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INITIAL VALUE PROBLEM FOR A CLASS OF NONLINEAR PARABOLIC SYSTEM OF FOURTH-ORDER

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Acta Mathematica Scientia 1991年第4期11卷 393-400页

作者：陈国旺 institute of Mathematics Zhengzhou University Zhengzhou China

In this paper, the periodic boundary problem and the initial value problem for the nonlinear system of parabolic type u1=-A（x, t）ux4+B（x, t）ux2+（g（u））x2+（grad h（u））x+f（u）are studied, where u（x, t）=(u1（x, t）.…, uJ（x, t） is a J-dimensional unknown vector valued function, f（u） and g（u） are the J-dimensional vector valued function of u（x, t）, h（u） is a scalar function of u, A（x, t） and B（x, t） are J×J matrices of functions. The existent, uniqueness and regularities of the generalized global solution and classical global solution of the problems are proved. When J=1, h（u）=0, g（u）=au3. A=a1, B=a2, where a1, a2 a are constants, the system is a generalized diffusion model equation in population problem.

关键词： valued uniqueness parabolic scalar matrices constants CLASS formulas uniformly 八布

The Simultaneous Approximation Order by Hermite Interpolation in a Smooth Domain

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Acta Mathematica Sinica,English Series 2002年第4期18卷 631-646页

作者： Tian Liang TU Department of Information Engineering, North china institute of Hydroelectricity, zhengzhou 450045, P. R. china Department of Information Engineering North China Institute of Hydroelectricity Zhengzhou 450045 P. R. China

Let D be a smooth domain in the complex plane. In D consider the simultaneous ap- proximation to a function and its ith (0≤i≤q) derivatives by Hermite interpolation. The orders of uniform approximation and approximation in the mean, are obtained under some domain boundary conditions. Some known results are included as particular cases of the theorems of this paper.

关键词： Simultaneous appoximation Hermite interpolation Approximation order Smooth domian

SIZE DISTRIBUTIONS OF COARSE SAND BED LOAD IN TURBULENT FLOW FIELD

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Journal of Hydrodynamics 1995年第3期7卷 1-6页

作者： Zhang Hong-wu Wang Shan(institute of Hydraulic Research Yellow River Conservancy Commissivn,zhengzhou 450003.P.R.{3.)

Putting forth effort on analyzing the action of turbulent flow on the sand particles on rvier bed surface,in this paper, the interdependent relation between the size distribution of coarse sand bed load and flow stren... 详细信息

关键词： coarse sand bed size distributions turbulent flow

Use-wear analysis confirms the use of Palaeolithic bone tools by the Lingjing Xuchang early human

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Chinese Science Bulletin 2010年第21期55卷 2282-2289页

作者： LI ZhanYang 1,4 & SHEN Chen 2,3.4 1 Henan Provincial institute of Cultural Relics and Archaeology,zhengzhou 450000,china 2 The Joint Laboratory of Human Evolution and Archaeometry,Chinese Academy of Sciences,Beijing 100044,china 3.The Royal Ontario Museum,Toronto ON M5S2C6,Canada 4 Oriental Archaeology Research Center of Shandong University,Jinan 250100,china Henan Provincial institute of Cultural Relics and Archaeology Zhengzhou 450000 China Oriental Archaeology Research Center of Shandong University Jinan 250100 China The Joint Laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing 100044 China The Royal Ontario Museum Toronto ON M5S2C6 Canada

During 2007-2008 excavations at the Lingjing site near Xuchang,Henan Province,dated back to around 100-80 ka ago,a large quantity of mammalian fossil remains were recovered along with a remarkable cluster of Early Modern Human(EMH) skull fragments in *** some of those animal bones were probably modified into tools.A use-wear analysis was carried out to examine the functions of modified bone *** results suggest that Lingjing bone tools were used for drilling,penetrating,and scraping animal substances,and that some might have been hafted during the *** study confirms that early existence ofintentionally-modified bone tools at human occupations of the early Late Pleistocene in northern *** discovery suggests making and use of bone tools were inevitably a part of early human behaviors and cultural development,as such of stone tools.

关键词：早期人类磨损分析旧石器时代工具许昌哺乳动物化石现代人类动物骨头

Jackson type theorems on complex curves

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Science china Mathematics 2009年第3期52卷 493-506页

作者： TU TianLiang Deptartment of Mathematics and Informatics, North china institute of Water Conservancy and Hydroelectric Power, zhengzhou 450011, china Deptartment of Mathematics and Informatics North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China

Let Γ be a closed smooth Jordan curve in the complex plane. In this paper, with the help of a class of fundamental functions of Hermite interpolation, the author introduces a continuous function interpolation which uniformly approximates to f(z) ∈ C(Γ ) with the same order of approximation as that in Jackson Theorem 1 on real interval [1, 1]. The accuracy of the order of approximation is proved. Using the method different from the early works, the author studies simultaneous approximation to function and its derivatives and the desired results analogues to that in Jackson Theorem 2 on real interval [1, 1] are obtained.

关键词： complex curves interpolation uniform approximation order of approximation 3.E05 3.E10 41A05 41A25 41A28

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铁路客车技术整备所线路配置规模研究

中国铁路 2024年第5期 118-123页

作者：张雄张正舟中铁二院工程集团有限责任公司四川成都610031 中国铁路经济规划研究院有限公司北京100038

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 10029—2009《铁路客车车辆设备设计规范》第4.3.2条规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用... 详细信息

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 10029—2009《铁路客车车辆设备设计规范》第4.3.2条规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用线性回归法和概率分析法对线路配置规模进行研究,并对该条规定在当前的适用性进行验证。研究结论如下:(1)按照列车运行图确定客车车底出入客车技术整备所的时间,分析其最大车底停留数量,从而确定整备线和车底停留线数量之和的方法,是确定客车技术整备所线路数量的准确方法。(2)按照入所车底数量和配置系数确定线路数量方法可行,全路客车技术整备所计算平均数量与运行图分析法计算结果的误差为0.3.~7.5%,符合性较好。(3.将3.计算方法应用到具体铁路客车整备所时,全路各所的均方根误差为25%~27%,该误差受运行图编制主客观因素影响,由各客运站列车终到/始发时间分布规律差异造成,可通过运行图调整来适应。

关键词：铁路客车整备所整备线停留线线路配置规模

维普期刊数据库博看期刊

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3.& ZHANG Xing4,5 1 College of Computer Science and Technology,Beijing University of Technology,Beijing 100022,china 2 State Key Laboratory of Information Security (Graduate University of the Chinese Academy of Sciences),Beijing 100049,china 3.School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,china 4 {3. of Electronic Technology,Information Engineering University,zhengzhou 450004,china 5 Trusted Computing Laboratory,Beijing University of Technology,Beijing 100022,china College of Computer Science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate University of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Effect of Addition of Sodium Dodecyl Sulfite on Physical Properties of Wheat Gluten Films

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Journal of Wuhan University of Technology(Materials Science) 2005年第2期20卷 15-19页

作者：曾瑜薇 School of Foreign Language Hubei University of TechnologyWuhan 430068China Assoc.Prof

Films were made from the wheat glutens treated with 5%,10%,15%,20%,25% and 3.%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a *** addition of SDS in wheat glutens prior to forming films significantly increased the elongation at break(E) (P<0.05) and reduced notably the water vapor permeability(WVP) (P<0.05). In contrast,a decrease in the tensile strength(TS) of the films from gluten containing-SDS was ***,a significant decrease in P_(O_2) and P_(CO_2) of films from gluten treated with SDS was noticed. Although SDS-treated gluten film was slightly more yellow and darker than control one, it was not visually detrimental. It is indicated that the treatment with SDS prior to forming films greatly enhances the mechanical properties of wheat gluten *** obivous improvement in water vapor permeability and extensibility of gluten films means that the use of SDS is a potential choice for improving properties of gluten films. The edible film was used to preserve tomatoes. The experimental results show that the shelf life of tomatoes coated with the edible film is extended, and the nutritional quality is kept well.

关键词： wheat gluten sodium dodecyl sulfite (SDS) tensile strength (TS) elongation at break(E) water vapor permeability(WVP) tomato preservation

A novel logic-based automatic approach to constructing compliant security policies

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Science china(Information Sciences) 2012年第1期55卷 149-164页

作者： BAO YiBao1,2,4,YIN LiHua1,FANG BinXing 1,3.GUO Li 1 1institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190,china 2institute of Electronic Technology,Information Engineering University,{3. 450004,china 3.eijing University of Posts and Telecommunications,Beijing 100190,china 4Graduate University,the Chinese Academy of Science,Beijing 100049,china 1. institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China4. Graduate University the Chinese Academy of Science Beijing 100049 China3. Beijing University of Posts and Telecommunications Beijing 100190 China

It is significant to automatically detect and resolve the incompliance in security *** existing works in this field focus on compliance verification,and few of them provide approaches to automatically correct the incompliant security *** paper proposes a novel approach to automatically transform a given security policy into a compliant *** security policy Π and delegation policy M declared by logic programs,the approach automatically rewrites Π into a new one ΠM which is compliant with M and is readable by the *** prove that the algorithm is sound and complete under noninterference ***,we show that the security policy query evaluation algorithm with conflict and unsettlement resolution still works very well on Π*** approach is automatic,so it doesn't require a administrator with excess *** this sense,our proposal can help us to save much manpower resource in security management and improves the security assurance abilities.

关键词： security policy rewriting logic program compliance