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Table of Content

    21 February 2009, Volume 15 Issue 1
    Mathematics.Physics and Chemistry
    Some Remarks on the Multiplicative Decomposition FFeFp in Finite Elasto-Plasticity
    SUN Bo-hua1,YE Zhi-ming2
    2009, 15(1):  1-7. 
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    Based on the work of Stumpf and Badur (1990) some problems related with the multiplicative decomposition FFeFp in finite elasto-plasticity have been investigated in detail. It is pointed out that there is no chance to supply an additional independent constitutive equation for plastic and/or elastoplastic spin since it can be represented, in general,by elastic and plastic stretches, as well as elastic and plastic deformation rates. It is especially for the case of rigid-finite plastic deformation suitable for metallic materials, the explicit representation of plastic spin, objective rate of back-stress and its relation with the Zaremba-Jaumann rate. Finally, a suitable way is pointed out that can supply an additional constitutive equation to plastic spin is the use of additive decomposition of elastoplastic deformation rates.

    Equivalence of Lp Projection Inequality and Lp Centroid Inequality
    YU Zhi-gang,YUAN Jun,LENG Gang-song
    2009, 15(1):  8-10. 
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    Petty’s projection inequality and Busemann-Petty centroid inequality are the basic inequalities in the classical Brunn-Minkowshi theory. In the recent studies, Lutwak, Yang and Zhang generalized the above two inequalities into the circumstances of Lp  Brunn-Minkowshi. The purpose of the present paper is to show equivalence of the Lp  Petty projection inequality and the Lp Busemann-Petty centroid inequality.

    Finite Groups with Every Non-abelian Subgroup Being Subnormal
    LUO Xiao-liang,GUO Xiu-yun
    2009, 15(1):  11-13. 
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    In this paper, the finite non-nilpotent group with every non-abelian subgroup being subnormal  is investigated.It’s shown that such groups are solvable, and then give a necessary and sufficient condition and some structures for this kind of groups by taking into account the Sylow subgroups. As an application, the supersolvable group with the above property is discussed.

    Distance between Unit Balls in lnp-Space and Its Application
    MA Dan,HE Bin-wu
    2009, 15(1):  14-16. 
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    The Banach-Mazur distance, defined by homothetic transformation, between two different unit balls in lnp-space is shown with optimization calculation. Compared to the Banach-Mazur distance, it shows distance between convex bodies without any rotation. The result is applied to estimate the Gaussian measure of unit balls in the lnp-space.

    Conditions for Two Types of Ellipsoids of Parallelotope Being Ball
    LIU Xu-fei,WANG Wei,LENG Gang-song
    2009, 15(1):  17-19. 
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    John ellipsoid and new ellipsoid are two types of important ellipsoids in convex bodies. In this paper, a necessary and sufficient condition for each of the two types of ellipsoids of the parallelotope being a ball is given.

    A Model of Growing and Navigating Networks
    DU Li-juan,SHI Ding-hua,CHEN Qian
    2009, 15(1):  20-25. 
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    There are three important structural features in complex networks: small-world effect, scale-free property and network’s navigability. Typical models reflecting these features, respectively, are the Watts-Strogatz’s model, the Barabási-Albert’s model and the Kleinberg’s model. Based on the typical models, a new model of growing and navigable networks is proposed, with the generated networks possessing all these features simultaneously. The results of navigation obtained by using a greedy algorithm on networks of the model are similar to, or even better than, that of the Kleinberg’s model.

    Mesh Free Difference Method Applied to Flows around 2-D Airfoil
    YE Zhi-qiang,LIU Gao-lian,CHEN Bo
    2009, 15(1):  26-31. 
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    According to the mesh-free method based on local Cartesian frame proposed by the author, partial derivatives at every node and natural boundary conditions are constructed by using the total directional derivative formulas. No mesh element is needed at all. Therefore it is very simple both theoretically and computationally. The method is tested with a numerical example of fluid flow. A reliable solution is obtained with high accuracy and efficiency.

    Optimization of Pumping Station with Simulated Annealing and Genetic Algorithm
    WEI Xin-hua,GUO Jia-hong
    2009, 15(1):  32-36. 
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    To cope with the problem of low efficiency of pump station due to unreasonable combination of the pumps, a mathematic model for optimizing the combination is proposed leading to minimal power consumption. The constraining conditions in the model are the pump head, total water supply and rotation speed of the pumps. A simulated annealinggenetic algorithm is used to determine the number of pumps in operation, the rotation speed and the flow rate of each pump when the pump station is in an optimal state. The infeasibility degree is introduced into the algorithm to choose a suitable result from every population and to balance the demand between the target function and the constraining conditions. The result of an example shows feasibility of the present algorithm for pump station optimization.

    Deviation of Light Path in Born-regulated Gravity in Four Dimension
    ZHOU Jian-hua,FANG Wei,LU Hui-qing
    2009, 15(1):  37-41. 
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    Deviation of light from its straight path is caused by the presence of massive objects, i.e., the presence of gravitational field according to the general theory of relativity. It is shown that the low energy effective field theory on D-branes is of Born-regulated gravity theories. In this work a Born-regulated type gravitational field is postulated. According to the space time metric in the Born-regulated gravity theory, An explicit representation of the angular deviation of light path is derived. A Born-regulated type theory of gravitational field is postulated, and an explicit representation of the angular deviation of light path is derived, Δφ≈4Mrmin-4Mrmin49k2βr6min. Clearly, the result shows that β→0 and k→0, Δφ→4Mrmin which is just the result from the Einstein’s general relativity theory.

    Communication and Information Engineering
    Mixed-Signal SoC Verification Using NanoSim-VCS
    HU Yue-li,JING Wen-yi,XUAN Xiang-guang
    2009, 15(1):  42-46. 
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    Complex full-chip system verification and interface nodes analysis between analog and digital circuit are a bottle-neck in mixed-signal system design. In this paper, a mixed-signal verification method based on NanoSimVCS is proposed, which is used to verify SHU-MV06, a mixed-signal design including Verilog and SPICE. This method provides efficient simulation with high accuracy and speed by performing speed-versus-accuracy tradeoffs. Defects can be found in time at an early stage and the design quality can be improved significantly.

    Moving Object Capture Based on Characteristics of APS-CMOS Image Sensor
    LI Wei,PAN Zhi-hao,WANG Min
    2009, 15(1):  47-50. 
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    With the growing requirement of moving object capture in embedded systems, it is hard to tradeoff the conflict requirements of resolution and capture speed. The proposed method splits motion capture process into motion detection and target capture, which have different emphases on resolution and speed. Using an active-pixel architecture, CMOS image sensor’s hardware characteristics can randomly access the sensor’s image buffer to achieve the switch between working modes of varying trait on the digital signal processing (DSP) platform. Thus, both capture speed and resolution can be guaranteed. With the proposed method, ordinary chips can achieve better performances, which otherwise would require higher performance chips.

    Low-Sidelobe Microstrip Array with Circular Polarization for Radio Frequency Identification Applications
    SUN Zhu,ZHONG Shun-shi,CHEN Kuang-da,TANG Xiao-rong
    2009, 15(1):  51-53. 
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    The design of a microstrip antenna array for 2.45 GHz radio frequency identification (RFID) reader applications is introduced with measured results. The array is of simple structure, low sidelobe level and circular polarization characteristics. Its measured sidelobe level is -23.2 dB, and the measured VSWR≤2 impedance bandwidth is 130 MHz (from 2.44 GHz to 2.58 GHz), making it suitable for RFID applications.

    Spectrum Sensing in Cognitive Radio Based on Energy Detection
    PAN Jian-guo,ZHAI Xu-ping
    2009, 15(1):  54-59. 
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     Cognitive radio (CR) is viewed as a novel approach for improving utilization of the precious radio spectrum. This paper first reviews the background and concepts of CR, and then investigates energydetection based spectrum sensing by focusing on the spectrum sensing function. To deal with the problem of local sensing characteristic in wireless signal detections in the energy detection process, a distributed M-cooperative detection scheme is presented. Analytical detection probability based on the “OR” rule is presented. Both simulation and the analytical results indicate that, with a small tradeoff between detection probability and false alarm probability, the scheme significantly improves the spectrum sensing ability under low SNR.

    Computer Engineering and Science
    n Approach to Generating Integration Test Case Based on Object-Z Specification
    ZHU Yi-yi1,MIAO Huai-kou1,2,TANG Xin-xiang1
    2009, 15(1):  60-65. 
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    Formal methods have precise description and high-level abstraction capability. Written specification in a formal method avoids consideration of data structures and algorithms in detail at the demand analysis stage. Meanwhile, it can reduce uncertainty and ambiguity in system modeling. This paper proposes a method for describing component models by using Object-Z schema and criteria to generate test a scenario, generating test cases for integrated testing on component systems.

    Computation of Lattice Boltzmann Method Based on Graphics Processing Unit
    FENG Wei-bing,YANG Xiao-ling
    2009, 15(1):  66-70. 
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    Computation based on graphics processing unit (GPU) has attracted increasing attention as a new research direction. As an introduction to the high performance of GPU, this paper first analyzes features of GPU as reported in the literature published in the recent years. Computation model of GPU is introduced, and pipeline structure analyzed. Programming on GPU is then discussed. Computation of lattice Boltzmann method (LBM) on GPU is implemented.

    Demand Forecast Using Support Vector Machine for a Product Category
    GAO Jun-jun1,TAN Chong-li1,LIU Yue2,YIN Ya-feng2
    2009, 15(1):  71-76. 
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    Demand forecast is the basis of business operation for a company. Forecast accuracy has a great effect on safety inventory, profit and competitiveness. In this paper, support vector machine (SVM) is used to forecast the demand of a product category including multiple brands. Various factors that affect the product demand such as seasonal and promotional factors are taken into consideration. Data used in model training and assessment are generated from the demand function of this product. Different forecast models such as regression model, double exponent smooth model, Winter model and radial basis function neural network model are used for comparison and evaluation. The results show that accuracy of SVM is superior to other models, which can significantly reduce the inventory level. Therefore SVM is shown to be an effective model for demand forecast.

    Distributed Resource Scheduling System Based on Reliability
    XU Wei-min,CAI Xin-huan,SHEN Wen-feng,ZHI Feng-lin
    2009, 15(1):  77-80. 
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    The management of resources and task scheduling in a distributed computing is complex and challenging due to various factors such as the resource’s geographic distribution, heterogeneity, dynamic, distributed ownership with different policies and priorities, varying loads, reliability, and availability conditions. Performance measurement, analysis and prediction of distributed systems have become increasingly important. In particular, accurate load prediction of each computer is crucial in achieving required performance for practical applications. This paper presents a resource schedule algorithm based on its reliability, which is the centre of any scheduling and resource allocation algorithm. The algorithm can effectively resolve the problem of load balancing in a distributed system.

    Mechatronics Engineering and Automation
    Interruptible Load Management Considering Reliability of Consumers
    LIU Guo-chun,ZHANG Shao-hua,WANG Xian
    2009, 15(1):  81-86. 
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    One way of operating a power network economically and safely is to implement interruptible load (IL) management. IL is an important measure which can ascertain the power outage cost. By considering the reliability indexes such as interruption duration, a new power outage cost function is constructed. A model of interruptible load management based on the function which takes into account consumer reliability is studied. Several case studies are carried out to show that using the model can improve benefit per unit of energy.

    Material Science
    Preparation and Characterization of Graphite/nano-ZrO2 Composite Powders
    LIU Jian-fei1,2 ,HANG Jian-zhong3,SHI Li-yi1,ZHU Wei-de2
    2009, 15(1):  87-92. 
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     Graphite/nanosized ZrO2 (GN ZrO2) composite powder was successfully prepared, with ZrOCl2·8H2O being predecessor, by surface modification on the natural flaky graphite particles using a heterogeneous nucleation technique. The effect of the amount of ZrO2 on hydrophilicity of the composite powders was investigated. Hydrophilicity of GN ZrO2 composite powders being modified was greatly improved. Composite powders were characterized by Zeta potential testing instrument and TGA-DSC analytical apparatus respectively. Isoelectric points of composite powder varied from pH=2.5 to pH=5.3 and the antioxidation property improved to some degree because the oxidation gravimetric ratio decreased from 98.9% to 93.1%. In addition, SEM photographs and the EDS analysis indicated that the graphite surface was coated with a layer of dense nano-sized ZrO2 particles, whose size was dozens of nanometers. XPS results showed that the surface of graphite powders exhibited Zr characteristic peak and the electron binding energy of C1s shifted by 0.4 eV toward the higher side.

    Civil Engineering
    Experimental Study on Freezing Expansion and Water Transference of Shanghai’s Artificially Frozen Soil
    QIN Ai-fang1,2,LIN Jin-qian1,2,PU Yi-bin2,GU Tong-xin2,XING Li-li2
    2009, 15(1):  93-98. 
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    Freezing expansion is the most prominent character of frozen soil, which can bring displacement of ground and therefore is harmful to the surrounding areas. By testing Shanghai’s frozen clay with different frozen quantities and frozen stresses, the relations of consolidated stress are obtained with frozen quantity and frozen stress, and instance of water transference in the frozen process is the results of this study is useful in the design and construction of artificially frozen soil project of Shanghai.

    Experiments on Compression Characteristics of Remoulded Soft Clay in Shanghai
    ZHOU Ke,SUN De-an
    2009, 15(1):  99-104. 
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    Differences in compression index (Cc) and swelling index (Cs) of remoulded soft clay in Shanghai measured by different test methods are studied. The tests include isotropic compression test, K0 test and one-dimensional compression test. Differences in compression index are compared based on the results of three isotropic compression tests, two K0 tests, and three one-dimensional compression tests. And differences in swelling index are also compared based on the results of one-dimensional compression tests and isotropic compression-unloading-and-reloading tests. Variation in K0 due to the change of σv is identified from K0 tests, and the relationship between K0 and over consolidation ratio (OCR) is also given. The relationship between Cs and OCR is studied using the results of the three different kinds of tests. Results of these tests are a basis of construction of constitutive models of remoulded soft clay in Shanghai.

    Test of Strengthening Negative Moment Area of Reinforced Concrete Continuous Beams with Carbon Fiber Reinforced Polymer
    YE Hong-yi1,CHEN Yong-xiu2
    2009, 15(1):  105-110. 
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    When strengthening the negative moment area of a reinforced concrete (RC) beam, the presented anchorage would be insufficient because the carbon fiber reinforced polymer (CFRP) strips will be cut-off at the place of column. For this reason, strengthening effectiveness of several bonding methods is discussed in this paper based on tests. The supports of continuous beam of the vertical axis from different parts of the carbon fiber strain changes has been studied. By inspection of wing plates in different parts of the CFRP structural capacity increase of the contribution of difference, useful conclusions are obtained.