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Chinese Physics B 2013年第8期22卷 404-409页

作者：焦重庆朱弘钊 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

The cavity-mode resonance effect could result in significant degradation of the shielding effectiveness （SE） of a shielding enclosure around its resonance frequencies. In this paper, the influence of coated wall loss on the suppression of the resonance effect is investigated. For this purpose, an equivalent circuit model is employed to analyze the SE of an apertured rectangular cavity coated with an inside layer of resistive material. The model is developed by extending Robinson＇s equivalent circuit model through incorporating the effect of the wall loss into both the propagation constant and the characteristic impedance of the waveguide. Calculation results show that the wall loss could lead to great improvement on the SE for frequencies near the resonance but almost no effect on the SE for frequencies far away from the resonance.

关键词： electromagnetic shielding rectangular cavity wall losses resonance effect

NUMERICAL STUDY ON SALINITY STRATIFICATION IN THE OUJIANG RIVER ESTUARY

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Journal of Hydrodynamics 2009年第6期21卷 835-842页

作者： JIANG Heng-zhi SHEN Yong-ming WANG Shou-dong State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Transport Planning and Research Institute Beijing 100048 China

The variations of current, salt intrusion and vertical stratification under different conditions of river flow and wind in the Oujiang River Estuary （ORE） were investigated in this article using the Environmental Fluid Dynamics Code （EFDC）. The model was verified against water level variation, velocity, and salinity variations in June 2005. The simulation results agreed well with measured data. Six sensitivity tests were conducted for different conditions of river flow and wind specified in the model. Model results show that salinity intrudes further upstream under scenarios with low flow and downriver local wind conditions. In contrast, the responses of salinity stratification to different environmental forcing functions were different in different portions of the estuary. Salinity stratification was enhanced under high flow condition. Model results also show that wind is not crucial to the salt intrusion and salinity stratification in the ORE.

关键词： salinity stratification wind river discharge Oujiang River Estuary(ORE)

LDFF,the large molecular weight DNA fragmentation factor,is responsible for the large molecular weight DNA degradation during apoptosis in Xenopus egg extracts

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Cell Research 2004年第2期14卷 134-140页

作者： Zhi Gang LU, Chuan Mao ZHANG~*, Zhong He ZHAI~* Department of Cell Biology and Genetics, College of Life Sciences, Peking university, beijing 100871, china. Department of Cell Biology and Genetics College of Life Sciences Peking University Beijing 100871 China.

DNA degradation is a biochemical hallmark in apoptosis. It has been demonstrated in many cell types that there are two stages of DNA fragmentation during the apoptotic execution. In the early stage, chromatin DNA is cut into large molecular weight DNA fragments, although the responsible nuclease(s) has not been recognized. In the late stage, the chromatin DNA is cleaved further into short oligonucleosomal fragments by a well-characterized nuclease in apoptosis, the caspase-activated DNase (CAD/DFF40). In this study, we demonstrate that large molecular weight DNA fragmentation also occurs in Xenopus egg extracts in apoptosis. We show that the large molecular weight DNA fragmentation factor (LDFF) is not the Xenopus CAD homolog XCAD. LDFF is activated by caspase-3. The large molecular weight DNA fragmentation activity of LDFF is Mg2+-dependent and Ca2+-independent, can occur in both acidic and neutral pH conditions and can tolerate 45℃ treatment. These results indicate that LDFF in Xenopus egg extr

关键词： apoptosis caspase-activated DNase (CAD) large molecular weight DNA fragmentation factor (LDFF).

SOME REMARKs ON OVERCONVERGENCE OF HERMITE INTERPOLATING POLYNOMIALS

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Analysis in Theory and Applications 1994年第3期10卷 79-92页

作者： Lou Yuanren Peking university, china 1. Department of Mathematics Peking University 100871 Beijing P.R. China

In this paper. a quantitative estimate for Hermite interpolant to function ψ(z)=(z^m-β~m)~l on the ze- ros of (z^n-α~n)~r is obtained Using this estimate. a rather wide exiension of the theorem of Walsh is proved a... 详细信息

关键词： SOME REMARKs ON OVERCONVERGENCE OF HERMITE INTERPOLATING POLYNOMIALS

Research progress of the NSFC Major Research Plan “Dynamic Disaster Evolution of Major Engineering Structures”

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Science china(Technological Sciences) 2010年第2期53卷 592-594页

作者： RU JiPing1, LI DaPeng1, LI ZhongXian2 1 Department of Engineering & Materials Science, NSFC, beijing 100085, china 2 School of Civil Engineering, Tianjin university, Tianjin 300072, china 1. Department of Engineering & Materials Science NSFC Beijing 100085 China2. School of Civil Engineering Tianjin University Tianjin 300072 China

The NSFC Major Research Plan aims to conduct researches at the international research frontiers on modeling of strong earthquake ground motions and strong wind or typhoon fields, and investigating the damage and failure evolution process of the major engineering structures under dynamic actions, focusing on the following two key scientific problems: (1) characteristics and laws of strong earthquake ground motions and strong wind or typhoon fields, and (2) process and mechanism of dynamic disaster evolution of the major engineering structures. For these goals, the research work is targeted at (1) modeling and predicting of strong earthquake ground motion and strong wind or typhoon fields, (2) identifying critical parameters influencing the dynamic disaster evolution of the major engineering structures, (3) analyzing the whole dynamic disaster evolution process of the major engineering structures, and (4) integration and verification of simulation systems for dynamic disaster evolution of the major engineering structures.

关键词： major engineering structures dynamic disaster evolution research progress

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 Key Laboratory of petroleum resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china 2 Department of Geology, Northwest university, Xi’an 710069, china 1. Key Laboratory of petroleum resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

Association Rule Discovery and Its Applications

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Journal of china university of Geosciences 2001年第3期12卷 279-282页

作者： Cai Zhihua Wu Xincaifaculty of information Engineering, china university of Geosciences, Wuhan 430074 faculty of information Engineering China University of Geosciences Wuhan 430074

Data mining, i.e., mining knowledge from large amounts of data, is a demanding field since huge amounts of data have been collected in various applications. The collected data far exceed people's ability to analyze it. Thus, some new and efficient methods are needed to discover knowledge from large database. Association rule discovery is an important problem in knowledge discovery and data mining. The association mining task consists of identifying the frequent item sets and then forming conditional implication rules among them. In this paper, we describe and summarize recent work on association rule discovery, offer a new method to association rule mining and point out that association rule discovery can be applied in spatial data mining. It is useful to discover knowledge from remote sensing and geographical information system.

关键词： data mining association rule spatial data.

Spatial Variability of Micronutrients in Rice Grain and Paddy Soil

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Pedosphere 2009年第6期19卷 748-755页

作者： WANG Lin, WU Jia-Ping 2 , LIU Yan-Xuan, HUANG Hui-Qing and FANG Qian-Fang College of Environment and natural resources, Zhejiang university, Hangzhou 310029 (china) [a]College of Environment and natural resources Zhejiang University Hangzhou 310029 (China)

Consumption of rice is the main source of micronutrients to human in Asia. A paddy field with unknown anthro- pogenic contamination in Deqing County, Zhejiang Province, china was selected to characterize the spatial variability and distribution of micronutrients in rice grain and soil. A total of 96 paired soil and rice grain samples were collected at harvest. The micronutrients in the soil samples were extracted by diethylenetriamine pentaacetic acid （DTPA）. The mean micronutrient concentrations in rice grain were 3.85 μg Cu g^-1, 11.6 μg Fe g^-1, 39.7 μg Mn g^-1 and 26.0 μg Zn g^-1 The mean concentrations were 2.54μg g^-1 for DTPA-Cu, 133.5μg g^-1 for DTPA-Fe, 30.6μg g^-1 for DTPA-Mn, and 0.84μg g^-1 for DTPA-Zn. Semivariograms showed that measured micronutrients in rice grain were moderately dependent, with a range distance of about 110 m. The concentrations of the DTPA-extractable micronutrients all displayed strong spatial dependency, with a range distance of about 60 m. There was some resemblance of spatial structure between soil pH and the grain Cu, Fe, Mn, and Zn. By analogy, similar spatial variation was observed between soil organic matter （SOM） and DTPA-extractable table micronutrients in the soil. Kriging estimated maps of the attributes showed the spatial distributions of the variables in the field, which is beneficial for better understanding the spatial variation of micronutrients and for potentially refining agricultural management practices at a field scale.

关键词： correlation dependency kriging soil properties

Constructing Three-Dimension Space Graph for Outlier Detection Algorithms in Data Mining

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Wuhan university Journal of natural Sciences 2004年第5期9卷 585-589页

作者： ZHANG Jing 1,2 , SUN Zhi-hui 1 1.Department of Computer Science and Engineering, Southeast university, Nanjing 210096, Jiangsu, china 2.Department of Electricity and information Engineering, Jiangsu university, Zhenjiang 212001, Jiangsu, china Department of Computer Science and Engineering Southeast University. Nanjing 210096 Jiangsu China

Outlier detection has very important applied value in data mining literature. Different outlier detection algorithms based on distinct theories have different definitions and mining processes. The three-dimensional space graph for constructing applied algorithms and an improved GridOf algorithm were proposed in terms of analyzing the existing outlier detection algorithms from criterion and theory. Key words outlier - detection - three-dimensional space graph - data mining CLC number TP 311. 13 - TP 391 Foundation item: Supported by the National natural Science Foundation of china (70371015)Biography: ZHANG Jing (1975-), female, Ph. D, lecturer, research direction: data mining and knowledge discovery.

关键词： outlier detection three-dimensional space graph data mining

Comparing logic coverage criteria on test case prioritization

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Science china(information Sciences) 2012年第12期55卷 2826-2840页

作者： FANG ChunRong 1,2,CHEN ZhenYu 1,2 & XU BaoWen 1 1 State Key Laboratory for Novel Software technology,Nanjing university,Nanjing 210093,china 2 Software Institute,Nanjing university,Nanjing 210093,china 1. State Key Laboratory for Novel Software technology Nanjing University Nanjing 210093 China2. Software Institute Nanjing University Nanjing 210093 China

Logic coverage criteria have been widely used in the testing of safety-critical *** the past few years,fault-based logic coverage criteria have been studied intensively both in theory and in ***,there is a lack of authentic evidence of the comparison of fault-based logic coverage criteria with other logic coverage criteria,such as branch coverage and modified condition/decision coverage(MC/DC).In this paper,we present a comprehensive empirical study that compares these logic coverage criteria on test case prioritization,which is currently a hot topic in software *** useful conclusions are drawn from our research:(1) Fine-grained coverage criteria are always more effective and efficient.(2) The effectiveness of fault-based logic coverage criteria is not significantly different from that of MC/DC in terms of statistics,but the former is more stable.(3) A random strategy is more effective than branch coverage if a certain number of test cases are redundant.

关键词： fault detection capability logic coverage fault-based testing test case prioritization