西南交通大学学报

WU Zhenye, SONG Tiansheng, ZHAO Ke

2006, 19(3): 269-272.

[Abstract](1460)

Abstract:
The characteristic of container routing problem was analyzed.A stochastic programming model was established for selection of container shipping routes,and in the model uncertainty in container demands was taken into consideration.The maximum profit of transportation was taken as target function,and the major constraints include the limitations due to the capacities of a route section and shipping capacity of carriers,and the demands on loaded and empty containers.The demands on loaded containers are stochastic.Chance-constrained programming method was used to solve the model.Simulation was conducted to validate the feasibility of the model.Simulation results indicate that shipping capacity and transportation price are main factors influencing container route selection,but a change in transportation price of a port pair has a little effect on container route selection.

Self-Adaptive Genetic Algorithm for Locomotive Diagram

HE Fengdao, LIANG Xiangyang, HE Dongyun

2006, 19(3): 273-278.

[Abstract](1641)

Abstract:
A mathematical model for a locomotive diagram of a train diagram with paired and non-paired trains was presented,and the optimized schedule was obtained with a genetic algorithm.The abilities of local search,convergence and optimization were raised with a two-point crossover operator and a knowledge-based mutation operator.The proposed method was tested over an actual problem of train diagram for a district on a railway line.The results show that the total time of locomotive operation and the required number of locomotives are reduced by about 5.7% and 7.7%,respectively.Another result shows that the proposed method reduces total time of locomotive operation compared with the method presented and for the same data taken in the same paper.

Effect of Air Turbulence on Airplane Turbulence

WANG Yongzhong

2006, 19(3): 279-283.

[Abstract](1453)

Abstract:
Equations with 6-degree-of-freedom motion were used to study the effect of air turbulence on vertical overload of an airplane.The transfer function of overload as the airplane flying in turbulence was deduced,and the airplane response to non-stationary air turbulence was analyzed.The results show that,at a subsonic speed,airplane turbulence increases with an increase in flying speed,and that a smaller airplane is affected more fiercely than a bigger one under the same air turbulence and weather condition.

Comprehensive Evaluation of Urban Rail Transit Network Planning Based on Green Transportation Principle

DU Shengpin, XIONG Ling, DING Weidong

2006, 19(3): 284-289.

[Abstract](1682)

Abstract:
To select the best urban rail transit network plan among the available ones,a comprehensive evaluation system was proposed based on the green transportation principle.An optimization algorithm for comprehensive weights was presented using analytic hierarchy process(AHP).The comprehensive weights were further modified using information entropy theory and the information on available plans,according to which the plans are sorted using TOPSIS(technique for order preference by similarity to ideal solution).Urban rail transit network plans for a city in China was taken as an example to show the procedure of proposed method,and the result accords with that given by experts.

Model and Algorithm for Vehicle Routing Problem with Backhauls and Time Windows

YIN Chuanzhong, BU Lei, PU Yun, ZHAO Yi

2006, 19(3): 290-295.

[Abstract](1598)

Abstract:
The characteristic of vehicle routing problem with backhauls and time windows was analyzed.An optimization model was proposed.The problem was simplified by setting a virtual collecting depot,from which the distance to the consignment depot is zero.To solve the model,an improved genetic algorithm was presented.An OX-crossover operator was designed to keep individual codes valid,and the reproduction operator based on Metropolis criteria was used to guarantee the diversity of individuals and to avoid premature convergence.Experimental computation indicates that the algorithm is valid and feasible.

Critical Effect of Decision Making for Logistics Outsourcing of Manufacturing Enterprises

SHUAI Bin, SUN Chaoyuan

2006, 19(3): 296-299.

[Abstract](1349)

Abstract:
There is a critical point,where the profit of a manufacturing enterprise increases or decreases dramatically,in the course of logistics outsourcing of the enterprise.The critical effect was described with a "white box" model of system theory.The input factors include total cost of logistics outsourcing,logistics service level and logistics management ability of the enterprise.The total cost of logistics outsourcing is determined according to the outsourcing scale,the service level consists of fill rate,ability of on-time distribution and a flexibility index,and the logistics management ability is evaluated with Delphi technique.The output of the "white box" is the total profit of the enterprise.The interaction between the input and output was discussed with system analysis method,and the critical point was determined and validated with Chow test method.

Spillover Effect and Determination of Innovation Time for Industrial Cluster

JIA Mingjiang, LIN Xiang

2006, 19(3): 300-304.

[Abstract](1220)

Abstract:
To understand the effect of technology spillover on innovation time for an industrial cluster,a spillover coefficient was added to the probability function of time for an innovation to succeed and to the linear function describing the correlation between innovation time and investment.An expected net revenue function of innovation by an industrial cluster was proposed.The partial derivatives of second order to the innovation time and spillover effect for the expected net revenue function were obtained to establish the partial derivative of first order for the correlation between the optimal innovation time and spillover coefficient.The symbolic analysis of the first order partial derivative shows that if there are a large number of competitors the optimal innovation time would be shortened with an increase in technology spillover coefficient,regardless the variation in innovation type,capital cost and risk of research and development.

Power Quadrilateral,Current Quadrilateral,Admittance Quadrilateral and Their Application

CAO Yuquan, BAI Lili, LI Mengda, YAN Weizhong

2006, 19(3): 305-309.

[Abstract](1369)

Abstract:
To solve problems that can not be solved using the power triangle,such as determining electric parameters in non-sinusoidal alternating-current circuits with harmonic currents,the power quadrilateral was proposed.A power quadrilateral consists of apparent power S,active power P,reactive power Q,and distortion power N,or is composed of a fundamental harmonic power triangle and a harmonic power triangle.Further,the current quadrilateral and admittance quadrilateral,as well as their similarity to the power quadrilateral in non-sinusoidal alternating-current circuits were derived.Electric parameters such as distortion power,harmonic distortion angle,total harmonic current,distortion admittance and harmonic admittance were calculated using the principle of the quadrilaterals and data collected in-situ.

Thermal Shutdown Circuit with Low Voltage and Low Power Consumption for Power Management IC

LIU Zhenfeng, FENG Quanyuan

2006, 19(3): 310-313.

[Abstract](1418)

Abstract:
A thermal shutdown circuit with low voltage and low power consumption was designed for power management ICs(integrated circuits).In the thermal shutdown circuit,the PN junction of a transistor was used as a temperature probe,where the switch-on voltage rises,and the variation of the switch-on voltage falls,with an increase in temperature.Reswitch-on temperature was depressed by a feedback mechanism to avoid temperature oscillation.Simulation with the parameters for a 0.6 μm BiCMOS IC was conducted.The results show that the circuit has ultra-low power consumption(the static current is about 0.5 μA);the errors of shutdown temperature are less than 1.00℃ when the shutdown temperature is set at 150℃ and the voltage of power source is 2.5 to 5.0 V;and the errors of reswitch-on temperature are less than 0.01℃ when the reswitch-on temperature is set at 135℃.

Offline E-cash System with Finite Circulation Period Based on Elliptic Curve

LU Rongbo, SU Hangli, HE Dake, MIAO Xianghua

2006, 19(3): 314-318.

[Abstract](1747)

Abstract:
To prevent e-cash from double-spending and unlimited increase in the records of databases,an improved offline e-cash system based on elliptic curve cryptography was proposed.The improved system utilizes good properties of elliptic curve cryptography system and adopts zero knowledge proof.Partial blind signature based on elliptic curve cryptography ensures that the e-cash is valid only in the period issued by the bank according to the withdrawal protocol,and the historical record of the e-cash that exceeds the valid period will be removed,which greatly reduce the amount of traffic and effort of calculation and improve the efficiency.The security of the system was improved by adopting the elliptic curve zero knowledge proof in the payment protocol.

Construction of Sequences with Zero Correlation Zone Based on Interleaved Technique

WANG Longye, TANG Xiaohu

2006, 19(3): 319-323,340.

[Abstract](1247)

Abstract:
Interleaved technique was used to construct a zero correlation zone(ZCZ),and a new method was proposed to design sequences with ZCZ.For a given perfect sequence a of a period L and an orthogonal matrix,a new sequence b is generated by interleaving the sequence a first,then a new ZCZ sequence set is obtained by extending b with the orthogonal matrix.The ZCZ sequence set constructed with the proposed method can reach or approach the mathematical bound, and the methods for construction of ternary,quadripahse or polyphase ZCZ sequences are unified with the proposed method.

Knowledge Discovery and Model Structure Selection Based on Rough Set Theory

ZENG Chuanhua, XU Yang, DU Yajun, XIE Weicheng

2006, 19(3): 324-328.

[Abstract](1547)

Abstract:
To select a proper decision model in intelligent decision,a method to acquire the knowledge of model selection and select a decision model by utilizing the knowledge was proposed based on the rough set theory.With this method,the decision table of models with continuous attribute values is acquired by setting parameters in the models randomly.Then,the relation between objects in the decision table is obtained by setting errors.From the relation,the reduction of attributes for the decision table is conducted by applying the rough set theory to gain decision rules.Based on these decision rules,a proper model can be selected. The feasibility of the proposed method has been illustrated using an example.

Algorithm for Visualization of Classification Results of Two-Category Data

WANG Xiaohong, WANG Xiaoru, LI Qunzhan

2006, 19(3): 329-334.

[Abstract](1541)

Abstract:
A new algorithm called support vector visualization(SVV) was proposed for visualization of classification results of two-category data to meet the need in some applications.The SVV algorithm is based on support vector machine(SVM) and self-organizing mapping(SOM).The result of SVV is a 2D map to visualize highdimensional data,the boundary of the two-category data,as well as the distance between a datum and the boundary.Compared with SOM and Sammon mapping algorithms,experimental results on two datasets with different separability verify the feasibility and effectiveness of the SVV algorithm.

Document Classification by Semi-supervised Online Learning Based on ART

XU Min, ZHANG Liping, ZHU Wujia

2006, 19(3): 335-340.

[Abstract](1442)

Abstract:
A semi-supervised learning system was proposed based on ART(adaptive resonance theory).It overcomes the limitation in the assumption in other semi-supervised learning algorithms that probabilistic distribution of data is known,and has the strong ability of learning new patterns and correcting errors because of stability and plasticity of the adaptive resonance theory.Higher adaptability of the system was advanced by setting vigilance parameters dynamically.Experimental results illustrate that the performances of the proposed system is better than the discriminant CEM(classification expectation maximization) algorithm,particularly when there are noise data and new patterns.

Max-Product Fuzzy Context-Free Grammar and Pushdown Automaton

XIE Yuemei, TIAN Liping, WAN Huifang

2006, 19(3): 341-343.

[Abstract](1245)

Abstract:
To extend the application fields of the present research,the concept of max-product fuzzy pushdown automaton was given on the basis of the study of max-product fuzzy grammars and automata,and the relationships between a max-product fuzzy context-free grammar and a max-product fuzzy pushdown automaton were investigated.The research shows that if and only if a fuzzy language is produced by a max-product fuzzy context-free grammar,it can be accepted by a max-product fuzzy pushdown automaton,so the max-product fuzzy context-free language can be recognized automatically.

Accuracy Analysis of Linear-Resection and Its Application in Control Measurement of Sutong Bridge

ZHOU Xizhen, YIN Renxiang

2006, 19(3): 344-348.

[Abstract](1243)

Abstract:
The calculation of coordinates and the accuracy analysis for two-point linearresection were conducted by taking the Sutong bridge as the research object,and the formation of two points were discussed.Furthermore,the coordinates and positional accuracy of three-or more-point linear-resection were calculated by a rigorous adjustment program.The research result indicates that three-or more-point linear-resection has a higher accuracy of mean square error of point positions and coordinates after they are adjusted than two-point linear-resection.The research results have been applied to the pass point measurement of the Sutong bridge and proven to be correct.

Dynamic Loading Test of Railway Long-Span Continuous Beam Bridge with High Piers

SHI Zhou, XIA Zhaoguang, GE Yumei

2006, 19(3): 349-354.

[Abstract](1598)

Abstract:
In order to inspect the actual dynamic responses of a bridge structure,dynamic loading tests were carried out on the Songtoujiang bridge,a railway continuous beam bridge with a main span of 100 m and a pier of 99 m in high.The natural vibration and dynamic responses of this bridge structure were tested respectively under the conditions that a train passes by and brakes on the bridge at different velocities.In addition,the testing results were compared with the results of vehicle-bridge coupling vibration analyses to show their sameness.The research results show that the bridge has enough vertical stiffness,transverse stiffness and strength,and the safety and comfortability are good though the passing train has an impact to the bridge structure.

Singular Perturbation Method for Solving Non-linear Vibration of Inclined Cables

RAN Zhihong, LI Qiao

2006, 19(3): 355-359.

[Abstract](1640)

Abstract:
To solve the difficult in the calculation of cable vibration,a non-linear dynamic model for inclined cables was set up by taking the geometrical non-linearity into account.The equation was solved using the singular perturbation method,and the analytical expressions of frequency and form function were derived.The expressions can be widely used for the fields of the measurement correction of cable force and the identification of parameters of a cable structure.The numerical calculations indicate that the expressions are simple and practical,and the calculation error is less than 0.5%.

Experimental Research and Theoretical Analysis of Working Performance of Steel-Concrete Composite Deck

ZHAN Yulin, ZHAO Renda, MAO Xueming, MOU Tingmin, FAN Bikun

2006, 19(3): 360-365.

[Abstract](1490)

Abstract:
An experiment was conducted on a simply supported steel-concrete composite deck to investigate the working performance of steel-concrete composite decks.The behavior of a perfobond strip shear connector and the reinforcement effect of steel fiber on concrete were investigated.Based on the experimental results,a theoretical analysis was conducted by taking the stress-strain relation of concrete and steel and the effects of steel fiber and transverse steel bars through the holes of perfobond strips into account.The result shows that no slip occurs between steel bars and concrete before the failure of the structure and thus this type of shear connectors can guarantee the integral working performance of a steel-concrete composite deck.

Fuzzy Comprehensive Evaluation of Durability of Existing Reinforced Concrete Arch Bridges

LI Zhenxin, GUO Fengzhe, QIAN Yongjiu

2006, 19(3): 366-370.

[Abstract](1661)

Abstract:
To reasonably evaluate the durability of existing reinforced concrete arch bridges the fuzzy mathematics was applied due to its complicated influencing factors. With this method,a reinforced concrete arch bridge is divided into the two layer levels of members and structures,and the corresponding membership functions are established to obtain the evaluation model for the durability of existing reinforced concrete arch bridges.This model has been used to evaluate the durability of an existing reinforced concrete arch bridge,and the evaluation result demonstrates the validity of this method.

Fatigue Test of Connection between Floor Beams and Monolithic Joints

LI Jun, LI Xiaozhen, REN Weiping, QIANG Shizhong

2006, 19(3): 371-375.

[Abstract](1718)

Abstract:
The full-scale fatigue test of connection structure details between floor beams and monolithic joints was carried out on the Caiyuanba Yangtze River bridge in Chongqing.Based on a finite element analysis,the test joints were selected,and the maximum and minimum fatigue loads were determined to be 660 and 50kN respectively.The test shows that no crack occurs in the model surface after two million time fatigue loadings and actual stress amplitude is 31.33MPa.The research shows that in the service life of this bridge structure,all the connection structure details between its floor beams and monolithic joints do not crack due to fatigue,so its fatigue strength meets the requirement.

3-D Elasto-plastic Numerical Simulation of Evolving Regularity of Structural Internal Force of Overlapped Tunnels

ZHENG Yuchao, QIU Wenge

2006, 19(3): 376-380.

[Abstract](1558)

Abstract:
To investigate the evolving regularity of structural internal force governed by tunneling of overlapped tunnels,3-D elastic-plastic numerical simulations were conducted on two overlapped tunnels in Laojie-Dajuyuan section of the Shenzhen metro.Two construction schemes,i.e.,up-to-down or down-to-up tunneling procedures,were taken into account.The research result shows that the circumferential internal force of the constructed tunnel deflects when an overlapped tunnel to be constructed is driven,and the longitudinal internal force appears.Evolution in the longitudinal internal force has a fluctuant,local and temporary characteristic with the driving of the subsequent tunnel.The longitudinal effect is confined within three times tunnel diameter in class Ⅲ surrounding rock and five times tunnel diameter in class Ⅴ surrounding rock.

Fatigue Strength of Bogie Frame of High-Speed Train under Spectrum Load

MI Caiying, LI Fu

2006, 19(3): 381-385.

[Abstract](1726)

Abstract:
To forecast fatigue strength or fatigue life of the bogie frame of a high-speed train effectively,a method for fatigue strength forecasting based on tested spectrum loads was proposed.First,with this method,test loads and their cycle numbers for fatigue strength of the bogie frame based on the criteria UIC515-4 and UIC615-4 are graded by using the rain-flow counting method.Second,tresses in the bogie frame under each level of loads are calculated by using the finite element method,multiaxial stresses are changed into a uniaxial stress,and the equivalent stress in the frame is calculated by using the Palmgren-Miner linear cumulative damage hypothesis.Finally,the fatigue strength or fatigue life of the frame is forecasted on the basis of the S-N fatigue life curve.A calculation example shows the validity of this method.

Criteria for Stability of Linear Neutral Delay Systems

ZHANG Keyue, YANG Suqin

2006, 19(3): 386-390.

[Abstract](1535)

Abstract:
The asymptotic stability of linear neutral delay systems was studied with an eigenfunction approach based on a frequency domain.New stability criteria,which are of delay-independent algebraic criteria,were derived by taking into consideration of the structural information of the coefficient matrices of the terms related to the system state,delay and differentiation.Compared with the existing ones,the new criteria relax the limitation on coefficient matrix and give larger stable parameter domains.The criteria for a numerical example,on which the conventional criteria fail,were obtained with the new criteria.

Time-Dependent Cyclic Behavior of Stainless Steel under Multiaxial Loading at Room Temperature

SHI Zhi, GAO Qing, KANG Guozheng, SUN Yafang

2006, 19(3): 391-395.

[Abstract](1347)

Abstract:
The time-dependent cyclic straining characteristic and ratcheting behavior of 1Cr18Ni9 stainless steel were investigated experimentally under non-proportional multiaxial cyclic loading at room temperature to research its dependence upon straining rate,stressing rate and loading paths.The results show that the cyclic straining behavior and ratcheting deformation of this material are markedly dependent on straining and stressing rates and have a time-dependent characteristic: the maximum equivalent stress increases with the increasing of straining rate under multiaxial straining,while the axial ratcheting strain increases with the decrease of stressing rate.Furthermore,loading paths have a great effect on the cyclic viscoplasticity behavior of the material: under multiaxial straining,the circular path causes the highest degree of non-proportional strain hardening in linear,rhombic and circular non-proportional loading paths adopted in the tests,then the rhombic path.Under multiaxial ratcheting tests,however,the circular path brings about a greater ratcheting strain than the rhombic path.

Period-Doubling Bifurcations of Period Motion of Two-Degree-of-Freedom Manipulators

ZHENG Xiaowu

2006, 19(3): 396-399.

[Abstract](1433)

Abstract:
To investigate the dynamic stability of a two-degree-of-freedom manipulator as a system,differential equations of motion for this system were established on the basis of the Lagrange equation,and perturbed differential equations with period coefficients were derived for the period motion of this system by applying the perturbance theory.Furthermore,the stability of the equilibrium point for the perturbed differential equations was analyzed by utilizing the Floquet theory,and the process of a period-doubling bifurcation after stability loss of the equilibrium point were investigated numerically.The research shows that a period-doubling bifurcation will occur if the eigen-matrix for the system has one eigenvalue-1 with the change of its parameters.

Smoothly Blending of Three Quadratic Algebraic Surfaces along Planar Sections

YU Kai, XUE Changhong

2006, 19(3): 400-403.

[Abstract](1123)

Abstract:
To expand the suitable conditions of the present blending methods,the problem of blending three quadratic algebraic surfaces along planar sections was transformed into a problem of ascertaining the existence of nonzero solution of homogeneous linear equations corresponding to these three quadratic algebraic surfaces under the condition without considering the existence of quadratic control surfaces.The existence conditions of cubic and quartic blending surfaces were given,i.e.,the ranks of the coefficient matrixes of their linear equations are less than 24 and 60 respectively,and the unconditioned existence of quintic blending surfaces was proved.Finally,the corresponding blending algorithm was presented.

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2006 Vol. 19, No. 3