bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory Experimental Study on Advanced Water Injection
Authors: Yin Dai Yin , Wang Shuai , Ying Bo , Zhang Cheng Li
Published: November 2012

Advanced water injection can keep a high level of formation pressure, reduce the damage of permeability caused by the drop of formation pressure, and improve the oil displacement efficiency. Through pressure sensitive experiment and Micro-CT scan method, this paper study the influence on rock parameters by formation pressure. The results show that permeability decreases greatly in depressurization development, the permeability restores a small degree after restoring pressure, the change of coordination number and pore throat radius is similar with permeability, and porosity is not sensitive to pressure. Through the research on the influence of oil displacement efficiency by drive pressure, the results show that advanced water injection can improve the oil phase relative permeability, the average increase rate is 5.02%, and also increase oil displacement efficiency, the increase rate is 1%. The core fluorescence images indicate that the remaining oil by advance water injection is obviously less than the conventional production.
Abrasive Wear Mechanism in Near-Nano and Microstructured WC-Cobalt Coatings
Authors: Mateen Abdul , Khan T.I.
Published: November 2012

Abrasive wear mechanism in HVOF sprayed near-nano and microstructured WC-17wt.%Co coatings was studied. The crack propagation mechanism shows that it propagates only through cobalt matrix in the case of near-nanostructured coatings while both trans-granular and intergranular crack propagation was observed in the microstructured coatings. SEM images show a relatively ductile failure mechanism in the near-nanostructured coating, while a brittle failure mechanism dominated in the microstructured coating. AFM images show that the worn surface is smooth in near-nanostructured coatings with an average roughness value of 19 nm, while the roughness on the microstructured coating worn surface was recorded at 83 nm. Further, the wear debris formed on the near-nanostructured coated surface was mostly spherical and finer, whereas this was irregular and coarser in the microstructured counterpart. The wear behaviour suggested a lower wear rate in the near-nanostructured coatings than the microstructured coating. This was further confirmed by abrasive wear tests results.
Boil-Off Gas Formation inside Large Scale Liquefied Natural Gas (LNG) Tank Based on Specific Parameters
Authors: Zakaria Mohamad Shukri , Osman Kahar , Musa Md. Nor
Published: November 2012

Liquefied Natural Gas (LNG) fleets are coasting with various condition and behavior. These variable leads to different type of LNG fleets build every year with unavoidable generated Boil-off Gas (BOG). Estimation of BOG generated inside LNG tank play significant role in determines the ship specification and management method of BOG including venting, propulsion or requalification. Hence, in the present study, the right choices of boundary condition and parameter have been implementing in order to have good estimation amount of BOG evaporates for specific LNG tank. Three dimensional model of cargo with capacity 160000 m3 LNG carrier are simulate using ANSYS Fluent with specific ambient air temperature of 5oC and ambient seawater temperature of 0oC have been chosen as a calculation case, gain the total heat transfer rate and Boil-off Rate (BOR). The result shows that the calculation model and simulation are feasible with typical LNG fleet specification and International Marine Organization (IMO) standard.
Studies of Relationship between Contact Width and Leakage on Large Size of New Metal Gasket
Authors: Choiron M. Agus , Haruyama Shigeyuki , Kaminishi Ken
Published: November 2012

In the previous study, the relationship between leakage and the contact width size that prevent leakage for 25A size of new metal gasket has been examined. In this study, large size of new metal gasket which are 50A, 80A and 100 A sizes were evaluated by using same approach of leak measurement and the relationship between leakage and the contact width. A new approach of leak measurement was performed to clarify the relationship between the presence of leak produced by the water pressure test and the amount of helium leak rate using helium leak test. Moreover, comparing the evaluation results of the relationship between the clamping load and the contact width by using the finite element method (FEM) analysis with the experimental results of the clamping load and the leakage, the contact width which affects the occurrence of leakages on new metal gasket was clarified. The results obtained for these gaskets indicated that the contact width is similar.
Aero-Thermal Performance of Purge Flow in Turbine Cascade Endwall Cooling
Authors: Aizon W. Ghopa Wan , Funazaki Kenichi
Published: November 2012

The endwall and blade film cooling systems are the typical solution adopted within gas turbines to allow further increase of turbine inlet temperature, avoiding critical material thermal stresses. Due to complex secondary flow field in the blade passage, endwallis more difficult to cool than blade surfaces. In the matter of fact, in endwall film cooling studies, it is necessary to investigate the interaction between coolant air and the secondary flow. In present study, the flow field of high-pressure turbine cascade has been investigated by 5-holes pitot tube to reveal the secondary flows behavior under the influenced of purge flows while the heat transfer measurement was conducted bythermochromic liquid crystal (TLC). Experimental has significantly captured theaerodynamics effect of purge flowat blade downstream close to the endwall region. Furthermore, TLC measurement illustrated that the film cooling effectiveness and heat transfer coefficient contours were strongly influenced by the secondary flow on the endwall.
High Speed Experimental Study of Friction Induced Vibration in Disc Brakes
Authors: Magaswaran K. , Phuman Singh A.S. , Hassan Muhammad Zahir
Published: November 2012

Brake dynamic groan noise which is a low frequency phenomena associated with brake stop condition or slow brake release. This phenomenon said to be a friction-speed characteristic and commonly associated with low speed events. Thus a high speed test regarding this phenomenon is done. In conjunction with speed, pressure relation is also tested. Analysis of groan occurrence in relation of the speed and pressure is performed. The pressure relation to this event is expected to widen the study of this phenomenon which currently confined to stick and slip motions.
Extensive Tracking Performance Analysis of Classical Feedback Control for XY Stage Ballscrew Drive System
Authors: Abdullah L. , Jamaludin Z. , Chiew T.H. , Rafan N.A. , Yuhazri M.Y.
Published: November 2012

Performance analysis in term of identifying the system's transient response, stability and system's dynamical behavior in control system design is undeniably a must process. There are several ways in which a system can be analyzed. An example of well known techniques are using time domain and frequency domain approach. This paper is focused on the fundamental aspect of analysis of classical feedback controller in frequency domain of XY milling table ballscrew drive system. The controller used for the system is the basic PID controller using Matlab SISOTOOL graphical user interface. For this case, the frequency response function (FRF) of the system is used instead of using estimated model of transfer function to represent the real system. Result in simulation shows that after proper tuning of the controller, the system has been successfully being controlled accordingly. In addition, the result also fulfill the set requirement of frequency domain analysis in terms of the required gain and phase margin, the required maximum peak sensitivity and complimentary sensitivity function and the required stability.
5A 1300V Trenched and Implanted 4H-SiC Vertical JFET
Authors: Chen Gang , Song Xiao Feng , Bai Song , Li Li , Li Yun , Chen Zheng , Wang Wen
Published: November 2012

A silicon carbide (SiC) vertical channel junction field effect transistor (VJFET) was fabricated based on in-house SiC epitaxial wafer with lift-off trenched and implanted method. Its blocking voltage exceeds 1300V at gate bias VG = -6V and forward drain current is in excess of 5A at gate bias VG = 3V and drain bias VD = 3V. The SiC VJFET device’s current density is 240A/cm2 at VG= 3V and VD = 3V, with related specific on-resistance 8.9mΩ•cm2. Further analysis reveals that the on-resistance depends greatly on ohmic contact resistance and the bonding spun gold. The specific on-resistance can be further reduced by improving the doping concentration of SiC channel epilayer and the device’s ohmic contact.
Research on Programmable Logical Relay Protection
Authors: Liang Li Kai , Zhang Yu Yin , Zhang Xiao Cong
Published: November 2012

In order to improve the flexibility of computer protection on relay protection and to simplify the development process, this paper presents a new method which a programmable logic is applied to relay protection in form of software and hardware platform. The method can better satisfy the needs of relay protection. Aiming at the shortage of traditional relay protection deceive, this paper mainly discuss how to realize the modularization of the new hardware and software platform and to make the theoretical analysis about logic hardware and software platform.
Coulostatic-Based Research on Corrosion Inhibition Mechanism of Three Inhibitors for Hot Dipped Coating Steels
Authors: Ju Hong , Li Yan
Published: November 2012

The corrosion inhibition mechanism of three inhibitors for hot dipped coating steels in HCl acid was studied by coulostatic method. The results showed that the anodic Tafel slope ba and cathodic Tafel slope bc significantly increased with increasing of corrosion inhibitor concentration. While the corrosion current density Icorr decreases with the corrosion inhibition concentration increasing. And the inhibition efficiency increased with the inhibitor concentration. The inhibiting action of these compounds were attributed to blocking of the electrode surface by adsorption through its active centers. The three inhibitors were both mixed inhibitors, and reacted as good inhibition by the adsorption of the active sites in the cathodic reaction and the anodic reaction of corrosion process.
Research on Enhanced Magnetism and Demagnetization Armature Reaction of Double Salient Electro-Magnetic Motor
Authors: Zhu Lin , Zhao Xu Cheng , Hu Heng Sheng , Huang Wei Xing
Published: November 2012

This paper researches on half-bridge rectifier of double salient Electro-magnetic motor. It analysis principles of two rectifier models and studies the armature reaction. Through the experiment of the output of 28.5V on the motor, we find the proper rectifier model for low voltage output of direct current.
Effect of Stator Structure and Field Analysis of a New Type Single-Phase Induction Motor
Authors: Zhong Hui , Wang Xiu He , Zhang Cheng , Yin Ming
Published: November 2012

The new type single-phase induction motors with three stator windings are brought forward for there high efficiency and low cost. However, the unbalance current density in the stator windings is still a problem to the design of this type motor. This paper presents the asymmetrical stator windings and slots structure in the motor design to get the currents density balance. A magnetic field analysis of the new type tri-winding induction motor is preformed using a two-dimensional finite element method. The Maxwell stress method is used to compute the air gap torque that is required for solving the equation of motion. The perfomance of the motor with different structure stator are compared and analysised.
Sliding Mode Control Applied to Aerodynamic Servo System
Authors: Yi Peng , Yuan Rui Bo , Luo Jing , Zeng Hao
Published: November 2012

This paper describes the composition of the aerodynamic servo model, Establishment of a system model based on three equation of fluid dynamics. At the same time, using sliding mode variable structure method control the system has good results.
Study of the Hydraulic Mold System Basing on the Power Bond Graph
Authors: Li Liang , Chen Kui Sheng , Fu Shu Guang
Published: November 2012

This paper mainly introduces the structure and characteristics of the hydraulic mold system. By means of the power bond graph, the mathematical model of the servo system is set up. The analysis is not only to analyze single input and single output system (SISO) but also to analyze multi-input and multi-output system (MIMO).As result of it, it is widely applicable. Finally, we analyze the system dynamic characteristic basing on MATLAB SIMULINK. According to the simulation curves of the different parameters, we find out the system optimization measures.
Numerical Simulation and Vibration Analysis of Inner Flow Field for Lage-Sized Throttle Valve
Authors: Huang Guo Qin , He Ying , Yu Jin
Published: November 2012

Based on the computational fluid dynamics(CFD) technique, the three-dimensional inner flow field of a large-sized throttle valve was built and the dynamics characteristics of the control valve were analyzed. The results indicate that the main reason for the spool and valve vibration was the cavitations at the spool and the whirlpool flow at the outlet of the valve, and the fluid velocity rises as the decreasing of the flow area at the same opening. The research f indings will provide the theory basis for the later throttle valves development and optimization with littler vibration and higher efficiency.
Speed Servo Control of Pneumatic Manipulator Based on Sliding Mode Variable Structure Control
Authors: Zeng Hao , Yuan Rui Bo , He Zu Shun , Yi Peng
Published: November 2012

For a series of non-linear factors of compression, friction, air pressure and load changing in the pneumatic system, it impact seriously on low-speed precision and stability of the pneumatic servo system. As the sliding mode variable structure has a good anti-interference ability and capacity of the model parameter perturbation, In this paper we use the above control strategy to solve the unmodeled part of the pneumatic system dynamics and bounded disturbances, so it can improve accuracy and stability of the aerodynamic servo system. The simulation results indicate that the system combined with sliding mode variable structure strategy has better anti-jamming capability and response speed than the traditional PID control strategy.
Multidomain Modeling of Jet Pipe Electro-Hydraulic Servo Valve
Authors: Cheng Yun Jiang , Wang Shu Han , Xu Xiang Yang , Li Wen Yong
Published: November 2012

The jet pipe electro-hydraulic servo valve is a typical two-stage flow control servo valve, its static and dynamic characteristics are analyzed in this paper. The interaction of the mechatronic and hydraulic system is considered by multidomain simulation tool, the all key parameters are tunable and this provides the optimal possibility to develop a high-performance jet pipe electro-hydraulic servo valve.
The Research of Electro-Hydraulic Proportional Control on Copper Anode Lifting Platform
Authors: Peng Zhi Fei , Yuan Rui Bo , Luo Jing , Li Rong
Published: November 2012

This paper introduces the structure and working principle of the designed copper anode lifting platform. According to the actual working conditions and the structure of the lifting device, hydraulic system of electro-hydraulic proportional synchronous lifting device is designed and its working principle is analyzed. This paper takes the electro-hydraulic synchronization system as a research subject, whose mathematic model is established. To solve the synchronization accuracy of the hydraulic cylinder movement in the lifting process, a model reference adaptive controller is designed which is based on hyperstability theory. Both system simulation models of traditional PID control and adaptive control are established respectively in the software of Matlab/Simulink. Through the simulation result we can learn that adaptive control is batter than the PID control. Two hydraulic cylinders synchronization error is less than 0.02mm.
Research on Low Cost Automatic Polishing Machine for Die/Mold Manufacturing
Authors: Liu Jian Xin , Lv Jian Jun , Tan Ping
Published: November 2012

In order to improve die/mold polishing worker’s environment and polishing automation level, we introduce a kind of low cost automatic polishing machine (LCAPM) with compliant actuator. The actuator is composed of a Tripod mechanism driven by pneumatic cylinders. Proportional valve is used to guarantee precision of cylinder’s position, and a 3D force sensor is used to adjust polishing contact force between grind stone tool and workpiece. Structure of LCAPM is described in detail; pneumatic control circuit and cylinder’s position are modeled in succession. Finally, a computing case of cylinder’s position for given workpiece is shown.
A New Method for Adaptive Blind Source Separation Based on the Estimated Number of Dynamic Fault Sources
Authors: Yang Xiao Yan , Zhou Xiong , Tang Yi Ke
Published: November 2012

In fault diagnosis of large rotating machinery, the number of fault sources may be subject to dynamic changes, which often lead to the failure in accurate estimation of the number of sources and the effective isolation of the fault source. This paper introduced the expansion of the fourth-order cumulant matrices in estimating the dynamic fault source number, plus the relationship between the source signal number and the number of sensors being utilized in the selection of the blind source separation algorithm to achieve adaptive blind source separation. Experiments showed that the source number estimation algorithm could be quite effective in estimating the dynamic number of fault sources, even in the underdetermined condition. This adaptive blind source separation algorithm could then effectively achieve fault diagnosis in respect to the positive-determined, overdetermined and underdetermined blind source separation.
Package-Platform-Mode and the Application on Research of Compressor Maintenance Management System
Authors: Liu Cheng Jun , Tan Feng You , Zeng Huie , Deng Xian Ling
Published: November 2012

In the background of new economical age, the necessity and inevitability of application of knowing-separating–application method and knowledge-to-production and production-to -platform and package-platform-mode (PPM) is introduced. The relative concepts of PPM are set definition. The characteristics and considerations of PPM are studied. For designing of application system complexity and re-usable knowledge module rarely, the application of PPM on research & development of compressor monitoring and diagnosis and maintenance management system-CMDMMS is probed. The PPM is a reliable idea for designing of complex application system.
Research on Modeling Method Based Kernel Principal Component Analysis for Ball and Beam System
Authors: Wang Ze Fang , Song Miao
Published: November 2012

To simulate the human control behavior, and to solve the dimension disaster problem of the simulation model which can simulate complicated controlling behavior, the ball and beam system is researched. The kernel principal component analysis and false nearest neighbor method is adopted, and the simplified ball and beam system controller is designed. The embedding dimension of input time series is determined by the false nearest neighbor method, and then the characteristic value is extracted by the kernel principal component analysis method, so the nonlinear auxiliary variable space feature can be extracted, phase space is reconstructed and the variable is selected. Last from simplified input space to the output space regression mathematical model is fit by using the method of least squares linear regression. Test shows that the control algorithm is effective, with high control precision and stability.
Optimization of Injection Molding Process Parameters Based on Taguchi Design of Experiment
Authors: Li Xue Feng , Liu Hong Bin
Published: November 2012

In this paper, circulating box cover is taken as the main object of the study with the application of Taguchi design of experiment and Moldflow software. The warpage deformation was obtained under different molding conditions including melt temperature, mold temperature, filling time and packing time. The influencing degree and trend of these parameters was studied by using the rang analysis, and the optimization set of factors was obtained. Experimental results show that the optimization design is effective and the warpage of the product reduce.
Experiments and Study of the Static Rigidity of Workpiece Spindle of Direct-Drive Gear Hobbing Machine
Authors: Hu Jin , Zhang Gen Bao
Published: November 2012

Static rigidity of workpeice spindle component is a very important index of the rigidity of derict-drive gear hobbing spindle unit. In this study, the static rigidity of workpiece spindle system were analyzed through a finite element method (EFM) by building geometric models and studying the deformation when radial cutting force was imposed. Experiments on workpiece were carried out with and without the assistance of tailstock center separately to measure the changes of the static rigidity of spindle. The results prove a less change of the static rigidity of spindle when with the assistance of tailstock center, which helps to ensure the accuracy and surface roughness of a workpiece.
Study on Issues Management of Software Project Based on SDP-21 Framework in the Automobile Industry
Authors: Gao Yang , Chen Ting , Yuan Qun
Published: November 2012

System delivery process (referred to as SDP-21) is a mature IT framework system that GM (General Motors Corporation) applies in the project management of automobile industry. For current problems existed in the software project management of automobile industry, this paper introduces an IT project management model based system delivery process (SDP-21 framework). On this basis, presents the methods and procedures for implementing issues management, constructed the process flow of issues management. It will help automobile industry to establish and improve the software planning and project management, give full play to the role of software system in enterprise development. Finally, it can provide the technical support for automobile enterprises to enhance their competitive strength.
Transient Analysis of Inlet Fogging Process for Gas Turbine Systems
Authors: Kim Kyoung Hoon , Kim Dong Joo , Kim Kyoung Jin , Hong Seong Wook
Published: November 2012

Gas turbine inlet fogging is a method of cooling intake air by injecting demineralized water in the duct through the special atomizing nozzles. Gas turbine cycles with inlet fogging could offer enhanced efficiency with low complexity, so the inlet air-cooling is considered the most cost-effective way to increase the power output as well as thermal efficiency of gas turbines. In this work the inlet fogging process is modeled based on the evaporation of droplets. Transient behaviors of the process are investigated with analytic expressions obtained by considering heat and mass transfer and thermodynamic relations. Effects of water injection ratio on the transient behaviors of temperature of mixed air, mass of liquid droplets, mass flux and heat transfer from the droplets are thoroughly investigated. Results show also the dependencies of system parameters on the critical injection ratio and evaporation time.
Directional Pattern versus Omnidirectional Pattern of Switched Beamform Antennas for Asymptotic Connectivity
Authors: Ding Rong , Xiao Ran Dong
Published: November 2012

The connectivity of wireless networks is important for data transmission. Gupta and Kumar have already proved that if n nodes with omnidirectional antennas are located randomly, uniformly in a disk of unit area, the critical transmission range to achieve asymptotic connectivity is O( )[1]. In this work, we studied the network connectivity where nodes equipped with switched beamform antennas are randomly and uniformly distributed in a disc of unit area in R2, the antenna can be modeled in omnidirectional and directional patterns. We ﬁrst assume that nodes in the network cooperate in routing each others’ packets without considering the scheduling, there exists critical transmission range to achieve asymptotic connectivity of the overall network, which responding to critical transmission power. Directional antennas are considered to be a viable solution for improving the network’s connectivity, However, we ﬁnd that, without considering schedule, the smallest critical transmission range was obtained when omnidirectional antenna patterns were used in both the transmitter and receiver instead of directional antenna patterns in our model.
Consensus Function Based on Matrix Factorization
Authors: Liu Li Min , Fan Xiao Ping , Xie Yue Shan
Published: November 2012

Clustering ensemble has been known as an effective method to improve the robustness and stability of clustering analysis. Clustering ensemble solves the problem in two steps:firstly,generating a large set of clustering partitions based on the clustering algorithms;secondly,combining them using a consensus function to get the final clustering result. The key technology of clustering ensemble is the proper consensus function. Recent research proposed using the matrix factorization to solve clustering ensemble. In this paper, we firstly analyze some traditional matrix factorization algorithms; secondly, we propose a new consensus function using binary nonnegative matrix factorization (BMF) and give the optimization algorithm of BMF; lastly, we propose the new framework of clustering ensemble algorithm and give some experiments on UCI Machine Learning Repository. The experiments show that the new algorithm is effective and clustering performance could be significantly improved.
Design of the Autocollimator Interface Based on TMS320F2812
Authors: Gao Li Na , Hu Xiao Dong
Published: November 2012

In order to convenient the design of the autocollimator interface, this paper introduces the design of hardware and software of the autocollimator interface, and detailed analysis some key links. The SPI extension module (EEPROM) based on abundance on-chip resource of TMS320F2812 DSP is used to storage the equivalent of misalignment angle; The CAN extension module (CAN bus) based on CAN module is used to communicate with other computers; SCI extension module (RS232) is used which is convenient for the system debugging, and extension interfaces are left. Meanwhile, the corresponding design of software is also given in the paper. Prototype tests show that the design of the autocollimator interface can fully satisfy the requirements of the system. The design experience can be referred in similar engineering.
The Numberical Simulation on Magnetostrictive Guided Wave for Cracks Inspection in Pipelines
Authors: Long Sheng Rong , Zhong Yu Ning , Song Xiao Chun , Yang Ling Yu
Published: November 2012

Based on the theory of elastodynamics , the relationship between the amplitude of crack reversed echo and the size of crack which detection by the T(0,1) modal is studied by the method of simulation. Based on the simulation result, T(0,1) modal sensitive to a radial crack which length below the perimeter of pipe and the reflection ratio increase as the length of crack raised are got. The T(0,1) modal is insensitivity to a permeate axial crack which length between 20% to 45% of wavelength. The reflectance became minimum when the length arrive at 50% of wavelength, it get maximum when size reach 90% of wavelength, then it has a small decrease till 100%.
Study on Leaking Detecting by Ultrasonic Testing System with Leak Hole Estimation
Authors: Xiao Hui Heng , Wang Tao , Fan Wei
Published: November 2012

The principle of holes leaking create ultrasonic and the relationship between the sound pressure and the pressure or hole size was discussed in this paper. A method of leak hole estimation by the relationship and a design of gas leak ultrasonic testing system were presented. Experimental results which obtained by the gas leak ultrasonic testing system indicated the method is stable, reliable and tallying with the actual results. The method can estimate the leak hole quickly and exactly. Compared with the method of fitting the Reynolds number and amount of leakage, the accuracy has improved to some extent, and it has certain significance in the fast detection of the leak hole size. It could be popularized in the gas leak ultrasonic testing system.
Control System for a Mobile Platform in a Test System of Solar Collector Based on State Machine
Authors: He Tao , You Jun , Xu Li Xiang , Zhong Yu Ning
Published: November 2012

A mobile test system for solar collector is introduced in this paper. The mobile test system for solar collector is a flexible and convenient testing device. Its design is much more difficult than that of a fixed test system for solar collector, because it needs consideration so as to make the test system accurate, reduce the volume of the test system, ensure the stability of the test system, increase corresponding removed devices and so on. For an effective integration of the test system and a vehicle, this paper discusses a mobile platform and its control system. A movement control of the subsystem adopts ac servo system based on PC. The system takes LabVIEW which is used in a virtual instrument as the development platform. And it employs a state machine model to monitor the process of removing and taking back for the mobile platform.
Study on Characteristics of Gas Flow Pressure in Catalytic Converter with Porous
Authors: Cai Zhan Jun , Kang Wei Min , Cheng Bo Wen , Li Ya Bin
Published: November 2012

This paper studies the different porosity of porous medium how to affect the flow pressure field under the conditions of same inlet velocity and fiber diameter by CFDmethod. Geometric model of the catalytic converter has been established and meshed by the pre-processing tool of FLUENT. The flow pressure simulation filled contours and the curve of center line static pressure distribution of the fiber porous material show that in the case of other conditions remain unchanged, the less the porosity of the fiber porous material, the higher the inlet pressure and the more the pressure loss of the porous material. The more porosity of fiber is beneficial to exhaust catalytic reaction.
A Semantic Based Similarity Measure for Human Motion Data
Authors: Zhao Jian Jun , Chen Bin , Yao Gang , Yang Li Bin
Published: November 2012

In this paper, we measure the similarity of human motion data in the terms of distances between trajectories with a semantic method. In order to solve the problem of heavy computation cost, the semantic method that represents a trajectory as a set of 5-D vectors which contains the semantic information are proposed. Through experiments, the semantic method is proved to be efficient for cutting down the computation time and for two kinds of problems: overlapped trajectories with different directions and the trajectories with decoytrenches.
A Digital Menu System Based on the Cloud Client Technology
Authors: Dong Lin , Li Wei Bo , He Ping , Liu Jia
Published: November 2012

Realization of informatization management in the catering industry may be costly. In order to address this problem, this paper put forward a Digital Menu system, which integrated with of the concept of cloud computing and touch screen on the wireless devices. All of the departments’ terminals connected with the server will equip with the Digital Menu System software through the wireless network, and together they reform a Digital Menu System. Successfully adopting such system in the catering industry could potentially reduce the cost of personnel and management. The system employed the follow technologies: Virtual Desktop Protocol (VDP), Wireless Network, Touch panel, Cloud Client etc. It helps informatization process of the catering industry and provides a new manner to order dishes. Using the cloud client technology provides a new method to order dishes for the catering industry.
The Design and Implementation of Home Automation Universal Terminal Node Based on ZigBee
Authors: Lv Jun Ke
Published: November 2012

ZigBee home automation networks is a future trend of intelligent home system. This paper analyses the types and characteristics of home automation terminal node. Based on the chip of CC2530 and Z-Stack protocol stack from Texas Instruments, the home automation universal terminal node is designed. The hardware design adopts modular form with CC2530 as its core, including CC2530 module, sensor module, output driving module and power supply module. For software design, Z-Stack protocol stack is transplanted. Based on the analysis of Z-Stack protocol stack, this paper presents the process of establishing a new ZCL application. Depending on the different types of terminal node, the program flow diagrams are provided. Practice indicates that the design proposal is universal and suitable for terminal node of home automation.
Numerical Simulations of Combustion and Decomposition Processes in Precalciner with Two Types of Locations of Jetting Coal Pipes
Authors: Mei Shu Xia , Xie Jun Lin , He Feng , Jin Ming Fang
Published: November 2012

To reduce energy consumption, numerical simulations of combustion and decomposition processes in a precalciner were carried out with two types of locations of jetting coal pipes. In Euler coordinate system the gas phase is expressed with k-ε two-equation model, in Lagrange coordinate system the solid phase is expressed with discrete phase model (DPM), the chemical reaction is expressed with species transport model, and the radiation is expressed with P1 radiation model. For the base case the predicted burn-off rate of pulverized coal was 86%, and the decomposing rate of calcium carbonate was 92.9%, which are in accordance with actual measurement engineering data. The results show that when the jetting coal pipes are above the tertiary air inlet, the flow pattern of coal streams is more rational in the precalciner, being beneficial to the coal burn fully, resulting in a high temperature zone, around which the calcium carbonate decompose rapidly, than that when the jetting coal pipes are far away from the tertiary air inlet.
Dynamic Hand Gesture Recognition Using Kinematic Features Based on Dynamic Time Warping
Authors: Pang Hai Bo , Ding You Dong
Published: November 2012

Hand gesture provides an attractive alternative to cumbersome interface devices for human computer interface. Many hand gesture recognition methods using visual analysis have been proposed. In our research, we exploit multiple cues including divergence features, vorticity features and hand motion direction vector. Divergence and vorticity are derived from the optical flow for hand gesture recognition in videos. Then these features are computed by principal component analysis method. The hand tracking algorithm finds the hand centroids for every frame, computes hand motion direction vector. At last, we introduced dynamic time warping method to verify the robustness of our features. Those experimental results demonstrate that the proposed approach yields a satisfactory recognition rate.
Research of Image Processing Based on High Frame-Rate Beacon for Free Space Optical Communication
Authors: Cao Yang , Zhao Min Fu
Published: November 2012

It is the key step for real-time image processing of beacon to complete the pointing, acquisition and tracking course between the optical communication terminals. The segmentation and extraction of beacon is the most difficult problem for the sequence image processing, a kind of adaptive threshold segmentation method is put forward on the basis of Otsu algorithm , in the improved algorithm, the image processing is divided into two parts: firstly, it is to identify potential target in a single frame; the secondly, it is to detect beacon image in a region of interesting . Finally, the kalman model is applied to accomplish the tracking of beacon, the experimental result shows that the Otsu algorithm overcomes the disadvantage of incomplete information for traditional algorithm, therefore, it is beneficial to improve the tracking ability of system．
An Improved Algorithm of Spectrum Access in OSA
Authors: Li Sheng Liang , Wang Xiao , Guo Shi Zeng
Published: November 2012

We present a distributed spectrum sensing and access algorithm applied in opportunistic spectrum access (OSA) networks. It is proposed in the condition of cognitive radio (CR) users’ correct spectrum sensing. In each slot, a CR user will decide whether to sense, which channel to sense, and whether to access. However, due to the hardware and energy constraints, the CR users may not be able to sense or monitor all the channels, so we design this access algorithm derived from the theory of Partially Observable Markov Decision Process (POMDP). To simplify the analysis, we assume that the CR users will sense and access only one channel. Simulation results show that the proposed access algorithm can greatly improve the throughput of CR users than the random access algorithm. It has good access performance, and can quickly achieve stable access throughput as well. It is shown that with greater channel transition probability difference the CR users will obtain higher access throughput, and when the difference equals to zero this access algorithm becomes random access algorithm.
Research of Fiber Bragg Grating Sensor Demodulating Technology with Lab VIEW
Authors: Wang Zhe , Yin Zhi Hong , Zhang Ming Xu
Published: November 2012

Combining the virtual instrument technology with the fiber Bragg grating sensing technology, a new fiber Bragg grating sensing demodulation system based on Lab VIEW has been designed. The unbalanced Mach-Zehnder interferometer demodulation technology has been used in this system to translate the fiber Bragg grating wavelength signals in which the strain information is contained into the phase signals，and transfer it to the virtual instrument based on Lab VIEW with the high speed data acquisition card，then conduct process operations and results display [1]. At last, the value of measured strain can be obtained. Compared with the conventional demodulations system，the accuracy this interferometer demodulation system’s measurement has been increased greatly. At the same time, it solves the problem of high cost, large volume and only displays the wavelength with the conventional demodulations system.
The Principle and Structure of Novel High-Precision Linear Time Grating Displacement Sensors
Authors: Peng Dong Lin , Yang Ji Sen , Chen Xi Hou , Chen Zi Ran
Published: November 2012

The existing grating type sensors such as optical grating sensor, have long been designed to rely on the precise mechanical space division technology, which is hard to develop without heavy investment. A theoretical concept, time-space coordinate transformation, was presented to realize measuring spatial displacement with time difference. Similar to the principle of circular time grating based on rotating electrical machine, linear time grating is designed based on the principle of linear motor, with which the physical and mathematical models of linear time grating are established. Based on these models linear time grating mechanical structure is designed, which has commercialization value. The resolution of linear time grating can achieve 0.1μm tested by National Institute of Measurement and Testing Technology.
Design of an Ultra-Low Power Timer System Based on C8051F410
Authors: Peng X.J. , Xiong C.R.
Published: November 2012

This paper proposes an ultra-low power design based on C8051F410 which is used in a timer system for industrial production and device detection failure occurred at a time and the record of relevant information. Two aspects like system hardware circuit and software design of the ultra-low power timer system are demonstrated. This system features low power consumption from the entire system, including the Chinese man-machine interface which consumes only 1mA power cost. This system is suitable for the situations where battery power is limited.
A Method for Vibration-Cylinder Air-Pressure Sensor Temperature Compensation Based on Radial Basis Function (RBF) Neural Network
Authors: Ren Yan , Xu Duan , Qin Fang Ling
Published: November 2012

There is a nonlinear measurement error of the vibration-cylinder air-pressure sensor when the environment temperature changes; To solve the problem, the paper carried out a research on vibration-cylinder air-pressure sensor temperature compensation based on radial basis function(RBF) neural network; The temperature error characteristics of the sensor was studied; The sensor temperature compensation of RBF neural network structures and algorithms was designed; The centers, variances, weights, and the hidden layer neuron number of the radial basis function were determined. The experiments showed that the trained RBF neural network can approximate the input-output relationship of the vibration-cylinder air-pressure sensor in high accuracy.
Estimation for Bearing Preload of Machine Tool Spindle Based on Vibration Signal
Authors: Xu Tao , Xu Guang Hua , Zhang Qing , Hua Cheng , He Qian Qian
Published: November 2012

A significant source of noise and vibration in high speed machine tool spindle is bearing induced vibration, which is caused by geometrical characteristics and interactions between rolling members with surface irregularities. In this paper, analytical approach was proposed to calculate the bearing internal load distribution of spindle, with consideration of the operating conditions. The influences of operating conditions to internal load distribution, contact angles were analyzed. Furthermore, the estimation of power spectral density (PSD) method was used to analyze determination of bearing frequencies. The bearing preload of machine tool spindle was estimated according to the change of ball bearing frequencies. Experiments were carried out in a spindle bearing test rig to verify the validity of the presented analytical method. The method described in this paper can achieve the estimation for bearing preload of machine tool spindle.
Researches Regarding the Nature of the Embeddings in the Cast Pieces Made of Aluminium Alloys
Authors: Cristian Predescu , Eugeniu Vasile , Mihaela Predescu Andra , Gabriela Sohaciu Mirela , Constantin Berbecaru Andrei
Published: November 2012

The paper presents the results of the investigations made on cast pieces consisting of aluminium with Si and Mg mixed metals, in order to establish the nature of the embeddings and the causes that led to their appearance.
Five-Phase Half-Controlled Bridge Commutation and Stabilizing Voltage Nd-Fe-B Permanent-Magnet Generator for Light Vehicle
Authors: Hu Jian Long , Zhang Xue Yi , Zhang Wen Fu
Published: November 2012

Nd-Fe-B permanent-magnet generator provides DC power for the electrical equipment of light vehicle and charges the battery. The rotor of this generator is constructed by several fastening segments of Nd-Fe-B permanent-magnet material onto the iron core through pole shoes by nonmagnetic bolts with adjacent magnet segments opposed to each other in polarity, i.e. N poles and S poles arrayed alternately. When the rotor rotation, hence the magnetic field rotates, the armature winding cuts the magnetic line and produces electromotive force. The developed five-phase half-controlled bridge commutation and stabilizing voltage adjuster combines both functions of voltage stabilization, commutation, and output direct current (DC) with stable voltage. The instability of output voltage was overcome when the permanent-magnet generator for light vehicle ran at wide range of speed and load.
Application of Virtual Substance in Launch Dynamics Simulation for Self-Propelled Guns
Authors: Chen Shi Ye , Wang Liang Ming , Shi Wei
Published: November 2012

To establish more accurate and effective gun dynamics model, which considered fully the coupling influence of projectile and flexible barrel, by introducing the virtual substance into the barrel system, a modeling method for self-propelled guns was presented. Taking a tracked self-propelled gun for an example, combining Ansys and Recurdyn, a multi-body dynamics model was built up. The correlation curves between the experimental data and the simulation result under the same firing conditions were obtained. The results show that the model can describe accurately the dynamic response and the projectile movement, which can provide theoretical references for the further research on gun launch dynamics characteristics.
Design of the Gear Database Based on UG Secondary Development
Authors: Yuan Ming Hai , Ding Yue , Ji Ai Min
Published: November 2012

This paper, based on Unigraphics NX6.0, made use of UG’s strong parametric modelling technology and secondary development module of UG/OPEN API, used the technology of ADO to achieve technical applications and databases interface, and integrated with database and MFC, to develop a gear CAD library system ,and achieve the aim of parameterization modelling and data management of gears.
Research on Improvement the Second Harmonic Signal to Noise Ratio Using Pulse-Inversion Technique
Authors: Yan Bing Sheng , Zhang Shi Xiong
Published: November 2012

Material degradation is usually preceded by nonlinear ultrasonic, and higher harmonics will be generated. The project studied the method to improve the second harmonic signal to noise ratio with pulse-inversion technique. A finite element method model of nonlinear was established by a special element which account for a nonlinear stress-strain relation. Calculation was performed for the influence of the pulse-inversion technique to ultrasonic nonlinearity parameters. The simulation results show that the second harmonic signal to noise ratio is obviously improved. Measurement method of nonlinearity parameters and signal processing algorithms with pulse-inversion technique were established, and a robust experimental procedure was developed. Using this method, ultrasonic nonlinearity parameters of a group of LY12 aluminum samples stretched were measured. The experimental results show that the pulse-inversion technique is very efficient in extracting this second-harmonic amplitude by canceling out the odd harmonics which are mainly due to the instrumentation. Introduction
Study on Application of Process Analysis in Mechanical Processing Industry
Authors: Huang Zong Xiang , Li Bao Ping , Li Chun Guang
Published: November 2012

This paper primarily makes an analysis and study on existing production processes adopted in production lines of mechanical processing industry, and adopts methods of process analysis and work analysis, principles of “ECRS”, 5W1H questioning and improvement analysis sheets and relevant techniques to perform detailed analysis on the existing production processes in respect of complicated process settings, unreasonable processes and other problems in processes of production. According to field observations and data collected, measures are proposed to solve such problems like low efficiency in material flows, waiting of parts, long hauling distance etc. and process improvement plans are made on basis of facilitating reasonable material flows and benefits maximization. The results of analyses and appraisals on new plans show the efficiency of production processes has been improved effectively, which will make it possible that enterprises reduce costs and enhance their competitiveness further.
Design and Simulation of Passive Controller for Guided Rockets
Authors: Bian Wei Wei , Wang Liang Ming , Zhong Yang
Published: November 2012

In order to increase the density of guided rockets, a passive control method was proposed to reduce the trajectory dispersion caused by initial disturbances, thrust misalignment, vertical wind, etc. at the end of boost phase. The basic principle of passive control method was introduced briefly, and then the disturbance motion equations for the rocket projectile were established. The effective conditions to implement passive control on guided rockets were put forward. A technical scheme of installing elastic sabots on rocket projectile was proposed to realize passive control and a simulation was conducted. The simulation results indicate that the passive control scheme can effectively decrease the velocity direction deviation caused by various disturbances factors at the end of boost phase.