2003 Vol. 3, No. 4

Display Method:
Influence of asphalt poperties on porous asphalt mixture performance
NI Fu-jian, XU Hao, LENG Zhen, LIU Qing-quan
Abstract: Three kinds of porous asphalt mixtures with different bitumen but same air voids were tested, the performance of asphalt mixture AC-16-Ⅰ was analyzed. It is pointed that with the increasing of 60℃ viscosity, bitumen porous asphalt mixture's performances such as compressive strength, cleavage strength, tensile strength, dynamic stability, hydraulic stability and low-temperature anti-crack ability are markedly improved, but 60℃ viscosity has less influence on permeability and anti-skid ability, the strength performances of porous asphalt are inferior to density graded asphalt mixture. The results indicate that the 60℃ viscosity of bitumen is the key index that influences the performances of porous asphalt mixture and rather than conventional asphalt, the high viscosity modified asphalt could be adopted for porous asphalt mixture.More>
2003, 3(4): 1-4.
Reuse of scrap concrete slab in highway reconstruction
ZHANG Chao
Abstract: When reconstructing road on old line, the reuse of waste concrete has a great meaning for environment and construction cost. The physical and mechanical parameters of regenerated concrete that is based on waste concrete were measured. The parameters can reach the demand of standards. The testing road operation shows that the regenerated concrete can be used as semi-rigid base materials. Compared with common concrete, the anti-wear feature of regenerated concrete is not good enough, its other parameters have no difference.More>
2003, 3(4): 5-9.
Part hydroplaning effect on pavement friction coefficient
JI Tian-jian, HUANG Xiao-ming, LIU Qing-quan
Abstract: When vehicles run on the road that covered by water film, the pressure on vehicles'tire by water will occure, the pavement friction coefficient will be reduced. The dynamic pressure was analyzed with energy conservation theory, the relationships of the friction coefficient with the water film depth and the running speed of wehicle were calculated with finite element analysis. The results indicated that if vehicle's speed is low, the depth of water film is the larger influence fac-tor, if speed is high, the speed value is the larger influence factor.More>
2003, 3(4): 10-12.
Mechanical properties experiment of compacted loess-lime
ZHANG Hong-liang, HU Zhang-shun, LIU Bao-jian, WANG Jian-hai
Abstract: Based on the triaxial test of compacted loess-lime, whose rate of lime weighs to soil is 10%, compactness is 95%, the paper measured the stress and strain relationship curve, volume change curve and lateral change curve of the compacted loess-lime under different surrounding pressure, got the parameters of compacted loess-lime, such as elastic modulus, initiative volume modulus, initiative poission's ratio, peak strength, peak strain, residual strength, etc. Analysis results indicate Duncan-change model does not adopt to the compacted loess-lime, the modified Saenz formula can be used as the constitution equation very well.More>
2003, 3(4): 13-16.
Numerical analysis of reinforcement for unstable retaining wall
ZHANG You-pa, GAO Yong-tao, WU Shun-chuan, FANG Zu-lie
Abstract: According to the situations and the reasons of instability, the spray concrete with steel bar nets, preforced cables and cement grouting with high-pressure were adopted in the reinforcement design. Soil slope was also reinforced by mini-anti-sliding piles and cement grouting with middle-high pressure. A numerical calculation model was developed to analyze design parameters and materials properties. Using the model, the stability variations(displacement of side direction) of reinforcement structures and retaining wall, highway subgrade, soil slope as well as the axial force on the perforced cables and anti-sliding piles were analyzed. The analysis result shows the different types of reinforcement structure are integrated and formulated an organic entirety, and it is a very effective method to reinforce the unstable retaining wall.More>
2003, 3(4): 17-21.
In-suit monitoring for cables' tension with optical fiber grating sensors
ZHANG Xu-she, DU Yan-liang, JIN Xiu-mei, SUN Bao-chen
Abstract: The monitoring of cables' tension is very important for cable bridge safe operation with optical fiber grating sensors. The monitoring system was developed. In this system, the optical fiber was con-nected with sensers that were fixed on cables. The wave length of fiber varied with cables tension change, so the cables tension can be monitored by surveying fiber's wave length. The testing results show that this system has good performance and linear response capacity.More>
2003, 3(4): 22-24.
Disposing methods of airport asphalt pavement rolling compaction machines
SHI Bao-hua, CAI Liang-cai, SUN Tao, HUANG Bi-bin, LIANG Kai-jun
Abstract: Taking into account of such factors as the output of asphalt mix machines, production efficiency and paving depth of pavers and weather conditions, this paper analyzed the perform-ances of common rolling compaction machines and features of asphalt pavement construction to determine the types and model of machines. After a systematic experiment on the factors affect-ing the rolling compaction machine configuration such as the rolling compaction operation section length, the relation between rolling speed and compaction degree, roller grader effective working time coefficient, the paper put forward the method to calculate rollers' production rate and the method and formula of rationally disposing rolling compaction machines. The applied result proves this methods are effective.More>
2003, 3(4): 25-29, 34.
Dynamic modeling and simulation of three-piece bogie freieht car
WANG Yong, ZENG Jing, LV Ke-wei
Abstract: The modules and functions of ADAMS and ADAMS/Rail dynamic simulation software were introduced. A nonlinear mathematical model for the three-piece bogie freight car was established, in which a kind of contact model was adopted directly to build the model of the friction wedge inherent in the second suspension of the bogie. The vehicle system dynamic behaviors including hunting stability, dynamic curving behavior and ride index were analyzed by using ADAMS/Rail software. It is pointed that the modified three-piece bogie freight car can obtain more satisfied dynamic behavior by adopting several new technologies. The results indicate that more detailed and complicated vehicle models can be built using ADAMS/Rail, the simulation results are reasonable.More>
2003, 3(4): 30-34.
Temperature control method for jacket cooling water system of main marine diesel engine
WU Gui-tao, YIN Zi-bin, SUN Pei-ting
Abstract: Based on heat transfer theory, the paper analyzed the heat transfer mechanism of jacket cooling water system of main marine diesel engine, and put forward a dynamic mathematic model for the system. Since the system is great, it is difficult to control the cooling water temperature dynamic deviation. The paper studied an enhanced control method in order to decrease temperature dynamic deviation, the output power of main marine diesel engine was introduced as a feed forward signal. The results of computer simulation indicate that this control method has better control performance than current PID control.More>
2003, 3(4): 35-38.
Nonlinear control of underactuated ships
LI Tie-shan, YANG Yan-sheng, ZHENG Yun-feng
Abstract: The underactuated system and its meaning were introduced. The automatic berthing control model and straight-line tracking control model for underactuated surface vessels were de-veloped. A state feedback controller that forces an underactuated ship to asymptolically track a straight-line was presented using the input-output linearization technique. This controller was ap-plied to an example, its control was simulated with Matlab software. The results show that this control strategy can resolve the control problems of underactuated ships.More>
2003, 3(4): 39-43.
Fault diagnosis of diesel engine based on neural network
WANG Yun-song, CHU Fu-lei, LIU Ya-dong
Abstract: Based on virtual instrument technology, the fault diagnosis system for diesel engine was developed. Its digital treatment system was consisted of sensors and PCI-6023E collectors, its design software was LABVIEW6. 0. This system character parameters were defined by engine's typical faults. In this system, the collected data were treated with BP neural network to diagnose engine's faults. The tested results show that this system is feasiable.More>
2003, 3(4): 44-47.
Heat release rules of LPG/diesel mixing fuel engine
QI Dong-hui, BIAN Yao-zhang, WANG Heng, MA Zhi-yi
Abstract: The paper studied the influences of load, speed, mixing ratio, injection advanced angle and injection pressure on the rules of combustion pressure, heat release, ignition characteristics, etc. The results indicate that the ignition delay period of mixing fuel is obviously longer than that of diesel, the higher the mixing ratio is, the longer the ignition delay time is. When the mixing ratio is smaller, the maximum combustion pressure and the maximum pressure increasing rate of mixing fuel engine are as same as that of diesel, but when it is bigger, they are not so same as that of diesel. With the increase of mixing ratio, the maximum value of heat releasing rate increa-ses, and the crank angle delays. Injection advanced angle and injection pressure have influence on the combustion process.More>
2003, 3(4): 48-52.
Rapeseed oil as base oil of gasoline engine lubrication oil
LI Ying-bo, QIU Chao, WANG Yu-min
Abstract: The biodegradable engine oil must have a good lubrication mechanism and biodegradable performance. Rapeseed oil, which has a good biodegradable performance, was chosen as base oil, some additives were input to present an optimum formulation for 10W/40SG gosoline oil. According to uniform design method, a lot of experiments for comparing its antioxidizing and biodegradable performance to commercial oil were carried out. The results show that its quality can reach the standard demand, and its biodegradable performance is better than pretolatum-based engine engine oil.More>
2003, 3(4): 53-57.
Urban rail transit and railway terminal layout
YE Jun-qing, HE Xun-long
Abstract: Using system analysis and integrated induction methods, this paper analyzed how to plan passenger stations, goods stations and connecting railways in a railway terminal. The results show that the position and attraction radius of passenger station satisfy "1 h effect", goods station can set dispatch position at urban rail transit depot when it is moved out, urban rail transit can also work for freight conveyance, the big urban railway terminal always forms ringed or mixed mode.More>
2003, 3(4): 58-62.
Coordinate design method of urban roads and environment
XUE Kun, BAI Yu, YANG Xiao-guang
Abstract: The coordinate design idea and regulation were introduced, the design method was ana-lyzed. It is pointed out that this design method can effectively improve Chinese urban traffic and environment. When building a new main line, the land along the road should be preserved enough, while the traffic volume increasing in future, the road can be widened, but the landscape will not be destroyed. When reconstructing an old line, the installations along the road, which have bad influence on landscape and environment, should be removed.More>
2003, 3(4): 63-67.
Optimal model of urban bus frequency determination
NIU Xue-qin, CHEN Qian, WANG Wei
Abstract: The scientific determination of bus frequency is very important for public traffic efficiency. According to bus dispatching mode in Chinese city, an optimal model for bus frequency determination was developed. In this model, the maxization of passengers satisfaction and bus company efficiency was objective function. The algorithm of this model was presented. An example shows that this model is feasible.More>
2003, 3(4): 68-72.
Simulation of beer game in logistics with Matlab
LIU Xiao-feng, ZONG Bei-hua
Abstract: A beer game model was developed with Matlab/Simulink software, it was simulated with computer. Through this model, the influence of order delay on logistic system inventory was analyzed, the effect of different procurement plans on beer game was researched. It is pointed out that the order delay is the main reason for bullwhip effect in beer game, if sellers pay too much attention to the inventory, the bullwhip effect will be aggravated, and the logistic cost will be in-creased. The results show that the Matlab/Simulink simulation technique is efficient for analyzing logistic system.More>
2003, 3(4): 73-77.
Application of artificial neural network in airline customer segmentation
ZHOU Hong, XU Li
Abstract: The segmentation of airlines passengers based on mileage can not reflect passengers characteristics. The model that can show passengers value was developed. In this model an artificial neural network was applied to give a topological maps, with the maps, the data that can indicate passengers value was collected. An example proves that the accuracy to seperate passengers by their value with this model is 90. 8%.More>
2003, 3(4): 78-81.
Decision support system of railway passenger-goods marketing
CHEN De-liang, LEI Ding-you
Abstract: The system was developed with data warehouse technique. Its logic structure, Information characteristics, data source organization and data mining were analyzed. The key techniques to realize the system was presented. It is pointed out that the unity strategy of data and database model are the most important works.More>
2003, 3(4): 82-84.
Different discriminate price strategy in transportation enterprise
FANG Xiao-ping
Abstract: This paper used microeconomics method to analyze carrier's behavior in different structural market of transportation. The phenomenon that the imperfect competitor and monopolist usually make use of market power to maximize its benefits expresses that a firm's market power is decided by the demand flexibility and the number of substitutes. Imperfect competitor can make use of different discriminate price strategy based on special circs to maximize its benefits. Railway enterprises, which need a great of fix cost, but comparatively small part of variable cost, also can seek optimum price combination by using discriminate price strategy. If a railway enterprise want to make use of discriminate price strategy rationally, it must to subdivide the market it faced, estimate the demand flexibility of each segment market and the number of substitute, and the short-term cost function of each product, of course difference in product is very important.More>
2003, 3(4): 85-88.
Freeway OD matrices estimation with on/off ramps traffic counts
CHANG Yun-tao, PENG Guo-xiong, YANG Xiao-guang
Abstract: This paper analyzed the relationship between OD matrices and on/off ramps of freeway, and built the freeway ramp flow relation model and freeway ramps system state space model. Based on analyzing the characters and constraint conditions of OD matrices, this paper applied the constrained Kalman filter(CKF) to estimate OD matrices. Simulation results indicate that CKF method performes much better than traditional Kalman filter(KF), and the output can trace time-variable OD matrix well.More>
2003, 3(4): 89-94, 99.
Traffic corridor control model of urban road
ZHANG Jian-song, CHEN Jian-yang, SUN Li-jun
Abstract: The corridor control model, which is usually used in freeway, was adopted to urban road control. Its applying situation and control strategy were analyzed when the total travel time was taken as control parameter. The constitute parts of total travel time were seperated. The minimization of total travel time as a control goal, its mathematical model and control program were developed. With an example, the results show that this control technology is an effective way to make the control system optimum,More>
2003, 3(4): 95-99.
Traffic flow capacity at unsignalized intersection of road
TAO Jing-hui, LI Xu-hong, MAO Hai-jun
Abstract: Based on the gap acceptance theory, the mixed traffic flow was analyzed with probability method. When the flow at major lane of unsignalized intersection follows two-class Erlang dis-tribution, the traffic capacity model of mixed flow at branch lane was developed. With an exam-ple, its calculation results were compared with the ones by other models. The results indicate that this model is more accurate, its error is 16.6%.More>
2003, 3(4): 100-103.
Adaptive thresholds edge detection of traffic image
XIAO Wang-xin, ZHANG Xue, HUANG Wei
Abstract: The edge of traffic image was detected with wavelet transform. Its scale influence, meteyard and adaptive thresholds were studied. Large scale filter was used to restrain and identify noise, while small scale fiter was used to precisely position for image edge. A quadric B-spline wavelet was constructed, which has eminent characters, such as narrow support, small computation amount. Simulation results prove its effect is better than that of classical Sobel operator, the former method has good anti-noise and adaptive ability.More>
2003, 3(4): 104-107.
Realization of voice route guidance module of vehicle navigation system
HE Zhao-cheng, LIU Xu-qi, HONG Bo, LI Jun, HUANG Zhong-zhou, YU Zhi
Abstract: This paper studied the relation between route guidance module and other modules in vehicle navigation system. The advantages of voice route guidance function were presented. The main algorithm steps based on GIS were developed, with the route planning module and the positioning module, the methods to realize three key sub-modules: generation of driving instruction, planned route track and generation of voice guidance information were discussed. Its application results show that the module can accuraely generate voice guidance information.More>
2003, 3(4): 108-111.
Hybrid genetic algorithm of vehicle routing with time windows
SONG Hou-bing, CAI Yuan-li
Abstract: Based on standard genetic algorithm, each chromosome was associated with more informations, the λ-interchange local search method was applied to developed a new algorithm, named hybrid genetic algorithm, for solving vehicle routing. It is found that the total journey computed by hybrid algorithm is 162 km, and the journey by standard algorithm is 182 km. The results indicate that the hybrid algorithm can find better solution than standard genetic algorithm, the necessary journey is shorten greatly, the transportation cost can be reduced effectively.More>
2003, 3(4): 112-115.
Review on decision making for international shipping investment
SHAO Rui-qing
Abstract: The studies in the field of decision making for international shipping investment were reviewed. It is pointed out that the study on traditional method has goten a lot of achievements, the quantitative evaluation on decision making method has been used widely, but the study way based on option has not been carried out enough. The orientation of future research and the focal subjects in this field are pointed out.More>
2003, 3(4): 116-120.