bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface Rolling Effect on Effective Short Fatigue Cracks Density for Railway LZ50 Axle Steel
Authors: Yang Bing , Zhao Yong Xiang
Published: June 2010

Surface rolling effect on effective short fatigue cracks density, which reflect the affecting capacity on the initiation firstly and then growth of the dominant short crack result finally in specimen failure, is experimentally studied by a replica technique. Two groups of smooth hourglass shaped specimens of LZ50 axle steel with/without rolled surfaces were tested. The crack density of surface rolled specimens was much lower than that of the other group. This indicates surface rolling technology having the effect of hardening surface layer material to introduce compressive residual stresses. The effect appears to restrain the short crack nucleation and propagation and then, to extend the fatigue life.
Methods for Device Applications Debugging
Authors: Zhao Fei , Xie Li Yang , Wu Ning Xiang
Published: June 2010

During device applications being debugged, communications with device are need. Combining with real device brings inconvenience on debugging, and even hides bugs. Techniques and methods for debugging device applications combined with virtual device are discussed in this paper, and already proved to be feasible and effective by projects’ decrease of cost and increase of efficiency.
Comprehensive Evaluation for Generalized Product Quality Based on Fuzzy Entropy
Authors: Chen Ya Zhe , Zhao Yang , Teng Yun Nan , Wen Bang Chun
Published: June 2010

With a view to improving product quality, the concept of generalized product quality is proposed and analyzed in depth to frame a comprehensive fuzzy evaluation system for generalized product quality, which includes all the constructional, operational and technological performance and function and takes account of the hierarchy and complexity of such an evaluation system. In the system the weighted value for each and every evaluation index is determined by combining entropy weight with subjective weight so as to make the evaluation more objective and scientific. Comparing with the method of comprehensive fuzzy evaluation, the evaluation system thus framed gets rid of the empirical subjectivity in determining index weight, thus enhancing the dependability of the weight, as a result, such an evaluation will be more reliable.
The Influence of Following Error of Servo System on Machining Precision for NC Machine Tool
Authors: Sun Xing Wei , Liu Wan Tao , Zhang You Jun , Wang Ke
Published: June 2010

The characteristic of servo system is an important data to influence the mechanical working properties of NC machine tool. In this paper, based on servo system characteristic, the cause of following error has been studied. It discussed the effect on machining precision of following error on part contour when machining circular contour. Then some calculation equations have been worked out. In order to reduce the following error, the method of compound control has been advanced in the last, and it has been proved to be a feasible way to reduce the influence of follow error on machining contour of NC machine tool.
Analysis of Hydraulic Lifting System and Design of Cylinder for the New 450t Schnabel Car
Authors: Li Yong Hua , Zhao Wen Zhong , Nie Chun Ge
Published: June 2010

The hydraulic lifting system of 450t schnabel car is more complex variable geometry mechanism. A simple technique for solving variable geometry mechanism is presented. The technique is based on energy conservation principle of hydraulic lifting process. The lifting principle and geometrical models are analyzed and formulated. The lifting pressure is calculated. The static strength design and bulking stability checking are introduced for cylindrical pressure cylinder. Results show that the maximum rated oil pressure meets cylinder lifting requirement, the static strengths of cylinder and piston reach lifting safety and reliability, and anti-bulking stability can be guaranteed under the loading and working conditions.
The Integrated Performability Analysis Architecture of the Computer Networks
Authors: Shi Jian , Wang Shao Ping , Wang Kang
Published: June 2010

Aimed at the challenges existing in current network performability research, this paper proposes an analysis architecture for network performability research, in which FMEA of the network, the availability model of the equipment, the topology analysis, the performance evaluation and the design of performability verification platform are integrated into together. This architecture assures accuracy of the performability analysis. According to the performance evaluation criterions, Capability-based performability, delay-based performability and PLR-based performability measures to the computer networks are suggested.
Cyclic Deformation Characters and Description of the Cast Steel for Chinese Railway Rolling Wagon Bogie Frames
Authors: Zhao Yong Xiang , Yang Bing
Published: June 2010

Cyclic deformation characters and description method are investigated to the grade B cast steel for Chinese railway rolling wagon bogie frames. Incremental step test method with 8 strain amplitude loading mode were employed. Results reveal that the material acts as non-Masing behaviour with a significant Bausinger’s effect and appears a slight cyclic softening. Great of dimples in the transient fracture district indicate that present material is ductile. Significant discrepancy between the monotonic and cyclic beaviour was revealed to indicate that there is different monotonic and cyclic deformation behaviour. The scattered cyclic stress-strain relations indicate that appropriate description for the cyclic deformation of present material should be a probabilistic modeling. And then, a probabilistic modeling with measurements of survival probability and confidence is developed to give a good description to the cyclic deformation behaviour.
Environment Risk Characteristics and Preventive Measures on Carbon Disulfide
Authors: Zhou Ji Hong , Wang Bin , Zhou Xiao Bin , Zhang Jian
Published: June 2010

At present, the environmental risk has become science foundation and one of important basis of the environmental risk management and environmental decision-making. This paper based on the chemical properties of carbon disulfide including physical and chemical properties, toxicity, explosive harms characteristics are studied and puts forward some preventive measures.
Model Based Automatic Test Research and Application
Authors: Zheng Wei , Xu Hai Tao , Guan Lu Shuai
Published: June 2010

With the rapidly development and widely acceptance of MDD(Model Based Design), MBT(Model Based Test) has been presented for many years, it matches test-first concept, has been widely accepted. In this paper, basic process of model based testing is presented firstly, after that, key technologies such as Model instruct, test case selection, test script running etc. are discussed. Actual test case with Specific Explorer is presented and test result analysis is presented.
Fuzzy Control of a Novel Type of Translational Meshing Motors
Authors: Wang Wei , Shan Xin Jian , Wei Shi Min
Published: June 2010

Owing to the nonlinear characteristic of a novel type of translational meshing motor with model uncertainties, a model reference control system which consists of a neural network and a fuzzy controller is used. The torque model is identified based on BP neural network, and then Fuzzy controller works as the controller. The description of the control system and training procedure of the neural network are given. The test results obtained for a torque control scheme suitable for the control of the motor are also presented to verify the effectiveness of the proposed nonlinear control scheme. It has been found that the fuzzy control system is able to work reliably.
The Research of Semi-Fragile Watermarking Algorithm Based on Dynamic Segmentation
Authors: Che Sheng Bing , Shu Xu
Published: June 2010

Based on human eye visual characteristics of brightness and texture, a new region segmentation method and quantitative formulas in transform domain were put forward. By dynamic quantization, the transparency of carrier images and the anti-attack capability of watermarking images were improved. And a new kind of adjustment operator was brought up, which adjusted the pixel value after inverse discrete wavelet transform.
Synthesis of Fluoro-Containing Superhydrophobic Cotton Fabric with Washing Resistant Property Using Nano-SiO2 Sol-Gel Method
Authors: Hao Li Fen , An Qiu Feng , Xu Wei , Wang Qian Jin
Published: June 2010

A superhydrophobic complex coating for cotton fabrics based on silica nanoparticles and new fluoroalkylsiloxane polymer was reported here. The complex thin film was prepared through sol-gel method using cotton fabrics as a substrate. Silica nanoparticles in the coating made the textile surface much rougher, and new fluoroalkylsiloxane polymer with reactive groups on the top layer of the surface lowered the surface free energy and enhanced the binding between silica nanoparticles and the fluoro-containing polymer. Textiles coated with this coating showed excellent water repellent property, and water contact angle (CA) increased from 138° on the pure fluoroalkylsiloxane polymer treated cotton fabric up to 156.5° on complex one. Moreover, this superhydrophobic complex coating possesses favorable washing durability and its CA still retain 106° after 20 times of soaping operations.
Simulation for Building Fault Swatches for Reciprocating Compressor
Authors: Lin Rui Lin , Liu Bo Yun
Published: June 2010

In the progress of fault diagnosis, the most difficult problem is how to build up the fault swatchs for diagnosis for the fault of reciprocating compressor. As for the working progress mathematic model of reciprocating compressor, some familiar faults are simulated in this paper. The method of building fault swatches of the Z-0.03/7 compressor is studied and tested. Using the fault swatches, the fault diagnosis of compressor has been carried on.
Application of Thermal Infrared Imagery in Human Action Recognition
Authors: Li Jian Fu , Gong Wei Guo
Published: June 2010

Human action recognition has been widely researched and applied in intelligent visual surveillance fields nowadays. Most work on action recognition has been visible-spectrum oriented over the past decade, while the persistence of visual surveillance system increases the demand for night-time action recognition. This paper deals with the problem of night action recognition using thermal infrared imagery. A novel algorithm based on the human action silhouettes energy histograms is proposed. The algorithm first makes use of the statistical background model and background subtraction method to extract the human action silhouettes, while calculating the silhouette energy images for the action sequences. Then, the histograms of oriented gradients are computed from the silhouette energy images. Finally, the human action is represented by the energy histograms features, and recognized by using the Euclidean distance and nearest neighbor classifier. An infrared human action database was built to provide a foundation for night action recognition. Experimental results using the infrared thermal action data show the effective of this method.
A Numerical Simulation of Hybrid Finite Analytic Method for Groundwater Pollution
Authors: Zhu Chang Jun , Wu Li Ping , Li Sha
Published: June 2010

With the development of social, economic, groundwater pollution is becoming a concern in our country. In view of the defiency of traditional finite difference method, in this paper, a proposed hybrid finite analytic method was adopted to solve the problem about groundwater pollution. Testing with some examples and contrasting with finite difference method, we can get the conclusion that the hybrid finite analytic method is available.
A Meme-Gene Co-Evolution Algorithm for the Image-Matching Question
Authors: Sun Guo Xi , Peng Zhi Ping , Cui De Long
Published: June 2010

The paper introduces the current research status of image-matching question and proposes a new improved genetic algorithm. It adopts a meme-gene co-evolution technique for the improvement of engineering performance. The simulation results show the improved GA has the higher stability and the better graph than the SGA.
Dynamic Modeling of Tree Growth in a Nursery Greenhouse Using MATLAB and Simulink
Authors: Yang Zi Dong , Bai Yu
Published: June 2010

The GUESS (Greenhouse Use of Energy Seedling Simulator) model is a lumped-parameter coupled dynamic simulation combining a carbon-based process model of seedling growth with a heat/mass transfer model of the greenhouse envelope. GUESS was created to provide nursery managers and engineers a tool to assess the impact of climate control decisions upon energy use and seedling growth rate. The source code for GUESS was written using Simulink and MATLAB. A test case was set up to validate the model. And experimented with different lighting targets to see which one offered the most growth per unit energy cost. The model was parameterized for Douglas fir production in Corvallis, OR Seedlings were started at 0.57g d.w and were harvested at 1.7g d.w Temperature regulated to 68.5±6.3°F Growth rate could be highly sensitive to carbon content conversion as well.Models can be very useful as simulation tools, but their utility depends highly upon the data used to parameterize them.
On the Oriented Growth and Optical Property of ZnO Thin Films Deposited on NaCl (001) Substrate by Ion Beam Sputtering
Authors: Mao Shih Wei , Shen Jung Hsiung , Gan Der Shin , Huang Hsing Lu , Yeh Sung Wei
Published: June 2010

Temperature dependent oriented growth of ZnO thin film deposited on NaCl (001) substrates using ion beam sputtering was studied by transmission electron microscopy (TEM). Thin films showing a texture due to parallel epitaxy with NaCl (001) as deposited at 100 oC, whereas thin films deposited at 400 oC can form a texture. The microstructure and the epitaxial relationship with the NaCl (001) plane were studied by a high-resolution TEM. The possible causes for the orientation changed with temperature are discussed. The optical transparency of the nanofilms grown from room temperature to 400 oC was measured.
Research on Distributed Intrusion Detection Model Based on Information Fusion
Authors: Du Ping , Xu Wei
Published: June 2010

The research actuality of Intrusion Detection System(IDS) were analyzed, Due to the defects of IDS such as high positive rate of IDS and incapable of effective detection of dispersed coordinated attacks on the time and space, the ideas of the multi-source information fusion were introduced in the paper, a multi-level IDS reasoning framework and prototype system were presented. The prototype adds analysis engine to the existing IDS Sensor, We used Bayesian Network as a tool for multi-source information fusion, and we used goal-tree to analyze the attempts of coordinated attacks and quantify the security risk of system. Compared to the existing IDS, the prototype is more integrated and more capable in finding coordinated attacks with lower false positive rate.
E-Government Knowledge Navigation Based on Topic Maps
Authors: Zhai Jun , Song Ya Mei , Li Jian Feng
Published: June 2010

Topic Maps (TM) are standardized by ISO 13250 for the pur¬pose of semantic annotation of WWW resources. This paper presents the knowledge navigation system for E-Government information portal based on Topic Maps technology, including four layers: information resources layer, knowledge layer, information navigation server layer and application layer. The method of constructing topic maps from domain ontology is discussed. The knowledge layer is abstracted from large quantities of distributing heterogeneous municipal information resources by using TM. Navigation scope is built on the knowledge level which enlarges the navigation unit granularity and quantity of receiving information, shortens the navigation routing, improves the efficiency of navigation, and achieves the intelligent information retrieval. The research is valuable in E-Government and knowledge navigation.
Network Security Risk Assessment Method Research Based on Fuzzy Analytic Hierarchy Process
Authors: Yu Zhi , Xu Xiang , Wu Xian Jie
Published: June 2010

Aiming at the problem of complexity and uncertainty factors existing in network security risk assessment process, an analysis method based on Fuzzy Analytic Hierarchy Process is proposed in this paper. By the theory of fuzzy mathematic, this method establishes the network risk assessment model and constructs fuzzy judgment matrix to determine index weight of each level factor. The example of calculation results shows that the method is feasible and effective.
Booth Array Multiplier Based on Adiabatic Computing
Authors: Li Hong , Ye Li Fang , Hu Jian Ping
Published: June 2010

Power-efficient multipliers are essential for low-power signal processing hardware and embedded digital system since they have high switching activity and contain large node capacitances, resulting in large power dissipation. This paper presents an adiabatic Booth array multiplier based on PAL-2N circuits. It is composed of Booth encoders, a multiplier array containing partial product generators and 1-bit (half and full) adders, and a final carry-lookahead adder. Full-custom layouts are drawn. The energy and functional simulations have been performed using the net-list extracted from their layouts. The simulation results show that the adiabatic Booth array multiplier attains large energy savings, compared with its counterpart without the booth encoder.
Object Location of a Humanoid Robot Based on Stereo Visual
Authors: Du Qin Jun , Liu Yu Bin , Zhang Xue Yi
Published: June 2010

Object location is one of the most important technology in robotics. This paper discuss a humanoid robot visual system, two computers are embedded in the humanoid robot in order to ensure real time localization of a moving object, computers are linked with each other through memolink communication module. One computer is responsible for processing the object images, estimating and predicting the states of the object; another one is used to control humanoid robot motion. Experiments show the effectiveness and robustness of the humanoid robot system.
An Improved Supercapacitor Model and its Parameter Identification for Wind Power Flow Optimization and Control System
Authors: Zhao Yan Lei , Li Hai Dong , Zhang Hou Sheng , Liu Xue Ting
Published: June 2010

According to the operating characteristics of the wind power flow optimization and control system, an improved supercapacitor euqivalent circuit model is proposed, which characterizes termimanl behavior of the supercapacitor in the time ranges from several seonds to several minutes as well as the influence of lekage current in hours range. By the method of circuit analysis, parameter identification of the model is deduced in detail. The smilation and expriment results indicate the model and its parameter idenfication method proposed in the paper are feasible and effective.
UCS Neural Network Model for Real Time Sand Prediction
Authors: Oluyemi Gbenga Folorunso , Oyeneyin Babs Mufutau , Macleod Chris
Published: June 2010

Exploration and production activities have moved into more challenging deep-water and subsea environments. Many of the clastic reservoirs in these environments are characterized by thick overburden, HP-HT and largely unconsolidated formations with challenging sand management issues. For effective overall field/reservoir management, it is crucial to know if and when sand would fail and be ultimately produced. Field-life sanding potential evaluation and analysis, which seeks to evaluate the sanding potential of reservoir formations during the appraisal stage and all through the development to the abandonment stage, is therefore necessary so that important reservoir/field management decisions regarding sand control deployment can be made. Recent work has identified Unconfined Compressive Strength (UCS) as a key parameter required for the evaluation and analysis of sanding potential of any reservoir formation. There is therefore the need to be able to predict this important sanding potential parameter accurately and in real time to reduce the level of uncertainties usually associated with sanding potential evaluation and analysis. In this work, neural network coded in C++ was trained with log-derived petrophysical, geomechanical and textural data to develop a stand-alone model for predicting UCS. Real-time functionality of this model is guaranteed by real time data gathering via logging while drilling (LWD) and other measurement while drilling (MWD) tools. The choice of neural network over and above other methods and techniques which have been widely used in the industry was informed by its ability to better resolve the widely known complex relationship between petrophysical, textural and geomechanical strength parameters.
Review of Pc-Sw Data for Network Model Validation
Authors: Olafuyi O.A.
Published: June 2010

Advances in micro-CT imaging of porous materials provide the opportunity to extract representative networks from the images. This improves the predictive capability of pore scale network models to predict multiphase flow transport properties. However, all these predictions need to be validated with laboratory experimental data. The experimental data for such validation may either be from the literature or newly conducted laboratory experiments on same outcrops.
This paper presents the review of some of the available Pc – Sw experimental data available in the literature for validating the predictions made by network models.
Elastohydrodynamic Analysis of an Offset Journal Bearing Lubricated with Couple Stress Fluid
Authors: Chetti B.
Published: June 2010

This work is an investigation of the performance characteristics of an offset journal bearing lubricated with a fluid with couple stresses taking into consideration the elastic deformation of the liner. The couple stresses might be expected to appear in noticeable magnitudes in liquids containing additives with large molecules. The modified Reynolds equation has been solved using the finite difference method. Load carrying capacity, attitude angle, side leakage and friction coefficients are determined for various values of couple stress parameter of a rigid and deformable bearing. It is found that, the static characteristics of journal bearings lubricated with couple stress fluids are improved compared to journal bearings lubricated with Newtonian fluids. It is concluded that, the elastic deformation of the bearing has significant influence on the bearing characteristics.
Finite Element Method of Predicting GSM Radio Power Received in a Macrocell Environment
Authors: Emagbetere J.O. , Edeko F.O.
Published: June 2010

The numerical solution of the partial differential equation (PDE) of the received signal strength from fixed transmitting stations as derived from Maxwell’s wave equation is presented in this paper. The received signal strength level (RSSL) at a defined distance from a source point (base transceiver station) was simulated for two real environments described as Sites 1 and 2. The values of RSSL were taken at different nodes and at different radial directions away from the source point using the Finite Element Method (FEM) tool of the MATLAB package. The hexagonal geometry with no describing function was assumed for the cell. A 3-D model of the power received versus distance was obtained, and the numerical solution of the model presented. The numerical results obtained from the 3-D model were compared with the results of the drive test conducted in Sites 1 and 2 for functional GSM radio networks in the areas. The suitability of the method was justified for the two sites with a 5.55dB standard deviation of error for network A in Site 1 and 8.36dB and 3.40dB standard deviations of error for networks A and B respectively for Site 2.
Review on the Hall-Petch Relation in Ferritic Steel
Authors: Takaki Setsuo
Published: June 2010

Yielding of polycrystalline low carbon steel is characterized by a clear yield point followed by unstable Lüders deformation and such a yielding behavior is taken over to fine grained steel with the grain size of 1μm or less. Yield strength of ferritic steel is increased with grain refinement standing on the Hall-Petch relation. The following equation is realized up to 0.2μm grain size in the relation between yield strength y and grain size d: y [MPa]= 100+600×d[μm]-1/2. In low carbon steel, it might be concluded that the Hall-Petch coefficient (ky) is around 600MPa•μm1/2. However, the ky value of interstitial free steels is substantially small as 130-180MPa•μm1/2 and it can be greatly increased by a small amount of solute carbon less than 20ppm. It was also cleared that the disappearance of yield point by purifying is due to the decrease in the ky value. On the other hand, the ky value is changeable depending on heat treatment conditions such as cooling condition from an elevated temperature and aging treatment at 90°C. These results suggest the contribution of carbon segregation at grain boundary in terms of the change in the ky value. On the contrary, substitutional elements such as Cr and Si do not give large influence to the ky value in comparison with the effect by carbon.
Texture and Substructure Development during Post-Dynamic Softening in Ni-30%Fe Austenite
Authors: Beladi Hossein , Cizek Pavel , Hodgson Peter
Published: June 2010

The texture and substructure development during post-dynamic annealing of an austenitic Ni-30%Fe model alloy after complete dynamic recrystallization was investigated using electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM). A novel mechanism of metadynamic softening is proposed based on the experimental investigation of the grain structure, crystallographic texture and dislocation substructure evolution. The initial softening stage involved rapid growth of the dynamically formed nuclei and migration of the mobile boundaries. The subboundaries within DRX grains progressively disintegrated through dislocation climb and dislocation annihilation, which ultimately led to the formation of dislocation-free grains, while the grain boundary migration gradually became slower. As a result, the DRX texture was largely preserved throughout the annealing process.
Mechanical Properties and Metallurgical Qualities of High Aluminum Content Magnesium Alloys Fabricated by Twin-Roll Casting
Authors: Watari Hisaki , Nishio Yoshimasa , Suzuki Mayumi , Nakamura Ryoji , Koga Nobuhio , Davey Keith
Published: June 2010

This paper describes the twin-roll casting technology of magnesium alloys that contain relatively high weight ratios of aluminum, such as AZ91, AZ101 and AZ111. The magnesium alloy sheets were cast by a horizontal twin roll caster to manufacture relatively high-strength Mg alloys with high aluminum content. The influences of such process parameters as casting temperature and roll speed were ascertained. The microstructures of cast magnesium alloy sheets are observed to investigate the effects of roll-casting conditions on crystal growth in the cast products. It was found that Mg alloys with high aluminum content can be fabricated at a roll speed of 15 m/min with a horizontal-roll caster. The grain size of the manufactured wrought magnesium alloy sheet was about 10 micrometers due to rapid solidification in the proposed process.
Modeling of Microstructure Development in a Continuously Solidified Immiscible Alloy
Authors: Zhao Jiu Zhou , Li Hai Li , Wang Qing Liang
Published: June 2010

A model is developed to analyze the microstructure evolution in a continuously solidified immiscible alloy. The model takes into account the common actions of the nucleation and the diffusional growth/shrinkage of the minority phase droplets, the spatial phase segregation and the convections of the melt. The microstructure formation in a continuously solidified immiscible alloy is calculated. The numerical results demonstrate that the convective flow has great effect on the microstructure evolution. The convective flow against the solidification direction causes an increase in the nucleation rate while the convective flow along the solidification direction causes a decrease in the nucleation rate of the minority phase droplets. The convective flow leads to a more nonuniform distribution of the minority phase droplets in the melt. It causes an increase in the size of the largest minority phase droplet and is against the obtaining of the immiscible alloys with a well dispersed microstructure.
Numerical Simulation of Bubbles Expansion and Solidification of Metal Foams
Authors: Hao Hai , Diop Mouhamadou , Yao Shan , Zhang Xing Guo
Published: June 2010

Metal foams have both structural and functional properties, offer advantages in different fields such as automotive and aircraft etc., and thus gain more and more technical interest. In this study, a computational model is presented which allows the numerical simulation of the bubble expansion and solidification during metal foaming processes. Mathematical modelling of the different relevant physical properties and effects during the metal foam expansion and solidification is discussed in this paper. This model considers the broad variety of the complex boundary conditions, the simple and multiphase fluid flow with complex geometries, the stabilization of the foams, and the mutual interactions between the bubbles. The Navier-Stokes equation is applied to elucidate the fluid flows in the liquid and in the mushy zone. And the diffusion equation for the hydrogen transport, the distribution functions of the temperature, the density and kinetic equations are also be proposed and discussed.
Grain Fragmentation in Equal Channel Angular Pressed Copper
Authors: Gu Cheng Fan , Tóth László S. , Beausir Benoît , Williams Tim , Davies Chris H.J.
Published: June 2010

A comparative experimental and simulation study of oxygen-free high conductivity copper produced by equal channel angular pressing (ECAP) one-pass has been carried out by using electron backscatter diffraction (EBSD) and a recently proposed grain refinement model. The grain size and misorientation distributions were extracted from the EBSD measurements. It was found that the microstructure in the ECAP deformed copper was much more refined on the TD plane. The grain size observed experimentally can be fairly well predicted by the grain fragmentation model.
Statistics for Quantifying the Mechanical Properties of Nanomaterials
Authors: Lu Chun Sheng
Published: June 2010

In the paper, the up-to-date advances in the statistical analysis of nano-mechanical measurements are briefly reviewed. It is shown that, by means of statistical methods such as a minimum information criterion, a better statistical model can be selected for quantifying the intrinsic mechanical properties of nanomaterials or extracting the optimal information from those imperfect experimental data obtained with recently available nano-mechanical testing techniques.
Study on Casting Roll during Twin-Roll Casting of Thin Strip
Authors: Zhang Xiao Ming , Jiang Zheng Yi , Wei Dong Bin , Liu Xianghua , Wang Guo Dong
Published: June 2010

In twin-roll thin strip casting, the temperature of casting roll affects the roll thermal stress, and influences the thermal deformation, the generation of roll surface cracks, the strip shape and the service life of casting roll. In this paper, the features of the casting roll materials have been analysed, the effects of the clad materials and thickness on temperature field of the casting roll have been simulated and discussed. The developed temperature model of casting roll is helpful in optimising processing parameters and the design of casting roll during twin-roll thin strip casting.
Rigid-Plastic Finite Element Analysis of Cross Wedge Rolling
Authors: Chen Dyi Cheng , You Ci Syong , Lai Gua Nying , Ji Syue Cheng
Published: June 2010

In the cross wedge rolling process, many factors must be controlled to obtain the required plastic strain and desired tolerance values. The major factors include the wedge relative velocity, the forming angle, the spreading angle, and sectional reduction. This paper uses rigid-plastic finite element (FE) DEFORMTM 3D software to investigate the plastic deformation behavior of an aluminum alloy (A7075) workpiece as it is processed for cross wedge rolling. This study analyzes the effective strain, the effective stress, and the X-axial load distribution of the workpiece under various rolling conditions. Furthermore, using simulation software to analyze the changes to the microstructure by the rolling process, this study presents analytical results that confirm the suitability of the current finite element software for cross wedge rolling.
Research on Design Method of Polygonal Roll Pass for Stretch Reduced Seamless Tubes
Authors: Li Sheng Zhi , Bao Hai Yan , Zhang Zhi Chao , Li Yang Hua , Long Gong Ming
Published: June 2010

the aid of commercially available software MSC.SuperForm, a 3-D finite element model has been established to simulate the rolling process of steel tubes on the stretch reducing mill (SRM) with group centralized differential drive in certain factories. A special effort was made to analyze the fluctuation of transverse wall thickness uniformity. It was found that the wall thickness of each stand was accumulated in the original pass 50°~60° along the circumferential direction, which caused the formation of the inner hexagon defects and worsen. In view of this, this paper proposes a modified roll pass design method which uses the interactive technology of CAD graph curve and MATLAB equation. By means of decreasing the lateral curvature of roll pass contour curve to enlarge the contact length between the tube and groove, also the rolling process using the new pass system were simulated and analyzed. The results indicate that the design of such polygonal roll pass can be effective in improving the inner hexagon defects.
Research on Winding Technology of Thin Helical Tube of Pd-Y Alloy
Authors: Ma Guang , Zheng Jing , Li Yin E , Wang Yi
Published: June 2010

The thin helical tube of Pd-Y alloy was mainly used to high purity hydrogen preparation. The physical phenomenon was comprehensively considered during the winding process on the thin helical tube of Pd-Y alloy. Analysis the reason of wrinkling and depression is emerged on the inner of thin helix tube during the winding process on the thin helical tube of Pd-Y alloy. Stress state was analysed on the winding process of the thin helical tube through the elastoplastic finite element method; the stress distribution law was obtained. And then, the stress state was comparative studied on the thin helical tube of Pd-Y alloy by different tension action, the control conditions of tension was presented, it was between sixty-five to seventy-five Newton. Therefore, the numerical simulation study provided theory basis for the process control of the thin helical tube’s manufacture. It was no wrinkling and depression by winding simulation test on the thin helical tube of Pd-Y alloy, satisfies requirement of using.
First-Principles Calculations of C2H4 Adsorption on Pd Surface Stacked on Fcc-Au
Authors: Taguchi Noboru , Tanaka Shingo , Akita Tomoki , Kohyama Masanori , Hori Fuminobu
Published: June 2010

We performed first-principles calculations of stable atomic structure and partial density of states (PDOS) analysis of Ethylene (C2H4) adsorption on Pd(100) surface stacked on fcc-Au using the projector augmented-wave (PAW) method. In case of Pd overlayers on the Au(100) substrate, from the analysis of PDOS around surface, highest occupied states become sharpen compared with the case of C2H4 adsorption on Pd monometallic slab surface in both di- and  adsorption model.
The Effect of the Doping Profile in Aluminum Back-Surface-Field on the Electronic Properties of c-Si Solar Cells
Authors: Zhou Ji Cheng , Chen Yong Min
Published: June 2010

The electronic properties of the solar cells were greatly influenced by the aluminum atomic concentration in Al-BSF region under that the Al-BSF is doped heavily. The effects of the dopincg profile in heavily-doped Al-BSF on electronic properties of n+pp+ monocrystalline solar cells were investigated by PC1D. The results show that the electronic properties of solar cells are almost independent of the doping profile of the Al-BSF, but are more or less affected by the BSF profile if the solar cell back surface is passivated well with the BSRV less than ~105cm/s. When the sheet resistance is about between 5 and 30Ω/□, the conversion efficiency can reach the maximum value. And the optimum thickness of Al-BSF is about between 10~15μm.
Investigation on the Mechanical Properties of Molybdenum-Doped Zinc Oxide Transparent Thin Film by Sputtering Technique
Authors: Chen Tao Hsing , Hsieh Po Tsung , Huang Chao Yu , Wang Ji Quan , Chuang Ricky Wen Kuei
Published: June 2010

Zinc oxide thin films were prepared on the glass substrate by rf-magnetron sputtering technique and their structural, optical, and mechanical characteristics were then investigated. As the SEM images have revealed, the average grain size of ZMO thin film are influenced by pressure and sputter power, and the average value of the grain size is about 30~50 nm. The EDS analysis also revealed a successful doping of Mo in ZnO thin film. The transmittance property of ZMO thin film exhibited an excellent transparency in the visible range, where the transmittance was about 90% for ZMO film with Mo. Moreover, good transmittance was also demonstrated in the range of 350nm to 400nm (UV regime). Finally, the nano-mechanical properties of ZMO thin films were investigated using a nanoindentation technique. The corresponding result would show that the Young’s modulus and hardness both increased with decreasing pressure.
Effect of Ultrasonic Surface Peening on Fatigue Property of 7B04 High Strength and Toughness Aluminum Alloy
Authors: Zhu Qi Fang , Sun Ze Ming , Ma Tong Da , Klimenov Vacily A. , Borozna Viacheslav , Zhu Bao Hong
Published: June 2010

This paper discusses the influence of ultrasonic surface peening on the fatigue property of 7B04 high strength and toughness aluminum alloy. The results showed that a nano-layer of 10-20 μm was formed after ultrasonic surface peening. This nano-layer had a gradient structure with grain size of 10 to 50nm. Further, the ultrasonic surface peening process created residual compressive stress of 200MPa in this nano-layer. This stress caused micro surface cracks to be compressed or closed . Consequently, after ultrasonic surface peening the fatigue life of 7B04 alloy was extended to 5 times.
Electrochemical Corrosion Behaviors Using Double Glow Forming TiN Multi-Permeation Layer
Authors: Liu Yan Ping , Xue Jin Xiang , Han Pei De
Published: June 2010

A new process technique that TiN permeation layer consisted of diffusion and deposition layer was synthesized on the surface of mild carbon steel has been firstly introduced, mainly according to plasma point discharge, hollow cathode effect and reactive vapor deposition technique. The surface appearance of this layer formed was uniform, compact and fine TiN cellular structure, a diffusion transitional region existing between the deposition layer and substrate. The surface texture was TiN deposition layer + TiN + Ti solid solution diffusion layer. From surface to inner Ti and N elements appeared graded distribution. This paper also mainly investigated the electrochemical corrosion behaviors of this multilayer. The polarization curves of specimens in 10% H2SO4 corrosive media were measured. The eroded surface morphologies were also surveyed by SEM. The results indicated that the erosion resistance of multi-permeation layer was increased many times than PVDTiN and a mild steel substrate, and almost equaled to that of compound process TiN layers.
Structure and Diffused Ferroelectric Properties in Ba(Ti0.8Sn0.2)O3 Ceramics
Authors: Gui Dong Yun , Hao Hua , Sun Yue , Cao Ming He , Yu Zhi Yong , Xue Li Hui , Liu Han Xing
Published: June 2010

Temperature-dependent Raman scattering, dielectric properties, and Impedance spectra have been carried out on Ba(Ti0.8Sn0.2)O3 ceramic sample. The number of modes observed for the compositions of cubic symmetry is more than that predicted by group theory, and the A1(TO1) and E(TO2) modes become Raman active below the critical temperature (around 300K) in the lower frequency region. This gives evidence that there are some deviations of the local structure from the average global symmetry. Moreover, The characteristic of A1(TO3) mode is confirmed be associated with the diffused dielectric properties. Impedance/modulus analyses indicate that a third resistance-capacitance (RC) response is present in the sample, in addition to the grain and grain-boundary RC elements above 573K. Thus, it probably inferred that the existence of inter- and/or intra-granular surface layers associate with the abnormal dielectric properties, which is different from the normal ferroelectrics. Variation of bulk ac conductivity as a function of temperature shows that Ba(Ti0.8Sn0.2)O3 follows the classical Arrhenius relation.The results show that the activation energy of grains and grain boundaries are 0.61 and ~1.08 eV, respectively.
Preparation of Magnesium Carbonate Whisker by Using Magnesite Tailings
Authors: Wang Nan , Li Yue Yuan , Ni Hong Wei
Published: June 2010

Magnesium carbonate whisker was prepared by thermal decomposition of Mg(HCO3)2 solution that was prepared through hydration and carbonation of light burnt magnesia derived from magnesite tailings. The effects of thermal decomposition conditions on the morphology of magnesium carbonate crystal were investigated. Magnesium carbonate whiskers were successfully prepared when a kind of soluble magnesium salt was added, and magnesium carbonate whiskers with the length of 20 to 60μm and aspect ratio of 10~20 were obtained under the condition of 50 °C thermal decomposition temperature and 200 rpm stirring intensity.
Optical Properties of Transparent MgO-Doped Alumina Fabricated by Spark Plasma Sintering
Authors: Kim Byung Nam , Hiraga Keijiro , Morita Koji , Yoshida Hidehiro
Published: June 2010

The microstructure and optical properties are investigated for MgO-doped alumina fabricated by spark plasma sintering at temperatures between 1100 and 1550 °C. The MgO doping renders the microstructure less sensitive to the sintering temperature by suppressing grain growth, whereas it has no significant effect on the densification of alumina and resultantly no effect in enhancing the total forward transmission. The value of the total forward transmission can be used as an indirect measure of the slight change in density.
Nanotube and Micropore of Ti Alloy Systems for Biocompatibility
Authors: Choe Han Cheol
Published: June 2010

Micropore and nanotube formation on the Ti oxide are important to improve the cell adhesion and proliferation in clinical use. In this study, nanotube and micropore of Ti alloy for biocompatibility have been investigated using FE-SEM and XRD. Ternary alloys were prepared by using high purity sponge Ti Ta, Zr and Nb sphere (99.95% wt.%). Two-step anodizing was used for surface modification of the titanium alloys. Micropore formation was first performed using a potentiostat in 1 M H3PO4 electrolyte and nanotube formation was performed in 1M H3PO4 + 0.8wt% NaF solution by using a potentiostat. The two-step anodizing process is an efficient method for forming micropores and nanotubes on the surfaces of ternary titanium alloys, and the morphology of micropore and nanotube is dependent on the alloying element and composition of ternary alloy.
Self-Accommodation Morphology in Ti-Nb-Al Shape Memory Alloy
Authors: Inamura Tomonari , Hosoda Hideki , Kanetaka Hiroyasu , Kim Hee Young , Miyazaki Shuichi
Published: June 2010

The self-accommodation microstructure of a -titanium shape memory alloy (SMA) was investigated by conventional transmission electron microscopy (CTEM) observation. There were two distinct minimum units for the self-accommodation microstructure. One was the V-shaped pair of two habit plane variants that were bounded by the {111}TypeI twin as reported in some previous studies. The other was the bundle of the two habit plane variants that were bounded by the <211>TypeII twin. The later one had not been recognized as the self-accommodation microstructure in -titanium SMAs.
Evaluation and Control of Crystallographic Alignment of Biological Apatite Crystallites in Bones
Authors: Nakano Takayoshi , Ishimoto Takuya , Lee Jee Wook , Miyabe Sayaka , Ikeo Naoko , Fukuda Hidetsugu
Published: June 2010

Our group focused on the preferential degree of biological apatite (BAp) c-axis, an important bone quality parameter based on the microstructural anisotropy in intact, pathological, and regenerated bones. The preferential degree of the BAp c-axis strongly depends on the bone position, in vivo stress distribution, bone growth, degree of pathology and regeneration, activity of bone cells, gene defect, etc. We attempted to challenge clarification of the BAp preferential alignment formation mechanism and control the degree of BAp orientation by using an anisotropic biomaterial design to develop suitable distribution of the BAp c-axis orientation.
Properties of Polyethylene Foam Incorporated with Extracted Lignin from Pulping Black Liquor
Authors: Boonprasertpoh Aekartit , Pentrakoon Duanghathai , Chavasiri Warintorn
Published: June 2010

This research was a study of physical and mechanical properties of polyethylene foam incorporated with various amount of lignin from 5 to 20 phr.The lignin was isolated from black liquor from Kraft pulping using a sulfuric acid at pH 3 and washed with hot water. A Fourier Transform Infrared Spectroscopy (FTIR), Thermo Gravimetric Analyzer (TGA), and Laser Light Scattering were used to characterize the extracted lignin.The preparation of polyethylene foam was carried out using two-roll mill and compression moulding.Visual inspection, density measurement, and Scanning Electron Microscope (SEM) were used to investigate physical properties while compression test and compression set were used to investigate mechanical properties.The average lignin particle size diameter appears to be 31.733 m. The foam density increased slightly with amount of lignin.From SEM micrographs, it exhibited that all PE foams had a closed-cell structure where the cell sizes varied with amount of lignin.Foam incorporated with 10 phr of extracted lignin showed the finest cell distribution with an average cell diameter of 0.51 millimeters.
Grain Boundary-Dependent Selection Criteria for Nucleation of Gamma-Massive Grains in TiAl-Based Alloys
Authors: Sankaran A. , Bouzy Emmanuel , Barnett Matthew R. , Hazotte Alain
Published: June 2010

Rapid cooling of TiAl-based alloy from α phase (disordered hexagonal, A3) generates  phase (ordered tetragonal, L1o) grains through massive transformation nucleating mostly over the α/α grain boundaries. This current work deals with the identification and the validation of different nucleation mechanisms during  massive transformation in TiAl-based alloys. Special attention has been given to the variant selection criteria for the nucleation of the massive structures along different types of α/α grain boundaries. The  massive domains formed along the grain boundaries were analysed using high resolution electron backscattered diffraction (EBSD). Statistical studies were made on different nucleation sites and different mechanisms are proposed. Two–dimensional studies of the nucleation mechanism suggest that the minimization of the interfacial energy could be the predominant criteria during the grain boundary nucleation. In order to verify this nucleation criterion in three-dimensions, serial sections were made and EBSD maps were taken and analysed in each section. The variant selection observed during the nucleation and the growth of the  massive grains is further discussed after getting a broader view under three-dimensional investigations.