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The C-topology on lattice-ordered groups

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Science china Mathematics 2009年第11期52卷 2397-2403页

作者： YANG YiChuan Department of Mathematics,key laboratory of ministry of education for Information Mathematics and Behavior,Beihang university,beijing,100191 china 1. Department of Mathematics Key Laboratory of Ministry of Education for Information Mathematics and Behavior Beihang University 100191 Beijing China

Let A be a lattice-ordered group. Gusi? showed that A can be equipped with a C-topology which makes A into a topological group. We give a generalization of Gusi?’s theorem, and reveal the very nature of a “C-group” of Gusi? in this paper. Moreover, we show that the C-topological groups are topological lattice-ordered groups, and prove that every archimedean lattice-ordered vector space is a T 2 topological lattice-ordered vector space under the C-topology. An easy example shows that a C-group need not be T 2. A further example demonstrates that a T 2 topological archimedean lattice-ordered group need not be C-archimedean, either.

关键词： C-topology lattice-ordered group archimedean lattice-ordered group Hausdorff topology vector space 06F30 22A99

Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2, SHEN Zhenyao1 and LI Jianqiang3(1. State key laboratory of Water Environment Simulation, School of Environment, beijing Normal university, beijing 100875, china 2. key laboratory for Water and Sediment Sciences ministry of education, School of Environment, beijing Normal university, beijing 100875, china 3. Water resources and Hydropower Planning and Design General Institute, MWR, beijing 100011, china) State key laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China key laboratory for Water and Sediment Sciences ministry of education School of Environment Beijing Normal University Beijing 100875 China Water resources and Hydropower Planning and Design General Institute MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

Hopping control channel MAC protocol for opportunistic spectrum access networks

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The Journal of china Universities of Posts and Telecommunications 2010年第6期17卷 65-71页

作者： FU Jing-tuan,JI Hong,MAO Xu key laboratory of Universal Wireless Communications,ministry of education,beijing university of Posts and Telecommunications,beijing 100876,china [a] key laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts Telecommunications Beijing 100876 China

Opportunistic spectrum access （OSA） is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access （CHMA） protocol,we introduce a hopping control channel medium access control （MAC） protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users＇ occupancy of the channel,we use a primary user （PU） detection model to calculate the channel availability for unlicensed users＇ access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

关键词： channel hopping MAC protocol OSA Markov chain

Bandwidth allocation and admission control scheme based on Nash bargaining solution for WiMAX systems

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 53-58页

作者： CAI Dao-jin ,JI Hong,LI Xi key laboratory of Universal Wireless Communications,ministry of education,beijing university of Posts and Telecommunications,beijing 100876,china [a] key laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts Telecommunications Beijing 100876 China

Development of fair and efficient bandwidth allocation and admission control schemes is one of the key issues in the design of IEEE 802.16 broadband wireless access systems in time division multiple access （TDMA） mode. In this article, the problem of bandwidth allocation and admission control is formulated as a Nash bargaining model. The nash bargaining solution （NBS） derived from the cooperative game is adopted to maximize the spectrum utilization. Analysis and simulation results show that there is a unique Pareto optimal bandwidth allocation solution by using NBS among various flows. Furthermore, maximum utility of the system can also be maintained by using the admission control policy with different number of connections and variable channel qualities. The total throughput of the proposed scheme is close to the maximal one, while significantly improving fairness compared to the existing solutions.

关键词： NBS game theory bandwidth allocation admission control IEEE 802.16

MAPK signal pathways in the regulation of cell proliferation in mammalian cells

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Cell Research 2002年第1期12卷 9-18页

作者： WEI ZHANG, Hui Tu LIU The key laboratory of Cell Proliferation and Regulation Biology of ministry of education, College of Life Sciences, beijing Normal university, beijing 100875, china 1The key laboratory of Cell Proliferation and Regulation Biology of ministry of education College of Life Sciences Beijing Normal University Beijing 100875 China 1The key laboratory of Cell Proliferation and Regulation Biology of ministry of education College of Life Sciences Beijing Normal University Beijing 100875 China

MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.

关键词： MAPK ER.K JNK/SPAK p38 cell proliferation cross-talk.

Using factor analysis scales of generalized amino acid information for prediction and characteristic analysis of β-turns in proteins based on a support vector machine model

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Science china Chemistry 2010年第5期53卷 1160-1166页

作者： LIANG GuiZhao & ZHAO Wei key laboratory of Biorheological Science and technology(Chongqing university),ministry of education Bioengineering College,Chongqing university,Chongqing 400044,china 1. key laboratory of Biorheological Science and technology (Chongqing university) Ministry of Education Bioengineering College Chongqing University Chongqing 400044 China

This paper offers a new combined approach to predict and characterize β-turns in *** approach includes two key steps,i.e.,how to represent the features of β-turns and how to develop a *** first step is to use factor analysis scales of generalized amino acid information(FASGAI),involving hydrophobicity,alpha and turn propensities,bulky properties,compositional characteristics,local flexibility and electronic properties,to represent the features of β-turns in *** second step is to construct a support vector machine(SVM) predictor of β-turns based on 426 training proteins by a sevenfold cross validation *** SVM predictor thus predicted β-turns on 547 and 823 proteins by an external validation test,*** results are compared with the previously best known β-turn prediction methods and are shown to give comparative *** significantly,the SVM model provides some information related to β-turn residues in *** results demonstrate that the present combination approach may be used in the prediction of protein structures.

关键词： β-turns factor analysis scales of generalized amino acid information support vector machine

Influence of Ru addition on microstructure and stress-rupture property of Ni-based single crystal superalloys

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Progress in Natural Science:Materials International 2010年第1期20卷 61-69页

作者： Jing-yang CHEN~1,Qiang FENG~(1,2),La-mei CAO~3,Zu-qing SUN~1 1.State key laboratory for Advanced Metals and Materials,university of Science and technology beijing, beijing 100083.china 2.National Center for Materials Service Safety,university of Science and technology beijing,beijing 100083.china 3.National key laboratory of Science and technology on Advanced High Temperature Structural Materials, beijing Institute of Aeronautical Materials,beijing 100095,china Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Univ Sci & Technol beijing Natl Ctr Mat Serv Safety Beijing 100083 Peoples R China beijing Inst Aeronaut Mat Natl Key Lab Sci & Technol Adv High Temp Struct M Beijing 100095 Peoples R China

The effects of Ru on the microstructure and stress-rupture property were investigated in two experimental Ni-based single crystal superalloys with and without Ru addition(5.1%,mass fraction).The results indicate that the morphology ofγ' precipitates in the dendrite core and interdendritic region are intermediate and nearly spherical,respectively,in the Ru-free alloy after being aged at 1100℃for 8 *** Re partitioning ratio increases due to Ru addition and Ru partitioned preferentially to theγphase in both dendrite core and interdendritic region of the Ru-containing alloy,which results in more negative lattice misfit and more cuboidalγ' ***,theγ' volume fraction increases while the precipitate size and y channel width decreases due to Ru addition in both dendrite core and interdendritic *** addition improves the stress-rupture life at 1100℃/140 MPa significantly due to higherγ' volume fraction,more negative lattice misfit and a well rafting structure as well as lessγchannel width.

关键词： Ni-based superalloys ruthenium elemental partitioning ratio lattice misfit γ’ morphology stress-rupture property

Effects of chronic exposure to nonylphenol on locomotor activity and social behavior in zebrafish(Danio rerio)

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Journal of Environmental Sciences 2010年第9期22卷 1435-1440页

作者： Jigang Xia,Cuijuan Niu ,Xuejiao Pei ministry of education key laboratory of Biodiversity Science and Ecological Engineering,College of Life Sciences,beijing Normal university,100875 beijing,china. [a] ministry of education key laboratory of Biodiversity Science Ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing China

Nonylphenol （NP）, a xenoestrogen ubiquitously found in aquatic ecosystems, is of high environmental concern. The present work assessed the effects of exposure to NP on locomotor activity and social behavior in male and female zebrafish （Danio rerio）, to evaluate the possible hazard of NP to fish behavior and to pursue a potential biomarker of NP contamination. Fish were randomly divided into six groups. Five groups were receiving 0.1, 1, 10, 50 and 100 μg/L nominal concentrations of NP for 60 days, respectively. A sixth control group was given the same treatment as the other five groups, but no NP. Locomotor activity, aggressive behavior, group preference and leaving shoal were examined. NP exposure showed marked influence on locomotor activity of the male zebrafish, whereas that of the female was not significantly affected by NP. Aggressive behavior and group preference were significantly affected by NP exposure in both male and female groups. Locomotor activity and aggressive behavior of the male and group preference of both male and female zebrafish were clearly inhibited at 100 μg/L NP. No significant alteration in leaving shoal was observed under NP exposure. The results suggested that changes in locomotor activity and aggressive behavior of the male and group preference of both male and female may be used as an ecologically relevant integrative biomarker of NP contamination.

关键词： chronic toxicity nonylphenol biomarker zebrafish

Extracting Gold Fines from Pyrite Slag by Hydrophobic Flocculation Flotation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 1-4页

作者： Ruihua Li Jirang Cui Shaoxian Song Shouci Lu (resources Engineering School, university of Science and technology beijing, beijing 100083, china) resources Engineering School University of Science and Technology Beijing Beijing 100083 China

In order to extract gold fines from pyrite slag, the hydrophobic flocculation flotation (HFF) was studied and compared with conventional flotation. The main parameters of HFF such as flotation reagent, surfactant dosage. the duration of agitation and the amount of non-polar oil were investigated, and the effect of non-polar oil was analyzed particularly. It is demonstrated that the HFF is better for gold extraction from pyrite slag than the conventional flotation, and the non-polar oil and the intensive agitation are the key to improve the Au contents and recovery in the concentrate. HFF was used to treat the pyrite slag from the west of Jiangxi province, whose gold contentsare 2.949/t and the size of which are smaller than 10μm. The gold concentrate with gold grade 126.3 g/t and 51 .35% recovery was obtained. Thus, a new method of extracting gold fines from pyrite slag is developed using HFF.

关键词： pyrite slag hydrophobic flocculation flotation gold