bluuebunny/crossref_metadata_2025 huggingface dataset:
Systematic Study of Resonant Pattern in Ellipsoidal Microwave Cavities
Authors: Li Xiao Jing , Zheng Shun Qi , Zhao Bao Rong , Zhang Xi Wen , Tang Wei Zhong
Published: December 2012

Resonant pattern in ellipsoidal microwave cavities were analyzed systematically in this article. Electric field distribution in cavities with different sizes was calculated by the finite difference time-domain method (FDTD). The results of the simulation show that, the microwave fed in though antenna, two different transmission patterns be formed in the microwave cavities, when the R and Z were properly chosen．In the first case, only one strong electric field area was formed at the bottom of the ellipsoidal cavity. For the second case, two main strong electric-field areas around the focal points, resonant series “TM0mn” mode were also found, the size of ellipsoid resonant cavities reveals obvious regularity in the resonant series, the electric-field shape of a resonant mode is similar with each other except that the intensity of the two main strong electric-field areas. In the same resonant mode, z has a good linear correlation with r. the research results of the ellipsoidal microwave cavities with two main strong electric-field areas will provide more choices for design new plasma reactors.
Response Spectrum 0.9-2.65 μm of In0.82Ga0.18As Detectors by Two-Step Growth Technique
Authors: Zhang Tie Min , Miao Guo Qing , Fu Jun , Ban Dong Mei , Shen Zhen Jiang , Lin Hong , Zou Xu , Peng Hong Yan
Published: December 2012

InP/In0.82Ga0.18As/InP heterostructure used for infrared detector were grown on (100) S-doped InP substrates using two-step growth technique by low temperature metal-organic chemical vapor deposition. The growth was performed using TMIn, TMGa, AsH3, and PH3 as growth precursors in a horizontal reactor. The substrates on a graphite susceptor were heated by inductively coupling RF power, their temperatures were detected by a thermocouple, and the reactor pressure was kept at 10000 Pa. The growth structure of detector included In0.82Ga0.18As buffer with the thickness of 100 nm, In0.82Ga0.18As absorption layer with the thickness of 2.8 μm, and the InP cap with the thickness of 0.8 μm. The planar type of p-i-n detector was fabricated by Zn diffusion. The properties of In0.82Ga0.18As detector were studied, the curves of the I-V characteristics, the range of response spectrum, and the detectivity (D*) were obtained.
Tube Extrusion Technology for Super-Alloy Inconel690
Authors: Wang Zhong Tang , Zhang Shi Hong , Deng Yong Gang
Published: December 2012

Finite element software was used to analyze the deformation of hot extrusion technology at high temperature and high speed for super-alloy Inconel 690(IN690). It had been obtained that the temperature filed and strain filed and stress field during tube extrusion deformation at different speeds and temperatures. The results presented that deformation uniformity being fine and the temperature variety increased with increasing of extruding speed. The maximal equivalent stress decreased and the distributing was further uniformity with the increasing of deformation temperature. Extrusion force reduced at first and then increased with increasing of extruding speed. Maximal extrusion force reduced with the increasing of deformation temperature. The relative errors of extrusion force between simulating results and experiment results are less than 7.3%. Extrusion technology parameters for supper-alloy Inconel690 had been optimized which are that extrusion speed being 110 ~ 120mm / s, and extrusion temperature being 1200 °C.
Preparation and Transport Properties of Superconducting Fete Thin Film
Authors: Yang Chuan Sen , Cao Li Xin , Chen Ning , Li Wei Yong , Liu Li Hua , Zhang Ying Zi
Published: December 2012

We successfully deposited the purely c-axis oriented Fete thin film, which shows superconducting transition in electrical resistivity about 12 K, by using pulsed laser deposition method. The electrical transport measurements of the thin film are studied with magnetic fields up to 14.0 T. thermally activated energy is analyzed using simple conventional Arrhenius relation and more precise relation who is closer to experimental results. Besides, the upper critical magnetic field and the vortex glass transition temperatures for the Fete thin film are studied.
Effects of Copper Interlayer and Annealing on Structure and Mechanical Properties of Diamond-Like Carbon Films by Cathode Arc Evaporation
Authors: Zhou Bing , Jiang Xiao Hong , Rogachev A.V. , Shen Rui Qi
Published: December 2012

Diamond-like carbon (DLC) bilayer films with Cu interlayer were prepared on silicon substrate by direct-current and pulsed cathode arc plasma technique, and annealed at various temperatures in vacuum. Structure, morphology and mechanical properties of the bilayer films were investigated by Raman spectroscopy, Auger electron spectroscopy, scanning electron microscopy and atomic force microscopy, surface profilometer and Vickers sclerometer. The results show that Cu interlayer changes the bilayer microstructure, including the thickness and element distribution of diffusion layer, the relative fraction of sp3/sp2bonding and growth model of bilayer. A simple three-layer model was used to describe the interdiffusion between Cu and C layer. Cu interlayer could be more effective against graphitization upon annealing. Morphological characteristics of the films were studied by analyzing the surface features of substrate. Cu/DLC bilayer exhibits highly dispersed nano-agglomerates with smaller size on the surface due to low surface energy of Cu interlayer. The stress and hardness of the films were affected accordingly. Cu/DLC bilayer shows a relatively high hardness at low annealing temperature but the stress almost no change. By changing Cu interlayer and annealing temperature, excellent DLC films could be designed for the protective, hard, lubricating and wear resistant coatings on mechanical, electronic and optical applications.
Application of Photocatalytic Nanomaterials in Prevention from Sphaerothecaf uliginea In Vivo
Authors: Zhang Ping , Zhong Ru Gang , Cui Hai Xin
Published: December 2012

This study was conducted to investigate the efficiency of TiO2 photocatalytic nanomaterial as a novel environment-friendly disinfectant to control plant fungal diseases (Sphaerothecaf uliginea) by its photochemical sterilization ability in cucumber plants. Anatase nano-TiO2 sol, a neutral, viscous aqueous colloid of 1.4% TiO2, was synthesized by sol-gel method. Control efficiencies of nano-TiO2 sol in preventing from powdery mildew were measured by field experimental method with cucumber seedling naturally infected Sphaerothecaf uliginea. Results showed that spraying certain content of nano-TiO2 sol could form continuous and stable antibacterial films on blade surfaces which could not only significantly reduce lesion areas, disease incidences and disease indexes of powdery mildew but also make the leaves turn much greener. It was initially confirmed that nano-TiO2 sol could effectively delay and inhibit the development and pervasion of cucumber powdery mildew. These results indicate that nano-TiO2 sol can be developed as environment-friendly fungicide in preventing from plant disease developments.
Investigation on Properties of β-Ga2O3 Solid Films with Zno Nano-Interlayer
Authors: Kong De Min , Liu Ai Hua , Man Bao Yuan , Liu Mei , Guo Jin Jin , Hou Juan , Sun Zhen Cui
Published: December 2012

High-quality β-Ga2O3 films andβ-Ga2O3 /ZnO/β-Ga2O3 nano composite thin films were fabricated on the sapphire substrates in the high vacuum atmosphere by laser molecular beam epitaxy (LMBE). The lattice structure and optical properties of these films were characterized.With the increase of the sputtering time of ZnO target ,Photoluminescence spectrums and Raman spectrums of the β-Ga2O3 /ZnO/β-Ga2O3 nano composite films were shifted regularly . When the ZnO target was sputtered 30min , the stronggest peak of Raman spectrum was appeared at 267nm . Besides,the composition ofβ-Ga2O3 /ZnO/β-Ga2O3 nano composite film was described .
Investigation of Nanopowders Application in Metal Casting
Authors: Dimitrova Rossitza , Kuzmanov Pavel , Lazarova Rumyana , Manolov Valentin
Published: December 2012

The application of nanopowders in metal casting for modification and refining of microstructure as well as improving material properties is investigated.
BaTiO3 Nanopowders Hydrothermally Synthesized Using H2Ti3O7 Nanotubes and Nanorods
Authors: Zhou Hui
Published: December 2012

Perovskite BaTiO3 nanopowders are hydrothermally synthesized using H2Ti3O7 nanoentities, which themselves are also hydrothermally synthesized, as titanium precursors. The structure and morphology of the obtained BaTiO3 nanopowders are studied as functions of synthesis reaction time, using electron diffraction and electron microscopy. The morphology of the obtained BaTiO3 nanopowders is found to be determined by the morphology of the H2Ti3O7 precursors. Tubular structure can be maintained when H2Ti3O7 nanotubes are used as precursors. However, only BaTiO3 dendritic nanoparticles are obtained when using H2Ti3O7 nanorods instead as precursors. The morphology evolution is discussed in terms of nucleation on the surface of H2Ti3O7 followed by subsequent interdiffusion.
Electric Polarization Characteristic and Equivalent Circuit of the Pb(Zr0.95Ti0.05)O3 Nanoceramics
Authors: Chi Yuan Yuan , Zhang Chao , Wang Ying , Yu Da Shu
Published: December 2012

In this paper, the PZT nano-ceramics were prepared by an improved Sol-Gel method. This method was based on recording to A.S.Mischenko. TF Analyzer 2000 FE was used to measure the ferroelectric properties of the samples. The results show the change trends of the P-E hysteresis loops in different voltages, temperatures and frequencies. Impedance was tested by precision impedance analyzers 6500 series. With the use of the equivalent circuit to simulate the piezoelectric ceramic vibrator we can get a conclusion that in the 85 MHz-120 MHz the response of the sample can be represented with a RLC series resonant circuit. The resonant frequency of the sample is 97.12MHz, and the loss is very low. Compared with the general piezoelectric vibrator PZT 95/05 nano-ceramic is a low frequency capacitor with the capacitance tend to 0 F.
Catalytic Performance of Dimethyl Ether Combustion over La-Ce-Cu/Al2O3 Catalysts
Authors: Zeng Peng , Fang Yi Wen , Liu Xin , Wang Dong Lin , Hu Yuan , Sun Chang Yong , Song Yi Bing
Published: December 2012

kinds of Al2O3 were synthesized by using aluminum nitrate as the aluminum source, glucose, lactic acid and citric acid as templates respectively. It is showed that all Al2O3 were mesoporous materials due to their BET surface area results. The Al2O3-glu, synthesized by using glucose as a template, demonstrated fine pore shape, larger surface area and pore volume. The Ce0.1Cu0.9O1.1/Al2O3-glu catalyst exhibited good performance for dimethyl ether(DME) Combustion. La-doping can promote its catalytic activity. Over La0.4-Ce0.1Cu0.9O1.1/ Al2O3-glu catalyst, the DME combustion temperature(T10) was 493 K and the complete combustion temperature(T90) was 498 K. The life test result indicated its catalytic activity without any reduce even after 100 h reaction.
Study on Carbonization Thermal Dynamic Process of Coal Tar Refined Soft Pitch
Authors: Gao Li Juan , Zhao Xue Fei , Lai Shi Quan , Cheng Jun Xia
Published: December 2012

The carbonization thermal dynamic process of coal tar refined soft pitch(CTRSP) is studied by using a polarizing microscope with a heat stage. The pitch is preprated and it’s characteristics are that the soft point of 30°C, group compositions consist of 54.80% heptane soluble, 48.77% heptane insoluble but toluene soluble, 5.95% toluene insoluble but quinoline soluble and 0.08% quinoline insoluble, relative average molecular weight of about 292, average molecular structure of five- rings linear arrangement and cata-condensed structure. The polarizing microphotographs show that temperature of mesophase spherules beginning formation in the pitch is 440°C. To avoid speed of spherules generated is too fast, the temperature is decreased to 420°C at a rate of 10°C/min, and these spherules grow slowly at 420°C for 5 min. Then during temperature is raised to 500°C at rate of 3°C/min, these spherules change into bigger mesophase spheres because of absorbing matrix or colliding and coalescence between spherules. These bigger mesophase spheres absorb matrix or colliding and combine between bigger spherule again, finally because of gravity at 500°C, big mesophase spheres deform gradually, and develop into the semi-coke with streamline or clipper-built and/or coarse- fibrotic modality.
Effect of a Zwitterionic Copolymer on the Rheological Behavior of Aqueous α-Al2O3 Suspensions
Authors: Chen You Qiang , Zhang Xin Ni , Kong Qing Shan , Xia Yan Zhi
Published: December 2012

A zwitterionic copolymer has been synthesized and a common optimum concentration of dispersant for the stabilized Al2O3suspensions is found at 0.04wt%, which represents the adsorption saturation limit of polyelectrolytes at Al2O3–water interface at pH = 10. Based on the results from rheological measurements, involving the effect of dispersant concentration, a stable broader dispersant concentration range of 0.4wt% ~ 0.22wt% is observed for suspensions with solids loading ≤ 50vol%, a stable broader pH range of 7.0 ~ 11.2 for suspension with solids loading ≤ 50vol%, and a stable pH range of 1.2 ~ 2.0 for suspensions with solids loading ≤ 40vol%.
Self-Combustion Synthesis of AlN-SiC Solid Solution Powder in Air with Assistance of High-Energy Mechanical Milling
Authors: Li Zhuo , Jiang Jiu Xin , Wei Yan Ping , Yan Ming , Chen Yan Lin , Chang Ying
Published: December 2012

A very simple synthesis method of AlN-SiC solid solution powder, i.e. self-combustion of Al, Si3N4 and C mixture in the air only with assistance of high-energy mechanical milling, was proposed in the present work. The effect of compositions on the combustion behavior and the product was studied and the results showed that the amount of Al in the starting powder was the key factor affecting the combustion behavior, the phase assemblages and the morphology of products.
Moving Load and Fatigue Analysis of a Long Span High Speed Railway Bridge
Authors: Pipinato Alessio
Published: December 2012

Long span bridges, as cable-stayed and suspension bridges, have gained much popularity in recent decades for their structural shape, efficient use of materials and other optimal solution. A new phase is starting with main span lengths going over thousands of meter. As a matter of fact, small size substructures are required, the development of efficient construction techniques are growing on and faster progress in the FEM and design are evident. Ever since the dramatic collapse of the first examples of such long span structures, as the Tacoma Narrows Bridge in 1940, much attention has been given to the dynamic behavior of these structures. In this paper a moving load analysis performed on a cable stayed high speed railway bridge is presented together with a fatigue analysis of the cable stays, discussed according to the Italian code verification procedure.
Creep and Dilatancy Behavior of Rock Salt around Underground Caverns
Authors: Moghadam S. Nazary , Mirzabozorg H. , Noorzad A. , Nazokkar K.
Published: December 2012

In the present paper, the time-dependent behavior of a salt cavern was analyzed using finite element method. A viscoplastic model considering inelastic volume changes was utilized to describe the time-dependent mechanical behavior of rock salt. The model was then implemented in a finite element procedure to analyze the stress and deformation of rock salt around an underground cavern using an axisymmetric representation. Finally, finite element analyses results were compared with those obtained by a viscoplastic model neglecting inelastic volume changes.
Spatial Variability of Material Parameter and Bearing Capacity of Clay
Authors: Rahman Md Mizanur , Nguyen Hoang Bao Khoi
Published: December 2012

A stochastic analysis that incorporates spatial variability of material parameter of clay i.e. undrained shear strength, c within the finite element analysis was done. A smoother change of c between two neighbouring soil elements is expected than two elements at a distance apart, thus a spatial correlation length is used within the random field to describe the distance over which random values tend to be correlated. When the correlation lengths in horizontal and vertical directions are same, the soil elements can be described ‘isotropic’. Most of the previous studies investigated the effect of variation of c in terms of coefficient of variation, COV (standard deviation/mean) and the isotropic correlation length on bearing capacity. However, the correlation length of soil may not be isotropic as they may be deposited in layers i.e. correlation length in horizontal direction may be higher than that in vertical direction. Thus, this study investigated the effect of isotropic as well as anisotropic (in terms of correlation length) conditions and their lengths over a range of COV of c on the bearing capacity. The result of this study would help to understand the effect of soil anisotropy on bearing capacity.
Thermal Characteristics of Urban Surface Materials
Authors: Galli G. , Vallati A.
Published: December 2012

This paper studies the influence of different urban coverings (green areas or dry cover) on the urban microclimate. Different urban structures in a small area show different microclimatic behavior, depending on the thermophysical properties of the surface materials, in particular on the presence and extent of green areas. The research has been developed in downtown Rome in the summer period. In order to evaluate the impact of different urban envelopes, a typical urban square has been considered and analyzed systematically with the microscale climate model ENVI-met. A number of simulations has been performed with various kinds of surface covers and of vegetation and their effect on the air and soil temperatures and on the surface heat fluxes has been determined.
Effect of Cement-Sodium Silicate Grout on the Compressibility Parameters of Fibrous Peat
Authors: Sina Kazemian , Hossien Moayedi
Published: December 2012

The distribution of peat deposits can be found in many countries and peat-land constituents from 5 to 8% of earth land surface, where approximately 60% of the wetlands are peat. An increasing growth of the population leads to the necessity of peat-land utilization for development purposes. This article describes a laboratory study on the effect of sodium silicate on the compressibility parameters of peat, which are settlement, void ratio, compression index and coefficient of secondary compression. The effect of the sodium silicate and ordinary Portland cement on the compressibility parameter of peat is investigated through Rowe Cell consolidation test. At the end of this study, it is shown by increasing sodium silicate (within 2.5%), cement on treated peat, they are able to improve compressibility parameters of fibrous peat much more than conventional binders like pure cement.
Synthesis of Ca(OH)2 Nanoparticles Aqueous Suspensions and Interaction with Silica Fume
Authors: Daniele V. , Taglieri G. , Gregori A.
Published: December 2012

In this work, interaction at ambient temperature between silica fume and artificially produced Ca(OH)2 nanoparticles by two different methods was analyzed. Initial products and formed hydrated phases were characterized by several investigations including X-ray diffraction, thermal analyses, transmission and scanning electron microscopy. Synthesized Ca(OH)2 nanoparticles appeared regularly shaped and hexagonally plated, with side dimensions from 200nm to less than 20nm. Characterization analyses showed that, by reducing particles dimensions, calcium silicate hydrate phase formation was evident already after 7 day of hydration and a nearly complete consuming of free Ca(OH)2 after 28 days was observed. Besides, formed hydrate phases showed a highly wrinkled layer with marked crumple and rough-edge surfaces.
A New Image-Based Soil Deformation Measurement System
Authors: Zhao Yan Jiao , Wang Yu Xin , He Guo , Zhao Hong Hua
Published: December 2012

A Soil Deformation Measurement System using OPENCV library and FFTW library in C++ was developed in this paper. The system applied camera calibration based on neural network and Fasst Fourier Transform (FFT) cross-correlation algorithm for Particle Image Velocimetry (PIV). It is used to obtain soil deformation data, such as displacements, velocity and strain, and visualize the deformation. Experiments show that this system could acquire deformation data from soil images accurately, efficiently and continuously, which provides a strong proof that image processing technology has practical significance and application value in the research field of geotechnical engineering.
Intrinsic Ferromagnetism of the GaMnN Thin Films
Authors: Gao Xing Guo , Man Bao Yuan , Liu Mei , Yang Cheng , Chen Chuan Song , Sun Zhen Cui , Xu Shi Cai
Published: December 2012

The Mn-doped GaN (GaMnN) films on c-plane sapphire substrates were prepared by using Laser Molecular Beam Epitaxy (LMBE) at different base nitrogen pressure, followed by annealing in the ammonia atmosphere at 950 °C for 30 min, to study the original reason of the room-temperature ferromagnetism of GaMnN films. We found the crystalline quality was sensitive to the base nitrogen pressure during growth. X-ray photoelectron spectra (XPS) analysis confirmed that the Mn3+ and Mn2+ coexist in our samples. The room-temperature ferromagnetic behavior can be explained by double exchange. The ferromagnetism would be weakened by the nitrogen vacancies, which plays a role of donor.
Three-Dimensional Numerical Study of a Kitchen Extractor Adopting Nearby Pumping Method
Authors: Deng Jing , Hong Chong Guang , Wang Gui Quan , Sheng Hong Zhi
Published: December 2012

A third generation kitchen extractor adopting nearby pumping method is investigated by using the computational fluid dynamics software. The numerical results are close to the experiment results, which can be used for supporting the optimum design of the equipment. The important parameters such as the particular distributions of velocity, temperature, and species fraction are obtained, which can supply more information about the pumping mechanism of this equipment. It is concluded that the gas-film-jet-cover technology significantly contributed to guaranteeing the pumping effect. Furthermore, decreasing negative pressure of pumping circle and/or the increasing positive pressure of gas-film-inlet could increase the collection efficiency of the equipment. However, it is necessary to choose the most appropriate pressure for getting enough collection efficiency with relatively low energy cost and working noise.
Nonlinearity Errors in Heterodyne Interferometer: A Survey
Authors: Hu Hai Jiang , Hu Ju Ju , Ji Ying Hua
Published: December 2012

As the most important error source in the heterodyne interferometer, the nonlinearity errors reduce the measurement accuracy in the nanometric or picometric measurement. This survey states both the definition of nonlinearity errors and the cause of the errors. Moreover, two kinds of methods for detection and compensation of the nonlinearity errors are also discussed respectively in this paper.
Study of HAN-Based Liquid Propellant Droplet Evaporation in High-Temperature and High-Pressure Environments
Authors: Pan Yu Zhu , Yu Yong Gang
Published: December 2012

A high-temperature, high-pressure evaporation model for HAN-based liquid propellant droplet was built, which considered the multicomponent droplet, the unsteady heating-up, the droplet surface regression, and the nonideal gas effect. Based on the state equation of the real gas, a computation method applicable to high-pressure thermophysical property parameters was established. By use of the evaporation model, the evaporation process of a LP1845 droplet in the nitrogen atmosphere for pressures of 100–300 atm and temperatures of 1600 K was studied. The results indicate that the droplet radius increases firstly and reduces afterward as the evaporation goes on, and the reduction rate of the radius satisfies the D2 law. The droplet temperature rises rapidly at the beginning, then maintains stable gradually at an equilibrium value. When the ambient temperature remains constant, with increasing ambient pressure, the time to reach the equilibrium temperature lengthens, but the droplet lifetime shortens.
Topology Optimization of Applied Damping Material for Noise Control
Authors: Zheng Wei Guang , Lei Ying Feng , Huang Qi Bai , Li Chuan Bing
Published: December 2012

Applied damping material (ADM) is today widely used to reduce vibrations and sound radiations by damping out the resonant peaks of structures. The efficient use of ADM becomes more and more important from an optimization design view. In this paper, the potential of using topology optimization as a design tool to optimize the distribution of ADM on a vibrating plate to minimize its sound radiation is investigated. A solid isotropic material with penalization model is described based on a special interface finite element modeling for viscoelastic layer. Numerical analysis has been applied to demonstrate the validation of the proposed approach and shows that significant reductions of the sound radiation powers over a broadband frequency range are achieved by the optimized results.
Optimal Space Management Mechanism of Sharable Multi-Channel On-Chip Memory
Authors: Liu Cai Xia , Tian Xiao Qing , Zhang Zhi Bin
Published: December 2012

A kind of shared multi-channel on-chip memory CMP architecture is proposed in this article to efficiently support embedded applications. For the multi-channel on-chip memory being scarce resource, optimal space management mechanism of multi-channel on-chip memory is proposed including automatic space allocation strategy based on application parallelization mapping pattern and optimal space utilization scheme. ILP-model-based analysis of system performance verifies that the proposed optimal space management mechanism can deeply exploit the efficiency of multi-channel on-chip memory to improve system performance.
The Optimization of the Design of a Railway Wheel in Terms of the Acoustic Radiation under the Vertical Excitation
Authors: Zhang Bin , Liu Lin Ya , Shao Wen Jie
Published: December 2012

Railway wheel acoustic radiation takes a large proportion of the wheel-rail noise . This paper mainly focuses the ways to reduce railway wheel acoustic radiation to control wheel-rail acoustic radiation, and ultimately to reduce the railway environmental noise. In this paper, Optimization mathematical model of wheel acoustic radiation is built according to the wheel vibration and acoustic radiation theory, and obtaining the section optimization and acoustic radiation power of wheel by drawing up the genetic algorithm (GA) program and analyzing the acoustic radiation of the wheel according to Finite element and boundary element model. The result shows that the optimized acoustic power is reduced to some extent, even by 2dB at the peak point within 5000Hz. Since high-speed railways are put into operation in China, it has been more convenient for people to go out. However, serious railway environmental noise occurs by the way. The noise produced when the train is running affects not only passengers and working staff on the train, but also environment and residents around the railway. For this reason, to reduce the noise with proper measures is good for environment protection, sustained and healthy development of rail transportation as well. According to wheel-rail noise theory, the main approaches to reduce noise as follows:(1) Adopt damped wheel. (2) Add rubber isolation layer between tread and web of the wheel to form resilient wheel. (3) Optimize the wheel shape. (4) Reduce acoustic radiation efficiency of the wheel. This paper discusses how to reduce acoustic radiation of the wheel and railway environmental noise according to optimize the wheel shape by mainly analyzing the wheel of high frequency radiation noise.
Analysis of Particle Trajectory within Rotating Cylinders by DEM Simulation
Authors: Xie Zhi Yin , Feng Jun Xiao
Published: December 2012

Particle trajectory within rotating cylinders has been investigated in terms of radial positions by using the discrete element method (DEM). The dynamic information of particle groups has been obtained under a wide range of rotation speed by a method of particle marking and tracking. The results show a periodic way of inwards trend for particle motion within material bed. The period of particle motion is directly related to the rotation speed of the cylinder. However, the residence time of particles in the active layer shortens with periods, while that in the static zone prolongs. Moreover, the peak value of radial positions periodically decays, whereas the valley value periodically increases. This research laid a good foundation for further research on particle mixing and heat transport within the material bed in rotating cylinders.
An Improved K-ω Model for High Speed Flows
Authors: Liu Jing Yuan , Zhao Zeng Hui
Published: December 2012

An improved K-ω model, which allows for compressible corrections, is proposed in this paper. Numerical scheme was established utilizing the improved Total Variation Diminishing (TVD) scheme and applying implicit scheme to the negative source terms of the turbulence model. Hypersonic flat-plate boundary-layer flows and hypersonic compression ramp flows marked with separation, reattachment and shock/boundary layer interactions are then computed. Comparisons between the computational results, the experimental results and the semi-empirical formulations show that the compressible correction term of the K-ω turbulence model is a pressure-dilatation correlation. In addition, for flow with separation and without separation, calculation results of wall pressures, friction coefficients and wall heat transfer rate distributions using the improved model and established scheme agree better with the experimental results than that using the original K-ω model.
Implementing of Displacement Boundary Conditions of Element-Free Galerkin Method and its Applications Used in Fracture Mechanics
Authors: Cheng Gang , Wang Wei Dong , Zhang Dun Fu
Published: December 2012

The main draw back of the Moving Least Squares (MLS) approximate used in element free Galerkin method (EFGM) is its lack the property of the delta function. To alleviate difficulties in the treatment of essential boundary conditions in EFGM, the local transformation method and the boundary singular weight method, which are used in the reproducing kernel particle method, is combined with the element free Galerkin method. The computational method is given to analyze the stress intensity factors and the numerical simulation of crack propagation of two-dimentional problems of the elastic fracture analysis. The application examples reveal the effectiveness and feasibility of the present methods.
A New Slip Boundary Model of Liquid Flows
Authors: Song Fu Quan , Chen Xiao Xing
Published: December 2012

With the development of Micro Electro Mechanism System, the linear slip boundary of liquid flow has been often used. In this paper, some flows in different wettability boundaries were researched by Non-Equilibrium Molecular Dynamics (NEMD) simulation, and the characteristics of the slip length were discussed. The results show that: when liquid flow on the hydrophobic boundary, the slip length decreases with the external force increasing and the shear rate increasing near boundaries, the width of channel and the external force are not independent variables of the slip length, and the shear rate and the surface wettability are independent variables of the slip length. The slip length can be reduced by increasing the driving force for liquid flow in a channel. Finally, a new power law model of the slip boundary of liquid flow was derived.
Research on the Flow Boiling Characteristics of Water in a Multi-Furcated Tree-Shaped Mini-Channel
Authors: Yan Chen , Wei Chang , Zhang Shu Sheng
Published: December 2012

A new multi-furcated structure of tree-shaped mini-channel was proposed in this paper. Numerical simulation was conducted to analyze the flow boiling and bubble growth characteristics of water in the mini-channel. By using the constant wall temperature heating method, the model was divided into different sub-regions according to different wall temperatures. Typical bubbly flow and slug flow patterns were obtained through the monitoring of the boiling process. The simulation results showed that when the convective heat transfer dominated, the pressure drop maintained minor and stable; while the nucleate boiling dominated, the pressure drop increased significantly and fluctuated within a certain range. Moreover, with the increase of vapor quality, the heat transfer coefficient increased first and then decreased. It is also found that the geometric structure of the multi-furcated tree-shaped mini-channel had a great impact on the heat transfer characteristics, and simulation results agreed well with the theoretical values.
Application of Equipartition of Entransy Loss Principle in Heat Exchangers
Authors: Guo Chun Sheng , Du Wen Jing , Cheng Lin
Published: December 2012

The entransy loss minimization approach for the heat exchanger optimization design was established by Guo Z Y; the study based Guo Z Y’s works, found relationship between the entransy loss uniformity and the heat exchanger performance and the expression of the local entransy loss rate for heat convection was derived, numerical results of the heat transfer in a chevron plate heat exchanger and helix baffle heat exchanger show that the larger entransy loss uniformity factor appear in about Re=2000 and the entransy loss uniformity factor of chevron plate heat exchanges higher than helix baffle one.
Synthesis of Yttria-Stabilized Zirconia Particles by Flame Spray Pyrolysis Method
Authors: Zhou Xiong , Kong Wen Jun
Published: December 2012

This paper presented a novel synthesis method for yttria-stabilized zirconia (YSZ) by using the flame spray pyrolysis (FSP) method. Spherical and dense YSZ particles for thermal barrier coating were successfully synthesized by FSP from the nebulized precursor solution. XRD results revealed that the YSZ powder is only composed of tetragonal phase particles. Most particles are a few hundred nanometers in diameter and their sizes are mainly dependent on the concentration of the precursor solution, while flame condition has little effect. Particle size and morphology are greatly affected by the precursor composition. Particles synthesized from ethanol precursor solution are more uniform and better-defined than those from aqueous solution.
Thermodynamic-Dynamic Sea Ice Modeling under J Parallel Adaptive Structured Mesh Applications Infrastructure
Authors: Liu Xi Ying , Bai Tong Gui , Zhang Tao
Published: December 2012

Analyzing problems represented by partial differential equations numerically with modern high performance computers has become an important approach in research of earth science. In the work, a Sea Ice numerical Model under JASMIN (J parallel Adaptive Structured Mesh applications INfrastructure) (SIMJ for brevity) including thermodynamic and dynamic processes is implemented and an numerical experiment of 20-year integration with SIMJ has been performed. It’s found that the model can reproduce seasonal variation of Arctic sea ice well and implementation of parallel computing is flexible and easy. The ratio of time consumption is 1:1.16:1.48:2.45 with 8, 4, 2, and 1 core(s) respectively for one year integration on mobile workstation (Thinkpad W510) with Red Hat Enterprise Linux 5.4 and Portland group’s pgf90 9.0-1.
Numerical Analysis of a Heater with Conjugate Heat Transfer
Authors: Bai Y.G. , Zhang Y.G. , Liu Y.F. , Yang K. , Gao X.W.
Published: December 2012

This paper focuses on the influence of the conjugative heat transfer in a regenerative cooling structure. With proper numerical modelling by both finite element method and computational fluid dynamic method, the distribution of the temperature in the solid and coolant, the interfacial heat flux, and the stress state and the deformation of this cooling structure are obtained. These results show that the thermal equilibrium of the cooling structure can be achieved in a given flow condition. The present numerical method has significant benefits to solve the heat transfer between engine coolant and solid components.
Incomplete Rationality vs. Incomplete Strategy in Minority Game Model
Authors: Yao Xiao Bo , Han Chuan Feng , Wan Shao Long
Published: December 2012

Based on standard minority game, an Irrationality Agent Minority Game (IAMG) model is proposed, in which agents are less rational to make use of its strategy properly at each step. The control parameter of irrationality, pI, represents the probability of an agent acting irrationally, which could be explained with the personal defect. Like the incomplete (strategy) minority game (IMG) model introduced in our previous paper, this IAMG model also has three failsafe mode including (R0) random action, (R1) random strategy and (R4)”Back- to-Best”. The IAMG model can be explain with analytic equations similar with the IMG, and simulation results match the trend of the conclusion. Irrationality shows a great effect on system efficiency, and system efficiency reaches its top value at a smaller pIc than pIc in IMG. The IAMG and IMG model can be used to explain the deviation of some game theory simulations, and to understand the system performance with abundant agents of various characters.
Modern Technological Innovation Model, Uncertainties and Risk Management of Furniture Enterprises
Authors: Zhang Qiu Mei , Zhang Wei Mei
Published: December 2012

Modern technological innovation model of furniture enterprises mainly includes imitative innovation model, cooperative innovation model and independent innovation model. Furniture enterprises face a variety of technological innovation uncertainties, with the uncertainty management and risk management technology, innovators are able to recognize the uncertainties of technological innovation to achieve the transformation from the probability of unknown uncertainty to the probability of known uncertainty, as well as the transformation from uncertainty to certainty, this is beneficial to the furniture enterprises to improve the efficiency of technological innovation and the implementation of the innovation strategy.
Topic Research with Semantics
Authors: Wu Bing , Zhang Chen Yan
Published: December 2012

This study is a broadly review on the literatures from science citation index expanded (SCI-EXPANED) database, concerning topic research with semantic. The result indicates that the number of literature productions on this topic reaches climax of 4 in publication year 2012 and then followed by 2011 and 2007 of three papers respectively. The main research development country is China, and from the analysis of document type, articles accounts for 80%. Computer science acts as the main source title of this research. In general, the related research can be classified into application research and theory research. Multimedia, electronic document and general application are explored in application field, meanwhile text analysis, passage segmentation and semantic clustering are the main topics in theory research.
A SOMNN Model for Transport Risk Assessment of Hazardous Materials by Rail
Authors: Pan Ke , Guan Shouan
Published: December 2012

Railway siding for transport of hazardous materials is an important way in transporting of hazardous materials in China and they often result in catastrophic consequences for environment and society with a great deal of economic loss. Risk assessment for railway siding is an effective way to ensure its operational safety. This paper focuses on the application of self-organizing neural network (SOMNN) to assess the risk of the railway siding operational system and classify its risk factors. In this work, the system analysis method based on the characteristics of railway siding for hazardous materials is first used to establish the transport risk assessment index system. A comprehensive risk assessment model of railway siding has been developed with the SOMNN theory to improve present methods available for risk assessment of rail siding’s safety. A field case study about 15 railway slides for transporting of oil in Jilin broach center of China National Petroleum Corporation is undertaken so that the effectiveness of the proposed approach could be verified. The result is in line with the actual situation and indicates that this method used is feasible and rational. This model provides a new method for transport risk assessment of hazardous materials by rail. The method is also proved more efficient for both risk assessment and safety management. The work specified in this paper can be as reference to the assessment work in China.
Generating Singleton Fuzzy Models from Data with Interpretable Partition
Authors: Contreras Juan
Published: December 2012

This paper presents a new methodology for obtaining singleton fuzzy model from experimental data. Each input variable is partitioned into triangular membership functions so that consecutive fuzzy sets exhibit and specific overlapping of 0.5. The recursive least squares method is employed to adjust the singleton consequences and the gradient descent method is employed to update only the modal value of each triangular membership function to preserve the overlap and reducing the number of parameters to be estimated. Applications to a function approximation problem and to a pattern classification problem are illustrated.
An Algorithm of Maze Problem Based on Search
Authors: Cao Jian Li , Zhou Zhen
Published: December 2012

In this paper, a abstarct model is build for maze. Integrated maze was divided into many fragments, graphic traversal algorithm was used to classify those fragments into different category. By searching in the category, the wrong way of the maze can be eliminate, and the real way can be find easily.
Research on Asymmetry Information and Order Behavior in Order-Driven Market
Authors: Zhang Shao Jun
Published: December 2012

Investor’s order behavior directly reveals his willingness. Investors usually submit their orders according to their information. Different information will lead to diversity order behavior. In this paper, based on the asymmetry information, an investor’s order choice model in Chinese order-driven market is constructed, and then the role of asymmetry information on order submission strategy is investigated. By modifying the restriction on the duration of information, this paper discusses private information duration and uninformed investor’s learning process and investor’s optimal order strategy, and then concludes that when informed investor places market order, uninformed investor is more inclined to place limit order; only at the beginning of trading when informed investor places limit order, the uninformed buyer is more inclined to place market order.
Research on Command Process Modeling Method Based on IDEF Theory
Authors: Chen Z.H. , Zhu Y.H. , Fan X.
Published: December 2012

To study modeling for command activities process and command information process with the IDEF0 and IDEF3 method respectively. The purpose is to help staffs and commanders to understand and communicate by command process model, and lay foundation for the continuing transformation of the process of follow-up command and flexible reorganization under different operational conditions. Finally as an example, the electromagnetic spectrum management command process of joint operations is built to illuminate how to use the modelling method.
Norm-Profile Construction Using Splitting Neural Gas for Anomaly Detection
Authors: Liu Gui Song , Qu Hong , Yi Zhang
Published: December 2012

A neural gas network is a single-layered soft competitive neural network, which has many advantages for clustering analysis comparing to Kohonen's self-organizing map, K-means etc. This paper proposes a splitting neural gas algorithm (SNG). By initializing neurons splitting and finally deleting operations, the SNG can be used to characterize a certain class pattern effectively. We utilize the SNG to construct the profile of normal activities for anomaly detection in network security. Simulations are carried out using KDD CUP intrusion detection evaluation datasets. The experimental results showed that the SNG classifier can achieve the detection rate higher than 99% with a false positive rate lower than 1.6% and outperform many other recent supervised or unsupervised approaches.
Research on Key Technology of Intelligent Terminal Navigation Based on Augmented Reality
Authors: Zhang Hua , Yi Shan Zhen
Published: December 2012

The combination of AR and GIS is introduced into the intelligent terminal, the augmented reality technology was used to provide the navigation service on the real time video. This paper designs and realizes a smart and constricted prototype system to expand and popularize the traditional application of AR. It integrates the registration method, application of GIS and electronic compass of intelligent terminal. And it uses the method and simplified space scene model and the match method proposed in this paper. By using the standard interface of embedded system as a bridge and based on the computer graphics it provides real-time navigation service on the intelligent terminal. This develops and improves the traditional human-computer interactive processing mode.
Robust H∞ Output-Feedback Synthesis Optimal Control to Uncertain Time-Varying Delay System with Genetic Algorithm
Authors: Deng Jiu Ying , Wang Qin Ruo , Lee Wei Jen , Xiong Jian Bin
Published: December 2012

This paper explores the robust stability and H∞ control performance index of uncertain system with time-varying delay. The output feedback H∞ controller is constituted at the finite uncertain limit. The condition of delay-independence for the system with asymptotic stable and perturbation sustaining is derived as LMI formulation. The optimum control problem of uncertain time-delay system with H-infinite output feedback is presented. The stability and exogenous disturbance constraint synthesis is performed by chaos and genetic algorithm. The genetic algorithm based optimization approach is developed for extracting the upper bound of the performance index. Experiment results suggest that the H∞ output feedback control law is less conservative and possesses much high stabilization and optimization performance.
A Kind of Mathematical Method to Assess the Threat Degree of Aerial Targets
Authors: Tang Xue Song , Li Liu , Yu Zheng Gen , Lu Xiao Bing
Published: December 2012

Modern warfare aerial targets threat judgment is affected by many factors, these factors, there are some uncertainties, and make full use of the mathematical tools you can solve the uncertainty problem. Based on the fuzzy mathematics research, will it cleverly used to solve the threat judgment problems, effectively plays the superiority of fuzzy arithmetic, the specified air strike targets pose a threat to the conservation targets as well as the threat degree, and then depending on the threat degree sort the targets for the operational command decision-making to provide a more scientific and reasonable basis.
About the Maximum Transfer of Power in Time-Varying Linear Circuits
Authors: de la Sen M. , Alonso-Quesada S. , Garrido A.J. , Ibeas A.
Published: December 2012

This paper discusses the mathematical conditions of achievement of maximum power transfer from source to load in electric circuits where their basic elements (resistance, inductance and capacitance) are eventually linear and time-varying but not necessarily everywhere time-differentiable. This last concern is seen to be relevant for the inductive part of the circuit whose time- derivative, where it exists, plays the role of a resistor while it has an impulsive characterization at time instants where such a time-derivative does not exist. The power transfer degradation through time is also characterized related to the initial values of the circuitry provided that the source remains unaltered through time.