulary test. The DIF was analyzed for female--male and suburbsmetropolis groups.The sample consisted of 1409 grade 9 juniors from Beijing suburbsand Shenzhen metropolis.The 7 items were detected triform DIF in the results offemale-male group, while 5 items were uniform DIF and 2 items were nonuniformDIF in the suburbs-metropolis groups.Several plausible factors for DIF.were discussed.
How to Improve Ways in Evaluating Quality of Sci-tech Journals
科技期刊评价方法的改进

ZHANG Wei,XIAO Hong,<br>,肖红
中国科技期刊研究 , 2005,
Abstract: 简述和分析我国科技期刊主要评价方法及评价指标体系的特点,指出现有科技期刊评估方法及评价指标的不足:针对学术类与技术类期刊各自不同的特点,提出了“二次分类”的建议,并引入了“下载量”这一网络环境下新的评价指标。
Determination of C_1-C_5 Composition of Liquefied Petroleum Gas by Capillary Gas Chromatography
毛细管气相色谱法测定液化石油气中C_1~C_5组分的方法研究

Zhang Weijun,Yi Hong,<br>,易红
色谱 , 1999,
Abstract: In this paper, thirteen C1-C5 hydrocarbons in liquefied petroleum gas were separated and determined by using capillary gas chromatography. The cloumn used was 50 m x 0.53 mm i.d. HP PLOT-Al2O3. A standard mixture of known composition was used for the determination of correction factots and the corrected area mormalization was used for quantification. The relative standard deviations (n = 5) were 0.39%-5.4%. Ethane, ethylene and butene were separated to baseline.
Luminescence Characteristics of a Blue-Green Emission Thin Film Electroluminescence Device Based on a ZnSe Emitting Layer
ZnSe为发光层的蓝绿光薄膜电致发光器件的发光性能

Jiang Weiwei,Zhao Suling,Zhang Fujun,Xu Zheng,<br>姜,赵谡玲,福俊,徐征
半导体学报 , 2008,
Abstract: A device with a ITO/SiO2/ZnSe/SiO2/Al structure was deposited by electron beam evaporation.Blue-green electroluminescence of ZnSe film,which does not appear in the traditional sandwich structure,was observed.The dependence of emission on applied voltage and frequency were studied in detail.The luminescence mechanism of the device was discussed.It is thought that original electrons are accelerated in the SiO2 layer where they obtain energy and bombard the ZnSe molecules.The electrons in the valence band of the ZnSe are excited to the conduction band.The excited electrons transit back to the valance band or the defect energy level and give emission.This mechanism is called solid state cathodoluminescence because the electrons accelerate in the solid but not in the vacuum.This phenomenon can provide a new way to realize blue inorganic electroluminescence.
Photovoltaic maximum power point tracking system
光伏发电最大功率跟踪系统的研究

HE Wei-wei,YANG Jin-ming,ZHANG Miao,<br>何,杨金明,
控制理论与应用 , 2008,
Abstract: A new adaptive fuzzy controlling scheme is proposed for the photovoltaic maximum power point tracking. The theory proves that the algorithm of on-line self-adjusting used to alter the fuzzy rule bases makes the photovoltaic system stable globally. Based on such a scheme, good dynamic function and high robustness are achieved. The performance of the system is evaluated by the simulation conducted with Simulink tools in MATLAB7.0 and satisfied results are obtained.
存在纯粹的法理学吗?

中外法学 , 2000,
Abstract:
社群环境下用户协同信息行为研究述评

中国图书馆学报 , 2010,
Abstract: 随着协同技术的发展以及Web2.0群体交互性虚拟社群的出现,用户协同信息行为已经逐渐成为新的研究热点。协同信息行为的类型主要包括:协同信息查寻与检索、计算机支持的社群信息交流、协同内容创作和协同信息质量控制。协同信息查寻与检索的研究成果较为丰富,而协同内容创作,尤其是协同信息质量控制的研究相对较少。协同理论也是协同信息行为研究的一个必要组成部分,目前尚缺乏对社群用户在协同系统环境下的信息活动及其情感、认知的综合研究,缺乏对异步、异地发生的用户协同信息行为的研究。此外,如何设计和构建群体交互式虚拟社群环境,以更好地提升用户协同信息活动的效果,这些都将成为新的研究课题。图1。参考文献64。
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