bluuebunny/crossref_metadata_2025 huggingface dataset:
The Efficient Synthesis of 1,3-Diallyloxy-2-Propanol without Solvent
Authors: Liu Xi Mei , Hu Yu , Feng Li Hua
Published: August 2011

An efficient and practical protocol for the preparation of 1,3-diallyloxy-2-propanol has been developed by one-pot reaction between epichlorohydrin and allyl alcohol in the presence of KOH without solvent at room temperature. This preliminary approach provides an environmentally-friendly synthetic route to 1,3-diallyloxy-2-propanol with many advantages, i. e., low cost, high yield, easy purification, mild reaction conditions, and large scale production.
Study on Microstructure and Corrosion Behavior of Ag-Cu-Zn-Ni Alloys
Authors: Huang Fu Xiang , Yin Ping , Xu Yong Hong , Zhang Ying
Published: August 2011

Potentiodynamic electrochemical tests and surface analysis technics, such as scanning electronic microscope (SEM), energy dispersive spectrum (EDS) and X-ray diffraction analysis (XRD), were applied to investigate the microstructure and corrosion behavior of Ag-Cu-Zn-Ni alloys in Na2S solution. The results reveal that the α-Ag phase is the main matrix of the studied silver alloys. The second phase of Ag-4Cu-0.3Ni and Ag-3Cu-Zn-0.3Ni/Ag-6Cu-Zn-0.3Ni are respectively CuNi and CuNi(Zn) phases. The second phases of Ag-6Cu-Zn-0.3Ni are well-distributed, which leads to an improvement in the corrosion resistance in Na2S solution.
Experiment Research and Numerical Simulation of an Innovative Seismic Isolating System Designed for Long-Span Continuous Girder Bridges
Authors: Sun Cong , Gao Ri
Published: August 2011

To enhance the earthquake resistance capacity of long-span continues bridge, theory and design of a new seismic isolating system are proposed based on the utilization of improved carbon structural steel material. Pseudo-static test result of the damping tenon, one essential energy dissipation component, proved the system’s excellent characteristic of consuming earthquake energy. Comparative experiments of three models reflect the working stability of the damping tenon confronted with different stimulation. Finite Element simulation further validates accuracy of the experiment and helps analyzing the material’s elastic and plastic developing status due to different load steps. Finally, this new seismic isolating system is recommended to long-span continues girder bridge designed on the basis of high level earthquake resistant standard.
Semi-Active Control of a Vehicle Suspension Based on Magneto-Rheological Damper
Authors: Chen Jie Lai , Jiang Xue Zheng , Xu Ning
Published: August 2011

The focus of this study is to experimentally investigate a semi-active magneto-rheological (MR) damper for a passenger vehicle, by using a quarter car models. After verifying that the damping force of the MR damper can be continuously tuned by the intensity of the magnetic field, a full-scale two-degree of freedom quarter car experimental set up is constructed to study the vehicle suspension. On-off skyhook controller is employed to achieve the desired damping force. The experimental results show that the semi-active vehicle suspension vibration control system based on MR dampers is feasible and can effectively improve ride comfort of vehicle.
Experiments and Analysis of Bending Dielectric Elastomer Actuator
Authors: He Xin Sheng , Gao Chun Fu , Wang Bing , Luo Zhi Yong
Published: August 2011

A kind of compact bending dielectric elastomer actuator is designed and manufactured using VHB4910 as the actuating material. In the contrastive experiments, the maximum displacement of 6.1mm can be achieved, and on the voltage differences of 0.9kv, the active bending of actuator is 8.1°. The research of dielectric elastomer actuator can provide an instruction for the design, analysis and implementation of this kind of actuator.
Adaptive Variable Speed Control of Wind Turbines
Authors: Wang Wei Na , Li Ru Mei , Song Yong Duan , Hu Yong Sheng , Zhang Xub Kui
Published: August 2011

The uncertain and random characteristics of wind energy make the problem of wind turbine control interesting and challenging. This work investigates an adaptive method for variable speed control of wind turbines under varying operation conditions. For fixed-speed operation of wind turbines, maximum power conversion can be achieved only at a particular wind speed, thus variable speed control of wind turbines is of practical interest in enhancing wind turbine operating efficiency over wide wind speeds. Based on the nonlinear dynamic model of wind turbine, adaptive algorithms are developed in accommodating unknown system parameter uncertainties. This method is shown to be able to achieve smooth and effective tracking of rotor angular speed to capture maximum wind energy. The effectiveness and adaptation of the proposed approach is validated via numerical simulation.
Preparation and Properties of Polyvinyl Chloride/Nitrile Butadiene Rubber/Barium Sulfate Composites
Authors: Wu Hao , Cao You Ming
Published: August 2011

The composites composed of PVC, NBR and BaSO4 particles were prepared by melt blending method. The mechanical properties, microstructure and thermal stability of the composites were investigated. The results indicated that the elongation at break of PVC was greatly improved by addition of NBR, while the tensile strength was decreased. The elongation at break and the tensile strength of PVC/NBR composites first increased and then decreased with the increasing content of BaSO4, and the maximum were emerged at 5phr BaSO4 addition. The initial decomposition temperature of the composites composed of PVC, NBR and BaSO4 is 10.79°C greater than that of the composites composed of PVC and NBR. The scanning electron microscopy photograph showed that NBR and BaSO4 particles were uniformly dispersed in the PVC matrix when the addition of NBR and BaSO4 particles was low.
Effect of Forging on Microstruture and Mechanical Properties of In Situ TiBw/Ti Composite
Authors: Chen Yuong , Zhang Chang Jiang , K.S Rahoma Hasan , Kong Fan Tao , Xiao Shu Long , Liu Zhi Guang
Published: August 2011

Ti-6Al-2.5Sn-4Zr-0.7Mo-0.3Si-0.3Y alloy matrix composite reinforced with 7%vol TiB whiskers was fabricated by Induction Skull Melting (ISM) technique and one-direction forged technology utilizing the reaction between titanium and TiB2. The microstructure, room temperature and high temperature mechanical properties have been presented and discussed. Microstructural analysis of the composites revealed that the microstructure was significantly refined and TiB whiskers were made to align the longitudinal direction after forging. It shows that the tensile strength and ductility of the composites has a significant improvement, especially at room temperature.
Preparation and Test of Hierarchical α-Ni(OH)2 Flowers and Spheres
Authors: Li Chang Yu , Liu Li Li , Liu Shou Xin
Published: August 2011

α-Ni(OH)2 with hierarchical structures were synthesized via a simple route using Ni(NO3)2•6H2O and urea as the starting materials. The experimental results from XRD and FT-IR showed that the samples prepared by this method had the typical α-phase and the size of samples can be control by adjusting the reaction conditions. SEM images showed many uniform flowerlike or spherelike architectures with diameters of 4-6μm consisted of dozens of nanosheets. The effects of nickel sources on the phase and morphology of the prepared samples were studied, the nickel sources had an effect on both the crystallinity and size of the prepared samples.
First-Principles Study of Triangle Terarylene as a Possible Optical Molecular Switch
Authors: Xia Cai Juan , Liu Han Chen , Yin Ji Xin
Published: August 2011

Using non-equilibrium Green’s function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of a triangle terarylene(open- and closed-ring forms) optical molecular switch. The influence of the HOMO-LUMO gaps and the spatial distributions of molecular orbitals on the quantum transport through the molecular device is discussed. Theoretical results show that the conductance of the closed-ring is 3-8 times larger than that of open-ring, which expect that this system can be one of good candidates for optical switches due to this unique advantage, and may have some potential applications in future molecular circuit.
Research on Preparation, Characterization of Novel Nano-ZnO
Authors: Liu Yan Yan , Zheng Dian Mo
Published: August 2011

Zinc acetate and ammonium bicarbonate are used as raw material, zinc oxide prepared by direct precipitation of new technology. This paper discusses the effection of the formation in zinc oxide from the reactant concentration of zinc acetate, HCO3-/Zn2+ molarity ratio, reaction temperature, reaction time and condition in thermal decomposition of basic zinc carbonate. Using transmission electron microscopy (TEM), thermogravimetric / differential thermal analysis (TG / DTA) and other methods, preparation of nano-ZnO are characterized. Good conditions for the better system of nano- ZnO are 0.75mol /L in the concentration of zinc acetate solution, 2.5:1 in bicarbonate of ammonia and zinc acetate molar ratio, 45 °C of reaction temperature, 1.0h of reaction time, and 350 °C in thermal decomposition temperature, 3.0h of pyrolysis time. Zinc oxide obtained average particle size is 20 ~ 80nm, for the hexagonal crystal form.
Finite Element Simulations of Crack Initiation in Ultra-Fined Polycrystalline under Cyclic Deformation
Authors: Wu Bo , Li Hui , Zou Na , Tan Jian Song , Hu Ding Yun
Published: August 2011

A finite element model is developed in this paper for simulating cyclic deformation in ultra-fined polycrystalline metals. The grain material is characterized by conventional theory of mechanism-based strain gradient plasticity (CMSG). A cohesive interface model was used to simulate the initiation and propagation of intergranular cracks. The simulation results show that inhomogeneous plastic deformation induces high strain gradient effects and severely plastic hardening in the grain interior, and the intergranular crack has a significant influence on the overall mechanical properties of ultra-fined polycrystalline metals subjected to cyclic loading.
Modeling of Cyclic Super-Elastic Behaviors of Shape Memory Alloy
Authors: Zhou Bo , Yoon Sung Ho
Published: August 2011

This paper focuses on the modeling of the cyclic super-elastic behaviors of SMA. Cyclic tensile experiments are performed on the NiTi SMA to test its cyclic super-elastic behaviors. A material parameter evolution equation is supposed to express the cyclic effects on the material parameters of the SMA. A cyclic constitutive equation is developed to describe the stress-strain relationship of the SMA under cyclic load. Numerical results show that the cyclic constitutive model, which includes the material parameter evolution equation and cyclic constitutive equation, well predicts the super-elastic behaviors of the SMA subjected to cyclic load.
Study on the Cleanliness of 316L Stainless Steel
Authors: Li Gang , Li Jing She , Yang Shu Feng , Wang Yan Jie , Li Nai Song
Published: August 2011

The process of three-phase electroslag furnacefoundry casting  electroslag remelting was used to produce 316L stainless steel ultra-fine wires with a diameter of 0.018mm. Breakage of the wire often occurs during drawing process due to the existence of inclusions in the steel. In order to improve the cleanliness of 316L steel, the deoxidizer and top slag composition were optimized by industrial trials in this production process. As a result, the total oxygen (T.O.) content decreased from 120 ppm to 57ppm. During the electroslag remelting process, the composition of electroslag and the power supply were optimized. Argon protection was used and electrode was washed by acid solution before refining. Finally, the T.O. in the remelting ingot can be controlled below 20 ppm.
Compare of Wear Properties and Analysis of Wear Mechanism about TC4 Alloy and P110 Tubing Steel in Dry Condition
Authors: Yao Xiao Fei , Xie Fa Qin , Zhao Guo Xian , Han Yong , Wu Xiang Qing
Published: August 2011

Using as high strength and corrosion resistance of tubing material, the wear properties of TC4 alloy and P110 tubing steel were comparatively studied, the differences and similarities were analyzed that are weight loss of wear rate and friction coefficient and topography of wear mark, the wear mechanism was discussed. The results showed that the topography of TC4 alloy and P110 tubing steel are different entirely, TC4 alloy is furrow, P110 tubing steel is wear pit, the wear resistance of P110 tubing steel is excelled obviously than TC4 alloy, the wear mechanism of TC4 alloy is delamination wear and adhesive wear and fatigue wear. The wear mechanism of P110 tubing steel is delamination wear and abrasive wear.
Errors Analysis and Compensation of Six-Axis Force Sensor Based on Stewart Platform
Authors: Wang Zhi Jun , Yao Jian Tao , Hou Yu Lei , Zhao Yong Sheng
Published: August 2011

Six-axis force sensors based on Stewart platform necessitate highly accurate, sensitivity and dynamic response. In response to this need, errors analysis and compensation of the force sensor are essential. In this paper, the measurement error generated by the upper platform deformation is discussed and evaluated. Furthermore, in order to improve the precision, a real-time compensation algorithm is proposed depending on the external force applied on the force sensor. Finally, a numerical simulation example is presented, which indicates that the precision is related to the stiffness of limbs directly and improved obviously by the compensation algorithm.
Design and Modeling of a Spherical Actuator with Three Dimensional Orientation Measurement System
Authors: Chen Wei Hai , Zhang Liang , Guo Fang Hong , Liu Jing Meng
Published: August 2011

This paper presents the design and modeling of a permanent magnet spherical actuator which consists of a rotor with eight cylindrical permanent magnet (PM) poles and a stator with twenty-four air-core coils. Torque and dynamic model of this PM spherical actuator are formulated analytically. An optimal design procedure is proposed to achieve a high torque output, and significant design parameters of the actuator are discussed. As there is no effective method for three dimensional orientation measurement of the spherical actuator currently, a novel orientation measurement system is proposed. Finally, experimental works are carried out, and the experiment results demonstrate the effectiveness of the proposed orientation measurement system.
A Kind of Improved Triangle Centroid Algorithm Based on RSSI-Ranged
Authors: Zhu Lin Na , Jiang Hai Feng
Published: August 2011

Node self-localization is one of the key technologies in the wireless sensor networks. The localization technology based on RSSI is a focus studied at the present stage. For the localization error of RSSI-ranged method is relatively great, a kind of triangle centroid algorihms based on RSSI-ranged is proposed. The simulation results show that measurement error of this algorithm effective decrease as to tranditional triangle centroid algorithm based on RSSI-ranged.
Evaluation of VDMOS Storage Failure Rate Based on Accelerated Factor
Authors: Wan Ning , Guo Chun Sheng , Feng Shi Wei , Zhang Guang Chen , Zhou Zhou
Published: August 2011

The method of evaluation of VDMOS storage failure rate is presented and explained in this paper. To obtain a large number of devices working hours in a short time, the accelerated factor k is brought into the failure rate test, from which the test time can be reduced to 1/k. In this paper, the failure rate test of VDMOS is carried out at 270 °C about 1500 hours with the accelerator factor k=21.73079. The storage lifetime of VDMOS was calculated over 10 years. The key parameters have been measured and reliability of VDMOS in ten years storage time has been evaluated.
Mine Hoist Bearing Condition Monitoring and Fault Diagnosis System Based on Labview
Authors: Wan Li Rong , Zhou Guang Yu , Wang Cheng Long , Zhao Wen Ming
Published: August 2011

By taking full advantage of the technologies of data acquisition, signal analysis and processing and fault diagnosis, this thesis carries out a research on the realization method of mine hoist bearing condition monitoring and fault diagnosis. Firstly, this thesis takes a technical analysis for rolling bearing. Secondly, based on determining the overall framework and using a virtual instrument software (Labview), it carries out a program development of the system. The developed system not only integrates the functions of traditional instruments, but also describes the bearing states and the types of bearing failure accurately according to the running status of the monitored bearings. It provides technical support for the mine hoist repair and maintenance and scientific protection for its safe running.
Fuel Identification Based on the Least Squares Support Vector Machines
Authors: Huang Yao Song , Liu Shi , Li Jie , Jia Lei , Li Zhi Hong
Published: August 2011

The identification of the fuel types plays an important role in ensuring the safety and economics of the power plants. In order to obtain the flame signal in the process of combustion, a flame detection system is designed and a laboratorial platform is constructed. This paper extracts the signal parameters—the mean, the peak-peak value, the flicker frequency, and the flicker intensity —and takes them as the characteristic quantities of the flame signal. Based on the least squares support vector machines (LSSVM), an efficient method of identifying the flame types is developed. The result of the identification is more ideal, with the correct identification rate up to 100%. This shows that the method combined the four characteristic quantities with the LSSVM can obtain a good result in the identification of the fuel types.
Detection and Identification of Leakage Signal in the Explosive Gas Atmosphere
Authors: Wang Qing Liang , Zhang Lu , Fu Zhou Xing , Du Hui
Published: August 2011

Leakage is one of big security risks in the explosive gas atmosphere. In view of the weak current and detection difficulty of leakage signal, a novel method of leakage detection is proposed. According to leakage transient characteristics, this method takes zero-sequence voltage as the fault threshold value triggering measurement device. Auto-correlation function is used to analyze leakage signal energy and cross-correlation function is used to calculated leakage signal phase relationship in order to identify leakage line further. Theoretical analysis and simulation show that the proposed method can greatly improve the sensitivity of weak leakage signal detection.
Research on Five Sections Measuring Model in Process Pneumatic Measurement System for Inner Hole Honing
Authors: Ning Hui Feng , Li Xiao , Gong Jun , Xu Hong Tao
Published: August 2011

A novel concept to estimate the shape of inner hole in course of honing is presented in this paper. Based on analysis of machining condition, five sections measuring model is established in process pneumatic measurement system for inner hole honing. It used matrix algorithms to simplify judging process about inner hole shape. And it improves the accuracy of machining area in inner hole. The method and principle are elaborated in this article. Program module was designed and written for experiment. And the experimental data show that the measuring model is feasible.
Analysis of Field Reliability of Two Models of Heavy Vehicles
Authors: Xu Jing , Jiang R. , Zhou Hao
Published: August 2011

A steel mill uses four functionally identical heavy vehicles manufactured by two different manufacturers. The information of failure time and downtime is available. This paper aims to compare the field reliability of the vehicles based on the field repair reports. A cost model is developed to comprehensively evaluate the overall performance of the vehicle. The preventive maintenance frequency of the vehicle is determined based on an empirical approach. The study is useful for the manufacturer to have a clear picture on the competability of its product and is also useful for the user to select an appropriate model of vehicles.
Analysis of Dynamic Behavior of Zigzag Groove Setback Arming Device with Two Degree of Freedom
Authors: He Guang Lin , Tian He Fei
Published: August 2011

Focusing on the requirements of safety and reliability of fuze setback arming device of rocket-assisted projectile, a zigzag groove setback device with two degree of freedom was designed with Inventor 6. The dynamic simulation is developed under environment of VisualNastran. The optimum parameters of up inertia-cylinder mass, down inertia-cylinder mass, up inertia-spring rigidity and down inertia-spring rigidity were tested by orthogonal method and simulated. The results indicate that this setback device can effectively differentiate setback overload in launch and impact overload at service handling; credible arming time of fuze is about 128ms when the even overload of the rocket engine is 100g; the optimum mass of up inertia-cylinder and down inertia-cylinder are respectively 3.19g and 1.41g, the optimum rigidity of up inertia-spring and down inertia-spring are respectively 32.7 N/m and 21.8 N/m.
A Security Improved Remote Password Authentication Scheme Using Smart Card
Authors: Jing Chao
Published: August 2011

Increasing number of network applications require authentication of the user's identity which is the first step to ensure security. This paper analyzes the security performance of one proposed remote two-factor user authentication scheme and discusses the attacks it suffers. Then we propose an improved scheme based on the RSA cryptography and one-way secure hash function to avoid the attacks it suffers. After that we prove the proposed scheme is autonomous and effective for both sides in the authentication process.
Association Rule-Based Novel Incremental Updating Algorithm
Authors: Li Jian Hong
Published: August 2011

This paper focuses on an important research topic in data mining (DM) which heavily replies on the association rules. In order to deal with the maintenance issues within the background of the static transaction database, there are some minor changes to minimum support and confidence coefficient. A novel algorithm based on incremental updated is proposed, which is termed as NIUA (Novel Incremental Updating Algorithm). IUA uses association rules to mining the database, aiming at finding the potential information or finding the reasons from massive data.
The Development of a New Type Aluminium Anode for Deepwater Cathodic Protection
Authors: Li Wei Li , Yan Yong Gui , Chen Guang , Zhang Fan
Published: August 2011

The electrochemical behaviour of a new type Al-Zn-In-Mg-Ti-Ga-Mn anode suitable for deepwater cathodic protection was investigated. The current efficiency experiment was carried out in various simulated deepwater environment, and the EPMA and SKP technologies were also used. The results showed that the anode had uniform dissolution morphology in simulated deepwater environment. The current efficiency was always higher than 90% in all the experiment conditions.
Application of Quaternary Aminated β-Cyclodextrin Ionic Liquid Stationary Phase in Capillary Gas Chromatography
Authors: Zhang Lin Xia , Liu Tao , Luo Ai Qin
Published: August 2011

Two kinds of quaternary aminated β-cyclodextrin ionic liquids were synthesized and used as stationary phases in capillary gas chromatography. The influences of different counter ions (tetra- borofluoride, bis-trifluoromethanesulfonylimide) were studied. The results indicated that quaternary aminated β-cyclodextrin ionic liquids possessed good column coating properties and a chromatographic separation abilities. The Grobs mixture, alkanes, alcohols and aromatic position isomers, such as xylene, nitrotoluene, dichlorobenzene and cresol were separated well. These quaternary aminated β-cyclodextrin ionic liquids have potential to separate some complex compounds including alcohol, amine, ester etc.
Development of in-Pipe Robot with Controllable Magnetic Force
Authors: Yoon Kyung Hyun , Park Young Woo
Published: August 2011

Pipes are everywhere; they are used in a variety of pipelines that should be inspected and maintained to ensure their safety and integrity. Currently, the in-pipe robot for such applications is considered as one of the most attractive solutions available. The most important thing, in-pipe robot must concerned adhesion mechanisms. Several adhesion mechanisms have been proposed and developed. We applied magnetic adhesion mechanism. Magnetic adhesion on in-pipe robots has some advantages such as fast locomotion, no additional energy for adhesion process, and one definite disadvantage like difficulty to control magnetic force. To solve this disadvantage, the permanent magnetic wheels that allow controllable magnetic force. This paper proposes a new in-pipe robot that applied controllable magnetic wheel. The idea is conceptualized, simulated, fabrication, and validated experimentally. The pulling force increases linearly form 8 newtons (N) to 26 newtons. It means that the proposed method is effective to control magnetic force between the wheel and interior surfaces of ferromagnetic pipes.
Optimal Interpolation Algorithm Research Based on Quasi-Hermite Space Curve
Authors: Liang Chang Chun , Fan Liu Qun , Qi Dang Jin , Yi Gang , Miao Zhuang
Published: August 2011

According to the principle of parametric curve paths CNC interpolating, a real-time interpolation algorithm based on algebraic index of the micro-segment spline is presented. It’s used to solve the problems of Hermite polynomial interpolation algorithm, which are commonly slow recursive algorithm, poor accuracy of approximation and the limitations of constant parameters increment interpolation. And the constant interpolation is achieved by fitting a first-order Taylor Formula. Simulation results show that the algorithm shortens the interpolation time and also improve the interpolation accuracy; meanwhile, it maintains the stability of the feed rate.
Optimization of Hydrolysis Pretreatment Conditions with Two Kinds of Enzymes for Enhanced Proteolysis in Egg Yolk Solution Using Response Surface Methodology
Authors: Yu Na , Qin Jia Yan , Bao Hong Yu , Yue Xi Qing
Published: August 2011

Response surface methodology was used to optimize proteolysis of egg yolk solution using Alcalase and Flavorase according to three conditions, the ratio of two enzyme concentration (Alcalase and Flavorase), pH values and hydrolytic time. The responses degree of hydrolyzation (DH) and peptide yield were studied. The protein subunit from egg yolk was purified and hydrolyzed by Alcalase and Flavorase step by step. The results showed that the best ratio of enzyme concentration was 0.8% for Alcalase, and 0.4% for Flavorase to hydrolyzed 10% yolk solution. The hydrolytic time of the two enzymes was 2h respectively. Then the solution was incubated for 4h at 55°C while rotating at 60 r./min. To evaluate the hydrolysate, both the degrees of hydrolysis (DH) and the yields of the polypeptides were taken into consideration. The optimum ratios of enzyme and hydrolytic time were 2.43 and 1.14 respectively, and the optimum pH was 6.64. The optimized DH was 13.233%, and peptide yield was up to 45.573mg/ml.
Research into the Characteristics of Slewing Hydraulic System on Truck Crane
Authors: Xie Hai Bo , Liu Jian , Yang Hua Yong , Zhen Yu , Zhang Jin
Published: August 2011

The domestic 25-ton truck crane has the problems of high system pressure during steady slewing and great hydraulic impact when slewing motion starts and brakes. So the simulation model of the slewing hydraulic system and the core hydraulic components was constructed by AMESim. The flow areas of throttling grooves on the valve rod of the directional control valve were calculated by Matlab and converted into text files, which were imported into the simulation model. To get the load parameters of slewing system in different work conditions, an experiment on real truck crane was performed. Then the problem work conditions recurred in the simulation, which showed the veracity of the simulation model. Based on the simulation model an improving method was presented and simulated and the simulation results showed that through the improving method, the system pressure and the hydraulic impact could be efficiently reduced.
An Improved Design of Stochastic Halftoning without Error Diffusion for Raster Image Processor
Authors: Duan Hua Wei , Chen Guang Xue
Published: August 2011

The performance of modern printing machine depends heavily upon the raster image processor (RIP) whereof it is equipped with. The conventional digital halftoning technology used in RIP is characterized as error diffusion, which is suitable for imaging machines with low resolutions, often resulting in correlated artifacts and transient edges. We report an innovative stochastic halftoning method without error diffusion for RIP by using an optimized random number generator (RNG). The RIP system we proposed has simple computation and stochastic features of ink spots. This research is supportive of enhancing raster image quality oriented to printing machines with high physical resolutions.
Realization of QoS Control Strategies in the next Generation Network on the Basis of Differentiated Service Model and Priority of Inter-Frame
Authors: Du Xiao Dan , Hu Qing , Yu Hong , Du Yu Ming , Qiao Ying
Published: August 2011

With the development of networks and wideband technology, Next Generation Network (NGN) evolves into integrated transmission network of the multimedia information which including data, voice, image, the real-time tasks, etc. The traditional IP network provides only "best-effort" service and cannot meet the needs of multi-media applications and the different demands of a variety of users for network transmission quality. On the basis of a detailed analysis to Differentiated service (DiffServ) model and the characteristics of MPEG-4 encoding, the QoS control strategy of video streaming in NGN is proposed. That is a QoS control strategy which uses priority of Inter-Frame combining with DiffServ model in network congestion. Simulation and testing results show that the strategy can improve the transmission quality of the video stream effectively in the case of limited bandwidth.
Flexible Polishing Machine with Dual Grinding Heads for Aeroengine Blade and Blisk
Authors: Duan Ji Hao , Shi Yao Yao , Lin Xiao Jun , Dong Ting
Published: August 2011

The blade and blisk manufacturing includes polishing process when the surface roughness and size requirement of profile are disqualified after milling process. This polishing process is mainly carried out manually by skilled workers or NC machines. However, the existing polishing technology always leads to surface quality instability and inconsistency because of the complex free-form surface of blade and blisk. Therefore, in this paper, based on the research of polishing requirements and methods of blade and blisk, an automatic 6-axis polishing machine was proposed in order to enhance surface quality. And then, a polishing mechanism was designed using flexible technique to make the polishing tool accommodate surface waviness which was produced in milling process. In addition, the working principle and control method of flexible polishing mechanism were studied. Finally, the polishing test results of blade and blisk showed that the profile error was about 0.06mm and the surface roughness was less than Ra0.4 after automatic polishing. Compared with the manual polishing process, the automatic polishing technology not only increased the polishing efficiency and quality stability, but also reduced labor intensity largely.
Evaluation of Typical Asphalt Pavement Structure Performance of Chang-Ji Freeway
Authors: Zhang Ying Xue , Liu Zhao Hui , Li Ben Peng
Published: August 2011

Typical asphalt pavement structure of freeway integrates the advantages of experience method and theory method. It is the pavement structure combinating of different regions pavement projects experience which considers the factors of natural conditions, vehicle load, material supply, construction technique and maintenance operations and so on. This paper contains site detection and evaluation of the performance of 8 kinds of asphalt pavement structure testing roads of Chang-Ji freeway in Hunan Province, using five indicators of rebound deflection, flatness, friction coefficient, structure depth and seep coefficient and so on. We carry on tracking observation about the pavement’s performance for 2 years continuously. The results showed that the typical asphalt pavement structure testing sections of Chang-Ji freeway have been built successfully and pavement performance is good.
Analysis of the Main Parameters in the Chemical Mechanical Polishing Process
Authors: Yang Xiang Dong , Wei Xin , Xie Xiao Zhu , Chen Zhuo , Zou Wei Bo
Published: August 2011

This paper studies the chemical mechanical polishing (CMP) of the wafer's material such as stainless steel, monocrystalline silicon etc, and analyzes how the technological parameters’ impact on the final wafer’s surface material removal rate, surface quality and surface damage like the polishing pad’s speed and the wafer speed, polishing pressure and polishing time.The results show that: when the difference between the polishing pad's rotation speed and the wafer's rotation speed is small and their directions are the same , then the material removal rate of the wafer is larger.when the polishing pressure is selected between 5 to 6.5 kPa, the wafer surface's damage is smaller.The polishing time also play a very important role and affect the surface quality and surface damage of the wafer after polishing.
The Kinetics of Austenization Process of T91 Ferritic Heat-Resistant Steel
Authors: Zhang Li Fang , Liu Yong Chang
Published: August 2011

By fitting the calculated transformed fraction according to developed phase-transformation model to the experimental data obtained by differential dilatometry, the kinetic characteristics of the austenitization process in T91 steels have been investigated. According to the kinetic parameters fitted, we recognize that the nucleation and growth of austenite grain are mainly controlled by the diffusion of carbon in ferritic and austenite respectively. In addition, by increasing the diffusion active energy of carbon in austenite, carbides hinder the motion of interface and thus refine austenite grain.
Study on the Properties of Ground Limestone-High Alumina Cement Gelation System
Authors: Xiao Jia , Gou Cheng Fu , Xu Cai Yun , Xing Hao , Jin Yong Gang
Published: August 2011

Effects of various amounts of ground limestone on the setting time, fluidity and compressive strength of high alumina cement were described in this paper. Microstructure analyses were performed by SEM. The results indicate that the initial setting time, the final setting time, the fluidity and the compressive strength of the pastes increase first and decrease later with the ground limestone content increasing, all of which reach the maximum when the ground limestone content is 3%. Meanwhile, an increase of the fineness of the ground limestone produces a shorter setting time, the fluidity of the pastes increases when the content of the ground limestone increases, and the compressive strength of the hardened pastes increases with the ground limestone content increasing and decreases with water-binder ratio increasing. The 28d strength of the pure high alumina cement paste is lower than the 3d strength, appearing the strength shrinkage, which can be improved by a proper addition of the ground limestone.
Research of Robust Adaptive Fuzzy Control in Manipulator
Authors: Li Hong Lin , Zhao Peng Bing
Published: August 2011

There are friction characteristics, random disturbance, load variation and other nonlinear influencing factors in the multi-joint manipulator system generally. According to the problem that the traditional PID and fuzzy control are difficult to achieve rapid and high-precision control for this kind of system, a kind of robust adaptive fuzzy controller was designed based on fuzzy compensation under the circumstances that the fuzzy information can be known and all the state variables can be measured. Simultaneously, in order to reduce the computational load of fuzzy approximation and improve the efficiency of mathematical operation, a method that distinguishing different disturbance compensatory terms and approximating each of them respectively was adopted. The simulation results show that the robust adaptive fuzzy controller based on fuzzy compensation can restrain friction, disturbance, load variation and other nonlinear influencing factors.
The Collision Avoidance Path Planning of K-Joint Automatic Welding Robot
Authors: Wang Tian Qi , Li Liang Yu , Gao Tie Jun , He Jun Jie
Published: August 2011

A four freedom robot able to carry out automatic welding of offshore platform is introduced in this paper. The kinematic design of the robot has been designed according to the welding seam feature of T/Y/K-joint. The path planning of T/Y and the obstacle avoidance technique are used to study the robot’s collision avoidance welding on K-joint. In the process of K-joint path planning, the geometrical method was adopted to study the welding torch’s posture in branch gap. And for ensuring the postural stability of robot, the robot posture of a series welding points in single branch pipe condition was adjusted gradually in K-joint condition. The automatic welding process of K-joint was simulated in Solidworks. The result shows that the method could satisfy the collision avoidance requirement in the K-joint welding project.
Vertical Load Analysis of the Lifting Systems for Forging Manipulator during the Forging Process
Authors: Zhou Hua , Hou Jiao Yi
Published: August 2011

Holding the work piece for the forging press is the main task of the forging manipulator, and it is recognized as one of industry’s most arduous tasks. To ensure the safety of the manipulator mechanism, the resistance force exerted on the clamp must be minimized [1]. This paper focuses on the vertical load analysis of lifting systems for the forging manipulator when it works in cooperation with the forging press. First the equivalent stiffness model of the work piece is presented and the loads of the lifting systems are derived. Then the hydraulic circuits of the front and the rear lifting systems are investigated. Finally, the whole forging process is analyzed to study the relationship between the tracking error of the lifting systems and the resistance force on them. Simulation of one typical forging process shows that the cause of resistance force on the lifting system is the displacement tracking error.
Position Error Research of Multi-Legged Walking Robots with Hand-Foot-Integration Function
Authors: Zou Jing Chao , Wang Liang Wen , Tang Wei Gang , Zhang Duan Qin , Chen Wei Hong
Published: August 2011

Development of integrated hand-foot function will speed up the practical application of multi-legged robots. If the positions of each foothold, the driven joint variables and length of linkage bar in leg are inaccurate, the arms (swing leg) of the robot are likely to deviate from required positions. In this paper, through the calculation process of the multi-legged walking robot's arm path, we discussed the calculating problem of the arm's position accuracy under the condition that the errors of foothold positions, driven joint variables and leg's linkage bar length are given. Detailed calculation formulas are given, and the analysis process is illustrated by an example.
The Research of the PCB Location Based on Three Layers of MARK Point
Authors: Wu Hao , Zhang Xian Min , Kuang Yong Cong
Published: August 2011

In order to reduce the position error produced by single board assembly and partial uneven surface in automated optical inspection, a new position method based on three layers of MARK point is developed. the first layer is the whole board alignment which compensate the position error of the PCB loading process, the second layer is the single board alignment which compensate the position error of the single board assembly, the last layer is the partial FOV(field of view) alignment which compensate the position error of the partial uneven surface. The experiment result proved the proposed position method improved the position accuracy obviously.
An Improved Pedestrian Detection Method Based on Adaboost and Performance Analysis
Authors: Zhang Yan Xi , Gao Xiang Dong
Published: August 2011

Pedestrian detection, which has a wide application in surveillance, advanced robotics, and especially intelligent vehicles, is an important area in computer vision. This paper applies a detection approach based on improved Adaboost algorithm. We use a dataset to train the weak classifiers (with different numbers) to cascade to be strong classifiers, in which we employ optimized strategy of sample weight adjustment to reduce the over-fit. After constructing a strong classifier, we apply different scale of sliding widow to shift and calculate the corresponding features to classify them as pedestrians or non-pedestrians. The experiments show that different numbers of weak classifiers layer and different scale of sliding windows can give different performance in detecting.
The Research on Camera Axis Perpendicular to the Target Surface and Method to Confirm its Position in Space
Authors: Gao Shang , Zhu Xing Long , Zhou Ji Ping , Zhao Xin , Yin Nan
Published: August 2011

Confirming the position in space of the camera axis and it perpendicular to the target surface has important significance for simplifying the camera calibration in interior parameters. This article conducted a study on this issue. First, it establishes the relationship of the world coordinate system, the target coordinate system, the camera coordinate system and the image coordinate system. The necessary camera calibration in external parameters and internal parameters are confirmed. Second, the first target coordinate system is adjusted to the same position with the world coordinate system. The adjustment principle of the camera axis perpendicular to the target column end surface is proposed. Namely, whether the camera axis perpendicular to the first target column end surface or not is confirmed by the CCD image edge whether it’s round or not. As the world coordinate system is based on coordinate measuring machines, so the world coordinate of the first target column end surface circle is obtained. Then the second target is placed in between the camera and the first target, and the second target coordinate system is adjusted to the same position with the world coordinate system, and it is adjusted to the same coordinate (except y direction) with the first target column end surface circle’s coordinates. So the images of the first target and the second target column end surface circle in the CCD surely are circles. Third, the method to seek for the camera axis is put forward, namely if the circles of the first target and the second target column end surface circle in the CCD are not concentric, then it shows the optical axis and the joined axis of the first and second target face round are not concentric. By adjusting the CCD camera's position, until the circles of the first target and the second target column end surface circle in the CCD are concentric, such the camera axis can be represented by the joined axis of the first and second target end round. Simultaneously the target circle's center reflects the deviation on CCD coordinate between the optical center and the CCD center. Finally, the camera internal parameters are expressed by the related parameters.
A 3D Reconstruction Framework from Image Sequences Based on Point and Line Features
Authors: Deng Bao Song , Yu Rong Huan , Deng Tie Qing , Wu Ling Da
Published: August 2011

A novel three dimensional reconstruction framework from wide baseline images was proposed based on point and line features. After detecting and matching features, the relations between discrete images are computed and refined according to multi-view geometric constraints, and both structure of the scene and motion of cameras are retrieved, where we employ a procedure of Euclidean reconstruction based on approximate camera internal parameters and buddle adjustments. Based on retrieved motion and correspondence of line features, a 3D line reconstruction scheme was put forward to assist us in gaining regular structure and topology of the scene. In virtue of some manual interactions, mesh models of the scene came into being, and a rectification method for perspective images was used to acquiring texture patches. Finally, an interactive modeling prototype system from multiple images is designed and implemented. Real scenes and augmented reality applications demonstrate the feasibility, correctness and accuracy of our framework.
Study on Low Application Temperature Process of Three Layer Polyethylene Coating
Authors: Shao Huai Qi , Guo Xiao Yan , Jiang Tao , Zhang Qi Bin
Published: August 2011

The mechanical property of X80 longitudinally welded pipe, as part pipeline for second west-east natural gas transmission pipeline project, is disadvantageously affected by normal coating process of three layer polyethylene coating(3LPE). The low application temperature process of three layer polyethylene coating coated at 185~195°C was studied to meet the requirement of the coating temperature of X80 longitudinally welded pipe. The suitable epoxy powders and coating process were determined by evaluating coating properties of varied epoxy powders. The properties of 3LPE, which was coated by using suitable low temperature cured epoxy powder at temperature of 185~195°C, were nearly same to the ones of 3LPE at the normal coating temperature (200~230°C) and meet the requirement of external anti-corrosion properties of X80 longitudinally welded pipe. According to the results, a criteria was provided to CNPC and applied to project of second west-east natural gas transmission pipeline.
Characterization of Rotating Cavitation in a High Speed Inducer of Liquid Rocket Engine
Authors: Tang Fei , Wen Li Jia
Published: August 2011

Rotating cavitation is one of the most important problems in the development of modern high performance rocket pump inducers. In this paper, a numerical simulation of rotating cavitation phenomenon in a 2D blade cascade of liquid rocket engine inducer was carried out using a mixture model based on Rayleigh-Plesset equation. The purpose is to investigate the characterization of rotating cavitation in a high speed inducer. The results show that when sub-synchronous rotating cavitation occurs, the speed for the length of the blade surface cavitation is lower than the speed frequency of rotation shaft with the same direction. The external aspect is that the pressure at the upstream of blades changes synchronous. Thus, the generation of sub-synchronous rotating cavitation is closely related to the changes of flow angel which caused by the flow fluctuations. Hence, elimination of the flow rate redistribution among the flow channel can effectively suppress the occurrence of this phenomenon.
Computer-Aided Design (CAD) and Environmental Art Design
Authors: Ma Lan
Published: August 2011

Computer-aided design (CAD) poses a brand new change of environmental art design from concept to skills. Nowadays, computer operation is a must for environmental art design, and no one can ignore such a powerful trend. This is transition period from traditional manual design mode to advanced computer design mode, and now we are standing on top of this new start point. CAD has fully performed its charm and become an indispensable tool in the field of the environmental creative art design. Mastering relevant software has become an essential skill for designers. However they often feel lost in current complex computer software, or even when they have conquered software technology difficulties, still trapped into a hard-pressed embarrassment to combine design with ideas. This dissertation starts from CAD definition, discusses CAD development and its own characteristics, and further on CAD applications in environment art design, main types and functions in current CAD software. The end of this article also gives an outlook on future effects and scheme a better vision for CAD in environmental design.