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New concurrent digital signature scheme based on the computational Diffie-Hellman problem

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The Journal of china Universities of Posts and Telecommunications 2010年第6期17卷 89-94,100页

作者： QIN Wen,ZHOU Nan-run department of Electronic Information engineering,{2. university,{2. 330031,china department of Electronic Information engineering Nanchang University Nanchang 330031 China

Based on strong designated verifiers signatures,a new fair concurrent signature scheme is proposed. Compared with the previous concurrent signature schemes,even if a keystone must be chosen by the initial signer,the matching signer will easily get the keystone through an extraction algorithm. Due to the property of strong designate verifying,the initial signer couldn＇t make use of the keystone prepared carefully to deceive the matching signer. Then the matching signer is able to participate actively the signature scheme. Besides,there aren＇t bilinear operations in the keystone algorithm to deliver the keystone efficiently. Therefore the efficiency of our signature scheme is also improved.

关键词： designated verifiers signature fairness concurrent signature information security

A NEW TURBULENCE MODULATION IN SECOND-ORDER MOMENT TWO-PHASE MODEL AND ITS APPLICATION TO HORIZONTAL CHANNEL

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Journal of Hydrodynamics 2008年第3期20卷 331-338页

作者： ZENG Zhuo-xiong Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China

A new second-order moment two- phase turbulence model accounting for particle wake effect was established and used to simulate gas-particle flow in a horizontal channel for different values of wall roughness. The results show that compared with the model without considering the particle wake effect, the present model gives simulation results agreeing much better with the experimental results for the gas turbulence modulation, but the predicted results for particle motion with the two kinds of models are quite close.

关键词： gas-particle flows turbulence modification numerical simulation

SECOND-ORDER MOMENT TWO-PHASE TURBULENCE MODEL ACCOUNTING FOR TURBULENCE MODULATION IN SWIRLING SUDDEN-EXPANSION CHAMBER

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Journal of Hydrodynamics 2008年第1期20卷 54-59页

作者： ZENG Zhuo-xiong Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China

A semi-empirical turbulence enhancement model accounting for the particle-wake effect was incorporated into the second-order moment two-phase turbulence model and employed to simulate gas-particle flows in a swirling sudden-expansion chamber. The simulated results for two-phases mean velocities and fluctuation velocities coincide well with the experiment ones, which demonstrates that this model, in comparison with the turbulence model not accounting for the wake effect, leads to higher calculating accuracy.

关键词： gas-particle flows turbulence modulation particle wake effect

A SECOND-ORDER MOMENT TURBULENCE MODEL FOR POWER LAW FLUID WITH PARTICLES

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Journal of Hydrodynamics 2007年第5期19卷 607-612页

作者： ZENG Zhuo-xiong PAN Yang ZHONG Chun QIU Guo-bin Aeronautic and mechanical engineering College Nanchang Hangkong University Nanchang 330063 China School of Civil engineering and Architecture East China Jiaotong University Nanchang 330013 China

The USM-θ model of power law fluid for dense two-phase turbulent flow was developed, which combines the unified second-order moment model for two-phase turbulence with the particle kinetic theory for the inter-particle collision. This model was used to simulate the turbulent flow of power law fluid single-phase in pipe. It is shown that the USM- θ model has better prediction result than the κf -κf - κ- εp -θ model. The USM-O model was then used to simulate the dense two-phase turbulent up flow of power law fluid with particles. With the increase of the flow exponent, the velocities of power law fluid and particles increase near the pipe centre. Comparison between the two-phase flow of power law fluid-particle and of liquid-particle indicates that the axial fluctuation velocity of fluid phase and particle phase in liquid-particle two-phase flow is smaller than that in the power law fluid two-phase flow, but the two-phase velocities of power law fluid-particle and liquid-particle are close to each other.

关键词： power law fluid two-phase flow second-ordermoment turbulence model

Effect of static magnetic field on activity of immobilized α-amylase

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Chinese Science Bulletin 1997年第2期42卷 127-130页

作者： YAN Liushui, ZHU Yuanbao, HE-Shuang’e and CAO Zhixiang1 department of Chemical engineering, {2. Institute of Aeronautical Technology, {2. 330034, china 2. department of Chemistry and Chemical engineering, Hunan university, Changsha 410082. china department of Chemical engineering Nanchang Institute of Aenwututical Techndogy Nanchang China department of Chemistry and Chemical engineering Hunan University Changsha China

BIOLOGICAL effect of magnetic field is one of the three major subjects of contemporary biomagnetism, and is also the basis of applied biomagnetism. In order to explore magnetic biological effects, the influence of various sorts of magnetic field on many living systems as well as their different constructural levels has been extensively studied. However, only a few studies with in vitro enzyme have been reported, and few researches concerning the influence of magnetic field on immobilized enzyme reactions have been published. This note describes

关键词： static magnetic field immobilized α-amylase enzyme activity oscillatory behaviour.

CONTACT FRICTION ANALYSIS AND STRESS OSCILLATION SUPPRESSION WITH A SIMPLE INTERFACE ELEMENT

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Acta Mechanica Solida Sinica 2000年第1期13卷 33-41页

作者： Lei Xiaoyan (department of Civil engineering,East{2. Jiaotong university,nanchang 330013,china) department of Civil engineering East China Jiaotong University Nanchang 330013 China

A simple interface element for analyzing contact friction problems is developed. Taking nodal displacements and contact stresses as unknowns, this element can simulate frictional slippage, decoupling and re-bonding of two bodies initially mating or having gaps at a common interface. The method is based on the Finite Element Method and load incremental theory. The geometric and static constraint conditions on contact surfaces are treated as additional conditions and are included in stiffness equations. This simple element has the advantages of easy implementation into standard finite element programs and fast speed for convergence as well as high accuracy for stress distribution in interface. Undesirable stress oscillations are also investigated whenever large stress gradients exist over the contact surfaces. Exact integration or the conventional Gauss integration scheme used to evaluate the interpolation function matrix of the interface element is found to be the source of the oscillations. Eigenmode analysis demonstrates that the stress behavior of an interface element can be improved by using the Newton-Cotes integration scheme. Finally, the test example of a strip footing problem is presented.

关键词： contact friction interface element stress oscillation eigenmode analysis

A TWO-SCALE SECOND-ORDER MOMENT PARTICLE TURBULENCE MODEL FOR GAS-PARTICLE FLOW

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Journal of Hydrodynamics 2006年第6期18卷 659-665页

作者： ZENG Zhuo-xiong ZHOU Li-xing department of engineering Mechanics Tsinghua University Beijing 100084 China department of mechanical {2. Nanchang Institute of Aeronautical Technology Nanchang 330034China

A two-scale second-order moment two-phase turbulence model was developed and used to simulate gas-particle flow in a sudden-expansion chamber and a channel. The simulation results were in agreement with the experimental results, and the results were compared with those of the single-scale second-order moment two-phase turbulence model. Several improved features show that the two-scale model is to a certain extent better than the single-scale model, which may be attributed to the fact that particle turbulence is well characterized by the two-scale turbulence model.

关键词： gas-particle flow second-order moment model,two-scale fluctuation

Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural Science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1,2. Meng Fei~1 Wang Yijun~1 Gao Xiaorong~1 Gao Shangkai~(1**) (1.department of Biomedical engineering,School of Medicine,Tsinghua {2.,Beijing 100084,china 2.department of Electronic engineering,School of Information,nanchang {2.,nanchang 3.0029,china) department of Biomedical engineering School of Medicine Tsinghua University Beijing 100084 China department of Electronic engineering School of Information Nanchang University Nanchang 330029 China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discriminating different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91% on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

Phosphorus forms and distribution in the sediments of Poyang Lake,china

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International Journal of Sediment Research 2011年第2期26卷 230-238页

作者： XIANG Su-lin and ZHOU Wen-bin 1 Lecturer,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,china and department of Environmental engineering,East china JiaoTong university,nanchang 330013,china, 2.Prof,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,china Lecturer Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China and Department of Environmental Engineering East China JiaoTong University Nanchang 330013 China Prof. Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China

The forms and distribution of phosphorus in the sediments of Poyang Lake were studied using chemical extraction methods to understand the potential release and adsorption of *** results showed that phosphorus in the sediments mainly consisted of inorganic phosphorous species, including iron bound phosphorus,calcium bound phosphorus,aluminium bound phosphorus and dissolved phosphorus,as well as organic phosphorous *** spatial distribution of phosphorus species in surface sediments showed a decreasing trend from the outlet to the entrance of Poyang *** content of total phosphorus in the surface sediments ranged from 688.2. to 82..36 mg/kg, and inorganic phosphorous was the major phosphorus *** bound phosphorus was the dominant form of inorganic phosphorous,accounting for greater than 40%of the total phosphorus, while calcium bound phosphorus and aluminium bound phosphorus accounted for more than 2.%, and dissolved phosphorus accounted for less than 5%.The content of organic phosphorus in surface sediments was lower,accounting for less than 15%.Total phosphorus was positively correlated with iron bound phosphorus,aluminium bound phosphorus,calcium bound phosphorus and organic phosphorous,while organic phosphorous was positively correlated with iron bound phosphorus and aluminium bound phosphorus,but only weakly related to calcium bound *** all six sites, the contents of total phosphorus and phosphorus forms in the core sediments obviously decreased with depth,while they were significantly enriched in the surface *** total phosphorus and phosphorus forms contents were significantly higher in the upper layers and had a tendency to decrease toward the bottom of the core,regardless of the phosphorus *** addition,the average contents of total phosphorus and various phosphorus forms decreased rapidly with sediment depth from 0-2. cm,and then decreased slightly from 2.-30 cm.

关键词： Poyang Lake Phosphorus forms Distribution characteristics Sediment