bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement of Carrier Concentration of Si by One Pair of Hot and Cold Needles
Authors: Zhao Yu , Zhu Yan Yan
Published: December 2011

In semiconductor industry, carrier concentration of a semiconductor material needs to be measured. Theoretical computation is complex and has its limitation. Experiment measurement always needs complicated and expensive instruments. Here, a new method for measuring the carrier concentration of Si was put forward. The dependence of thermoelectromotive force on temperature was graphed. The results showed that when temperature is below 460K, thermoelectromotive force is proportional to temperature of the hot probe. Compared with other similar methods, this method is more simplified and thet equipment is cheaper.
Optimization for Powertrain Mounting System Based on Theory of Energy Decoupling
Authors: Sun Yong Hou , Jin Guo Cai
Published: December 2011

Comfortableness of cars is influenced obviously by engine vibration. Aiming at the vibration problem of passenger cars, this paper presents an optimal method for powertrain mounting system which bases on energy decoupling method. Firstly, a six-freedom dynamic model of powertrain mounting system of passenger cars is established. Then, an optimal process of mounting system is conducted by using the theory of energy decoupling with maximizing decoupling rate of the six-freedom mounting system as objective. The theory of energy decoupling and the elastic theory are applied to optimize the design of powertrain mounting system in Matlab software. Powertrain mounting system is implemented by ADAMS software. At last, optimal results of Matlab and ADAMS are compared. The comparison results illustrate effectiveness and rationality.
Pile Foundation CAD Software System
Authors: Li Jia Wen , Chen Xu , Li Bang De
Published: December 2011

Pile foundation is commonly used in modern structure of deep foundation forms. It is characteristic of good bearing capacity and lower settlement, making convenient and suitable conditions widely, etc. The pile foundation of the design calculation process is complexity. And it is time-consuming difficult manual calculation. It is not achieved satisfactory effect. Because of this, it is imperative to using computer to engineering design. Based on the analysis of the pile foundation of the space and the matrix displacement method, it is taking object-oriented programming method and Visual C++6.0 as system developing platform, parameterized drawing method. It realized the pile foundation of automatic design, analysis, calculation and drawing process. And it is achieving all the functional in the same operation platform system that it can finish from the data input to the graphics output. It greatly improves the system automation level, and improves the pile foundation design work efficiency.
Finite Element Analysis of a Brass Cartridge Case
Authors: Peng Yun
Published: December 2011

The cartridge endures the load of very high pressure and heat generated from the fired-gas of powder when shooting. The intensity of the cartridge influences the performance of the weapon as well as the safety of user. One brass cartridge snaped in the test. Based on the theory of elastic-plastic mechanics, thermal-stress and contact mechanics, the high fidelity finite element model of the cartridge case and the gun wall is built, which is used to analyze the stress-strain field in the platform of the general FEA software ANSYS. The model is two-dimensional for the axial symmetrical characteristic, and we achieve the parameter model using the ANSYS Parameter Design Language. The resultant position of maximal stress is consistent with the test, and it oversteps the material yield limit, showing the model is high fidelity. The influence of initial gap is researched in detail, and the results indicate that the position of the maximal stress can be adjusted by controlling the initial gap. The data can be used in the modified design.
Research on Thermocouple Embedded Position for CC Mould Copper Plate with Different Cooing Water Temperature
Authors: Sun Li Gen , Li Hui Rong , Zhang Jia Quan
Published: December 2011

Cooling water temperature is one of the key parameters for continuous casting, and it has great influence to the thermal state of the mould copper plate. The coupled visco-elasto-plastic FEM models have been presented for thermal process analysis of steel the mould copper plates. With the understanding to the mould thermal state for different heat transfer coefficient, the characters of mould copper plate thermal state is obtained. It is shown that, when the cooling water temperature increasing, the surface temperature of the mould plate would be higher, but the temperature distribution trend is steady, and at same time, the cooling water temperature has little influence to the equivalent strain distribution, especially for the nodes nearer to the meniscus. Lower cooling water temperature would cause bigger mould copper plate equivalent strain, and induce more surface crack of the strand. For breakout signal catching of this mould, the thermocouple is better to embedded lower than 350mm to the meniscus by vertical, and less than 30mm to the mould cold side by level.
Studies on Modular Design of Milling Planer that Facing Variant Design
Authors: Liu Fu Yun , Yang Yun Ze , Deng Yan Rong , Xu Kun , Sun Ying
Published: December 2011

Variant design has already become the focus of digital design, and modular design is the foundation for realizing variant design. To realize variant design for a certain class of milling planer, according to the analysis of the characteristics and developing situation of milling planer, a modular design method orienting to variant design is presented in this paper. Functional independence of module should be the first priority in the method; then the structural independence. By using the method of system analysis, combining with parameters and type spectrum of series of products, module division is successfully implemented on milling planer. The feasibility of this method is verified by experiments. The ability to respond to the market of this product has been improved significantly.
Study on Optimization of Engine Accessory Bracket Based on Optistruct
Authors: Wang Yuan , Zhu Hui Tian , Xu Li , Ji Jian Ping , Dai Xi Liang
Published: December 2011

Optimization of an engine accessory bracket is conducted by using the method offered by the Optistruct software. An initial structure is created based on the interspaces left by the layout of accessories，and multiple static and modal analyses are carried out in order to obtain basic stiffness and modal information. Then a model which minimizes the structural weight with the displacement and frequency constraints for multiple loading cases is defined. The simulation yields an optimal topology. According to the optimal topology and considering some other factors, a new design is created and FEA is made to validate the design. The results show that the method can accessory bracket light in weight and maximum is stiffness.
Mechanical Bending Simulation of Thin Stainless Steel by Using Isotropic and Orthotropic Properties
Authors: Siwadamrongpong Somsak , Kitkamthorn Usanee , Sajjawattana Chaiyapak
Published: December 2011

The most important factors in hard disk drive suspension manufacturing is the suspension preload, so call “gram load”. The suspensions were generally made from cold rolled stainless steel (SUS304). The suspensions were formed by mechanical forming and gram load was adjusted by mechanical bending until reached a specification. The material properties in mechanical bending simulation of thin stainless steel were usually as isotropic for simple calculation. But the properties of thin stainless steel should be defined as orthotropic materials. Therefore, this work aimed to study gram load results of using isotropic and orthotropic properties. The thin stainless sheet was cut and test for mechanical properties in rolling and transverse directions. The properties of the thin sheet were applied to simulation model. It was found that orthotropic material properties shows a good agreement with the experimental results more than using isotropic material properties. Therefore, the results of this work could be used to explain and predict the mechanical response on the suspension manufacturing.
A Comparison of Cover Coat Methods for Electronic Flexible Printed Circuit (E-FPC) Based on Peeling Strength
Authors: Tantrairatn Suradet , Pitayachaval Paphakorn , Rangklang Sirisak , Srisertpol Jiraphon
Published: December 2011

In electronic flexible printed circuit (E-FPC) manufacturing procedure, the cover laminating process in which the line circuit (copper wire) is covered with hot cover layer on the printed circuits is importance process. This process will help to increase elasticity, strength and corrosion protection to the product therefore this process can affect directly to quality of the printed circuit. The process for laminating printed circuits can be classified into two methods by coating with industry iron and hot bar machine. This article compares the quality of the electrical circuit between industry iron and hot bar machine methods in the cover coating process by using Peeling Strength to indicate the quality in the same temperature and time condition. The experimental result illustrates the electrical circuits using the hot bar machine method give Peeling Strength value in the acceptable range and the laminating surface of circuits is smooth and uniform. On the other hand, Peel Strength value of electrical circuits using the industry iron method is unsteady and lower than the acceptable range. Moreover the result circuit product has wrinkled coating surface and become the waste product.
Optional Design Research of a Composite Wing Based on Sensitivity Analysis
Authors: Yi Long , Hong Hou Quan , Li Yu Liang
Published: December 2011

The popular finite element packages can quite well provide the structural behaviors for a given model, but the optimal design technology based on FEM is not so mature for large structures for lacking perfect sensitivity analysis. The optional design of a composite wing is accomplished by implanting semi-analytical sensitivity analysis technology into ANSYS. The structure total mass is reduced about 24%. The optimum solution not only satisfies all the restrictions, but also exhibits more uniform strain distribution. The workload of coding is reduced distinctly by this method, and the research is focused on the more important aspect of sensitivity analysis, which is useful in the engineering problems.
Product Innovation and Evaluation Based on TOC and TRIZ
Authors: Huang Wei , Hou Liang , Zhao Na , Lin Wen Guang
Published: December 2011

Abstract. According to the problems that how to excavate the essential issue behind phenomenon and how to design innovatively aiming at a certain problem, a process of product innovation and evaluation integrated by the theory of constraint and TRIZ innovation method was proposed. The process contains three parts. Firstly, through analysis of product functions, its current reality tree (CRT) and contradiction resolution diagram (CRD) was established to excavate the underlying causes of undesirable effects (UDEs). Secondly, one or more innovative solutions can be got by using TRIZ tools to solve the conflicts generated from the analysis of CRT and CRD. Thirdly, the evaluation model based on triangle fuzzy numbers hierarchical analysis was constructed to evaluate those innovative solutions and choose an optimal solution. Finally, an example was also given to show the effectiveness of the process.
Tool Wear in Sheet Metal Stamping
Authors: Yan Wen Yi , Pereira Michael P. , Rolfe Bernard F.
Published: December 2011

This paper discusses our recent research on wear at the die radius in sheet metal stamping. According to wear theory, contact pressure and sliding distance are the two dominant factors in determining sliding wear. We applied the finite element analysis to accurately quantify the contact pressure and sliding distance at the die radius in sheet metal stamping. The results were then applied to analyze sliding wear at the die radius. We found that a typical two-peak steady-state contact pressure response exists during a channel forming process. The steady-state contact pressure response was preceded by an initial transient response, which produced extremely large and localized contact pressures. We proposed a method to numerically quantify the sliding distance, which was applied to examine the contact sliding distance at the die radius. Correlating the contact pressure and sliding distance, a new insight into the wear/galling that occurs at the die radius in sheet metal stamping was gained. The results show that the region close to zero degrees on the die radius is likely to experience the most wear, with the identified transient stage contributing to a large proportion of the total wear.
Mechanism and Tendency of Die Erosion in Al-Si Casting Alloy for Permanent Mold Casting Process
Authors: Kim Bong Hwan , Lee Sang Mok
Published: December 2011

The mechanism of die erosion in Al-Si alloys was investigated based on the formation behavior of iron-containing intermetallics. And the metallurgical parameters affecting on the erosion tendency were discussed as functions of chemical composition for a guideline of melt control in Al-Si foundry. It was found that the intermetallic layers of α-AlFeSi, β-AlFeSi and θ-AlFe were formed through metallurgical reactions. The erosion tendency of die material was determined by not only the gradient of iron content through the interface between die material and molten alloy but also the relative formation temperature of primary intermetallics.
Fault Diagnosis of Bearing Based on the Ultrasonic Signal
Authors: Su Lian Cheng , Shi Yan E , Li Xiao Li , Zhang Yan Liao , Zhang Yang Ping
Published: December 2011

The bearing of rotating machinery often fails due to the frictional forces of rolling element, in the early stages of the faults, a series of ultrasound can be generated in short time intervals, which occur at bearing characteristic frequencies. Since the frequencies of ultrasonic signal are very high, they will lead to much higher computing burden when using the common technique of Fast Fourier Transforms (FFT) directly. In this paper, envelope detection technology and heterodyne technology which integrated in an ultrasonic data collection system are used to reduce the frequency effectively. To allow for the easier detection of the bearing faults, these two techniques has been used together with FFT. A verification research with respect to vibration analysis is carried out to analyze the effectiveness and superiority of ultrasonic data collection in time domain and frequency domain aspects respectively. Extensive experiments have been performed in an Alternating Current (AC) motor system, and the results indicated that this ultrasonic data collection system is as useful as vibration analysis system in diagnosing the faults of bearings. In addition, it is more sensitive in fault diagnosis in the early stages of the bearing faults than vibration acquisition system.
3D Measurement Method Based on Binocular Vision and Linear Structured Light
Authors: Qu Xue Jun , Song Yue Wen , Wang Yong
Published: December 2011

To improve efficiency of industry inspection, measuring method of part shape which combines laser linear scanning and binocular vision is researched. In the system, two cameras are located at certain angle, and linear structured light is projected onto the part surface to produce distorted laser light stripe, which is used as measure feature curve. Ordinary planar plate is used as the calibration template in system calibration and images of serial parallel lines bundle are displayed on it which are acquired simultaneously by the camera to produce image series. Calibration parameters are divided into several parts, so as to calibration of them so that interference between different parts can be eliminated significantly. Based on above works, system calibration and reconstruction of 3D coordinate are implemented successfully. Experimental result shows our method’s feasibility and effectiveness, thus good prospect can be expected to it.
Nozzle Flow Model of High Pressure Variable-Rate Spraying Based on PWM Technology
Authors: Zhai Chang Yuan , Wang Xiu , Liu Da Yin , Ma Wei , Mao Yi Jin
Published: December 2011

Nozzle flow model for high pressure variable-rate spraying is indispensable when orchard sprayer is controlling liquid flow based on Pulse Width Modulation (PWM) technology. Three flow models for Teejet AITXA 8002, 8003 and 8004 nozzles are obtained by using nozzle flow model test system which is established in this paper. The results from equation hypothesis test and test for lack of fit of flow model shows that those three flow models work well. Nozzle flow model validation trials show that the relative errors of model flow and actual flow are small, while the maximum relative error is 6.50%; the flows characteristics of different nozzles with the same type are almost the same.
Design, Modeling and Simulation of an Innovation Pneumatic High Speed on-Off Valve Based on Giant Magnetostrictive Material
Authors: Zhang Feng , Liu Hao , Tao Guo Liang , Zhong Wei
Published: December 2011

Based on giant magnetostrictive material, a new design of pneumatic high speed on-off valve is presented in this paper. To settle the problem of balancing fast response and large flow, a cantilever beam is employed as both displacement amplifier and valve spool in the innovation structure of the valve. The dynamic model of the valve is established by analyzing the dynamic performances of the giant magnetostrictive actuator and the cantilever beam, based on the theories of electromagnetism and the mechanical vibration. A simulation on this model is carried out to investigate the performance of the valve. Results of the simulation show that the new pneumatic high speed on-off valve is able to achieve the goal of high frequency response, while satisfying the requirement of a large flow.
A Path-Planning Algorithm for AGV Based on the Combination between Ant Colony Algorithm and Immune Regulation
Authors: Huang Jian Zhong , Cen Yu Wan
Published: December 2011

For the demand of AGV’s environment modeling and path-planning,the paper discusses how to establish static environment model of visibility graph and proposes a visibility table method.Moreover,based on the environment modeling,we put forward a new kind of global path-planning algorithm by the combination between ant colony algorithm and immune regulation.
The Rapid Modeling and Application of Optimization in Management and Organization for Mini Harbour
Authors: Li Fa Ming , Zheng You Xin
Published: December 2011

In order to optimize the managing mechanism and setup organization, With the help of the concept of software component and component software, enterprise model components and component-based enterprise models were presented in this paper. In this way, Acomponent-based port model can be created rapidly and efficiently, the celerity managing component model of library is establish .
The De-Noising Algorithm Based on Intrinsic Time-Scale Decomposition
Authors: Zeng Jin Xia , Wang Guo Fu , Zhang Fa Quan , Ye Jin Cai
Published: December 2011

A new de-noising algorithm based on Intrinsic Time-scale Decomposition (ITD) is proposed after analyzing the statistical characteristics of additional Gaussian white noise decomposed by ITD. Compared with the Wavelet Threshold De-noising(WTD) and de-noising algorithms based on empirical mode decomposition (EMD), the numerical simulation results show that this algorithm has comparable performance with the de-noising based on EMD and the WTD, and it is no need for spline interpolation, iterative sifting and selection of the wavelet base. It is a new adaptive de-noising algorithm.
Improve on the Ticket Vending Machine for the Railway
Authors: Min Xu Guang , Li Guang Zhen , Wan Tao
Published: December 2011

The automatic ticket vending machine that referred to in this paper is innovative, either from the structure, function or principle, it is fundamentally different from the tradition vending machine. It is a combination of reading card technology in industry and business, especially designed a special answer-sheet. Each card costs RMB 0.1 Yuan or less. Passengers use the purchasing ticket card in the automatic ticket vending machine, which is the rapid and intelligent process of obtaining the ticket, and greatly reducing the time in the tradition automatic ticket vending machine.
The Temperature Field Finite Element Analysis and Simulation of One Kind of Magnetic Agitation System
Authors: Liu Zhi Hua , Li Jian Peng , Guan Weh Hao , Yang Shuo
Published: December 2011

A magnetic beads agitation device is given based on electromagnetic MEMS. The micro planar coil which is used for controlling the magnetic beads in the device will generate heat, and the heat will directly affect the reaction droplet’s temperature, even lead the failure of the reactants and enzymes. Against this problem, the mathematical model for temperature field analysis of magnetic beads agitation device is established based on three-dimensional transient heat balance equation, boundary conditions of radiation and convection; and then the finite element model for the magnetic beads agitation device is established; in the end, simulation and calculation of temperature field distribution of the device are done in different load, and the simulation results are coincident with the existing literature’s experimental results ,which verified the correctness of this analysis method.
Microfludic and Heat Transfer Performance of Multilayer Fractal-Like Microchannel Network
Authors: Fang Kuang , Xu Shang Long
Published: December 2011

Due to the limitation of dimension, the cooling of microelectronic devices with high heat flux may be sometimes beyond the reach of heat sink which is fabricated with single layer structure, no matter which kind of mircochannel you choose. Various innovative methods have been investigated to tackle this problem. Among them, microchannel heat sink with multilayer structure is possibly one of the most effective cooling techniques. In this paper, the conjugate fluid flow and heat transfer characteristics of multilayer fractal-like microchannel network embedded in a disk-shape heat sink are investigated using a CFD approach. The intrinsic advantages of multilayer fractal-like microchannel network compared with single layer one are demonstrated, such as low total pressure drop, low maximum temperature, and temperature uniformity.
Study on Sustainability and Ecological Trend Design of Green Hotel Building
Authors: Xu Qiang
Published: December 2011

The problem what the sustainable design of the hotel concern is how to maximize meet the requirements of the management by the means of planning and architectural design for decades to come and how to cut down the cost of operation and maintenance. On the basis of the design idea of the ecological energy saving, key space comfort in modern hotel architecture, the key element of ecological design of green hotel is discussed. Based on the planning design of a star-rated hotel in Changchun, the strategy of sustainable development, such as site selection, water resources, natural climate environment, utilization of renewable energy, indoor environmental quality, green building materials are analyzed.
The Working Mechanism Innovation of College Counselors Based on Modern Tool
Authors: Yu Rong
Published: December 2011

The high speed developmental computer net and mobile phone brings accident and challenge to the college academician antilogy politics education work. The college counselor agendum mechanism was innovation talked from the development corner of the modern net implement aiming at the now college counselor work characteristic. The work approach and instrument which relying on the modern implement of the counselors was summarized. The practice proved that these methods were effective and being provided with biggish extended value.
Comments on NOx Emission Abatement in Cement Industry
Authors: Liu Rui Cui , Jiang Fu Yi , Liu Zi Quan
Published: December 2011

Abstract:The article first described all kinds of pollution produced in the cement production line, mainly include air pollution, dust pollution, noise pollution and so on。Then the author stressed the physical and chemical characteristics of the produce of NOX in waste gas and the prevention and emissions reduction. Furthermore, the paper made a analysis of NOX emissions standards and pollution in current domestic and foreign cement plant, and give a few NOX removal and recovery technology at home and abroad. Among them，the article expounded the principles, process and application status of the reduction of ammonia nitrogen removal, and give it a simple evaluation.
Dynamics Investigation on Bidirectional Active Flexible Bending Joints
Authors: Liu Xiao Min , Wang Yi Qiang , Geng De Xu , Zhao Yun Wei , Zhang Jin Tao
Published: December 2011

To aim at the characteristics of combination of pneumatic elastomer of flexible joints, the uniform distributed mass of pneumatic artificial muscle (PAM) was equivalent to the concentrated mass of the two ends by means of equivalent mass method; then the kinematics differential equation of the PAM was set up; and the natural frequency of PAM was consequently obtained. Based upon the above analysis, the dynamic model of joint with variable parameters was then analyzed; both the axial and bending dynamic performance of the two directional active bending flexible joint was studied and their natural frequency separation was obtained. And this study provides basis for making humanoid robot hand using this flexible joints.
Preparation and Characterization of V-Type Amylose-Hexanol Complex
Authors: Yang Liu Zhi , Xiao Xin Xin , Zheng Miao Miao , Xu Yin Long , Liu Yan Qi
Published: December 2011

In this paper, B-type microcrystalline starch made a combination with hexanol in the case of water and alcohol as solvent respectively, V-type amylose-hexanol complexes were prepared. Obtained V-type amylose-hexanol complexes were characterized with scanning electron microscopy, X-ray diffraction, differential scanning calorimete. The results showed that using the preparation of water and alcohol solvents, obtained V-type amylose-hexanol complexes were hydrates and anhydrous crystal respectively. Hydrate crystal’s particles adhesion were serious, the particle diameter of anhydrous crystalline was 0.5~1μm, the crystallinity of both were above 70%. The V-type complexes prepared by aqueous solvent method and alcohol solvent method had almost the same melting temperature, the melting temperature of hydrates and anhydrous forms crystal were 70.7°C and 69.36°C.
Formation Mechanism and Characteristics of the Bei’an to Heihe Expressway K177 Landslide
Authors: Shan Wei , Jiang Hua , Cui Gao Hang
Published: December 2011

Bei'an to Heihe highway is being widen to expressway at present in Heilongjiang province, some sections are located in ancient landslide bodies, influenced by the landform, rainfall, freeze thawing and anthropogenic factors, are in unstable states, bring great difficulties to construction. Took the Bei'an to Heihe expressway expansion project K177 landslide as the research object, employed the field investigation, geological drilling, field monitoring, indoor experiment and numerical simulation methods to carry an integrated study on the formation mechanism of the landslide. The research results show that: topographical, geological conditions and the water content change of slope rock and soil is the main reason causing landslide; atmospheric precipitation, seasonal freezing and thawing of the shallow soil and the island permafrost which scattered in the mountain valley melting provide a continued water source for landslide, thermal contraction cracks of slope surface and high permeability of surface rock and soil provide passage for water infiltrating, completely weathered mudstone above the aquifuge which is influenced by infiltration water to be soften forms rupture surface.
Numerical Simulation of Temperature and Flow Field on Single Channel Drum Dryer
Authors: Wang Xue Ping , Luo Shu Qi , Zhang Liang , Zhang Zhen Wei
Published: December 2011

This paper primarily focuses on the analysis on the mixed-phase aiming at obtaining the temperature distribution, the regular of velocity and pressure changes of the dryer. The authors took advantage of the software of the Fluent to establish the model and then simulate the mixed-phase model. Through the analysis, the parameters of the dryer can be figured out. The paper also analyses trajectory of particle in the dryer according to the simulation of the discrete phase. The conclusion of this paper provides the basis for the better understanding the drying mechanism and optimization of the structure design.
Root Characteristics and Yield of Greenhouse-Grown Cucumber in Continuously Cropped Soil
Authors: Liang Yin Li , Lin Xing Jun
Published: December 2011

The cucumber (Cucumis sativus L.) production in greenhouse-grown reacted an important on vegetable supply. An experiment was conducted, during the 2001-2002 and 2002-2003 cropping seasons, November 2001 to the early July 2002 in the first season, and October 2002 to early July 2003 in the second season, in a solar greenhouse on the Loess Plateau in Yan’an, Shaanxi, Northwest China, to study the root characteristics, growth and fruit yield of cucumber as affected by growing in soils that have been continuously cropped cucumbers for 0, 1, 4, and 8 years. The results showed that the number of cucumber roots, root length, root dry weight, plant height, and leaf number decreased, but root diameter increased as the duration of continuous cropping increased. The fresh fruit productivity was the highest on the soil with 1year cropping history and decreased as the duration of continuous cropping increased to 4 years or more. Root number, root length, and root weight were correlated positively with yield whereas root diameter was correlated negatively with yield. The results emphasized the point that 4 years duration of continuous cropping is an important warning time for greenhouse cucumber production. If the duration of continuous cropping was beyond 4 years, poor root growth and decrease in yield of the cucumber would start appearing. In order to promote root development and increase fruit productivity, beyond 4 years of continuous cropping should be avoided in cucumber production management.
External Load Variability of Multibucket Machines for Mechanization
Authors: Bošnjak Srđan , Zrnić Nenad Đ. , Gašić Vlada M. , Petković Zoran D. , Simonović Aleksandar
Published: December 2011

This paper discusses the problems of identifying external loads of multibucket machines for mechanization. External loads are dominantly dynamic with distinguished stochasticity in certain cases. The paper presents the procedures for determining external loads caused by resistance-to-excavation (for bucket wheel excavators) or grabbing soil (for bridge-type coal stacker-reclaimers), as well as a short description of the model upon which is based and defined the response of the stacker-reclaimer to the external changeable load. It points to the significance of the problem of identifying the external load, as well as to the potentially very detrimental and dangerous consequences of eventual shortcomings during solving the mentioned problem.
Study on Fatigue Characteristic of Double Block Ballastless Track under Coupling Loads
Authors: Zeng Zhi Ping , Wang Xue Song , Chen Wen Rong
Published: December 2011

Regarding double block ballastless track as research subject, three mechanical models were established, which include steel bar and concrete interaction mechanical model, spatial finite element static model of double block ballastless track, train-double block ballastless track vertical coupling dynamics model. According to concrete and steel bar stress time-dependant curves under axial even temperature and shrinkage load, temperature grads load and train load, fatigue load spectrum under coupling loads was obtained by using rain-flow counting method. Based on steel bar and concrete S-N curve, and Palmgren-Miner linear fatigue damage accumulation rule, track concrete layer fatigue life predicting model of double block ballastless track was established. Taking Changsha climatic condition for an example, the fatigue life of double block ballastless track is predicted, and the effects of design parameters to fatigue life are analyzed.
Sliding Mode Control for a Class of Unmatched Uncertain Linear System
Authors: Zhao Zhan Shan , Sun Lian Kun , Zhang Jing
Published: December 2011

A novel method of designing nonlinear robust sliding mode controller is presented to a class of nonlinear unmatched uncertain systems based on integral sliding mode and self-tuning law. Firstly, the unmatched is will not be amplified by the discontinuous control. Then the controller based on integral sliding mode is constructed to ensure the robustness. The stability of proposed procedure is proven by using the Lyapunov theory and guarantees robustness against uncertainties. The upper bounds of uncertainties are not required to be known in advance. Finally, simulation studies demonstrate that the proposed controller is robust with respect to the perturbation.
Numerical Analysis of Influencing Factors of Uneven Settlement in Abutment Foundation
Authors: He Qiang , Wang Dian Ju , Peng Nian
Published: December 2011

The uneven settlement of ground is the common problem in the engineering construction. Based on the Fuyan Bridge whose uneven settlement of ground leads to the crack of abutment and arch ring, the settlement deformation of abutment ground is analyzed by means of FE software ANSYS with the hypothesis of soil parameters. The law and curves are obtained that illustrate the relationship between variation of calculation parameters in soil & settlement deformation in abutment foundation, which offer references to design and construction of other similar projects.
An Environmental Factors-Based Automatic Control System for Folding Arm Awning
Authors: Zhu Qing Yuan , Wen Cheng Lu , Xie Wen Yi , Du Xiao Hui
Published: December 2011

This paper developed an automatic control system for folding arm awning based on environmental factors, which can overcome the disadvantages of the traditional awning of unitary control mode and low level of intelligence. The system consists of sensor unit, controller, drive motor and transmission mechanism. The sensor unit is used for testing light intensity, wind speed and rain, then an AT89S52 SCM single-chip microcomputer which is the core of the controller is applied to receive testing signal and send instructions to AC motor to realize the extending and withdrawing state of the awning according to the corresponding control logic. Meanwhile, this system is able to switch from automatic control to manual control so as to deal with power outage and other special situation and maintain operation of awning. The results of the prototype test show that this system is running steadily and can adjust the working condition of the awning in time according to the environment change. Compared with the current electric awning, the intelligent folding arm awning controlled according to environmental factors can achieve more energy conservation and environmental protection.
A Stochastic Optimization for the Optimal Texture of Ferroelectrics for Piezoelectric Applications
Authors: Jayachandran K.P. , Guedes J.M. , Rodrigues H.C.
Published: December 2011

A stochastic optimization procedure incorporating a continuum modelling is used to identify the optimal texture (orientation distribution) parameters of ferroelectrics (FEs) for piezoelectric applications. FE polycrystals differ significantly from single crystals because of the presence of variously oriented crystallites. The orientation of FE crystals plays a critical role in the anisotropy of their piezoelectric properties. The set of combination of variables, known as solution space, which dictates the texture of crystallites is unlimited. Crystallographic orientation in FEs is characterised through Euler angles . The macroscopic properties of a ceramic FE, differ significantly from those of single crystals mainly due to the imperfect alignment of the crystallographic axes of the constituent domains or crystallites. This suggests that piezoelectric properties can be tailored by a proper choice of the parameters which control the orientation distribution. Nevertheless, this choice is complicated and it is impossible to analyze all possible combinations of the distribution parameters or the angles themselves. Stochastic optimization combined with a generalized Monte Carlo scheme optimizes the objective functions, the effective piezoelectric coefficients . Objective functions are calculated using the homogenization method at each orientation configuration chosen by the optimization algorithm. A modified simulated annealing is employed to describe the stochastic optimization. Here we have simulated the texture of polycrystals using a simple model with a Gaussian distribution. Optimal design variables that enhance the macroscopic piezoelectricity are identified.
Textured Multiferroics: 2-D Diffraction and Properties Prediction
Authors: Muñoz-Romero Alejandro , Fuentes-Montero L. , Montero-Cabrera M.E. , Trivedi U. , Fuentes-Cobas Luis E.
Published: December 2011

A description of recent work performed by collaboration among the CIMAV Crystal Physics Group, the ILL Diffraction Group and the GEC Nanotechnology Education and Research Centre (NERC), regarding structure-electromagnetic properties relationships, is given. Structure analysis puts emphasis on thin films texture characterization. The new software package ANAELU, for texture analysis via two-dimensional (2-D) diffraction detection, is described. Crystallographic texture plays a significant role on ferroic and multiferroic bulk and nano-structured materials properties. With the objective of estimating effective values for polycrystal dielectric, piezoelectric, elastic and magnetoelectric coefficients, the Voigt, Reuss and Hill approximations are systematized in an extended version of program SAMZ.
On the Bumps and Curves in the Microband Boundaries in a Channel-Die Compressed Goss-Oriented Ni Single Crystal
Authors: Zinnia Nasima Afrin , Quadir M. Zakaria , Bassman Lori , Driver Julian H. , Albou A. , Ferry Michael
Published: December 2011

The crystallographic alignment of microbands in a Goss oriented single crystal was investigated by two and three dimensional electron back scatter diffraction. The microband boundaries were found to be curved instead of being perfectly flat interfaces, and the overall alignment closely matched a potential slip plane. The bumps and curved were created during subsequent deformation and, thus, deviates the microband boundaries from crystallographic nature.
Deformation Induced Percolating Porosity In High Pressure Torsioned (HPT) Copper
Authors: Wegner Matthias , Leuthold Jörn , Divinski Sergiy V. , Setman Daria , Zehetbauer Michael J. , Wilde Gerhard
Published: December 2011

Copper of different purity levels (4N, 5N) produced by High Pressure Torsion (HPT) with varying processing parameters is investigated utilizing the radiotracer technique. While the degree of deformation is constant, the effect of the applied quasi-hydrostatic pressure and of the impurity concentration on the as deformed samples is analysed. By applying the radio tracer method micro structural aspects are revealed that are not easily accessible by conventional methods. The measurements indicate the formation of a percolating porosity during the HPT process as a function of the applied pressure and (although less pronounced) of the impurity concentration.
Metallographic Studies on Deformation Microstructures of ECAE Processed AA 2014 Aluminium Alloy
Authors: Murugesan A. P. , Giribaskar Sivaswamy , Gouthama
Published: December 2011

Different initial texture of ring rolled AA 2014 alloy was processed to one pass in Equal Channel Angular Extrusion (ECAE) at room temperature. The material flow/deformation characteristics as well as the degree of grain refinement, as a function of different initial grain morphological orientation are studied. Macroscopic and microscopic investigation by Optical Microscope (OM) confirms the significant variation in the shearing characteristics of grains in the billets in each orientations. OM observations also suggested that the severity of deformation was more in middle portions of the extruded billets. TEM observations made on the samples also confirmed the existence of regions which had undergone the different degree of dynamic recovery and recrystallisation after passing through shear deformation zone.
The Role of Processing Routes on the Evolution of Microstructure and Texture Heterogeneity during ECAP of Al-Cu Alloy
Authors: Venkatachalam Perumal , Roy Shibayan , Paul V. Thomas , Vijayalakshmi M. , Ravisankar Balasubramanian , Suwas Satyam
Published: December 2011

The effect of processing routes during Equal Channel Angular Pressing (ECAP) of the Al alloy 2014 with regard to the evolution of microstructure and texture heterogeneity has been studied. The solution treated alloy (768 K for 1 hr) was subjected to ECAP through routes A, BA, BC and C using a die with inter-channel angle 90° upto 5 passes. Texture evolution was studied in the top, middle and bottom of the billets processed through routes A, BA, BC and C. Processing by route A resulted in a stronger texture evolution because of monotonic increase in strain with the number of passes. In route A, texture heterogeneity is more than the routes BC and BA. In routes BC and BA, the texture evolution in outer region near to surface of the billet changes their orientation as the passes increases possibly creating a stronger texture evolution at the top and bottom different from the centre of billet. The heterogeneity in texture evolution is the least less in route C, due to the reversal of shear.
Texture Evolution of IF-Steel Sheets Processed by Equal-Channel Angular Sheet Extrusion (ECASE)
Authors: Saray Onur , Pürçek Gençağa , Mahato B. , Chowdhury Sandip Ghosh
Published: December 2011

Interstitial-Free steel (IF-steel) sheets were severe plastically deformed using a continuous equal-channel angular extrusion/pressing technique called “Equal-Channel Angular Sheet Extrusion (ECASE). After processing, texture development as well as microstructural alteration and tensile properties were investigated. The microstructural investigations revealed that the processed sheets exhibited a dislocation cell and/or subgrain structures with mostly low angle grain boundaries. It was also observed that the strength of the processed sheets increased substantially after ECASE processing in the expense of ductility. It was shown that the ECASE has moderate influence on the texture of IF-steel sheets through route A. Intially there was θ partial fiber which changes to {110}θ with straining.
Grain Refinement Mechanisms Oterative during Equal Channel Angular Pressing of Aluminium
Authors: Manna Rampada , Mukhopadhyay N.K. , Sastry G.V.S.
Published: December 2011

Grain refinement of aluminum deformed by equal channel angular pressing is strongly dependent on the amount of strain. The refinement process at low to high strain level involves elongation of the existing grains by shear deformation, their subdivision into bands and subgrain formation within bands, intersection of the bands during subsequent passes and finally conversion of the subgrains to grains by continuous dynamic recrystallization process. At room temperature the conversion of subgrains to grains takes place by progressive lattice rotation.
Interactive Effects of Strain, Strain-Rate and Temperatures on Microstructure Evolution in High Rate Severe Plastic Deformation
Authors: Shekhar Shashank , Abolghashem S. , Basu S. , Cai J. , Shankar M. Ravi
Published: December 2011

During high rate severe plastic deformation (HRSPD), strain and strain-rate are not the only external factors that determine microstructural transformations in materials, temperature-rise due to heat generation from deformation processes, also plays an important role. Temperature may influence the microstructure directly by controlling grain growth kinetics and it may also have an indirect effect through the interactive effect on material behavior, which in turn, influences strain and strain-rate parameters. This complex thermomechanics of HRSPD can lead to myriad of microstructure and consequently, material properties and phenomenon. These deformation parameters can be utilized as a ‘fingerprint’ for the resulting microstructure, and the properties and phenomenon related to it. Here, we capture some of these microstructural transformations by relating grain and sub-grain sizes, to the deformation parameters. In doing so, we find evidence of continuous dynamic recrystallization operative under these HRSPD conditions, where the interplay of strain, strain rate and temperatures offer varying degrees of multimodality in the grain-size distributions.
Microstructure Refinement During Severe Plastic Deformation (SPD) of FCC Materials: A Texture Based Study
Authors: Swaminathan Srinivasan , McNelley Terry R. , Chandrasekar Srinivasan
Published: December 2011

FCC materials were subjected to large strain deformation by three techniques: equal channel angular pressing (ECAP), plane-strain machining and friction stir processing (FSP). Based on the orientation imaging mapping (OIM) analysis of the deformed regions, the most likely microstructure refinement mechanisms have been identified for each of the techniques and compared among one another.
Investigation of Microstructure of the Commercial Pure Aluminium in the ARB Process
Authors: Dehghan Mojtaba , Qods Fathallah , Gerdooei Mahdi
Published: December 2011

The severe plastic deformation (SPD) of metallic materials has become attractive in recent years. Accumulative roll bonding (ARB) is a SPD process that can impose deformation to a sheet metal, as it develops fine grains of typically submicrometer or even the nanometer level in polycrystalline materials. The purpose of the present study is investigation of microstructural evolution and micro hardness behavior of the commercial purity Aluminium (AA1050) severely deformed by the ARB process. The microstructural evolution during 13 cycles of ARB process was investigated. With increasing ARB cycles the grains size reduced in nanometer range. Furthermore, Micro-Vickers hardness measurement was carried out throughout thickness of the ARB processed sheets.
Mechanical Anisotropy of Aluminium Laminates Produced by ARB
Authors: Chekhonin P. , Beausir B. , Scharnweber J. , Oertel C.G. , Jaschinski J. , Hausöl Tina , Höppel Heinz Werner , Brokmeier Heinz Günter , Skrotzki Werner
Published: December 2011

The plastic anisotropy was studied on aluminium sheets with layers of different purity (A: 5N and B: 2N+) produced by accumulative roll bonding (ARB). Both material layers show a contrasting recrystallization behavior where A and B are discontinuously and continuously recrystallized, respectively. Global textures were measured by neutron diffraction. The mechanical anisotropy was measured by tensile testing after different numbers of ARB cycles. The planar anisotropy decreases with the number of ARB cycles while the normal anisotropy reaches a plateau after 4 cycles. Simulations of the Lankford parameters were carried out with the help of the viscoplastic self-consistent scheme (based on the global texture) and compared with the experimental data. Deviations of the simulated values from those of experiment are discussed with regard to through-thickness texture and material heterogeneities.