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A New (t, n) Threshold Signature Scheme Withstanding the Conspiracy Attack

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Wuhan university Journal of Natural Sciences 2005年第1期10卷 107-110页

作者： XIE Qi 1,2, YU Xiu-yuan 3 1.Department of Mathematics, Zhejiang university, Hangzhou 310027, Zhejiang,China 2.school of Information and engineering, Hangzhou Teachers College, Hangzhou 310012, Zhejiang, China 3.Hangzhou Teachers College, Hangzhou 310012, Zhejiang, China Dept. of Math. Zhejiang Univ. Hangzhou 310027 China Sch. of Info. and Eng. Hangzhou Teachers Coll. Hangzhou 310012 China Hangzhou Teachers Coll. Hangzhou 310012 China

A ccmspiracy attack is proposed to show that Wang-Li's scheme is instcure,because any t or more group members can impersonate other t member to sign any message withoutholding the responsibility. To avoid the conspiracy attack, this paper prestentsa new (t,n)threshold signature scheme with traceablt signers. A (t. n) threshold signature scheme allows t ormore group members of the group lo generate a signature on behalf of the group, Any less than tmembers cannot generate a valid signature, andany set of the group cannot impersonate another set ofmembers to sign any message without holding the responsibility. In case of disputes., the thresholdsignature can be opened, so that the original signers ean be traced without repealing the secretkeys.

关键词： cryptography threshold signature conspiracy attack identifier tracing

The Testing Strength Curves of Lightweight Aggregate Concrete by Rebound Method and Ultrasonic-rebound Combined Method

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Journal of Wuhan university of Technology(Materials Science) 2011年第5期26卷 1010-1017页

作者：荣辉 school of Materials Science and engineering Southeast University

The strength curves of lightweight aggregate concrete （LWAC） were tested based on detecting LWAC with density of 1 400-1 900 kg/m3 and LWAC with strength grade of LC15-LC50 by rebound method and ultrasonic-rebound combined *** results show that the common measured strength curves tested by above two methods can not satisfy the required accuracy of LWAC strength *** addition,specified compressive strength curves of testing LWAC by rebound method and ultrasonic-rebound combined method are obtained,respectively.

关键词： lightweight aggregate concrete compressive strength rebound method testing-strength curve ultrasonic-rebound combined method

Algebraic-Stress Turbulent Model of Planar 2-D Pollutant Transportation in Curvilinear Coordinates

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engineering Sciences 2005年第3期 70-74页

作者： Wu Xiuguang1, Huang Shichang1, Shen Yongming2, Y K Guo3(1. Zhejiang Institute of Hydraulics & Estuary, Hangzhou 310020 2. State Key Laboratory of Coastal and Offshore engineering, Dalian university of Technology, Dalian 116024 3. Department of engineering, university of aberdeen, aberdeen ab2. 3ue, uk)

The shallow-water equations and pollutant convective-diffusive equation are transformed into curvilinear coordinate system. The anisotropic algebraic-stress turbulent model is introduced to simulate the turbulence items, and algebraic-stress turbulent model of planar 2-D pollutant convective-diffusive in curvilinear coordinates is build. The meandering channel with measured data of concentration in lab is adopted to validate the model, and the distribution figure of pollutant concentration field calculated through this model and that of the k-ε model, which show the model is superior to k-ε turbulent model in dealing with anisotropy character of flow.

关键词： pollutant curvilinear coordinates anisotropic algebraic-stress turbulent model k-ε model

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3 1 Department of Earth Sciences, Durham university, Durham DH1 3LE, uk 2.school of Earth Sciences and Resources, China university of Geosciences, Beijing 100083, China 3 school of Earth and Space Sciences, Peking university, Beijing 100871, China Department of Earth Sciences Durham University Durham DH1 3LE UK school of Earth Sciences and Resources China University of Geosciences Beijing 100083 China school of Earth and Space Sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3) assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

Ultralight X-type lattice sandwich structure (Ⅱ):Micromechanics modeling and finite element analysis

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Science China(Technological Sciences) 2009年第9期52卷 2670-2680页

作者： ZHANG QianCheng1,CHEN AiPing 2,CHEN ChangQing2,3 & LU TianJian2 1 State Key Laboratory for Mechanical Behavior of Materials,school of Material Science and engineering,Xi’an Jiaotong university,Xi’an 710049,China 2 MOE Key Laboratory for Strength and Vibration,school of Aerospace,Xi’an Jiaotong university,Xi’an 710049,China 3 Department of engineering Mechanics,AML,Tsinghua university,Beijing 100084,China State Key Laboratory for Mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an China MOE Key Laboratory for Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an China Department of engineering Mechanics AML Tsinghua University Beijing China

The methods of homogenization and finite elements are employed to predict the effective elastic constants and stress-strain responses of a new type of lattice structure,the X-structure proposed by the authors in a companion paper. It is shown that in most cases the predictions by the equivalent homogenization theory agree well with the experimental and 3-dimensional finite element calculated results. The theoretical and numerical study supports the argument that the X-structure is superior to the pyramid lattice structure in terms of mechanical strength.

关键词： sandwich panel lattice structure equivalent homogenization finite element model

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2 with DNA and its analytical application

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Science China Chemistry 2010年第3期53卷 618-624页

作者： LIU JiangTao1,LIU ShaoPu2 & LIU ZhongFang2 1school of Chemistry,Chongqing Normal university,Chongqing 400300,China 2school of Chemistry and Chemical engineering,Southwest university,Chongqing 400715,China school of Chemistry Chongqing Normal University Chongqing China school of Chemistry and Chemical engineering Southwest University Chongqing China

The forming of bleomycinA2-Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2(BLMA2) can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2 with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2-Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2 was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2-Cu(Ⅱ) as RRS probe has been *** detection limits(3σ) are 7.2 ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching

Surface Topography of Fine-grained ZrO_2 Ceramic by Two-dimensional Ultrasonic Vibration Grinding

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Journal of Wuhan university of Technology(Materials Science) 2011年第6期26卷 1162-1165页

作者：丁爱玲 school of Mechanical and Automation engineering North University of China

The surface quality of fine-grained ZrO2 engineering ceramic were researched using 270# diamond wheel both with and without work-piece two-dimension ultrasonic vibration grinding（WTDUVG）. By AFM images, the surface topography and the micro structure of the two-dimensional ultrasonic vibration grinding ceramics were especially analyzed. The experimental results indicate that the surface roughness is related to grinding vibration mode and the material removal mechanism. Surface quality of WTDUVG is superior to that of conventional grinding, and it is easy for two-dimensional ultrasonic vibration grinding that material removal mechanism is ductile mode grinding.

关键词： two-dimension ultrasonic vibration grinding surface topography ductile grinding

On the general expressions of finite Hankel transform

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 College of Aerospace engineering,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,China 2.school of Civil engineering,Nantong university,Nantong 226019,China Nanjing university of Aeronautics and Astronautics College of Aerospace Engineering Nanjing China (GRID:grid.64938.30) (ISNI:***) Nantong university School of Civil Engineering Nantong China (GRID:grid.260483.b) (ISNI:***) Nanjing university of Aeronautics and Astronautics College of Aerospace Engineering Nanjing China (GRID:grid.64938.30) (ISNI:***)

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral

Classified real-time flood forecasting by coupling fuzzy clustering and neural network

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International Journal of Sediment Research 2010年第2期25卷 134-148页

作者： Minglei REN1, Bende WANG2, Qiuhua LIANG3, and Guangtao FU41 Dr., school of Civil & Hydraulic engineering, Dalian university of Technology, Dalian 116024, China 2 Prof., school of Civil & Hydraulic engineering, Dalian university of Technology, Dalian 116024, China 3 Lecture, school of Civil engineering and Geosciences, Newcastle university, Newcastle upon Tyne NE1 7RU, uk 4 Lecture, school of engineering, Computing and Mathematics, university of Exeter, Exeter EX4 4QF, uk Dr. School of Civil & Hydraulic Engineering Dalian University of Technology Dalian 116024 China Prof. School of Civil & Hydraulic Engineering Dalian University of Technology Dalian 116024 China Lecture School of Civil Engineering and Geosciences Newcastle University Newcastle upon Tyne NE1 7RU UK Lecture School of Engineering Computing and Mathematics University of Exeter Exeter EX4 4QF UK

This paper presented a new classified real-time flood forecasting framework by integrating a fuzzy clustering model and neural network with a conceptual hydrological model. A fuzzy clustering model was used to classify historical floods in terms of flood peak and runoff depth, and the conceptual hydrological model was calibrated for each class of floods. A back-propagation (BP) neural network was trained by using real-time rainfall data and outputs from the fuzzy clustering model. BP neural network provided a rapid on-line classification for real-time flood events. Based on the on-line classification, an appropriate parameter set of hydrological model was automatically chosen to produce real-time flood forecasting. Different parameter sets was continuously used in the flood forecasting process because of the changes of real-time rainfall data and on-line classification results. The proposed methodology was applied to a large catchment in Liaoning province, China. Results show that the classified framework provided a more accurate prediction than the traditional non-classified method. Furthermore, the effects of different index weights in fuzzy clustering were also discussed.

关键词： Real-time flood forecasting Flood classification Conceptual hydrological model Fuzzy clustering Neural networks