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    28 March 2016, Volume 50 Issue 03 Previous Issue    Next Issue
    Equivalent Static Wind Loads on LargeSpan Arched Structures
    MA Ning, WANG Xun, HONG Ronghua, ZHOU Dai, LI Fangfei, MA Jin
    2016, 50 (03):  317-323. 
    Abstract ( 1005 )   Save
    Abstract: Based on computational fluid dynamics (CFD) and the finite element dynamic timehistory analysis method, the timehistory speed of fluctuating wind was simulated by using the numerical method which was used as inlet boundary condition of numerical wind tunnel. Then, nonsteadystate analysis on a largespan arched structure was made by using the FLUENT software to get the timehistory wind loads. Meanwhile, the windinduced vibration response was analyzed using the ANSYS software. After that, equivalent static wind loads (ESWL) based on timehistory response were obtained and the definition of multiobjective ESWL combination factors was proposed. Finally, the multiobjective ESWL of the open largespan arched structure were obtained with their accuracy verified. The study shows that the static response values under ESWL and extreme response values in dynamic analysis are in good agreement.
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    Effect of Deep Underground Water Recharge on Long-Term Settlements of Pile Foundations
    HUANG Yizhang, SHI Yujin, CHEN Jinjian, WANG Jianhua
    2016, 50 (03):  324-330.  doi: 10.16183/j.cnki.jsjtu.2016.03.002
    Abstract ( 554 )   HTML ( 694 )   PDF (922KB) ( 408 )   Save

    Artificial recharge in deep strata is an effective method to prevent land subsidence, and make the deep strata upheave to some extent. The pile foundations of elevated road are relatively deep so that the deformation of deep strata will greatly affect the elevated road. Using the numerical method, the elevated pile and the behavior of the surrounding soil at pumping and recharge loads were simulated and its deformation characteristics were discussed based on the coupled theory. The result shows that groundwater pumping can cause a large settlement of elevated road, while the artificial recharge can control the settlement effectively. Regional land subsidence is smaller than the elevated settlement, but the deformation tendency matches the elevated road well. Besides, based on an engineering project, the long-term deformation characteristic of elevated road at underground water recharge was simulated. The study shows that numerical results agree with the filed data, and the deformation characteristics of elevated piles are mainly influenced by deep strata. Using parameter analysis, the basic laws of elevated deformation were obtained, providing reference for the prediction of long-term settlement of elevated piles.

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    Experimental Study of Overconsolidation Behavior of the Upper Shanghai Clays in Lianhua Road
    WU Chaojun, YE Guanlin, WANG Jianhua
    2016, 50 (03):  331-335.  doi: 10.16183/j.cnki.jsjtu.2016.03.003
    Abstract ( 470 )   HTML ( 188 )   PDF (754KB) ( 506 )   Save

    A series of laboratory tests were conducted of intacted samples of the 2nd to 6 th Shanghai clays to investigate fundamental physical properties of successive upper clay layers in Shanghai, and overconsolidation behaviors were studied through a series of standard oedometer tests and triaxial consolidated drained compression tests. Natural water content, initial void ratio, liquid/plastic limit and liquid/plastic index were found to have similar trends of variations with depth change. Due to gentle curvature of the compression curve over the preconsolidation pressure range, the work method proposed by Becker was cited to obtain the yield pressure in oedometer test, which showed that the overconsolidated ratio (OCR) of the 2nd and 6th layers were larger than 2, while those of the 3rd and 4th were about 1.15, and that of the 5th were closed to 1.40. Different characteristics of stress-strain curves in drained triaxial tests of the 2nd to 6th Shanghai clays reflect the distribution of OCR obtained in the oedometer test. The unite study method composed by oedometer and triaxial tests will contribute to further understanding of the overconsolidated behaviour of soft clays with weak structure.

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    Analysis of Effect of InPlane and Transverse Loads on Static Performance of Plates
    LIU Degui, ZHOU Shijun, WANG Ning, YAO Yong
    2016, 50 (03):  336-344. 
    Abstract ( 863 )   Save
    Abstract: Using the energy variation principle, the strain energy expression and static equilibrium differential equation for plates considering the effect of both initial inplane and transverse loads were proposed. Meanwhile, the finite plate element considering the effect of both initial inplane and transverse loads was presented. To verify the finite plate element, the approximate solutions of later transverse load displacement for three typical plates (clamped rectangular plate, clamped and simply supported circular plates) considering the effect of both initial inplane and transverse loads were derived by using the Galerkin method. The later transverse load displacements obtained by the finite plate element agreed well with the approximate solutions. The reliability and efficiency of the presented finite plate element and those later transverse load displacement approximate solutions were verified. Numerical examples show that the bending stiffness of plates are changed when the effect of both the effect of both initial inplane and transverse loads are considered, and that the key physical factors governing the effect of initial loads on the frequencies of plates are the initial loads (both inplane and transverse), thickness and boundary condition etc.
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    Analysis of Distributed Static and Kinematic Indeterminacy of Pretensioning CableStrut Systems
    ZHOU Jinyu, CHEN Wujun, DU Bin, GAO Chengjun
    2016, 50 (03):  345-350. 
    Abstract ( 817 )   Save
    Abstract: An analytical approach to the distributed static and kinematic indeterminacy taking into account the stiffness as well as the topology and geometry was developed for pretensioning cablestrut systems, making it possible to identify the structural system in terms of every component rather than the whole system. Based on the equilibrium matrix theory, the singular value decomposition (SVD) method was adopted to calculate two pairs of orthogonal modes, i.e., the modes of compatible/ incompatible elongations and the modes of compatible/ incompatible loads. Due to the orthogonality that indeed avoids the singularity problem, the proposed approach was applicable to kinematically determinate structures and even kinematically indeterminate structures. It is shown that the distributed static indeterminacy is closely related to the structural robustness theory based on the importance indices and the structural sensitivity theory, while the distributed kinematic indeterminacy can reveal the nodal mobility in every equilibrate configuration. Besides, an algorithm was developed to implement this approach and two examples of cablestrut system were presented to demonstrate its robustness and accuracy.
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    Simulation and Analysis of Wind Pressure and Equivalent Static Wind Loads of MultiBody Structure with Complex Shape
    MA Ning, WANG Xun, ZHOU Dai, ZHU Fei, WANG Zitong, HONG Ronghua
    2016, 50 (03):  351-356. 
    Abstract ( 909 )   Save
    Abstract: Taking the great building “Clouds of Celebration” which is a part of Shanghai World Expo Museum as the object, numerical simulation techniques were utilized to investigate the wind pressure distribution, the gust factors (GFs) and the equivalent static wind loads (ESWL) of the complex multibody spatial structure with consideration of mutual interference of wind fields around surrounding buildings under different incoming wind directions. Besides, the wind pressure nephograms and local zone pressure coefficients were discussed, the gust factors were obtained by means of the peak factor method, and the ESWL were determined, taking the most unfavorable incoming wind directions into account.
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    Elastic Shear Buckling of Corrugated Web Girders with Circular Opening
    QIU Jieyaoa, LI Guoqianga, b
    2016, 50 (03):  357-363. 
    Abstract ( 758 )   Save
    Abstract: In this paper, a study on elastic shear buckling of corrugated web girders with circular openings was conducted. A finite element model was established and the elastic buckling load was obtained through eigenvalue buckling analysis. The influence of diameter of opening, web height, web thickness, the transverse and longitudinal eccentricity of opening on the elastic shear buckling was investigated. Based on lots of finite element numerical analysis, the calculation formula for elastic shear buckling capacity of corrugated web girders with circular opening was derived in the form of reduction coefficient.
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    Analysis of Load Capacity Behaviors of Steel Fiber Reinforced Concrete Piles Through Model Tests
    OUYANG Fang, ZHANG Jianjing, DENG Xiaoning, HAN Jianwei, BI Junwei, DU Lin
    2016, 50 (03):  364-369. 
    Abstract ( 807 )   Save
    Abstract: Static load tests of concrete piles of different diameters with and without steel fiber were conducted to study the bearing capacity, the characteristics of strain, and the damage phenomenon of steel fiber reinforced concrete piles under vertical loads. Strain gauges were arranged along the longitudinal direction of the piles in order to measure the strain. Besides, a comparative analysis of the damage features between the steel fiber reinforced concrete pile and the concrete pile was conducted with the excavated piles after the completion of the tests. It is found that the compression deformation of the concrete pile can be effectively decreased with the steel fiber. The steel fiber reinforced concrete pile of the diameter equal to 7.0 cm has less compression and larger ultimate bearing capacity compared to that of the pile with the diameter equal to 4.5 cm. However, the compression and the ultimate bearing capacity vary little when the diameter of the piles changes from 7.0 cm to 8.0 cm. Moreover, the cracks or damage appear at the bottom or top of these piles, and the crack resistance of the concrete pile is improved with the steel fiber. Based on the results, some suggestions were proposed for the design of the steel fiber reinforced concrete pile.
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    Service Life Prediction of Prestress High Concrete Pipe Piles in Marine Environment
    YUE Zhuwen, LI Jingpei, LI Lin, SHAO Wei
    2016, 50 (03):  370-376. 
    Abstract ( 1006 )   Save
    Abstract: Chlorideinduced reinforcement corrosion is the main factor in marine environment for concrete member. The service life of PHC prestress high concrete (PHC) pipe pile was divided into the initiation period and propagation periods. The initiation period, i.e., the chloride transportation time was calculated by Fick’s 2nd law using the difference method. And an elastic mechanics theory was used to solve the propagation period. The results show that the initiation period and the propagation period present linear and exponent relationship with the cover thickness, respectively. The propagation period is greatly decreased as the mortar layer thickness increases. In addition, the service life can be increased to 3 to 4 times by sealing the inner space. Finally, the calculation accuracy of the initiation period was verified by a 180 days chloride erosion test.
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    Experimental and Numerical Investigations of FormDevelopment of Ethylene-Tetrafluoroethylene Cushion Based on FlatPatterning
    ZHAO Bing, CHEN Wujun, HU Jianhui, QIU Zhenyu, SONG Hao, CAI Jing
    2016, 50 (03):  377-383. 
    Abstract ( 785 )   Save
    Abstract: An equilateral triangle ethylenetetrafluoroethylene (ETFE) cushion model with a side length of 2.5 m was developed based on the design method of flatpatterning. The experimental model was performed with a formdeveloping test, which was controlled and measured combining automatic pressure control, photogrammetry and laser sensor. The whole process of formdeveloping included an inflation from 0 kPa to 2 kPa, a viscoelastic creep under 2 kPa lased for 24 h, and a recovery under 0 kPa within 24 h. Some original parametric data, such as internal pressure values, shapes of upper layer and rises of lower layer were obtained. The stress distributions under different conditions were calculated based on the shapes. Some profound material mechanical properties and structural behaviors, such as elastic deformation, viscoelastic creep and creeprecovery, were revealed via the comparisons of results between experiments and numerical simulations. These results demonstrate the applicability, which will improve the popularization and application of ETFE cushion structure.
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    Numerical Analysis of Air Layer Thickness of Horizontally Enclosed Square Cavity
    HE Fangxiang, ZHAN Shulin, LAI Junying
    2016, 50 (03):  384-388. 
    Abstract ( 905 )   Save
    Abstract: In order to analyze the relatively optimal air layer thickness of the horizontally enclosed square cavity based on its thermal insulation, this paper established a twodimensional numerical model and calculated the radiation and convection heat transfer in the horizontally closed square cavity at different temperature differences and different thermal conductivities of the solid boundary material by using the “Presto!” pressure interpolation scheme and SIMPLE (semiimplicit method for pressurelinked equations) decoupling algorithm. The relative optimal air layer thickness values of the horizontally closed square cavity at different temperature difference and thermal conductivity of the boundary material under a certain condition were obtained from the regression analysis of the results.
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    Experimental and Numerical Study of Wind Drag of Large Containership by Using Open Wind Test in Towing Tank
    LUO Shaozea, b, c, MA Ninga, b, c, HIRAKAWA Yoshiaki, GU Xiechonga, b, c
    2016, 50 (03):  389-394. 
    Abstract ( 982 )   Save
    Abstract: The wind resistance of a large containership is emphasized given the indication of the intent of the International Maritime Organization to the application of the key green ship design and operation index such as the energy efficiency design index(EEDI) and a tendency of the containership maximization nowadays. In this paper, on investigation were conducted and the wind profile was studied and compared with other experiment results from wind tunnel tests to validate the feasibility of the open wind resistance test for the wind resistance measurement in a towing tank. Besides, the wind drag force on a 3 100TEU containership with containers and superstructure was measured in the wind turbine test with a 1.0∶87.5 scale model. Through a series of container layout cases, the difference of the wind drag force was analyzed and simulated by using CFD. It is proved that open wind test is a simple and effective measurement. Through cross validation, the results are proved credible and CFD has the priority in terms of precision and detailed simulation. The wind drag can be reduced through configuration optimization.
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    A Novel BrakebyWire Unit and Control System for Electric Vehicle
    GONG Xiaoxiang, CHANG Siqin, JIANG Lichen, LI Xiaopan
    2016, 50 (03):  395-400. 
    Abstract ( 1129 )   Save
    Abstract: For the characteristics of full electric propulsion on electric vehicle, a novel brakebywire unit, called directdrive electrohydraulic brake unit, was designed to improve the braking performance of electric vehicles based on an electromagnetic linear actuator. A prototype was modified and completed based on a certain type of hydraulic brake unit after the structure and principle of this novel brake unit was described in detail. Then, a braking force controller and a power driver were established based on the digital signal processor TMS320F2812, and a doubleloop antidisturb algorithm was designed to regulate the braking force. The experiment results show that the response time of this brake unit is very short and the brake force is able to be accurately regulated, showing that this brake unit has a good application prospect.
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    Generalized Predictive Control Based on Vehicle Path Following Strategy by Using Active Steering System
    CAO Yang, HE Dengbo, YU Fan, LUO Zhe
    2016, 50 (03):  401-406. 
    Abstract ( 1084 )   Save
    Abstract: In order to improve the lane tracking capability of vehicles under disturbances, an active steering system based on generalized predictive controller was proposed, of which a controlled autoregressive integrated movingaverage model (CARIMA) was used as the inner model. Considering the complexity and uncertainty of vehicle parametric modeling process, a recursive least square method was applied to estimate the parameters in the CARIMA model. The controller used the deviation between the vehicle lateral position and desired lateral positon as the input and steering wheel angle as the output. Based on driver steering wheel input, the final corrected steering wheel angle was obtained. The performances of the controller were examined in the SimulinkCarSim environment under strong lateral wind condition in standard doublelanechange operating experiment.
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    Analysis of Load Characteristics of a Ship in Oblique Regular Waves
    JIAO Jialong, REN Huilong, YU Haicheng
    2016, 50 (03):  407-412. 
    Abstract ( 956 )   Save
    Abstract: Rectangular and cylindrical tubular backbones were used to serve as the backbones of a segmented model for wave load tests. The backbones were designed to meet the stiffness distribution requirements of the model in order to be similar to that of ship prototype. The model was tested in a towing tank in different sea states at different sailing conditions. The results indicate that the segmented model proposed in this paper is capable of simulating the elastic effects of ship sailing in oblique waves. In addition, the threedimensional nonlinear hydroelasticity theory was adopted to calculate the wave load responses of the ship sailing in oblique wave conditions. The comparison of the numerical results and the experimental results shows that the wave loads obtained by the two methods are in good agreement.
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    Traffic Accident Tendency Measurement Method for Drunk Driving Based on Uchida Kraepelin Psychological Test
    ZHONG Mingen, HONG Hanchi, WU Pingdong, FANG Qiu
    2016, 50 (03):  413-418. 
    Abstract ( 859 )   Save
    Abstract: In view of the problem that it might not be reasonable enough to evaluate and punish drunk driving according to the blood alcohol concentration of the driver, 18 drivers were recruited to join the Uchida Kraepelin (UK) test in order to discover a novel method. The results showed that work curves of UK changed significantly from shaped style to unshaped style as the drivers drank successively, together with increasing values of average work mistake rates. These helped to define a work deviation value. Experiments proved that there existed monotonic consistency relationships between work deviation values and traffic accident tendencies, together with an average coefficient of 0.71. Thus, UK work deviation value was able to uncover traffic accident tendencies of drunk driving, and probably could be a new evidence for judging and publishing drunk driving. UK test and its results analysis may be a potential method for measuring traffic accident tendencies of drunk driving.
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    SINS SelfAlignment Algorithm with Inertial Frame for Swaying Base Based on Quaternion
    XUE Haijian, GUO Xiaosong, ZHANG Dongfang, ZHOU Zhaofa
    2016, 50 (03):  419-424. 
    Abstract ( 1250 )   Save
    Abstract: To improve the rapidity and precision of initial alignment for strapdown inertial navigation system (SINS) under swaying base, the SINS selfalignment algorithm with inertial frame for the swaying base based on quaternion was presented, which used attitude update of inertial coordinates to reflect the gesture changes of the carrier under realtime shaking interference. The algorithm transformed the optimal estimation of the initial attitude into the Wahba problem to remove the angular interrupting by quaternion derivation, and used the wavelet denoising threshold to eliminate the linear vibration interrupting according to the different frequency characteristics of gravity vector in inertial reference frame and the disturbance. The simulation results show that the presented method can accomplish the alignment quickly and accurately under swaying base even in the presence of angular motion and linear vibration interference without the coarse alignment process.
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    Vulnerability Check and Further Development of Parametric Roll Criteria of 2nd Generation Intact Stability Code of IMO
    ZHOU Yaohuaa, ZHANG Gaofeng, MA Ningb
    2016, 50 (03):  425-431. 
    Abstract ( 748 )   Save
    Abstract: Based on the research achievements of International Maritime Orgnazation (IMO), sample calculations were conducted for different types of full scale ships. Relations between ship design parameters and vulnerability of parametric rolling were analyzed and obtianed, which could provide information for potential risk recognition. Besides, standard value of Level 2 criterion 2nd chek were proposed, and several suggestions were put forward for the development of direct stability assesment.
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    Geometric Correction Method for Shell’s Stability of Ring-Stiffened Concave Cone-ToroidCylinder Combined Shel
    ZHANG Er, WU Fan, MAO Kairen, WU Chunfang
    2016, 50 (03):  431-436. 
    Abstract ( 745 )   Save
    Abstract: The ringstiffened concave conetoroidcylinder combined shell is a new joint structure. The shape of geometric imperfection and location of the joint was analyzed and the typical imperfection which had the greatest impact was calculated by using finite element simulation to study the method of correcting shell’s stability. Besides, the effect of structural parameters on geometric correction coefficient Cg was analyzed by conducting singlefactor numerical experiment. It is found that the Cg of cone which is next to the toroid has a different relationship with structural parameters compared with that of common cone. The method to calculate Cg is proved to be very precise, which justifies that it can be used in engineering calculation.
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    Simulation of Wave Breaking Based on NonHydrostatic Equations
    ZOU Guoliang, ZHANG Qinhe, ZHANG Na
    2016, 50 (03):  437-442. 
    Abstract ( 833 )   Save
    Abstract: A numerical model was developed for simulating wave propagation and breaking in nearshore zone with higher computational efficiency based on SWASH which is a on nonhydrostatic equations model to ensure essential numerical precision. In order to reduce vertical layers, nonhydrostatic equations were switched to nonlinear shallow water equations with hydrostatic approximation while a turbulence model was simultaneously introduced to describe the energy dissipation of breaking waves. The model was verified by experimental data of flume experiments such as wave breaking on a slope bottom, submerged breakwater and a sand bar. These validations show that the model is very effective in reasonably predcting wave breaking location and breaking wave height. This further illustruates that the nonhydrostatic model adopting realatively few vertical layers can be more attractive and competitive in actual engineering appliations.
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    Back Analysis of Permeability Parameters Under Unsteady Seepage of Seawall
    HUANG Ming, LU Yingshou, LAN Zhuguang, LIU Jun
    2016, 50 (03):  443-447. 
    Abstract ( 767 )   Save
    Abstract: Unsteady seepage of seawall was studied by using the finite element method in view of the effect of rapid fluctuation tidal. The back analysis objective function was constructed based on the finite element analysis results together with monitoring values. Then, the back analysis process of the permeability parameters of seawall was presented. The hierarchical searching technique was used in the back analysis. The small reasonable region of parameters was determined by the stepwise scanning method while the first order gradient optimization algorithm was used to confirm permeability parameters in the above region. The permeability parameters confirmed by back analysis were used in seawall unsteady seepage calculation. The instance shows that the calculation and back analysis process are reasonable and feasible, and the seepage pressure simulation results agree very well with monitoring sequences not only in numerical values but also in dynamic rules.
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    Prototype Monitoring Technique for Deep Water Floating Platform
    XIE Ribin, HUANG Dong
    2016, 50 (03):  448-455. 
    Abstract ( 904 )   Save
    bstract: In this paper, the prototype monitoring methodology and monitoring technology were discussed. Considering the special environmental conditions and floater motions in deep water, measurement information was proposed to represent comprehensive operating conditions of floating platform. A prototype monitoring system was designed, manufactured and applied to a semisubmersible platform in South China Sea. Analysis was conducted to prove the reliability and feasibility of proposed monitoring system.
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    Dynamic Response Analysis for Landing Collision of a New Underwater Lifting Device
    HU Yongli, YIN Hanjun, WANG Shengwei, YAO Baoheng, LIAN Lian
    2016, 50 (03):  456-459. 
    Abstract ( 874 )   Save
    Abstract: The dynamic equation for collision was established and solved by using the central difference method. Structural dynamic responses for landing collision of a new underwater lifting device supporting an operationtype ROV (Remote Operated Vehicle) were studied by using numerical simulation. The whole velocity, effective stress, elastic strain, plastic strain and the second collision in the collision course were analyzed. By comparing the simulation result of five common landing conditions, the influence of landing velocity on structural dynamic response was analyzed, providing a theoretical basis for structure design and load selection of underwater lifting device.
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    A Two-Dimensional Numerical Study of Vortex Induced Motion of a Semi-Submersible with Rectangular Sections in Coupling Currents and Waves
    WU Fan, XIAO Longfei, LIU Mingyue, TIAN Xinliang
    2016, 50 (03):  460-464. 
    Abstract ( 675 )   Save
    Abstract: A deep draft semisubmersible (DDS) in certain flow conditions is subjected to vortex induced motions (VIM), which significantly influences the loads and fatigue of moorings and risers. To investigate the VIM of a DDS with four rectangular columns in uniform current coupled with waves, a numerical study using CFD method was conducted. The current in a typical current of 135°was chosen by coupling with sinusoidal oscillatory flows used to simulate the waves with different KC numbers and relative current numbers were chosen. The results show that the VIM response of this kind of DDS with four rectangular columns in current with oscillatory flows is more significant than that in the current. The oscillatory flows have an important influence on the VIM response of the DDS.
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    Numerical Method to Predict Failure of Carcass Layer of Unbonded Flexible Risers
    REN Shaofei, TANG Wenyong, XUE Hongxiang
    2016, 50 (03):  465-471. 
    Abstract ( 756 )   Save
    Abstract: In order to investigate the failure property of carcass layer, the lay angle, initial ovality and material nonlinearity of carcass layer were considered in this paper. Meanwhile, three kinds of contact conditions, i.e, bonded coupling, coulomb friction with friction coefficient, and smooth friction were adopted to simulate the contact between adjacent surfaces of carcass layer. Finally, failure properties of a typical carcass layer of unbonded flexible riser under uniform external pressure and two forces acting along a diameter were predicted by using ABAQUS. It is shown that the contact condition between adjacent surfaces of carcass layer has a great influence on failure property. The lay angle effect on failure property can be ignored. With initial ovality and material nonlinearity, the critical pressure of carcass layer under uniform external pressure is sharply decreased, while the radial displacement of carcass layer under crushing is greatly increased. The numerical method can remedy the flaw of analytical method which cannot take the above factors into consideration.
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    Track-Keeping and Positioning Control in Vessel Towing Operation
    YU Shengjie, PANG Shikun, LI Yinghui, ZHANG Yufang
    2016, 50 (03):  472-478. 
    Abstract ( 855 )   Save
    Abstract: Considering the marine environment and cable drag force in vessel towing operation when trackkeeping and positioning, the motion model coupling between the vessel, the towed cable and the towed body was built. The control system had a strong nonlinearity and the design FuzzyPID (proportion integration differentiation) controller synthesis for the effect of fuzzy control alone was not satisfactory. The controller contained three modules, i.e., large error used Fuzzy control module, small error used FuzzyI control module, and microerror used FuzzyPID synthesis control module. The simulation result showed the track of towed body when the vessel was under disturbance, and verified the stronger antiinterference and robustness of the controller through point positioning control simulation. This algorithm is able to achieve high accuracy positioning control.
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    Relationship Between Dyslipidemia and Proteinuria in Patients with Diabetic Nephropathy
    LI Junhui, CHENG Dongsheng, WANG Feng, FEI Yang, XUE Qin, WANG Niansong
    2016, 50 (03):  478-482. 
    Abstract ( 765 )   Save
    Abstract: The relationship between 24 h urine protein excretion with dyslipidemia in diabetic nephropathy(DN) patients was evaluated. A total of 122 DN patients (49 females and 73 males) with an average age of (62.26±12.67) were included in this study. 24hour urine were collected for 24h protein(24 h pro) measurement and blood samples were taken as lipid parammeters. According to 24 h pro assays, subjects were divided into nephrotic group and nonnephrotic group. Lipid profiles and correlation analysis were compared between the two groups. It is found that the levels of total cholesterol(TC), non high density lipoprotein (NHDL), lipoprotein (a) [Lp(a)], and apolipoprotein B (ApoB) were much higher in nephrotic group compared with nonnephrotic one (P<0.05). In correlation analysis, TC, NHDL, ApoB and ApoE were found to be related to 24 h urine protein and HbA1C (P<0.01) respectively and Lpa was related to 24 h pro and eGFR. LDLC and TG were independently associated with HbA1C (P<0.01) while ApoA1 was only associated with 24 h pro (P<0.05). In each group classified according to quartiles of lipid profile, it is found that the proportion of patients with >3.5 g/24 h urine protein excretion grew progressively with the increase in TC, NHDLC, TG, ApoA1, ApoB,Lpa and ApoE (P<0.05) while LDLC and HDLC had no statistical differences (P>0.05). Conclusion: In patients with diabetic nephropathy, an obvious dyslipidemia was observed with increase of 24 h urine protein excretion, especially in those with nephrotic syndrome who mainly present with the an elevation in TC, NHDL, Lpa and ApoB. Since dyslipidemia could aggravate the progress of kidney disease, an effective control of lipid profile is likely to improve the prognosis.
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