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Table of Content

      
    16 June 2009
    Volume 39 Issue 3
    Articles
    Learning in bioinformatics
    GUO Mao-Zu, ZOU Quan, LI Wen-Bin, HAN Ying-Peng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  1-6. 
    Abstract ( 453 )   PDF (316KB) ( 2010 )   Save
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    Bioinformatics is a cross-disciplinary field that involves various fields of information science and biological science, which emerges from the human genome project. With the development of human genome project, we enter into the post-genome era from the computational  biology era. Systems biology is one of the most important fields in the post-genome era. This paper reviews the application of machine learning in computational biology and systems biology. Most important, it comes from an information researcher's  view.

    Parameters selection of a support vector machine using an improved estimation of the distribution algorithm
    WANG Xue-Song, CHENG Yu-Hu, HAO Ming-Lin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  7-10. 
    Abstract ( 324 )   PDF (703KB) ( 2174 )   Save
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    The learning performance and the generalization property of support vector machines (SVMs) are greatly  influenced by the suitable setting of some parameters. The parameters selection can be transformed into an optimization problem by defining the root mean square error of a SVM prediction model as an evaluation function. A kind of improved estimation of the distribution algorithm (EDA) with a chaotic-mutation operation was proposed and used to optimize parameters of a ε-SVM including a penalty factor, an insensitive loss coefficient and a width of a Gaussian kernel function. The improved EDA could take advantage of the randomness and ergodicity of chaos, which  could  solve the local minima problem of traditional EDAs. Simulation result of the prediction of a Chebyshev chaotic time series showed that the improved EDA was an effective method of solving the problem for parameters selection of a SVM.

    Detect outliers in time series data with multi-granule periodic patterns
    LUO Yu-Pan, SHANG Lin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  11-15. 
    Abstract ( 309 )   PDF (262KB) ( 2027 )   Save
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    Contributions on outlier detection in time series data have seldom taken into account the data cyclical nature and numerical attributes values. An algorithm to find periodic patterns under different granul arities was proposed, which could be  used to detect outliers in time series data with numerical attributes. This method could avoid a false alarm, and experimental results showed that it could not only correctly identify multi-ranule periodic patterns but also effectively detect outliers in data. Compared to outlier detection methods without periodic patterns, the results showed  that it could  reduce falsealarms.

    Research of protein-protein interaction extraction based on semi-supervised learning
    CUI Bao-Jin, LIN Hong-Fei, ZHANG Xiao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  16-21. 
    Abstract ( 459 )   PDF (914KB) ( 2668 )   Save
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    Semi-supervised learning methods including self-training and co-training were shown in the task of PPI on how to alleviate the tag burden as much as possible. On self training a word feature based SVM model was applied; In co-training word feature and dependency tree based SVM models were used. Experiments on four copra showed that the two methods were effective in reducing the amount of labeling PPI(protein-protein interaction). Comparing self -training to-cotraining can be more effective by using two separated views.

    Recent results on H∞ control of time-delay systems using  frequency-domain approaches
    ZHONG Qing-Chang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  22-30. 
    Abstract ( 342 )   PDF (424KB) ( 863 )   Save
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    Systems with delays frequently appear in engineering. Typical examples of time-delay systems are communication networks, chemical processes, and tele-operation systems. The presence of delays makes system analysis and control design much more complicated. In this survey paper, some of the recent results obtainedby the author on  H∞ control of time-delay systems were summarized. Theproblems discussed include the standard H∞ control problem, the delay-type Nehari problem, controller parametrisation and controller implementation. Some problems for future research were highlighted.

    Power system inter-area oscillation damping control with FACTS devies
    CAO Gang, DONG Chao-Yang, HUANG Ji-Bao, XUE Yu-Qing
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  31-36. 
    Abstract ( 369 )   PDF (620KB) ( 1212 )   Save
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    Various control schemes have been developed to solve the power system inter-area oscillation problem. Increasingly Flexible AC Transmission Systems (FACTS) devices are being planned to solve various power system operational and planning problems in some large-scale power systems in many countries. One of the design objectives is to reduce some critical inter-area oscillations existing inthe system. In this paper, FACTS controllers, based on variable structure control technology, were proposed to alleviate the interarea oscillation problem. Bothseries and parallel connected FACTS devices were studied. Case studies were presented to illustrate the effectiveness of the proposed controllers.

    Finite-time stabilization for a class of first-order nonlinear systems with unknown control direction
    Liu Yun-Gang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  37-46. 
    Abstract ( 307 )   PDF (287KB) ( 759 )   Save
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    In this paper, the finite time stabilization via state-feedback and adaptive technique was investigated for a class of first-order nonlinear systems with unknown control direction. Using the Nussbaum gain method, an adaptive state-feedback controller is successfully constructed, which guarantees the global stability of the closed-loop system, and the global finite time stability of the original system state (This was rigorously proven with the help of the celebrated L'Hospital’s Rule). A simulation example was provided to illustrate the effectiveness of the proposed approach.

    New development of energy-based control based on generalized controlled Hamiltonian systems
    LIU Yu-chang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  47-55. 
    Abstract ( 408 )   PDF (335KB) ( 1948 )   Save
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    The generalized controlled Hamiltonian systems developed from traditional Hamiltonian systems, describe a kind of open dynamical systems, which may have energy dissipation and exchanges with their environment. The developing course of Hamiltoian systems was  first introduced, and then both of the research hot topics and newest development on general Hamiltonian  systems were given. The aim of this paper was to give the reader a whole picture of both energy-based control and  development of research of generalized Hamiltonian systems.

    H2 white noise estimation for linear continuous-time systems with delayed measurements
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  56-61. 
    Abstract ( 342 )   PDF (845KB) ( 1598 )   Save
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    he H2 optimal input white noise estimator for linear continuous-time stochastic systems with delayed measurements was studied. The proposed approach was based on the re-organization innovation methods and projection theory in Hilbert space. The key technique of the proposed algorithm was converting the delayed measurements to non-delayed measurements. Then, The optimal white noise estimators were given by computing the solution of two standard Riccati equations with the same order as that of the original system. The proposed method is sample and does not need to compute both complex partial differential equation and operator equation of Riccati.

    Synthesis of (La0.8Sr0.2)0.9MnO3-δ powder by a gel-casting technique as cathodes for solid oxide fuel cells
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  62-66. 
    Abstract ( 289 )   PDF (1150KB) ( 1084 )   Save
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     (La0.8Sr0.2)0.9MnO3-δ (LSM) powders were successfully synthesized via a gel-casting technique and traditional solid state reaction method by using oxide and carbon as raw materials. The perovskite phase formation temperature of LSM powders synthesized by the gel-casting technique was about 850℃, which is nearly 150℃ lower than that of LSM powders synthesized by the conventional solid-state reaction route. The significantly reduced phase formation temperature of the gel-casting LSM powder was most likely due to the homogeneously distributed and immobilized precursor particles in a polymeric network, which promoted the sintering and crystallization process. Furthermore, the electrochemical catalytic performance of LSM electrodes prepared by LSM powders synthesized gel-casting technique and sintered at different temperature was also investigated in detail.

    The magnetic glass state in the magnetocaloric material Gd5Ge4
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  67-70. 
    Abstract ( 391 )   PDF (775KB) ( 1246 )   Save
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    The metastable property of glasslike dynamics at low temperature of Gd5Ge4 was presented in contrast to the stable frozen spin glass state in cobaltite La0.88Sr0.12CoO3(LSCO). Through investigating the effect of temperature cycle on magnetization at the low temperature region after the zero field cooled procedure ofGd5Ge4andLa0.88Sr0.12CoO3respectively, it was found that the magnetization continues to increase with increasing the temperature cycle in Gd5Ge4, while there was hardly any effect on magnetization inLa0.88Sr0.12CoO3. The dc magnetization and ac susceptibility were also measured on Gd5Ge4 and La0.88Sr0.12CoO3. The peaks of ac susceptibility in Gd5Ge4 did not move to the higher temperature region with increasing frequency, which were different from the phenomena of La0.88Sr0.12CoO3. This kind of magnetic glass state in Gd5Ge4 is quite different from conventional spin glass.

    Synthesis and evaluation of ternary copolymerization cationic polyacrylamide
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  71-76. 
    Abstract ( 353 )   PDF (543KB) ( 1792 )   Save
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    A new polymer materials——cationic flocculant P(AM-DAC-DMDAAC) was synthesized by aqueous solution polymerization using acrylamide (AM) as the molecular backbone, acryloyloxyethyl trimethyl ammonium chloride (DAC) and dimethyl diallyl ammonium chloride (DMDAAC) as the cation group. The obtained optimum reaction conditions were as follows: mass fraction of monomer 30%, initiator temperature 12?℃,pH 5.0, cationic monomer concentration 25%, initiator AM-01 0.03% and K2S2O80.003%. The molecular weights of polymers were measured by the viscosity method, and the structure of the polymers were characterized by the infrared absorption spectrum and nuclear magnetic resonance. The polymers’capability of flocculating performance was investigated in waste water.

    Influence of zinc oxide in a phosphating bath on phosphate coating on AZ61 magnesium alloy
    GAO Yu, DU Ai-ling, YANG Yan-ling
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  77-80. 
    Abstract ( 381 )   PDF (845KB) ( 1761 )   Save
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    The influences of the mass concentration of zinc oxide(the main film-forming substance) in the phosphating bath on the microstructure and properties of the phosphate coating on AZ61 magnesium alloy were studied. The structure, surface morphologies and compositions of the phosphate coatings were observed and analyzed by using a metallographical microscope,SEM and EDS. Anodic polarization measurement was used to assess the corrosion resistance of the phosphate coating on the magnesium alloy. The results indicated that the phosphate coating obtained from a phosphating bath with a lower concentration of ZnO was a loose and defected structure, without exhibiting enough corrosion resistance. The phosphate coating obtained from a phosphating bath with a higher mass concentration of ZnO is composed of coarse crystals and the thickness of the coating was  uneven,  showing poor corrosion resistance. The uniform and intact phosphate coating which was obtained from a phosphating bath with a medium mass concentration of 2.0g/L ZnO showed high corrosion resistance in a 3.5% NaCl solution.

    Study of key technologies of titanium monolithic components machining
    SUN Ji, LI Jian-feng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  81-88. 
    Abstract ( 421 )   PDF (1398KB) ( 2622 )   Save
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    Aimed at the difficult-to-machine property of titanium alloys, as well as large dimension, complicated construction and large distortion of titanium monolithic component used in large commercial airplanes, research actuality, existing problems and development trends of titanium alloys machining were analyzed. Requirements and the developing trends of titanium tooling techniques such as tool materials, tool structure, and micro edge treating et al were elaborated. Titanium fabrication technologies were discussed which should be reinforced and include type and path of cutting, parameters optimization based on cutting stability, and distortion control and correcting, et al. The relationship between milling parameters and surface integrity was also analyzed. The purpose of this work was to provide a guideline for theoretical research and engineering application.

    The technology of lattice graphics LCD display based on the best geometrical way beeline interpolation
    FENG Xian-ying, ZHANG Cheng-liang, WEI Hua-chuan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  89-93. 
    Abstract ( 343 )   PDF (398KB) ( 1874 )   Save
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    The principle of the best geometrical way beeline interpolation was given, and the method to lattice graphics LCD display was introduced. The requirement for data conversion and program diagram was given, which can be realized with C51 advanced language. This method can be applied as a base function module in the MCU system of a real time display curve graph. In addition, this way has proved its practicability for the low deviation——half step and high real time performance.

    Fast integration algorithms for dynamics of a flexible space robots system
    TIAN Fu-yang, WU Hong-tao, ZHAO Da-xu, SHAO Bing, MIAO Qun-hua, ZHU Jian-ying
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  94-98. 
    Abstract ( 311 )   PDF (399KB) ( 1633 )   Save
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    The dynamics model of flexible space robots was proposed, and the fast integration method to solve the complex differential-algebra equation was discussed. First, a dynamics model was set up based on the Lagrange method. Second, the differential-algebra equation of dynamics of the space flexible robots was gained according to the type of the joint (active or passive). Finally, the fast integration method to solve the complex differential-algebra equation was used. Simulations results showed that the dynamic modeling and fast integration techniques of the flexible space robot proposed was very useful.

    C 1 natural element method for strain gradient elasticity
    NIE Zhi-feng, ZHOU Shen-jie, WANG Kai, KONG Sheng-li
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  99-102. 
    Abstract ( 384 )   PDF (609KB) ( 2091 )   Save
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    C 1 interpolant can be constructed by embedding Sibson interpolant in the Bernstein-Bésurface representation of a cubic simplex. The essential boundary conditions were directly imposed in a Galerkin scheme for strain gradient elasticity because C 1 interpolant has the interpolation for nodal functions and nodal gradient values. Boundary layer analysis and infinite plate with circular hole under biaxial tension were analyzed to illustrate the effectiveness of the method.

    Multi-objective optimization for the geometrical parameters of the low-specific-speed centrifugal impeller
    QU Yan-peng, CHEN Song-ying, YANG Xin-zhen, XIE Fu-chao, LI Wen-feng, SONG Xiu-qin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  103-105. 
    Abstract ( 304 )   PDF (249KB) ( 1469 )   Save
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    The efficiency of a lowspecificspeed centrifugal pump is concerned with the loss, the NPSHr and the stability of the head curve. The multiobjective optimization function of the geometry parameter of impeller in a lowspecificspeed centrifugal pump was found by the linear weighted combinations method with the arm of the least of the energy loss and the NPSHr and the elimination of the hump. The optimizations of the example proved that the designers can fuzzy evaluate the importance of the target functions with this method by fact experience and confirm the weight of the targets. The efficiency, NPSHr and stability of the pump can be optimized to get further scientific project in design.

    Study on risk evaluation and water inrush disaster preventingtechnology during construction of karst tunnels
    ZHANG Qin-song, LI Shu-cai, HAN Hong-wei, GE Yan-hui, LIU Ren-tai, ZHANG Xiao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  106-110. 
    Abstract ( 359 )   PDF (793KB) ( 2309 )   Save
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    During tunnel construction in the mountains of southwest China, karst and unfavorable geological conditions often occur. Tunnel construction often encounters unforeseen disasters, such as water inrush, bursting mud, and collapse which cause great hidden troubles to safety. Taking the Wuchiba Tunnel as an example, through applying the supplement geology survey and geology analysis, the karst development was discussed. In the risk evaluation of dangerous parts along the tunnel, the factors such as formation lithology, geological structure, underground water level, and the forecasted discharge were synthetically considered. The risk evaluation system with 4 ranks about karst tunnels was put forth. Based on the risk rank, the advanced forecasting program was designed for the different parts with different ranks, and the disaster prevention measures can be made with the predictable results. The study has great significance for disaster prevention of karst tunnels.

    Research on the wellbore stability model coupled mechanics and chemistry
    ZHANG Le-wen,QIU Dao-hong,CHENG Yuan-fang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  111-114. 
    Abstract ( 357 )   PDF (554KB) ( 1787 )   Save
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    Based on the poroelasticity theory and seepage mechanics, the  wellbore stability model coupled mechanicschemical effect for shale formation was put forth. Rules about activity of drilling fluids and membrane efficiency affecting on wellbore collapse pressure were obtained by the model, which could offer the theoretical basis for research on wellbore stability.

    Study of the prediction of karstfractured groundwater in prediction and early warning system of tunnel geologic hazards
    LIU Bin, LI Shu-cai, ZHANG Qing-song, LI Shu-chen, XUE Yi-guo
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  115-121. 
    Abstract ( 332 )   PDF (1447KB) ( 1202 )   Save
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    In the prediction of karst-fractured groundwater, thorough and systemic research is deficient, and there are problems that the accuracy and precision is low. Research on the new technique can not catch up with the  engineering demand. For solving this problem, the advantages of the common methods were integrated, and a new integrative method feasible to karst-fractured groundwater prediction was established. First, the advanced geological forecasting methods used in tunnel construction were summarized. Then, based on the scientific process, the integrative advanced geological forecasting method for karst-fractured groundwater was established by comprehensive analysis on the advantages of all the prediction techniques. Finally, the water gush disaster was successfully forecast and earlywarning in the project example. With high systematicness and efficiency, the use of this integrative geological forecasting method makes the accuracy and precision of the prediction highly improved and gushing water disaster risk rationally evaluated, which is worthy to be generalized.

    Study on early warning and disaster prevention system of water inrush into high risk karst tunnels
    GE Yan-hui, LI Shu-cai, ZHANG Qing-song
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  122-128. 
    Abstract ( 351 )   PDF (1058KB) ( 1461 )   Save
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    According to the current situation of the early warning system in our country and the characteristic of water inrush in karst tunnels, the early warning disaster prevention system was discussed in the aspects of early warning mechanism,which consisted of early warning organization systems, operation mechanism and warning insurances, and emergency response planning and drilling. The four-color warning mechanism was proposed for the first time in our country and the emergency response planning and drilling were consequently improved. It has been successfully applied in the Wuchiba and Qiyueshan Tunnels of Hurongxi Highway and it can be used in preventing water inrush disaster in high-risk tunnels in karst zones in the future.

    The strain measurement techniques based on the static resistive strain gauge and optical fiber strain sensor and their applications in geo-mechanical model tests
    LI Yong, YANG Qiang, ZHU Wei-shen, LI Shu-cai, ZHANG Qiang-yong, WANG Han-peng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  129-134. 
    Abstract ( 322 )   PDF (1022KB) ( 2075 )   Save
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    Combined with the technologies used in the 3D geomechanical model test of the Baziling branchingout tunnel, how to apply the two strain measurement technologies to the geomechanical model tests and how to get the values and angles of the principle stress of the measuring points through the received monitoring data of strain were given. Then, the tests measuring results were compared with the numerical simulation results, which were found to be in good agreement. The tests results proved that better experimental data could only be obtained by the combination of resistive strain measuring and optical fiber strain measuring.

    Investigation on triaxial creep claystone under pore pressure
    WANG Jun-guang, LIANG Bing
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  135-138. 
    Abstract ( 302 )   PDF (1096KB) ( 1419 )   Save
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    Triaxial creep experiments of a kind of claystone under pore pressure were performed with a triaxial creep testing device which has the system of pore pressure. The effects of axial stress σ1 and confining pressure σ3 on the creep, and the pore pressure p were investigated. By creep experiments with different stress states and analyzing the results of different pore pressures, it was found that for constant axial stress and constant confining pressure, with the increase of pore pressure, the deformation amount of creep was reduced, the steadystate creep strain rate was decreased, and the threestate of creep time became longer. The creep behavior of claystone was analyzed with a classic creep model.

    Application of fuzzy cluster analysis to regional water resources carrying capacity evaluation
    WANG Hao-fang,WU Mei,CHEN Wen-yan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  139-143. 
    Abstract ( 338 )   PDF (248KB) ( 1369 )   Save
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    he fuzzy cluster analysis principle and calculation approaches were introduced and adopted to evaluate the water resource carrying capacity of seventeen regions in Shandong Province. The evaluation results showed that Zibo City, Weihai City, Qingdao City, Weifang City, Jining City, Rizhao City, Zaozhuang City, Laiwu City, Yantai City, and Linyi City were in the higher capacity of water resources, while the water resources carrying capacity  of the other 7 cites were low.

    The establishment of a 3D digital model of a bat'svocal organs using micro-CT
    WANG Fu-xun, ZHAO Yi-jun, CHEN Gang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  144-146. 
    Abstract ( 397 )   PDF (692KB) ( 1709 )   Save
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    It is useful for referencing the characteristics of a bat's echolocation on improving the performance of intelligent devices, and a precise biological model is the  prerequisite for such studies. The principle of image reconstruction was introduced. The images were scanned by a micro-CT. A 3D digital nose model of the Chinese woolly horseshoe bat, with its vocal organs emitting ultrasonic pause for echolocation, was made using a computer. This digital model has highprecision and could be changed on a  matrix scale according to the needs of the study. This method and the digital nose model of a Chinese woolly horseshoe bat have not been previously mentioned.

    The establishment of a 3D digital model of a bat'svocal organs using micro-CT
    WANG Dao-yi, CHEN Bao-fu, LIU Yuan-an
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  147-150. 
    Abstract ( 367 )   PDF (687KB) ( 1483 )   Save
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    Based on the analysis of the statistical data of the media access times in a multiservices operator’s (MSO) media-on-demand network in one day, a random media access model was generated. Based on this media access model, an IPTV system was built, and several key issues, such as the throughput of central server and the cache ratio of the regional servers, and on content delivery policies were studied. The simulation result showed that the increasing throughput capability of the central server and the cache ratio of the regional servers can increase the QoS of the IPTV systems only when these parameters can not meet the requirement of content access regulation.

    Research of the hydraulic adjustment method for a district heating system
    ZHOU Shou-Jun, ZHAO Wei-En, CHEN Ming-Jiu, TIAN Mao-Cheng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  151-153. 
    Abstract ( 395 )   PDF (376KB) ( 1943 )   Save
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    To solve the hydraulic maladjustment problem of a district heating system, the fluid network analysis method was adopted to establish a mathematic model of a hydraulic operating mode for a district heating system. The solution algorithm of the mathematic model was given. In addition, simulation regulation software was developed by network developing language JAVA according to the simulation analysis method. This software was developed for a specific real case. Then a new method was provided to effectively solve hydraulic maladjusted problems of a district heating system.

    Circumferential inflow air distributing rules in a natural draft  wet-cooling tower under crosswind conditions
    GAO Ming, SHI Yue-Thao, WANG Ni-Ni, SUN Feng-Zhong, PING Ya-Ming
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2009, 39(3):  154-158. 
    Abstract ( 414 )   PDF (369KB) ( 1374 )   Save
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    The circumferential inflow air on the bottom of a natural draft wet-cooling tower were studied under windless and crosswind conditions. The entire research was conducted in a closed lab with a thermal state cooling tower model. The research showed that the circumferential inlet wind was wellproportioned and axisymmetric under windless conditions, that is, the heat and mass transfer performance through fillings zone was also axisymmetric. The axisymmetric distribution  of circumferential inlet wind velocity was destroyed under crosswind conditions.This phenomenon was very obvious when environmental crosswind velocity was more than 0.2m/s. When the environmental wind velocity was about 0.5m/s, the circumferential inlet wind velocity in windward sidewas about 1.875 times the windless conditions, while the circumferential inlet windvelocity in leeward side was about 0.3 times the windless conditions. Thus, the environmental crosswind affected the airflow rate entering into the cooling tower, and then deteriorated the heat and mass transfer performance.