bluuebunny/crossref_metadata_2025 huggingface dataset:
A Super-Stable Optical Interferometer with Multi-Pass and its Simple Application
Authors: Xia Li Xin , Lei Qian Zhao
Published: August 2011

In this paper, we design a super-stable optical interferometer with multi-pass. By using single photon to estimate an unknown phase, our scheme enables considerable high precision and it can beat the standard quantum limit.
Key Technologies in Image Processing of Interferogram
Authors: Su Jun Hong , Wan Wen Bo , Yang Li Hong , Xu Jun Qi
Published: August 2011

Interferogram processing is one of main techniques in optical interferometry metrology. Modern interferometry for thin-film thickness has the advantages of noncontact and high accuracy, etc. Interferogram processing is important Step of interferometry. This article is the sum-up about the key technology of interferogram processing in interferometry, it reduce key technology of interferogram processing to three steps: removing the noise, edge detection, region spreading and phase unwrapping. Interferogram processing can be realized by using software developed by the key technologies. Then getting surface of the measured material object, thus the measured material object is measured automatically. In this paper, the thin-film thickness is determined by the key technologies, setting the results of this method against results from ZYGO, the PV error and RMS maximum error are 0.0364λ and 0.002λ respectively. Although single interferogram was processed in this study, a phase distribution with high accuracy was achieved.
Double Loop Autopilot Design Based on Frequency Domain
Authors: Pang Mei Sa , Li Deng Hua , Fan Jun Fang , Li Xue Fei
Published: August 2011

The static stability of missile pitching movement is one of the important performances in guidance and control systems. In this paper, a method which consists of the single and double loop longitudinal autopilot using frequency domain approach is proposed to solve the problem efficiently. Single-loop autopilot is used to simplify the system design when the missile is highly static stable; the double-loop autopilot is employed to stabilize the system and improve frequency performance when the missile is static stable or static unstable. Control gain of the system is determined by aerodynamic parameters and frequency domain indexes. The simulation result shows that double-loop autopilot based on frequency domain simplified the system design and improved the stability and robustness of missile system.
Research on Harmonic Detection Methods of Electrified Railway
Authors: Xu Xiang Zheng , Wan Wei
Published: August 2011

This paper introduces the characteristics of the traction power system of electric railway, and explores the harms to the power system caused by electric railway and the necessity of harmonic suppression of traction power supply system. In order to achieve real-time detection and compensation for harmonic waves of electric railway traction power system, this paper provides an improved harmonic detection method with initial compensating angle of delay time. Detection method is simple, and has better real-time, it can be used to detect selective harmonic for electrified railway.
The Radial Velocity Measurement and Error Analysis for Low Resolution Spectra
Authors: He Bin , Zuo Fang , Luo A Li , Li Yin Bi
Published: August 2011

Radial velocity error of the spectra always be given by the widths of the cross-correlation function of the target spectrum and template spectrum. Radial velocity error affected by many inevitable factors, caused by instrument, observation weather, etc.. Another important error comes from calibration, which should be reduced as much as possible. This paper analysis the error based on different temperatures for different types of spectral. The effect of the calibration error to the radial velocity error is also presented.
Secondary Optical Design of LED Road Lights
Authors: Gao Tie Cheng , Ai Yan Jin , Li Xiu Yan
Published: August 2011

Aiming to the application of high-power LEDs in road lights, this article discusses the requirements of optical properties of LED road lights. It carries out the reflector-based secondary optical design of the selected LEDs, which is simulated with ASAP. The results show that this design can take full advantage of the optical properties of LED light sources, greatly improve the efficiency of LED road lights, and improve the uniformity of road lighting, so as to achieve the effects with which those effects produced from the traditional lights cannot be compared.
Fabric Defect Detection Method Based on Gabor Filters
Authors: Liu Yan Bei , Xiao Zhi Tao , Zhang Fang , Wu Jun
Published: August 2011

In this paper, a fabric defect detection method based on Gabor filter bank is present. In this method, the parameters of Gabor filter bank depend on the fabric texture feature. Using the Gabor filter bank with multi-frequency and multi-orientation, a textile image produces multi-image. Then, the images are reconstructed into one image for detecting defects. It is illustrated that most kinds of defects are correctly detected and segmented. The experimental results show that the algorithm is robust and has good detection effect.
Improvement of Gaussian Random Measurement Matrices in Compressed Sensing
Authors: Wang Biao , Ma She Xiang
Published: August 2011

Compressed sensing seeks to recover a sparse or compressible signal from a small number of linear and non-adaptive measurements. Gaussian random matrix is a kind of fundamental measurement matrices, but its performance isn’t perfect because of more errors in recovery. This paper studies a new kind of matrix based on improving Gaussian random matrices. Measure sparse signals with improved matrices and recover original signals with orthogonal matching pursuit. Numerical experiments showed that the quality of recovered signal by improved measurement matrices is better than Gaussian random matrices.
Design of Antenna with a Solar Cell as a Parasitic Element in the UHF RFID Tag
Authors: Wan Xin Ning , Li Jian Xiong , Cui Xu Sheng , Mao Lu Hong
Published: August 2011

This paper presents a novel RFID antenna which makes solar cell and tag antenna combine as an integrated unit. The solar cell is used as a parasitic element in a tag antenna. The original feature of a solar cell (DC current generation) remains, and the solar cell which can supply the energy to activate the IC is now used as a parasitic patch at the same time. Besides a general description of solar cell antenna, the size and the simulated results of the antenna are also shown.
The Design of Large Image Scan Using Phototransistor Array
Authors: Zhang Zi Hong , Luo Rui , Li Jun Sheng
Published: August 2011

This project produces a system that Handles the entire scan routine on the MCU of STC12C5A60S2. This file contains the control of the stepper motors as they move the scanner head across the entire platform. Also starts the ADC conversions for scanning light intensity using the phototransistors and sends them to MATLAB. Nothing is done until a start command is received from MATLAB, in the form of the ASCII string "start". The stop command is conversely, the ASCII string "stop"
Experimental Study on Strength Characteristics of Cement-Soil under Fixed Spherical Pressure Condition
Authors: Song Xin Jiang , Wang Wei , Xu Hai Bo
Published: August 2011

Strength characteristics play an important role in mechanic behavior of cement-soil. Laboratory tests on cement-soil with 12% cement ratio and 28 d curing time are conducted by using a new multifunctional triaxial apparatus under fixed spherical pressure condition. Seven series spherical pressures are designed to apply, namely 300 kPa, 400 kPa, 500kPa, 600 kPa, 800 kPa, 1000 kPa, and 1200 kPa. At the same time, seven series consolidation pressures are taken into accounted. Tested data show that: (1) the stress-strain curve of cement-soil is characterized by strain softening, and the soften rate is related to confining pressure; (2) shrinkage or dilatancy of cement-soil volume strongly depend on the value of loaded spherical pressure; (3) failure curve of cement-soil is approximately a line and it agrees with the Mohr-Coulumb criterion. The result of this paper is helpful to the numerical analysis and practical engineering design of cement-soil foundation structures.
Effect of Voids on Moisture Absorption of CFRP Laminates in Hygrothermal Environment
Authors: Zhang A Ying , Zhang Jian She , Li Yu Cheng , Li Di Hong , Zhang Dong Xing , Xiao Hai Ying , Jia Jin
Published: August 2011

The effect of voids on moisture absorption of T300/914 laminates was discussed in this paper. The experimental results revealed that the moisture content increases with the immersion time at first and then reach a pseudo equilibrium state for the compressive and bending specimens. The saturated moisture content and the rate of water uptake increased with porosity increasing from 0.71% to 1.50%, which proved voids accelerate moisture absorption. The geometry of the specimens influences the moisture behavior. The saturated moisture content increased with the decreasing width of the specimens. The most significant increase in dimensional change is in the thickness and length direction, followed by the width direction.
Finite Element Numerical Simulation of Two-Dimensional Ground Water Solute Migration Question
Authors: Zhao Meng Ling
Published: August 2011

The finite element numerical model of 2-D solute transport in ground water with variable was established under the condition of variety of the velocity of the movement of water is not too fast,and was carried on by the finite element numerical simulation method.the numerical simulation shows that the calculated result is in good agreement with the experiment result.
The Energy Saving Effect Evaluation for Outside Wall with Different Material in Island District
Authors: Zhang Yan , Gong Xi Wu
Published: August 2011

In order to evaluate the energy saving effect for building outside wall under the damp island environment, the heat insulation performance of brick wall, MU10 concrete brick wall and aerated concrete are tested. The testing method is combined of infrared photos and heat flow meter. The results showed that the insulation performance of clay brick is worst, its heat transfer coefficient is 60% more than that required by energy saving standard. Although the concrete brick has painted 25mm polystyrene granule outside, the heat transfer coefficient is still smaller than energy saving standard required. The economic thickness of polystyrene granule is 79mm , which makes the both heating cost and insulating layer minimum during the life cycle of heat insulating layer. Among the three types of outside wall, only the aerated concrete can satisfy the energy saving standard for hot summer and cold winter district, it constitutes the self-insulating system.
Strain Performance of Fiber Bragg Grating Sensor Fixed by Different Adhesives
Authors: Gong Hua Ping , Li Xiao Rui , Jin Yong Xing , Dong Xin Yong
Published: August 2011

The influence of fixing adhesives on strain performance of fiber Bragg grating (FBG) sensor was investigated. A FBG sensor was fixed on the uniform strength beam with three kinds of adhesives, which are modified acrylate, glass glue and epoxy resin. The linearity, sensitivity and their stability of FBG sensor fixed by three kinds of adhesives were measured and analyzed at the temperatures 0ºC-40ºC. The results show that, the FBG sensor fixed by the modified acrylate has a high linearity, sensitivity and stability at different temperatures. The FBG sensor fixed by the glass glue also has a high linearity and stability, but it has a low sensitivity. When the FBG sensor is fixed by epoxy resin, the sensitivity and linearity is affected significantly by the temperature. In addition, the performance of the FBG sensor fixed by the modified acrylate has a good stability for a certain period of time.
AE Signal Analysis of Carbon Fiber Reinforced Composites Based on Hilbert-Huang Transform
Authors: Lu Chao , Ding Peng , Chen Zheng Hua
Published: August 2011

The AE signals of fiber reinforced composites in the tensile testing were processed by Hilbert-Huang transform. The AE signals were well recognized from the Hilbert-Huang spectrum. The experimental results show that the frequency range of matrix crack AE signals is below 200 kHz and the main frequency is nearly in 175 kHz. The frequency range of fiber breakage is above 200 kHz and the main frequency is nearly 250 kHz. While the frequency of delaminations is distributed all over the frequency range and the energy is distributed below 200 kHz. The experimental results also indicted that the intrinsic mode function (IMF) components of the AE signals processed by empirical mode decomposition (EMD) can reconstruct the original signals well, and the Hilbert spectrum of the IMF components can reveal the frequency and energy trends of AE signals.
Microscopic Displacement Mechanism of Surfactant/Polymer Driving Residual Oil in Conglomerate Reservoir
Authors: Cong Su Nan , Liu Wei Dong
Published: August 2011

According to microcosmic porous and throats model’s experiment which will be performed in Kexia layer, Qizhong district of conglomerate reservoir in Xinjiang oil fields, microscopic displacement mechanism of surfactant/polymer flooding was researched. Surfactant/polymer flooding has a significant effect on enhancing oil recovery because of the effect from the polymer’s viscosity and the surfactant’s interfacial tension. According to microcosmic porous and throats model’s experiment, the best polymer viscosity and surfactant interfacial tension were determined.
The Three-Dimensional DEM Modeling of Gravel Materials
Authors: Luo Rui , Chen Ping , Yang Ting , Zhang Hui Zong , Li Ping , Zeng Ya Wu
Published: August 2011

The tomography of the gravel was obtained by the CT scanning technology to reconstruct the DEM models. Simultaneously, dimensional coordinates on the gravel’s surface were obtained. Then the surface of gravel was contracted and the coordinates of the shrunken shell were collected by the matlab [1] program. Based on these coordinates, two parameters which are radius threshold and overlapping factor were introduced to simulate the model. Then programs to reconstruct the DEM model were compiled. Spheres were used to rebuild the model and generate the irregular particle model automatically. The results indicated that the model was unique and the modeling process could be repeated. Simultaneously, the relationship between two parameters and the accuracy of the modeling were studied.
A Single-Polarization Single-Mode Photonic Crystal Fiber with Four Lines of Small Elliptical Air-Holes
Authors: Zheng Hong Jun , Wu Chong Qing , Wang Zhi , Wang Jian , Liu Shan Liang , Li Xin
Published: August 2011

We present a novel single-polarization single-mode photonic crystal fiber (SPSM-PCF) design with four lines of small elliptical air-holes in order to obtain wider bandwidth for SPSM operation. The characteristics of the proposed SPSM-PCF are studied by using a full-vector finite element method (FEM) with perfect matched layer (PML) boundary conditions. At the wavelength of 1.55 µm, the confinement loss of the x-polarized mode is lower than 0.5 dB/km, whereas the loss of the y-polarized mode is larger than 50 dB/km. Compared with the case of x-polarized mode, the y-polarized mode can be suppressed in the PCF. Then, the SPSM operation is obtained. The proposed PCF can perform SPSM operation with broadband of 600 nm for considering the confinement loss ratio and the loss difference.
Principle and Method for Oxidation Layer Measurement in Electrolytic In-Process Dressing (ELID) Grinding
Authors: Ma Bao Ji , Wang Yin Xia
Published: August 2011

Based on the analysis of formation and variation characteristics of oxide layers in ELID grinding, a new measurement principle and method for oxide layer measurement in ELID grinding was proposed. The thickness of the oxide layer was obtained based on measurement both outside surface and inner surface of the oxide layer by laser sensor and eddy current sensor. Calculation methods for measurement of the oxide layer in different ELID grinding periods were presented. In order to verify the correctness of the measurement principle and measurement method, evaluation experiments were down. Results show that the precision of the measurement is sufficient to be applied in ELID grinding.
Camping Performance Experiment of Gas Thrust Bearing with Elastic Pressure Equalizing Groove
Authors: Zhang Jun An , Ren Kai , Wang Lina , Liu Bo
Published: August 2011

Camping is a major parameter of floatation cushion dynamic performance, we could get floatation cushion dynamic performance parameter through research floatation cushion camping performance.This paper uses experiment method to measure floatation cushion film gap and then data processing is by wavelet felixgong principle.Through the comparison of two curves we can observe that the camping of the gas lubricated thrust bearing with elastic pressure equalizing groove is obviously bigger than the gas lubricated thrust bearing with stiffness pressure equalizing groove.So elastic cushion could decay the external drive faster which can improve the cushion’s stability and could be widely used in the future.
Study on Al-Doped ZnO Nanofibers Prepared by Electro-Spinning Technique
Authors: Li Qin , Zhang Hai Ming
Published: August 2011

PVA/ zinc acetate sol–gel were fabricated into thin PVA/ zinc acetate composited fibers films by using electrospinning technique. After annealing of the above precursor fibers, ZnO:Al nanofibers with a diameter of 100-700 nm and high length-diameter ratio were obtained successfully. The ZnO:Al nanofibers were characterized by XRD, SEM, and PL, respectively. The XRD results show that Al-doped ZnO nanofibers present ZnO hexagonal structure. PL spectra display that the ZnO: Al nano-fibers have a strong UV emission properties.
Study on Bonding Wire Breakage Detection Using Diffraction of Light
Authors: Wang Xiao Yan , Xiao Yong , Ge Xiao Yu , Sun Jing Na
Published: August 2011

In manufacturing industry, bonding wires are used to interconnect the pads of a semiconductor chip to terminals of a package containing the chip. With increasing demand of tiny wires, current detection apparatus encounters some limitations. In this paper, a method to detect breakage of tiny bonding wires using diffraction of light is proposed. A laser head generates the light beam, and a slit is introduced in the path of light source, so the slot generates diffraction pattern, and light irradiance loss at the receiver due to the presence of a wire could be observed. Simulation results show that the proposed method with a slit design renders satisfactory detection sensitivity for tiny wires.
Determination of Cadmium in Bivalve Molluscs by Microwave Digestion with Inductively Coupled Plasma-Mass Spectrometry
Authors: Jin Gao Wa , Gong Qian , Cai You Qiong , Li Xiao Lei , Shi Yong Fu , Gu Run Run , Yang Qiao
Published: August 2011

A method based on microwave digestion and inductively coupled plasma-mass spectrometry (ICP-MS) has been established for the sensitive determination of cadmium in bivalve molluscs. The application of the internal standards calibration improved the accuracy and precision values of the method. The relative standard deviation (RSD), the standard addition recovery value and the detection limit were determined as 4.25%, 94.74% and 0.005 μg/L, respectively. This method has been verified by the determination of cadmium in certified reference material kelp (GBW08517) and mussel (GBW08571). The method has been applied to determine the contamination concentration level of cadmium in seven kinds of bivalve mollusk samples. The results indicated that, among them, mud clam, scallop and oyster have relative high accumulation ability to cadmium.
Mechanism Analysis of Induction-Type Coil Target for Velocity Measurement
Authors: Xiong Xian Feng , Kong De Ren , Ruan Xiao Feng
Published: August 2011

Induction-type coil target is a common used zone-block device for measuring projectile’s velocity. The magnetized projectile is simplified as the point magnetic dipole, and then the physical model of magnetized projectile passing through the coil target is established, based on these the mathematic model of inductive electromotive force when the magnetized projectile flying through the coil target in a certain speed is deduced with the electromagnetic theory; According to the model, the characteristic parameters such as the zero-crossing point, the slope of zero-crossing point and the extreme value point are discussed, finally the principle and the influence factors of velocity measurement by single-coil target and paired- coil targets are described. All these above provide some foundation and advices for designing and using induction-type coil target.
A Novel Elman Algorithm Based on Sectional Least Squares
Authors: Tan Wen Xue , Pan Mei Sen , Xu Xiao Rong
Published: August 2011

In this paper, a novel algorithm named SLS-Elman is put forward, which aims at more effectively training and learning small scale samples with many characteristic variables, and takes Sectional Least Squares principle and some structural property of Elman neural network into consideration. When doing characteristic variable reduction on high-dimension of small scale samples, the novelty algorithm takes relativity among dependent variables into account. Obtained data by this algorithm carry on training and simulating on a neural network; outputted network is more simplified in view of structure, and presents a more precise network model. The statistics of case analysis demonstrates novelty algorithm improves convergence rate and forecast precision, and efficiency. In the mean time, on purpose to test efficiency of novelty algorithm, it is compared with some algorithms such as Elman neural network algorithm based on Principal Component Analysis and so on, as a result, it presents more advantages.
Loading Priority Evaluation Based on PRISM Classifier
Authors: Feng Yuan , Xia Li , Wang Li Ming , Bu Le Ping , Shao Ying
Published: August 2011

Loading management is one of the most important technologies for ship power system. Reasonable distribution of electric energy to the loading can achieve the goal of optimal energy schedule and its primary issue is to make a reasonable loading priority evaluation. This paper analyzed the shortcomings of the loading priority evaluation using the AHP and proposed a kind of algorithm of property weight evaluation based on PRISM classification, effectively combing expertise and characteristics of the objective data itself together. The results show that: the loading priority of ship power system is mainly affected by two properties of demand urgency and vulnerability. The results of various algorithms are basically consistent with the above conclusion, which proved the correctness of the algorithm. Comparison among various evaluation results tables shows that for the same weight measurement standard using different classification algorithm or property reduction algorithms, the results of its loading priority evaluation slightly differ.
Experimental Study of Static Aerodynamic Coefficients of Bridge Section
Authors: Gao Liang , Liu Jian Xin , Liu Miao
Published: August 2011

With HK-Zhuhai-Macau Bridge as the engineering background, through the section model wind tunnel test, research into the influence of vibration damping measure to the static aerodynamic coefficients of the structure, so as to seek to improve structural characteristics. The influencing factors of static aerodynamic coefficients including the guide plate position, the central trough opening rate, baluster drafty rate, repair car track position, windbreak, and vehicle. The results show that the changes of the static aerodynamic coefficients directly affect the static wind loads, and the influence of changes of these parameters to the static wind load cannot be ignored.
A Survey of Image Edge Detection Based on Grey Theory
Authors: Tian Hong Peng
Published: August 2011

Due to the feasibility and the efficiency in image engineering, Grey Theory proposed by Julong DENG has been paid more attention by many researchers at home and abroad. The feature of the theory lays in the fact that modeling or analysis is easy to implement even in the condition that only few samples are available. Many research fruits on digital image are produced so far. Focusing on edge detection of digital image, this paper gives a survey of the application and predicts some future developments after some basic theory are described.
Image Matching Based on Bacterial Foraging Algorithm
Authors: Tian Hong Peng
Published: August 2011

To increase the speed of image matching, this paper combines Bacterial Foraging Algorithm (BFA) of swarm intelligence with wavelet transform, and presents a fast matching method. The method regards the problem of image matching as a search for the optimal solution. To provide artificial bacterial swarm algorithm with an appropriate fitness function, the Normalized Product correlation (NPROD) is employed to measure the similarity between the template image and the searching image. Then the best coarse matching position is gradually approaching by chemotaxis, elimination and dispersal, and reproduction behaviors of artificial bacterial. Finally, the best matching position is found out according to the coarse matching position. Experimental results show that the proposed method is fast and efficient.
Simulation of Temperature and Stress Field of Titanium Alloys under Laser Cladding
Authors: Ren Zhi , Tian Yan Ling , Zhou Ming Yue , Zheng Huan Ying , Zhang Shuai
Published: August 2011

Titanium alloys which exhibit excellent material properties like a high strength to weight ratio and good corrosion resistance have become the important structural materials in the applications of the aerospace. However, it’s quite difficult to repair the damages of the titanium alloy parts such as fatigue crack and erosion resulted from poor working environment using the traditional manufacturing technology while the problem can be easily solved with the help of laser cladding technology. For the excellent quality of the fixed parts, it is extraordinarily significant to obtain the rule of the temperature and thermal stress distribution in the cladding process. To investigate the influencing rule of cladding coating's temperature and stress on laser cladding process parameters, the model of laser cladding based on TC4 titanium alloy is built by the way of finite element method (FEM). This model encompasses the effects of the temperature-dependent thermal conduction and radiation as well as the latent heat of fusion. Different laser processing parameters are chosen to calculate the temperature and stress of cladding layer.The result shows that the temperature of the clad coating is positive correlation with the raise of laser power and the depth of the powder layer, and negative correlation with the raise of scanning speed and the laser spot diameter. In addition, the transient stress of clad coating is augmented with the increase of laser scanning velocity, laser spot diameter and the depth of the clad coating while it’s negative correlation with the raise of laser power. The numerical results provide the theoretical guidance for optimization of the laser cladding parameters on TC4 titanium alloy.
Measurement and Analysis of the Chinese Elite Male Swimmers’ Basal Metabolism of Nicotinamide Using NMR-Based Metabonomic Technique
Authors: Li Jiang Hua
Published: August 2011

To explore the relationship between basal metabolism of the nicotinamide and the athletic ability of the elite swimmers, Sixteen Chinese male athletes participated in the short distance swimming competitions in the 15th Asian Games were recruited. Their morning urine samples were collected three times in a row, once a week in the month before the games, and the metabolite of nicotinamide, N-methylnicotinamide, was measured using nuclear magnetic resonance (NMR). Then the subjects were classified as finalists group and non-finalists group according to their performance in the games, and mean comparisons of the measured results was carried out between the groups with SPSS15.0. The relative concentrations of MNA in the urine from finalists group were significantly higher than from non-finalists group in every comparison (0.0000524 ± 0.0000281 VS. 0.0000195 ± 0.0000131, P<0.05; 0.0000221 ± 0.0000181 VS. 0.0000162 ± 0.0000151, P<0.05; 0.0003831 ± 0.0000373 VS. 0.0000636 ± 0.0000118, P<0.05). Higher level swimmers have relatively higher metabolic rates, which may help to form a more effective energy supplying mechanism and a higher tolerance to intense training and severe competitions.
Research on the Detection of Faulty Insulator Strings
Authors: Nie Yi Xiong , Peng Xian Gang , Xu Xiao Ning
Published: August 2011

A series of experiments on the corona current pulse appearing on insulators under various contamination conditions with AC voltage of different amplitude are described. The corona current pulses were found to follow the Gaussian distribution and can be used to distinguish the faulty insulators from normal insulator strings in transmission line. The probability formulas about the corona current pulses have been studied in detail. They can be used as a kind of criterions to detect the faulty insulators. With several established fuzzy membership functions of humidity and contamination through data from experiments, it is proved that the insulation state could be estimated from the transmission line insulator strings by the fuzzy logical reasoning. This method has been verified in the laboratory by simulating work conditions of insulator strings on an 110kV transmission line and has the advantage of safety and convenience.
Synthesis and Imidization of Polyamic Acid
Authors: Cheng Jian Li , Zhou Cun , Zheng Guo , Sun Yu
Published: August 2011

Polyamic acids (PAA) were synthesized by solution polycondensation of aromatic diamine with dianhydride and PAA were readily soluble in polar organic solvents (N-methylpyrrolidinone, N, N-dimethylacetamide and DMF). It was found that the most appropriated reaction conditions of synthesis of PAA solution were the ratio of dianhydride with diamine being 1.02:1and 3h reaction time at ambient temperature in both N-methylpyrrolidinone and N, N-dimethylacetamide polar organic solvents. PAA thin films were prepared by PAA solution spread on the glass plate and PI thin films were obtained by the casted thin films which underwent a special high-temperature (300°C, 2h) heat curing. The structures of PAA and PI films were characterized by FT-IR spectra and degree of imidization of PAA solution was indicated from IR spectra. The thermal stability was studied by thermogravimetric analysis (TGA) and the thermal behaviors were investigated by differential scanning calorimetry (DSC) in this paper. It was shown that PAA solution were imidization at 200°C mostly and PI had higher thermal stability.
Implementation for High-Precision and Non-Contact System for the Measurement of Crankshaft and Camshaft
Authors: Cheng Da Lin , Wang Yi , Ren Yong Jie , Yang Xue You
Published: August 2011

A novel crankshaft and camshaft measurement system by optoelectronic scanning of which a flat-crystal was used to generate high depth of parallelism scanning laser was implemented. The general structure and principle were given. Mass of test results showed that the system could achieve high precision. The ranges could achieve ±8μm, standard deviation could achieve 3μm, and easy to operate, work reliably, automatically and on line measurement could be implemented.
Preparation and Characteristics of Nanocrystalline Diamond Film by Using of MPVCD
Authors: Yang Bao Hua , Ma Hua Li , Lu Hong Yan , Zhang Xiao Bo
Published: August 2011

With the microwave plasma chemical vapor deposition (MPCVD), the effects of the deposition pressure and the different substrate temperature on diamond coating on single crystal silicon substrate were studied systemically. The sample was characterized by means of scanning electron microscopy (SEM) and laser Raman spectra (Raman). The experimental results showed that the surface of the film was compact, the mean particle diameter was 98nm, and that it contains thesp3carbon phase with good quality.
Prediction of Resilient Modulus for Hot Mix Asphalt Based on Artificial Neural Network
Authors: Hu Chun Hua
Published: August 2011

Resilient modulus of material is an important parameter for pavement structure design and analysis. However it is very tedious to get this parameter for hot mixture asphalt in laboratory. Moreover it takes long time to do experiments. In this paper, artificial neural network (ANN) is applied to predict to resilient modulus for hot mixture asphalt. A neural network model is constructed and trained plenty of times with selected test data until precision meets requirement. Then the model is used to predict resilient modulus for hot mix asphalt. Result of contrast prediction with test data shows that forecast precision is high. This provides a new method to predict resilient modulus for hot mixture asphalt.
An Instrument for Detecting Non Visible Corrosion of Prestressing Strands Using Guided Waves
Authors: Xu Jiang , Wu Xin Jun
Published: August 2011

Corrosion of prestressing strands is a main durability issue for prestressing structures. In general, the corrosion zones of strands are hidden in structures which lead to be hardly inspected by traditional methods. An instrument for detecting the non visible corrosion of prestressing strands using magnetostrictive guided waves is provided. The instrument is described in detail. The workflow to detect the strands is provided. Field trials and laboratory experiments show that the information of position, length and amount of the corrosion can be obtained from the data. The instrument provides support for ensuring the safety of prestressing structures.
Research and Application on the Crumb Rubber Modified Low-Noise Asphalt Pavement
Authors: Zhang Zhi Xiang , Liu Wei , Li Xiao Yan
Published: August 2011

In this paper, the research of Low-Noise Asphalt Pavement（LNAP）mix design with the crumb rubber has been studied, including materials selection, gradation selection, asphalt content selection, performance tests, and so on. To verify the high-temperature performance and the effect of noise reducing, the new test methods are studied in the lab. The On-board Sound Intensity (OBSI) is developed to measure the tire-pavement noise and evaluate the noise reducing effect of trial pavement. The QC and QA of LNAP is researched by the trial pavement and the tire-pavement noise is measured by the OBSI，the LNAP has not only the good performance but also low noise than the conventional asphalt pavement.
Preparation of Iron Nanoparticles and Steel Plant Wastewater Treatment
Authors: Zhu Yan , Yuan Shuai , Xu Zhi Yong , Liu Peng
Published: August 2011

The iron nanoparticles were prepared via a redox reaction between Fe2+ and BH4- in the SDS-ethanol-water system.The iron nanoparticles surface was treated by nickel salt solution. The particles were characterized by the Transmission Electronic Microscope(TEM) and X-Ray Diffraction(XRD).It is shown that γ type iron nanoparticles with a mean size of 50nm have been prepared. The wastewater in the steel plant was treated by the iron nanoparticles. It is shown that suspended substance and concentration of heavy metal ion in wastewater were brought down largely.
Rapid Determination of As, Sb, Bi and Hg in Gold Ore Samples by AFS with L-Cysteine as a Prereducer
Authors: Xiong Chuan Xin , Liu Ya Rong , Gu Juan Ping
Published: August 2011

The paper researched the method of using the L-Cysteine to pre-reduction and using hydrid atomic fluorescence spectrometry to determining the As、 Sb 、Bi and Hg elements.In the preparation determination condition,the elements have a wide linear rangeand, the sample analysis results coincided with the recommended values. Detection limit of each element wereAs0.08ng／mL、Sb 0.06ng／mL、Bi 0.07ng／mL、Hg 0.004ng／mL。After nearly more than 100,000 pieces of the determination of geochemical samples, the sample have a good parallel.
Proxy Re-Signature Scheme from CBS to IBS
Authors: Yang Hai Bin , Sun Juan Li , Wang Xu An , Cui Jian
Published: August 2011

In 1998, Blaze, Bleumer and Strauss proposed a new kind of cryptographic primitive called proxy re-signature. In proxy re-signature, a proxy can transform a signature computed under Alice’s secret key into one that can be verified by Bob’s public key. In 2005, Ateniese et al proposed a few re-signature schemes and also discussed its several potential applications. In this paper, we propose the first proxy re-signature scheme from certificate based signature (CBS) to identity based signature (IBS) with the help of PKG.
Multi-Feature Extraction for Drivable Road Region Detection with a Two-Dimensional Laser Range Finder
Authors: Hu Yu Wen , Li Xin , Gong Jian Wei
Published: August 2011

A multi-feature extraction method using a single 2D Laser Range Finder is proposed to provide the information of drivable road region for the Unmanned Ground Vehicle in structured environment. The whole process consists of two main steps: first, the curbs are extracted from the range data using the wavelet transform method, and evaluated by a road scanning model; then, the drivable region is detected based on the average height and flatness. A mathematical model for curb and road detection based on grid map is built to guide the vehicle. The algorithm distinguishes itself from the most existing methods which detect curbs only, it takes advantage of the flatness of surface between extracted curbs is employed as another feature for drivable road region detection. Furthermore, laser intensity data from the same laser range finder is introduced to supply a new restriction for surface evaluation. Experimental results verify the feasibility and stability of the method.
Experimental Research on Beneficiation Process for a Specularite Ore
Authors: Wang Wei Zhi , Zhang Jin Rui , Yang Chun Guang
Published: August 2011

An iron ore contains specularite and hematite which are its main iron minerals. And its main gangue minerals are specularite, part of the clay material and a small amount of quartz.Tests are made on the ore by adopting processes including gravity separation, high intensity magnetic separation, high intensity magnetic-gravity separation and high intensity magnetic - reverse flotation. The test results show that the separation process of high intensity magnetic-reverse flotation can obtain an iron concentrate grading about 66.62% at a recovery of 58.38％ from an iron ore assaying around 35.00% iron, rather good metallurgical performances.
Safety Following Space Modeling and Speed Control on Highway
Authors: Xie Lai Fa , Chen Kuan Min , Zhao Yang Dong
Published: August 2011

Due to the rapid development of economics and society, China has witnessed increasing highway accidents, especially rear end collisions that mainly caused by over-speeding or too close following distance. Based on the vehicle dynamic analysis, therefore, a 3 step-based safety following space identification model according to Mazda vehicle is proposed to describe the brake performance and three driving states are taken into considering, including total following state, part following state, and three-kind extreme states. Then, a self-adaptive fuzzy reasoning model is used to control the traveling speed so as to adjust the traffic flow as smoothly as possible. The Matlab simulation results shows this proposed fuzzy control model helps minimize the occurrence probability of rear-end collision on highway and improve the overall traffic safety performance and management level.
Designing of Armature Components' Composite Stiffness Measuring Device Structure
Authors: Wang Hui Feng , Wang Guang Lin , Zeng Qi Wen , Lu Ze Sheng
Published: August 2011

A device used in measuring composite stiffness of armature components (CSAC) is developed according to the proposed definition of CSAC. Couple exerting and measuring mechanism, rotary actuator structure and fixture of armature components are introduced in this paper.
Study on Control of Brushless DC Motor for Electric Vehicle
Authors: Cao Jian Bo , Mao Ming Qiang , Xu Wan Lu , Ji Jia , Jiang Jia , Yu Jie
Published: August 2011

To deal with the control problem of brushless DC motor (BLDCM), based on analyzing the work principle of BLDCM, the fuzzy-PID control was studied, and the fuzzy-PID controller of BLDCM was designed. The experimental results show that the fuzzy-PID controller is superior to the PID controller at steady-state tracking error. Additionally, the current and torque undulation of BLDCM were also improved.
The Characteristics of the Fatigue Failure in the Disposable Machinery
Authors: Li Yue Feng , Pan Xu Dong , Wang Guang Lin , Lin Zhuo , Kang Xiao
Published: August 2011

The disposable mechanism is a kind of extraordinary mechanism widely applied in plenty of fields such as aerospace and military industries. Different from the conventional mechanism, it is known for its short work time. Thus, the conception of designing such mechanism is based on static strength check, neglecting other factors including fatigue and abrasions which gradually lead to invalidity. This paper mainly discusses the feasibility of neglecting fatigue in disposable mechanical design and lays the foundation of the principles in such design theoretically.
Experiment Study of Adiabatic Shear Critical Conditions in Orthogonal Cutting of Fe-36Ni Invar Alloy
Authors: Li Guo He , Qi Hou Jun , Yan Bing
Published: August 2011

Orthogonal cutting experiments of Fe-36Ni invar alloy are performed. The change of chip morphology with cutting conditions are investigated through metallurgical observation, and the critical cutting speed of adiabatic shear for Fe-36Ni invar alloy at different cutting depths and rake angles are given. In addition, the characteristic of chip deformation before the occurrence of adiabatic shear is also analyzed. The results show that the critical cutting speed decreases with the increase of cutting depth and hardness, but increases with the increase of rake angle. The deformation coefficient tends to a constant value with the increase of cutting speed.
A New Control Algorithm for Maximum Power Point Tracking of Photovoltaic Generation System
Authors: He Xin Sheng , Gao Chun Fu , Wang Bin , Luo Zhi Yong
Published: August 2011

In order to maximize the power of photovoltaic generation system, it is necessary to track the maximum power point (MPP). A new control algorithm of photovoltaic (PV) was proprosed, which applied constant voltage tracking method (CVT) to adjust the working point around the MPP and ensure fast tracking when external conditions or loads changed suddenly. The algorithm used the optimal gradient method (OG) to make optimization of the steady-state characteristic and could effectively reduce the output power of photovoltaic array oscillation around maximum power point tracking (MPPT). The experiment and simulation results show that the proposed algorithm could track the MPP rapidly and accurately. And also could improve the energy conversion efficiency of PV generation system by reducing the output power oscillation around MPP.
Simulation Analysis of Fluid-Structure Interactions with Moving Mesh
Authors: Sun Ming Li , Wu De , Wang Ming Qiang , Jin Sheng Fei , Wang Kan Zhi
Published: August 2011

This paper demonstrates techniques for modeling fluid-structure interactions with moving mesh in COMSOL Multiphysics. It illustrates how fluid flow can deform surrounding structures and how to solve for the flow in a continuously deforming geometry using the arbitrary Lagrangian-Eulerian (ALE) technique. The ALE method handles the dynamics of the deforming geometry and the moving boundaries with a moving grid.
Based on LS-DYNA Dynamic Simulation Analysis in Electroplated CBN Hard Gear-Honing Processing
Authors: Zhang Man Dong , Lv Ming
Published: August 2011

In general, using electroplating CBN hard gear-honing-tools with standard involute, the vicinity of the workpiece tooth pitch circle will be a “mid concave” error, the root of the tooth will be a “dig root” error. For the form factors of the error are more complicated, it is difficult to calculate errors with an exact analytical method. To this end, by the help of Pro/E and ANSYS/LS-DYNA software, the analysis of electroplating CBN hard honing process was dynamically simulated. Through picking up the datum from analysis results, the von mises stress distribution curve was drafted along engaging points on the tooth surface, this revealed the internal factors of the tooth profile error formation, also determined the location and extent of the tooth profile errors. It is provided a theoretical basis to make the gear-honing-tool tooth surface modification as possible, and the result is consistent with the actual processing.
The Research Trends and Comprehensive Evaluation of Hybrid Excavator
Authors: Wang Dong Yun , Zhang Yu
Published: August 2011

The energy saving of hydraulic excavator meets it’s bottle-neck. The load characteristic and working condition are analyzed. And the applicable of hybrid power technology which is widely researched on vehicle is introduced. It suggests great effects on energy saving and may break up the bottle-neck. In order to compare the fuel consumption of the three kinds of excavator: normal, series and parallel, the matlab/simulink model of series and parallel hybrid excavator are founded and the load chart is collected from a 5t excavator. Based on simulation results, the two kinds of hybrid excavator are compared from the three aspects: manufacture cost, operation performance and component performance. The results indicate that the parallel configuration with directory electrical motor rotary driving and regeneration rotary braking is the currently main developing program.
A Minimum Cost and Maximum Flow Model of Hazardous Materials Transportation
Authors: Gao Qing Ping
Published: August 2011

A vehicle routing problem of hazardous materials transportation is studied in this paper. Firstly, the maximum permissible flow of the road section is calculated according to the social risk and accident rate values. Secondly, based on the structural measures and basic transportation network, the maximum permissible flow of the road section is taken as road section capacity, the minimum risk is taken as general minimum cost , and a minimum cost and maximum flow method is introduced to solve the flow distribution problem of hazardous materials transportation. Finally, the effectiveness of the method is illustrated with a simple numerical example.
Control Research on Construction Excitation Frequency of Resonant Rubblization Machine
Authors: Qiu Xin , Yang Qing , Chen Lan Yun
Published: August 2011

Based on the assumption of thin plate of elastic foundation and vibration theory, a method for calculating the fundamental natural frequency of cement slab is presented and the influence of slab dimension and foundation reaction modulus on the fundamental natural frequency of cement slab is discussed. As well, according to the analysis results of fundamental natural frequencies of typical cement pavements of China, the selected proposals of the excitation frequency of the resonant rubblization machine are presented. The research results provide a theory support to popularize resonant rubblization technology in overlaying and rebuilding engineering of the existed cement pavements in China.
Study on Processing Technology of Waste Tire Crumb Rubber Modified Asphalt
Authors: Chen Lan Yun , Cong Zhuo Hong , You Qing Long , Zheng Nan Xiang
Published: August 2011

The rapid development of automotive brought a lot of accumulation of waste tires. Waste tire crumb rubber mixed with asphalt not only eliminates its impact to the environment, but also improves the performance of asphalt. Crumb rubber modified asphalt was made by the high-speed shearing device using waste tire crumb rubber mixed with Karamay-90 asphalt. The influence of mixed time, stirring time, processing temperature and the fineness of crumb rubber to the performance of crumb rubber modified asphalt was studied.The best processing technology of crumb rubber modified asphalt was obtained.