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Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1** and CHEN Wende2(1. School of Mathematical sciences, Peking university, Beijing 100871, china 2. Laboratory of Systems and Control and Key State Laboratory of Information Security, Institute of Systems science, Academy of mathematics and Systems science, Chinese Academy of sciences, Beijing 100080, china) School of Mathematical sciences Peking University Beijing 100871 China Laboratory of Systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

The genus distributions for a certain type of permutation graphs in orientable surfaces

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science china mathematics 2007年第12期50卷 1748-1754页

作者： Rong-xia HAO~(1+) Wei-li HE~1 Yan-pei LIU~1 Er-ling WEI~2 ~1 Department of mathematics,Beijing Jiaotong university,Beijing 100044,china ~2 School of Information,Renmin university of china,Beijing 100872,china Department of mathematics Beijing Jiaotong University Beijing China School of Information Renmin University of China Beijing China

A circuit is a connected nontrivial 2-regular graph. A graph G is a permutation graph over a circuit C, if G can be obtained from two copies of C by joining these two copies with a perfect matching. In this paper, based on the joint tree method introduced by Liu, the genus polynomials for a certain type of permutation graphs in orientable surfaces are given.

关键词： graph, genus distribution, genus, surfaces

Microstructure,Compression Property and Shape Memory Effect of Equiatomic TaRu High Temperature Shape Memory Alloy

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Journal of Materials science & technology 2004年第1期20卷 97-99页

作者： Xin GAO, Yufeng ZHENG, Wei CAI, Su ZHANG and Liancheng ZHAOSchool of Materials science and Engineering, Harbin Institute of technology, Harbin 150001, china Sch. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

The microstructure, phase transformation, compression property and strain recovery characteristics of equiatomic TaRu super high temperature shape memory alloy have been studied by optical microscope, XRD, DTA, compression tests and TEM observations. When cooling the alloy specimen from high temperature to the room temperature, β(parent phase)→β'(interphase) β→' (martensite) two-step phase transformations occur. The microstructure at room temperature show regularly arranged band morphology, with the monoclinic crystal structure. The twinning relationship between the martensite bands is determined to be (101) of Type I. Reorientation and coalescence of the martensite bands inside the variant happened during compression at room temperature. The β'→β reversible transformation contributes mainly the shape memory effect, with the maximum completely recovery strain of 2%.

关键词： TaRu alloy Phase transformation Microstructure Shape memory effect

香港科技大学(广州)全新“枢纽-学域”学术组织架构理念——访香港科技大学(广州)副校长(教学)吴景深教授

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中国塑料 2024年第3期38卷 126-127页

作者：《中国塑料》编辑部《中国塑料》编辑部

香港科技大学(简称港科大)自1991年创立以来,秉持锐意创新、与时并进、博大包容、坚持原创的理念,在教育、科研和知识转移等方面均取得长足进展。香港科技大学(广州)[简称港科广]以其融合学科架构,与港科大的深厚学科根基相辅相成,展示... 详细信息

香港科技大学(简称港科大)自1991年创立以来,秉持锐意创新、与时并进、博大包容、坚持原创的理念,在教育、科研和知识转移等方面均取得长足进展。香港科技大学(广州)[简称港科广]以其融合学科架构,与港科大的深厚学科根基相辅相成,展示港科大重塑未来教育模式的理想与抱负。《中国塑料》编辑部前往港科广,拜访了港科广副校长(教学)吴景深教授,深入了解了港科广全新的学科建设理念和科研理念。

关键词：副校长中国香港科技大学知识转移学科架构科研理念组织架构景深学科建设

Fair Electronic Payment Scheme Based on DSA

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Wuhan university Journal of Natural sciences 2005年第1期10卷 203-206页

作者： WANGShao-bin HONGFan ZHUXian CollegeofComputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074HubeiChina

We present a multi-signature scheme based on DSA and describes a faireleetronic payment scheme based on improved DSA signatures. The scheme, makes both sides in e-qualpositions during the course of electronic transaction A Trusted Third Party (TTP)is involved in thescheme to guarantee the fairness of the scheme for both sides. However, only during the course ofregistration and dispute resolution will TTP be needed TTP is not needed during the normal paymentstage.

关键词： fair electronic payment multi-signatures DSA signatures E-commerce

GRAVITATIONAL SCINTILLATION, ANISOTROPIES OF BACKGROUND RADIATION AND DENSITY INHOMOGENEITIES OF COSMIC MATTER

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science in china,Ser.A 1983年第3期 297-305页

作者：方励之 Astrophysics Research Division university of science and technology of{3. hefei

The stochastic component in density inhomogeneities of cosmic matter can cause the intensity scintillation of sources at cosmological distance. This scintillation effect is one of the origins of small angular anisotropy in the microwave background. That is, the density inhomogeneities in the epoch after the recombination would also contribute to the formation of background anisotropy. Therefore, an upper limit for the density inhomogeneities of cosmic matter can be obtained by the observation of small angular anistropy of background radiation. The result is that, if the universe is closed, a strong inhomogeneity has never been evolved in the distribution of total density (including visible and invisible matter), namely, even at the present the total density distribution might still be rather homogeneous.

关键词： GRAVITATIONAL SCINTILLATION ANISOTROPIES OF BACKGROUND RADIATION AND DENSITY INHOMOGENEITIES OF COSMIC MATTER

A Study on Some Games Problems in Social Choice

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Systems science and Systems Engineering 1996年第4期6卷 397-401页

作者： ZHAO Yong YUE Chaoyuan CHEN Ting(Huazhong university of science and technology Wuhan, 43.074,{3.)

This paper firstly analyzed and researched the individual strategic behavior in social choice in the view of games. Then, a player’s voting strategic solution was probled into. Some solving methods were given and som... 详细信息

关键词： social choice games performance strategy

The formation mechanism of high-quality dolomite reservoir in the deep of Puguang Gas Field

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science china Earth sciences 2008年第S1期51卷 53-64页

作者： MA YongSheng 1 ,GUO TongLou 1 ,ZHAO XueFeng 2 &CAI XunYu 1 1 Southern Exploration&Production Company,Sinopec,Kunming 650200,china 2 china university of Mining and {3.,Beijing 100083.china Southern Exploration & Production Company Sinopec China china university of Mining and technology Beijing China

The discovery of Puguang Gas Field provides the exploration of china deep marine carbonate rock with important *** Puguang Gas Field,the dolomite reservoirs discovered in the deep are the best in the present of china,which present big thickness and wide-range distribution,and develop abundant secondary *** researches show that Puguang Gas Field bears the characteristics of early gas-filling time,deep burial,high matured organic matter and long-term interaction of hydrocarbon(oil and gas)-water-rock(carbonate reservoir).The developments of secondary pores in this area are affected by multiple diagenesis and their formation mechanisms are *** the research on depositional environment,sedimentary facies and reservoir porosity characters of Changxing and Feixianguan Formations,it is thought that high-quality dolomite reservoirs of Puguang Gas Field form on the favorable sedimentary facies belts,which are the integrate result affected by several factors including superficial corrosion,burial corrosion,overpressure and tectonic movement,among which burial corrosion of TSR to reservoir and overpressure formed by thermal evolution of organic matter have great effect on the formation of secondary porosity of Changxing and Feixianguan Formations.

关键词： deep high-quality reservoir dolomite corrosion Puguang Gas Field Sichuan Basin

Investigation of the Microstructure of Rolled Semi-Solid Steel

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Journal of Materials science & technology 2002年第3期18卷 281-282页

作者： Renbo SONG, Yonglin KANG, Jianlin SUN, Xiongfei YANG, Aimin ZHAO and Weimin MAODepartment of Metal Forming, university of science and technology Beijing, Beijing 100083.{3. [ Manuscript received March 15, 2001, in revised form May L5, 2001] Dept. of Metal Forming Univ. of Sci. and Technol. Beijing Beijing 100083 China

In this paper, spring steel-60Si2Mn and stainless steel-1Cr18Ni9Ti were rolled one pass in the semi-solid state. The microstructural evolution during rolling of the steels with different solid fraction was investigated. The experimental results showed that the manner of liquid and solid phases flowing and deforming was different. During rolling, most of solid phases remained in the center of the rolled specimens, while liquid phase flowed to the edge, which resulted in the macrosegregation of liquid and solid phases. Only the amount of solid fraction reached a certain value, were the solid phases deformed and flattened.

关键词： Spring steel Stainless steel Semi-solid Microstructure