Volume 34,Issue 10,2011 Table of Contents

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  • 1  Open-electrical impedance tomography with variation regularization algorithm
    HUANG Song HE Wei LUO Ci yong
    2011, 34(10):1-7. DOI: 10.11835/j.issn.1000-582X.2011.10.001
    [Abstract](1903) [HTML](0) [PDF 10.50 M](2633)
    Abstract:
    Open electrical impedance tomography (OEIT) with fixed electrode row is proposed to overcome the clinical application problems in closed electrical impedance tomography such as poor model adaptability, electrode position error, and inflexibility. Variation regularization algorithm (VRA) using variations function as regularization penalty term is proposed to save the more serious ill-posed inverse problem of OEIT. Simulation and experiment results show that the inverse problem of OEIT can be efficiently solved by VRA. The position, size and the relative value of conductivity of target at shallower position below electrodes can be clearly reflected by the restored image. OEIT is more potentially practical and effective in clinical applications.
    2  Dynamic scheduling method of vehicle air-conditioning assembly shop based on feedback control
    YIN Chao LI Tao LIU Fei YIN Sheng
    2011, 34(10):8-14. DOI: 10.11835/j.issn.1000-582X.2011.10.002
    [Abstract](1662) [HTML](0) [PDF 8.23 M](1120)
    Abstract:
    By analyzing the inherent uncertainties, discrete uncertainties and external environmental uncertainties, a dual-feedback control strategy and the dynamic scheduling method are proposed to solve the dynamic scheduling problem of vehicle air-conditioning assembly shop under uncertainty. Considering the reentrant constraint, equipment capacity constraint, and time discrete constraint etc., the multi-objective scheduling model of vehicle air-conditioning assembly shop is set up,taken the earliness/tardiness, process time, production cost and quality loss as optimization objectives. According to the characteristic of the model, sectional chromosome encoding, crossover operator and mutation operator are designed to prevent the generation of illegal solutions and improve efficiency of the algorithm. An example is given to prove the feasibility and validity of the approach.
    3  Hilbert-Huang transform and denoising for partial discharge ultrsonic singals of large motor
    CHEN Xue jun YANG Yong ming WANG Quan di
    2011, 34(10):15-20. DOI: 10.11835/j.issn.1000-582X.2011.10.003
    [Abstract](1927) [HTML](0) [PDF 7.48 M](1040)
    Abstract:
    Empirical mode decomposition (EMD) algorithm is introduded as the core of the Hilbert-huang transform (HHT), and implementation process of EMD is analyzed. Then data compression denoising algorithm based on EMD is proposed, simulation and experimental signals are used for verification of the effect of EMD. In the same data sources, the comparison of data compression denoising approaches based on the EMD, db2 wavelet and db8 wavelet are conducted. In addition, physical experiment of the same analysis and comparisons are conducted on a running motor in a Chongqing electrical plant. Simulation and experimental results show that data compression denoising algorithm based on EMD can achieve the same denoising effect, or even better than based on db2 wavelet, db8 wavelet. The former is more perfect than the latter in the real signal processing, and denoising based on EMD is not loss of the original signal energy.
    4  Single-point preview control for unmanned high-speed4WID-4WIS vehicle path tracking
    RUAN Jiu hong LI Yi bin YANG Fu guang RONG Xue wen
    2011, 34(10):21-26. DOI: 10.11835/j.issn.1000-582X.2011.10.004
    [Abstract](4103) [HTML](0) [PDF 7.13 M](2023)
    Abstract:
    As for the actuation redundancy, strong nonlinearity and uncertainty, a kind of single-point preview control approach for the unmanned high-speed four-wheel-independent-drive & steering (4WID-4WIS) vehicle path tracking is proposed based on the control allocation and the Active Disturbance Rejection Control(ADRC) methods. The vehicle single-point preview system dynamic model for path tracking is built. The control system architecture with the control allocation unit as the core is constructed. The decouple single-point preview ADRC controller for path tracking is designed. Then the quasi-inertial parts used to generate control objectives are proposed and its rationality is discussed. The control allocation solution method for the 4WID-4WIS vehicle path tracking is subsequently presented. The simulations are conducted to illustrate the validity of the single-point preview control method proposed. The results show that the unmanned high-speed 4WID-4WIS vehicle can track the circular arc double-lane change path rapidly and accurately.
    5  Analysis of a multimode transmission line model of the shielding effectiveness of enclosures with apertures
    LI Yong ming ZHENG Chun xu HAO Zhan duo LIU Guang ming
    2011, 34(10):27-31. DOI: 10.11835/j.issn.1000-582X.2011.10.005
    [Abstract](1971) [HTML](0) [PDF 5.66 M](1026)
    Abstract:
    The equivalent transmission line method is extended to multi-transverse electric modes of cavity which are introduced by aperture coupling, and it is used to analyze the shielding effectiveness of rectangular enclosures with apertures. The multimode transmission line method is verified by HFSS(High Frequency Structure Simulator). The results show that higher-order mode is essential to obtain an accurate shielding effectiveness of rectangular enclosure on wide frequency domain. Below the frequency of 1 GHz, nearer to the slot, the impact of higher-order mode on the shielding effectiveness is greater in the place mear the slot. Higher-order mode leads to a better shielding effectiveness.
    6  Gear classification and coding system oriented to product standardization
    CHEN Bing kui XIE Fa xiang WANG Zhen rong
    2011, 34(10):32-38. DOI: 10.11835/j.issn.1000-582X.2011.10.006
    [Abstract](1590) [HTML](0) [PDF 9.22 M](1243)
    Abstract:
    A 28-code gear classification and coding system based on the similarity principle of the Group Technology is set up and key technical characteristics of gear products are obtained. Then the geometrically and technically similar part families are clustered through analyzing the results of gear classification and coding, which lead to the formation of gear product standards. Through combining the core features of gear products with rolling bearing identification code sequence,a 11-product-identification-code system is designed and implemented in one special gear manufacturer enterprise.By employing Visual Basic6.0 and SQL Server2000,a Computer Aided Gear Classification and Coding System oriented to Client/Server was developed and exemplified by one specific case. Application results show that the system effectively groups gear products and efficiently categorize the technical characteristics of those having the same classification code into narrower classes,which propell the standardization of gear design and its production.The situation in which various gears are produced in small batches respectively will be improved by large batch production and finally the professional model of mass-customization production will be realized.
    7  Violent-slide rock avalanche and excitation effect of perilous rock
    TANG Hong mei WANG Zhi XIAN Xue fu CHEN Hong kai
    2011, 34(10):39-45. DOI: 10.11835/j.issn.1000-582X.2011.10.007
    [Abstract](1824) [HTML](0) [PDF 8.19 M](1256)
    Abstract:
    The physical model of perilous rock avalanche excitation effect is deudofed based on the effect of the main factors, such as weight and fissure water pressure. It quantizes the interaction of perilous rock masses through the energy point of fracture mechanics and wave theory, and gains the departure rate formula of landslide body at momentary avalanche. The particle displacement rate calculation method of perilous rock medium under the action of excitation waves is developed based on the formation of perilous rock avalanche excitation waves and the spread mechanism in slope rock formation. The example shows that the analysis results established are coincident with actual situation. Some scientific basis is provided for the further research of perilous rock damage and evolutionary mechanisms.
    8  Application of multivariate statistics in model experimental analysis of air cushion towing of 4-suction anchor platform
    LE Cong huana DING Hong yan DONG Guo hai
    2011, 34(10):46-53. DOI: 10.11835/j.issn.1000-582X.2011.10.008
    [Abstract](1474) [HTML](0) [PDF 8.52 M](1003)
    Abstract:
    This paper coducts model tests on a 1∶20 scaled model of four-suction anchor platform. The acceleration, the internal air pressure, the bottom water pressure of the suction anchors and towing force of the suction anchor platform are determined in series of towing combinations with different wave direction, wave velocity, wave period, towing velocity, towing points, towline length and tilt angle. Cluster analyses are used to classify the combinations of towing and factor analyses one used to analyze the mechanical characters. The correlative matrix is obtained which can reflect the correlation of mechanical characters. The factor analysis results show that 85% the total variance is attributed to the former six factors, and the factor scores of the towing combinations was obtained to find the most disadvantageous combinations and the mechanical characters which can lead to the disadvantageous results. The analysis results can be used for consulting the practical application.
    9  Driver perception reaction time under the emergency evacuation situation
    XU Zhi YANG Xiao kuan ZHAO Xiao hua LI Ling jie CHEN Xin yue
    2011, 34(10):54-60. DOI: 10.11835/j.issn.1000-582X.2011.10.009
    [Abstract](1820) [HTML](0) [PDF 7.40 M](1307)
    Abstract:
    The way of scenario simulation is used to create a driving environment in the emergency evacuation and the questionnaire investigation. The Miriam ECG are used to verify the validity of the driving environment in the emergency evacuation from subjective and objective aspects. Based on the SimWorld driving simulator, the research is conducted on three kinds of Perception Reaction Time (PRT) under both normal situation and the emergency evacuation situation: the PRT under the sudden situation, the PRT during acceleration and the PRT during deceleration.
    10  Job-Shop scheduling based on improved immune cloning algorithm
    LIU Ai jun YANG Yu XING Qing song YAO Hao ZHANG Yu dong ZHOU Zhen yu
    2011, 34(10):61-67. DOI: 10.11835/j.issn.1000-582X.2011.10.010
    [Abstract](1757) [HTML](0) [PDF 8.08 M](1124)
    Abstract:
    Parallel immune clone algorithm is proposed based on population coevolution theory and parallel computing affinity of individual at multiple compute nodes. Introducing the immune memory mechanism, the evolution processes of antibody population and memory units are conducted simultaneously, meanwhile, it improves mutual cooperation among antibodies, and ensures solution set approaching optimal solution from the inside of feasible region or infeasible region border. Clone proliferation, high frequency variation and operation of crossover operators increase the chance that better individuals gain affinity maturation by the operation of clone expansion, improve diversity of antibody population distribution, achieve the balance of optimization between depth and range, and ensure the convergence of the algorithm and the diversity of the search range. A computational study for a standard data set is carried out to test the validity of the algorithm, and the effect of algorithm parameters on the results is analyzed. The simulation results show that the global search capability, local search capability, algorithm stability and computing speed of the algorithm are all superior to conventional optimization algorithms such as normal immune clone optimization algorithm, genetic algorithm, etc.
    11  Normalized inelastic deformation ratio spectra
    Tong Gen shu Cai Zhi heng ZHANG Lei
    2011, 34(10):68-75. DOI: 10.11835/j.issn.1000-582X.2011.10.011
    [Abstract](1717) [HTML](0) [PDF 11.80 M](1719)
    Abstract:
    This paper analyzed seismic response of SDOF elastic-perfectly plastic (EPP) hysteretic systems considering P-Δ effect. It used totally 370 earthquake records belonging to four site and soil conditions to calculate the inelastic deformation ratios (Cd) with different ductility, and used the characteristic periods Tga and TgR to normalize the Cd spectra to keep the valley spectral values at these two periods. Results indicate that both P-Δ effect and damping ratio have significant effects on Cd , especially nearby the characteristic periods.
    12  The equivalent enthalpy drop theory calculation of the ejector heaters applied for low-pressure feed water heater system of thermal power unit
    YANG Lin RAN Jing yu
    2011, 34(10):76-81. DOI: 10.11835/j.issn.1000-582X.2011.10.012
    [Abstract](1777) [HTML](0) [PDF 5.58 M](998)
    Abstract:
    There is much exergy loss in low-pressure feed water heater system of the thermal unit. The thermo-economic characters by the equivalent enthalpy drop method while the low-pressure heater was replaced with the ejector heater. At the same time, the thermo-economic characters formulas for the different factors were also gotten. Based on these results, the thermo-economic changing features were analyzed for the low pressure heaters replaced with the ejector heaters of the N600-165/535/535 units, and the results were compared with the normal heat balance method. The results show that the ejector heaters can reduce the exergy loss efficiently, and the thermo-economic effects is the best for replacing the all low-pressure heaters with the ejector heaters, and its efficiency can be increased by 0.263%. The given equations of this paper can be used for analyzing the thermal economic effects.
    13  Study on heat transfer characteristics in a gasification convective syngas cooler
    YANG Zhen ZHAO Zhen xing GUO Qin qin LIU Hong CAO Zi dong
    2011, 34(10):82-85. DOI: 10.11835/j.issn.1000-582X.2011.10.013
    [Abstract](1701) [HTML](0) [PDF 5.80 M](1122)
    Abstract:
    This study uses high pressure single gas (He and N2) and mixture(He + N2) gas instead of the high pressure syngas , and the test pressure for each gas were from 0.5 MPa to 3 MPa with test temperature from 150 ℃ to 450 ℃. The results show that the working pressure, gas composition and flow heating methods influence the high pressure gas convective heat transfer coefficient, and the effect of the working pressure is the most prominent. The average convection heat transfer coefficients are obtained for different kinds of high pressure gas in annular channel heat exchanger, and the correlations of the typical flow heating methods and its applicable condition.
    14  Analyses of earthquake-induced landslide inventory in Yingxiu meizoseismal area of 5.12 Wenchuan earthquake
    LIU Xin rong HU Yuan xin GE Hua Qi Da he
    2011, 34(10):86-96. DOI: 10.11835/j.issn.1000-582X.2011.10.014
    [Abstract](2055) [HTML](0) [PDF 15.03 M](2197)
    Abstract:
    A number of landslides were triggered by the Wenchuan earthquake on May 12 2008. The damage caused by these landslides was even more than that by earthquake. Systematic landslides inventory, as a basic technique for landslide study, can provide applicable data to quantify the study of landslides. A lot of earthquake-induced landslides were concentrated in Yingxiu meizoseismal area of 5.12 Wenchuan Earthquake. By means of post-earthquake aerial photo and satellite imagery interpretation and field investigation, this paper gets the information including locations, types and morphometry about 1948 earthquake-induced landslides within the Yingxiu Meizoseismal area (about 109.3 ㎞ 2) and inventoried them with GIS software. Then, overlay analyses are used between these landslides inventory data and environmental factors such as slope aspect, slope angle, distance from ridge, geologic units and lithology, distance from epicentre and seismogenic fault. The results show that: Landslides are triggered by earthquake scatter predominantly in the range of 30°~50°, and the landslide density is positively correlated with slope angle. Areas nearby ridge are of high landslide density indicating that amplification effect of ridge on seismic wave is an important reason of slope failure. Earthquake-induced landslide development level in Pengguan complex is higher than that in sedimentary petrologic province. Landslide density is the single exponential negative correlation with distance from epicentre and seismogenic fault indicating that earthquake-induced landslide development level in hanging wall of seismogenic fault is higher than that in footwall, and the results predicted by regression correlation agree with the existing research findings.
    15  Theoretical analysis and experimental study on the effect of the different components of porous medium gypsum on porosity
    TONG Ming wei WU Zhong zheng HU Peng LIU Bin
    2011, 34(10):97-102. DOI: 10.11835/j.issn.1000-582X.2011.10.015
    [Abstract](2121) [HTML](0) [PDF 6.12 M](1226)
    Abstract:
    This paper uses a variety ways to prepare the gypsum(CaSO4·2H2O) and measured its physical properties, including vertical suction height h, the water velocity u in the horizontal state, the porosity η and the average pore radius. The results show that the way of preparation of the porous medium gypsum has great relationship with its properties. The gypsum is formed by adding some proper water into the CaSO4 , and its porosity is increasing with the increase of the water, but the strength is decreasing. Adding a bit of potassium citrate in the water can improve the performance of the gypsum , and the vertical suction height, the water’s horizontal velocity and the porosity can reach 120 cm, 4.2 mm/min and 69.4% respectively, so the gypsum can be used as the filling materials of the capillary suction liquid core radiator.
    16  Time-variation full process mode of steel bar corrosion in concrete
    JIANG Jian hua YUAN Ying shu PENG Tao
    2011, 34(10):103-108. DOI: 10.11835/j.issn.1000-582X.2011.10.016
    [Abstract](1541) [HTML](0) [PDF 7.29 M](1342)
    Abstract:
    This paper discusses the corrosion rate variation of reinforcing steels in concrete in constant climate environment. The corrosion current density of steel bar in concrete under a constant climate environmental condition and chloride attack. The results indicate that the corrosion rate (corrosion current density) of the steel bars is time-dependent during a corrosion process, and the time-dependent process can be divided into six phases in the full lifetime. The results also show that the effects of the concrete strength and the electrical resistivity of the concrete on the variation of the corrosion rate. This study conducts the mechanism analyses about the test results based on the microstructure of the interfacial transition zone (ITZ) between the steel bars and the concrete at different corrosion levels. The growth of the corrosion layer and the corrosion cracking are the main factors influencing the corrosion process. The time-variation mode of the corrosion rate of steel bars in full process is developed.
    17  A fuzzy logic multicasting algorithm for ad hoc networks
    WANG Qing wen Shi Hao shana Qi Qian
    2011, 34(10):109-114. DOI: 10.11835/j.issn.1000-582X.2011.10.017
    [Abstract](1531) [HTML](0) [PDF 6.85 M](1026)
    Abstract:
    To increase the multicasting efficiency of Ad hoc networks, a fuzzy logic multicasting algorithm (FLMA) is proposed. FLMA adopts the fuzzy logic to tolerate the imprecise information caused by dynamic network topology. The two input variables of the fuzzy logic system are the relative degree of the additional coverage node number and the relative degree of the residual energy. The deferring time of rebroadcast is the output variable of the fuzzy logic system, which is used to optimize the priority of the nodes to rebroadcast. FLMA reduces the redundant retransmission and the chance of the contention and collision, while balances the energy consumption of the nodes. Simulation results reveal that the FLMA achieves better performance than BCAST in terms of the network lifetime, average end-to-end delay, the average number of drops per node and the throughput.
    18  Design of an “all pass” compressive sensing random filter
    LIU Yu lin ZHANG Xian yu WANG Rui hua WU Li yun
    2011, 34(10):115-118. DOI: 10.11835/j.issn.1000-582X.2011.10.018
    [Abstract](1409) [HTML](0) [PDF 4.04 M](1203)
    Abstract:
    In Compressive sensing (CS), the random matrix is usually used as the measurement matrix, which is hard to design and difficult for computing. The random circulant matrix generated by random filter is suitable for signal measurement. A novel random filter is designed which is all pass in frequency domain, all real in both of time domain and frequency domain. The coherence property between the measurement basis and the signal basis is analyzed. The measurement vector can include all information of the original signal and it is convenient for computing. Numerical simulation results demonstrate that the filter is appropriate for signal collection and recovery.
    19  Feature extraction and recognition technique for human pulse signals
    CAI Kun bao CAO Ding DUAN Yun zi LUO De cheng LIU Zong xing
    2011, 34(10):119-123. DOI: 10.11835/j.issn.1000-582X.2011.10.019
    [Abstract](1759) [HTML](0) [PDF 5.09 M](1219)
    Abstract:
    In Chinese traditional medicine, the pulse signal plays an important role for diagnosis. To investigate the effective technique for identifying heroin druggers through the pulse signal, the feature extraction algorithm based on the biocepstrum and the third-order cepstrum entropy of the pulse signal is studied. On the basis of concise and rigorous discussion for the algorithm, the biocepstrum-based diagonal slice components are estimated for human pulse signals of 20 heroin druggers and 20 healthy normal subjects. The magnitude of the sample value of diagonal slice at m=n=1 and the third-order cepstrum entropy of magnitudes of sample values of the diagonal slice within a particular region are used as two feature parameters for every human pulse signal to form a feature vector. A classifier based on the criterion of squared Mahalanobis distance is successfully designed. Applying the designed classifier to 40 feature vectors, the correct identification rate reaches 87.5%. The research result shows that the method of the feature extraction and classifier design presented in is valuable for identifying the human pulse signals of heroin druggers.
    20  Low complexity antenna selection algorithmsfor base-station coordination system
    HAN Dong sheng YANG Wei
    2011, 34(10):124-129. DOI: 10.11835/j.issn.1000-582X.2011.10.020
    [Abstract](1707) [HTML](0) [PDF 7.25 M](1211)
    Abstract:
    Two kinds of antenna selection algorithm one proposed according to the characteristics of base-station coordination system. One is called aggregate channel frobenius norm antenna selection (ACFAS), another one is individual channel frobenius norm antenna selection (ICFAS). The object function of antenna selection in ACFAS is based on the aggregate channel frobenius norm of all of the coordinating base-stations and users, while the object function of ICFAS is based on the individual channel frobenius norm of every base-station and user. With the complexity analysis and system simulations, it is proved that the antenna selection algorithms proposed are capable of reducing the complexity, yet at a cost of system capacity lost. So they are suboptimal algorithms.
    21  Research on the improvement of the convergencespeed for CDMA system power control
    TAN Xiao heng WEI Wei HUANG Zhen lin
    2011, 34(10):130-135. DOI: 10.11835/j.issn.1000-582X.2011.10.021
    [Abstract](1330) [HTML](0) [PDF 6.40 M](1198)
    Abstract:
    Optimal power control with game-theory has been a hot research topic in code division multiple access (CDMA) system. However, the convergence speed of the power control algorithm based on traditional static game-theory is not fast enough and the power fluctuation is large during the iterative process. In order to solve this problem, dynamic game-theory is introduced into CDMA system power control algorithm. The simulation results show that the proposed algorithm, compared with the distributed power control algorithm based on the traditional static game theory, can improve the convergence speed obviously with the same power spending.
    22  Theoretic analysis and verification of the closed-loopself-oscillation for an MEMS gyroscope
    LIU Heng LIU Xian xue ZHANG Feng tian SU Wei ZHANG Fu tang
    2011, 34(10):136-141. DOI: 10.11835/j.issn.1000-582X.2011.10.022
    [Abstract](2077) [HTML](0) [PDF 7.64 M](1199)
    Abstract:
    By analyzing the requirement of the closed-loop control for the vibratory gyroscope, the behaviour of the self-oscillation system with automatic gain control was analyzed with averaging method to achieve system stability and stable equilibrium. The theoretic analysis and experiment show that the reference voltage must be larger than a critical value; the larger the reference voltage is, the larger the signal-noise-ratio is; the system phase error will cause the resonance frequency drift and decrease the vibrating amplitude; different constants of the low pass filters result in different time to achieve the stable states. The experiment shows the frequency accuracy of the close-loop self oscillation system is about ±8ppm in 10 minutes and vibration amplitude is about 0.1% error in an hour.
    23  An application based on container programming and genetic algorithm
    REN Wei ZHANG Xiao dong QIU Yu hui
    2011, 34(10):142-146. DOI: 10.11835/j.issn.1000-582X.2011.10.023
    [Abstract](1627) [HTML](0) [PDF 5.97 M](1108)
    Abstract:
    With the rapid growth of curriculums in colleges and universities and the number of students,automatic course arrangement method based on calculation algorithm has become an important issue of algorithm design and research. Based on Genetic Algorithm, a new binary encoding mechanism and classroom position filling method is put forward, which is applied to improve the load and efficiency of course scheduling system. In accordance with the ratio of weights in Fitness Function, this method abandons the way of random search, directionally and randomly generates chromosomes, simplifies the quantity of chromosome information, greatly shortens the running time of the system. In the aspect of management mechanism, user intervention is introduced,dealing with initial population with high proficiency and eliminating conflicts. Data from simulation experiment proves the astringency and high efficiency of this method. Moreover, the whole design of the system applies programming technology based on container, realizing the convenient processing of uncertain data.
    24  Frequency tracking method and simulation for coriolismass flowmter based on a new adaptive notch filter
    TU Ya qing SU Fen hua SHEN Ting ao ZHANG Hai tao
    2011, 34(10):147-152. DOI: 10.11835/j.issn.1000-582X.2011.10.024
    [Abstract](2025) [HTML](0) [PDF 6.34 M](1018)
    Abstract:
    In order to improve the long-playing frequency tracking ability in the signal processing for coriolis mass flowmeter (CMF) , a new IIR adaptive notch filter (ANF) is developed via steiglitz-mcBride method (SMM) and applied to filter the sensor output signal whose frequency, amplitude and phase are time-varying following the random walk model. The proposed method can detect the signal frequency fleetly and track the frequency variations continuously. The tracking performances of the proposed method and the adaptive lattice notch filter (LANF) method are investigated with computer simulations. Simulations demonstrate the superiority of the proposed method and show it has advantages of fast convergence rate, insensitivity to initial phase variations, and higher long-playing tracking stability and accuracy than LANF method.

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