bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Study on the Bombardment Effects of Tungsten by High-Intensity Pulsed Ion Beam
Authors: Wu Di
Published: October 2013

In order to study the response of tungsten under high heat load, the nonlinear thermodynamic equations considering the phase transition were established to the tungsten target irradiated by intense pulsed ion beam. Also the equations which describe the thermal stress and the total strain produced by the changed temperature in the material element were built. Numerical method was used to solve the evolutions of the thermal stress field formed in the target, and spatial temporal evolutions of stress field in the tungsten target are obtained. While the ion current density reached 100A/cm2, the surface materials of tungsten target at the beam incident center was melted and then re-solidified due to the heat conduction after the end of a pulse. There exists the gradient of temperature in tungsten, therefore the thermal stress formed. Radial tensile stress is produced within the melting region, meanwhile outside the region compressive stress is formed; the boundary appears on the edge of the melting region. The stresses on the incidental surface of target are larger compared with the internal.
Study on the Finite Element Strain Simulation Model Updating Method Based on the Real Measurement Data
Authors: Xiao Li Feng , Duan Ran , Tian Hui
Published: October 2013

When using electrometric method to measure the static strain of a structure, the results are often accurate, but the number of measuring points is limited; when using the finite element method to model and analyze the practical structures, there often exist many assumptions of uncertain factors, so the accuracy of simulation results is poor, but the strain values of all the nodes in the grid of simulation structure are available, so the number of measuring points is large. In view of this situation, this paper applied Bayes-Kriging estimation method through the measurement strain data to update the strain on the surface of finite element strain simulation model. We applied the measurement strain data at different stages of the fatigue process to update finite element model. With the comparison of the strain data between before-and after-updating, we can find that at the boundary region and fatigue crack extending direction, the updating result is inaccurate, but the updating effect is good at other position. This method can improve the accuracy of these positions' strain value and make the strain value closer to the actual strain value.
A Regulatory Network of G2/M Phase Transition for DNA Damage
Authors: Zhang L.W. , Liew K.M.
Published: October 2013

A regulatory network of G2/M phase transition influenced by different intensities of DNA damage is modeled. It contains the sub-modules of P53-Mdm2 feedback loop and G2/M phase transition process. To investigate the robustness of the regulatory network, a sensitivity analysis of kinetic parameters in the proposed mathematical model is implemented to select the most significant kinetic parameters, which are relevant to key proteins involved in G2/M phase transition. Subsequently, the statistical hypothesis testing is employed to evaluate the influence of perturbations on the G2/M regulatory network. The results indicate that G2/M regulatory network is robust to DNA damage signal when perturbations are very small that is consistent with the experimental observations.
In Instability and Failure of Steep Slope Embankment Test and Numerical Simulation Analysis of MeiHe Expressway in Guangdong Province
Authors: Zhang Zhi Yun , Fei Wei Shui , Xiang Chong , Zhou Dong Jun
Published: October 2013

In Guangdong MeiHe highway K28 + 360 ~ + 360 section of the steep slope embankment as the research object, by adopting the combination of measurement and numerical analysis methods, analyze the failure process and mode of steep slope embankment. Based on the analyses, The following conclusions were obtained: the sliding surface of fill embankments on slope foundations of K28+360~+860 section was the original surface of the slope. Constructions of the highway would block the groundwater discharge and reduce the strength of the original surface of the slope, which would cause the slide of the fill embankments on slope foundations.
Numerical Simulation of the Dynamics of Heart Valves: A Literature Review
Authors: Zhong Qi , Zeng Wen Hua , Huang Xiao Yang , Wang Bo Liang
Published: October 2013

Imaging techniques allow the visualization of the heart valves, but do not yields any information regarding the load applied to the heart valve information that provides key clues to the cause of valve deterioration. Numerical simulation, which is able to replicate and understand the dynamics of the valve, would benefit studies on heart valves surgical repair and prostheses design. Modeling and simulation of heart valves dynamics is a challenging biomechanical problem. Many researchers have taken various approaches to model the heart valve. But systematical categorization and development tendency of their research have never been discussed before. This paper reviews their models and divides them into wet models or dry models, in the light of whether considering blood flow and valve interaction. These simulations also can be categorized as native heart valve or artificial heart valve simulation by a different model prototype. The critical issues for future research are presented.
A Case Study of Application of Modern Design of Experiment Methods in High Speed Wind Tunnel Test
Authors: Li Yong Hong , Huang Yong , Wei Zhi , Feng Li Ming , Zhang Yue
Published: October 2013

For the development trend of advanced aircraft wind tunnel tests which require shorter cycle time and lower cost, a new wind tunnel testing process called Modern Design of Experiments (MDOE) is under development at NASA Langley Research Center. This paper presents a case study of application of Modern Design of Experiment methods in high speed wind tunnel tests based on the aerodynamic data of certain type of aircrafts. The full process including experiment design, execution, analysis of variance, and block design is described. Comparisons between MDOE predictions and OFAT measurements were made in the present study. The results show that the MDOE methods have well predictive capability to meet specific test objectives with less data volume, less cost and less time compared to the conventional OFAT methods, which means the MDOE approach established and used in this study is feasible enough to meet specific aerodynamic wind tunnel testing objectives in place of conventional OFAT methods.
Numerical Simulation of Supersonic Aircraft Surface Aerodynamic Heating and Infrared Radiation Characteristics
Authors: Su Pei Ran , Eri Qi Tai , Li Xi Xi
Published: October 2013

The aerodynamic heating and infrared radiation characteristics of BrahMos supersonic cruise missile were investigated. The aerodynamic heating was simulated using finite volume method, and the infrared radiation characteristics were simulated by reverse Monte Carlo method. Infrared radiation characteristics of missile surface were analyzed in different surface emissivity and flight altitudes, and the effects of environmental radiation and atmospheric attenuation were considered. The results show 8~14μm and 3~5μm environment radiation were approximately 10% and 2.4% of total radiation respectively, when the surface emissivity is 0.3. The proportion of environmental radiation reduces nearly half when the surface emissivity increases by 0.2.
Remote Sensing Integration Survey of Typical Land Types and Analysis of its Spectral Properties in Southeast of Yunnan Province
Authors: Zhang Xiao Lun , Gan Shu , Li Ying , Huang Ji Lei , Gao Shuai
Published: October 2013

Karst rocky desertification is a major ecological disaster faced by the southeastern region of Yunnan Province, in China. The research of land use status in rocky desertification area is more and more concerned by human. Through remote sensing integrated survey ways to establish the spectral database of six kinds of typical land types, such as water, forest land, paddy field, grassland, dry land and bare land; then, Normalized Difference Vegetation Index (NDVI) processing and Tasseled Cap transformation processing for the spectral data; finally, the spectral characteristics and the variation of typical land types was analyzed and studied. The results indicated that, there are no significant differences of spectral of the six kinds of typical land types, after the processing of NDVI, the water, the forest land and grassland with larger vegetation coverage, and the paddy land, dry land and bare land with smaller vegetation coverage, can be well distinguish, but the distinction between forest land and grassland is bad, the distinction of paddy land, dry land and bare land is also bad; after the Tasseled Cap transformation processing, the dispersion degree of water, forest land, paddy field and grassland is better, the dispersion degree of dry land and bare land is a bit poor, need to be further studied. The remote sensing integrated survey and the analysis of spectral properties are important foundation for the Land Use / Land Cover Change (LUCC) and the dynamic monitoring of rocky desertification in southeastern rocky desertification region of Yunnan province.
Study on Remote Sensing Image Auto-Identify Classification by Used of Object-Oriented Technology
Authors: Xia Si Wen , Gan Shu , Ren Peng Fei , Zhang Xiao Lun
Published: October 2013

In dealing with high-resolution remote sensing image auto-identify classification, the traditional pixel-based and spectral statistical characteristics classification technology or method has some insurmountable difficulties. In this paper, object-oriented image analysis method is by application, the auto-identify classification rules are set up based the different remote sensing image characteristics that included such as spectral, texture, scale and so on. As a case study, a petroleum reserve base auto-identify classification is selected as an example and the target is identified, in a better effective result by applications of the object-oriented method. The result appraising analysis indicates that object-oriented classification method to identify automatically high-resolution remote sensing images pattern object can get a high precision. The method of object-oriented has a widely potential application for remote sensing image automatic-identify classification in times to come.
Aerodynamic Shape Optimization Design of the Swept Wing Based on the Kriging Surrogate Model
Authors: Wang Dan , Bai Jun Qiang , Hua Jun , Sun Zhi Wei , Qiao Lei
Published: October 2013

The aerodynamic shape optimization design system was established in this paper. In the system, the RANS equation was used for solving the flowing; the free form deformation (FFD) method was used for the geometry parameterization, and the genetic algorithm was used for the optimization search. For the reducing of the time cost, the Kriging model was used for the surrogate model instead of the CFD simulation during the optimization design. The aerodynamic shape design of a swept wing was presented which used the system, and the result indicated that the 14% drag coefficient was reduced at the cruise conditions, which proved the validity of the system.
Dynamic Response Analysis of Suspenders of Arch Bridges Sudden Failure on Failure-Safety Theory
Authors: Li Hua , Li Rui , Chen Yue , Zhu De Xiang
Published: October 2013

Suspenders are main force-transmission components of half-through and through arch bridge, It is crucial for safety of bridges to its reliability and durability. Safety of the arch bridge will change when a suspender sudden failure, and affect the safety of the structure. Selecting a through arch bridge in Yunnan Province as the research object, it based on the three-dimensional finite element, this paper studied the dynamic response of arch bridge suspenders sudden failure on the failure-safety theory.
Shape Control of Smart Beams Using PZT and SMA Actuators with the Spline Finite Point Method
Authors: Li Shuang Bei , Jiang Lin Jie , Mo Chunm Mei , Qin Rong
Published: October 2013

The spline finite point method (SFPM) that is based on the third order shear deformation beam theory (TSDT) is introduced to investigate the shape control of smart beam, which is integrated with PZT and SMA actuators. The governing equations of the smart beam are given by the SFPM and TSDT. The shape control problem is formulated as the problem of minimizing the objective function to study the shape control effects of the smart beam under the different control methods. To demonstrate the less computational cost and higher accuracy of the SFPM, several numerical examples are calculated. The advantages of both smart materials and the effective control of smart structure can be obtained by the hybrid actuators.
Numerical Study on the Plasma Generated by Different Discharge Modes at the Upstream of Fuel Jet in Scramjet Combustor
Authors: Zhou Si Yin , Nie Wan Sheng , He Bo , Che Xue Ke , Tian Xue Min
Published: October 2013

How to enhance the combustion and reduce the total pressure loss in scramjet combustor are very critical for the practical application of hypersonic aircraft. Based on the dominant thermal mechanism of arc plasma, the plasma generated in combustor is regarded as a promising method to improve the combustion. As a result, the combustor model with transverse fuel jet and plasma generated by two discharge modes at the upstream of flameholding cavity is established and it is used to study the mechanism of fuel mixing enhancement through numerical investigation. The results show that an oblique shock wave would be formed at the upstream of the pseudo small plasma hump, and interact with the separation shock wave induced by the transverse jet. This results in the recirculation zone at the upstream of fuel jet being enlarged obviously. Besides that, under the non-reaction flow conditions, the total pressure recovery coefficient increases due to the plasma generated. However, the total pressure recovery coefficient varies apparently and the shear layer above the cavity is fluctuant when the plasma is generated by periodical discharge mode. While under the reaction flow conditions, the shear layer develops thicker and the total pressure recovery coefficient decreases. And due to the existing of plasma, the mole fraction of product water increases. But compared with the steady discharge mode, the level of water is lower and the total pressure recovery coefficient decreases more under the periodical discharge mode. Though the plasma generated by steady discharge mode shows better performance in assisting combustion and reducing the pressure loss, considering the energy saving and the use of different parameters of the periodical discharge, the same effects of enhancing the fuel mixing through enlarging the recirculation zone located at the upstream of fuel jet and promoting the mass exchange of cavity can be reached. More numerical experiments have to be done to optimize the parameters of periodical discharge plasma to receive a best improvement on the performance of scramjet combustor.
Molecular Dynamics Approach and its Application in the Analysis of Multi-Scale
Authors: Gai Wen Hai , Guo R. , Guo Jun
Published: October 2013

Numerical simulation of the behavior of materials can be used as a versatile, efficient and low cost tool for developing an understanding of material behavior [. The numerical simulation methods include quantum mechanics, molecular dynamics, Voronoi cell finite element method and finite element method et al. These methods themselves are not sufficient for many fundamental problems in computational mechanics, and the deficiencies lead to the thrust of multiple-scale methods. The multi-scale method to model micro-scale systems by coupled continuum mechanics and molecular dynamics was introduced. This paper describes the basic methods of multi-scale and general simulation process of molecular dynamics was reviewed.
Modal Analysis of Wing Considering Transient Thermal Effects
Authors: Liu Hao , Sun Xia Sheng , Li Xiao Dong
Published: October 2013

The severe aerodynamic heating on the surface of modern hypersonic flight vehicle, that can bring high temperature and large temperature gradients in the structure of the vehicle, will be a challenge for the vehicles design and multidisciplinary optimization. The transient thermal environment consists of high temperature and large temperature gradients will generate two important problems related to vehicle structure, namely: 1) the material property, such as elastic modulus, will be degraded at elevated temperature, and 2) the non-uniform thermal stress cased by large temperature gradients will change the stiffness distribution of wing structure, which can make the modal frequencies and shapes of structure changed remarkably. Firstly, the theory and methodology of structure modal analysis in transient thermal environment is outlined. Subsequently, the transient temperature field of structure considering aerodynamic heating is obtained by employing computational technology of aerodynamic heating/structure heat transfer coupling program. Finally, the modal frequencies and shapes of vehicle structure under transient temperature field is calculated based on finite element method (FEM). Based on the analysis and investigation of the simulation results, the influence of the transient thermal environment on structure modal frequency and shape is determined. Furthermore, the investigation of wing structure modal analysis considering aerodynamic heating is an important basis of aerothermoelastic simulation.
A 3-node Shaft Element for Main Shaft Vibration FE Analysis
Authors: Bai Bing , Zhang Li Xing
Published: October 2013

To calculate the characteristics of the lateral vibration in the main shaft system of the hydro-turbine generating set, a three-node elastic shaft element was proposed. Its dynamic equation was derived and the interpolation function, translational inertia matrix, rotational inertia matrix, gyroscopic matrix and the stiffness matrix were obtained. Based on Matlab platform, a FEM program was developed for calculation and its correctness was verified through a numerical example. The study shows that, compared with the method using two-node shaft element, the results of the three-node shaft element are closer to the theoretical solution and the accuracy is higher.
Numerical Simulation on the Heat Transfer Performance of Multicrystalline Silicon in Directional Solidification Process
Authors: Yang Xi , Li Ming , Ma Wen Hui , Lv Guo Qiang , Luo Tao , Wang Yi Fei
Published: October 2013

The temperature distribution has important influence on the position and shape of solid-liquid interface during directional solidification process. So the calculation of temperature field is fairly significant for both structural analysis and temperature control. In this paper, the finite element method is applied to establish the 2D axisymmetric model for modeling the temperature distribution and the solid-liquid interface shape of multicrystalline silicon in semi-industrial directional solidification furnace. The numerical results show that the temperature field and solid-liquid interface shape can be controlled by adjusting the pulling rate in directional solidification process, and an optimized pulling rate of this system was obtained for large diameter silicon crystals with low defect density and uniform dopant distribution.
Analysis of Hydromechanics in a High-Consistency Conical Refiner
Authors: Liang Qian Hua
Published: October 2013

Analyzed the forces acting on the pulp in the refining zone of a high-consistency conical pulp refiner. A hydromechanics model for which presenting the flow of pulp along the plate has been derived through the calculation of the forces, which was composed two parts, since flat refining zone and conical refining zone formed the conical refiner.
Wet Modal Analysis of Cylindrical Pier under the Incentive of Fluid Excitation
Authors: Zhou Jie , Zhou Yi Tang , Li Rui , Ren Hui
Published: October 2013

Considering two-way fluid-structure interaction and using finite element software ANSYS simulation study of cylindrical pier at different flow rates caused by the interaction of the river and pier piers vibration problems, through the discrete solution of wet modal method, and combined with engineering example, the analysis results using Lanczos method extraction, introduction of green's function of point source, using the finite element-boundary element analysis wet modal and wet frequency of the structure. Numerical results show that: Frequencies of wet modal than no fluid medium under the influence of modal frequencies is much lower. So for underwater structures, when analysis the modal,it is must be considered the fluid influence of wet modal.
Elastic Parameters Measurement of Rubber by Digital Image Correlation
Authors: Zhang Rui
Published: October 2013

Application of Digital image correlation method (DIC) to measure the elastic modulus and Poisson ratio of rubber under compression is investigated in this paper. Surface images of the rubber surface subjected to various loading were captured using a CCD camera. DIC is subsequently used to obtain displacement field by correlating the images captured before and after deformation, and then the average compression strain is obtained by fitting the displacement using linear plane. The slope of each set of applied stress versus measured strain data is calculated by least-squares linear regression. The elastic modulus and Poisson ratio obtained from DIC, are compared to that determined from the dial gauge, which shows that they are in good accordance with existing data. Experimental results clearly show that DIC is suitable for accurate measurement the elastic modulus of rubber.
Finite Element Thermal Analysis of the Packing Container in Fire Environment
Authors: Huang Peng , Hao Zhi Ming , Li Wei Fen , Hu Shao Quan
Published: October 2013

The packing container is used in storage and transport of the high explosive (HE) material. The study concerns the safety of the packing container in fire environment. The spruce wood filled in the packing container can effectively resist heat transfer and protect HE material. The thermal analysis of the packing container in the pool fire environment is presented with the finite element method. When considering the water evaporation and the wood pyrolysis, the enthalpy curve of wood is presented in this study. Heat can be transferred from the fire to the packing container via convection and radiation. Thus, two thermal boundary conditions are applied to the thermal model of the packing container. The simulations show the inner temperature distributions of the packing container are significantly affected by the wood-column thickness. For the same time, the simulations show there is a slight difference in the char layer thickness between two thickness wood columns. The computed results show there are large temperature gradients in the interface of char and wood. This demonstrates the spruce wood is the excellent thermal resistance material.
Design and Research of Electronics Factory Evacuation Based on Computer Simulation Technology
Authors: Bai Lei
Published: October 2013

Along with the development of economy, a growing of large electronics workshop projects and the increasing of workshop area, the difficulties of evacuation design in engineering design is increasingly protruding. Due to large cubic construction and the complexity of building function, the evacuation problems in fire protection design is difficult to solve when using existing national specifications. By using the method of performance-based fire protection design in electronic workshop personnel evacuation design, and using computer simulation technology to demonstrate its security, we can find the solution to similar engineering problems.
A Numerical Study of the Fire-Extinguishing Performance of Ultrafine Water Mist in Small Scale Tunnel Space
Authors: Liang Tian Shui , Yu Jing Jing , Lu Guan Peng , Li Xiang , Zhong Wei , Lo Siu Ming
Published: October 2013

CFD simulation study on the fire-extinguishing performance of ultra-fine water mist (UFM) and its flow behavior in a small scale tunnel. Numerical simulation using dense gas model were carried outIt is discorvered that simulation shows that the larger size of fire is more difficult to extinguish in tunhenel space; and that the effect of obstruction in extinguishing efficiency depends on the location of obstruction.
Analysis of Factors Influencing the Development of Medical E-Commerce Based on ISM
Authors: Li Guo Gang , Kong Jing , Yin Zhe
Published: October 2013

The development of medical E-commerce is facing many challenges and constraints from government, businesses, individuals and other aspects. This paper, on the basis of the full investigation, elaborates Interpretative Structural Modeling (ISM) to make qualitative analysis. The modeling shows a clear hierarchical relationship between the various influencing factors and differentiates the surface factors, shallow factors, middle factors and underlying factors to expect to provide some suggestions for the development of medical E-commerce, and also lay the theoretical foundation for the quantitative analysis.
Cluster Analysis of Chinese Pictophonetic Characters Based on Pronunciation Indication of Sound-Elements
Authors: Hu Ren Fen , Cao Bing , Du Jian Yi
Published: October 2013

Most two-components Chinese characters are pictophonetic characters, which have one component to indicate the sound, named as the sound-element, while the other to convey the meaning, named as the meaning-element. With the development of speech sounds and character radicals, sound-elements cannot indicate the pronunciation precisely as before. In this paper, we will use similarity matrices to calculate the pronunciation indication of sound-elements, and classify pictophonetic characters with cluster analysis method. It is innovative to apply mathematical model to the research of Chinese characters, and our research will not only provide reference to normalization of modern Chinese characters, but also help to achieve better results in teaching or learning Chinese as a second language.
The Reliability Research of the Good Receipting and being Put in Storage Process of X City's Tobacco Logistics Distribution Center
Authors: Jin Jie , Yang Wei Ping
Published: October 2013

In this paper,X city's tobacco logistics distribution center is taken as a research subject.Firstly,the author used the availability analysis method to do the reliability analysis of the good receipting and being put in the storage process of this logistics system,a discrete model of the system's reliability based on the Markov process was being put forward .Then, the Markov state transition matrix was being worked out in order to get the computational formulas used to work out the steady state effectiveness and the failure rate of this system.Meanwhile, it also evaluated the reliability of this system and gave the improvement suggestions.
Probability Distribution of Flexural Fatigue Life for Glass Fiber Reinforced Concrete
Authors: Lv Yan , Cheng He Ming
Published: October 2013

Through the fatigue experiments of glass fiber reinforced concrete (GFRC) specimens with 0%0.6%0.8% and 1% glass fiber volume fraction, the fatigue-lives of GFRC at various stress levels were obtained. The results indicate that the statistical distribution of fatigue-life of GFRC is in agreement with the two-parameter Weibull distribution. According to the statistical analysis of fatigue-life,the study shows the fatigue life of GFRC follows both the two-parameter Weibull distribution and three-parameter Weibull distribution, but three-parameter Weibull distribution is more suitable for expressing the law. Besides, the S-N curves and P-S-N curves which can be used to determine the life of GFRC under constant amplitude fatigue load were obtained.The results indicate that GFRC has distinguished anti-fatigue property.
Simulation for Affect Factor of Curriculum Teaching System
Authors: Tian Jing , Zeng Yun
Published: October 2013

Main affect factors of curriculum teaching system are teaching rhythm ratio and learning damping of students. However, the lacks of appropriate methods research the relationship between two main factors and expressed characteristics of curriculum teaching system. Based on built physical model of curriculum teaching system in this paper, and refer to course assessment grade which is main expressed characteristics of curriculum teaching, the model parameterization is done. Taking course assessment grade of a teaching class as case, the distribution of learning damping, teaching rhythm ratio, and both of comprehensive influence are simulated by means of Matlab software. Simulation results show that learning damping and teaching rhythm ratio nearly submit to the law of normal distribution, and distribution between learning damping and teaching rhythm ratio is saddle-type.
The Decision-Making Method of Model Municipal Wastewater Treatment Plant Based on Cost Model and Hierarchical Structure Model
Authors: Xu Bing Feng , Liang Dong Hua , Lv Yan , Xu Yue
Published: October 2013

In this paper, three types of urban sewage treatment cost model, Oxidation ditch, ICEAS and A2/O are established respectively. The cost model and the analytic hierarchy process (AHP) were applied to sewage treatment plant for process optimization. It provides guidance for urban sewage treatment process decision-making.
Analysis of Geological Disasters Economic Evaluation
Authors: Zhan Qing Hua , Wang Shi Mei
Published: October 2013

This paper first introduces the meaning and mission of the economic evaluation of geological disasters,as well as the basic concepts of different economic evaluation, and then discuss the methods of economic evaluation of geological disasters, including multi-level fuzzy comprehensive evaluation method and statistical data evaluation method, and gives the outlook of the economic evaluation of geological disasters.
Analysis of Airworthiness Requirements on Fatigue Management Program in FAA
Authors: Zhao Kun , Wang Sheng Nan
Published: October 2013

As we know, the fatigue in metallic structures is getting more and more attention in many different countries. However, the current regulations are not systematic enough to determine how to manage a demonstrated risk due to fatigue. In 2011,FAA proposed the Advisory Circular (AC) 91-82A to develop the Fatigue Management Program (FMP) in order to establish a integrated fatigue management system. In this article, the author introduces the background and the concept of the demonstrated risk, also states the requirements in the process of developing and implementing the FMP. Nowadays, the cost of the new airplanes has meant that more fatigue management and more inspection actions should be taken in the process of assuring the safety of the continued airworthiness.
Application of Data Mining in CRM
Authors: Han Xue Xue , Lei Jin Hui , Zhao Xiao Xia , Luo Peng , Li Ju Fang
Published: October 2013

In the electronic commerce (e-commerce) environment, customer relationship management (CRM) is the core of e-commerce activities, and the customer in the CRM plays a vital role to the enterprise's development. Data mining technology can provide decision support for enterprises in the aspects such as the acquisition and maintaince of customers and the analysis of consumer satisfaction research research (CSR), to improve the market competitiveness of enterprises. This article tells the application of data mining techniques in some areas of CRM.
Dynamic Buckling of Single-Walled Carbon Nanotubes under Axial Impact Loading
Authors: Xiong Chuan An , Jiang Wu Gui
Published: October 2013

Based on the Budiansky-Roth motion criterion, a thin cylinder shell finite element model is established using the finite element software (ABAQUS) to systemically investigate the dynamic bucking behavior of single-walled carbon nanotubes, which is validated by the molecular dynamic model. It is shown that both the magnitude and duration of the impact load have a great influence on the critical buckling load. By comparing the buckling modes, it can be found that the stress wave propagation plays an important role on the buckling deformation. A local axisymmetrical buckling mode is observed at the beginning and then an asymmetrical buckling mode occurs because of the stress wave superposition.
Case Analysis of GM(1,N) Model in Predicting Kunming Real Estate Prices
Authors: Sun Yu Mei , Wu Li Guang
Published: October 2013

The price of real estate is influenced by many factors, and its the most important and the most direct reflection of the market of real estate,this study combines the historical prices with some other factors like the level of urbanization, based on that Kunming is the object of study, through establishing GM(1,N) model to forecast the Kunming real estate price, uses the method which combines the theory with empirical to research, and checks its accuracy, trying to make up for the short that we cant use the mathematic formula to describe the relation between the price and economically variables, compiling MATLAB command is to solve the tedious calculation of GM (1, N), hoping it can provide some guidance and scientific reference for the investment decision of the real estate.
MD Simulation on Evolution of Micro Structure and Failure Mechanism around Interactional Voids in Pure Al
Authors: Yuan Yu Quan , Chen Hua Yan , Zeng Xiang Guo , Hu Yan Fei
Published: October 2013

Experiments have shown that initial voids may exist in the manufacturing processes of pure aluminum, which adversely affect its mechanical properties. In this study, the process of plastic deformation around voids in pure aluminum was examined at atomic scale through molecular dynamics (MD) simulation. The Modified Embedded Atom Method (MEAM) was employed to characterize the atomic interactions in the pure aluminum with two voids. The calculation results revealed that the interaction of two voids endures three phases when the interval of the voids is increased: void coalescence, void coactions followed by the formation of a stress shield zone, and interaction vanishing. The critical parameters of the interval for the three phases were defined as well in this work. It was observed that crack initiated and further propagated near the voids along the slip systems of FCC crystal, which eventually caused structural failure. Meanwhile, the evolution of micro structure in the crack propagation process was investigated by means of Common Neighbor Analysis (CNA). The results showed that the phase transformation occurred near the voids during loading process.
Study on One Dimensional Mathematical Model for Unsteady Flow Sediment and Water Quality in Channel with a Sluice
Authors: Zhao Jin Qiong
Published: October 2013

Based on existing mathematical model for one-dimensional unsteady flow and non-uniform water-sediment, the inside boundary condition of sluice has been introduced to establish a mathematical model which is suitable for sediment and water quality in nontidal river channel with sluice, in combination with empirical model of local erosion-deposition and one-dimensional mathematical model for water quality. It can be used to simulate motion of water flow, sediment and pollutant under different operational modes of sluice in tidal reaches. In addition, a mathematical model calculation software for water-sediment and water quality has been developed on this basis after sluice has been built, which is also being used to study the influence of different application solution of sluice in Yongding New River on the motion of sediment and pollutant, so as to provide a basis for the selection of sluice operational modes.
FEM Analysis on a Tensile Loaded Copper Plate in Meso and Macro Scale
Authors: Gao Fei Hu , Chen Yong Jin , Guo Ran , Wang K. , Huang Y.
Published: October 2013

Under ABAQUS plateform, a tensile loaded pure copper plate is analyzed by FEM in mesoscale by means of Voronoi method and in macro scale by traditional method in statistical meaning. This conduct follows that, in the uniaxial tensile loaded plate, an uneven stress and strain field are produced with maximum stresses on the grain boundaries in mesoscale, compared with the stress and strain fields distributed continuously in macrostace as usually predicted. This reflects some of objective properties of polycrystalline material.
Mathematical Analysis for Wave Propagation Characteristics of Fluid-Filled Nonlocal Carbon Nanotubes
Authors: Yang Yang
Published: October 2013

The analytical nonlocal Euler-Bernoulli beam models for wave propagation in fluid-filled single-walled carbon nanotubes are established employing variation principle. The analytical nonlocal governing equations are derived and used in wave propagation analysis. Comparing with partial nonlocal Euler-Bernoulli beam models used previously, the novel analytical nonlocal models predict stiffness enhancement of CNT and wave decaying at high wavenumber or high nonlocal effect area. Though the novel analytical model is less sensitive than partial nonlocal model when fluid velocity is high, it simulate much high nonlocal effect than the corresponding partial model in many cases.
Influencing Factors Analysis of the Shock-Induced Separation for Supercritical Airfoil
Authors: Xu Xin , Liu Da Wei , Chen De Hua , Wang Yuan Jing
Published: October 2013

The shock-induced separation easily occurred on the upper surface of supercritical airfoil at transonic speeds, which would change the aerodynamic characteristics. The problem of the shock-induced separation was not solved completely for the complicated phenomena and flow mechanism. In this paper, the influencing factors of shock-induced separation for supercritical airfoil CH was analyzed at transonic speeds. The Navier-Stokes equations were solved, in order to investigate influence of different attack angles, Mach numbers and Reynolds numbers. The computation attack angles of CH airfoil varied from 0oto 7o, Reynolds numbers varied from 5×106to 50×106per airfoil chord while Mach number varied from 0.74 to 0.82. It was shown that the shock-induced separation was affected by attack angles, Mach numbers and Reynolds numbers, but the influence tendency and areas were quite different. The shock wave location and intensity were affected by the three factors, and the boundary layer thickness was mainly affected by Reynolds number, while the separation structure was mainly determined by the attack angle and Mach number.
A Numerical Study on the Large Compressive Deformations of Closed-Celled Rubber Foams
Authors: Fan Zhi Geng
Published: October 2013

Three dimensional (3D) cubic models with spherical pores ranged as Face-Centered Cubic (FCC) lattices are constructed to simulate the microstructures of rubber foams with various relative densities. The Mooney-Rivlin strain energy potential model is adopted to characterize the hyperelasticity of the constituent solid from which the foams are made. Large compressive deformations of closed-celled rubber foams are calculated by the iterative algorithm. Numerical results show that with the decreasing of foam relative densities, the effects of air pressures in cells on foam compressive stresses increase. When the ratio of initial Yangs modulus of cell material to the initial air pressure in cells reaches 2 order of magnitude, the influence of air pressures in cells can neglect.
Numerical Analysis on the Rapid Starting Period in a Screw-Type Centrifugal Pump
Authors: Cheng Xiao Rui , Li Ren Nian , Guo Wei Li , Zhang Nan , Gao Yang
Published: October 2013

Computational fluid dynamics were used to study the three-dimensional unsteady flows in a closed pipeline system with a screw-type centrifugal pump during rapid starting period. The unsteady Reynold time-averaged Navier-Stokes equations, RNG have been used to solve the unsteady, incompressible, viscous turbulent effects. The sliding mesh technique is proposed to resolve the transient flows caused by the started impeller. Combined with the characteristics of the motor, the screw-type centrifugal pump was started by two different way of linear and exponential acceleration. The automatic update of the rotational speed variation of field around the impeller was realized by FLUENT UDF. The transient variation of the pressure at the pump inlet and outlet, the global performance characteristics and the transient flow evolutions were obtained under different start-up modes. The results show that the rapid starting period presents obvious transient effect; the transient head, power curves changing with time reveal the transient attachment head and additional power part. Compared with the linear mode, the transient flow, shaft power, efficiency tend to a steady state value within a relatively short period in setting start time and maintain a quasi-periodic fluctuations.
Characteristics of Train Wind and Analysis of Personnel Safety in Double-Line Shield Tunnel
Authors: Fei Rui Zhen , Peng Li Min , Shi Cheng Hua , Yang Wei Chao
Published: October 2013

Based on the three-dimensional incompressible Navier - Stokes equations and the standard turbulent model, this paper develops a tunnel-air-train simulation model. Time-history variation rules and space distribution characteristics of train wind are studied at 200km per hour, and safety avoidance distance on evacuation passageways is further discussed. The results show that: Train wind is complex three-dimensional flow which is changed with time and space, since personnel safety may be threatened by train wind. Therefore, effective measures should be taken to avoid accidents.
An Object-Oriented Framework for Interface Stress Element Method
Authors: Feng Biao , Jin Bo , Lan Ri Qing , Chen Hao
Published: October 2013

This work describes our efforts towards building an object-oriented software framework for Interface Stress Element Method (ISEM), a newly developed numerical method for discontinuous and fracture problems. Based on the improved Interface Stress Element Method and object-oriented technology, we recognized major objects in ISEM and their interrelations. Then the class hierarchy, modules organization and data interfaces scheme were presented. We also addressed implementation issues and main features of this framework, which integrated a solver, a post-processor, a preprocessor and a model data converter. Numerical examples demonstrated that this system works well, which is a good starting point for further development.
Dynamic Stall Control by Undulatory Deformation
Authors: Ge Lan , Hu Wen Rong
Published: October 2013

Dynamic stall can delay the stall of wings and airfoils that are rapidly pitched beyond the static stall angle. A new method of active dynamic stall control by the undulatory foil was proposed in this paper. The study was based on solving unsteady Reynolds-Average Navier-Stokes equations. Comparisons of the effectiveness of pitching foils and undulatory foils on dynamic stall control in both light stall and deep stall were conducted. The undulatory foils with various controllable parameters were further discussed. The results showed that the performance of undulatory foils is much better than that of the rigid pitching foil at high angles of attack either in the light stall or in the deep stall situation.
Research on the Optimization Design of Supersonic Swirling Separator
Authors: Li Ke Xin , Eri Qi Tai , Yan Chen Yang , Ji Wei An , Su Pei Ran
Published: October 2013

Supersonic swirling separator had a good ability in separating gas-liquid. In this paper, the Laval-nozzle and straight-tube of the non-central cone supersonic swirling separator were optimized designing. The separation performance of the optimized supersonic swirling separator was researched by CFX. The results show that,with the relative pressure ratio decreasing, the shock waves which occurred in the diffuser moved towards the extraction device, the maximum Mach number decreasing. When the relative pressure ratio down to 1.4, the outlet total pressure recovered to 73% of the inlet total pressure, the flow in the divergent section of Laval-nozzle and the straight-tube was supersonic, the lowest temperature can be down to-84.5°C and the maximum centrifugal acceleration was 261,800g, which provided a swirling and cold environment for the separation of gas-liquid; With the straight-tubes length-diameter ratio increased, a normal shock wave occurred in the straight-tube. Further increased the length-diameter ratio, the normal shock wave moved towards the throat and the strength of the shock wave was increasing, which was a disadvantage to the separation of the gas-liquid.
Numerical Simulation on Circular-Arc Grid-Fin Configurations
Authors: Li Yong Hong , Shan Ji Xiang , Su Ji Chuan , Huang Yong
Published: October 2013

A grid fin is an unconventional lifting and control surface which consists of an outer frame with an inner grid of intersecting planar surfaces of small chord. Normal shocks form at the back of the lattice cells at transonic Mach numbers thus choking the flow through the cells and causing a significant reduction in lift force and increase in drag force. An improved circular-arc grid-fin configuration is proposed in the present study to reduce transonic flow choking. Viscous computational fluid dynamic simulations were performed to investigate flows over single baseline and circular-arc grid fins and body-fin configurations under transonic and supersonic flow with Mach numbers in the range of 0.6-4.0. The present numerical results indicate the drag coefficient on single circular-arc grid fin and body-fin configuration is decreased by approximately 10%-24% and 8% respectively for all the Mach numbers investigated in the present study.
Numerical Simulation on VIV of a Spring-Mounted Rigid Cylinder through Fully Coupling with Fluid
Authors: Luo Zhu Mei , Zhang Li Xiang
Published: October 2013

In this paper, the fluid and structure model are fully coupled and put into FSI solver to calculate simultaneously to predict vortex-induced vibration. Multiple iterative calculations are needed in each time step and the fluid and structure model perform the next step calculation until satisfy the requirement of accuracy, which is different from conventional method used to simulate VIV. The present results agree well with the experimental results of other researchers.
Simulation of Particle Reinforced Composite Materials in Macro- and Meso-Scales
Authors: Guo Jun , Guo Ran , Gai Wen Hai
Published: October 2013

A simulation method of macro-and meso-scales is developed for particle reinforce composite materials. The two-scale modeling based on homogenization theory enables to formulate the macro scale problem with Finite Element Method (FEM), while the meso-scale one with Voronoi Cell Finite Element Method (VCFEM). Dangerous regions are identified in macro scale computing period, which lately be meshed into Voronoi Cells in meso-scale period to get a more accurate solution. Representative numerical examples are presented to demonstrate the capability of the proposed two-scale analysis method of particulate reinforce composite materials.
Numerical Simulation Research on Aerodynamic Characteristics of the Fixed Transition Airfoil
Authors: Shan Ji Xiang , Huang Yong , Ma Xiao Yong , Li Yong Hong , Bai Jie
Published: October 2013

In wind tunnel tests, the size of the test model is generally much less than the real aircraft, which makes that the Re number during the test is an order of magnitude smaller than the flight Re number. The fixed transition is an important means to improve the test Re number. In the paper, the transition turbulence modelis used to simulate the flow characteristics of the test model (Re=1.5×106), flight model (Re=12×106) and fixed transition model. It is shows that the drag coefficient of the transition model increases and the lift coefficient decreases to compare with the test model and flight model. Compared with the flight model, the turbulent velocity profile of transition model in layer boundary is inadequate, its relative Re number is smaller, so the further amend in the aerodynamic characteristics need to be made.