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20 April 2008, Volume 27 Issue 2 Previous Issue    Next Issue

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Mechanic Analysis on Vertical Prestressing Bar to Continuous Rigid Framed Bridge CHEN Yan-ru, ZHOU Shui-xing, CHEN Zhan-rong 2008, 27(2): 173-176,184.  Abstract ( )   PDF (363KB) ( )   Vertical prestressing bars play a great role in controlling the principal tensile stress of webs. According to existing norms, the ratio of the vertical prestress loss to different length of the vertical prestressing bars is analyzed. In view of the current design of the delay tensioning vertical prestressing bar, the impacts to the continuous rigid-framed bridge by each of the three different delay tensioning methods is analysed, and the reasonable prestressing time is given based on the analysis. The reasons for the webs in a single vertical prestressing bars under the stress distribution and on the edges of web tensile stress are analyzed in detail, by establishing the detailed FEM simulation model of webs, and then the advice how to avoid stress on the edge of tectonic is given. Related Articles | Metrics

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Study on Stress Transfer in Steel-Concrete Joint of Hybrid Arch Bridge YAO Guo-wen, ZHOU Duan-ming, ZHOU Zhi-xiang 2008, 27(2): 177-180,220.  Abstract ( )   PDF (410KB) ( )   It is very important for the steel and concrete in the hybrid structures to integrate effectively and carry loading reliably. The safety and performance of steel-concrete hybrid arch bridge depend on the design of its pivotal steel-concrete hybrid joint. Stress distribution of three kinds of the steel-concrete hybrid joint is simulated in FEM. And the stress transfer rules are further probed in steel, hybrid joint and concrete. The results show that the high stress in steel box will be gradually and effectively transferred and dispersed into concrete box after increasing the number of ribbed stiffeners, the area of bearing plates and the end section of concrete box. In that case the stress concentration will be decreased greatly in the steel-concrete hybrid joint. Related Articles | Metrics

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“Two Stage Method” of Cable Tension Optimization for Short/Medium Span Cable-Stayed Bridges CHEN Zhan-rong, LIU Qi, ZHOU Shui-xing 2008, 27(2): 181-184.  Abstract ( )   PDF (271KB) ( )   Based on the theory of Influence Matrix, with the constraint optimization and the positive disposition analyses as its core, the "Two Stage Method" which is used for the cable tension optimization on short or medium span cable-stayed bridges is proposed. And then, an example is used to verify the correctness of this method. It can get the reasonable cable tensions without inverse analysis. This method can accelerate the solution procedure of cable tension optimization and it would be useful in the analysis of both the finished dead state and construction stage in short/medium span cable-stayed bridges. Related Articles | Metrics

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Improvement of the Least-Squares Fitting Method to Calculate Bridge Design Flow PENG Li-li, ZOU Yi-Song, CHE Jing 2008, 27(2): 185-187,212.  Abstract ( )   PDF (311KB) ( )   At present the bridge hydrology is mostly calculated in expeziential statistic. This calculating method makes use of Pearson Ⅲ curve as the theoretical frequency curve to draw appropriate lines. The method needs to compute many times to find the most suitable answer and has to draw theoretical frequency curve and experience frequency points. In order to avoid such shortcomings and improve the computational efficiency, the curve fitting method had been proposed. Hyperbolic functions as the basic functions for the least-squares fitting method are used to displace power functions, which is commonly used as basic functions to further improve the computational accuracy and efficiency. Related Articles | Metrics

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Structure Reliability Calculation Method Based on Finite Element-Artificial Neural Network-Monte-Carlo XU Yong-jiang, XING-Bing, WU Jin-liang 2008, 27(2): 188-190,216.  Abstract ( )   PDF (330KB) ( )   According to reliability theory,based on Finite Element, Artificial Neural Network and Monte-Carlo (F-A-M),a new structure calculation method is developed. First,finite element analysis model is built up,inputting values of the structural parameters and loading at random,and then response of the structure is recorded.The number of the record is limited,but it is enough to train the Artificial Neural Network (ANN). After ANN being trained with the training samples,a highly nonlinear mapping relationship between the efficacy and response of the structure is gained. Making use of the generalization capability of ANN,sufficient structural response value is developed at random. Then the reliability of the structure is calculated by the Monte-Carlo method. This approach which not only makes full use of the merit of ANN and Monte-Carlo,also makes the calculation more effective, provides a fresh method for the reliability of structure. Related Articles | Metrics

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Analysis on Limitation of Current Standard about Bridge Aerodynamic Admittance Theory ZHUGE Ping, LU Peng-zhen 2008, 27(2): 191-194.  Abstract ( )   PDF (320KB) ( )   Aiming directly at the limitations of aerodynamic admittance function of current sdandard, and in order to describe the effects of aerodynamic admittance function to buffeting, various factors that affect the aerodynamic admittance are put forward by overall theoretical analysis. The limitations of current aerodynamic admittance function are tested by programming and wind tunnel test. Then it is pointed out sequentially that a systematic aerodynamic admittance theory is necessary. The results provide theoretic bases for better assurance of the buffeting theory and the project applications. Related Articles | Metrics

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Theory and Application of Construction Mechanics to Big-span Bridge LUO Ling, CAO Shu-shang, KUANG Jian 2008, 27(2): 195-199.  Abstract ( )   PDF (369KB) ( )   Construction mechanics which mainly studies behaviour and characters in construction stage is a development on the basis of engineering mechanics. The formation of bridge construction mechanics theroy promotes the development of construction techniques and becomes the basis of construction control techniques in big-span bridges. Bridge construction mechanics theory has many achievements, such as calculation method of superposition of beam dead load endogenous force, calculation method of superposition of deflection, calculation method of creep and effective prestressing force and most dangerous state and temperature influence in construction and thermal stress of cement concrete at an early stage, determination of construction order and methods,and so on. A big-span continuous rigid frame bridge is taken as an example which shows the application of construction mechanics. Related Articles | Metrics

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Study on Internal Force Distribution Method of Co-Section for Arch Bridges Strengthening HUANG Hai-dong, XIANG Zhong-fu, LIU Jian-feng, LIN Xiao-feng 2008, 27(2): 200-203,247.  Abstract ( )   PDF (344KB) ( )   It's common to strengthen arch bridges by enlarging section, and the combined section belongs to the "Two-Stage Loading Composite Structure" in mechanics of characteristics. The internal force distribution method of co-section is ratiocinated on the base of assumption of the plane section, and is used in the design of arch bridges strengthening. It can be reference for the same kind of bridges in calculation and strengthening design. Related Articles | Metrics

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Study on Duplicate Arch Bridge Reinforcement and Protection GUO Rui-dong, ZENG De-rong, LI Jie 2008, 27(2): 204-207.  Abstract ( )   PDF (291KB) ( )   Taking the process of the reinforcement and protection of a duplicate arch bridge as an example, it is super-posited by Guojiaolong old arch bridge in Shizhu in Chongqing and one modern arch bridge. Common damages and causes are found through investigating and computer model discussion. The reasons of protection are analyzed and methods of bridge reinforcement are provided. Related Articles | Metrics

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Model's Establishment and Analysis of Engineering Life Cycle Cost for Bridge Rebuilding Project BAI Hong-tao, WANG Fu-min 2008, 27(2): 208-212.  Abstract ( )   PDF (396KB) ( )   Making use of some basic principles of technique economics, on the base of the funds' time value, every possible cost of the reinforcement and the reconstruction for the highway and bridge which happened during the life cycle has been analyzed through comparing with others; what's more, a comparative scheme model has been made, too. At last, an example is given to show the process of comparing schemes, which aims to give some references to select a reasonable reconstruction scheme for the current highway and bridge. Related Articles | Metrics

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On Bridge and City View CHEN Zheng-bin 2008, 27(2): 213-216.  Abstract ( )   PDF (362KB) ( )   By focusing on the problems in the design of bridge appearance, the relationship between bridges and city view is analyzed, and the idea that visual aesthetic value of bridge should be taken into consideration when an urban bridge is designed has been put forward. Related Articles | Metrics

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Discussion on Vehicle Flow Density Factor in Tunnel Ventilation Design HAN Xing, ZHANG Xiao, ZHANG Xu 2008, 27(2): 217-220.  Abstract ( )   PDF (275KB) ( )   The vehicle flow density factor in Specifications for Design of Ventilation and Lighting of Highway Tunnel was discussed, and the formula expressions of vehicle traveling distance in tunnel were deduced to conclude that the tunnel ventilation flow rate is not related to the vehicle flow density under certain traffic flow rate. Afterwards, the relationship between vehicle speed and traffic flow rate was discussed, which led to the point that the vehicle flow density factor is the amendment of traffic flow rate actually and its value should be reconsidered on the base of certain traffic flow theory. Related Articles | Metrics

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Application of Origin Software to Analyzing Deformation Monitoring Data during the Construction of Tunnel CHANG Bin-bin, LIU Shan-hong, HAN Jian 2008, 27(2): 221-224.  Abstract ( )   PDF (353KB) ( )   The fundamental function and application of Origin software are introduced. Plotting and non-linear curve fitting measured date can be finished by Origin software. At the same time, reliable parameters and visualized figures can be obtained. An example is taken to analyze procedure of monitoring and measurement data of Shi-long-shan tunnel. The analyzed results have been used to guide the design and construction of excavating and shoring the structure of tunnel. Related Articles | Metrics

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Optimal Analysis on Entrance Construction Scheme for Changchong Tunnel FAN Xiao-wei, XU Lin-sheng 2008, 27(2): 225-227,289.  Abstract ( )   PDF (299KB) ( )   Based on engineering geological feature of tunnel setting, a finite element of entrance of Changchong tunnel is established, which can simulate the construction process under the bench method and CD method. Displacement, stress, characteristics of yield degree of surrounding rock and the force of supports structure are analyzed. Construction process and stress of these two methods are compared so as to optimize the practical construction scheme. The result indicates that bench method is better than CD method. Related Articles | Metrics

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Coupling Mechanism Analysis on Cavern Tunnel Disease Forming LI Ming, CHEN Hong-kai, YE Si-qiao 2008, 27(2): 228-231.  Abstract ( )   PDF (318KB) ( )   Cavern tunnel diseases, mostly forming underground stress field under the action of damage,seepage,temperature and other factors, are very complicated nonlinear coupling process. Using the stimulate-response coupling system made up of Bui damage model and seepage field, the result shows that the diseases will be formed obviously when the coupling strength factor is about 0.5, with the cranny expanding and the damage increasing in the surrounding rock; the plastic radius of underground rock is increasing with the porous hydraulic pressure; it speeds tunnel diseases to come into being; it has some positive significance with guidance to prove up the coupling mechanism, the repair and the protection of the cavern tunnel. Related Articles | Metrics

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Research on Inertial Point Method by Using FEM YANG En-hui, QIU Yan-jun, JIANG Xin 2008, 27(2): 232-235,267.  Abstract ( )   PDF (367KB) ( )   The responses of asphalt pavement to static and dynamic FWD load are analyzed by using the finite element program ABAQUS, to try to find the inertial point in the surface deflection basin. The results illustrate that there are significant differences between the dynamic response and the static response, comparing with the result of static linear elastic theory. There may be obvious errors at the result of backcalculation if the dynamic effects and the sub-base are not considered in backcalculation. The precision of backcalculation can't satisfy the engineering requirement. Related Articles | Metrics

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Analysis on Viscoelasticity of Asphalt Mixtures Using Pseudo Strain ZHAO Yan-qing, HUANG Da-xi, PAN You-qiang 2008, 27(2): 236-239.  Abstract ( )   PDF (262KB) ( )   As a typical viscoelastic material, asphalt mixtures behave in a complex way. The concept of pseudo strain can be utilized to simplify the analysis. Complex modulus tests were conducted under various conditions for a superpave13 mixture, and the test results were converted to Prony series of relaxation modulus. Havesine loading tests and constant crosshead tests were performed for the mixture and pseudo strains were calculated on the base of the relaxation modulus. Viscoelastic constitutive relationships were studied, and the results show that hysteretic effects and influences of loading time or loading rate on viscoelastic materials can be removed by using pseudo strain. There is a linear relationship between stress and pseudo strain, thus extended elastic-viscoelastic correspondence principle can be used to analyze the behavior of asphalt mixtures. Related Articles | Metrics

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Research on Tenacity Experiment and Enchanced Toughness Mechanism of Polypropylene Fiber Concrete as Road Surface HE Zhao-yi, ZHANG Zheng-guo, WANG Guo-wei 2008, 27(2): 240-243,282.  Abstract ( )   PDF (360KB) ( )   According to the ASTM C 1018 resilience index method, choosing the pole value to be the characteristic point experiments on the polypropylene plastic steel fiber concrete are made. Through tenacity results of the polypropylene fiber concrete, conclusions that the best usage of the polypropylene fiber is 4 kg/m3 and the low strength concrete increases the tenacity better than the high strength concrete does are obtained. The tenacity mechanism of the polypropylene fiber concrete are discussed theoretically. Related Articles | Metrics

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Research on Moisture Susceptibility Evaluation of Fiber Asphalt Mixture ZHANG Yuan-hang, WU Guo-xiong, MENG Qiao-juan 2008, 27(2): 244-247.  Abstract ( )   PDF (310KB) ( )   Through testing moisture susceptibility of fiber asphalt mixture by Marshall immersion test and freezing-thawing cyclic indirect tensile test, the conclusion that the two methods can not evaluate moisture susceptibility of fiber asphalt mixture effectively is drawn. Vauum saturated freezeing-thawing cycle dispersion test was used to evaluate moisture susceptibility of fiber asphalt mixture comprehensively by flying shards losses and the loss rate. The test results show that this method and evaluation indicators can simulate actual conditions of the road better, and more effectively evaluate moisture susceptibility of asphalt mixture. Related Articles | Metrics

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Application of AHP-Fuzzy Method to Evaluating Locating Asphalt Concrete Batch Station ZHOU Fu-sheng, XIAO Sheng-xie 2008, 27(2): 248-251.  Abstract ( )   PDF (292KB) ( )   Based on a synthetical study on the influence factors of locating asphalt concrete batch station, the fuzzy evaluation method of locating asphalt concrete batch station is put forward. First, select 7 judgement indexes, and establish a numerical method of them. Then, adopt AHP method to define the weight coefficients of each indexes. Then, a fuzzy evaluation model is set up. Finally, the engineering example is analyzed by the method. As a result the feasibility and effectiveness of AHP-Fuzzy evaluation method of locating asphalt concrete batch station are proved. Related Articles | Metrics

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Study on Proportion Design Method of High Performance Concrete WANG Rui-yan, TIAN Wen-yu, XIONG Chu-hua 2008, 27(2): 252-254.  Abstract ( )   PDF (216KB) ( )   Combining with the application study of high performance concrete used in the construction of Chongqing ShiBanpo Changjiang bridge, the multiple linear relationship between concrete's strength, cenment ratio, cement strength and cement-water ratio has been obtained. The conclusion can provide the basis for proportion design of high performance concrete. Related Articles | Metrics

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Discussion on Vertical Bearing Capacity of Rock-socketed Pile ZHAO Shi-hang, XU Xi-bin 2008, 27(2): 255-258.  Abstract ( )   PDF (290KB) ( )   According to the method of the rock-socketed pile vertical bearing capacity in the norms, existing problems and unreasonable place are analyzed. The gray system theory of forecasting the vertical bearing capacity of rock-socketed pile is put forward. With the grey theory,the GM (1,1) model was established in the project of pile foundation. The testing result gears with forecasting result very well under the precise check. A theoretic method of forecasting the capacity in pile foundation is provided. Related Articles | Metrics

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Rankine-Type Solutions for Passive Earth Pressure in Saturated Backfill WANG Jun-jie, CHAI He-jun 2008, 27(2): 259-263,275.  Abstract ( )   PDF (376KB) ( )   Some theoretical solutions for Rankine's passive earth pressure acting on retaining walls by saturated soil mass with/without steady water seepage are developed. Without load acting on the surface of the backfill, the wall is only acted by passive earth pressure in the case with steady water seepage; it is acted by both earth and water pressures in the case without water seepage. In the solution of the passive earth pressure in the case with water seepage, the saturated soil unit weight is used; but in the case without water seepage, the buoyant soil unit weight is used. With uniform load acting on the surface of the backfill, in the case with the water seepage through the backfill, the wall which is provided with a drainage system along the soil-structure interface is only acted by passive earth pressure except for the instant applying the load. And in the case with the water seepage and a drainage system along the backfill base, after the excess pore water pressure in duced by the uniform load dissipated completely, the wall is only acted by passive earth pressure; before the excess pore water pressure is dissipated, the wall is acted by both earth and water pressures, but the magnitude and distribution of the earth and water pressures change with changing the degree of consolidation of the soil mass under the uniform load. And in the case without water seepage, the wall is also acted by both earth and water pressures. Related Articles | Metrics

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Strategies for Prevention and Treatment of Water Injury to Riverside Highway WANG Qing-zhen, LI Tian-sheng, Gan Lin-kun 2008, 27(2): 264-267.  Abstract ( )   PDF (346KB) ( )   The water injury is one of most principal natural calamities on highway. Due to the characteristics of widely dispersing, frequently occurring and enormous harm, the water injury not only seriously affects the operation and safety of traffic and transportation, but also causes great losses in economy. By analysis on some common forms of water injury, several strategies for prevention and treatment are proposed. Related Articles | Metrics

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Territory Debris Flow Disaster Formation Mechanism and Developing Trends after Construction of Three Gorges Project in Chongqing ZUO Ke, ZHANG Qi, CAO Wen, LI Feng, ZHANG Ying 2008, 27(2): 268-271.  Abstract ( )   PDF (354KB) ( )   Based on systematic analysis on the territory of Chongqing debris flow geological development of the macro-environment,it is probable to occur large and extra large debris flow disaster in Chongqing. According to absorbent soil in tensity attenuation law and indoor physical model testing, right slope mudslides and valley debris flow formation mechanism are studied. And the systematic study of the situation in Chongqing debris flow velocity formula provides the prevention a scientific basis. With the utilization of expert system approach, the situation of Chongqing debris flow developing trends is outlined, which provides a scientific basis for the comprehensive utilization of territory of land and resources. Related Articles | Metrics

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Analysis on Infection of Station Excursion for Monitoring Result YUE Ren-bin, XIONG Xian-cai, LEI Xiao-hua, ZHAO Jian-yun, CHEN Wei-min 2008, 27(2): 272-275.  Abstract ( )   PDF (278KB) ( )   Using total station for real-time monitoring on large structures,which is confined to building structures, landform or other impersonal factors, sometimes the survey station has to be set in the deformation area. In the course of the real-time monitoring, when the station in the deformation area has an excursion,but the occupying data still keep original ones, thus the monitor data will contain large errors. To resolve the problem, a formula has been proposed to eliminate the error. And simulation experiment has been conducted. The results of this experiment show that the method can eliminate the error from station excursion completely and it is easy to be put into practice. Related Articles | Metrics

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Study on the Reasonable Spacing of Highway Intersections ZHANG Lan-fang, FANG Shou-en 2008, 27(2): 276-278,285.  Abstract ( )   PDF (308KB) ( )   Highway intersections are studied in depth,and key influences factors are suggested. The functional intersection area and steady movement area of highway intersection are analyzed by theories and experiments. The method of simulation is adopted to analyze delay, traffic volume, signal period at intersection. The reasonable spacing of highway signal intersections and no signal intersections are put forward. Related Articles | Metrics

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Application of Artificial Counting Method to Investigating Traffic Flow of City Regional Road Network HUANG Hua-hua, ZHANG Xue-jin 2008, 27(2): 279-282.  Abstract ( )   PDF (253KB) ( )   The application of artificial counting method to getting the volume of traffic of the regional road network is in droduced. Through analyzing the data of the regional road network of Lianglu Kou areas of Chongqing, the traffic flow characteristics of LiangLu Kou areas are grasped. The experiment proves the feasibility of this method. Related Articles | Metrics

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Reconstruction and Extending Model of City Trunk Roads Network Based on Equilibrium Theory LIU Yi-zhou, JIAO Hai-xian, HU Ying-peng 2008, 27(2): 283-285.  Abstract ( )   PDF (225KB) ( )   Some hypothesized nodes and hypothesized roads network were established, which depended on the land function, traffic blocking area and trunk roads network of the city. Adopting technology of OD iterative procedure, the OD trips of hypothesized network were obtained. Then the equilibrium theory was used to assign the OD trips and to get systemic and structural parameters of this network. Finally, the optimum extending strategy of city trunk roads network was proposed by analyzing those parameters, promoting the integration of the city roads network. Related Articles | Metrics

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Forecast Method about the Traffic Impact of Large Scale Building putting on Transport Network Based on BP Network REN Qi-liang, LI Shu-qing 2008, 27(2): 286-289.  Abstract ( )   PDF (321KB) ( )   The traffic impact analysis of large-scale building is more and more emphasized by the transportation engineering experts, the city planning and managements. How to predict the impact on the surrounding road network is the core problem in traffic impact analysis. Three-layer BP network predict model on traffic impact is built up according to the basic theory of artificial netural network, and the feasibility of the method is proved by taking Chongqing Nan'An sports center as an exemple. Related Articles | Metrics

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Two-Dimensional Mathematical Model of Regulation of Tonggutan Reach in the Yangtze River ZHAO Zhi-zhou, ZHOU Hua-jun, YANG Sheng-fa 2008, 27(2): 290-292.  Abstract ( )   PDF (217KB) ( )   Based on the analysis of basic characteristics of Tonggutan Reach in the Yangtze River, variations of the navigable conditions caused by the regulation project are investigated by 2-D mathematical model.The results show that the navigable conditions in the reach after implementation of the regulation project can basically meet the standards, but the branch will be with low stability. Related Articles | Metrics

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Experimental Study on the Fix Bed Resistance of Gravel River with High Gradient YANG Sheng-fa, HU Jiang, WANG Xing-kui 2008, 27(2): 293-297.  Abstract ( )   PDF (341KB) ( )   Based on the velocity distribution experiment and from coarse material incipient motion experiment in 1-m flume, the law of the fix bed resistance is found in the high gradient bed. First, the law of the fix bed resistance agrees with the Chey-Manningformula. The Darcycoefficient in this studyis close tothe formula of Colebrook (1938). Next, velocity distribution obeys logarithm law when h/Ks>2. Finally, it has been found that results of the two experiments are close although their methods are different in the high gradient bed. Related Articles | Metrics

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Analysis on Structural Property in Container Terminal Bridge Crane Through Finite Element Method TIAN Jian-zhu, WANG Duo-yin, ZHOU Shi-liang 2008, 27(2): 298-301.  Abstract ( )   PDF (378KB) ( )   Finite Element Method is an effective method in structural analysis. The procedure of Finite Element Method in analysis of container terminal is introduced, and the error analysis is explained. The model made up of shell element, tetrahedron element and invirable section beam element is built up to analyze every working condition. Based on that critical condition, the critical stress and the critical deformation are got, and the result proves to be right. Related Articles | Metrics

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Container Throughput Forecasting Based on Gray Method and Exponential Smoothing Method SHI Ze-jun, LI Kai 2008, 27(2): 302-304,332.  Abstract ( )   PDF (294KB) ( )   A composite prediction method is put forward based on gray method and Three-exponential Smoothing method. Container terminal input/output system is a gray system, so the Gray GM (1,1) method is chosen to forecast the throughput of Ningbo port. Three-exponential Smoothing method is used to forecast the throughput of Ningbo port for the curve of throughput is keeping rising during these years. Based on the two methods, composite prediction technology is used to forecast the container throughput of Ningbo port. Related Articles | Metrics

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Hydrochemistry Types of Surface Water and Groundwater in Huaisha River Basin and Groundwater Resources Protection LIU Xiang-chao, SONG Xian-fang, XIA Jun, YU Jing-jie, YANG Cong 2008, 27(2): 305-309.  Abstract ( )   PDF (436KB) ( )   The Huaisha River basin located in Huairou district of Beijing City is surveyed, and the spring water, river water and well water in the basin are tested; and then the hydrochemistry components of the samples are analyzed, at last the spatial distribution disciplinarian and evolvement tendency of the hydrochemistry of the water bodies are illuminated. Thus scientific foundation is offered not only to realize regional surface water and groundwater resources protection, but also to water resources sustainable exploitation, utilization and management. Related Articles | Metrics

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Application of Electric Controlling and Engine Driving 4W S to Modern Car ZHANG Hui-ping, YANG Zhi-gang 2008, 27(2): 310-312,316.  Abstract ( )   PDF (310KB) ( )   The basic structure and operating principle of electric controlling and engine driving four-wheel steering (4W S) system are introduced. The technique for choosing well electric engines for steering and driving respectively, and choosing sensors are also displayed. Based on the study on current electric control technique and equipment, the developing tendency of improving the electric control technique for 4W S in the future is suggested. Related Articles | Metrics

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Method for Subdividing Highway Freight Market with Analytical Hierarchy Process and Gray Relative Analysis TANG Qiu-sheng, ZHANG Yang, LI Ping 2008, 27(2): 313-316.  Abstract ( )   PDF (299KB) ( )   The algorithm of segmenting the highway freight market was put forward with analytical hierarchy process and gray relative analysis, and its rationality was confirmed by a case. It provides a basis for highway freight of enterprises to make scientific decisions and conduct target marketing. At last, corresponding marketing strategy is proposed in view of different subdivision of the market. Related Articles | Metrics

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A Facile and Simple Approach to 6-Bromo-1,1'-bi-2-naphthol YUAN Xiao-ya 2008, 27(2): 317-319.  Abstract ( )   PDF (239KB) ( )   Enantiopure (R) or (S) 6-Bromo-1,1'-bi-2-naphthol was prepared with high enantioselectivity (>99% ee) through selective mono-bromonation during an introduction and succedent remove of strong electron-drawing group starting from (R) or (S)-1,1'-bi-2-naphthol in three steps. This method described here was simple and operation-easy. Related Articles | Metrics

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Cooperation Mechanism of Two-stage Supply Chain with Asymmetric Information HOU Cai-xia, HONG Wei 2008, 27(2): 320-323,326.  Abstract ( )   PDF (408KB) ( )   A two-stage supply chain system consisting of a single supplier and several retailers is investigated. First, an in centive mechanism model that consists of a single supplier and several retailers is proposed with symmetric demand in formation and symmetric store fee information corresponding with a supply chain. Based on such a symmetric information model, another incentive mechanism model with asymmetric demand and store fee information is proposed, in order to cooperate the supplier and retailers. And also a firm cooperation mechanism for a long time between them is built up. It realizes the global optimization in an asymmetric information environment. Related Articles | Metrics

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Application of Grey Relational Analysis to Comprehensive Strength Appraisement of Each Bidder in Bid Evaluation WANG Hao, ZHANG Xiao-ting 2008, 27(2): 324-326.  Abstract ( )   PDF (214KB) ( )   According to Gray System Theory and Grey Relational Analysis, the Gray-target decision matrix is built based on evaluative factors such as launching cost, falling back rate of compacts. It may help the owner to appraise the comprehensive strength of each bidder and optimum seeking. This method improves the accuracy and objectivity of the decision-making and avoids one-sidedness of choice comparing with traditional means. Related Articles | Metrics

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Local Adjustment Algorithm for Constructing Constrained Delaunay Triangulation Based on Binary Sort Tree XIONG Bin, PU Hao, SONG Zhan-feng 2008, 27(2): 327-332.  Abstract ( )   PDF (460KB) ( )   Local adjusting is needed in two-step constructing constrained Delaunay Triangulation when inserting con-strained segments into existing Delaunay triangulation. Some investigations on that process are made and a algorithm is proposed on binary sort tree which is using for reconstructing impacted areas. With this algorithm, the impacted area can be spitted easily by generating a binary sort tree with indexes of the points stored in a segments array, and after reconstructing the topological relationship of triangles according to the relationship of binary tree nodes, the adjustment is completed. Recursive logic makes the algorithm brief and effective. Related Articles | Metrics

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Extension of Kantorovich Inequality on Spectval Norm with Its Application in Statistics DONG Zhi-qing 2008, 27(2): 333-334.  Abstract ( )   PDF (116KB) ( )   About Generalized Kantorovich Inequality, selecting proper norm of matrix formulation and its upper limit applies to estimating parameter of relative efficiency of linear model. By spectval norm, the upper limit of Generalized Kantorovich Inequality is ameliorated and then applies it to the relative efficiency of least squared estimator of linear model. Related Articles | Metrics