Table of Content

31 October 2010, Volume 44 Issue 10 Previous Issue    Next Issue

Engineering Mechanics

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Flow Resistance Characteristics of R410A-oil Mixture during Evaporation in a Small Diameter Enhanced Tube HU Haitao1，HUANG Xiangchao1，DING Guoliang1，DENG Bin2，GAO Yifeng3 2010, 44 (10):  1317-1321.  Abstract ( 3458 )   Save An experimental study of flow resistance characteristics of R410Aoil mixture during evaporation inside a 5 mm internally spiral grooved enhanced tube was performed. The test results show that the frictional pressured drop of R410A initially increases with vapor quality and then decreases, presenting a local maximum in the vapor quality range between 0.7 and 0.8; the frictional pressure drop of R410Aoil mixture increases with increasing nominal oil concentration, vapor quality and mass flux; the presence of oil enhances frictional pressure drop maximum by 120% as the oil concentration increases from 0 to 5% at a vapor quality of 0.9. The frictional pressure drop of R410Aoil mixture in 5 mm enhanced tube is about 10% to 30% higher than that in 7 mm enhanced tube. The deviations of the prediction of existing correlation for 7 mm enhanced tube to the pressure drop characteristics of R410Aoil mixture in 5 mm enhanced tube are within ±40%. Based on the experimental data of R410Aoil mixture in 7 mm and 5 mm enhanced tubes, a new correlation of frictional pressure drop was developed by considering the mixture properties, which agreed with 95% of the experimental data within the deviation of ±20%. Related Articles | Metrics

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On Compatibility of Engine Seal Parts with Dimethyl Ether YANG Meimin,ZHANG Wugao,PU Gengqiang,HUANG Zhen 2010, 44 (10):  1322-1326.  Abstract ( 3578 )   Save Dimethyl ether as fuel for compression ignition engines causes compatibility problem between seal parts and fuel in engine fuel system. The compatibility of seal materials with DME was deeply investigated. Many kinds of rubber materials were chosen to test the expansion, the tensile strength, the tear strength and the hardness. The experimental results show that EPDM has a good resistance to DME; the purity of DME, various lubricant additives and concentrations in DME, different constitutions of EPDM rubber have a certain impact on the resistance of EPDM to DME; and the chosen EPDM has an acceptable volume swelling rate and mechanical performance in a short time when using diesel to adjust highpressure oil pump for fuel DME uniformity in every cylinder. Related Articles | Metrics

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An Experimental Study on the Combustion and Emissions Characteristics of Stratified Charge Compression Ignition Using Portinjection nheptane and Directinjection isooctane ZHOU Xiaoxin,LU Xingcai,JI Libin,HUANG Zhen 2010, 44 (10):  1327-1331.  Abstract ( 3266 )   Save An experimental study was conducted on the combustion and emissions characteristics of dualfuel SCCI on a singlecylinder engine, applying the portinjection nheptane and incylinder direct injection isooctane. Twostage combustion of homogenous charge of nheptane and air before top dead center ignites the isooctane, so the SCCI could achieve a staged combustion. The effects of the load and premixedratio were explored. The test result shows that SCCI offers good potential to expand the operating range, because the value of IMEP is up to 0.73 MPa when the maximum pressure rise rate is 0.87 MPa/(°). Operating points with high NOx emissions have the most nheptane amount of portinjection. Meanwhile, when the nheptane amount of portinjection is fixed, increasing the isooctane amount of direct injection can lower the CO and THC emissions. Related Articles | Metrics

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Flow Drag and Heat Transfer Performances of Dragreducing Fluid with Carbon Nanotubes Added SONG Bin,LIAO Liang,LIU Zhenhua 2010, 44 (10):  1332-1336.  Abstract ( 3434 )   Save A new kind of dragreducing liquid was developed, which has not only the dragreducing characteristics, but also the enhanced heat transfer characteristics, because of adding carbon nanotubes (CNT) into the base fluid. In this study, the base fluid was pure water; the dragreducing additive CTAC (cetyltrimethyl ammonium chloride) and multi wall CNT were added to the base fluid to make dragreducing fluids. The production process was developed, the appropriate composition fraction was found, and the thermal and rheological properties were measured. The test indicates that the fluid temperature has a strong influence on the dragreducing and heat transfer characteristics. The dragreducing characteristics does not change after the addition of CNT， but the heat transfer characteristics have been greatly enhanced. The enhanced heat transfer technology of nanofluid can be used to solve the heat transfer deterioration problem of pure dragreducing fluid. Related Articles | Metrics

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The Modified Integrated Cylindrical Source Model YU Xin1,LIAN Zhiwei1,CHEN Jianping2，PAN Li1,WANG Yuemei1 2010, 44 (10):  1337-1341.  Abstract ( 3166 )   Save A thermal resistance correction factor aimed at the backfill material of the borehole was developed by analyzing the unsteady heat transfer of vertical embedded pipe for ground source heat pump, and the heat shortcircuit modification was introduced to modify the mean temperature of the circulating water. Meanwhile, a cylindrical source integrated modified model was developed based on the modification of the existing Carslaw cylindrical source model. The accuracy of the modified model was proved by the comparison of the calculation result and the experimental one, and the influence of the backfill grout, the equivalent radius, thermal ununiformity and the heat shortcircuit on the result was also further analysed. Related Articles | Metrics

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Performance Prediction of Transonic Axial Compressor at Offdesign Points HU Jiangfeng，OU YANGHua，ZHU Xiaocheng，DU Zhaohui 2010, 44 (10):  1342-1346.  Abstract ( 3447 )   Save The improved loss and deviation models for transonic compressor were developed based on 2D streamline curvature method according to public research findings. Considering 3D and Reynolds effects, the internal flow field of transonic compressor rotorNASA rotor 37 was calculated, thus obtaining the characteristic curve of design and offdesign points. The comparison of simulation and experiment value shows that this method can predict the performance and distribution of parameter with higher accuracy for axial compressor, and can be used for optimization and design of compressor. Related Articles | Metrics

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Experimental Study on Dimethylether SCR NOx Reduction YAN Ying,ZHANG Wugao,CHEN Xiaoling,LIU Jia 2010, 44 (10):  1347-1351.  Abstract ( 3230 )   Save Selective catalytic reduction (SCR) activity for NOx conversion to N2 over 7% MoO3/γAl2O3 (mass fraction) was investigated with Dimethylether (DME) as a reductant. The effects of the reaction temperature, DME/NO ratio as well as the oxygen inlet concentration were studied respectively. The carboncontaining product distributions were presented. NOx conversion with NO and NO2 respectively as NOx source was also investigated. The results show that between the range of 250℃ to 500℃, under atmospheric pressure, when operation temperature increases, NOx conversion increases at the beginning and then decreases. DME/NO ratio has a little impact on NO conversion. When the oxygen inlet concentration increases, NOx conversion increases at the beginning and then decreases, and the highest conversion rate of NO is about 53% when the oxygen inlet concentration is 5%. NO2 is easier for selective reduction than NO with DME as the reductant. The main carboncontaining products are CO and CO2, while a little CH3OH and H2CO have also been detected during the experiment. Related Articles | Metrics

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Hybrid Engine Cold Start Emissions WANG Cunlei,YIN Chengliang,YU Haisheng 2010, 44 (10):  1352-1355.  Abstract ( 3482 )   Save The key parameters influencing cold start HC and NOx emissions, including motoring speed, “fuelon” speed and ignition retard, were analyzed by studying engine start ignition, fuel delivery and air charging strategies. The results show that higher motoring speed helps to reduce start fuel, improves fuel atomization and completes combustion, and thus reducing the HC emission. But too high a motoring speed will deteriorate NOx emission. Ignition retard can accelerate TWC lightoff effectively, but too much of it will cause unstable combustion and misfire, and deteriorate HC and NOx emissions simultaneously. By studying the law of start emission, the optimized parameters were selected, laying a foundation for further accurate emission calibration. Related Articles | Metrics

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Dynamic Torque Coordination Control Strategy of Integrated Starter Alternator Damper (ISAD) Hybrid WEI Changhe1,2，WANG Zhong1，LIANG Lei1，XU Guangju1 2010, 44 (10):  1356-1361.  Abstract ( 3900 )   Save Aimed at the characteristic of each parts of system of integrated starter alternator damper(ISAD), in this paper the dynamic torque coordination controlling strategy of ISAD hybrid with best matching of diesel, ISG, batteries, and transmission system was analyzed. Based on the requirement and map, the torque was set as the control parameter to confirm the principle and target of both diesel and ISG. On the Matlab/Simulink working plate, the implement of dynamic torque coordination controlling strategy under different work conditions was simulated and studied while a simulation test on condition of CYC_ECE_EUDC was conducted. The result shows that the strategy meets the requirements of speedy starting, compensating torque in low speed and constant charging power. Both diesel and ISG are working on the region of high efficiency, and SOC is contained at the best working area. The ISAD is carried into effect, providing a theoretical basis for further selfdevelopment of control software platform. Related Articles | Metrics

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Influence of Oil on Flow Condensation Frictional Pressure Drop of R410A inside Small Diameter Horizontal Smooth Tubes HUANG Xiangchao1,HU Haitao1,DING Guoliang1，ZHU Yu1,DENG Bin2,GAO Yifeng3 2010, 44 (10):  1362-1366.  Abstract ( 3535 )   Save Influence of oil on flow condensation frictional pressure drop of R410A inside 5 mm and 3 mm O.D. horizontal smooth tubes was investigated experimentally. The research results show that the presence of oil always decreases the flow condensation frictional pressure drop of R410A inside smooth tubes, and the decrement can reach up to 19% at the present test conditions; the decrement increases with the increase of nominal oil concentration, and decreases with the increase of mass flux and vapor quality. A new correlation of frictional pressure drop for R410Aoil mixture flow condensation inside small diameter smooth tubes was developed based on the mixture properties, which agrees with all the experimental data within the deviation of -20% ~ +30%. Related Articles | Metrics

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Knock Control Based on Discrete Wavelet Transform and FPGA WANG Yanyan,YANG Jianguo，SONG BaoYu,ZHANG Kun 2010, 44 (10):  1367-1371.  Abstract ( 3200 )   Save To increase the accuracy of knock detect and control of gasoline engine, discrete wavelet transform(DWT) and Field Programmable Gate Array(FPGA) were applied to knock control. Knock edge feature was extracted from vibration signal by using DWT. A parameter of relative energy for knock intensity evaluation, and a knock feedback ignition control strategy were proposed. The knock control model was established, verified by simulink test, and actualized on FPGA. The results show that the knock control method based on DWT and FPGA can diagnose knock accurately, is suitable for realtime control, and can make gasoline engine work at slight knock area, which is useful for improving the performance of gasoline engines. Related Articles | Metrics

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Effect of Refrigerant Charge on the Performance of a Direct Expansion Solar Assisted Heat Pump Water Heater KONG Xiangqiang，ZHANG Dong，LI Ying，LIN Lin，YANG Qianming 2010, 44 (10):  1372-1377.  Abstract ( 3324 )   Save Simulation program of a direct expansion solar assisted heat pump water heater system was coded based on the distributed parameter and homogeneous flow mathematical models of solar collector/evaporator and condenser, the lumped parameter models of compressor and thermostatic expansion valve and the refrigerant charge model. The calculation and the experiment results were compared. Based on the calculation results, the operational parameters and the performances of the system were obtained. The effects of changing the refrigerant charge on heating time, the superheat of collector outlet, evaporating pressure, condensing pressure, power of the compressor, collector efficiency and coefficient of performance (COP) were analyzed. Some references to judge optimum refrigerant charge were proposed. Related Articles | Metrics

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Experimental Research on the Ternary Solution Absorption Refrigerator with the Solution Heat Exchanger CHENG Yulong,WU Yuyuan,WU Tiehui,LIU Kewei 2010, 44 (10):  1378-1381.  Abstract ( 3545 )   Save It was shown by previous researches that the system of ammoniawaterlithium bromide absorption refrigerator, without solution heat exchanger and solution pump had a better thermal performance, a lower initial investment and a higher safety, compared with the previous patterns. For further improvement of the system, three novel systems with solution heat exchanger were proposed and designed. The experiments were also performed for these novel systems. When wNH3=50%, wLiBr=15%, the coefficient of the performance (COP) of systemⅠwas improved by 27.8%, and that of systemⅡwas improved by 65%, compared with the system without solution heat exchanger. By means of the solution heat exchanger, the COP was increased greatly. Finally, the defects of systemⅡwere discussed and further improved systemⅢ was presented. Related Articles | Metrics

Communication and Transportation

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Mechanical Properties of Hotdip Galvanized Dual Phase Steel DP590 and Its Constitutive Model NIU Jianhuia，ZHU Pinga，b，GUO Yongjina 2010, 44 (10):  1382-1387.  Abstract ( 4502 )   Save Quasistatic mechanical property and flow behavior in large strain of hotdip galvanized dual phase steels, DP590, were investigated by uniaxial tensile and bulge tests respectively. Dynamic mechanical properties of DP590 at medium to high strain rates were also tested by highspeed electrohydraulic servo test machine and SHTB device. It is shown that DP590 possesses weak anisotropy and its dynamic effective stressstrain curves tend to be convergent as the strain increases. Therefore, a convergent viscoplastic constitutive with a mixed hardening rule based on anisotropy yielding criteria, YLD2003, was proposed. In addition, parameter identification for new constitutive was discussed. Finally, the proposed constitutive was adopted to simulate the crash behavior of a thinwalled structure subjected to axial loading condition. The simulation results showed high agreement with those of the experiment，which proved the proposed constitutive was more suitable for fine simulation analysis. Related Articles | Metrics

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Calculation of the Sinkage and Trim of Trimaran and Their Effect on Wave Making Resistance WANG Zhong1,LU Xiaoping1,FU Pan2 2010, 44 (10):  1388-1392.  Abstract ( 3655 )   Save The wave making resistance, the sinkage and trim of trimaran in calm water were iteratively calculated based on the Rankine source panel method. During the process, the NURBS surface was used to express the ship surface, the instantaneous mean wetted surface was calculated according to the preiteratively calculated sinkage and trim, and the fully quadrilateral mesh was generated by the paving method. The comparison between the calculated sinkage and trim and the experimental results indicates that with present method the trimaran sinkage and trim could be calculated very accurately, and the wave making resistance calculation precision could also be enhanced. Related Articles | Metrics

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Numerical Study on Cylinder Entering Water in Wave WANG Wenhua,WANG Yanying 2010, 44 (10):  1393-1399.  Abstract ( 3634 )   Save In order to study the influence of wave on water entry of cylinder, a CFD method was presented to numerically simulate the physical process of cylinder vertically entering water in regular wave. In this method, free surface capturing method and Cartesian cut cell mesh system were adopted to treat moving free surface and solid boundary. In combination with the theories of a pistontype wavemaking and sponge damping waveabsorbing, the CFD method was applied in the implementation of numerical wave making and absorbing. Furthermore, the effect of wave parameters (wave height, wave period, wave phase versus cylinder touching free surface, and so on) on the hydrodynamic was analyzed. Finally, the application case of lifting operation from a crane ship in wave was numerically simulated, and the tension variation of wire and motion characteristic of cylinder under different working conditions were mainly studied. Related Articles | Metrics

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Stability and Bifurcations Analysis of Submarine during Emergency Ascent DAI Yuliang1,YU Keyun2 2010, 44 (10):  1400-1404.  Abstract ( 4268 )   Save In this paper the motion stability and bifurcation theory of a nonlinear system and the principles of continuation based on homotopy techniques were applied to stable state response and motion stability analysis of submarines during emergency ascent. The stability analysis results were verified by simulations using direct numerical integrations of the fully nonlinear, coupled six degreesoffreedom equations of motion for the submarine. The control surface deflections, excess buoyancy and speed effects on the stability of the submarine during emergency ascent show that emergency rising motion is not always restricted to the vertical plane even under port/starboard symmetric conditions. Complicated outofplane motions may be generated, and the submarine may lose stability under some critical conditions. The singularity and bifurcation theory was used to explain the mechanism for these phenomena, providing a theoretical basis for maneuvering and controlling submarine during emergency ascent. Related Articles | Metrics

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Probability Distribution of Effective Impact Angle of Ship Bow Flare Impact CHEN Zhen,ZAHNG Shilian,XIAO Xi 2010, 44 (10):  1405-1408.  Abstract ( 3531 )   Save Based on the randomness of wave surface slope, the probability distribution of effective impact angle of bow fare impact was studied. The deadrise angle at the impact region of ship hull surface was expanded with Taylor series in the vertical normal plane, and the probability density function for the angle was derived on the basis of random characteristics of ship motion response. In terms of the theory of random ocean waves and Chuang’s analytical method of slamming pressures for vehicles, the probability density function for the effective impact angle was derived, providing basis for further study of the probability prediction method of bow flare impact. Related Articles | Metrics

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Influence of Ocean Waves on Ship Propulsion Shaft LU Jingming1,2,ZHOU Haigang2,DING Libing2,BAO Suning2,MA Jie1 2010, 44 (10):  1409-1413.  Abstract ( 3719 )   Save The 2D plane method is not accurate enough to analyze the effect on propulsion shaft system by hull deformation, therefore, the 3D FE model of a bulk carrier was conducted. The wave pressure was calculated and loaded automatically based on Patran command language (PCL). The deformations of ship construction in various sea waves were calculated and the effect on bearing load was analyzed. The result shows that the deflection of hull under shaft line is small in and under the sea state 4. The deflection of hull under shaft line is increased by sea state. And it is more than 4 mm in the sea state 8, affecting the shaft bearing load enormously. The deflection of hull under shaft line in vertical, horizontal and longitudinal directions is increased when the course heading is 30°. Related Articles | Metrics

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Optimization Design of Hull Lines Based on Rankine Source Method ZHANG Baoji1，MA Kun2 2010, 44 (10):  1414-1417.  Abstract ( 3770 )   Save In the preliminary design of a ship, in order to obtain a hull form with excellent resistance performance rapidly and accurately, the optimized design program of ship lines using optimal fullscale ship was developed, which combined the Rankine source method (one of the wavemaking resistance theory of potential flow ) and viscous theory with the optimization technique. In the optimization process, the SUMT interior point method of Nonlinear Programming (NLP) was proposed with reducing wavemaking resistance as the main objective function, with appropriate displacement as a basic constraint condition and the parameters of hull form modification function as design variables. Finally, the numerical optimization examples for different regions of forebody of fullscale surface vessel were provided, which indicated that the resistance was reduced distinctly by this optimal method. Related Articles | Metrics

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Theoretical Prediction Method of Energy Saving Effect of Prepropeller Energy Saving Devices SHEN Hailong，CAI Haopeng，SU Yumin 2010, 44 (10):  1418-1422.  Abstract ( 3790 )   Save At present, the prediction of energy saving effect of energy saving devices is still dependent on model test. There still exist some difficulties in theoretical prediction method. So a theoretical prediction method of energy saving effect for prepropeller energy saving devices was proposed in this paper based on surface panel method and RANS equations. First，the wake stream field of one full form ship was predicted, including the naked hull and hull with energy saving devices. Based on this, the unsteady hydrodynamic performance prediction program of propeller was made with loworder surface panel method. The energy saving effect of commutated fin, prepositioned duct, and compensating duct was predicted. The calculation result shows that this method is feasible to predict the energy saving effect of energy saving devices. The efficiency of the propeller is improved remarkably when the three types of energy saving devices are installed. Related Articles | Metrics

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Parametric Design and Application of Inlet Duct of Marine Waterjet DING Jiangming，WANG Yongsheng 2010, 44 (10):  1423-1428.  Abstract ( 4220 )   Save In order to design an outstandingperformance inlet duct of marine waterjet in a quick and effective way, a parametric design method was introduced in this paper. In this method the 3D configurations of the inlet duct was characterized with sixteen governing parameters. The lip at the intake and the boundary region between ramp and hull were established with Bezier curves, where the flow changed sharply. The sixteen governing parameters were associated mutually. If one parameter changed, the other parameters could be adjusted automatically in consequence according to the relationship among them, which made it possible to create or modify accurately the inlet duct structure in a fast and flexible way. Then the hydrodynamic performance of the inlet duct was analyzed in the round by means of computational fluid dynamics, on the ground of which analysis results of the configuration of the inlet duct was modified in reason. Iterative usage of the parametric modeling of inlet duct geometry and the hydrodynamic performance evaluation by means of computational fluid dynamics simulation could result in an excellent inlet duct design in a fast way. And the parametric design method was applied successfully to redesign the inlet duct of a waterjetpropelled craft. Related Articles | Metrics

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Stern Form Optimization Aimed at Wake Uniformity FU Huiping，CHEN Zuogang 2010, 44 (10):  1429-1433.  Abstract ( 3397 )   Save Method of stern form optimization aimed at improvement of wake nonuniformity was researched. A 3 100 TEU container ship was taken as initial hull in the optimization process. Based on the module of Framework imbedded in the CFD code Friendship, the two modified afterbodies were created. The preprocessed code of FLUENT, GAMBIT, was used to produce the mesh. Based on the uniform mesh form, the flow fields around three hull forms were numerically simulated. Hydrostatic parameters, resistance coefficients and wakes were analyzed. Through the numerical feature of section shape, x-i, the degree of U, V shape of hull form was also analyzed. The results show that the larger the section number where the value of max(x-i) arise, the better the wake uniformity. From stern to bow, the section number increases. The value of x-i should be lower as it gets closer to the stern. By adapting the after body of hull to extreme U shape section, not only wake peak, wake gradient but also wake nonuniformity is improved apparently, while its resistance increases only 0.61%. Related Articles | Metrics

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Nonlinear Response of Partial Ship Structure Caused by Ultralow emperature 2010, 44 (10):  1434-1438.  Abstract ( 3577 )   Save (1. State Key Laboratory of Ocean Engineering, Shanghai Jiaotong University, Shanghai 200030, China; 2. Shanghai Rules and Research Institute, China Classification Society, Shanghai 200135, China) The insulation of liquefied natural gas (LNG) carrier is wooden boxes filled with perlite and thin steel plate. The property of wood is not very stable. During 40 years of ship’s enlistment, all loads act on the insulation. The boxes would be destroyed and perlite powder would leak out. Then the LNG pressure can pierce through the thin steel plate easily. As a result, ultralow temperature would act on ship structure immediately. So three possible accident models were assumed for that problem. Considering material property changes with temperature, a research on the nonlinear response of partial structure of LNG carrier was conducted by using MARC software. Then the action of heat capacity on structure response was studied and a theoretical design of structure protection was proposed. Key words： liquefied natural gas (LNG) carrier; nonlinear response; thermal Related Articles | Metrics

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A Method to Improve the Accuracy of Videobased Vehicle Speed Measurement ZHANG Zhongde,ZHANG Chongwei 2010, 44 (10):  1439-1443.  Abstract ( 3405 )   Save With an analysis of the insufficient accuracy of the video based vehicle speed measurement based on virtual lines, a method was proposed to improve the measurement accuracy. A rectangle detection area was defined on a road lane, but it was displayed as a trapezoid on the images captured by the video camera. By using twodimensional image calibration transformation, the image coordinates of any point within the trapezoid area could be accurately mapped to the ground coordinates of corresponding point within the rectangle area. By selecting adequate image frames captured during the vehicle running across the detection area, the displacements of the vehicle and corresponding time intervals could be obtained by the proposed algorithm and thus the vehicle speed could be achieved with better accuracy. Related Articles | Metrics

Engineering Mechanics

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A New Fatigue Theory Based on Fatigue Characteristic Length HOU Shanqin1,2，XU Jinquan1 2010, 44 (10):  1444-1449.  Abstract ( 3516 )   Save A new fatigue theory was proposed by introducing the concept of fatigue characteristic length to deal with the weakness of current fatigue evaluation method. The theory is a unified evaluation method to fatigue problems regardless of the nature and size of the defects. It can also give a reasonable explanation of the sizeeffect on fatigue properties, and meet the gap between fatigue limit strength and crack propagation threshold. By considering the fatigue behavior of the material within the characteristic length, it is observed that there are intrinsic relationships among the SN curves, the εN curves and the Paris law. Compared with the experimental results, the evaluation results based on the present theory agrees well with the empirical results of materials not only with or without defect, but with crack fatigue propagation. Related Articles | Metrics

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Experimental Study on Deformation and Shock Damage of Small Target Subjected to Underwater Explosions LI Liangjun1，JIANG Weikang1，AI Yanhui2，TONG Zhiyong2 2010, 44 (10):  1450-1455.  Abstract ( 3429 )   Save Cylindrical shell is the key part in ships and offshore structures, and accurate prediction of the dynamic response and shock damage of the cylinder model makes good sense. In this paper, a cylindrical shell consisting of twin cavities was designed to simulate the structure with stuffing, which is called hard model compared with the soft model without sand inside. The dynamic responses and shock damages of the test models subjected to underwater shock wave loadings detonated by spherical TNT explosives were investigated. Different tests were conducted by changing the TNT charge weight, standoff distance, explosion position and model type. Furthermore, the experimental results are compared. Detailed discussions on experimental results show that the dynamic responses and damage modes are much different; the hard cylindrical shell has better resistance than the soft one when exposed to underwater explosion. The shock damage is mainly observed at the instrument capsule of the hard model while the main capsule of the soft one manifests axial tearing of the shell. Related Articles | Metrics

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Threedimensional Numerical Simulation for Blast Response of Double Laminated Insulating Glass Curtain Wall DENG Rongbing1，JIN Xianlong1,2，CHEN Jun3 2010, 44 (10):  1456-1459.  Abstract ( 3904 )   Save A threedimensional finite element model for blast response of double laminated insulating glass curtain wall was constructed. The whole blaststructure coupling model took into account the air layer between glass plies and supporting components representing real blast environment. The whole process from explosive detonation to response of curtain wall was reproduced on a high performance computing platform. The dynamic behavior of glass unit in the curtain wall under blast loading was analyzed and the numerical results were found to be in agreement with the experiment. The results provide reference for the blast resistance design and improvement of curtain wall system. Related Articles | Metrics

Ocean Engineering

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Control Strategy for Horizontal Vibration of Towed Seismic Cables via Lyapunov Method LIU Tao,ZHANG Weijing，MA Jie 2010, 44 (10):  1460-1464.  Abstract ( 3328 )   Save This paper presents the active vibration control of the towed seismic cable through a bird. A linear partial differential equation with variable coefficient describes towed seismic cable and an ordinary differential equation describes the dynamic of the bird. A control law is designed based on Lyapunov method, and the whole system’s energy is chosen as Lyapunov function. The control law includes the velocity and the slope. Finally, finite difference scheme is used to validate the efficiency of the control law. Related Articles | Metrics

Mathematics

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Stability of Interative Procedure of the Strict Asymptotically Quasi Pseudocontractive Mappings ZHANG Yunliang 2010, 44 (10):  1465-1469.  Abstract ( 3887 )   Save By introducing the concept of strictly asymptotically quasipseudocontractive mappings, the stability of the Ishikawa iterative processer for asymptotically nonexpansive mappings in the intermediate sense and strictly asymptotically quasipseudocontractive mappings in arbitrary real Banach spaces were investigated. Our results improved and extended the recent corresponding results. Related Articles | Metrics

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Statistical Analysis of Scientific Papers of Shanghai Jiaotong University Between 1999 and 2008 HE Xianmei，SHEN Xiaoyun，MOU Yuping，LIU Nannan 2010, 44 (10):  1470-1476.  Abstract ( 3708 )   Save Science Citation Index (SCI), Engineering Index (EI) and Index to Scientific and Technical Proceedings (ISTP) are internationally distinguished retrieval systems which are globally recognized systems for statistical analysis of scientific papers. By means of these systems, and along with MEDLINE and CSTPCD (Chinese Science and Technology Papers and Citation Databases), the scientific papers of Shanghai Jiaotong University cited by SCI, EI, ISTP, etc. between 1999 and 2008 were statistically analyzed. It was found that during this period, the scientific papers of Shanghai Jiaotong University increased dramatically and the quality of the papers improved greatly. However, compared with Tsinghua University and Harved University, Shanghai Jiaotong University still has a long way to go in increasing both the quantity and the quality of scientific papers, thus, some suggestions were proposed. Related Articles | Metrics

Others

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Statistical Analysis of Scientific Papers of Shanghai Jiaotong University Between 1999 and 2008 HE Xianmei，SHEN Xiaoyun，MOU Yuping，LIU Nannan 2010, 44 (10):  1470-1476.  Abstract ( 2284 )   Save Science Citation Index (SCI), Engineering Index (EI) and Index to Scientific and Technical Proceedings (ISTP) are internationally distinguished retrieval systems which are globally recognized systems for statistical analysis of scientific papers. By means of these systems, and along with MEDLINE and CSTPCD (Chinese Science and Technology Papers and Citation Databases), the scientific papers of Shanghai Jiaotong University cited by SCI, EI, ISTP, etc. between 1999 and 2008 were statistically analyzed. It was found that during this period, the scientific papers of Shanghai Jiaotong University increased dramatically and the quality of the papers improved greatly. However, compared with Tsinghua University and Harved University, Shanghai Jiaotong University still has a long way to go in increasing both the quantity and the quality of scientific papers, thus, some suggestions were proposed. Related Articles | Metrics