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Prediction of Grain Size for Blade Precision Forging Process under Thermo-Mechanical Coupling

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Prediction of Grain Size for Blade Precision Forging Process...

The Fourth International Conference on Physical and Numerical Simulation of materials (ICPNS’2004)

作者： He YANG Yuli LIU. Wang CAI and Mei ZHAN college of materials science and engineering. Northwestern Polytechnica! university.Xi’an 710072. china

＜正＞Blade precision forging is a high temperature and large plastic deformation process. Interact of deformation and heat conduction results in producing large temperature unevenness inside the billet. The unevenness has a great effect on the mechanical property and microstructure of the forged blade. However, internal quality of the blade is decided by its microstructure. it is necessary to conduct a research on the microstructure of the blade forging process. Taking a blade with a tenon as an object, its precision forging process is simulated and analyzed using a 3D coupled thermo-mechanical FEM code. And based on the prediction model of Ti-6Al-4V presented by the predecessor, a study of the evolution of grain size in the forging process is made. The distribution characteristics of grain size in typical sections are obtained under various deformation degrees. This study may provide a base for designing the blade forging process and working out its parameters.

关键词： Blade Precision forging Grain size Prediction

Determination of standard molar enthalpies of formation of complexes involving rare earth chloride with glycine

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Determination of standard molar enthalpies of formation of c...

中国化学会第十五届全国化学热力学和热分析学术会议

作者： Lingling Zhang Xia Li Jinting Tan Xuwu Yang~* college of Chemistry and materials science Northwest university Xi’an 710069 PR china

Great interest has been aroused in the study of the complexes of rare earth salts with amino acids because of their physiological and biochemical effects in a living *** this paper,the consta

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AN ENABLING ENVIRONMENT FOR MULTIDISCIPLINARY APPLICATION SIMULATIONS

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AN ENABLING ENVIRONMENT FOR MULTIDISCIPLINARY APPLICATION SI...

中国力学学会学术大会'2005

作者： Zheng Yao Xie Lijun (Center for engineering and Scientific Computation, and college of Computer science, Zhejiang university, Hangzhou 310027, china)

A Problem Solving Environment (PSE) is a computer system that provides all the computational facilities necessary to solve a target class of problems. Typically, it can reduce the difficulty of physical simulation by utilizing user natural languages and application specific terminology, and by automating many lower level computational tasks. We define a kind of PSEs in the following formula:PSE = User interface + Enabling libraries and tools + Problem solvers + Software busCommonly, a PSE should have a friendly user interface such as nature language and graphical userinterface that can help the user to use the system in a direct and efficient manner. Enabling libraries and tools arethe most valuable parts of a PSE. They provide all the necessary assistant functions for a simulation, such asgeometric modeling, mesh generation, and scientific visualization. Problem solvers are integrated into the

关键词： parallel computing problem solving environment enabling environment

The application of ultrasonic phase spectrum of the reflection coefficient on nondestructive characterizing the plasma sprayed coatings irradiated by HIPIB

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The application of ultrasonic phase spectrum of the reflecti...

Fifth International Conference on Surface engineering

作者： Y.ZHAO1,L.LIN1,X.M.LI1,M.K.LEI1 1 NDT & E Laboratory,School of materials science & engineering,Dalian university of technology,Dalian 116024,P.R.china 2 Surface engineering Laboratory,School of materials science & engineering,Dalian university of technology,Dalian 116024,P.R.china

Ultrasonic phase spectrum of reflection coefficient has been used to nondestructively characterize the density,porosity,and microcracks of plasma sprayed Cr2O3 coatings irradiated by high-intensity pulsed ion beam(HIPIB).The ultrasonic measurement was investigated using immersion focusing pulse echo method with a 25 MHz transducer and the phase spectrum of reflection coefficient has been experimentally *** relationship among velocity,density,attenuation coefficient and the phase spectrum was analyzed based on an acoustic transmission model in a multi-layered *** velocity relates to the harmonic frequency of the phase spectrum,and the density and attenuation coefficient play roles on the amplitude of the maximum and the shape of the *** effects of the three parameters(velocity,density and attenuation coefficient) on the amplitude of the maximum of the phase are *** critical value exists which change the relationship between the individual parameter and the *** one of the three parameters exceeds the corresponded critical value,the amplitude of the maximum decreases in the same form of y=Aexp(Bxn).For the as-sprayed and irradiated coatings with the thickness of 50 μm,the velocity calculated from the phase spectrum is 2522 m/s and 2772 m/s,harmonic frequency corresponding to 12.61 MHz and 13.86 MHz,*** ultrasonic determinations demonstrated that the coating became more densified after irradiation by HIPIB,which are in agreement with SEM *** phase spectrum itself is a good indicator to reveal differences between density and microstructures of coating prepared with various conditions as well as to follow their evolution after HIPIB *** method developed has found application in the problem of characterizing the coatings.

关键词： Ultrasonic Characterization Reflection Coefficient Phase Spectrum Cr2O3 Coatings Density

基于时间Petri网的工作流用户管理系统的建模及分析

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系统仿真学报 2008年第S2期20卷 118-122页

作者：吕楠吴哲辉傅游山东科技大学信息科学与工程学院青岛266510

用Petri网对系统进行建模分析可以揭示被模拟系统在结构和动态行为方面的许多重要信息。首先定义了工作流到Petri网的映射方法;然后结合实际应用设计了一个基于Petri网的天气预报用户管理系统模型,分析验证了该模型的可行性和合理性;最... 详细信息

用Petri网对系统进行建模分析可以揭示被模拟系统在结构和动态行为方面的许多重要信息。首先定义了工作流到Petri网的映射方法;然后结合实际应用设计了一个基于Petri网的天气预报用户管理系统模型,分析验证了该模型的可行性和合理性;最后在此模型的基础上,考虑时间因素给出了一种改进的时间Petri网模型,并定量分析了天气预报用户管理系统中每个可能流程的时间性能。

关键词：用户管理工作流时间Petri网模型性能分析

维普期刊数据库

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稀土超长余辉材料及其涂料的研究

中国稀土学报 2003年第2期21卷 155-158页

作者：孙彦彬邱关明王安平陈永杰东北大学材料与冶金学院辽宁沈阳110006 长春光机学院材料系吉林长春130022 吉林大学材料科学与工程学院吉林长春130026 沈阳化工学院化学系辽宁沈阳110021

以碳酸锶、氧化铝、氧化铕和氧化镝为原料,用高温固相反应法合成了稀土超长余辉发光材料SrAl2O4∶Eu2+,Dy3+。测试了该发光材料的激发光谱、发射光谱、余辉亮度及余辉时间,激发光谱主峰分别位于320和360nm处,激发波长的范围较宽,从紫外... 详细信息

以碳酸锶、氧化铝、氧化铕和氧化镝为原料,用高温固相反应法合成了稀土超长余辉发光材料SrAl2O4∶Eu2+,Dy3+。测试了该发光材料的激发光谱、发射光谱、余辉亮度及余辉时间,激发光谱主峰分别位于320和360nm处,激发波长的范围较宽,从紫外到可见光区均可激发该发光材料。发射光谱的主峰位于520nm,发光颜色为黄绿色,余辉可达16h以上。解释了超长余辉发光材料的发光机制。以苯丙乳液为成膜物,添加适量的发光粉及适当的助剂研制出一种超长余辉发光涂料。确定出了该涂料的最佳配方,测定了涂料的各种性能,并对影响涂料性能的主要因素进行了探讨。

关键词：光学超长余辉发光材料发光涂料稀土

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Functions and mechanisms of the CBL-CIPK signaling system in plant response to abiotic stress

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Progress in Natural science:materials International 2009年第6期19卷 667-676页

作者： Ruifen Li a,1, Junwen Zhang a,b,1, Jianhua Wei a, Hongzhi Wanga, Yanzhen Wanga, Rongcai Ma a, a Beijing Agro-Biotechnology Research Center, Beijing Academy of Agriculture and Forestry sciences, Beijing 100097, china b Life science college, Capital Normal university, Beijing 100037, china Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China Life science college Capital Normal University Beijing 100037 China

To cope with environmental stimuli, plants have evolved precise regulatory mechanisms to perceive, transduce and respond to abiotic stresses that can negatively affect growth and development. The CBL-CIPK signaling system is a newly emerging plant-specific and Ca2+-dependent network mediating abiotic stress tolerance. CBLs may sense a Ca2+ signature triggered by abiotic stresses, and have specific interactions with novel CIPK-type kinases after binding Ca2+. The CBL/CIPK complexes may post-translationally phosphory-late downstream target proteins to regulate abiotic stress tolerance in a cell or tissue-specific manner. In some cases transcription factors are induced to activate stress-responsive genes that control adaptation reactions. The CBL-CIPK signaling system exhibits specificity, diversity and complexity. Meanwhile, cross talk also exists in the CBL-CIPK signaling. To date, significant progress has been made in the role of the CBL-CIPK signaling system in responding to salt, low K+ and to high pH, which will provide a fast and efficient method of molecular design breeding combined with the CBL/CIPK engineering of crop plants, for enhanced tolerance to abiotic stresses. However, more CBL/CIPK components remain to be identified, particularly from specific plants that grow in conditions with abiotic stress, and the specificity of their abiotic stress signaling will need to be dissected.

关键词： Calcium signal CBL CIPK Signal transduction Abiotic stress

Research on an efficient method of license plate location

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Research on an efficient method of license plate location

2010 International Colloquium on Computing,Communication, Control, and Management (CCCM2010)

作者： Yuren Du Information engineering college Yangzhou university Yangzhou,china Wen Shi Caiyun Liu Information engineering college Yangzhou university Yangzhou,china

In the application of intelligent transportation system(ITS),license plate(LP) location is one of the most crucial *** view of illumination variance,noise,complex and dirty background,this paper presents a license plate location method,which based on edge information analysis with a preprocessing *** plate area contains rich edge and texture information,which can be used to detect a number plate *** results demonstrated the great robustness and efficiency of our method.

关键词： license plate location image enhancement edge extraction segmentation

Robust Fractional Order Differentiator

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Robust Fractional Order Differentiator

第24届中国控制与决策会议

作者： Dali Chen, YangQuan Chen, Dingyu Xue college of Information science and engineering, Northeastern university, Shenyang, 110004, china 2.Center for Self-Organizing and Intelligent Systems (CSOIS), Department of Electrical and Computer engineering, Utah State university, Logan, UT 84322-4160 USA 3.college of Information science and engineering, Northeastern university, Shenyang, 110004, china

A robust fractional order differentiator is proposed to estimate the fractional order derivative of the given contaminated signal. Least square polynomial fitting technique is used to minimize the noise and Griinwald-Letnikov definition is used to calculate the fractional order derivative. A concise method is proposed to speed up the computation time and a parameter setting strategy is present for user. The frequency domain analysis demonstrates that the proposed differentiator essentially is a fractional order low-pass filter. The accuracy and robustness are evaluated by the experiments.

关键词： Fractional Order Differentiator Robust Least Squares.