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溶质梯度影响非等温凝固过程的相场法模拟

系统仿真学报 2009年第10期21卷 3088-3091页

作者：朱昌盛杨世银王智平肖荣振兰州理工大学CAD中心兰州730050 兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室兰州730050

采用相场法模拟了Ni-Cu二元合金非等温凝固过程溶质梯度对枝晶生长的影响。结果表明:非等温凝固时,潜热的释放使固相区的温度比液相中的高,在二次枝晶生长较为密集的中心区域温度最高,固相区温度升高会使得金属重熔,发生重熔现象,晶体... 详细信息

采用相场法模拟了Ni-Cu二元合金非等温凝固过程溶质梯度对枝晶生长的影响。结果表明:非等温凝固时,潜热的释放使固相区的温度比液相中的高,在二次枝晶生长较为密集的中心区域温度最高,固相区温度升高会使得金属重熔,发生重熔现象,晶体的生长速度和凝固区域的温度随之出现波动。溶质梯度对溶质分布影响较大,溶质梯度增加,固相率提高,溶质分配系数k增大,固相区溶质富集,形成了过饱和的固相,溶质截流效应明显。

关键词：相场法非等温凝固溶质梯度溶质截流

Wavefront reconstruction algorithm for wavefront sensing based on binary aberration modes

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Chinese Physics B 2017年第5期26卷 153-159页

作者：庞博清王帅程涛孔庆峰文良华杨平 key laboratory on Adaptive Optics Chinese Academy of Sciences Chengdu 610209 China University of Chinese Academy of Sciences Beijing 100049 China The Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209 China School of Optoelectronic information University of Electronic Science and Technology of China Chengdu 610209 China School of Physics and Electronic Engineering Yibin University Yibin 644000 China

We propose a new algorithm for wavefront sensing based on binary intensity modulation. The algorithm is based on the fact that a wavefront can be expended with a series of orthogonal and binary functions, the Walsh series. We use a spatial light modulator（SLM） to produce different binary-intensity-modulation patterns which are the simple linear transformation of the Walsh series. The optical fields under different binary-intensity-modulation patterns are detected with a *** relationships between the incident wavefront modulated with the patterns and their optical fields are built to determinate the coefficients of the Walsh series. More detailed and strict relationship equations are established with the algorithm by adding new modulation patterns according to the properties of the Walsh functions. An exact value can be acquired by solving the equations. Finally, with the help of phase unwrapping and smoothing, the wavefront can be reconstructed. The advantage of the algorithm is providing an analytical solution for the coefficients of the Walsh series to reconstruct the wavefront. The simulation experiments are presented and the effectiveness of the algorithm is demonstrated.

关键词： wavefront aberration Walsh modulated reconstructed optics incident smoothing Zernike modulator

Empirical-Statistical Models Based on Remote Sensing for Estimating the Volume of Landslides Induced by the Wenchuan Earthquake

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Journal of Mountain Science 2011年第5期8卷 711-717页

作者： FAN Jianrong LI Xiuzhen GUO Fenfen GUO Xiang key laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment CAS Chengdu 610041 China

The Wenchuan Ms 8.0 earthquake on May 12, 2008 induced a huge number of landslides. The distribution and volume of the landslides are very important for assessing risks and understanding the landslide - debris flow - barrier lake - bursts flood disaster chain. The number and the area of landslides in a wide region can be easily obtained by remote sensing technique, while the volume is relatively difficult to obtain because it requires some detailed geometric information of slope failure surface and sub-surface. Different empirical models for estimating landslide volume were discussed based on the data of 107 landslides in the earthquake-stricken area. The volume data of these landslides were collected by field survey. Their areas were obtained by interpreting remote sensing images while their apparent friction coefficients and height were extracted from the images unifying DEM (digital elevation model). By analyzing the relationships between the volume and the area, apparent friction coefficients, and the height, two models were established, one for the adaptation of a magnitude scale landslide events in a wide range of region, another for the adaptation in a small scope. The correlation coefficients (R2) are 0.7977 and 0.8913, respectively. The results estimated by the two models agree well with the measurement data.

关键词： 5.12 Wenchuan earthquake Landslides Remote sensing Volume Estimation model

Analysis of Power Propagation Along Coated Metal Wire at Terahertz Frequencies

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Analysis of Power Propagation Along Coated Metal Wire at Ter...

2011年全国微波毫米波会议

作者： Zhihui Wang~(1,2) Yong Zhang~(1,2) Ruimin Xu~1 (1 School of Electronic Engineering,University of Electronic Science and technology of china,Chengdu,611731 2 National key laboratory of Monolithic Integrated Circuits and Modules,Nanjing,210016,china)

＜正＞In this paper,the propagation characteristics of coated wire are studied under the framework of the Sommerfeld model at terahertz *** effective permittivity constant,characteristic impedance and propagation attenuation have been analyzed by numerically solving the complex eigenvalue equation for the propagation constant at *** energy distribution characteristics of coated wire with different dimensions and materials are also discussed at *** investigation results show that the coated wire is a promising broadband THz transmission line with low loss and high energy concentration for terahertz near-field imaging, spectroscopy,and sensing application.

关键词： Terahertz radiation transmission line Sommerfeld wave

The traffic information fusion method based on the multisource detectors

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The traffic information fusion method based on the multisour...

第24届中国控制与决策会议

作者： Wenlong Peng 1,2 , Limin Jia 1,2 , Junqing Tang 1 , Liangping Liu 1,2 , Honghui Dong 1,2* 1. School of Traffic and Transportation, beijing Jiaotong University, beijing 1000442. state key laboratory of Rail Traffic Control and Safety, beijing Jiaotong University, beijing 100044

Recently, traffic problem has become one of the major problems in the world’s governments including china. People urgently need to know the actual operating status of the road network traffic so that it can guide people commute travel. The development of traffic detection technique makes it possible for people to get the traffic flow foundation information. Information fusion technology can remove redundant, overcome the ambiguity and get more comprehensive, more accurate and more reliable information than any individual data sources. In this paper we mainly discussed the BP neural network traffic information fusion method and procedures based on the existing research results and beijing traffic situation.

关键词： Multisource detector Data confusion Neural network

Origins and fates of CO2 in the Dongying Depression of the Bohai Bay Basin

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Origins and fates of CO2 in the Dongying Depression of the B...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Liuping zhang~(1*),Aiguo Wang~1 and Zhijun Jin~2 ~1key laboratory of Petroleum Resource,Institute of Geology and Geophysics, Chinese Academy of Science,beijing 100029,china. ~2Research Institute of Petroleum Exploration and Development,SINOPEC, beijing 100083,china

Co gas reservoirs have been found in a series of rift basins in East *** objective of this study is to reveal origins and fates of CO in the Dongying Depression in East china by using isotopic(He and C) and molecular ***/He,CO/He andδC(CO)),values indicate that the CO gases with CO>79%in the deep fault belts in the depression are predominantly *** contrast,CO in most gases in the relative stable areas,where source rocks are developed,is less than 10%.Based on helium isotope andδC(CO))O/He diagram,it was found that 10-30%of these CO gases is mantle-derived,28%to 68%is limestone-decomposed and 18%to 54% sedimentary organic in the relative stable *** mantle-derived and limestone-decomposed CO in the relative stable areas indicates that the mantlederived geo-fluid met the source *** hydrocarbons can be generated via its heat influence. As the previously published model is not suitable for study of C0 fates at least in the case of thermogenic CO addition,we proposed two models for CO addition and loss:modelⅠfor CO loss and limestone-decomposed CO addition and modelⅡfor CO loss and addition of sedimentary organic CO,based on aδC(CO))～CO/He *** using the new models,it was revealed that the loss rates of mantle-derived CO can be as high as 50-99.99%for most gases in the depression,the addition rates of limestone-decomposed CO range from 18%to 150%,and the addition rates of sedimentary organic CO from 11%to 230%.From this study,it was revealed that more *** entered the Dongying Depression than previously recognized.

关键词： Carbon dioxide Origin Fate Helium Carbon Isotope

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应用扩张矩阵理论的攻击特征提取

计算机科学 2010年第4期37卷 49-51,74页

作者：陈志贤黄皓南京大学软件新技术国家重点实验室南京210093 南京工业大学电子与信息工程学院南京210009

近年来随着因特网的飞速发展,计算机系统也面临着越来越多的安全威胁。国内外不少研究人员为此提出了许多种基于软计算的方法用于检测网络攻击。给出了一种基于扩张矩阵理论的攻击特征提取方法,通过构造攻击子集和正常子集的扩张矩阵,... 详细信息

近年来随着因特网的飞速发展,计算机系统也面临着越来越多的安全威胁。国内外不少研究人员为此提出了许多种基于软计算的方法用于检测网络攻击。给出了一种基于扩张矩阵理论的攻击特征提取方法,通过构造攻击子集和正常子集的扩张矩阵,建立其最优特征子集选择的整数规划模型,并利用简单遗传算法求解,最终生成可用于检测特定类型攻击的最优规则。在KDD Cup99数据集上的实验结果表明,该方法具有较高的正确检出率和可接受的低误报率。

关键词：扩张矩阵特征子集选择遗传算法入侵检测

Preparation and Properties of Sintering Additives Coated Si_3N_4 from Heterogeneous Nucleation Processing

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Journal of Materials Science & technology 2002年第1期18卷 34-36页

作者： Juxian ZHANG, Jinjun FENG and Longqiao GAObeijing Vacuum Electronics Research Institute, 100016 beijing, china[ Manuscript received January 18, 2001, in revised form April 24, 2001] beijing Vacuum Electron. Res. Inst. Beijing 100016 China

The sintering additives such as Al2O3 and/or Y2O3 were coated on the surfaces of Si3N4 particles via heterogeneous nucleation processing using a buffered pH solution as the precipitation reagent. They nucleated and grew only on the surfaces of Si3N4 and did not form sol particles in solution by TEM observation. The isoelectric point (IEP) of coated Si3N4 was different from that of as-received Si3N4. The IEP of AI(OH)3-coated Si3N4 occurred at pH8.4, which is close to that of alumina. When AI(OH)3-coated Si3N4 particles were coated with Y(OH)3, the IEP of coated Si3N4 powder shifted from pH8.4 to pH9.2, similar to that of yttria. In addition, the rheological data showed that Al2O3 and/or Y2O3 coated Si3N4 suspension is nearly Newtonian and that added Si3N4 suspension shows a shear rate thinning behavior.

关键词： Si3N4 powder Sintering additives Zeta potential Rheological property

5-Hydroxydecanoate inhibits proliferation of hypoxic human pulmonary artery smooth muscle cells by blocking mitochondrial KATP channels

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5-Hydroxydecanoate inhibits proliferation of hypoxic human p...

湖北省暨武汉市病理生理学会第十四届学术年会

作者： Tao WANG~2,Zhen-xiang ZHANG~(2,4),Yong-jian XU~2,Qing-hua HU~3 2 Department of Respiratory Medicine,Tongji Hospital,Tongji Medical College,Huazhong University of Science and technology,Wuhan 430030,china 3 key laboratory of Pulmonary Diseases of the Ministry of Health of china and Department of Pathophysiology,Tongji Medical College,Huazhong University of Science and technology,Wuhan 430030,china

Aim:To study the effect of 5-hydroxydecanoate(5-HD)on the proliferation of 24 h hypoxic human pulmonary artery smooth muscle cells(HPASMC)and to explore the pharmacological mechanisms of 5-HD as an inhibitor of mitochondrial membrane ATP-sensitive potassium channel activation. Methods:Normoxic or hypoxic HPASMC in culture were stimulated by either diazoxide or 5-HD for 24 *** proliferation of HPASMC was examined by 3-(4,5-dimethyl-2-thiazol-yl)-2,5-diphenyl-2H -tetrazolium bromide(MTT)assay and proliferating cell nuclear antigen(PCNA) immunohistochemistry *** apoptosis of HPASMC was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)assay and flow cytometric *** relative changes in mitochondrial membrane potential(△Ψm)were measured using the rhodamine fluorescence(R-123)***:Both hypoxia and diazoxide stimulation increased△Ψm value measured by the absorbance of MTT,PCNA-positive staining and decreased TUNEL-positive staining and apoptotic cells in *** and the concomitant stimulation of diazoxide obviously enhanced the effects of hypoxia or diazoxide alone.5-HD significantly attenuated the effects in each of the above ***,5-HD partially inhibited the effect of hypoxia on R-123 fluorescence intensity in ***:5-HD can inhibit the proliferation of hypoxic HPASMC by blocking mitochondrial Kchannels.

关键词： pulmonary artery smooth muscle cell hypoxia 5-hydroxydecanoate mitochond-rial membrane ATP-sensitive potassium channel