bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the Two-Phase Operation Mechanism of Three-Phase Motors Based on LC Phase Shifting Method
Authors: Zheng Zai Ping , Huang Yu Ping , Zhong Yue , Wu Hong Xing
Published: March 2015

In the absence of three-phase power supply, it has certain practical significance to connect the three-phase induction motor to the single-phase power supply for single phase operation. This paper analyzes the asymmetric circuit system of the motor by the method of symmetrical components-Lc phase shifting, disassembles the voltage and current of the three-phase motor stator winding into three groups of symmetrical components: positive sequence, negative sequence and zero sequence. We derivate and analysis the LC phase shifting method to simulate and validate the Lc phase shifting method theory, deduce the formula for calculating of optimum external capacitance and inductance, simulate and calculate all kinds of single phase operation method, finally we use the simulation software to simulate and validate three-phase induction motors single phase operation.
Multivariable Decoupling Control Based on TC Control in the Diving and Floating Process of AUV
Authors: Jiang Zhi Bin , Liu Tie Jun , Xu Hui Xi , Jia Song Li , Cui Jian
Published: March 2015

The diving plane motion of autonomous underwater vehicles (AUVs) is a complex multivariable nonlinear system with pitch-heave coupling. Tornambe’s controllers (TCs) can online estimate the dynamic uncertainty regardless of the type of disturbance. The TCs for depth and pitch angle are adopted to achieve multivariable decoupling control by introducing virtual control inputs. The methodology can obtain fast and non-overshoot control of depth and pitch angle in the diving and floating process. Simulation results demonstrated the effectiveness of the proposed control scheme.
Single Stand Reversing Mill Steel Belt Running Deviation System Analysis and Simulation
Authors: Duan Heng , Wu Zhang Yong
Published: March 2015

This paper mainly analyzes the single stand reversible rolling mill strip wandering mathematical model of electro-hydraulic servo system using MATLAB/Simulink and constructs electro hydraulic servo control system model. It carries on the simulation analysis of the quality of the electro-hydraulic servo system. Through the study of strip running deviation design of servo system , we understand of the principle of design of electro-hydraulic servo hydraulic system and the MATLAB simulation.
A Variable Universe Self-Tuning Fuzzy-PI Speed Controller for Induction Motor with DTC-SVM
Authors: Yu Hong Xia , Chen Zhi Cheng
Published: March 2015

In the paper, To control the speed of induction motor drive with DTC-SVM, A variable universe self-tuning fuzzy-PI(VUFPI) controller was designed based on the concept of variable universe to generate the torque reference value, Two inputs of the fuzzy controller are speed error and error change rate, the output of the fuzzy controller are adjustment parameters (,) of PI controller parameters (Kp, Ki), the input and output variable universe of fuzzy controller were regulated by scale factor which is calculated according to error grade, The simulation results show that the proposed method has fast response speed and lower torque ripple.
Research and Design of Large Equipment Electromagnetic Compatibility System
Authors: Tang Ji Ling , Li Nian Feng , Liu Hong Liang
Published: March 2015

Through the study of vehicle work mechanism of the large electronics devices，In view of the interference between vehicles and between different equipment of the same car ，the mathematical model of EMC system of the transmitters and receivers are established the.and applied to on-board equipment. The experimental results show that the system can effectively restrain interference signals of on-board equipment，ensuring the reliable operation of vehicle equipment.
3D Printing Technology Enhances Small Enterprises Improvement Opportunities
Authors: Liu Ling , Yang Yi
Published: March 2015

This thesis, based on the characteristics and advantage of 3D printing technology, discusses the opportunities and challenges for the development of small enterprises, using new economic growth point of digital manufacture to promote employment.
A Reliability Analysis of NC Machine Tools Based on the Weibull Distribution
Authors: Li Hui Liang
Published: March 2015

In this paper, a series of numerical control machine tool truncated failure data collect.The data are assumed to be two parameter weibull distribution and related parameters is obtained and relevant inspection and test of hypothesis, it is concluded that the mathematical model of batch of nc machine tool failure interval time distribution.Relevant indicators to determine the reliability of nc machine tools, machine tool's observations, Machine tool observations, point estimation and interval estimation index value provide a theoretical basis for the research on reliability of machine tool.
Research on MES of Iron District Based on the Short Process of Iron-Steel Interface
Authors: Luo Rong , Wang Chen , Ren Hong Bo , Zhang Kai Bi
Published: March 2015

Steel industry is an important part of the national economy, however, the complex process of ironmaking-steelmaking has been a serious constraint to the development of steel enterprises. In this paper, on the basis of the traditional processes of iron-steel interface, the planning of short process of iron-steel interface with “One open ladle” is proposed. There is also the design of MES in iron district, which has been applied in a steel enterprise of Chongqing, China, with significant effects.
The Variable Cross-Section Rotary Dynamic Seal and its Application
Authors: Zou Long Qing , Yuan Xiao Jing , Chen Xue Xin
Published: March 2015

This paper mainly introduces the variable cross-section rotary dynamic seal, sealing mechanism, research and development, listing examples of variable cross-section rotary dynamic seal applied in the petroleum machinery. Due to its simple structure, reliable sealing performance, it is widely applied to the occasions such as high pressure, in suffering much, shock vibration.
Design and Simulation of New Tooth Profile of Flexspline for Harmonic Gear Drive
Authors: Zu Li , Feng Lan Lan , Sun Yan Yang
Published: March 2015

We focused on the parametric design and simulation of new tooth profile “circular arc-involute-circular arc” for flexspline in this paper. Based on the MATLAB software, the basic tooth profile of hob was designed. According to gear generating cutting principle, the simulation of processing for flexspline tooth profile has been realized. By tooth profile normal method, we calculated flexspline tooth profile which is conjugated with the basic tooth profile of the cutting tool, and gave the contrastive studies on process simulation and theoretical calculation. Results show that they are feasible in solving the new tooth profile of flexspline. When changing the key structure parameters, the different changing regulations of flexspline tooth profile can be gained. The research results are meaningful to improve the capacity of harmonic gear drive.
Application of Image-Pro Plus in the Groove Filter Rod Characteristic Parameters Measurement
Authors: Zhao Liang , Liu Wan Li , Ying Wei
Published: March 2015

Basing on the Image-Pro plus (IPP) technique, a kind of groove filter rod characteristic parameters (such as groove depth, channel ventilation area, number of grooves) measurement system was build. Method: put 5 groups of standard channel ventilation area-known groove rods and 10 pre-cut self-made groove filters under the microscope with the groove sides up, adjust the intensity of the light and the focal length, take the pictures of all. Use IPP to measure all the parameters, and MINTAB to analyze the accuracy and precision of the IPP system. Results: (1) the IPP system is convenient to operate, easy to use and fast to measure the characteristic parameters such as channel ventilation areas, groove depth as well as groove numbers of the groove filters. (2) the measurements for the channel ventilation area, groove depth doesn't exist linear bias. The channel ventilation area precision index GageR&R = 24.66 < 30, and groove depth precision index GageR&R = 26.40 < 30, which means measurement precision is good.( 3)The manual measurement mode and automatic measurement mode of IPP system in regard to the measurement results bear no significant difference (P > 0.05), and can be chosen for different needs. The measuring method provides help in the research of groove filters rod’ tar-reducing mechanism as well as in the increase of production process control capacity.
Satisfaction Track Extraction Model Based on Threshold Detection
Authors: Bin Huang Deng , Zhi Xia Xue
Published: March 2015

For multi-target radar track Extraction, the paper proposed a multi-regional threshold method, by setting a plurality of parameters threshold, to determine whether the next time point falls within the threshold based on relevant criteria, then to build the track; further proposed satisfaction law, track was established by the relevant observation points, which the satisfaction function is defined between the associated trace points and set it to the threshold, Through the case of simulation, the model results are given in comparison.
The Analysis of the Testing Accuracy of the Anti-Force Rolling Brake Testing Platform
Authors: Zhu Xiao Wei , Zuo Fu Shan , Xu Ying , Shi Xiao Kang
Published: March 2015

Many Factors influencing the testing accuracy are discussed according to the differences between the testing data of most of the domestic anti-force rolling brake testing platform. We try to get the theoretical analysis and be proved by experiment through the mechanical model. We focus on some respects just as attachment coefficient, tire pressure, vehicle moving and direction displacement which influencing the testing accuracy of the anti-force rolling brake testing platform.
The Research of Intelligent Mining Subsidence Prediction System
Authors: Tian Jin Zhou , Zhu Kun
Published: March 2015

This article introduces, by the application of equivalent conversion of line integral of probability integral method theoretical model, the research of the system architecture, main function and key technology of the intelligent mining subsidence prediction system which includes mining subsidence prediction and surface movement station parameters obtainment and can directly connect with the AutoCAD which is generally applied in mining area. Combined with specific engineering, this article introduces the actual application condition of this system to guide the safety production of coal mine and to assist engineering designers to work on the mining subsidence prediction better.
Design of Data Acquisition System Based on Ethernet and Virtual Instrument Technology
Authors: Han Liang , Li Yan Song
Published: March 2015

Ethernet based on TCP/IP is a standard open network, which promotes the development of data acquisition in the direction of network. Data acquisition and processing systems connected by Ethernet make the data acquisition terminals (lower computer) and processing control center (upper computer) from integrated to discrete. Separate data acquisition terminals can realize miniaturization and modularization and increase the flexibility of the application. A new type, low cost, high precision data acquisition terminal based on ARM processor was designed for solving the problem of complicated structure, big volume and high cost of traditional data acquisition system. Combined with the technologies of network communication, a data acquisition PC system based on virtual instrument technology was designed by LabVIEW.
One Operational Visual Method for Oil Spill Detection by SAR Image
Authors: Chen Peng , Fan Kai Guo , Gu Yan Zhen , Xu Ke
Published: March 2015

SAR has been proven to be a useful tool for ocean oil spill detection due to its large coverage, independence of the day and night cycle and all-weather capability. In this paper, one operational visual method for oil spill detection using SAR image was performed and the oil spill key information, such as the location and coverage, has also been demonstrated. The results show that the operational visual method of oil spill detection by SAR image will play an important role in the marine environment protection.
A New Rapid Detection of the Temperature Coefficient System
Authors: Li Xue Yi , Chen Xian Yan , Xiao Fen , Liu Na , Liu Qing Huo
Published: March 2015

The temperature coefficient of the microwave dielectric ceramic materials is one of the important dielectric property parameters. A new method, which can detect the temperature coefficient of microwave dielectric ceramic material, is presented in this article. The test method and software buildup of the system are also introduced. The new system has the advantage in obtaining fast, reliable and high accuracy measurement performance.
Multiplexed Voltage Measurement for Serial Connected Power Li-Ion Battery String
Authors: Liu Lin Yang , Shen Han Xin , Zhu Wen Zhang
Published: March 2015

This paper proposes a new method of multiplexed voltage measurement for serial connected power lithium battery string. The method has some advantages such as simple circuit, the simultaneous measurement and high accuracy. The principle of the voltage measurement circuit is analyzed in this paper, and proposes the solution to the factors affecting the measurement precision of the circuit. Experiments show that this circuit leakage current and temperature drift is small, and also have high precision.
Firefly-Inspired Synchronicity with a Weighted Factor for Wireless Sensor Networks
Authors: Zhao Hai Lei , Song Ping , Hao Chuang Bo
Published: March 2015

Firefly-inspired synchronicity method using reackback response is effective with existence of message delay. We introduce a weighted factor based on RSSI into the phase increment calculation. Besides, different coupling strength parameters are selected according to the degree of synchronicity to achieve a good balance between synchronicity speed and accuracy. Simulink module is constructed and the results prove that this method shows great resistance against random variation of the message delay within an acceptable range.
Translation Compensation Based on Cycle Subtracting of Micro-Doppler Curve
Authors: Zhang Dong , Feng Cun Qian , Zhang Yong Shun , Li Jing Qing
Published: March 2015

To solve the problem of translation compensation on ballistic target under complex scattering model in midcourse, a novel rule based on cycle subtracting of micro-Doppler curve is proposed. Firstly, the period is estimated by the period feature extraction algorithm which is based on the correlation of range profile envelopes. Then, extract the Doppler curve of the strongest scattering point through the Viterbi algorithm. Lastly, do the cycle subtracting and single cycle integral to the curve, the precious translation parameters can be got by the least squares estimating. This method is not only suitable for the rotating model, but also valuable for the precession model and the sliding model. The effectiveness of the proposed rule is verified by simulation results.
An Improved Method for Power Harmonic Analysis Based on Blackman Window and Phase Difference Correction
Authors: Xia Wei Jian , Jiang Yun Shuang , Cai Jia Jia
Published: March 2015

It is difficult to make the realization of synchronous sampling and the whole cycle truncation when we use the fast Fourier transform (FFT) for power system harmonic analysis .Once the FFT is used, the spectral leakage caused by it will affect the accuracy. Using Blackman window weighted to the harmonic signal, combined with the spectrum analysis of phase, An improved method for power harmonic analysis based on Blackman window and phase shifted difference correction is presented in this paper. The calculation equation of multiple fundamental harmonic signal frequency, amplitude and initial phase angle is derived and the conventional spectral phase correction method is improved. The simulation results show that the calculation accuracy using Blackman window phase correction signal harmonic analysis is improved significantly compared to Hanning window interpolation, Blackman window interpolation and Hanning window phase difference. The algorithm is simple, and has high precision and versatility, which can be applied to high-precision power metering and power quality analysis.
Analysis of Nuclear Power Plant Transient Recognition Method Validation Utility Strategy
Authors: Li Yu Wen , Liang Ji Xing , Ding Qing Qing
Published: March 2015

Compare and analysis the transient identification in Nuclear Power Plant fault diagnosis method. According to how does these methods for nuclear power plant systems HTR effect, Further proposed to a problem that towards existing transient recognition of methods to verification effectiveness. Preliminary analysis of the three kinds of validation strategy, after a comparative demonstration, it is formed the preliminary research on the utility analysis framework. Utility to verify the framework for the Nuclear Power Plant fault diagnosis methods carry out intensive research provides a theoretical basis.
Application of an Improved Colored Petri Net Modeling Method in Certain Missile Training System
Authors: Wang Chun Jian , Yue Wei , Ji Hai Yan
Published: March 2015

In allusion to the need of analyzing complex system, we have proposed a method named multi-grade color Petri net. We for the first time use this new method to analyze a missile training simulator system. This model can accurately reflect the complex environments of the system and avoid the difficulty occurring often in developing accurate mathematics model by using classical research approach.
Bistatic Polar Format Algorithm Based on Wavenumber Vector
Authors: Qi Chun Dong , Shi Shan Wei , Peng Kai Nan , Huang Han Yue , Xu Jia Chen , Kong De Chuang
Published: March 2015

The paper concentrates on bistatic polar format algorithm (PFA) for focusing the spotlight bistatic Synthetic aperture radar (SAR) data. Exploring the imaging geometry of spotlight mode, a wavenumber vector Kbis derived according to the original definition of wavenumber. The direction of the vector Kb corresponds to the path from the transmitter to the target in the scene to the receiver in the bistatic SAR configuration. Using the vector Kb, a point target position vector in the scene can be expressed as the same form as that of conventional monostatic spotlight SAR. Based on the vector Kb, the spotlight bistatic PFA is derived and is presented concisely. In the simulation experiments, the presented PFA and BP algorithm process the same area target respectively. The result of the experiments show the PFA mentioned in this paper is valid. The quality of the processing result achieved by the PFA is not worse than that by BP algorithm.
Optimization of Multi-Objective Coverage Strategy Based on Multiple Particle Swarm Coevolutionary Algorithm for Water Environment Monitoring System
Authors: Zhao Hong Wei , Tian Li Wei
Published: March 2015

This paper built a multi-objective optimization model and proposed an improved multi-objective particle swarm optimization algorithm called MPS2O ,which is based on Multiple Particle Swarm Co-evolutionary. The MPS2O algorithm has considerable potential for solving multi-objective optimization problems. Mathematical benchmark functions also shows that the proposed algorithm is an excellent Alternative for solving multi-objective optimization problems. Making full use of the research findings home and abroad, MPS2O has been chosen to be the coverage optimization strategy of the wireless sensor networks in Water Environment Monitoring System. Simulation results demonstrate that the MPS2O algorithm is more efficient than the PSO algorithm in solving this real-world problem.
Yarn Quality Prediction and Process Parameters Optimization Based on Genetic Algorithm and Neural Network
Authors: Yang Jian Guo , Xu Lan , Lu Zhi Jun , Xiang Qian , Liu Bin
Published: March 2015

Quality prediction is an important means of the quality management in modern spinning production. This paper proposed a yarn quality prediction model based on Genetic Algorithm and back propagation neural network to predict the yarn quality and optimize the process parameters. The main identification model parameters were optimized by using genetic algorithm, and the prediction performance of the model has been compared against that of the BP neural network model. The effectiveness and availability of the proposed model are verified with the use of actual production data.
Application of Fuzzy Mathematics Model in Evaluating Order Priority
Authors: Ma Fei , Gu Hong , Xu Wei Hua , Tao Qin Qin
Published: March 2015

The method of make-to-order has gradually become the primary mode of production. It is an extremely important ability for enterprises to make production scheduling and response to the changes of customer demand agiely. Therefore, this paper mainly deals with how to evaluating order priority in the mode of make-to-order. For this question, an evaluation index system and a model of fuzzy mathematic system evaluation are established. Through empirical analysis, the model and evaluation system are found feasible and valid.
The Proof of Strong Markov Property Based on one Definition
Authors: Tang Rong , Dong Yi Xuan
Published: March 2015

In this paper, for countable homogeneous Markov process, we prove strong Markov property defining by [2] are valid. So for an arbitrary countable homogeneous Markov process is a strong Markov process.2000 Mathematics Subject Classification. Primary 60J25, 60J27.
Strong Consistency of Maximum Likelihood Estimators in Compound-Sequential Logit Model
Authors: Yin Chang Ming , Li Fang Fang , Su Lian Ju
Published: March 2015

Compound-sequential logit models are extensions of the ordinary logistic regression model, which are designed for complex ordinal outcomes commonly seen in practice. In this paper, we prove strong consistency of the maximum likelihood estimator (MLE) of the regression parameter vector under some mild conditions. We relax the boundedness condition of the regressors required in most existing theoretical results, and all conditions are easy to verify.
A Practical Approach for Digital Forensic Triage
Authors: Jiang Jian Guo , Yang Bo , Lin Sen , Zhang Ming Xing , Liu Kun Ying
Published: March 2015

In order to uncover truths to serve justice, case-related data collected from a digital investigation requires substantial resources to analyze, especially in time-critical situations. At present, however, digital forensics has not evolved to meet this ever-increasing demand. Digital forensic triage is a promising solution, as it is designed to maximize the use of resources according to a system of priorities, and hence the efficiency and effectiveness of forensic examinations can be increased. Nevertheless, the lack of concrete methods limits efforts to implement triage. This paper presents a practical approach that is designed to build a prioritizing solution. In this work a new process model is derived based on the presented approach, and it is particularly suited to scenarios where forensic examiners do not have enough time and resources to conduct a full examination and analysis. An example is described to demonstrate how this approach can be used to meet the requirements of network forensic investigations.
Remote Wireless Control System of Copper Refinery Shorting Switch
Authors: Bai Yu Long , Xu Bao Xiong , Hu Sheng Sheng , Wang Xin , Feng Huan
Published: March 2015

The paper designs remote wireless control system of copper refinery shorting switch in the copper smelting industry, which is composed of in-situ monitor nodes and centralized-control master nodes and can realize remote control and real-time monitoring of shorting switch. Monitor nodes adopt PLC module, temperature monitoring module, LCD module and other in-situ devices. All modules collect switching values and temperatures, and transmit collected signals to master nodes through wireless network, and master modes transfer information to computer equipment in the monitoring end. Centralized-control master nodes send alarm for temperatures exceeding the safety range, control switch operation, and produce switch operation report. The test results indicate that the system is reliable, stable and of significant application value in the metallic refinery industry.
A High Torque Magnetorheological Brake with Three Effective Areas
Authors: Wang Juan , Li Jun Qiang , Gao Zhi Wei
Published: March 2015

A new structure magnetorheological brake with three effective areas was designed, two end surfaces and the cylindrical surface of the rotor work as effective areas, then the effective area was increased with the same volume of the rotor. Depending on the characteristics of the magnetorheological brake structure, the finite element model of the magnetorheological brake was built, the electromagnetic field analysis was performed, then magnetic field quantities of the brake model were got. With the results of the magnetic analysis and the relation between the yield stress and the magnetic field strength of the magnetorheological fluid, the performance simulation of the magnetorheological brake was realized. On these bases, the magnetorheological brake and the mechanical performance test system were developed, the mechanical performance of the brake was researched used the test system, the brake’s properties: torque vs. speed and yield torque vs. current were obtained.
Modeling of the Electro-Hydraulic Actuator for a Dual Clutch Transmission
Authors: Hao Hong Tao , Lu Tong Li , Zhang Jian Wu , Zhou Bin
Published: March 2015

This paper concentrates on modeling of the electro-hydraulic actuator of dual clutch transmission. A dynamic model of the electro-hydraulic actuator based on mathematical description has been developed by using Matlab/Simulink as the simulation platform. The simulated results are consistent with the experimental results, which show the correctness of the model. This model can be used to study dynamic characteristics of the hydraulic actuator of wet dual clutch transmission and to validate control algorithm.
Research on the Modeling and Simulation of Power System for the Single-Axle Parallel HEV
Authors: Zhou Qi Xun , Cao Shi Hong , Ning Tao
Published: March 2015

To research the hybrid powertrain vehicle, a forward-facing model is built in this paper. Based on the modeling method of experimental data, the model of throttle percentage and the torque of the engine is built, and the relation model of fuel consumption and emissions is given. Considering the Integrated Starter Generator (ISG) and its controller, the relation model of voltage, temperature, torque and current is established. According to the vector superposition principle of the engine and ISG torque, the model of dynamic coupling is also built. Considering the various external force along the driving direction of the vehicle, the running equation is given. Aim to a single-shaft parallel hybrid vehicle, the simulation of whole vehicle and the semi-physical simulation of ISG drive system are presented in this paper. Results show that the simulations are rational, and the fuel economy of the vehicle is enhanced efficiently.
The Workspace Analysis of an Improved 6-DOF Parallel Handcontroller
Authors: Song Jing Zhou , Wang Guan Ji , Sun Han Xu , Jia Qing Xuan
Published: March 2015

In order to improve the response effectiveness, extend the workspace of parallel manipulator and make it more conveniently to be used in realistic tasks, this paper has introduced an improved mechanism based on the traditional 6-PUS, which applied the rails leaning outside and the linear motor as its driving system. This has optimized the initial parameters of the improved mechanism, and analyzed its workspace in the software Matlab using the method of cylindrical coordinate search. The result has a guiding significance in optimization of traditional parallel manipulators and the manufacturing of the new prototype.
Research on Warehouse Environment Monitoring and Control System Based on Multi-Sensor Data Fusion
Authors: Wang Yan Wei , Li Ting Hui , Bi Jin Jie , Li Hai Yan , Li Gui Yan
Published: March 2015

Due to the characters of large space and uneven distributing of the temperature and humidity which always exist in the warehouse, the reliability and accuracy of data are influenced when using the wireless sensor network to collect the environmental parameters which are large redundancy and errors. According to the above-mentioned characters, a self-adaptive weighted algorithm based on multi-sensor data fusion was presented. The simulation results show that, the compute of the method is simple, it needs without any prior knowledge of sensor to give the fusion value with least variance, and therefore the proposed method improves the accuracy of measured data.
Research on Measures to Improve Stability of the Power System
Authors: Shi Xiu Feng , Mu Shi Guang
Published: March 2015

This paper first states the importance of power system stability and the classification and characteristics of power system stability. Then according to the static stability and transient stability of power system, this paper introduces the technical measures to improve the two kinds of stability, and analyzes the corresponding effect, and demonstrates the technical and economical problems needing attention when taking all kinds of measures. The study on the power system stability in all situations has great significance to the social development.
Analysis of Electromagnetic Field in Auto Starter Based on Ansoft
Authors: Li Jun , Shu Wei Bin
Published: March 2015

Starter motor is an important part of the auto starting system. The basic electromagnetic field distributions of the starter motor considering the armature reaction have been obtained by using Ansoft software, also the magnetic field and flux density of the air-gap. The results of the Gauss Meter validate the accuracy of the finite element model. The main conclusions are helpful to the performance analysis, model calculation and optimization design of the auto starter.
A Bandwidth Allocation Strategy for Train-to-Ground Communication System of Urban Mass Transit
Authors: Zhang Xin Wen , Dong Hong Hui
Published: March 2015

Train-to-ground communication system as an important part of the train control system , its performance is essential to guarantee the high safety and efficiency of train operation. However, due to the disturbances caused by movement speed of trains ,terrains, and other environmental interferences ,the existing communication system is often unable to provide a high speed link that is stable enough. Therefore, a reasonable bandwidth allocation strategy is necessary to solve the discrepancy between the demanding data rates and the insufficient bandwidth. This paper propose a bandwidth allocation strategy based on 0-1 knapsack problem and Asymmetric Nash Bargaining Solution, which can effectively reflect different bargaining power of all kinds of services, and improve the reliability and security of the transmission system. Finally, we operate a network simulation by NS2. The simulation show that the proposed scheme can enhance the rate of resource utilization ,get small and stable communication delay and ensure reliable transmission of the high-priority services and the safe operation of the train.
Study on Cloud Service Evaluation Index System Based on QoS
Authors: Cheng Cong , Chen Ai Qing
Published: March 2015

It is extremely urgent to study on the scientific and reasonable evaluation index system in this field when small and medium-sized enterprises start turning to purchase cloud services instead of IT hardware. By making use of analytic network process, based on characteristics of cloud services, referring to common QoS properties in cloud service evaluation, 11 cloud service evaluation indexes are established in this paper and each index is quantified.
The Development of PaaS Based on Cloud Foundry
Authors: Du Jian Xia , Sun Xiao Dong
Published: March 2015

Cloud Foundry is the industry's first open source PaaS cloud platform, it supports a variety of framework, language, runtime cloud platform and application environment, the service that allows developers to make applications in a few seconds the deployment and expansion, there is no need to worry about any infrastructure problems. This paper introduces the main steps to build the PaaS service platform: Cloud Controller、 Health Manager、 stager、 service, and discusses the matters needing attention in construction process.
User Activity Based Application-Layer DoS/DDoS Attack Defense Algorithm
Authors: Tsien Yu Lei , Gai Rong Li
Published: March 2015

In application-layer DoS/DDoS attacks, malicious users attack the victim server by sending lots of legitimate requesting packages, which overwhelm the server bottleneck resources. Normal user’s request thus may not be satisfied. The traditional intrusion detection systems for network-layer cannot effectively identify this attack, and recent researches on this kind of attack are mainly for Web servers. This paper proposed a new defense algorithm based on user activity for topic-based Pub/Sub communication servers in mobile push notification systems. Users consuming system bottleneck resources the most can get high scores and thus are considered overactive. With some resource retaken strategy, overactive users’ connections will be dropped according to system performance level. Therefore, the system can get rid of latent threatens. Experiments indicated that this algorithm can identify normal and abnormal users well.
Study on Time of Flight Measurement for Ultrasonic Tomography
Authors: Ren Si Yuan , Liu Shi , Song Can
Published: March 2015

Owing to the distinct advantages, including non-invasive sensing, high safety and low cost, ultrasonic tomography (UT) method is considered as a promising visualization measurement method, in which acquiring high-precision the time of flight (TOF) is crucial for real applications. In this paper, a TOF measurement system is proposed for the UT measurement. The signal analysis is applied for the threshold method to confirm the TOF measurement. The Data acquisition card and the software of Libview are used for the signals acquirement. Experimental studies are implemented to validate the feasibilities of the proposed TOF measurement system, and the experimental results confirm that the TOF measurement system is successful for the TOF measurement.
Voltage Measurement with Improved Multi-Slope Integral Analog-to-Digital Converter
Authors: Zhao Xing Sheng , Wang Xiao Jun , Niu Dan , Li Chao
Published: March 2015

This paper presents a 20 Hz to 200K Hz alternating current (AC) and direct current (DC) analog-to-digital converter (ADC). The strange to minimize the zero crossing noise adopts hysteresis comparison technique. Multi-slope integral technique is also employed to enhance measurement accuracy. Furthermore, an algorism is designed to eliminate measure error. The prototype ADC achieves millivolt precision.
Low Conductivity Material Detection Method Based on Eddy Current and GMR Sensors
Authors: Jiang Kai , Lei Hua Ming , Zhao Hui
Published: March 2015

The low conductivity material such as cancellous bone, cortical bone tissue and soft tissue is the mainly content in the spine. And the improvements on distinguishing the low conductivity material can make a contribution to the spinal fixation surgery process, and protect the patient from spine incident trauma injury during internal fixation prosthetics with implanting pedicle screws. As a result the low conductivity material detection is of great importance in biomedicine study. According to the magnetic property difference of different low conductivity material, an eddy current detection method based on GMR sensor which is proposed in this paper. Compared with coil sensor in traditional non-contact detecting system, GMR sensors have advantages of higher sensitivity, higher precision, better linearity and better stability. Based on this methods, this paper introduces a low conductivity material detection probe. Several experiments indicate that this detection method can detect the low conductivity material NaCl solution with conductivity of 0.128 S/m, whose electrical conductivity matches that of biological tissue. This results lay a solid foundation on the biological tissue detection research.
Preparation and Properties of Wood Flour/HDPE Microcellular Foamed Composites
Authors: Jiang Hong Li , Zhou Jing Lun , Dong Jian , Wang Yu Min , Ruan Jiu Yong
Published: March 2015

The wood flour/HDPE microcellular foamed composites were prepared by means of torque rheometer. The effect of different wood flour content on mechanical properties and foamed behavior were studied. Results showed that the tensile strength and flexural strength of microcellular foamed composites first increased then decreased and the notched impact strength decreased with addition of wood flour, this was consistent with non-foamed composites. The density of composites increased and the density of foamed composites was less than non-foamed composites. With increasing wood flour content, the cell diameter of foamed composites first decreased then increased. When the content of wood flour was 40%, the cell diameter of the composites obtained the minimal value.
An Application of Electron Beam Irradiation for Improving the Peptide Antioxidant Activity and Changing the Microcosmic Surface Morphology
Authors: Li Xing Fang , Lin Song Yi , Wang Zuo Zhao
Published: March 2015

Electron beam irradiation is a chemical technology which mainly applies to food irradiation preservation, radiation sterilization of medical supplies, radiation chemistry and so on. It can change the molecular structure by using the radioactive radiation. In this present study, soybean protein concentrate powder was treated by electron beam irradiation to investigate its effects on the DH, the peptide antioxidant activity and the microcosmic surface morphology. The results indicated that the electron beam irradiation did not have effect on the DH. However, the peptide antioxidant activity significantly increased when increasing the irradiation dose. The highest peptide antioxidant activity 56.84 % was obtained at 3.24 kGy. Scanning electron microscope (SEM) revealed that there were a number of changes to the microcosmic surface morphology after the electron beam irradiation. Not only the shape of the soybean protein concentrate powder particles was changed, but the surface state was changed as well.
The Effect of Different Colloidal Silica Binders on Strengths of Corundum-Mullite Castables
Authors: Yuan Wen Jie , Zhu Qing You , Deng Cheng Ji , Zhu Hong Xi
Published: March 2015

Three kinds of colloidal silica (GS-30, AM and HS-30) were applied as binders to corundum-mullite castables. The apparent porosity and cold modulus of rupture for samples fired at 800 oC and 1000 oC were compared. The fractography of colloidal silica bonded corundum-mullite castables was carried out by slit island method. The microstructure of fracture surface was characterized by scanning electron microscope. The results showed that castables by using imported colloidal silica (AM and HS-30) presented higher strength than those with domestic (GS-30), which was determined by the activity of silica and modified ion. The difference of the size distribution of the salient on the fracture surfaces indicated that the strength of castables was dependent on the bonding among the components.
Heat Treatment of the Hesigewula Lignite and Moisture Adsorption Experiment of its Solid Products
Authors: Wu Ming , He De Min , Chang Shao Ying , Guan Jun , Nie Fan , Meng Tao , Zhang Qiu Min
Published: March 2015

The Hesigewula lignite was studied by heat treatment in a fixed bed and moisture absorption experiment. The temperature of heat treatment was considered as a factor to investigate its influence on product yield. Under the gas carrier (N2) flow rate of 200 SCCM, 0.5 MPa and holding for 20 min, the yield of tar firstly increased and reached the maximum of 5.67 wt% at 500 °C, then came to a decrease with the increasing temperature. The proximate and ultimate analyses of the solid products had been measured. As to the moisture adsorption experiment, the equilibrium moisture content of the solid products at different humidity (30 °C) had been calculated. It was shown that the char of 600 °C adsorbed the least moisture with the minimum content of oxygen. It indicated that heat treatment can remove the oxygen-containing functional group and to some extent upgraded the coal rank.
Catalytic Hydrolysis of Hydrogen Cyanide on Cu-Al Catalyst
Authors: Yan Lin Xia , Tian Sen Lin , Zhang Qiu Lin
Published: March 2015

Cu-Al catalysts were synthesized by the co-precipitation method to study hydrolysis of hydrogen cyanide. During the synthesis, the impact of Cu/Al molar ratio, pH value and calcination temperature was investigated and the best synthesis condition was found. The results indicate that the remove of hydrogen cyanide first increases and then decreases with increasing Cu/Al molar ratio, pH value and calcination temperature, which reaches the maxima and remains above 95% at 360 min when Cu/Al molar ratio is 2:1, pH value is approximately 8.0 and calcination temperature is 400°C around. The analysis of X-ray diffraction (XRD) shows that Cu content is the main influence factor at Cu/Al molar ratio below 2:1 whereas crystallinity of catalysts is the key factor at Cu/Al molar ratio above 2:1.
Pyrolysis of Hesigewula Lignite and Identification of Aromatics in the Pyrolysis Tar by Gas Chromatography-Mass Spectrometry
Authors: Duan Xing , He De Min , Chang Shao Ying , Guan Jun , Nie Fan , Meng Tao , Zhang Qiu Min
Published: March 2015

Hesigewula lignite was studied by fixed bed pyrolysis to achieve the optimal conditions for pyrolysis under low temperature. It was found that the maximum tar yield 6.60wt% under 50 mL/min of gas carrier, 500 °C, 0.5 MPa and holding for 15 min. By column chromatography, we extracted aromatics of the tar generated under the optimal condition. Aromatics with 2 and 3 rings are predominant in the tar from Hesigewula lignite pyrolysis by gas chromatography-mass spectrometry analysis (GC-MS), however, the tetracyclics and above compounds were very few. Naphthalene and its derivatives had pivotal position in aromatics.
Study on Acoustic Emission Signal Frequency Analysis for Diamond Growth Process
Authors: Liu Lei , Sun Guo Ping , Li Mu Sen
Published: March 2015

The growth process of diamond single crystals under HPHT was tested with acoustic emission (AE) technology, and the AE signals were analyzed with fast Fourier transform and wavelet packet analysis. The results show that there are many new frequency peaks in the frequency range that is higher than 80 kHz, and comparative analysis shows that these new frequency peaks are caused from the growth process of diamond crystals. The value of the signal energy and peak in different frequency bands are compared along with the diamond growth process. And it has reflected the dynamic changes in the time domain of the acoustic emission signals stimulated by the different acoustic emission sources. It also shows that the frequency of acoustic emission signals could be used as the effective means to distinguish the different acoustic emission sources in the diamond growth process.
Towards an Atomic-Scale Understanding of the Adsorbate-Driven Formation of High-Index Faces
Authors: Ren Xiu E , Zhang Jian Hui , Lv Xiao Dan , Chen Qi Dan
Published: March 2015

Preferential adsorption takes place at the step ledge between adjacent crystal faces, which usually serve as active sites for breaking chemical bonds. In this paper, we present a structural model to interpret the habit modification of single crystals in terms of the step geometries relationship between crystal faces. A new series of high index faces parallel to the ledge between adjacent facets can be explicitly determined from the presence of the symmetry operators in the space group. The relative stability of these new faces undergoes a faceting transition, driven by the adsorbate-induced changes of the step configuration. Combined with the chemical bond-geometric approach, our predictions accurately reproduce the tapering evolutions of KDP crystals in the present of metallic ions. The current work provides a new insight on how changes affecting elementary steps on one face are translated into the emergence of a new crystallographic face.
Study on the High-Speed Analysis of Coal Qualities by FT-NIR Method Based on Improved Successive Projections Algorithm
Authors: Xu Zhi Bin , Si Xue Bing , Li Cui , Chen Fan
Published: March 2015

To solve the problems of high dimension, multicollinearity, easily over-fitting, this paper further studies characteristic wavelength selection method, and proposes the improved successive projections algorithm based on mean impact value algorithm (SPA-MIV). The results show that the proposed algorithm reduces data dimensions and improves data quality effectively. After being processed by improved successive projections algorithm, the determination coefficient of of testing set of moisture, ash and volatile PLS calibration models are increased to 0.9318, 0.9127, 0.9389, and the of testing set determination coefficient of moisture, ash and volatile BP neural network calibration models are 0.9645,0.9432,0.9536.
Orientation Evolution in the {0001}-Oriented Hexagonal Crystal during Channel Die Compression
Authors: Zhang Fang , Chen Xi , Sha Yu Hui
Published: March 2015

The activity of deformation modes and orientation evolution in the {0001}- oriented hexagonal crystals with basal slip as easy slip mode during channel die compression were investigated by crystal plasticity finite element method (CPFEM). Material parameters of magnesium and its alloys were used in CPFEM simulation. The pyramidal  slip contributes most of the strain in all cases of relative CRSS value and friction coefficient between mold and material. The friction coefficient has a more significant influence on the activity of various deformation modes and the orientation deviation from ideal {0001} orientation (<0001>//ND) compared with the relative CRSS value. The deviation angle can reach about 20° after 70% applied reduction under the friction coefficient of 0.20.
Effects of PTFE and PEDOT:PSS Double Buffer Layers on Flexible Polymer Solar Cells
Authors: Ma Da , Zhang Chun Xia , Zhang Pan Pan , Zhang Li Xin , Dang Yang , Chen Xin , Kang Bo Nan
Published: March 2015

We investigate the effects of polytetrafluoroethylene (PTFE) on organic photovoltaic (OPV) devices with structure of ITO/PTFE/PEDOT:PSS/P3HT:PCBM/PTFE/Al by inserting thermally evaporated PTFE films between indium-tin-oxide (ITO) and PEDOT:PSS layers, and also between P3HT:PCBM and Al, respectively. Significant improvement in terms of open-circuit voltage, Fill factor (FF), and thereby in its commensurate power conversion efficiency is achieved compared to devices with PEDOT:PSS and LiF buffer layers. The OPVs performance enhancement is attributed to the formation of an artificial dipole layer resulting from the rich, negatively charged fluorine that facilitates the charge extraction process.
Research on Corrosive Wear Properties of Super High Chromium Cast Iron
Authors: Li Bao Yuan , Guo Hong Bo , Xu Liu Jie , Wei Shi Zhong , Wu Kun , Yang Xiong , Du Guang
Published: March 2015

National standard high chromium cast iron contains 26% chromium by weight (Cr26). A new type of Super High Chromium Cast Iron (SHCCI) has been developed with chromium content of about 37% by weight. This paper examines the microstructure of SHCCI using SEM and XRD. The hardness and toughness of SHCCI was studied and the corrosive wear properties of SHCCI were also examined using an MCF-30 type erosion abrasion tester under H3PO4 media. The results show that, the microstructure of SHCCI is composed of M7C3 and M23C6 carbides, martensite matrix and residual austenite matrix. With proportionately greater carbon content, the hardness of SHCCI will first increase and then decrease, while the toughness and corrosive wear properties will decrease gradually SHCCI’s corrosive wear performance was significantly better than that of Cr26 cast iron. The maximum wear capacity of SHCCI is three times higher than that of Cr26 cast iron.