bluuebunny/crossref_metadata_2025 huggingface dataset:
Mathematical Model for the Effect of Dynamic Parameter Posed on Free Floating Space Manipulator’s Kinematic Accuracy
Authors: Tan Yue Sheng
Published: March 2011

Aiming at kinematic accuracy and its’ error sources of a free floating space robot, a mathematical kinematic error model based on the concept of virtual manipulator and screw theory is proposed in this paper for a free-floating space robot. Based on screw theory, structural parameters in the form of motion screw and their error expressions derived from various error sources are deduced. The effect of mass error, CM (Center of Mass) error and structural parameter error on the kinematic accuracy of the free-floating space manipulator is analyzed. A simulation is demonstrated for verifying the correctness of the kinematic error model and the effect of various error sources on the free-floating space robot. The error model and the result deriving from analyzing are vital for studying the kinematic accuracy of the space manipulator when it is under a free-floating mode, and for controlling and assigning various errors when a space robot is developed.
Hydrogen Dilution Influence on the SIC Films Optical and Micro-Structural Properties as the Window Layer of P-i-n Solar Cell
Authors: Xu Bao Yu , Yang Hui Dong , Huang Bo , Shi Jun Dai
Published: March 2011

The SiC thin films as the window layer was prepared by PECVD technology in this article, investigated the influence of hydrogen dilution on the optical and micro-structural properties of SiC thin films, Analyzed optical band-gap，deposition rate and surface morphology under different hydrogen dilution ratio, found the optimal growth craft under the same conditions. The results showed that the optical band-gap of the window layer achieved the widest 2.2ev when hydrogen dilution rate was 6.25.
Band Gaps of Two-Dimensional Square-Lattice Photonic Crystal with Button-Shaped Dielectric Rods
Authors: Du S.X. , He X. D. , Liu B. , Li S. J. , Zhang Z.M. , Li S.
Published: March 2011

In this paper, a new structure of two-dimensional (2D) square-lattice photonic crystal (SLPC) with button-shaped dielectric rods (BSDRs) is designed, and the properties of band gaps are analyzed by Plane Wave Expansion Method (PWM). The optimal samples that possess the width of absolute band gap are obtained by scanning the three parameters: the radius of large circular R in button mark, the ratio of the radius of small circular to the radius of large circular r/R, and the rotating angle of button mark Ө. It is shown that when r/R=0.485, R=0.406um, and Ө =750, the largest absolute band gap of 0.0406 (ωa/2πc) exists for normalized frequencies in the range 0.7501 to 0.7910 (ωa/2πc). Besides，we can get at most five absolute band gaps when r/R=0.485, R=0.406um, and Ө =600.
Research on Video Information Acquisition Module of OV7620
Authors: Xu Lei , Lu Wei
Published: March 2011

In order to meet real-time and quick requirements for video information acquiring and processing, this paper introduces a hardware platform based on Altera's Cyclone series EP1C12Q240C8, to descript the driving timing for CMOS image sensor OV7620 with Verilog HDL language to acquire video information. The system uses SCCB programming model, establishes communication between FPGA chip and CMOS image sensor to achieve the control and acquisition of the signal. In order to achieve operational requirements in different environments and needs, the corresponding registers and the controller are set within CMOS image sensor. Experimental results show that the control of the CMOS image sensor OV7620 flexibly provides a stable and reliable source of raw information for video monitor, industrial applications such as on-site monitoring.
A Security Method for Multi-Sensor Fused Image
Authors: Huang Feng , Pan Zhong Ming
Published: March 2011

Sensors are used more and more widely today. It can get valuable images through multi-sensor fusion technology. The paper designs an image security method for multi-sensor fused image. It includes keys generation, permutation, diffusion and decryption. Using six decimal numbers it can get three keys in keys generation part. The process of permutation used a new chaotic map to shuffle positions of image pixels. The process of diffusion used classic chaotic map to flat the histogram of the ciphered image. Decryption process is the reverse process of encryption process. The results prove its validity. It also show it can be used in real-time information protect for fused image.
Crystal Growth, Optical Spectra and Thermal Properties of Na2Ni(SO4)2·4H2O Crystal
Authors: Zhuang Rong Rong , He Yi Zong , Fang Yu Hong
Published: March 2011

Na2Ni(SO4)2·4H2O crystal (NNSH) size up to 12mm×10mm×8mm have been grown by heating the solution gradually. The structure of crystal was determined by X-ray diffraction method. The transmission spectra with strong absortpion band at visible and infrared region were measured by using UV-VIS ultraviolet spectrophotometer. Absorption cross-sections of crystal at 344nm and 640nm were evaluated as 4.380×10-18cm2and 3.63×10-18cm-2,respectively. NNSH was stable at high temperature, for the dehydration temperature of the crystal was determined to be 132.6 °C by thermogravimetric measurement. It was shown that NNSH had strong absorption at visible or infrared region and high thermal stability that may render it to be a filter material as to obtain more pure ultra-violet spectrograph and be accessible in high temperature environment.
A New Modeling on Information Transmission of Weak Electrical Signals in the Nutrition Growth of Plant
Authors: Wang Lan Zhou , Li Qiao
Published: March 2011

y=f(m,t)c+g(m,t)for the first time. A mechanism on the information transmission of the nutrition growth in plants was discussed by the math language. The bark and timber at a stem of plants could be derived from phloem and xylem cells respectively because the wave period of electric signals’ cin cambium cells was rather short and needed to transfer the growth information of cells to the circumference rapidly. It was why the wave period of electric signals at the cambium of plants was shorter than the phloem and xylem. Only positive amplitude value of electric signals of the xylem was bigger than the phloem and cambium, which expressed the needed more energies for the elongated growth up of plants. An importance is that the discovery in this paper may find out the character preferences for constructing a system of the intelligent control growth by feedback information at the transmission of the signals in plants or crops, and to realize the energy saving and pollutant abating to environments.
Orthogonal Polarization Spectral Imaging in Microcirculation
Authors: Wang Hong , Cui Jan Guo , Liu Yang Yang , Chen Guo Ming , Liu Sheng Ping
Published: March 2011

The microcirculation plays a crucial role in the interaction between blood and tissues in physiological pathophysiological pharmacological and clinical states. Despite its significant role in numerous diseases including, hypertension diabetes, sepsis or multiple organ failure, visible and near-infrared light, offer a window into human and animal tissues due to reduced scattering and absorption. We review orthogonal polarization spectral (OPS) imaging method for direct visualization and quantitative assessment of human microcirculation at the bedside are limited. OPS imaging is a relatively new noninvasive method for assessment of human microcirculation without using fluorescent dyes. Recent clinical studies using OPS imaging in various pathological states have shown a wide spectrum of different clinical applications with evident impact on the diagnosis, treatment or prognosis assessment. Thus, there is a great effort to validate OPS imaging for various clinical purposes. The principles of OPS imaging, validation studies, its advantages, limitations, methods of quantitative assessment and current experience in clinical practice are also discussed.
The Propagation Losses of Cold Deposited Zinc Sulfide Waveguides
Authors: Salleh Saafie , Dalimin M.N. , Rutt Harvey N.
Published: March 2011

Zinc sulfide (ZnS) waveguides with the thickness of 0.5 μm have been deposited onto oxidized silicon wafer substrates at cold temperature (Tcold = –50°C) and ambient temperature (Tambient = 25°C) by thermal evaporation technique. The propagation losses of ZnS waveguides were determined by a scattering detection method. The propagation losses of cold deposited ZnS waveguide were 20.41, 11.35, 3.51 and 2.30 dB/cm measured the wavelengths of 633, 986, 1305 and 1540 nm, respectively. Where as, the propagation losses of ambient deposited ZnS waveguide were 131.50, 47.99, 4.43 and 2.74 dB/cm measured the wavelengths of 633, 986, 1305 and 1540 nm, respectively. The propagation loss of the cold deposited ZnS waveguide was dominated by surface scattering whereas the propagation loss of the ambient deposited ZnS waveguide was dominated by bulk scattering.
Applying Template Method Pattern to Developing Electrochemical Workstation
Authors: Li Bo , Ma Zhi Qing , Wang Jian Yi , Guan Yi Ran , Liu Xian Yi , Yang Gui Fu
Published: March 2011

This paper presents a feasible way to develop electrochemical workstation by using Template Method pattern. With this design pattern, software designers can separate electrochemical technique into specific steps for system analyzing, and also provide a uniform external interface when invoking different kinds of electrochemical technique.
Research on Milling Spiral Bevel Gear Using CТС Machine Tool
Authors: Du Yan Xia , Lü Bao Zhan , Bin Feng Guo
Published: March 2011

From the NC machining principle of spiral bevel gear, the motion relationship of machine tool, cutter and workpiece during machining spiral bevel gear was analyzed. Based on the machine coordinate system, the tooth surface equation and the cone equation of cutting edges of spiral bevel gear were put forward. 3D solid model of spiral bevel gear was constructed using Pro/E Wildfire2.0 software. The NC milling simulation was carried out by the VERICUT software, and at the same time, the experiment was researched. Simulation and experimental results show that the spiral bevel gear can adopt the method of CNC machining, and can ensure the high quality, especially for single or small batch production.
Realization of Wireless Communication Card Based on UWB for Industrial Internet of Things
Authors: Wang Jun , Mei Zhan , Wei Li Feng
Published: March 2011

For further development and building a solid foundation of industrial Internet of things, a wireless communication card (WCC) based on UWB used in industrial Internet of Things (IoT) is designed in the paper. The implementations of WCC are proposed and critical problem on software design is solved. It successfully solves the problem of communication with IO card. At the same time, it provides upgrade program form industrial control systems to industrial Internet of Things.
Research on Relationship between Residual Stress of Hole Cold Expansion and Process Parameter
Authors: Zhang Hong Shuang
Published: March 2011

The hole cold expansion is a well-known technique used to improve the fatigue life in mechanical structures. An approach named simulation experiment was used to establish the relationships between maximum residual stress and the process parameters in order to quantitatively understand residual stress status around the hole after expansion working. Firstly, Finite Element Method was employed to substitute the physical experiments to get the residual stress distribution of the hole of different expansion ratios, hole diameters and plate heights. Secondly, Excel software was used to obtain the trend curves of maximum residual compressive stress of different parameters. Then the equations of trend curves were obtained based on the least square principle. The results show that the simulation experiment approach is practical to implement and meet the actual accuracy need of engineering, and could establish the foundation for analysis of the fatigue life in mechanical structures.
Stochastic Excitation Model of Strip Rolling Mill
Authors: Xu Bao Yu , Liu Yi Lun , Wang Xu Dong , Dong Fang
Published: March 2011

The stochastic excitation power spectral density (PSD) model and ARMA time series model are established based on the stochastic rolling force acquisition data, which is processed into stationary, normal and zero mean from a aluminum hot strip tandem mill. Characteristics of rolling force ARMA time series models are discussed by means of random process theory. The rolling forces PSD function of facilitating engineering application is obtained by utilizing Levenberg-Marquardt combined with generalized global planning algorithm, and the stochastic excitation model is established. It provides the basis for the prediction of rolling force.
A Study on Orthogonal Experiments of YAG: Ce3+ Yellow Phosphor for White LED
Authors: Guan Rong Feng , Li Qin Qin , Li Shuai Mou
Published: March 2011

The YAG yellow phosphor was synthesized by Co-precipitation Method and its luminescent properties were characterized. The Orthogonal Experiment results that under laboratory conditions, the prepared phosphor luminous intensity reached at the maximum and the optical properties of compound as white up to the best with blue-chip, when calcinations temperature up to 1600°C, sintering time is 3h, the Ce3+content is 0.05.Therefore, the phosphor could provide a theoretical basis for the design and development of white LED with luminescent materials, promoting the practical of white LED.
Electronic Structures of Donor-Acceptor-Donor Trimer Codopants in Silicon
Authors: Kambara Nobuo , Kawanishi Hiroyuki
Published: March 2011

The total energies of donor-acceptor-donor D2A trimer codopants (D = As and Sb, A = B, Al, Ga, In and Tl) in Si and their electronic geometrically stable structures were studied using ab initio calculations in order to propose new dopants for the formation of ultra shallow junctions with high carrier concentrations in the source/drain regions. The results of the calculations indicated that the trimer codopants were formed in Si and were stable. The trimer codopants are also able to activate the inactive complexes As2V and Sb2V by codoping acceptor atoms that occupy vacant sites. In particular, As2Al, As2Ga, Sb2B and Sb2Ga resulted in both shallower donor levels and higher solid solubility compared to traditional single donor atoms such as As and Sb.
The Analysis and Research on Digital Holography Signal Based on Wavelet Theory
Authors: Wang Yu Tian , Wang Dong Sheng , Pan Wei Wei
Published: March 2011

When introduce the wavelet theory to filter the hologram and the reconstructed image in the digital holography, the noise of the reconstructed image is greatly reduced. In the off-axis digital holography, the zero-order wave is decreased dramatically when after a wavelet filter, at the same time, the speckle noise is also reduced, and it turns out that the resolution of the reconstruction image is improved greatly. The system launches the research thoroughly on the three-dimensional body digital holographic technology, from the theory to the application, from the simulation to the experiment, and has elaborated and analyzed each characteristic of three-dimensional body digital holographic technology. It proposes many kinds of improved effective method of three-dimensional body digital holographic restructuring information, and finally has effectively explored the three-dimensional body digital holographic technology application through the experiment.
Laser Cladding of a Ramp Thin Wall with a Variable
Authors: Wang Xu Yue , Guo H.R. , Xu Wen Ji , Guo Dong Ming , Wang L.J.
Published: March 2011

To reduce stair-step effect when layered forming samples using 2.5D slices, a geometric model with variable thickness slices was developed. Experiments were performed with varying of powder feed rate. Relationships between geometrical precision of samples formed by laser clad forming (LCF) and a variable of powder feed rate were investigated. While the variation of powder feed rate with a calculated step was approximately continuous, clad layers with height increasing approximately linearly along clad length were achieved. Clad height increased from 0.05 to 0.39 mm with powder feed rate varying from 0.5 to 2.5 g/min. Scanning paths were planned by simulating forming process of the ramp through Matlab program. Using the scanning path, a relatively smooth ramp thin wall of 316L stainless steel was formed with a slope angle 3.37° by the experimental validation.
Novel Remanufacturing Technology as an Alternative to Maintenance for Diesel Engine and its Benefit Analysis
Authors: Cai Zhi Hai , Zhang Ping , Liang Zhi Jie
Published: March 2011

To solve the maintaining shortcoming of diesel engine, the remanufacturing technology idea of diesel engines is put forward and discussed preliminary. Then it summarizes the difference and processing between remanufacturing and maintenance for diesel engine, and the technical measures that may bring about economic benefits for the enterprise. Then the application perspective of remanufacturing technology for equipment diesel engines was outlooked. Notable economy benefit will be gained prolonging the service life of diesel engine.
ForCES-Based Firewall with Stateful Packet Inspection
Authors: Dong Li Gang , Luo Feng , Wang Wei Ming , Chen Ke
Published: March 2011

In order to meet the extensibility and flexibility requirement of next generation network, ForCES working group of IETF proposes an architecture with the separation of Forwarding Element and Control Element. A firewall with ForCES architecture will have enough flexibility on security function extensibility. This paper not only designs the ForCES architecture of status package inspection firewall and related LFB (Logic Functional Block), but also implements a prototype system and carries out tests and analysis. The experiment result testifies the feasibility of ForCES specification and provides the important technical parameter for the ForCES security application.
Luminescence Dynamics and Structural Investigation of InGaN/GaN Multiple Quantum Well Light Emitting Diodes
Authors: Lee Zhen Sheng , Kong Ling Min , Feng Zhe Chuan , Li Gang , Tsai Hung Lin , Yang Jer Ren
Published: March 2011

Luminescence properties of blue emission InGaN/GaN multiple quantum well (MQW) have been studied by temperature dependent photoluminescence (PL), photoluminescence excitation (PLE) and time-resolved photoluminescence (TRPL) spectroscopic techniques. Two typical samples are studied, both consisting of five periods of InGaN wells with different indium compositions of 21% and 24%, respectively. According to the PL and PLE measurement results, large values of activation energy and Stokes’ shift are obtained. This indicates that higher Indium composition results in an increase of composition fluctuation in the InGaN MQW region, showing the stronger carrier localization effect. The lifetime at the low-energy side of the InGaN peaks is longer for higher indium composition, as expected from the larger Stokes shift.
Effect of Aggregate Size and Gradation on the Ceramsite Sound-Absorbing Materials
Authors: Luo Xiang Yu , Li Wen Fang , Jin Xue Li
Published: March 2011

In this paper, the effect of ceramsite aggregate size and gradation on the sound absorption and mechanical properties of the materials were studied and the relationship between material’s pore structure and its sound absorption were discussed. It can be found from the results that the sound absorption and mechanical properties of the ceramsite sound-absorbing materials increase with the content of the fine ceramsite increased due to the decrease of the median pore diameter of the ceramsite sound-absorbing materials where the improvement of the sound absorption at the high frequency band is more significant suggesting that fine pores have a better sound-absorbing effect for high-frequency noise. Higher effective porosity doesn’t mean better sound absorption, because materials with coarse pores have shorter internal routes for sound waves and less friction during sound waves passing through pores, which conversely decreases the material’s sound absorption. Ceramsite with higher internal porosity and more uniform pore diameter distribution can produce materials with better sound absorption.
The Timber Supply Chain Risks Assessment Based on Weighing with Rough Set and Fuzzy Comprehensive Assessment
Authors: Wang Zhong Wei , Kang Yi Xiong
Published: March 2011

This paper studied the timber supply chain risks assessment. Firstly we established the risks assessment index system according to the characteristics of timber supply chain, and then we formulated the method of weighing indexes based on rough set theory, and then we established the supply chain risks assessment models with fuzzy comprehensive theory to judge the risks level. By case analysis, we draw the conclusion that the factors of production and processing and the factors of sales make grater impact on the timber supply chain, while the factors of natural and the factors of reverse recycling make smaller impact, and the risks of other factors are moderate.
Conventional Plasticity Constitutive Model for Shape Memory Alloys
Authors: Li Hai Tao , Peng Xiang He
Published: March 2011

A two-phase constitutive model for shape memory alloys (SMAs) is proposed based on the fact that SMAs is dynamically composed of austenite and martensite. The behavior of SMAs is regarded as the dynamic combination of the individual behavior of each phase. This model can describe the main characteristics of SMAs, such as pseudoelasticity and shape memory effect. The corresponding numerical algorithm was also developed to describe the main features of shape memory alloy Au-47.5at.%Cd.
Effect of Equilibrium Moisture Contents on Insulating Performance of Autoclaved Aerated Concrete Blocks
Authors: Jin Xue Li , Luo Xiang Yu , Meng Qing Lin
Published: March 2011

In this paper, a research was performed which considers the material characteristics of autoclaved aerated concrete (AAC) blocks and the weather characteristics in Pearl River Delta region. The AAC blocks laws of absorption and desorption and its thermal conductivity under different equilibrium moistures were measured. The experimental results show that equilibrium moisture content (EMC)is 6.27% for AAC blocks with a B07 density in hot and humid areas in the Pearl River Delta region including the city of Guangzhou, and the correction coefficient of the thermal conductivity is 1.5.
Application of Over-Sample Policy and Rotated Angle Invariability of Radial Sampling Points in the Isaf Reconstruction Algorithm
Authors: Wang Gong Ming , Zhang Fa , Chu Qi , Liu Zhi Yong
Published: March 2011

ISAF (icosahedral symmetry-adapted functions) algorithm is the new high-resolution algorithm of icosahedral macromolecules. But its running speed is very slow because of the time-consuming operations of mapping sampling points into 3D space. In this paper, a new sampling method is proposed to improve the running speed of this stage. First of all, the angle corresponding to one pixel arc in the maximum Fourier ring is taken as the sampling angle and the same angle sampling is applied in every rings. After that, the sampling points in radius one ring are mapped into 3D space. Finally, the 3D spatial positions of radial sampling points in other rings can be deduced quickly according to the rotate angle invariability of radial sampling points. The HBV (Hepatitis B Virus) Cryo-electron microscopy images are used for validating this strategy. At the high resolution of 6.64 angstrom, the local speedup in the stage of mapping sampling points reaches to 50, and the overall speedup can be improved in an order of magnitude. The overall speedup increases with the increasement number of EM images and the improvement of target resolution.
A Simple Password-Based Authenticated Key Agreement Protocol
Authors: Lee Yung Cheng
Published: March 2011

The authenticated key agreement protocols are widely used mechanisms for users to negotiate session keys and authenticate each other. Until now, there are many authenticated key agreement protocols proposed. However, many of them suffer from various attacks such as guessing attack, replay attack, impersonate attack, etc. In this paper, we propose a simple password-based authenticated key agreement protocol to solve these problems. The proposed protocol not only provides forward and backward secrecy, but also can resist replay attack, modification attack, and password guessing attack. Moreover, the computation cost of the protocol is very low.
A Demodulation Scheme for High-Sensitivity Temperature Sensing Based on Long Period Fiber Grating
Authors: Zhao Hong Xia , Wei Li , Ding Zhi Qun
Published: March 2011

Long Period Fiber Grating (LPFG) sensors have wide range of potential applications; low-cost and high-sensitivity demodulation technology is the key of its practical applications. In this paper, an interferometer is comprised of an all-fiber loop mirror and two identical LPFGs, a tunable F-P filter is used to perform wavelength scanning one of the interference peaks, two negative pulse interval formed by signal light in the drive signal period are measured by means of detector and oscilloscope to realize signal demodulation. This demodulation system was used to detect the temperature parameter. The results showed that the sensing sensitivity of this system was demonstrated to be 0.08349 ms/°C, experimentally, which was 2.3 times higher than a single LPFG using the same demodulation technology.
Sensitivity Analysis of CFST Frame Sidesway Based on Correlation
Authors: Pan Jian Rong , Wang Zhan
Published: March 2011

This paper focused on sensitivity analysis about CFST frame sidesway (concrete-filled steel tubular) according to mutual relationships between variables. Two specimens were tested by incremental loading and cyclic loading. The finite element package ANSYS was used to study the nonlinear behavior of such specimens. The model was validated by comparing the computed values with experimental results. The probabilistic sensitivity analysis of CFST frame sidesway was carried out based on correlations in variables of the frame sidesway. Interlayer spacing was important sensitive parameter for frame sidesway. Good agreement between sensitivity analysis and mechanical formulation of lateral rigidity was observed.
Effect of Er2O3 on the Microstructure and Electrical Properties of (Er, Ta)-Doped Tio2 Capacitor-Varistor Ceramics
Authors: Wang Tian Guo , Qin Qun , Zhou Dong Jian
Published: March 2011

TiO2-based capacitor-varistor ceramics doped with Er2O3 were prepared and the microstructures and nonlinear electrical properties were investigated. The results show that there exist second phase Er2TiO3 on the surface of TiO2 grains. The grain size was found to decrease with increasing Er2O3 content. The addition of rare earth oxide Er2O3 leads to increase the nonlinear coefficient and the breakdown voltage. It was found that the nonlinear coefficient presents a peak of α = 4.5 for the sample doped with 1.1 mol% Er2O3, which isconsistent with the highest grain boundary in the composition. In order to illustrate the role of grain boundary barriers for TiO2-Ta2O5-Er2O3 varistors, a grian boundary defect barrier model was introduced.
Solar Cell Fabrication by Wet Etching Combined with Ultrasonic Vibration for Multicrystalline Silicon
Authors: Wu Li Qun , Chao Yan , Luo Xiao Lu
Published: March 2011

With the development of economy and society, more and more energy is needed to meet the requirement of industries and social life. It is necessary to find new types of energy that is clear, high effective and non-polluted. Although wet etching is widely used in industries to prepare the silicon surface texture, the etching process is stochastic and the influence light trapping. Many efforts have been made such as adjusting the proportion of different acids, to improve the quality of silicon surface by wet etching, the result does not meet the ideal requirement by now. In this paper, a new approach is presented to prepare the surface texturing. By combining wet etching and ultrasonic vibration, the sodium or acid molecular motion can be controlled, and the pyramid structure in silicon surface can be made regular.
Studies on Security Communications of Embedded Devices
Authors: Yan Tian Yun , Xu Kai Kuo , Wei Min , He Jia
Published: March 2011

The theory and technology of cryptography including the block cipher, stream cipher and public-key cryptosystem. The usual cryptographic algorithms, such as DES, RSA, AES and message digest algorithms are discussed. Basing on these studies, a design of secure communication is presented. It combines the data encryption with the authentication, can be applied to principal and subordinate system. It can provide a reliable protection for the secure communications for embedded devices. Finally, the core source code is shown.
Design of Control and Display System of Infrared Cooker Based on TMP86FH09ANG and CY8C21534
Authors: Wang Yong Hua , Du Jian Hong , Yang Jian
Published: March 2011

By using low-power Toshiba microcomputer TMP86FH09ANG and capacitive touch-detecting chip CY8C21534, a control and display system of infrared cooker was designed. Its input and output are touch-sensitive buttons and LED respectively. The chip CY8C21534 can sense any changes of the capacitance of the touch-sensitive buttons. According to keyboard inputs, the corresponding operations such as power on/off, plate selection, fire adjustment, timing and child locker can be realized. The diagram of hardware circuit is presented in detail, and the software functions are introduced. This design can be reference to the development of related products.
The Research of AD-HOC Network Bandwidth Control Distribution Mechanism
Authors: Li Hong Juan , Kang Jin Cui , Dong Qian , He Dong Bin
Published: March 2011

Ad Hoc network is a novel type of mobile computer network, Its own distinctive quality entrusts with its huge prospects for development. This paper presents a TM program, and thus to determine the proportion of each data stream in multi-hop ad hoc wireless networks accounts for the channel time. At the same time, TM program based on a proposed multi-hop wireless data flow algorithm for fair bandwidth allocation.
An Improved Range-Based Time Synchronization Protocol in WSN
Authors: Li Zhe Tao , Pei Tingrui , Wei Ye Hua
Published: March 2011

An improved method about range-based time synchronization (RTS) was proposed in this paper. By exploiting the synchronization redundancy between nodes, we proposed head-end modification and end-end modification to enhance time synchronization precision. Simulation results show improved RTS outperforms in terms of accuracy than RTS.
Path Planning Methods of Mobile Robot Based on Soft Computing Technique
Authors: Zhang Hong Min
Published: March 2011

Path planning is one of the most important and challenging problems of mobile robot. It is one of the keys that will make the mobile robots fully autonomous. In this paper, we summarized the application of soft computing approaches in path planning for mobile robot. Finally the future works of path planning for mobile robots are prospected.
Modeling and Simulation of Direct Force Control for PMLSM
Authors: Wang Xu Dong , Feng Hai Chao , Xu Xiao Zhuo , Xu Bao Yu
Published: March 2011

Direct force control (DFC) with the advantages of simple structure, fast force response, superior control performance, is developed from direct torque control (DTC). So, it is attracting more attention, increasingly becoming a research hot in the control field. It is a valuable research to improve the operation stability of PMLSM by the direct force control. In this paper, based on DFC principle analysis, the force control and flux control theory of DFC is studied according to the mathematical model of PMLSM. The structure and implementation method of DFC is analyzed, and then the DFC system simulation model for PMLSM is built by Matlab/Simulink. The simulation results show the feasibility of the simulation model, with good static and dynamic performance.
Stochastic Stability of Hot Strip Rolling Mill Rolls
Authors: Xu Bao Yu , Liu Yi Lun , Wang Xu Dong , Wang Yu Qing
Published: March 2011

A two dimensional stochastic nonlinear dynamical model of rolls is presented considering the stochastic factor of the rolling force. The Hamilton function is also described as one dimension diffusion process by using stochastic average method, the singular boundary theory was taken for analyzing the global stochastic stability of the system, and the system’s stochastic stability is researched by solving the Fokker-Planck-Kolmogorov (FPK) equation. The results show that the generalized energy H in the range of 0.02 to 0.4, the system’s response has the minimum transition probability density, and the system state is not easy to change, therefore the system generalized energy H should be to limit in this range in the design and operation of the rolling mill.
Study on the Multiple Voltage Source Inverter for Grid-Connected Large-Scale Wind Energy Conversion System
Authors: Mao Jing Feng , Wu Guo Qing , Wu Ai Hua , Cao Yang , Yang Kun
Published: March 2011

This paper proposes a novel grid-connected multiple voltage source inverter (VSI) for large-scale wind energy conversion system (WECS) applications. Firstly, the typical configuration, operation principle and mathematical modeling of the direct-drive grid-connected WECS are analyzed in brief. Then, a suitable topology of the grid-connected multiple VSI composed of two six-pulse inverters, two separate zig-zag transformers and a dc-link capacitor is presented. In order to reduce numbers of commutations and to increase dc-link voltage utilization ratio of the proposed grid-connected multiple VSI, a quasi twelve-pulse phase-shift PAM switching strategy is demonstrated. Finally, a simulation test system is set up by using MATLAB/SIMULINK, and the results of simulation validate the effectiveness of the proposed grid-connected multiple VSI.
Radiative Transitions and Optical Behaviors in Tm3+ Doped Mixed Alkali/Alkaline-Earth Modified Heavy-Metal Gallate Glasses
Authors: Zhao Xin , Zhang Jie , Lu Man Man , Lin Hai
Published: March 2011

Efficient ~1.48 and ~1.8mm infrared emissions have been recorded in Tm3+doped mixed alkali/alkaline-earth modified heavy-metal gallate glasses (LKBPBG) with low phonon energy under 793nm excitation. Judd-Ofelt parameters W2(4.34´10-20cm2), W4(9.74´10-21cm2) and W6(1.00´10-20cm2) indicate a higher asymmetric and stronger covalent environment in the glass material. The spontaneous transition probability and maximum emission cross-section of3H4→3F4transition are derived to be 283s-1and 2.90´10-21cm2. The maximum emission cross-section of3F4→3H6transition is calculated to be 6.82´10-21cm2, and the ideal net gain coefficients at 1.675 (U-band edge) and 1.872mm are given to be 0.56 and 3.51dB/cm, respectively, as the population inversion equals 1.0, which provide a theoretical anticipation in developing U-band amplifiers and eye-safe medical lasers.
Research on Magnet Excitation and Image Processing Used in Visual Detection
Authors: Bai Li Bing , Tian Shu Lin , Cheng Yu Hua
Published: March 2011

A novel visual detection set, which can detect sub-superficial defects in conductive specimens, is presented in this paper. The set has a laser source, a charge coupled device (CCD) camera, and a magnetic excitation. The linear polarized light given off by the laser source is modulated by the superimposition of the magnetic fields induced by the coil and eddy current, and acquired by the CCD. Given the exciting current is known and the eddy current is influenced by the defects, the information of defects can be extracted from the image acquired by CCD. The magnet excitation and image processing are described in detail. Experimental tests have been done and the method presented is proved by the experimental results.
The Simulation Analysis of Semi-Active Suspension System in Vehicle Based on Sliding Mode Control with Varying Structure
Authors: Zhang Jing Jun , Han Wei Sha , Cao Li Ya , Gao Rui Zhen
Published: March 2011

A sliding mode controller for semi-active suspension system of a quarter car is designed with sliding model varying structure control method. This controller chooses Skyhook as a reference model, and to force the tracking error dynamics between the reference model and the plant in an asymptotically stable sliding mode. An equal near rate is used to improve the dynamic quality of sliding mode motion. Simulation result shows that the stability of performance of the sliding-mode controller can effectively improve the driving smoothness and safety.
Recent Advances and Unsolved Problems of Grain Boundary Diffusion
Authors: Divinski Sergiy V. , Bokstein Boris S.
Published: March 2011

Some unresolved problems of grain boundary diffusion – restrictions of Fisher-Gibbs model, refinement of the conditions for B- and C-regimes, relation between segregation (s) and enrichment (b) coefficients, grain boundary width, non-linear segregation effects on grain boundary diffusion – are discussed.
Unprecedented Wealth of Information on Guest Dynamics in Nanoporous Materials from Transient Concentration Profiles
Authors: Chmelik Christian , Kärger Jörg
Published: March 2011

The application of interference microscopy (IFM) and infrared microscopy (IRM) to monitor the evolution of the concentration of guest molecules in nanoporous host materials opens a new field of diffusion research in condensed matter. It combines the methodical virtues of the profiling methods of solid-state diffusion studies with the benefit of the mobility enhancement in fluids. We are going to illustrate the rich options of diffusion studies provided by this novel experimental approach.
Diffusion Spreading of the Emitted Metallurgical Gas
Authors: Vishnyakova K.V. , Petelin A.L. , Yusphin Yu.S.
Published: March 2011

The main parameter which shows the space distribution of the emitted gas components is the rate of concentration decrease by the increase of the distance from the point where the emitted gas appears in the atmosphere. It is considered three different driving forces leading to the spreading of the emitted gas components from the centre of the metallurgical region to its periphery:  diffusion factor – the appearance of the emitted substance is the reason of the local concentration increase, it correlates with the diffusion process;  wind load factor – the wind movement acts always in advantage direction, wind force is not space homogeneous as the diffusion force is;  chemical factor – the intensity of chemical interaction of emitted components with the atmospheric ones influences the space distribution of the interaction products (secondary emissions). The proposed method allows to predict the space-time distribution of the emitted metallurgical gas by various external conditions.
Low-Temperature Synthesis of Perovskites PbTiO3 and PbZrO3
Authors: Myatiev Ata , Krechetov Ilya
Published: March 2011

A method of metalorganic compounds pyrolysis for low-temperature (about 500–600 oC) synthesis of perovskites PbTiO3 and PbZrO3 was tested to obtain films of this structures on sapphire substrates. The qualitative and quantitative X-ray diffraction analysis (XRD) of the films was carried out. The analysis showed that films obtained at 550 oC contain perovskites PbZrO3 and PbTi3O7.
Thermodynamically Consistent Formulation of the Sedimentation in Solids and Liquids
Authors: Wierzba Bartek , Danielewski Marek
Published: March 2011

We propose a theoretical framework to derive a consistent set of equations describing sedimentation, i.e. diffusion induced by the gravity (centrifugal) field, in a multi component system. This procedure starts from the combined 1) mass conservation law, 2) equation of motion, 3) volume continuity equation and 4) Nernst-Planck flux formulae. The method known as bi-velocity or Darken model is based on the postulate of a unique transport mechanism for volume and mass. The concentration profile in the equilibrium state is found by solving the nonlinear set of equations. Example applications of this theory applied to Bi-Sb system is evidence of sedimentation of substitutional atoms in condensed matter via diffusion mechanisms.
Grain Boundary Segregation and Amount of Bulk Carbides in Severely Deformed Fe–C Alloys
Authors: Straumal Boris , Rodin A.O. , Petelin A.L. , Baretzky Brigitte , Protasova Svetlana , Dobatkin S.V. , Dutta Majumdar J. , Manna I.
Published: March 2011

The microstructure, phase composition, Mössbauer spectra, grain boundary segregation and magnetic properties of binary Fe–C alloys with carbon concentration of 0.05, 0.10, 0.20, 0.25, 0.45, 0.60, 1.3, 1.5 and 1.7 wt. % were studied in the as-cast state, after a long annealing at 725°C and after high-pressure torsion (HPT) at the ambient temperature and 5 GPa with 5 anvil rotations (shear strain about 6). The grain size after HPT was in the nanometer range. Only Fe3C (cementite) and -Fe remain in the alloys after HPT. It was also shown that the less stable Hägg carbide (Fe5C2) and retained austenite disappear, and phase composition closely approaches the equilibrium corresponding to the HPT temperature and pressure. Measurements of saturation magnetization and Mössbauer effect reveal that the amount of cementite decreases after HPT. The reason for partial cementite dissolution is the formation of the carbon-rich segregation layers in the ferrite grain boundaries.
TiO2 Nanomaterials Studied by 44Ti(EC)44Sc Time Differential Perturbed Angular Correlations: Volume and Surface Properties
Authors: Butz T. , Ryu S.B. , Jankuhn S. , Das S.K. , Ghoshal S.
Published: March 2011

TiO2 nanoparticles (anatase) with diameters between 2 and 4 nm were synthesized by controlled hydrolysis of a solution of titanium(IV)isopropoxide to which 44Ti in 4M HCl was added. Inactive nanoparticles were analyzed by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM), the active ones were analyzed by measuring the nuclear quadrupole interaction (NQI) of the I = 1 state in 44Sc using time differential perturbed angular correlation (TDPAC). Rather broad distributions were obtained. We also synthesized nanowires with typical diameters of 2 nm and 100 nm length using shape controllers. They were analyzed by HRTEM and XRD. The material turned out to be TiO2(B). The 44Ti was added by impregnation and diffusion at 180°C for two hours. Two well-defined NQI signals were observed which we tentatively assigned to the volume fraction and the “surface” fraction, i.e. Ti probes with OH-termination. In addition, we studied AMT-100 (anatase, uncoated, 6 nm) from Tayca, Eusolex T-2000 (rutile, Al2O3-coated, 20×20×100 nm3, simethicone additive) and P25 (mainly anatase, uncoated, 20 nm diameter) using the impregnation and diffusion method. P25 and the isolated rutile fraction from P25 yield spectra which correspond to anatase and rutile volume signals plus their surface signals, respectively. TDPAC thus proved very useful in characterizing the nanomaterials, especially their disorder, by measuring the NQI. In addition, information on surface properties is obtained. The relatively narrow surface signals indicate a lower degree of disorder and are possibly also a result of partial motional averaging of Ti-signals with OH-bonds due to mobile H-atoms.
Flow Behaviour of Magnetorheological Fluids, Considering the Challenge of Sealing in Blank Hydroforming in the Flange Area with Rectangular Leakage Area Cross-Sections
Authors: Rösel Sebastian , Merklein Marion
Published: March 2011

The need of light weight constructions and parts with tailored or even more homogeneous mechanical properties especially for structural components leads to the use of alternative forming technologies. These forming processes like sheet metal hydroforming are established to gain more flexibility and to increase the forming limits. But to apply this forming technology successfully, it is necessary to overcome some obstacles. One typical challenge for hydroforming of blanks, which has prevented further application of this technology, is the sealing of the cavity in the flange area. Nowadays there are a lot of basic approaches to accomplish a sealing in this tool area. Commonly a sealing can be reached by increasing the contact pressure in the outer region of the blank. This approach reduces the possible blank draw in and hence abates the possible realisation of complex part geometries. One possible approach to increase the ratio between cavity pressure and contact pressure in the flange area is the choice of a capable active fluid medium. The aim is to reduce the contact pressure in the flange area and nevertheless ensure a complete sealing. In this case the magnetorheological fluid (MR-fluid) BASF Basonetic 5030 is used as a pressure medium for hydroforming. For characterizing this fluid under different amounts of magnetic flux density and in comparison to a common hydraulic medium, an experimental setup was built up to gain process relevant data for hydroforming processes. Therefore different experiments were carried out with different media and different flux densities for the MR-fluid. To get more information about the mode of action and the accessible amounts of cavity pressure and related contact pressures in the flange area, these two process parameters were varied.
Optimisation of Tubular Hydroforming Processes for Wrinkling and Thinning Control
Authors: Caseiro João F.M. , Valente Robertt , Andrade-Campos António , Natal Jorge Renato
Published: March 2011

This paper is focused on the development and implementation of an innovative optimisation algorithm for the wrinkling and thinning control during the hydroforming of complex metallic parts. A straightforward numerical algorithm for simultaneous tracking and evaluation of the initiation of wrinkling/thinning defects was implemented, together with a numerical simulation program based on the Finite Element Method (FEM). After undesirable wrinkling/thinning patterns are identified during FEM simulation, the developed optimisation procedure (called Hybrid Differential Evolution Particle Swarm Optimisation - HDEPSO) is responsible to automatically correct the process input parameters, in order to achieve the successful forming of the desired part. In the end, the combined procedure (optimisation methodology + FEM) proved to be able to lead to a suitable numerical simulation and design tool for industrial hydroformed metallic tubular parts.
Development of a Hydraulic Actuator to Superimpose Oscillation in Metal-Forming Presses
Authors: Behrens Bernd-Arno , Hübner Sven , Krimm Richard , Wager Christian , Vucetic Milan , Cahyono Teguh
Published: March 2011

A novel principle of a rotary piston valve and a high-frequency cylinder for a hydraulic actuation system are presented. This system will be utilized in metal-forming presses to superimpose a high-frequency oscillation on the movement of the ram. This technique was proven to enhance the forming parts quality, to extend the process limits and to reduce the forming force significantly. The key components of the valve are a stator and a rotary piston with radial drilled holes that is designed to provide a pulsating pressure and mass flow rate at a high frequency. A hydraulic cylinder is connected to the valve and converts the pulsating flow into a dynamic process force. The valve and the cylinder will be mounted on the bolster plate of a metal-forming press. In order to superimpose oscillation in the main forming direction, the cylinder is centered under the punch of the metal-forming tool. Three-dimensional computational fluid dynamics (CFD) simulations have been conducted to evaluate and to optimize the designs of the main components of the system. Hereby the commercial simulation code of ANSYS CFX was employed to determine the properties of the cylinder and the valve. Through its mesh motion technique, this simulation code allows the flow analysis between the rotary and the stationary part of the valve. Furthermore the dynamic characteristics of the system have been investigated under the influence of inertia and the compressibility of oil.