Table of Content

30 October 2012, Volume 46 Issue 10 Previous Issue    Next Issue

Architechural Science

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Embedding Construction Sequence Knowledge into IFC-CAD Model SONG Yuan-Bin, XU Feng, HU Hao 2012, 46 (10):  1539-1543.  Abstract ( 2520 )   Save Automatic generation of construction sequence from CAD model is a prerequisite for evaluating constructability of capital projects. Unfortunately, traditional studies for deriving construction sequence can not adequately capture or incorporate some necessary concurrency relationships. This paper proposed a new concept of construction state, and uses 14 types of interval-to-interval temporal relationships, resulting in that both precedence and concurrency relationships can be semantically depicted. Moreover, this paper further developed two types of construction sequencing knowledge: state chain type for a single building component and state interaction type for two components. Both knowledge types, which can be represented using Express language, are compatible with the IFC standard, and can also be embedded into IFC-CAD model. References | Related Articles | Metrics

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Deformation Characteristics of Non-homogeneously Saturated-Unsaturated Soils ZHANG Xiao-tong, ZHENG Dong-sheng, XIA Xiao-he, WANG Jian-hua 2012, 46 (10):  1544-1547.  doi: 10.16183/j.cnki.jsjtu.2012.10.002 Abstract ( 2853 )   HTML ( 482 )   PDF (510KB) ( 589 )   Save A fully coupled numerical model was presented to analyze the process of dissipation of the excess pore water pressure and solid skeleton deformation based on the poroelastic governing equations. The numerical model was verified against a two-dimensional consolidation of homogeneous unsaturated soil. The numerical results show that the non-homogeneity has its own importance not only during the process of dissipation of the excess pore water pressure but also for solid skeleton deformation. As the gradient of soil modulus increases, dissipation rate of excess pore water pressure increases and the amplitude of the soil's deformation decreases in the initial compaction stage and final steady stage. Figures and Tables | References | Related Articles | Metrics

Architechural Science

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Numerical Simulation on Mechanism of Soil Retaining Wall Reinforced with H-V Inclusions by DEM ZHOU Huai-1, 2 , ZHANG Meng-Xi-1 2012, 46 (10):  1548-1552.  Abstract ( 3101 )   Save Soil reinforced with horizontal-vertical (H-V) is a new concept of reinforced soil. A series of laboratory model tests of soil retaining wall reinforced with H-V inclusions were investigated and the particle flow code (PFC), based on the discrete element method (DEM), was used to simulate the model tests. The facing displacements and lateral earth pressures acted on vertical elements from PFC numerical simulations were compared with the results of model tests. Meanwhile, the mechanism and failure surface of soil retaining wall reinforced with H-V inclusions were investigated by the displacement and stress field of PFC ball units. References | Related Articles | Metrics

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Dynamic Response of the Sandy Seabed to Combined Wave and Current Loading CUI Song, ZHENG Dong-sheng, YE Guan-lin, XIA Xiao-he, WANG Jian -hua 2012, 46 (10):  1553-1557.  doi: 10.16183/j.cnki.jsjtu.2012.10.004 Abstract ( 2328 )   HTML ( 10 )   PDF (496KB) ( 592 )   Save Based on two-phase u-p theory for saturated soil, a new constitutive model based on the super/ sub-loading surface and anisotropy was utilized to analyze the dynamic responds of a sandy seabed under the combined wave and current loadings. Firstly, a poro-elastoplastic model for a sandy seabed was established. The mechanics of oscillatory excess pore water pressure in seabed and residual excess pore pressure due to wave/ current were discussed and the liquefaction depth which changes correspondingly was obtained. A comparison between the elastic and elatoplastic sandy seabed's dynamic responds to wave/current loading was also presented. Figures and Tables | References | Related Articles | Metrics

Architechural Science

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Channel-Type Technique of Earthwork for Top-down Excavation and Its Application XU An- Jun 2012, 46 (10):  1558-1562.  Abstract ( 3357 )   Save A channel-type technique of earthwork was presented to resolve the conflict between the earthworks and struts construction in top-down excavations. In the new construction method, a working channel is cut in the middle of the excavation area at first. The remained soil on both sides of channel is quickly excavated in segmentation and transported through the channel. The strut system is constructed at the same time. Comparing to traditional excavation technology, the new method can not only promote the working efficiency and shorten construction time, but also reduce the deformation of retaining structures and surrounding environment. It is successfully applied in Shanghai West Railway Station project of Metro line #15. The deformation of diaphragm is controlled within permitted value, and the efficiency of construction is improved about 40% comparing to traditional method. Key words： References | Related Articles | Metrics

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Research of Loading-Rheological Test on WUXI Silty Clay Buried in Different Depth DING Wen-Qi-1, 2 , WANG Chun-Bo-1, 2 , WANG Jun-3 2012, 46 (10):  1563-1569.  Abstract ( 2380 )   Save Studies on rheological properties of silty clay buried in different depth under different consolidation method and different loading method by setting the principal stress axes in the horizontal and vertical direction were carried out subject to ③2 layer silty clay and ⑥2 layer silty clay in WUXI district, and the rheological equation of generalized Kelvin model and Burgers model under triaxial stress state was derived. The test results fit very well with Burgers model. The test shows that the rheological deformation rate of silty clay buried in the same depth increases with the increase of deviatoric stress, but when the deviatoric stress increases to a certain value, the rheological time is very short and does not maintain the phase of rheological deformation. The rate of rheological deformation and rheological threshold are bigger than that of depth smaller, and the time of rheological deformation to stability is shorter for the same type of soil. By the influence of soil anisotropy, the rheological model parameters vary with the different loading modes, but the model parameters increase with increasing confining pressure. References | Related Articles | Metrics

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Experimental Study on the Effect of Loading Rate for Dynamic Fracture Toughness of Rock GONG Neng-Ping, LUO Yu-Fan, GAO Yuan 2012, 46 (10):  1570-1572.  Abstract ( 2658 )   Save By using CCCD-SHPB (central cracked circular disksplit Hopkinson pressure bar) test system  the pure type Ι loading tests of granite samples under different loading rate were carried out, the relationship between the average loading curvesP(t)and time was measured. The things gained above are used in the promoted central cracked circle disk specimen stress intensity factors calculation formula to obtain the dynamic fracture toughness of the granite under different loading rates and reveal the relationship between loading rate and dynamic fracture toughness. The results show that in the loading rate range from 50 to 350 GPa·m1/2/s, the fracture toughness has a linear upward trend with the increase of loading rate.   References | Related Articles | Metrics

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Limit Analysis for Reinforced Concrete Beams with Rectangular Cross-Section under Bending and Torsion   CHEN Xi-a, LIU Xi-La-b 2012, 46 (10):  1573-1580.  Abstract ( 3498 )   Save A new limit analysis method for rectangular reinforced concrete (RC) beams subjected to combined bending and torsion was given. Based on the warped failure surface determined by external loads, with an assumed reasonable stress distribution, a new strength equation on torsion-bending interaction was derived from the equilibrium conditions, which should be a lower bound in limit analysis. The new equation is simple and conceptually clear. Comparing with the existing test results it is shown that the new method is in good agreement with the existing test results, and may also be used in more complex external loadings case.   References | Related Articles | Metrics

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Bond-Slip Deterioration Model of Corroded Reinforced Concrete Members under Reversed Cyclic Loading YANG Shu-Yan, LIU Xi-La 2012, 46 (10):  1581-1586.  Abstract ( 3255 )   Save Based on published bond-slip model of reinforced concrete member under low frequency reversed loading, a new one with corroded reinforcement was established. The new model corrected some relative parameters theoretically in the mesoscale, such as cyclic bond-slip envelope, adhesive stress factor, frictional stress factor, reversed stress, residual stress and corresponding slip value. Comparing with the existing test results, it shows that the new model is viable in practice. The obtained results are very significant for evaluation of aseismatic behavior of corroded reinforcement elements. References | Related Articles | Metrics

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Numerical Simulation of Wind-induced Vibrating Responses of  Typical Composited Spatial Membrane Structures   CHEN Ya-Nan, CHEN Yi-Ran, ZHOU Dai, SUN Ying-Hao, MA Jin 2012, 46 (10):  1587-1593.  Abstract ( 2588 )   Save The numerical simulations of the wind-induced responses of the spatial membrane structures with mountain-like shape were investigated. The windinduced responses of the structure such as displacement, velocity and acceleration were numerically evaluated by considering various coming wind velocity and open-/closed-type topping caps. The obtained results show that the maximum structural displacements caused by the wind are almost identical for both structural systems with open-type and closed-type topping caps. For the structure with closed-type topping cap, the maximum acceleration is greater than that of the one with open-type one, whereas its transient amplification coefficient of structural displacement is smaller. With the increased wind velocity that falls within a certain range, it is also found that the vertical displacements of the structure with open-type topping cap increase while its transient amplification coefficient changes little. The current investigation in brief will be helpful for the wind-resistance design of this kind of spatial membrane structure.   References | Related Articles | Metrics

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Risk Evaluation Method of Deep Excavation Considering Multi-parameter Correlation LIU Yi-jie, CHEN Jin-jian, WANG Jian-hua, ZHU Yan-fei 2012, 46 (10):  1594-1598.  doi: 10.16183/j.cnki.jsjtu.2012.10.011 Abstract ( 3327 )   HTML ( 11 )   PDF (642KB) ( 810 )   Save A new risk evaluation method of deep excavation was presented by considering the correlation of multiple parameters. The load transfer and deformation of retaining structure and surrounding soil were analyzed to discuss the correlation mechanism of different parameters during deep excavation. The quantitative relationship among these parameters was determined by the statistical analysis. A multi-parameter risk evaluation method and software were then proposed based on the correlation analysis of multiple parameters. The presented method was applied in a case of metro station in Shanghai. The results show that some risk during construction which can not be warned by the traditional methods is found in the new method. Figures and Tables | References | Related Articles | Metrics

Architechural Science

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Experimental Study on Characteristic of Thermal Energy Storage Defrosting for Air Source Heat Pump Using Sub-cooling Energy of Refrigerant DONG Jian-Kai-1, JIANG Yi-Qiang-1, YAO Yang-1, YAN Ling-2 2012, 46 (10):  1604-1608.  Abstract ( 2781 )   Save This study is concerned with a thermal energy storage defrosting (TESD) based on reverse cycle defrosting method for air source heat pump (ASHP) using subcooling energy of refrigerant to eliminate frost on surface of outdoor coil. The feasibility of thermal energy storage using sub-cooling energy of refrigerant and defrosting were investigated experimentally. The defrosting performances were compared with a normal 850 W capacity ASHP system standard reverse cycle defrosting (SRCD) method. The results indicate that by the TESD for ASHP using sub-cooling energy of refrigerant method, the system coefficient of performance in heating can be improved due to the sub-cooling of refrigerant outlet of indoor coil, defrosting duration and reheating time can be shortened, and the indoor thermal comfort can be improved when defrosting and re-heating. During defrosting duration, TESD for ASHP using sub-cooling energy of refrigerant method improves discharge and suction pressures by 0.57 MPa and 0.11 MPa, respectively, also shortens defrosting duration and re-heating time by 30.8% and 25% in the tested environment, and reduces defrosting power consumption by 22.8kJ, relative to the SRCD method.   References | Related Articles | Metrics

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Experimental Study of Ultrasound Atomization Dehumidifying System  with Liquid Desiccant 2012, 46 (10):  1604-1608.  Abstract ( 1820 )   Save The dehumidification efficiency of the ultrasound atomization dehumidifying system with liquid desiccant was studied experimentally. The effects of quality concentration of calcium chloride and lithium chloride mixture solution, liquidair ratio and air-liquid reaction time were analyzed according to the experimental data. It is found that the dehumidification efficiency of this system is 18.1%~26.9% under 9 groups of experimental conditions; the efficiency decreases when the salt quality concentration decreases from 38% to 35%; the liquidair ratio greatly affects the dehumidification efficiency, which increases 50% when the liquid-air ratio increases from 0.18 to 0.84; increasing the reaction time helps improve the efficiency. Moreover, the temperature of the processed air is raised when the efficiency increases.   References | Related Articles | Metrics

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Dynamic Similarity Analysis and Experimental Verification on a Quayside Container Crane   JIN Yu-Long, WU Tian-Xing 2012, 46 (10):  1609-1615.  Abstract ( 2565 )   Save Based on the dynamic similitude theory, a detailed deduction process on the similarity scale factors between the prototype and 1∶50 scale model was presented. A hammering modal test and a series of seismic shaking table tests were successively carried out to obtain the dynamic characteristics and the seismic responses of this 1∶50 scale model. Meanwhile, the corresponding dynamic behaviors of the prototype were also systematically analyzed by the use of the ANSYS software. The investigation results indicate that the 1∶50 scale model can accurately predict the dynamic performances and seismic responses of the prototype with small error and can provide a reliable testing model for the following studies.   References | Related Articles | Metrics

Metallography and Metallurgical Technology

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3D Die Shape Optimization Technology for Net-Shape Forging of Aerofoil Blade SHAO Yong-1, 2 , LU Bin-1, Hengan Ou3, CHEN Jun-1, GUO Ping-Yi-2 2012, 46 (10):  1616-1621.  Abstract ( 3247 )   Save A precise simulation for net-shape forging process of aerofoil blade including flash trimming operation was investigated and a direct surface compensation method for 3D optimization design of die shapes was proposed in terms of dimensional and shape tolerances of aerofoil cross-sections emergence during forging process.Quantitative representations of aerofoil forging tolerances were established to provide a correlation between conventional dimensional and shape specifications in forging production and those quantified in FE simulation. A new algorithm employing variable weighting factors to minimize the total forging tolerances in forging optimization computations was proposed to calculate compensation quantities of die surface nodes. A surface approximation using a B-spline surface was also developed to ensure improved die surface quality for die shape representation and design. For a Ni-alloy blade test case, substantial reduction in dimensional and shape tolerances was achieved using the developed die shape optimization system. References | Related Articles | Metrics

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Bounded Intensity Process and Its Applications in Reliability Assessment of NC Machine Tools WANG Zhi-Ming-1, YANG Jian-Guo-2 2012, 46 (10):  1622-1626.  Abstract ( 3172 )   Save Based on Akaike information criterion, Bayesian information criterion and the root-mean-square error of the fitting failure data, the best non-homogeneous Poisson process model of reliability analysis for repairable system was proposed. The point maximum likelihood and interval estimators of the parameters, as well as the reliability indices of the bounded intensity process model were given using the asymptotic lognormal distribution of the maximum likelihood estimation and the Fisher information matrix method. The failure data with time truncation of multiple NC machine tools were analyzed. The results show that the bounded intensity process is suitable for reliability assessment of deterioration machine tools with frequent maintenance actions. References | Related Articles | Metrics

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Plastic Deformation Characteristics of 20CrMnTiH Gear Steel under High Temperature HU Cheng-Liang, ZHANG Ying, ZHAO Zhen, LI Shi-Long, ZHI Yue-Sheng 2012, 46 (10):  1627-1631.  Abstract ( 2907 )   Save Taking the 20CrMnTiH gear steel as an object, under the condition of deformation temperature of 850 °C-1 150 °C and strain rate 0.01 s-1-10 s-1, different high temperature compression tests were carried out to investigate its plastic deformation characteristics. The flow stress under 850 °C is 2 to 3 times  the stress under 1 150 °C, and the stress at strain rate 10 s-1 is 2 to 3 times  the stress at strain rate 0.01 s-1. Under high temperature and low strain rate, the phenomenon of continuous dynamic recrystallization (CDRX) takes place. From the microstructure, the recrystallized grains along initial grain boundaries grow and new grains generate with the increase of deformation temperature, and the grains grow up significantly because of CDRX when the temperature is 1 050 °C. The hot deformation activation energy of the steel is 371.053 kJ/mol. Based on the processing map, the optimum processing parameters of hot deformation are obtained, that is,  the deformation temperature is 1 020 °C-1 150 °C and the strain rate is 0.5 s-1-2.5 s-1. Key words： References | Related Articles | Metrics

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Strain-Controlled Fatigue Properties at Room Temperature of a High-Speed Matrix Steel Used as a Cold Forging Tool Material   ZHANG Ying-1, HU Cheng-Liang-1, ZHAO Zhen-1, LI Ai-Ping-2 2012, 46 (10):  1632-1636.  Abstract ( 2464 )   Save Static uniaxial tension experiment and strain-controlled tension-compression fatigue experiments were conducted at room temperature to cold forging tool material, a matrixtype high speed steel. Mechanical property parameters under static tension and low cycle fatigue loading conditions were acquired through the experiments. Static monotonic tension strain-stress relationship, cyclic strain-stress relationship and cyclic strain-life relationship of the steel at room temperature were derived from regression of the experiment data. The experimental results show that cyclic softening happens to the tool material at all levels of controlled cyclic strain amplitudes in this study. No visible stress saturation is observed before fatigue failure occurrs. A specimen at the controlled strain amplitude of 1.5% was used as an example to investigate the LCF behavior characteristics of this material. The cyclic stress response shows a variation with three stages: the obvious softening stage, the slow softening stage and the final rupture stage. References | Related Articles | Metrics

Astronomy,Geoscience

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Sensitivity Analyses for Time-Domain Fatigue Life of Umbilical Bending Stiffener WANG Ai-Jun, YANG He-Zhen 2012, 46 (10):  1637-1641.  Abstract ( 2572 )   Save Nonlinear characteristic of bending stiffener made from polymer is obvious and traditional fatigue analysis method in frequency domain is not applicable. Fatigue strength is the crucial and difficult aspect of bending stiffener design. Mathematical model for bending stiffener analysis was established, and fatigue analysis method of bending stiffener based on mathematical model was introduced. Fatigue analysis in time domain employs the thought from global analysis to local analysis. Then sensitivity analysis was performed to study the effects of different parameters on fatigue life of bending stiffener, and the effects of different parameters were discussed. The method proposed in this work and the conclusions can be the guide for bending stiffener of deepwater umbilical design.   References | Related Articles | Metrics

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Study on the Wind Tunnel Testing of Air Cushion Effect of High-Speed and Long-Runout Landslide XING Ai-Guo-1, YIN Yue-Ping-2, QI Chao-1, ZHANG Ming-3, HUANG Han-Jie-4, HAN Jin-Liang-3 2012, 46 (10):  1642-1646.  Abstract ( 2890 )   Save Many high-speed and long-runout landslides could fly in the air at the start-range stage, which has a significant effect of aero-dynamics. A wing model which is similar to sliding mass and a wing tunnel testing are made to determine the influence of aerodynamic effect and aerodynamic parameters. In the testing, valley terrain with different slopes and cross-sections can be made of wooden material. The results of wind tunnel testing show that aerodynamic properties of high-speed landslide are significant by the air cushion effect. Because of the different valley terrain, lift coefficient will dramatically increase when the around mountains get to closer. Therefore, vertical lift of high-speed sliding mass is increased, but it’s not obvious in flat terrain. The variations of lift-drag ratio in different valley terrains are basically the same, and the maximum values happen when angles of attack equal to 8°. References | Related Articles | Metrics

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Three-satellite Positioning Algorithm with Altitude Aiding for Regional Navigation Satellite System WANG Meng-a, b , MA Li-Hua-a, ZHANG Li-Rong-a, JI Hai-Fu-a, b , SHI Hu-Li-a 2012, 46 (10):  1647-1651.  Abstract ( 3007 )   Save An altitude aiding positioning algorithm not constrained by altitude was proposed for the regional navigation satellite system (RNSS). The algorithm does not require construction of the approximate ellipsoid equation or the preceding position information. The key point of the algorithm is iteratively improving the virtual range from the earth center to the estimated position in processing of Newton’s method. The virtual range is combined by the measured altitude with the approximate latitude and longitude.  In order to evaluate the performance of the proposed algorithm, a simulation analysis was performed based on the Chinese area positioning system (CAPS) in the verification phase. And the results show that the proposed algorithm can provide positioning at any altitude level from the ground to medium earth orbit (about 12 000 km).With the analysis of the dilution of precision matrix for the altitude aiding algorithm, formulas of the error ellipse’s axial length and direction were proposed. The simulation results show that the formulas can describe the error ellipse geometric characteristic accurately.   References | Related Articles | Metrics

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Numerical Simulation of Hydropneumatic Tensioner for Coupled Deepwater Platform System WANG Kun-Peng, XUE Hong-Xiang, TANG Wen-Yong 2012, 46 (10):  1652-1657.  Abstract ( 2653 )   Save The hydropneumatic tensioner used for the connection of deepwater platform and top tension risers (TTRs) was studied based on the hull/mooring/riser coupled analysis program developed in ABAQUS. The present study focused on the challenges for the tensioner numerical simulation, and proposed a nonlinear tensioner model considering the nonlinear stiffness, friction and the connection of platform, tensioner and TTR. The tensioner is simplified as a linear model, and the predicted responses are compared with that of nonlinear model, from which the effect of nonlinearity on the risers and platform is obtained, which would contribute to more accurate predicted ultimate strength and fatigue life. References | Related Articles | Metrics

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Semi-Dynamic Modeling and Simulation Study of Underwater Faired Cable WANG Fei, HUANG Guo-Liang 2012, 46 (10):  1658-1664.  Abstract ( 2627 )   Save This paper presented a 4-DOF semi-dynamic mathematical model for the dynamics of underwater faired cable, which is used to study the macroscopical dynamics through numerical simulation method. To model the faired cable’s dynamics suitably, its motions were analyzed and resolved into 3-DOF dynamic translational motions and 1-DOF steady state rotary motion about cable axis according to its kinematic characters, then the governing equations were developed based on the above and the principle of lumped parameter method. This model can account for cable weight, buoyancy, hydrodynamic forces as well as torsional moments, which is numerically solved by 4th order Runge-Kutta integration method. Some numerical examples were given to study its dynamics, and some useful conclusions were drawn.   References | Related Articles | Metrics

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Dynamics Analysis of Niujuangou Rockslide-Debris Avalanche Triggered by the Wenchuan Earthquake ZHANG Yuan-Jiao-1, XING Ai-Guo-1, ZHU Ji-Liang-2 2012, 46 (10):  1665-1670.  Abstract ( 3735 )   Save Niujuangou rockslide-debris avalanche is known as a typical rockslide-debris avalanche, which was triggered by the Wenchuan earthquake. Superposed earthquake effects came from horizontal and vertical directions made initial rock mass throw out and move rapidly, after experiencing several strikes, rock mass almost fragment, and sliding mass move like debris avalanche in Niujuangou creek. A dynamic model DAN was used to back analysis of this event. Both Friction rule and Voellmy rule were modeled and compared. The results show that it would be best to adopt Friction rule in the proximal path and Veollmy rule in the distal path. And most suitable parameters, volume and profile of deposition, velocity of sliding mass were obtained. References | Related Articles | Metrics

Hydraulic Engineering

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The Risk Probability Analysis on Design Combination of Wind Wave and Tidal Level in Design of Sea Dike YANG Xing-1, LIU Zhi-Long-2, WU Su-Shu-1, LI Zhi-Qing-1, LI Chao-Fang-2 2012, 46 (10):  1671-1674.  Abstract ( 3306 )   Save Wind wave and tidal level are the crucial factors in the design of sea dike project. To balance the engineering cost and engineering safety, an approach was applied to design the combination of wind wave and tidal level with risk consideration. A combined distribution function was built by using Clayton Copula, thereafter, the wind wave and wind level combination risk design model was established. Observed hydrological data on Shenzheng Chiwan area from 1971 to 2002 were analyzed to obtain the combined risk probability of wind wave and tidal level. The results indicate that the probability is low when high wind wave reaching high tidal level, and the model puts the risk probability into consideration, which provides a reasonable method for coastal sea dike design.   References | Related Articles | Metrics

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Establishment of Sea Wall Seepage Pressure Multi-point RBF Monitoring Model HUANG Ming-1, LIU Jun-2 2012, 46 (10):  1675-1679.  Abstract ( 2443 )   Save In order to establish multi-point sea wall seepage pressure monitoring model to describe its rules considering tidewater etc., radial basis function (RBF) artificial neural network was used together with sea wall seepage pressure effect factors analysis. Former tidewater factor, integral rain factor and time effect factor were put into the network as input units, while multiple suitable seepage pressure survey points were taken as output units together. Furthermore, the method to pre-select RBF center considering sea wall seepage pressure character was studied. Then fuzzy C-means algorithm (FCM) was used to adjust and decide them. The instance of Pudong sea wall shows the process of establishing seepage pressure multi-point RBF monitoring model which has good results. Suggestions of application were presented also. References | Related Articles | Metrics

Communication and Transportation

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Data Preprocess for Bridge Damage Alarming System CHEN Ming 2012, 46 (10):  1680-1686.  Abstract ( 2365 )   Save  Bridge alarming system data sets are often interspersed with noise. If it does not consider noise, the data process algorithm in alarming system may not provide accurate results. A new hybrid approach comprising of neural rules, data classification and data evaluation was proposed to carry out data selection. Specifically, the neural rules remove noise data by applying the principles of an intelligent reasoning process. Data classification classifies the patterns in the reduced datasets based on the similarity index. The data evaluation applies curvature model to extract kernel information of bridge structure. The simulation results demonstrate that the proposed approach produces good classification accuracy and a higher level of consistency to bridge damage condition. References | Related Articles | Metrics

Mathematical sciences and chemical

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Application in 2D Solid Analysis of General Inverse Matrix-Based Large Increment Method LONG Dan-Bing-a, LIU Xi-La-b 2012, 46 (10):  1686-1692.  Abstract ( 3266 )   Save To extend the application of large increment method (LIM) into 2D solid analyses, a 4-node quadrilateral element which adapts to LIM was proposed. Two numerical examples were solved  using the new element. The mesh convergence and the insensitiveness to the mesh distortion are proved, and the advantage of parallel computation is implied.   References | Related Articles | Metrics

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A New Finite Difference Method for Rosenau-Burgers Equation SHAO Xin-Hui, XUE Guan-Yu, SHEN Hai-Long 2012, 46 (10):  1693-1696.  Abstract ( 3080 )   Save From the study of the dynamic systems, this paper discussed the numerical method of the initial-boundary value problem of Rosenau-Burgers equation. It reveals the dissipation problems of nonlinear wave. By using the mesh method in time and space domain of the equation, a new implicit finite difference scheme of three levels was proposed. And the prior estimate of the solutions was obtained. It was proved that the finite difference scheme is convergent and stable. The numerical experiment indicates that  the scheme is available and  it is easy to implement, and computational time can be economized. The weighted difference scheme has universal significance and it is worth popularizing. References | Related Articles | Metrics

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Godunov Type Scheme Satisfying Three Conservation Laws WANG Zhi- Gang 2012, 46 (10):  1697-1700.  Abstract ( 2419 )   Save  In order to apply Godunov type scheme satisfying several conservation laws for one dimensional hyperbolic conservation laws to multi-dimensional hyperbolic conservation laws, this paper designs a Godunov type scheme satisfying three conservation laws for two dimensional linear advection equation. The numerical experiments show that this scheme has good structure preserving property in long time numerical simulations.   References | Related Articles | Metrics

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A Matrix Column-Transform Solution-Decision Method for the System of Linear Inequalities LIU Dao-Jian-1, 2 , HUANG Tian-Min-1 2012, 46 (10):  1701-1706.  Abstract ( 4270 )   Save With a view to more efficiently solving system of linear inequalities, a special matrix,  imposed basis-point transition matrix, was given together with  a special negative pivoting iteration operation, by which it can be better displayed that system of linear inequalities has both linear feature and geometric-plane feature. Moreover, based on the above platform, a new solution-decision method for system of linear inequalities was proposed. With the help of this new method, the solutiondecision process of system of linear inequalities can be changed into a series of elementary column transformations of matrixes. So, this method not only works fast and simply but also can be more easily translated into programs and more efficiently accomplished on computers. In addition, a simplex locally ε regularized method was proposed so as to overcome the bad effect coming from vertex degeneration, to the vertex transition iteration processes. References | Related Articles | Metrics