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Journal of Jilin University(Engineering and Technology Edition)
ISSN 1671-5497
CN 22-1341/T
主 任:陈永杰
编 辑:张祥合 曹 敏  程仲基
    赵莹莹 赵浩宇
电 话:0431-85095297
地 址:长春市吉林大学南岭校区

Table of Content
01 November 2010, Volume 40 Issue 06
Power matching and simulation for plugin hybrid electric bus
WANG Jia-Xue, WANG Qing-Nian, WU Dong, YANG Fang, ZHAO Zi-Liang
吉林大学学报(工学版). 2010, 40 (06):  1465-1472. 
Abstract ( 1316 )   PDF (863KB) ( 806 )  

The basic configuration of the plugin hybrid electric bus(PIHEB) was analyzed and a new method of power matching for PIHEB was proposed based on the combination of theoretical calculation and the power demand analysis during actual driving cycle of the bus. The theoretical and simulational studies showed that the new method comprehensively considers the power demand on vehicle during actual driving cycle, overcomes the disadvantage of point power matching only by theoretical calculation, makes the power matching of PIHEB optimal.

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Factors influencing |regenerative braking of parallel hydraulic hybrid vehicles
LIU Tao, LIU Qing-He, JIANG Ji-Hai
吉林大学学报(工学版). 2010, 40 (06):  1473-1477. 
Abstract ( 1310 )   PDF (472KB) ( 632 )  

The energy losses in the parallel hydraulic hybrid vehicle(PHHV) during braking were analyzed and the magor directions of the energysaving research for the hydraulic hybrid power system were derived. The effects of the driving mode, the driving cycle, the transmission ratio of torque coupler on the regenerative braking behavior of PHHV were studied by contrast calculation and simulation.The results showed that adopting the front wheel driving mode, increasing appropriately the transmission ratio of torque coupler and selecting reasonably the volume and working pressure of hydraulic accumulator are helpful to improve the regenerative braking performance of PHHV, especially under urban driving cycles.

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Control algorithm for vehicle electronic stability program based on brake wheel cylinder hydraulic pressure estimation
LI Jing, SHA Hong-Liang, WANG Bo-Beng, LIU Wei, LIU Guan-Ting
吉林大学学报(工学版). 2010, 40 (06):  1478-1481. 
Abstract ( 1025 )   PDF (433KB) ( 568 )  

A vehicle wheel hydraulic cylinder pressure estimation algorithm was presented based on query mode, and a control algorithm of brake actuator with pressure feedback was devised for electronic stability program(ESP). The relationship between the duty ratio of wheel cylinder solenoid valves for increasing and decreasing pressure and the pressure in the wheel cylinder was established using hardwareintheloop tests. A wheel hydraulic cylinder pressure estimation algorithm was achieved. The tests showed that the estimated cylinder pressures are in good agreement with their actual values, and the proposed ESP with feedback by estimated pressure improves the vehicle handling and stability performance at extreme steering conditions.

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Damping characteristic and its influence factors in energy regenerative suspension
YU Chang-Miao, WANG Wei-Hua, WANG Qing-Nian
吉林大学学报(工学版). 2010, 40 (06):  1482-1486. 
Abstract ( 1237 )   PDF (389KB) ( 680 )  

A model was built for the energy regenerative suspension(ERS) using softwares MATLAB/SIMULINK and CARSIM. The noload voltage characteristic of the ERS was studied. The relationships between the damping factor and the charging capacitance as well as the compression speed were analyzed. The damping characteristic curves of the ERS were obtained. The results showed that the damping performance of ERS satisfies the need of the passenger car, at the same time it can recover some of the car vibration energy.

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Design optimization of vehicle crashworthiness based on new MDO method
ZHAO Qian, CHEN Xiao-Kai, LIN Yi
吉林大学学报(工学版). 2010, 40 (06):  1487-1491. 
Abstract ( 1034 )   PDF (468KB) ( 606 )  

The multidisciplinary design optimization(MDO) methods can be used to solve the design problems of largescale complex engineering system effectively.In order to deal well with the quasiseparable MDO problems usually encountered,a two-level alternating optimization method based on penalty function(PAO) method was introduced.PAO is based on decomposition and coordination strategy,that is,the quasiseparable MDO problem is decomposed into a system level problem and many subsystem level problems,and then the  subsystem level problems are solved alternately to achieve the consistency among all subsystems.PAO was first used to the design optimization of a vehicle crashworthiness problem.Results revealed that this method is effective.
Key words:vehicle engineering;multidisciplinary design optimization methods;decomposition and coordination strategy;quasiseparable MDO problems;vehicle crashworthiness;penalty function

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Lightweight design of vehicle body structure based on internal force optimization
NA Jing-Xin, HE Hong-Jun, YAN Ya-Kun, CHEN Li-Jun
吉林大学学报(工学版). 2010, 40 (06):  1492-1496. 
Abstract ( 1120 )   PDF (502KB) ( 646 )  

According to the fact that the skeleton of the integral vehicle body is mainly made up of slender bars and the load capacity of the bar is much better than that of any nonaxial loaded components, a lightweight design concept was proposed for vehicle body based on the optimization of internal forces in structure. The force flow in the vehicle body structure was analyzed to obtain the load bearing of the integral structure and its major components, the regions of high stress and low stress were found, and the internal forces and stresses in these regions were analyzed. The lightweight potential was tapped from the optimization of force bearing pattern. As a case example, a lightweight optimization was made for a integral coach body, and the mass of the body was reduced by about 220 kg due to the reduction of the highest stress.

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Reformed collaborative optimization method and its application
LI Bang-Guo, CHEN Xiao-Kai, LIN Yi
吉林大学学报(工学版). 2010, 40 (06):  1497-1501. 
Abstract ( 1025 )   PDF (450KB) ( 555 )  

The COM is characterized by some computational difficulties in its application. The sources of the computational difficulties were analyzed and several alleviators were reviewed. An improved COM was suggested by modifying the quadratic compatibility in the system level, might be called as the COM based on the dynamic constraints in the system level. The new method updated the constraints in the system level, can avoid the computational difficulties from the system level constraints of the original COM. The improved COM was used to the optimal design of a gear reducer. The results showed that the improved COM is characterized by high robustness, reliability and anvergence speed.

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Evaluation method and mathematical model of vehicle interior sound quality during acceleration
GAO Yin-Han, SUN Qiang, LIANG Jie, TANG Rong-Jiang
吉林大学学报(工学版). 2010, 40 (06):  1502-1506. 
Abstract ( 978 )   PDF (352KB) ( 651 )  

A software system was developed for subjective evaluation test of vehicle interior sound quality under nonsteady driving condition. It was employed for the subjective evaluation of the interior noises of six types of cars during acceleration from 50 km/h to 120 km/h. The subjective rate of each sample was obtained by this software first. Then several primary objective psychoacoustical parameters of these samples were calculated. Using correlation analysis and multidimensional linear regression analysis, a mathematical model of sound quality was established, in which the loudness and roughness were taken as the variables. The subjective evaluation test was carried out for other six samples under different acceleration condition to verify the accuracy of the proposed model. It was shown that there exists a strong correlation between the model evaluation result and subjective evaluation result, which validates the model.

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Effects of GTL/diesel blended fuel on combustion from small diesel engine
SUN Wan-Chen, LI Guo-Liang, MA Yi-Gong, XIE Fang-Chi, MENG De-Jun, LIU Zhong-Chang
吉林大学学报(工学版). 2010, 40 (06):  1507-1512. 
Abstract ( 1052 )   PDF (503KB) ( 552 )  

The effects of the blending fraction of gastoliquid(GTL) fuel in the GTL/diesel blended fuel on the combustion characteristic of a small diesel engine under steady operating conditions and transient conditions of fixed speed and increasing torque were studied experimentally using a homemade transient operation control and measure system for diesel engine. The results showed that the effects of the GTL fraction in the blended fuel on the combustion parameters demonstrate a similar tendency under steady and fixed speed and increasing torque operating conditions. Increase of GTL fraction leads to advanced ignition start, shorter ignition delay period, shorter premixed combustion period, reduced incylinder peak combustion pressure and reduced heat release rate. All these changes are good for the reduction of NOx emissions and combustion noise. Adding a little of GTL fuel into diesel fuel increases the combustion duration of the diesel engine, but the duration decreases with the increase of the GTL fraction. The combustion duration of the engine using pure TGL fuel is equivalent to that using pure diesel fuel.

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Optimization method of time intervals of data for GPS equipped floating car
JIANG Gui-Yan, NIU Shi-Feng, CHANG An-De, CONG Yu-Liang
吉林大学学报(工学版). 2010, 40 (06):  1513-1517. 
Abstract ( 1091 )   PDF (325KB) ( 593 )  

Aiming at the problem that the time intervals of sampling and transmitting of GPS data of the traffic information collection system based on the GPS equipped floating car were chosen by subjective experiences, and the related theoretical studies divoreed more or less from the practical application, judging indexes reflecting the relationship between the quality of the traffic information and the time intervals of GPS data sampling and transmitting were suggested, optimization methods were designed for these two time intervals and verified with measured data. The results showed that the best time intervals can be determined intuitively using the suggested methods, providing a reliable basis for the parameter setting of the GPS floating car traffic information collection system.

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Prediction method of highway induced passenger flow volume adapting ChangchunJilin high speed railway project
WANG Jing, WANG Dian-Hai, QU Zhao-Wei
吉林大学学报(工学版). 2010, 40 (06):  1518-1522. 
Abstract ( 1083 )   PDF (356KB) ( 514 )  

The variation of highway passenger flow volume induced by ChangchunJilin highspeed railway project was determined through analysis of related data to ascertain the impacts of the building of this railway on the regional highway passenger transportation modes in Jilin province. The highway passenger flow volumes induced in the affected areas were predicted using some proper calculation models. The results provided a theoretical basis for the feasibility study of ChangchunJilin highspeed railway project and a technical support for the corresponding adjustment of regional highway passenger transportation systems.

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Resident trip mode structure model based on selforganization theory
ZHAO Bei, ZHAO Shu-Zhi, ZHU Yong-Gang, NI Tong-He
吉林大学学报(工学版). 2010, 40 (06):  1523-1527. 
Abstract ( 920 )   PDF (393KB) ( 598 )  

The applicability of the selforganization theory to the study of the resident trip mode selection was analyzed. The control variables and the order parameters were advanced from the view of synergy. The system transformation was described mathematically and an order parameter model was built. Taking the case of Changchun city as an example,its resident trip mode structure was described, and its order parameter equations were derived, providing a basis for formulation of the traffic management measures.

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Road network dynamic splitting based on timespace characteristic of traffic flow
DONG Chun-Jiao, SHAO Chun-Fu, CHEN Xiao-Ming, LI Juan
吉林大学学报(工学版). 2010, 40 (06):  1528-1532. 
Abstract ( 1084 )   PDF (435KB) ( 535 )  

A road network dynamic splitting method was proposed based on the timespace characteristic of traffic flow. A general space distance model was built based on the space characteristic of the road network to measure the distance between the road sections. The RQ factor analysis method was introduced to split the road network in space according to the general space distance between the road sections. Taking the realtimely acquired traffic flow information as the input, the road network dynamic splitting was realized based on the time characteristic of traffic flow. A case analysis was performed for a urban highspeed road network, the splitting results showed that these is strong similarity between the traffic flows of sections of subroad network.

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Sound as countermeasure against driving fatigue:simulator study
MAO Ke-Dun, ZHAO Xiao-Hua, FANG Rui-Xue, RONG Jian, LIU Xiao-Ming
吉林大学学报(工学版). 2010, 40 (06):  1533-1537. 
Abstract ( 902 )   PDF (412KB) ( 453 )  

A driving simulator experiment was carried out to validate the effect of the environmental sound as a fatigue countermeasure. Various types of the simulating sound rource were synthesized by different intensities, frequencies, and durations of sound. The monotonow scene at midday was chosen to do experiment because of initiating easily the fatigue symplom. The eye movement and the other facial features were used as the criteria for fatigue judgement. The sound stimuli were given as the fatigue symptom appeared, and the variations of the driver physiological signals including the electroencephalogram, the electwcardiogram, and the eye movement and his driving performance were analyzed before and during the sound stimulation. The results showed the alerting reaction exists for the monotonous sound stimulation when the driver is in the fatigue state, but the alert only lasts for a few minutes. The type of the stimulating sound affects significantly  on the result of stimulation. Therefore, it is necessary to further study the effects of various factors of the sound against the driving fatigue and establish a lasting, alerting sound combination as an effective driving fatigul countermeasure.

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Feature description and its solution of asphalt road pavement micro-topography based on fractal theory
WANG Wei-Feng, YAN Xin-Ping, CHU Xiu-Min, XIE Lei, MA Yu-Lin
吉林大学学报(工学版). 2010, 40 (06):  1538-1542. 
Abstract ( 1005 )   PDF (532KB) ( 519 )  

The texture of the asphalt road pavement may be described using the fractal theory due to its complexity and selfsimilarity on microscale. The microtopography of the asphalt pavement structure depths in the vertical direction was analyzed by the fractal interpolation method based on the iterated function. The optimal vertical scaling factors of the affine transformation in the iterated function system were acquired by a genetic algorithm to calculate the fractal dimensions. The profile altitude data of 4 different alphalt pavement specimens were acquired by a highprecision laser range finder. The acquired data were used to analyze the relationships between the fractal dimension and the pavement mean structure depth, the arithmetic mean error, as well as the rootmeansquare error, and to simulate the fractal curve of pavement structure depth variation by the interpolation functions.

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Timedependent reliability of concrete pier of Tsingtao bay bridge
JIA Chao, JI Sheng-Zhen, ZHANG Feng
吉林大学学报(工学版). 2010, 40 (06):  1543-1549. 
Abstract ( 953 )   PDF (705KB) ( 606 )  

The timedependent reliability problem of the concrete structure in northern sea regions of China was discussed. The degradation behaviors of the mechanical properties such as Young’s modulus, compressive strength and tensile strength of the concrete structure after the freezethaw cycles were revealed through a great deal of inlab freezethaw tests. The mechanical parameter degradation of the concrete pier with the freezethaw cycle number were obtained, and the strengthtime degradation laws were abtained. A timedependent reliability calculation method of the concrete structure in the freezethaw environment was proposed. The lower concrete structure of the pier of Cangkou searoute of Tsingdao Bay bridge were analyzed numerically by the finite element reliability theory and the proposed method, and the reliability index variation with time was obtained, providing a reference for the engineering maintenance decision making of the pier.

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Bending stiffness of composite slim beam with deep deck
SHI Yong-Jiu, YANG Lu, WANG Yuan-Qing, LI Qiu-Zhe
吉林大学学报(工学版). 2010, 40 (06):  1550-1555. 
Abstract ( 943 )   PDF (595KB) ( 516 )  

The bending behavior of the simplysupported composite slim beam with deep deck and the stress and strain distributions in sections were investigated by test and FEM numerical simulation using software ANSYS.The results indicated that the sections of the beam remain flat during the elastic deformation stage, so the classical beam theory in material mechanics was used to analyze the bending stiffness of beam sections and the average stiffness of the simplysupported beam in combination with the measuring data in tests. A formula to calculate the bending stiffness of the simplysupported composite slim beam with deep deck was proposed.

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Perturbation stochastic local orthogonal elementfree Galerkin method
MENG Guang-Wei, ZHOU Li-Ming, LI Feng, SHA Li-Rong
吉林大学学报(工学版). 2010, 40 (06):  1556-1561. 
Abstract ( 834 )   PDF (802KB) ( 534 )  

A pertubation stochastic local orthogonal elementfree Galerkin method was proposed based on the study of the local orthogonal elementfree Galerkin method and the second order pertubation method. The proposed method needs only the node information instead of the connection of the nodes to form elements. It is not necessary that the discrete point of the stochastic field coincides with the discrete node and without restraint by the element. It can guarantee the attributes of the orthogonal basis function without need of matrix reversal, and its derivatives have general and simple expressions, being convenient to program. The essential boundary conditions are imposed by the penalty function method which does not increase the quantity of unknown variables, converges fast. A case example on analysis of a static mechanical problem for a structure with stochastic parameters showed that the proposed method is correct and effective, providing a new method for solving the stochastic response problem of the structure.

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Electroless NiWP coating on magnesium alloy
ZHANG Wen-Xue, JIANG Zhong-Hao, LIAN Jian-She
吉林大学学报(工学版). 2010, 40 (06):  1562-1566. 
Abstract ( 881 )   PDF (652KB) ( 529 )  

Electroless NiWP coating with high content of W has been developed on chromiumfree pretreated AZ91D magnesium alloy by using an alkalinecitratebased baths, in which nickel sulphate and sodium tungstate were used as metal ion sources, and sodium hypophosphite was used as a reducing agent. One important modification of the NiWP electroless bath is the addition of sodium carbonate, which works as complexing agent, accelerator and buffer. Codeposition of tungsten resulted in ternary NiWP coating with phosphorus content of 4.84 wt.% and tungsten content of 4.5 wt.%, respectively. Both the electrochemical analysis and the porosity test revealed that the ternary NiWP coating exhibited good corrosion resistance in protecting magnesium alloy.

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Microstructure and propoerties of the coating formed by laser cladding of Al-Ti-C powders on magnesium
吉林大学学报(工学版). 2010, 40 (06):  1567-1571. 
Abstract ( 985 )   PDF (805KB) ( 489 )  

An attempt has been made to enhance the wear resistance of AZ91 magnesium alloy by laser surface cladding AlTiC powders(in the weight ration Ti∶C=1∶1, Al content ranges from 20%-40%) using a 1 kW Nd:YAG pulsed laser. The experiment was performed using different laser power densities of 1.67, 1.89, 2.20, 2.65 and 3.14×109 W/m2, and scan speed ranging from 0.5 mm/s to 2.5 mm/s. The microstructure of the modified surface layer was examined, the hardness and wear resistance were measured. The results showed that a cladding layer with a hardness of HV210 and 4 times as wear resistant as the untreated material was prepared using a powder containing 40% Al under the laser scan speed of 1.0 mm/s, laser power density of 2.20×109 W/m2.

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Structure and magnetic properties of FePt/Ag thin film
LI Hai-Bo, ZHANG Yu-Mei, LIU Mei, YU Yong-Sheng, ZHANG Wei, FEI Wei-Dong
吉林大学学报(工学版). 2010, 40 (06):  1572-1576. 
Abstract ( 1199 )   PDF (468KB) ( 475 )  

The FeAg and FePt/Ag thin films were deposited on SiO2〈0001〉substrates by direct current magnetron sputtering at room temperature.L10FePt granular films with high coercivity have been obtained after vacuum annealing at various temperature. The results indicated that adding Ag could reduce the FePt ordering temperature effectively,the transformation from disorder to order phase took place when the films were annealed at 300 ℃. With increasing the annealing temperature, the chemical ordering degree increased while the surface roughness of the samples decreased, forming uniform granular films.

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Fabrication of microgear shaft on microEDM
CHU Xu-Yang, DI Shi-Chun, WANG Zhen-Long
吉林大学学报(工学版). 2010, 40 (06):  1577-1582. 
Abstract ( 766 )   PDF (570KB) ( 463 )  

Micro Electrical Discharge Machining (microEDM) process and micro Wire Electrical Discharge Machining (microWEDM) process have been proven to be appropriate techniques for fabrication of threedimensional micro parts and high aspect ratio micro structures. The structural feature of microgear shaft and the machining characteristics of microEDM and microWEDM were analyzed in this paper. Then a process flow for fabrication of microgear shaft was proposed, which combines microEDM and microWEDM, and the machining accuracy and efficiency were analyzed. A microgear shaft with pith diameter of 350 μm was fabricated by this method.

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Effect of Rops stiffness| shope angle and seatbelt restraint on operator injury in rollover of engineering vehicle
SI Jun-De, WANG Guo-Jiang, WEI Xiu-Ling, WANG Ji-Xin
吉林大学学报(工学版). 2010, 40 (06):  1583-1588. 
Abstract ( 829 )   PDF (499KB) ( 544 )  

The dynamic responses of the driver in a ZL50 loader during rollover process on 30° and 45° slopes were studied using the finite element analysis and the multirigidbody method. The effects of the stiffness of the rollover prevention structure(ROPS), the slope gradient, and the seatbelt restraint on driver injury were analyzed taking the human body injury risks as evaluation indexes. The results showed that on the premise of maintaining a necessary survival space for the driver, the human body injury alleviates with decrease of ROPS stiffness. The change of slope gradient leads to the various injury position of human body. The 4point seatbelt decreases effectively the head injury risk, but the type of seatbelt has little impact on neck injury.

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Multi-layer monitoring and open CNC system based on fieldbus
LIU Qing-Jian, WANG Tai-Yong, XU Yue, ZHI Jin-Zhang, LIU Zhen-Zhong
吉林大学学报(工学版). 2010, 40 (06):  1589-1594. 
Abstract ( 876 )   PDF (526KB) ( 633 )  

Facing the trends of the computerized numerical control(CNC) systems towards multifunction and high integration possible leading to realtimeness and robustness problems caused by condensed information exchange, an open CNC system configuration was proposed based on ProfibusDP and PXI buses. The time behavior of the buses was analyzed, it was found they meet the demand for high speed and high precision. The controller uses the IPC framework, accomplishes the software function using the component technology, realize the rapid reconstruction of CNC by different allocation of functional components. The functions of state monitoring, failure diagnosis and processing optimization are fused into the CNC system using a 3layer network. The prototyped machine based on IPC framework proved the feasibility of the CNC scheme.

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Simplified matrix model for load distribution of highspeed ball bearing
ZHAO Chun-Jiang, LIANG Bo, GE Shi-Dong, HUANG Qing-Xue
吉林大学学报(工学版). 2010, 40 (06):  1595-1598. 
Abstract ( 888 )   PDF (392KB) ( 526 )  

he variation features of the geometric and kinetic parameters of the highspeed rolling body were given based on the conventional calculation method of the load distribution of the highspeed ball bearing. According to these features, a new calculation method was suggested to simplify the equation group of the highspeed ball bearing load distribution into a matrix model of the linkage finite element method(FEM). It was discovered that some of the parameters of the linkage FEM model are independant variables and some are known variables  in the calculation process through the analysis of the equilibrium equation of the bearing inner ring. Therefore, the FEM model could be reduced into a 4order matrix model, simplifying the load distribution calculation to a great extent. The simplified method was suitable for the matrix solution on Matlab, the programing is simplified, the calculation speed increased, and the calculation stability was inproved. A case example showed that the fensibility and reasonableness of the proposed method instead of the conventional method.

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Static characteristic for |newstyle high stiffness externally pressurized spherical gas bearings
REN Di, WANG Zu-Wen, BAO Gang, YANG Qing-Jun
吉林大学学报(工学版). 2010, 40 (06):  1599-1603. 
Abstract ( 785 )   PDF (572KB) ( 523 )  

A new type of bearing structure with the ball size exceeding the socket size(can be called as the pressurized spherical gas bearing with interference fit) was developed. The 3dimensional finite volume method was used to calculate the static characteristic of the new bearing and its results were compared with those of the traditional bearings with snug fit and running fit. The comparison showed that the bearing capacity and the static stiffness of the new bearing with interference fit are much better than those of the traditional ones.

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Modal analysis of gear with bionic surface morphology
HAN Zhi-Wu, LV You, DONG Li-Chun, ZHANG Jun-Qiu, NIU Shi-Chao, MA Rong-Feng, REN Lou-Quan
吉林大学学报(工学版). 2010, 40 (06):  1604-1608. 
Abstract ( 1044 )   PDF (523KB) ( 630 )  

The highaccuracy parameterized involute spur gear model was established by using Pro/e software. Based on the engineering bionics and the finite element theory, the effect of the bionic surface morphology on the improvement of the dynamic performances of the gear was analyzed using MSC.Nastran software. By comparison of the modal analyses of ordinary gear and the gear with bionic surface morphology, the anterior 10 ranks of natural frequencies and mode shapes were calculated. The results show that the maximum amplitude of any rank of the anterior 10 ranks of the gear with bionic surface morphology is smaller than that of the ordinary gear. The natural frequency of the gear with bionic surface morphology decreases obviously and the trend of the natural frequency is much smoother than that of ordinary gear. The dynamic characteristics and the reliability of the gear have been ameliorated effectively.

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Interfacial dynamics simulation between soil and earthworm surface
LIU Guo-Min, JU Meng, LI Jian-Qiao
吉林大学学报(工学版). 2010, 40 (06):  1609-1613. 
Abstract ( 1007 )   PDF (542KB) ( 459 )  

A simulation model of the interfacial dynamics between soil and earthworm surface was developed by PFC2D software. The contact interface, the contact force field, the contact particle number and contact sliding resistance of smooth surface and corrugated surface was analyzed and compared. The results show that, when the resultant force of the friction and the particle backward thrust on the corrugated surface is less than the friction on the smooth surface, the corrugated surface can reduce the resistance. If the particle backward thrust on the corrugated surface is too large, the corrugated surface increases the resistance. When moving forward, the corrugated surface disturbs the soil more than the smooth surface. As the vertical load increases, the sliding resistances of both smooth and corrugated surfaces increase, but the dragreduction effect of the corrugated surface declines. The sliding resistance increases with the forward speed, but the increase trend of the corrugated surface is smaller than that of the smooth surface, and the dragreducing effect of the corrugated surface is more obvious at highspeed. The results also show that the dragreducing capability of the earthworm skin is related to the interfacial contact characteristics and external conditions. This study provides the reference for revealing the dragreduction mechanism of nonsmooth surface.

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Response patterns of gecko olfactory bulb neurons to amyl acetate stimulation
LIU Xiao-Qin, YUE Lin, TAN Hua, ZHU Ru-Peng
吉林大学学报(工学版). 2010, 40 (06):  1614-1618. 
Abstract ( 1206 )   PDF (599KB) ( 473 )  

The neural responses of Gekko gecko olfactory bulb to amyl acetate were examined by extracellular recording techniques.Responses of 275 neurons in 21 geckoes could be classified into 3 categories,no response (43.6%),suppression (4.7%),and excitation (51.7%).The excited neurons could be further classified into 4 subtypes by temporal patterns,long term excitation (34.5%),short term excitation (6.25%),delayed response (6.25%) and neurons excited when cancelling stimulation (4.7%).The neural responses elicited by amyl acetate could be found generally at the dorsal side of rostral part and the ventral side of caudal part in olfactory bulbs.The results provide basic information on locomotion modulation by stimulating the animal’s olfactory neural system.

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Effect of extrinsic regulators on growth and ginsenoside content of hairy roots of Panax ginseng
XU Li-Xin, ZHAO Shou-Jing, LIANG Yan-Long, QIAN Yan-Chun, JIN Shi-Kun
吉林大学学报(工学版). 2010, 40 (06):  1619-1623. 
Abstract ( 799 )   PDF (335KB) ( 534 )  

The effect of adding 2,4D, NAA, IBA, MJA and SA to cell suspension cultures on the growth, content of total saponins and ginsenoside Rb1 of Panax ginseng hairy roots were investigated. Results show that three phytohormones could improve the growth of the hairy roots and promote saponin accumulation in different degrees. Addition of IBA at the level of 0.5 mg/L could significantly promote the growth (50.73g/L per month), and saponin accumulation (saponin content of 3.31%) of the hairy roots and raise remarkably the proportion of ginsenoside Rb1 (Rb1 content of 2.293%) in the total saponins. Other two elicitors could not significantly promote the growth, but, with suitable concentrations, could promote saponin accumulation of the hairy roots. The two elicitors have good synergistic effect on the saponin accumulation. With the combination of 0.001mmol/L MJA and 0.001mmol/L SA, the accumulation of total ginsenosides of the hairy roots is higher than that with either elicitor alone.

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Factors influencing degree of substitution of hydroxyl groups of surfacemodified starch films with alkenyl succinic anhydrides
REN Li-Li, ZHOU Jiang, TONG Jin
吉林大学学报(工学版). 2010, 40 (06):  1624-1628. 
Abstract ( 1020 )   PDF (433KB) ( 536 )  

The surface of starch films was modified through esteritification using Dodecenyl Succinic Anhydride (DDSA) and Octenyl Succinic Anhydride (OSA) as reactants. Orthogonal test designs were carried out to investigate factors influencing degree of substitution of hydroxyl groups in the surface layer of starch films. The results show that when the surface of starch films was modified by DDSA, the concentration of DDSA in ethanol was found to be the primary parameter to affect the degree of substitution of hydroxyl groups. When the surface of starch films was modified by OSA, environment equilibrium humidity was found to be the primary parameter to affect the degree of substitution of hydroxyl groups. When the surface of starch films was modified by the mixture of DDSA and OSA, the concentration of alkaline aqueous solution was found to be the primary parameter to affect the degree of substitution of the hydroxyl groups.

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Dielectric properties of corn at vacuum drying condition
YIN Li-Yan, TUN Wen-Fu, ZHANG Ya-Qiu
吉林大学学报(工学版). 2010, 40 (06):  1629-1633. 
Abstract ( 920 )   PDF (450KB) ( 461 )  

Based on designing interdigital electrode capacitance detecting element,a vacuum dielectric testing system was constructed.Dielectric properties variation regularity of corn were studied and provided a foundation for process testing and control in vacuum drying.The results show that there were nonlinear correlation between the dielectric properties,temperature and vacuum.Dielectric constant and dielectric loss factor increases with vacuum degree and there curves shows similar “Z” shape and dielectric loss angle shows tangent reverse similar “Z” shape.Moisture content and temperature have great influence to dielectric properties;they were negative linear correlation with dielectric loss angle tangent.Moisture content has positive linear correlation with dielectric constant in the prime range of moisture content.The higher moisture is,the more distinct changes;Temperature has positive linear correlation with dielectric constant;Dielectric loss factor has a sharp drop with moisture content increasing and has an increasing tendency with temperature.

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Fuzzy spatial description logic and application
WANG Sheng-Sheng, LIU Da-You, WU Xia, XIE Qi, GUO Hao
吉林大学学报(工学版). 2010, 40 (06):  1634-1638. 
Abstract ( 1101 )   PDF (477KB) ( 532 )  

Geospatial semantic web has become a research hotspot. The uncertainty is an intrinsic property of spatial information. There has been no research to combine geospatial semantic web and uncertainty. The Fuzzy Spatial Description Logic (FSDL) is proposed in this study, which is based on spatial reasoning and fuzzy logic. It can be treated as a basic theory for uncertainty reasoning supported geospatial semantic web and spatial ontologies. FSDL augments the following features to classical description logic: the complex role forming predicate for describing spatial relation, the syntax and semantics for fuzzy concept and roles. The tableau algorithm and the soundness and completeness proofs are given. Finally fuzzy RCC5 relation is defined based on FSDL.

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Improved clustering algorithm in peertopeer environments
吉林大学学报(工学版). 2010, 40 (06):  1639-1643. 
Abstract ( 916 )   PDF (468KB) ( 482 )  

P2PKMeans algorithm is a distributed clustering algorithm in PeertoPeer (P2P) network. An improved data clustering algorithm, DKMeans, was proposed based on P2PKMeans algorithm. The proposed algorithm works in a localized asynchronous manner by communicating with the directly connected nodes without global synchronization. DKMeans decreases communication overhead of P2P network by saving cluster information of direct neighbors, thus reducing the total network communication cost. Compared with P2PKMeans, the traffic is much less using the proposed DKMeans and there is no degradation in accuracy. Furthermore, with the increase in nodes, the traffic growth rate of DKMeans is lower that of P2PKMeans.

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Classical optimal planning method based on compacted encodings
LV Shuai, LIU Lei, JIANG Hong, WEI Wei
吉林大学学报(工学版). 2010, 40 (06):  1644-1649. 
Abstract ( 1120 )   PDF (286KB) ( 567 )  

Based on Graphplanencoding, a new encoding called PMAbased encoding by reducing the mutex axioms of actions, is proposed. The soundness and completeness of the new encoding are justified. The preprocessing method for goal states during encoding solving process is also proposed. The corresponding planner called PMASP based on the above encoding is designed and implemented, and test with benchmarks adopted by International Planning Competition. Comparing with the planner SATPLAN2006, the experimental results demonstrate that, for both tested domains, the scales of encodings of PMASP are compacted and the solver efficiencies are improved. For sequential planning problem Blocks World, the scales of encodings of PMSSP are compacted nearly 40% and solver efficiencies are increased nearly two times. For parallel planning problem Logistics, the scales of encodings of PMASP are compacted more than 80%.

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Resource interlinking of semantic bioinformatics database based on ontology
LIU Yan-Bin, ZHOU Chun-Guang, ZHANG Zhong-Yi, ZHOU Xu, ZHAI Yan-Dong, ZOU Shu-Xue
吉林大学学报(工学版). 2010, 40 (06):  1650-1654. 
Abstract ( 968 )   PDF (437KB) ( 508 )  

Combining RDF informatics database with the domain knowledge, we proposes a resource interlinking method of the RDF database based on ontology. Also we design and implement the corresponding algorithms for resource interlinking and semantic similarity computing. Experimental results validate the proposed method and algorithm model.

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Emailworm propagation with user behavior and network topology
LIU Yan-Hang, SUN Xin, WANG Jian, LI Wei-Ping, ZHU Jian-Qi
吉林大学学报(工学版). 2010, 40 (06):  1655-1662. 
Abstract ( 1292 )   PDF (905KB) ( 685 )  

By introducing the effects of user behavior and network topology, a novel emailworm propagation simulation algorithm is presented. Also a practical simulation environment is established based on EnronEmailDataset for emailworm propagation simulation. Simulation results show that the proposed algorithm can describe the emailworm propagation behavior accurately. The impacts of network topology on emailworm propagation are analyzed and we found that the infected keynodes can speed up the worm propagation. Also four protection strategies are proposed and examined through experiments. Results show that the imposed protections on keynode can slower the worm propagation. Furthermore, a new emailworm propagation model, named TopoSIS, is built. Compared with the simulation results, this new model can predict the size of affected users accurately.

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Energyefficient clustering algorithm for wireless sensor networks
ZHANG Rui-Hua, CHENG He-You, JIA Zhi-Beng
吉林大学学报(工学版). 2010, 40 (06):  1663-1667. 
Abstract ( 1019 )   PDF (422KB) ( 623 )  

A maximumvotes and loadbalance clustering algorithm (VLCA) for wireless sensor network was proposed.The algorithm is completely distributed,and independent of network size and topology.Simulation results show that the VLCA can reduce the number of clusters by 20%-50% and prolong the lifetime of a sensor network.

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Transaction model of grid database
ZANG Xue-Bai, ZHAO Hai-Yang, WU Yang, LI Xiong-Fei
吉林大学学报(工学版). 2010, 40 (06):  1668-1672. 
Abstract ( 865 )   PDF (394KB) ( 508 )  

According to the characteristics of selfgovernment and dynamics under grid environment, a model algorithm of transaction processing is proposed. The algorithm defines the key transaction, does not differentiate between coordinators and participants, each node only returns the results to the node who assigns the task to it. When a node can not finish its task, the algorithm uses service discovery technology to detect the nodes that can supply the same service in realtime; thus the probability of successful completion of the services is increased. The algorithm takes into account the rollback operation after the exit of the nodes to ensure the reliability of the services. The algorithm is validated by Petri net.

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Blind identification for light source images based on inconsistency in light source direction
LV Ying-Da, SHEN Xuan-Jing, MIAO Jian, WANG Dan, CHEN Hai-Peng
吉林大学学报(工学版). 2010, 40 (06):  1673-1677. 
Abstract ( 1242 )   PDF (494KB) ( 709 )  

A new blind identification method is proposed for digital images generated under the irradiation of local light source. The direction of light source is calculated in accordance with the error function between measured intensity and calculated intensity, as well as the regularization term suitable for local light source model. The direction of the light source is taken as the criterion to determine the authenticity. 486 photos in the database of experiment images are tested, among which the rate of correct detection reaches up to 77.16%, and the minimum and maximum errors are 0.2° and 1.0° respectively.

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Preprocessing method for iris classification and rotation correction based on corner characteristics
LIU Jing, BAI Tao, KANG Hui
吉林大学学报(工学版). 2010, 40 (06):  1678-1682. 
Abstract ( 1212 )   PDF (606KB) ( 471 )  

An iris preprocessing method was proposed based on corner characteristics. Using the information of corner and grayscale in the corner neighborhood region, the type of relationship between the template image and identifying image is determined through the corresponding affine and similarity calculation. The method solves the problem of removing rotation (maintaining rotation invariance) in the division of the iris sample set and fine recognition. Experimental results indicate that the proposed method has good classification performance and rapid recognition speed. It can be taken as the initial preprocessing operation for reducing the search size and removing the rotation in the normalized phase.

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Small and dim target detection based on selective visual attention mechanism and curve detection method
SUN Jin-Qiu, ZHANG Yan-Ning, ZHOU Jun, JIANG Lei
吉林大学学报(工学版). 2010, 40 (06):  1683-1687. 
Abstract ( 1120 )   PDF (604KB) ( 486 )  

The selective visual attention mechanism and a curve detection method based on a model of comect the dots problem were introduced in the small and dim target detection in the deep space background. In the visual attention mechanism, the target grayscale and movement continual significance were fully taken into account to get the focus of attention integration map. The target trajectory was detected by a curve detection method based on the connect the dots problem model. The experiments proved that the suggested algorithm reduced significantly the processed information, demonstrated a strong antinoise performance, was suitable to detect the small and dim target in the low signaltonoise environment.

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Probabilistic prediction approach of heat load based on support vector interval regression
ZHANG Yong-Ming, CHEN Lie, QI Wei-Gui
吉林大学学报(工学版). 2010, 40 (06):  1693-1697. 
Abstract ( 827 )   PDF (559KB) ( 506 )  

A probabilistic prediction approach was proposed based on the support vector interval regression(SVIR). The initial parameters of the SVIR model are determined by the support vector regression, and its upper and lower bounds are identified by two radial basis function networks. The confidence intervals and the point prediction outputs can be obtained at the same time by the proposed approach. The validity and practicability of the proposed approach were proved by comparative simulations by the proposed model and the BP network model using the heat load data collected from a practical heat supply station.

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Gaussian profile filter based on approximating spline
吉林大学学报(工学版). 2010, 40 (06):  1698-1703. 
Abstract ( 805 )   PDF (568KB) ( 499 )  

To overcome the end effect generated by the convolution method of traditional Gaussian filter in obtaining surface midline, a new spline filter is constructed by variance difference to realize Gaussian filter. This algorithm, called spline realization of Gaussian filter, preserves both Gaussian filter and spline properties. This means that this filter not only accords with the transmission characteristics of ISO, but also restrains the end distortion on data sequence. The amplitude deviation between this algorithm and Gaussian filter falls the interval (-1.5%, +3.75%), which is smaller than the interval (-5.0%, +5.0%) of the recommended algorithm by ISO11562. In addition, using this kind of Gaussian algorithm, the computation of 11200 measured points takes only 100ms on current computer, which demonstrates the efficiency of the proposed algorithm.

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Stereo video matching with color proportion and temporal correlation for belief propagation
MA Xing, CHEN He-Xin, ZHAO Yan, MU Chun-Yang
吉林大学学报(工学版). 2010, 40 (06):  1704-1709. 
Abstract ( 1008 )   PDF (657KB) ( 554 )  

An improved stereo video matching method was proposed. First, Markov random field model was used to build the stereo disparity model. Then the intensity and color proportion were employed to compute the belief. Finally the disparity sequence was computed by temporal correlation refreshed disparity value locally. Real scene provided by Carnegie Mellon University was tested. Experimental results show that the matching result based on luminance and color proportion is more accurate than the one based on luminance only. Using the temporal correlation matching method the computing iteration time could be reduced by 83.3%, which can provide high efficient disparity sequence for stereo video compression and free view point rendering.

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H.264/SVC fast motion estimation algorithm for sample video
YANG Hong-Sheng, YANG Guang, MAO Hong-Yu, TIAN Di
吉林大学学报(工学版). 2010, 40 (06):  1710-1714. 
Abstract ( 797 )   PDF (331KB) ( 583 )  

A fast motion estimation algorithm based on adaptive search range is proposed for the H.264/SVC, applied in remote realtime transmission of sample images of electron microscopes and other scientific instruments. The macroblocks at the base layer and enhancement layer are classified according to the spatial and interlayer correlation. For the macroblocks of different types, an adaptive search range algorithm in both horizontal and vertical directions is designed based on macroblock motion vector difference. In addition, early termination algorithms are also designed for matching block searching and interframe prediction respectively. Experimental results for sample videos of different instruments show that, compared with the fast search algorithm of reference software JSVM9.17, the proposed algorithm can reduce the encoding time by 52%-68% and the search points by 81%-95%, with similar PSNR and bit rate.

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New coding method for ROI based on JPEG2000
HUANG Xin-Lin, WANG Gang, LIU Chun-Gang, YU Ying-Xin
吉林大学学报(工学版). 2010, 40 (06):  1715-1718. 
Abstract ( 1036 )   PDF (400KB) ( 439 )  

A new coding method based on JPEG2000 for Region of Interesting (ROI) was proposed. In this method the pixel value of the ROI was upscaled in time domain and periodically extended; afterward it was added to the pixel value of background (BG). Then based on the additive characteristics of wavelet transform, the BG wavelet transform coefficients were used to subtract the corresponding ROI coefficients after wavelet transform. The image was reconstructed in the receiver through the corresponding process. The new method has low computational complexity and eliminates the shortcoming of edge blurring produced by time domain upscaling method. Experimental results demonstrate the advantage of the new method. At the same compression rate, the subjective image quality of the new method is better than that of time domain upscaling method and the new method facilitates the receiver to understand the ROI.

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Novel method on antenna selection for downlink multiuser MIMO systems
GUO Wen-Zhuo, ZHANG Shu, REN Da-Meng
吉林大学学报(工学版). 2010, 40 (06):  1719-1723. 
Abstract ( 1012 )   PDF (441KB) ( 480 )  

For a multiuser precoding scheme based on the SignaltoJammingplusNoise Ratio (SJNR) maximization criterion,closedform expressions of its beamforming weights and SJNR are derived.Furthermore,using these analytical expressions,an efficient antenna selection algorithm of high performance and its low complexity version are presented.Simulation results show that,compared with the conventional zeroforcing precoding method,the proposed antenna selection scheme based on the max SJNR criterion,can achieve lower BitError Ratio (BER),and therefore outperforms the zeroforcing method comprehensively.

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Design of a novel receiver for turboCPM system
XUE Rui, ZHAO Dan-Feng, ZHANG Ying
吉林大学学报(工学版). 2010, 40 (06):  1724-1728. 
Abstract ( 913 )   PDF (582KB) ( 481 )  

Based on the decomposed model of Continuous Phase Modulation (CPM), CMP is divided into a Continuous Phase Encoder (CPE) and a Memoryless Modulator (MM). Using the memorial and recursive characters of CPE, combining with external turbo code and random interleaver, the model of turboCMP system is established. Making use of the soft information output character of the system's demodulator and decoder, an iterative detection receiver based on the SISO algorithm is proposed. The effects of the parameters of the turboCMP system on its performance are studied. Theoretical analysis and simulation results show that the proposed receiver can improve the convergence of iteration, and reduce the errorfloor and the biterrorrate effectively than that of traditional concatenated receiver under the condition of low signaltonoise ratio.

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Key techniques of baseband control in CAPS simulator
WU Jian-Feng, HU Yong-Hui, MA Hong-Jiao, HE Zai-Min, WANG Kang, WANG Ji-Gang
吉林大学学报(工学版). 2010, 40 (06):  1729-1734. 
Abstract ( 1084 )   PDF (556KB) ( 529 )  

The research of the key techniques of baseband control is of great importance based on China Area Positioning System (CAPS) as the research platform. The system framework of the simulator is developed. A signal simulator of the CAPS was studied. The general block diagram was given, and the function of each module was divided and planned. The generation of satellite position parameters, the simulation of the ionosphere delay. The control of carrier DCO and code DCO are the key techniques that must be solved for the development of the CAPS simulator. In accordance with the characteristics of CAPS, the formulas of the relevant parameters were given. Based on these techniques, the CAPS simulator was developed. Test results show that the design is feasible, and the CAPS simulator can be applied to test the performance of the receiver on signal acquisition, signal tracking and positioning.

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Measurement delay effect on INS/GPS/DVL hybrid navigation system and calibration method analysis
ZHANG Tao, XU Xiao-Su
吉林大学学报(工学版). 2010, 40 (06):  1735-1740. 
Abstract ( 920 )   PDF (558KB) ( 519 )  

The affecting extent of measurement delay on the accuracy of INS/GPS/DVL hybrid navigation system was analyzed. It was shown that the heading error is a result of the measurement delay and it influences the forward accelerometer bias. The software and hardware calibration methods were proposed. They were the means of time tags and the crosscorrelation coefficients. The measurement delay was estimated then observation values were corrected under the conditions that no large changes were required for the hardware and algorithm. Several simulations were carried out in the case with and without measurement delay and after calibration compensation. The results show that by the proposed method the measurement delay error can be exactly estimated and there is almost no difference between each system precision with and without the measurement delay.

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