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A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(college of Life Science,sichuan university,chengdu 610064.{4.) (college of Life Science Sichuan University Chengdu 610064 China) *Correspondence: Xing-Jin HE *Correspondence: E-mail: xjhe@*** Tel.: 86-28-854.5006 Fax: 86-28-854.5006.

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to china that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.

QUANTITATIVE APPROACH TO INFLUENCES OF HIGH SEDIMENT LADEN INUNDATION FLOWS ON THE MORPHOLOGICAL VARIATION OF FLOODPLAINS

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Journal of Hydrodynamics 2007年第1期19卷 9-17页

作者： ZHANG Xin-hua LONG Wen-fei LEI Xiao-zhang ZHANG Xiang-wei XIE He-ping WANG Jiang-ping State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China college of Hydraulic and Hydroelectric Engineering Sichuan University Chengdu 610065 China Department of Planning and Program Ministry of Water Resources ofP. R. China Beijing 100053 China Guizhou Hongfu Company Fuqian 550501 China

This article mainly aims at developing an integrated 2-D numerical simulation model on inundation, sediment transportation and the morphological variations of floodplains due to high sediment-laden inundation flows. Due to the complexity of inner and outer boundaries and the arbitrary structures within the computational domain of floodplains, an unstructured Finite-Volume Method （FVM） based on an irregular polygon mesh was worked out so that the influences of complex boundaries can be integrated into the simulation. A case study was conducted in the Lower Yellow River Basin, in which a dike-break at the Huayuankou Hydrological Station was assumed to happen when a flood scale of 1982 was suffered in the region. The simulated spatial distribution of sediment deposition and erosion can be used to reasonably explain the natural phenomena of ＂suspended river＂ of the lower part of the Yellow River. It is concluded that the inundation process of water is similar to a variable-river-bed condition during the simulation because the sediment deposition and erosion are modified by new values at the end of each time step. The mass and momentum conservation were strictly followed during the simulation. Therefore, the prediction of floodplain evolutions by the integrated simulation model, proposed in this study, can be adequately and accurately given if the real condition of an floodplain can be obtained in detail.

关键词： dike-break Shallow Water Equations (SWE),irregular polygon mesh Finite Volume Method (FVM) floodinundation morphological variation of floodplain

Energy-Based Prediction of Low Cycle Fatigue Life of High-Strength Structural Steel

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Journal of Iron and Steel Research International 2012年第10期19卷 47-53页

作者： LUO Yun-rong1,2, HUANG Chong-xiang1, GUO Yi2, WANG Qing-yuan1 (1. college of Architecture and Environment, sichuan university, chengdu 610065, sichuan,{4. 2. college of Mechanical Engineering, sichuan university of Science and Engineering, Zigong 64.000, sichuan,{4.) [a] college of Architecture and Environment. sichuan university Chengdu 610065 Sichuan China [b] college of Mechanical Engineering. sichuan university of Science and Engineering Zigong 643000 Sichuan China

Energy-based models for predicting the low-cycle fatigue life of high-strength structural steels are presented. The models are based on energy dissipation during average of cycles, cycles to crack propagation and total cycles to failure. Plastic strain energy per cycle was determined and found as an important characteristic for initiation and propagation of fatigue cracks for high-strength structural steels. Fatigue strain-life curves were generated using plastic energy dissipation per cycle (loop area) and compared with the Coffin-Manson relation. Low cycle fatigue life was found similar from both methods. The material showed Masing-type behavior. The cyclic hysterisis energy per cycle was calculated from cyclic stress-strain parameters. The fracture surfaces of the fatigue samples were characterized by scanning electron microscope and the fracture mechanisms were discussed.

关键词： low cycle fatigue high-strength steel energy-based model fatigue life

Integrated optimization methods in multisensor decision and estimation fusion

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Science china(Information Sciences) 2012年第3期55卷 545-550页

作者： LUO YingTing, SHEN XiaoJing & ZHU YunMin college of Mathematics, sichuan university chengdu, 610064. china 1. college of Mathematics Sichuan University Chengdu 610064 China

This paper presents a significant integrated optimization point of view behind the following three successful decision and estimation fusion results: 1) a unified fusion rule for networked sensor decision systems; 2) optimal sensor data quantization for estimation fusion and 3) integrated multi-target data association tracking systems. More precisely speaking, the integrated optimization method in 1) derives a unified objective function optimizing only sensor rules given a unified fusion rule; the method in 2) derives a unified objective function optimizing both the sensor quantization rule and the final estimation in the MSE sense, and the method in 3) integrates all associated targets and their valid observations into a whole random measurement matrix dynamic system so that the optimal random matrix Kalman filtering can be applied to estimate the states of all associated targets.

关键词： integrated optimization decision fusion estimation fusion data association

A KIND OF FUZZY MULTI-OBJECTIVE LINEAR PROGRAMMING PSOBLEMS BASED ON INTER VALVALUED FUZZY SETS

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Journal of Systems Science & Complexity 2001年第2期14卷 149-158页

作者： XU Jiuping (Department of Applied Mathematics, sichuan university, chengdu 610065, china) 四川大学四川成都 610065

This paper presents a general solution procedure and an interactive fuzzy satisfying method for a kind of fuzzy multi-objective linear programming-problems based on interval valued fuzzy sets. Firstly, a fuzzy set of the fuzzy solutions, which can be focused on providing complete information for the final decision, can be obtained by the proposed tolerance analysis of a non-dominated set. Secondly, the satisfying solution for the decisionmaker can be derived from Pareto optimal solutions by updating the current reference membership levels on the basis of the current levels of the membership functions together with the trade-off rates between the membership functions.

关键词： Fuzzy number interval-valued fuzzy sets multiple objective linear programming interactive fuzzy satisfying method parametrically interval values.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and Resources Science, sichuan Normal university, chengdu 610066, sichuan,{4. 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 61004., sichuan,{4. 3. Graduate university of the Chinese Academy of Sciences, Beijing 10004.,{4. 4. Information Center of Land and Resources Department of sichuan Province, chengdu 61004., sichuan,{4. The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land Resources Department of sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Notes on the Borwein-Choi Conjecture of Littlewood Cyclotomic Polynomials

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Acta Mathematica Sinica,English Series 2009年第1期25卷 65-76页

作者： Shao Fang HONG Wei CAOMathematical college, sichuan university, chengdu 610064. P. R. china Mathematical college Sichuan University Chengdu 610064 P. R. China

Borwein and Choi conjectured that a polynomial P（x） with coefficients ±1 of degree N - 1 is cyclotomic iffP（x）=±Φp1（±x）ΦP2（±x^p1）…Φpr（±x^p1p2…pr-1）,where N = P1P2 … pτ and the pi are primes, not necessarily distinct. Here Φ（x）：= （x^p - 1）/（x - 1） is the p-th cyclotomic polynomial. They also proved the conjecture for N odd or a power of 2. In this paper we introduce a so-called E-transformation, by which we prove the conjecture for a wider variety of cases and present the key as well as a new approach to investigate the coniecture.

关键词： cyclotomic polynomial Littlewood polynomial E-transformation Ramanujan sum least element

ON THE SPACES OF THE MAXIMAL POINTS

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Chinese Annals of Mathematics,Series B 2003年第3期24卷 303-308页

作者： LIANG JIHUA LIU YINGMING Institute of Mathematics, sichuan university, chengdu 610064. china. Institute of Mathematics, sichuan university, chengdu 610064. china. sichuan Univ Math Inst Chengdu 610064 Peoples R China

For a continuous domain D, some characterization that the convex powerdomain CD is adomain hull of Max(CD) is given in terms of compact subsets of D. And in this case, it isproved that the set of the maximal points Max(CD) of CD with the relative Scott topology ishomeomorphic to the set of all Scott compact subsets of Max(D) with the topology induced bythe Hausdorff metric derived from a metric on Max(D) when Max(D) is metrizable.

关键词： Convex powerdomain Maximal points Hausdorff metric

APPLICATIONS OF THE THEORY OF CAMINA GROUPS

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 39-50页

作者： REN YONGCAI(Department of Mathematics,sichuan Union university,chengdu 610064.china) sichuan Union Univ Dept Math Chengdu 610064 Peoples R China

In this papert the author first gives a conjugacy-class version of Camina hypotheses andthen applys the Camina group theory to discussing two classes of finite groups.

关键词： Camina groups Applications Characters