bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved “Data Mules” Scheme Based on Controlled Working Area and Designed Trajectory
Authors: Wang Jie , Qiu Chen Xi , Qi Xiao Gang
Published: December 2010

Under the traditional “data Mules” scheme in Wireless Sensor Networks, nodes cannot send the data until the Mules move nearby, which leads to longer data delay. To overcome this shortcoming, this paper improve the “data Under the traditional “data Mules” scheme in Wireless Sensor Networks, nodes cannot send the data until the Mules move nearby, which leads to longer data delay. To overcome this shortcoming, this paper improve the “data Mules” through changing the working area of the Mules and designing its track. According to the mathematical analysis, we can find that reducing the working area of the Mules and its overlapped part can significantly reduced data delay and enhance the equity among sensor nodes. On the basis of this conclusion, a novel thinking and several recommendatory schemes are proposed. The simulation result shows that the new algorithms are significantly superior to traditional one in the aspects of data delay and nodes’ equity.
On Construction Mode for Training Electromechanical Professional Driven by Projects
Authors: Sun Yin Da , Xu Wen Qin , Zhou Bai Qing , Tao Wen Yong
Published: December 2010

The electromechanical professional have been recommended to be one of the ten urgently needed in the 21st century. According to problems existed in teaching, reforming ideas and its implementation are put forward to provide an operable, referencable, and propagable mode for the personnel training scheme.
Data Driven Multivariate Adaptive Regression Splines Based Simulation Optimization
Authors: Mao Hu Ping , Wu Yi Zhong , Chen Li Ping
Published: December 2010

This paper proposes a data driven based optimization approach which combines augmented Lagrangian method, MARS with effective data processing. In the approach, an expensive simulation run is required if and only if a nearby data point does not exist in the cumulatively growing database. Over time the database matures and is enriched as more and more optimizations have been performed. MARS is a self-adaptive regression process, which fits in with the multidimensional problems, and uses a modified recursive partitioning strategy to simplify high-dimensional problems into smaller yet highly accurate models. Combining the local response surface of MARS and augmented Lagrangian method improve sequential approximation optimization and reduce simulation times by effective data processing, yet maintain a low computational cost. The approach is applied to a six dimensional test function, a ten dimensional engineering problem and a two dimensional global test functions to demonstrate its feasibility and convergence, and yet some limiting properties.
CMM Inspect Path Planning for Precision Concave Revolved Surfaces
Authors: Pan Wei Min , Yu Yong Jian , Ma Wei , Liu Yong Gang
Published: December 2010

The revolved concave surfaces are widely applied to both optical equipments and aerodynamic domain. The revolved surface is measured by digitized measurement with the coordinate measuring machine (CMM) in this paper. A CMM inspecting path planning which is different from traditional measuring method for revolved surface is given. An automatic algorithm of digitization on a CNC coordinate measuring machine for an unknown revolved surface is present. At the same time, this method is proved effectiveness through a practical measuring example of an optical part. The Measuring process and the measuring results are illustrated in detail.
Identifying the Mastery Concepts in Linear Algebra by Using FCM-CM Algorithm
Authors: Liu Hsiang Chuan , Yu Yen Kuei , Yih Jeng Ming , Chen Chin Chun
Published: December 2010

Euclidean distance function based fuzzy clustering algorithms can only be used to detect spherical structural clusters. Gustafson-Kessel (GK) clustering algorithm and Gath-Geva (GG) clustering algorithm were developed to detect non-spherical structural clusters by employing Mahalanobis distance in objective function, however, both of them need to add some constrains for Mahalanobis distance. In this paper, the authors’ improved Fuzzy C-Means algorithm based on common Mahalanobis distance (FCM-CM) is used to identify the mastery concepts in linear algebra, for comparing the performances with other four partition algorithms; FCM-M, GG, GK, and FCM. The result shows that FCM-CM has better performance than others.
A Method for Maintenance Scheduling in Manufacturing Systems Based on TPM and MFOP
Authors: Long Jiang , Jiang Wei An
Published: December 2010

In order to improve the overall equipment effectiveness, a new method for maintenance scheduling in manufacturing systems using the philosophies of TPM and MFOP is presented in this paper，considering both the production process and maintenance operations of manufacturing equipment. An LCC analysis is also conducted for evaluating and searching for the optimal maintenance schedule.
Fuzzy Clustering Algorithm Based on Improved Particle Swarm Optimization and its Application
Authors: Li Xue Yong , Sun Jia Xia , Fu Jun Hui , Gao Guo Hong
Published: December 2010

A fuzzy clustering algorithm based on improved particle swarm optimization was proposed in this paper. First reduce dimension of solution space, separate it into smaller solution space. In separated solution space, use of improved particle swarm optimization algorithm to search the sub-optimal solution as a chromosome of whole particle,use improved PSO to search global optimal solution. The particle solve the problem that swarm algorithm easy to fall into local optimal solution in high dimensional space, and the problem that the fuzzy clustering algorithm is sensitive to initial value problems. Simulation results show the effectiveness of this algorithm.
The Think Aloud Experiment of the Designing Process of an Expert
Authors: Fan Qi , Zhang Ying , Jiang Ling Hua , Li Yuan , Hou Feng
Published: December 2010

Knowledge acquisition is the first step in building an expert system. However, it is very difficult to find out the problem-solving approaches from a human expert completely and correctly. Here we implemented the Think-aloud experiment with an expert in architecture. By coding and analyzing the designing process, other researchers could proceed our research and find out the cognitive models corresponded to the approaches and strategies of how experts solved the problems encountered during the normal designing process.
A Simple Method for Solving the Vehicle Power Demand
Authors: Zeng Xiao Hua , Wang Qing Nian , Zheng Shuai
Published: December 2010

The total power of vehicle power source is mainly decided by accelerating process. Because the current total power demand by the acceleration is not intuitive, in order to solve the shortcomings, this paper introduced an intuitive and reasonable solution method, which is derived in detail the theoretical equation. With the application of the equation, the total power of the vehicle can be calculated and designed directly through the acceleration demand, which has an important guiding significance for the automotive power design.
Solid-Phase Crystallization of a-Si:H by RTA
Authors: Jin Rui Min , Li Ding Zhen , Chen Lan Li , Han Xiang Ju , Lu Jing Xiao
Published: December 2010

Amorphous silicon films prepared by PECVD on glass substrate has been crystallized by rapid thermal annealing (RTA) at the same temperature for different time. From X-ray diffraction (XRD) and scanning electronic microscope (SEM), it is found that the grain size is biggest crystallized at 720°C for 8 min, an average grain size of 28nm or so is obtained. The thin film is smoothly and perfect structure.
Quantum State in Solid-Phase Crystallization of a-Si:H by FA
Authors: Jin Rui Min , Li Ding Zhen , Chen Lan Li , Han Xiang Ju , Lu Jing Xiao
Published: December 2010

Amorphous silicon films prepared by PECVD on glass substrate has been crystallized by conventional furnace annealing (FA) at different temperatures. From the Raman spectra and scanning electronic microscope (SEM), it is found that the thin film grain size present quantum states with annealing temperature.
Temper and Wear Resistance of Wide-Band Laser Cladded WC Coating
Authors: Kong Fan Zhi , Hu Xiao Dong , Yao Jian Hua , Lou Cheng Hua
Published: December 2010

High power continuous wave (CW) CO2 laser cladding was performed on H13 steel, pre-coated by superfine WC. After laser cladding, the materials were tempered for 6 hours. Scanning electronic microscopy (SEM) was used to observe the morphologies of the cladding layer. X-ray diffraction (XRD) was employed to analyze the microstructure of the cladding layer. The changes of microhardness, temper resistance and wear resistance were tested. The microhardness of cladding layer before tempering was 1.4 times of that of base metal and 1.9 times after tempering at 500°C. The wear resistance and tempering resistance were improved.
Optimal Design and Simulation of Active Vibration Isolation Platform Based on Fuzzy Control
Authors: Zhang Yi , Xia Min Min , Qin Jin Yi , Fang Zi Fan
Published: December 2010

In order to improve the isolation effect of ultra-precision vibration isolation platform, an approach of advancing structural parameters optimization for the system based on fuzzy control is presented. This paper created a platform parametric model In ADAMS / view; completed the structural optimization under circumstances of taking the acceleration of vibration isolation platform, the system dynamic deflection and the dynamic displacement of the base as performance objective function; and applied the method of co-simulation using ADAMS and MATLAB under fuzzy control. The simulation results show that the active vibration isolation system optimized by ADAMS could effectively enhance the effect of active vibration isolation platform; the method of co-simulation provided a new way for dynamics studies of vibration isolation system.
Study on Experiments of Nano-Abrasive Polishing in Hydrodynamic Suspension Liquid
Authors: Zhan Jian Ming , Mao Jian Hua , Liu Qi Tong
Published: December 2010

When nano-abrasives of high speed polish work-piece, they cut it and crush it and there are brittle fracture and surface distortion. For work-pieces of hard-brittle materials, there should be no surface distortion. Therefore, the efficiency of nano-abrasives polishing work-pieces of brittle materials should be much lower than that of metals. In this paper, work-pieces of Cr12MoV and glass K9 are polished by nano-abrasives driven by high speed hydrodynamic suspension fluid to study how it works. The experiments show that the efficiency of nano-abrasives polishing work-pieces of hard-brittle materials is much higher than that of metals.
Lifetime Distribution Model of Port Facilities with Pitting Corrosion of Stochastic Processes
Authors: Zhou Bing Hai , Zhai Zi Qing
Published: December 2010

Pitting corrosion damages seriously the structure strength of port facilities. To estimate the lifetime of port facilities, a new lifetime distribution model of port facilities with pitting corrosion of stochastic processes is proposed. Pitting corrosion can be considered as a combination of two physical processes: pit initiation process and pit growth process. The pit generation process is modeled as a non homogeneous Poisson process. The pit growth process is represented by a gamma process. A lifetime distribution model is derived based on the combined stochastic processes. Finally the proposed models are tested and simulated. The results indicate that the proposed model is feasible and valid for estimating the lifetime of port facilities.
Portability of WSN Sensor Driver Using Abstraction Layer and FSM
Authors: Yin Song , Huang Li Li , Zhao Hong , Wang Yang , Xia Ping
Published: December 2010

Portability is important in developing applications for Wireless Sensor Networks (WSN). The design for WSN sensor driver using of abstraction layer and FSM theory could achieve portability and improve WSN performance. The drivers of two different typical sensors were implemented, and according to FSM theory, the sensors state transition diagrams are depicted. We research the state transition in detail and summarize the interface. A key conclusion could be drawn that the operation of the sensors need the interface of Reset, Power Down, Start Read, etc. A UML generalization relationship could be created. On running time, the embedded programs access the driver implementation via universal virtual function interface, so that it could accommodate to various sensors.
Semantic-Based Optimal Deployment of Manufacturing Resources for Multi-Disciplinary Collaborative Manufacturing
Authors: Chu Chang Yong , Shen Guo Qiang
Published: December 2010

This paper focuses on multi-disciplinary resource configuration optimization problem of collaborative manufacturing in an open environment. First a semantic-based manufacturing resources retrieval and deployment framework is presented, then the four layers of the proposed framework, i.e. resource modeling, resource retrieval and annotation, resource discovery, and optimal resource deployment are discussed in detail.
Higher Eigenmodes Vibration Cantilever's Resonance Frequency and Cantilever Spring Constant
Authors: Huang Qiang Xian , Hou Qi
Published: December 2010

Based on dynamics theory, we have built several structures models close to the real cantilever of atomic force microscope. This paper deduces the higher eigenmodes vibration of single-layer camped-free cantilever in the resonant frequency calculation formula, extend to derive the equation of the resonant frequency for the cantilever with a mass M* on the moving end, introduce and extend the design theory of thin-walled "equivalent" concept, establish the bi-layer or multi-layer film structure of the equivalent model, use the single-layer camped-free cantilever method discussed in the resonant frequency of the multi-layer cantilever beam. Make full use of the higher eigenmodes vibration model, to discuss the ideal condition of cantilever spring constant.
Influence of Ice Covering on Stiffness of Tower Components
Authors: Dou Yi Cheng , Zhu Da Lin , Zhang Bing , Li Li Bo
Published: December 2010

In the icing electric transmission tower computation, has neglected the influence of ice stiffness and geometric effect to the iron tower component's stiffness. In the heavy ice area, such simplification is possibly inappropriate. Base on the parallel principle, proposed the ice-coated compression bar flexural stiffness formula, and proofed result correctness through finite element computation. Took the circular solid section and circular tuber section ice-coated tower components for example, ice-coated tower components were equivalent to compound materials in heavy ice area. Under certain load condition, compared the deflection and stiffness of tower component covered the different thickness ice, which took the line load with equivalent to the compound materials. Result showed that in the heavy ice area, the ice geometry effect has increased the tower component stiffness. The influence is more obvious to the tower stiffness than its dead-weight.
Risk Analysis of the Production Line Type Design Based on the Lean Production
Authors: Cai An Jiang , Yang Shun
Published: December 2010

Investigating the results from a lack of a systematic framework analysis approach during production line type design in practice, this paper puts forth a method in implementing a multi risk analysis framework in five categories based on Lean Production, and utilizes the workshop method of Concurrent Engineer to organize the relevant personnel to evaluate a given risk. The applicability of this approach is shown in the example of the production line of an accelerator pedal module. The method described can optimize the result of production line type design and realize a reduction in design time and lower the cost.
Residual Stress Simulation of Stud Welding in a Rectangular Steel Tubular Surface
Authors: Wang Lei , Zhang Qi Lin , Chen Lu
Published: December 2010

A thermal-mechanical coupled finite element model has been presented to predict residual and thermal stresses during different stages of stud welding. The finite study was carried out using three-dimensional models. To enhance the accuracy of the numerical solution material properties including physical, thermal and mechanical properties supposed to be temperature-dependent. After the temperature distributions as a result of welding were calculated, thermal and residual stress values obtained. Residual stresses are attributed to the elasto-plastic response of the object towards the transient thermal stresses generated by the welding. After all temperature values reach the room temperature, the residual stresses decrease to a small value.
Dynamic-Performance Research of Placement Machine
Authors: Xiao Yong Shan , Song Fu Min , Fang Qiang
Published: December 2010

The placement machine was simulated by multidisciplinary co-simulation method in various working conditions, and its dynamic accuracy was studied by simulation. According to the structure form of the placement machine, the virtual prototype for co-simulation was built. The impact of all sorts of parameters on the system dynamic accuracy was simulated including the stiffness and damping of the slider and the shaft coupling, the friction coefficient and the mass distribution etc. The result shows this method is able to predict the dynamic performance and the control margin of the whole machine, instruct the design optimization and the selection, and provide the good design thought and direction for the matching design of the machinery and controlling system.
Remote Path Tracing Research of Educational Mobile Robot
Authors: Ge Yan Hong , Li Wen Feng , Song Wei , Dong Wen Tao
Published: December 2010

Mobile robot is high emphasized in educational circles for its rich theoretical connotation, wide application prospect and multi-disciplinary technical characteristics. According to the present situation of limited resources of educational robot, the characteristics of educational robot are analyzed, and then the robot hardware and software platform is constructed, and also by using related technology, the remote monitor for mobile robot is researched in order to realize localization of remote teaching and remote experiment. Finally, the feasibility and effectiveness of the system is demonstrated by the experiment of path tracing.
Two Dynamic Propagation Problems of Symmetrical Mode III Crack
Authors: Lü Nian Chun , Cheng Yun Hong , Wang Yun Tao
Published: December 2010

By the approaches of the theory of complex functions, two dynamic propagation problems of symmetrical mode Ⅲ crack were researched. The problems considered can be very facilely changed into Riemann-Hilbert problem by means of self-similar functions, and the general representations of analytical solutions of the stress, the displacement and dynamic stress intensity factor under the conditions of moving variable loads Pt and Px2/t2 which were applied the edges of mode Ⅲ crack, respectively, were readily acquired.
An Adaptive Location Updates and Propagation Scheme for Mobile Sinks
Authors: Ma Shi Qiang , Qi Xiao Gang
Published: December 2010

Mobile sink can be used to balance energy consumption of sensor nodes in Wireless Sensor Networks (WSNs). Sink is required to inform sensors about its new location information whenever necessary. However, frequent location updates of mobile sink can lead to both rapid energy consumption of sensor nodes and increased collisions in wireless transmissions. We propose ALUPS (A New Solution with Adaptive Location Update and Propagation Scheme) for mobile sinks to resolve this problem. When a sink moves, it only needs to broadcast its location information within a local adaptive area other than among the entire network. The overhearing feature of wireless transmission is employed when the adaptive location information is transferred. Compared with LURP (Local update-based routing protocol in wireless sensor networks with mobile sinks) and SLPS (Simple Location Propagation Scheme for Mobile Sink in Wireless Sensor Networks), ALUPS performs better both in low energy consumption and success delivery ratio.
Development of Monitoring and Control System for Laser Remanufacturing
Authors: Hu Xiao Dong , Kong Fan Zhi , Yao Jian Hua
Published: December 2010

In order to monitor the process of laser remanufacturing and control the quality of remanufacturing, a monitoring and control system for laser remanufacturing was constructed with its hardware and software. The schedule of the system including signal condition, software interface, sampling and control method, was introduced. Infra-red thermometer with dynamic aiming device was designed to track the molten pool location. Photoelectric sensor was developed to measure the flow of powder. The contrast test results show that the fuzzy PID control system for powder feeding could achieve stable flow.
Research on Multi-Mode Driver Fatigue Detection System
Authors: Liu Zhen Yu , Wang Miao Miao
Published: December 2010

This paper presented a multi-mode fatigue detection system. It included visual detection, multi-point pressure detection and physiological signal detection. Visual detection mainly carried out on eyes and mouth feature extraction and the states detection. First, skin color detection was used into face image extraction,and then one-dimensional wavelet transform and gray integral projection were used to detect the eye and mouth in human face image. Finally, the status of the eyes and mouth were detected to judge fatigue. The principle of multi-point pressure detection was that during fatigue state period, the body and the back will be still in a long time. So we can use sensors to detect pressure points to judge fatigue. Physiological signal detection was detected by the speed of the human wrist pulse signal. The paper mainly presented visual detection that used the camera to capture face images. The algorithm has advantages of low computation complexity, high speed and better detection effect.
Study on Reliability Test Methods of Machining Center
Authors: Zhang Xiang Po , Yu Nai Hui , Shang Jian Zhong , Wang Zhuo
Published: December 2010

As the main subject of the reliability research, the reliability test is an important technological way to improve the reliability of the machining center (MC). Based on the failure characteristics and reliability research status of machining center, some related issues to the MC’s reliability test were studied in this paper. Three reliability test methods of MC, field test, laboratory test and virtual test were introduced, and the advantages and disadvantages were analyzed. It has some engineering significance as it provided a guideline to select a correct and effective method to the reliability test of MC.
An Abnormal IP Traffic Detection Model Based on Scale-Free Network
Authors: Li Jun , Niu Yan
Published: December 2010

A model of detecting an abnormal IP traffic in a subset of network is described. The model is based on the hypothesis that random sampling subnet are the same probability distribution as the entire network if some conditions are met with, nodes’s degree in IP traffic can be processed as a power-law distribution in scale-free network . The model analyzes the power exponent and relations between the anomalous behavior and parameter r. Finally, a test was conducted by the data, some type attacks could be identified exactly. the model provides a new framework for intrusion-detection system.
Cutting Force Induced Error Prediction and Compensation Based on Feed Servo Motor Current
Authors: Wang Bao Sheng , Hao Hong Yan
Published: December 2010

According to the relation between feed servo motor current and cutting force, online monitoring of cutting force is realized by measuring the motor current. For the delay of current signal to cutting force, a method with artificial neural network is proposed. Subtracting the geometric error from the total error which is measured with a laser interferometer within the working volume, the cutting force induced error is achieved. With the multi-body system theory and the back-propagation neural network, cutting force induced deflection prediction model is established, and an error compensation system is developed. Milling experiments are done to validate the prediction model and the system. The results show that force error is reduced markedly, and the method for prediction and compensation is of great important to precision manufacturing.
The Model and Simulation of the Potato Harvester
Authors: Zhang Fu , Qiu Zhao Mei , Mao Peng Jun , Xu Rui Liang , Jun Wang
Published: December 2010

The model of potato harvester was established by Solidworks software aiming to resolve the problems of low design efficiency and backwards design methods. The potatoes harvester included the chassis, the depth wheel, the dithering and elevating device, the digger blade, the universal joint, the suspension bracket, the gearbox, the tilting ring mechanism, the riddler, and so on. The virtual assembly and the simulation of potato harvester were researched by Solidworks software, and the motion and the assembly had not existed interference phenomenon when the model run the static and dynamic interference inspection. The results showed that the assembly and design of potato harvester will improve the design quality and efficiency and reduce the design cycle, and the research on the motion simulation of potato harvester will provide theoretical foundation for development and application of potato harvester.
Grouping Rank Product Meta-Analysis Method for Identifying Differentially Expressed Genes in Microarray Experiments
Authors: Tian Yuan , Liu Gui Xia , Zhou Chun Guang
Published: December 2010

One of the main purposes in analysis of microarray experiments is to identify differentially expressed genes under two experimental conditions. The Meta-analysis method, rank product meta-analysis approach, considered a powerful tool for identification of differentially expressed genes. However, rank product meta-analysis approach used the each dataset in the computation of the fold changes, which leaded to less computational efficiency. Here we modified the rank product meta-analysis approach to obtain an improved model for identifying different gene expression. The new model, grouping rank product approach, adds competitive classification of samples to group datasets before the computation of the fold changes. We used the grouping rank product approach on two simulated datasets and two breast datasets and showed that the grouping rank product approach is not only as accurate as the rank product meta-analysis approach, but also more computational efficient in identifying differentially expressed genes.
Product Color Intelligent Planning Method Based on Multi-Emotion
Authors: Ding Man , Sun Wei , Zhang Xu
Published: December 2010

In this paper, a product color planning method based on multi-emotion was proposed. This method can generate the optimal product color-combination schemes which satisfy user’s multiple image requirements. A mathematical model was developed to generate product color-combination schemes which most closely meet the required images. Then Difference Evolution (DE) was employed to search for the optimal color-combination schemes. The application on a two-colored sofa was provided to demonstrate the effectiveness of the product color planning method based on multi-emotion, which meets the desired result using this method proposed.
Research of System of Trailer Axle’s Function Test
Authors: Wu Wei Bin , Hong Tian Sheng , Chen Xu Xiang , Yang Shi Ting , Chen Kai Cheng
Published: December 2010

Axle is one of the most important parts related to the safety of trailer’s operation on the railroad. In China, the checking of axles is mainly through visual inspection and hammer examinations. The construction of an automation hardware system was simulated by Pro/E, including support, guide rail, sensor, AC servomotor and servo driver conformed to the model. Next, for controlling the operation of the entire system, LabVIEW was used to write a program and to control the rotation of servomotor. The pressure heads controlled by linkage system were utilized to load the axle; meanwhile, through the PCI of NI, the data of pressure and displacement was collected. After calibration, the relative error of pinpointing sensor was 5.207%, and the average relative error was about 1.4%. Analyzed by SPSS, the voltage-load formula's correlation coefficient R is greater than 0.994, while the significance is less than 0.05, showing the regression of great significance. Finally, the capabilities of the simulated axle, such as fatigue, stiffness, intensity and stress, were analyzed carefully.
Research of Analysis System for Citrus LAI Spectrum Data
Authors: Wu Wei Bin , Hong Tian Sheng , Guo Jin Xing , Li Dong Dong , Mai Zhi Lin
Published: December 2010

The method to provide crop biomass status information for precision agriculture by researching the features of leaf area index(LAI) is presented in this paper. The relationship between LAI and spectrum can be identified by spectrum analysis, thereby achieving fast and accurate LAI measurement. The exact total leaf area and the nominal LAI values of citrus leaves can be calculated through a scanning calibration experiment. Analysis system for citrus LAI spectrum data is made up of a data acquisition platform with FieldSpec-FR and computers as its key components to collect spectrum data of leaves and an inversion platform with computers, ViewSpecPro, SPSS and other softwares as its core to calculate the LAI of citrus leaves. The fitting equation of LAI and spectrum information obtained is Y=1.5106X+0.7869 and the calculation error is ±0.0378%. The fitting equation of LAI and dry weight obtained is Y=0.0924X+3.1252 and the calculation error is ±0.3002%. The fitting equation of dry weight and wet weight obtained is Y=0.1807X-0.1133 and the maximum calculation error is 2.2713%.
Numerical Simulation Investigation on the Temperature Field Distribution and Variations in Hot Stamping Process
Authors: Zhang Lei , Zhao Guo Qun , Li Hui Ping
Published: December 2010

With finite element software Abaqus, a coupled thermal mechanical simulation of hot stamping process of U-Channel part using high strength steel was performed. Through the analysis of the temperature field distribution on the die surface, the influence of contact state between die and blank on the temperature field distribution was discussed. With temperature history curve of a selected node on die corner, the heat flow on two contact boundaries (die surface and cooling water channel surface) was discussed and its effects rules on the die temperature were given.
An Improved CAL Register File with Dual-Threshold Technique for Leakage Reduction
Authors: Hu Jian Ping , Zhu Jia Guo
Published: December 2010

Scaling down sizes of MOS transistors has resulted in dramatic increase of leakage currents. The leakage dissipation caused by leakage currents is becoming an increasingly important fraction of the total power dissipation in nanometer integrated circuits. To decrease leakage power dissipations is becoming more and more important in micro-power nanometer circuits. An improved CAL register file using DTCMOS (Dual-Threshold Technique) for reducing leakage dissipations in active mode is addressed in this paper. The BSIM4 model is adopted to reflect the characteristics of the leakage currents. All circuits are simulated using HSPICE at 45nm CMOS process. Simulation results show that the register file with dual-threshold can reduce about 15.6% power dissipations.
Analysis and Design of Drive Closed-Loop for MEMS Vibratory Gyroscope
Authors: Yang Liang , Su Yan , Qiu An Ping , Shi Qin , Zhu Xin Hua , Feng Rui
Published: December 2010

The principle of drive closed-loop for tuning fork comb MEMS vibratory gyroscope is analyzed. The core of the closed-loop is to keep the vibration speed stable by adding driving force offset the damping force. The closed-loop with a single Automatic Gain Control (AGC) loop is chosen to maintain the vibration speed stable, and then the closed-loop with AGC is analyzed to obtain its transfer function. The transfer function simplifies the nonlinear AGC system to a linear system which is easy analyzed its parameters impacting the system. The values of two important parameters of AGC were chosen via simulation. The whole closed-loop system was simulated in SIMULINK. The circuit is built and tested in accordance with the theory of analysis and simulation. Experimental results demonstrate that the stability of the amplitude of vibration speed is 90ppm; and that of the frequency of vibration speed is 114ppm.
Your Bearing Fault Diagnosis Based on Bispectrum and Bispectrum Entropy Feature
Authors: Huang Jin Ying , Pan Hong Xia , Bi Shi Hua
Published: December 2010

Fault feature extraction and application is the key technology of fault diagnosis. In this paper, a fault diagnosis method using bispectrum and bispectrum entropy as the fault feature parameters is put forward. Bispectrum entropy as the information entropy in bispectrum domain can reflect the complexity of information energy. When the structure is failed, the distribution of bispectrum will be changed. bispectrum entropy can reflect this change and achieve good separation of the different types of fault. Vibration signal in different bearing states of a secondary drive gearbox is compared and analyzed, bispectrum energy spetrum and bispectrum entropy are extracted. Feature vector is set up via bispectrum entropy for the fault pattern recognition and diagnosis by BP neural network. The analysis result proves that bispectrum entropy is more sensitive to fault characteristic and can separate the fault of bearing.
Transverse Shearing Strain Energy Calculation of Single Cell Box Girder
Authors: Zhao Jia Jian , Wei De Min
Published: December 2010

Both the increasingly-thin walls of box girder cross-sections and the super-loads from trains or track vehicles make the behavior research on diaphragms and side walls become particularly important. According to the deformation of single cell box girder cross-section, the displacement parameters were designed, and the displacement modes of cross-section distortion angles were deduced. The schematic plans of diaphragms and side walls were simulated by rigid frames or plates. Both the shearing strain energy and the shearing stiffness of diaphragms and side walls were deduced on the basis of the principles of mechanics and finite element. The results show that the shearing strain energy increases with the displacement by a power function. And the method calculation results are close to the commercial FE software calculation results, which show that the calculation method of single cell box girder presented in this paper is correct and reliable. The calculation method is simpler than the commercial FE software calculation method. In the calculation method, whether diaphragms and side walls are calculated separately or calculated as some parts of the box girder or the vehicle - bridge system, the calculation precision of diaphragms and side walls remains unchanged.
The Experimental Study of Early-Age Strength and Elastic Modulus of Concrete
Authors: Zhang Deng Xiang , Yang Wei Jun
Published: December 2010

Based on large numbers of experiment results, this paper carries out statistical analysis and proposes the probability distribution properties of the random process of strength and elastic modulus and their coefficient of variation, and develops a new prediction model of early-age strength and elastic modulus and their coefficient of variation respectively. The model can provide good prediction of the development of mechanical properties of concrete structures in aging, and it is important to evaluate the concrete structure safety and reliability in the construction period.
Research on Temperature Stress of Large-Area Concrete Beam-Slab Structure
Authors: Zhang Yong Sheng , Li Yan Ying
Published: December 2010

Large-Area Concrete beam-slab Structure mainly means the monolithically cast concrete structure whose length and width are more than the maximum of the structure in the code. The influence of temperature change, shrinkage and creep on structure is the key to solving the problem. Through a practical engineering, Shrinkage and creep formulas accord with test results are brought forward. The calculation results of shrinkage strain, temperature strain and prestressed strain coincide test results and can be directed to the projects.
Mechanical Behavior Analysis of the Unbonded Prestressed Concrete Slabs with Openings Strengthened by Different Methods
Authors: Cao Xia , Jin Ling Zhi , Fu Qiang , Zhou Hong Mei , Liu Ya Qiong , Lan Li Jiang
Published: December 2010

Based on the contrast experiments of unbonded prestressed concrete slabs with openings subjected to uniform load strengthened by different methods, this paper investigates and analyzes the appearance and the development of cracks, deflections, bearing capacity of the unbonded prestressed concrete slabs that are with strengthening steel and with hidden beams. According to the experimental failure mode of the slabs, prestressed concrete slabs with openings by yield line theory considering the conditions to enhance the contribution of hidden beam and the strengthening steel. Compared with the experimental data, this paper puts forward some bearing capacity lift-off effect of the slabs under different strengthened methods.
Effect of Specimen Shape and Size on Compressive Strength of Concrete
Authors: Che Yi , Ban Sheng Long , Cui Jian Yu , Chen Geng , Song Yu Pu
Published: December 2010

The purpose of this study is to investigate the influence of specimen size and shape on compressive strength of concrete. Concrete cubes, cylinders and prisms with their size ranging from 150mm to 450mm were tested in unaxial compression. Failure patterns and the effect of specimen shape and size on compressive strength of concrete were investigated. In addition, theoretical size effect models, such as the MSEL and MFSL were used to analyze the size effect of concrete strength. It is shown that for specimens tested in this study, the two models are both applicable to predicting the compressive strength of specimens in various sizes with a reasonably good accuracy.
Verification of Adjustment Method of Design Seismic Shear Force of the Frame in RC Frame-Shear Wall Structure
Authors: Han Jun , Li Ying Min , Chen Wei Xian , Jiang Wei , Zhao Wei
Published: December 2010

Reinforced concrete frame-shear wall structure is a double resistance to lateral force system, in which the frames and shear walls work cooperatively and the distributive rule of the earthquake force varies with different earthquake actions. To ensure the frames bear the increasing earthquake shear force and play a role of second defense line due to the internal force re-distribution after the stiffness degradation of shear walls, the elastic design earthquake shear force of the frames should be adjusted. However the adjustment measures applied in Chinese code are proposed according to the design experiences of engineers and lack of the theoretical and computational analytical basis. Moreover, there is a dispute about ignoring the rule of the shear force redistribution along storey or not, it is necessary to further evaluate the rationality of the measures in the code. In this paper, based on a 3-D precise nonlinear frame-shear wall structure analysis model, the re-distributive rule of the internal force under strong earthquake was studied and the adjustment measures of earthquake force in the frames were checked. Finally, some design suggestions were proposed.
Experimental Study on Seismic Performance of SRC-RC Transfer Columns and Extension Length of Shape Steel
Authors: Wu Kai , Xue Jian Yang , Zhao Hong Tie
Published: December 2010

Experimental study has been carried out on the seismic performance of SRC-RC transfer columns. The effect of extension length of shape steel has been analyzed. Degeneration of bearing capacity becomes much more obvious when extension length of shape steel increases and failure patterns change from shear failure to bond failure. Displacement ductility changes with increase of the extension length of shape steel, enhancing at first and then reducing, reaching peak value when extension length of shape steel gets close to three-fifths of column height. But extension length of shape steel has little effect on the bearing capacity of transfer column. Although double stirrups are arranged at the location of shape steel discontinuous, strain of stirrup at this position is still much higher than anywhere else.
Nonlinear Static Analysis of Staggered Truss Steel-Timber Combined Structure
Authors: Qu Qin , Zheng Xiao Yan , Chen Xiang Tao
Published: December 2010

This paper, combined the characteristics of steel structure and timber structure, conceives a new system of residential structures—staggered truss steel-timber combined structure, carries out structural arrangement and optimization design on a six-layer residence, and makes a study on its seismic performance under rare earthquake. The author uses commercial structural analysis softwareto establish a basic model, conducts pushover analysis, draws the load-displacement curve, then getsthe capacity spectrum of the model, next compares with the demand spectrum under 8 degrees (0.3g)rare earthquake, finally gets the performance point of the structure. The results show that the inter-story displacement angles can meet the limit of seismic code. Meanwhile auther analyzes the distribution and the appearance sequence of plastic hinges, plastic hinges mainly occur in the truss webs, the chords and the frame beams in succession, and the number of plastic hinges is more. Bottom columns finally appear plastic hinges. These phenomena meet the design requirement—strong column-weak beam.Finally this paper gets a conclusion that staggered truss steel-timber combined structure shows good seismic capacity.
An Effective Way to Validate Signal Arrival Time in AE Structural Monitoring
Authors: Xu Jie
Published: December 2010

A practical method, based on the Akaike Information Criterion (AIC), is used to detect automatically the first P-wave arrival times during Acoustic Emissions (AE) monitoring. This method is used to increase the accuracy of detection procedure and to reject the data errors automatically. Two parameters, the quantification of the degree of certainty and the apparent velocity between observation sensors, were proposed to check the validity of AE events and to neglect errors. Both the original AIC-picker and improved AIC-picker algorithms are applied to AE signal processing. It can be shown that the improved AIC-picker is a reliable tool for automatic onset detection of AE signals.
A Metamodel Based Damage Identification Method
Authors: Fang Sheng En , Perera Ricardo
Published: December 2010

A metamodel can be represented by the forms of mathematical equations (response surface models) or neural networks (black-box models) in the interest of correlating the inputs (parameters) with the outputs (responses) of a physical system. In view of little relevant research, this paper attempts to use response surface models as surrogates for FE models due to the provision of explicit equations and easy implementation in the aspect of modeling updating. Metamodeling is achieved by using the design of experiment involving the 2k factorial design and the central composite design for parameter screening and structural input-response modeling respectively. The feasibility of the proposed method has been demonstrated using a numerical beam example which proves the satisfactory performance of employing such metamodels in model updating based damage identification.
Elastic Waves in Pipe Resting on Two-Parameter Foundation
Authors: Lin Zhi Rong , Kasai Akira
Published: December 2010

A method based on Hamiltonian system in complex field is presented in curvilinear coordinates to study elastic waves in pipes of various shapes on two-parameter foundation. The method and its computer program are verified and applied to analyze the axial wave propagation problem of elliptical pipe embedded in foundation. Numerical results show the dispersion changes of varying degree in the presence of foundation and reveal significant influences of the second foundation parameter especially in the low frequency range. The promising and effective way of controlling propagating waves by adjusting the shear ability of foundation is also indicated in the results.
Study on the Damage Detection of RC Frame Beams Based on the Vibration Mode Slope Change Rate
Authors: Xue Gang , Li Feng Ge
Published: December 2010

Based on the mechanism of the relative change rate of mode shape (RD), a new damage identification quantity called the vibration mode slope change rate (RD’) is proposed. The new quantity is analyzed with the fundamental principles of function differential method. Dynamic test is carried on 5 RC frame beams, which are subjected to an increasing static load in the middle to introduce cracks. After each load step, unloading, and an experimental dynamic monitoring is performed on the beam, then reloading to the next step. Modal analysis is carried out on frame beams under each load step, and modal displacements are given, the vibration mode slope change rate graphs of the RC beams are calculated, which can be used to detect multiple-damages. By means of SAP2000, the comparison analyses between RD and RD’ indicate that RD’ can effectively avoid the careless judges and misjudge in the damage identification of frame beams.
Reliability Analysis of Hydraulic Tunnel Lining Structure with Stochastic Finite Elements Method
Authors: Liu Dong Hai , Zheng Jiang , Li Zi Long
Published: December 2010

Many uncertain factors, e.g. surrounding rock physical and mechanical characteristics, are important influence effecting on lining structure safety. By comprehensively considering uncertainties of surrounding rock conditions (lining structure and initial stress), we put forward a new method used to quantitative analysis on the lining structure safety. Analyzing the uncertainties and their distribution characteristics of hydraulic tunnels, we adopted stochastic finite elements method to calculate failure probability of lining structures corresponding to various geological conditions, and then the reliability and sensitivity were achieved. Applying the presented method to a practical project, we got the failure probability of the tunnel lining structure under the construction condition, which provided great support for structure optimal design and tunnel construction safety protection.
The Effect of Freeze-Thaw Cycles on Mechanical Properties of Concrete
Authors: Song Wa Li , Li Xue Fang , Ma Ke Fei
Published: December 2010

Freeze-thaw cycles have the impact on mechanical properties of the concrete in northern areas of China. In this paper, on the basis of the damage degree of freeze-thaw cycles and experiment data, for C30~ C50 concrete after freeze-thaw cycles, the loss rate of relative dynamic elastic modulus and the relation between compressive stress-strain are analyzed. Compounding good frost resistance of concrete is one of important measures to improve durability of concrete, and degradation patterns of mechanical properties are found. This study may serve as prediction of the service life of concrete in cold regions.