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Taxonomic revision of Lepisorus(***.) Ching ***(Polypodiaceae) from china

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Journal of Systematics and Evolution 2009年第6期47卷 581-598页

作者： ~(1,2)Xin-Ping QI ~1Xian-Chun ZHANG~* 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2({5. University of chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate University of chinese academy of sciences Beijing 100049 China)

The taxonomy of Lepisorus(***.) Ching *** in china was revised based on herbarium specimen examinations,field observations,and microscopic study of rhizome scales,soral paraphyses,leaf epidermis, and *** a result,nine species were recognized:Lepisorus macrosphaerus(Baker) Ching,Lepisorus asterolepis (Baker) Ching,Lepisorus marginatus Ching,Lepisorus kuchenensis(***) Ching,Lepisorus megasorus(***.) Ching,Lepisorus kawakamii(Hayata) Tagawa,Lepisorus subsessilis Ching & ***,Lepisorus affinis Ching, and Lepisorus nudus(Hook.) *** kawakamii(Hayata) Tagawa was reinstated;Lepisorus gyirongensis Ching & *** and Lepisorus longus Ching were reduced to synonyms *** and ***,respectively. The subdivision ofLepisorus macrosphaerus was not *** scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric *** of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus.

关键词： china Lepisorus Lepisorus sect.Lepisorus Polypodiaceae taxonomic revision

Conceptual design and simulation analysis of thermal behaviors of TGR blast furnace and oxygen blast furnace

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Science china(Technological sciences) 2010年第1期53卷 85-92页

作者： ZHANG Hui1,2,LI HuiQuan1,TANG Qing1 & BAO WeiJun1 1 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,chinese academy of sciences,beijing 100190,china 2 {5. University of chinese academy of sciences,beijing 100049,china National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate University of chinese academy of sciences Beijing China

Extensive use of carbon based fuel is the main inducement for global warming and more extreme *** carbon dioxide emission and enhancing energy use is a common subject in steel *** the integrated steel plant,decreasing carbon dioxide emission must consider energy balance in the whole iron and steel works,and secondary energy must be actively *** promising blast-furnaces,top gas recovery blast furnace(TGR-BF) and oxygen blast furnace have been *** this paper,conceptual TGR blast furnace and oxygen blast furnace are *** on the idea of blast furnace gas de-CO2 circulating as reducing agent and the idea of pure oxygen blast decreasing the thermal reserve zone temperature,process modeling is conducted with ASPEN *** is shown that the developed model reasonably describes the energy balance and mass balance feature of the furnace,and provides basic thermodynamic condition for *** effects of changes in different operation conditions are studied by sensitivity analysis and reference data from simulation.

关键词： TGR blast-furnace thermal behavior simulation analysis CO2 emission decreasing

Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3,JIN ZHi1,2 & WU Budan1,4 1. academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080,{5. 2. Institute of Computing Technology, chinese academy of sciences, beijing 100080,{5. 3. Institute of Software, chinese academy of sciences, beijing 100080,{5. 4. graduate University of chinese academy of sciences, beijing 100049,{5. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Institute of Software Chinese Academy of Sciences Beijing China Institute of Computing Technology Chinese Academy of Sciences Bejing China graduate University of chinese academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Rate of strong consistency of quasi maximum likelihood estimate in generalized linear models

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Science china Mathematics 2004年第6期47卷 882-893页

作者： YUE Li & CHEN Xiru School of Mathematics and Statistics, Wuhan University, Wuhan 430072, china graduate School, chinese academy of sciences,{5., china School of Mathematics and Statistics Wuhan University Wuhan China graduate School Chinese Academy of Sciences Beijing China

Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-likelihood equation for the GLM has a solution when the sample size n is sufficiently large. The rate of this solution tending to the true value is determined. In an important special case, this rate is the same as specified in the LIL for iid partial sums and thus cannot be improved anymore.

关键词： quasi-likelihood function generalized linear models strong consistency

Mechanism and Defense on Malicious Code

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Wuhan University Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2,3, QING Si-han 1,2,31. Institute of Software, the chinese academy of sciences, beijing 100080, china 2.Engineering Research Center for Information Security Technology, the chinese academy of sciences, beijing 100080, china 3.graduate School of the chinese academy of sciences, beijing 100080, china Institute of Software the Chinese Academy of Sciences Beijing China Engineering Research Center for Information Security Technology the Chinese Academy of Sciences Beijing China graduate School of the chinese academy of sciences Beijing China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

MicroRNA (miR396) negatively regulates expression of ceramidase-like genes in Arabidopsis

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Progress in Natural Science:Materials International 2009年第6期19卷 781-785页

作者： Dongmei Liu a,b, Diqiu Yu a, a Xishuangbanna Tropical Botanical Garden, chinese academy of sciences, Kunming 65.223, china b graduate School of the chinese academy of sciences, beijing 100049, china Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China graduate School of the chinese academy of sciences Beijing 100049 China

MicroRNAs (miRNAs) are 21-23 nucleotide (nt), endogenous RNAs that regulate gene expression by targeting mRNAs for direct cleavage or translational repression in plants. In Arabidopsis, miR396 is encoded by two different loci (MIR396a and MIR396b) and sequence analysis suggests it may target three ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2 and Atceramidase-like 3). To demonstrate the biological function of miR396, we inserted the synthetic precursors, MIR396a or MIR396b, under the control of the enhanced cauliflower mosaic virus (CaMV) 35. promoter, into a plant transformation vector (pOCA30) and transformed the constructs into Arabidopsis. The promoter increased miR396 levels by more than 2-fold, indicating appropriate maturation of the synthetic precursor MIR396a or MIR396b transcript in transgenic plants. Microarray analysis showed that the transcript levels of two ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2) were decreased by more than 2-fold and lactosylceramide 4-a-galactosyltransferase increased by more than 2-fold in transgenic plants compared with the empty vector-transformed plants. Northern blot analysis showed that the mRNA levels of the two ceramidase-like genes were significantly reduced in transgenic plants. These results indicated that miR396 probably plays a crucial role in the ceramide metabolism pathway by negatively regulating the expression of ceramidase-like genes in Arabidopsis.

关键词： miR396 miR396 precursor Ceramidase Ceramide

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2 , ZHANG Youshui 3 1. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, china 2. graduate University of chinese academy of sciences, beijing 100049, china 3. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate University of chinese academy of sciences Beijing China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 25. basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3 & SHAO Xuemei1,21. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101,{5. 2. Institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085.{5. 3. graduate School of chinese academy of sciences,{15.,{5. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate School of chinese academy of sciences Beijing China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5. and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3) The PC1 (the first principal component derived from DLH1-DLH5.series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

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Progress in Natural Science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (State Key Laboratory of Information Security, graduate School of chinese academy of sciences, beijing 100049,{5.) State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing 100049 China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2 , where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.