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YIG铁氧体单晶/薄膜生长工艺及成线技术 被引量:3
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作者 何水校 《磁性材料及器件》 CAS CSCD 2002年第2期22-24,共3页
简要介绍了YIG铁氧体块状单晶和YIG单晶薄膜常见的生长方法,重点报道了助熔剂法和液相外延工艺,最后对YIG铁氧体块状单晶和单晶薄膜的科研工艺线建设提出了切实可行的方案。
关键词 YIG 铁氧体 成线技术 钇铁石榴石 单晶生长 单晶薄膜 助熔剂法 液相外延 生产技术
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Agenesis of the dorsal pancreas 被引量:3
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作者 Lale Pasaoglu Murat Vural +2 位作者 Hatice Gul Hatipoglu Gokce Tereklioglu Suha Koparal 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第18期2915-2916,共2页
Developmental anomalies of the pancreas have been reported but dorsal pancreatic agenesis is an extremely rare entity. We report an asymptomatic 62-year-old woman with complete agenesis of the dorsal pancreas. Abdomin... Developmental anomalies of the pancreas have been reported but dorsal pancreatic agenesis is an extremely rare entity. We report an asymptomatic 62-year-old woman with complete agenesis of the dorsal pancreas. Abdominal computed tomography (CT) revealed a normal pancreatic head, but pancreatic body and tail were not visualized. Magnetic resonance imaging (MRI) findings were similar to CT. At magnetic resonance cholangiopancreatography (MRCP), the major pancreatic duct was short and the dorsal pancreatic duct was not visualized. The final diagnosis was dorsal pancreatic agenesis. 展开更多
关键词 AGENESIS Pancreatic anomaly Computed tomography Magnetic resonance cholangiopancreatography
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Control synthesis for polynomial nonlinear systems and application in attitude control 被引量:1
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作者 Chang-fei TONG Hui ZHANG You-xian SUN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第6期833-839,共7页
A method for positive polynomial validation based on polynomial decomposition is proposed to deal with control synthesis problems. Detailed algorithms for decomposition are given which mainly consider how to convert c... A method for positive polynomial validation based on polynomial decomposition is proposed to deal with control synthesis problems. Detailed algorithms for decomposition are given which mainly consider how to convert coefficients of a polynomial to a matrix with free variables. Then, the positivity of a polynomial is checked by the decomposed matrix with semidefinite programming solvers. A nonlinear control law is presented for single input polynomial systems based on the Lyapunov stability theorem. The control synthesis method is advanced to multi-input systems further. An application in attitude control is finally presented. The proposed control law achieves effective performance as illustrated by the numerical example. 展开更多
关键词 Nonlinear control Attitude control Polynomial systems
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Smooth cutting pattern generation technique for membrane structures using geodesic line on subplane and spline interpolation 被引量:1
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作者 SHON Su-deok LEE Seung-jae LEE Kang-guk 《Journal of Central South University》 SCIE EI CAS 2013年第11期3131-3141,共11页
Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approxim... Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approximation methods were used to flatten the strip for the generation of a smooth pattern.This search approach is very simple,and the geodesic line could be easily attained by the proposed method without the need for a difficult computation method.Smooth cutting patterning can also be generated by spline approximation without the noise in discrete nodal information.Additionally,the geodesic cutting pattern saved about 21%of the required area for the catenary model due to the reduction of the curvature of the planar pattern seam line. 展开更多
关键词 membrane structures cutting pattern generation geodesic line spline interpolation triangular mesh sub-plane
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An Integrated Tool for Power/Ground Network Design, Optimization,and Verification for Cell Based VLSIs
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作者 傅静静 武晓海 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第3期266-273,共8页
A CAD tool based on a group of efficient algorithms to verify,design,and optimize power/ground networks for standard cell model is presented.Nonlinear programming techniques,branch and bound algorithms and incomplete ... A CAD tool based on a group of efficient algorithms to verify,design,and optimize power/ground networks for standard cell model is presented.Nonlinear programming techniques,branch and bound algorithms and incomplete Cholesky decomposition conjugate gradient method (ICCG) are the three main parts of our work.Users can choose nonlinear programming method or branch and bound algorithm to satisfy their different requirements of precision and speed.The experimental results prove that the algorithms can run very fast with lower wiring resources consumption.As a result,the CAD tool based on these algorithms is able to cope with large-scale circuits. 展开更多
关键词 VLSI power/ground network nonlinear programming techniques ICCG branch and bound CAD tool
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A nonlinear PCA algorithm based on RBF neural networks 被引量:1
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作者 杨斌 朱仲英 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期101-104,共4页
Traditional PCA is a linear method, but most engineering problems are nonlinear. Using the linear PCA in nonlinear problems may bring distorted and misleading results. Therefore, an approach of nonlinear principal com... Traditional PCA is a linear method, but most engineering problems are nonlinear. Using the linear PCA in nonlinear problems may bring distorted and misleading results. Therefore, an approach of nonlinear principal component analysis (NLPCA) using radial basis function (RBF) neural network is developed in this paper. The orthogonal least squares (OLS) algorithm is used to train the RBF neural network. This method improves the training speed and prevents it from being trapped in local optimization. Results of two experiments show that this NLPCA method can effectively capture nonlinear correlation of nonlinear complex data, and improve the precision of the classification and the prediction. 展开更多
关键词 Principal Component Analysis (PCA) Nonlinear PCA (NLPCA) Radial Basis Function (RBF) neural network Orthogonal Least Squares (OLS)
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Reconstruction based approach to sensor fault diagnosis using auto-associative neural networks 被引量:4
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作者 Mousavi Hamidreza Shahbazian Mehdi +1 位作者 Jazayeri-Rad Hooshang Nekounam Aliakbar 《Journal of Central South University》 SCIE EI CAS 2014年第6期2273-2281,共9页
Fault diagnostics is an important research area including different techniques.Principal component analysis(PCA)is a linear technique which has been widely used.For nonlinear processes,however,the nonlinear principal ... Fault diagnostics is an important research area including different techniques.Principal component analysis(PCA)is a linear technique which has been widely used.For nonlinear processes,however,the nonlinear principal component analysis(NLPCA)should be applied.In this work,NLPCA based on auto-associative neural network(AANN)was applied to model a chemical process using historical data.First,the residuals generated by the AANN were used for fault detection and then a reconstruction based approach called enhanced AANN(E-AANN)was presented to isolate and reconstruct the faulty sensor simultaneously.The proposed method was implemented on a continuous stirred tank heater(CSTH)and used to detect and isolate two types of faults(drift and offset)for a sensor.The results show that the proposed method can detect,isolate and reconstruct the occurred fault properly. 展开更多
关键词 fault diagnosis nonlinear principal component analysis auto-associative neural networks
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Opportunistic Relaying Schemes for Amplify and Forward Bidirectional Relay Channels with Multi antenna Sources 被引量:1
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作者 Wang Zibin Yuan Fu +2 位作者 Ding Hong Xiang Liangjun Zheng Linhua 《China Communications》 SCIE CSCD 2012年第4期71-79,共9页
We consider a two-way relay network where the Amplify-and-Forward (AF) protocol is adopted by all relays in this paper.The network consists of two multi-antenna source nodes and multiple distributed single-antenna rel... We consider a two-way relay network where the Amplify-and-Forward (AF) protocol is adopted by all relays in this paper.The network consists of two multi-antenna source nodes and multiple distributed single-antenna relays.Two opportunistic relaying schemes are proposed to efficiently utilize the antennas of the source nodes and the relay nodes.In the first scheme,the best relay is selected out by a max-min-max criterion before transmitting.After that,at each source,only the antenna with the largest channel gain between itself and the best relay is activated to transmit and receive signals with full power.In the second scheme,assisted by the best relay which is selected by the typical max-min criterion,both source nodes use all their antennas to exchange data,and match filter beamforming techniques are employed at both source nodes.Further analyses show that all schemes can achieve the full diversity order,and the conclusions are not only mathematically demonstrated but numerically illustrated.System performance comparisons are carried out by numerical methods in terms of rate sum and outage probability,respectively.The beamforming assisted scheme can be found to be superior to the antenna selection scheme when accurate Channel State Information (CSI) is available at the transmitters.Otherwise,the latter is very suitable. 展开更多
关键词 opportunistic relaying AMPLIFY-AND-FORWARD antenna selection BEAMFORMING two-way relay channels (TWRCs) MAX-MIN
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Research on Influence of Electromagnetic Interference on X-Ray Digital Detection
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作者 Guo Taotao Wang Dada +1 位作者 Guo Tieqiao Yu Hong 《Electricity》 2012年第5期38-43,共6页
X-ray digital imaging technology has found wide application owing to its advantages of real-time, visualization and rapid imaging. In substations the substantial electromagnetic interference has some influence on the ... X-ray digital imaging technology has found wide application owing to its advantages of real-time, visualization and rapid imaging. In substations the substantial electromagnetic interference has some influence on the live detection by the X-ray digital imaging technology, hindering the promotion of the technology in the detection of electric equipment. Based on a large number of field tests, the author carded out a series of researches on electromagnetic interference protection measures, image de-noising, and image enhancement algorithms. 展开更多
关键词 SUBSTATION live detection X-RAY digital imaging electromagnetic interference image de-noising image enhancement
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Primary Research of EIT Inverse Problem Based on CS (Compressed Sensing) Technique 被引量:1
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作者 CHANG Tiantian DAI Meng XU Canhua FU Feng YOU Fusheng DONG Xiuzhen 《Journal of Mathematics and System Science》 2013年第1期41-46,共6页
EIT (electrical impedance tomography) problem should be represented by a group of partial differential equation, in numerical calculation: the nonlinear problem should be linearization approximately, and then linea... EIT (electrical impedance tomography) problem should be represented by a group of partial differential equation, in numerical calculation: the nonlinear problem should be linearization approximately, and then linear equations set is obtained, so EIT image reconstruct problem should be considered as a classical ill-posed, ill-conditioned, linear inverse problem. Its biggest problem is the number of unknown is much more than the number of the equations, this result in the low imaging quality. Especially, it can not imaging in center area. For this problem, we induce the CS technique into EIT image reconstruction algorithm. The main contributions in this paper are: firstly, built up the relationship between CS and EIT definitely; secondly, sparse reconstruction is a critical step in CS, built up a general sparse regularization model based on EIT; finally, gives out some EIT imaging models based on sparse regularization method. For different scenarios, compared with traditional Tikhonov regularization (smooth regularization) method, sparse reconstruction method is not only better at anti-noise, and imaging in center area, but also faster and better resolution. 展开更多
关键词 Electrical impedance tomography compressed sensing inverse problem REGULARIZATION sparse reconstruction.
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Vertical Integration by Means of Profinet
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作者 Olga Ruban 《Journal of Energy and Power Engineering》 2012年第3期488-493,共6页
This paper discusses some aspects of interdisciplinary problems of industrial automation curriculum in Virumaa College of Tallinn University of Technology at engineering level. The problems being faced by engineers ar... This paper discusses some aspects of interdisciplinary problems of industrial automation curriculum in Virumaa College of Tallinn University of Technology at engineering level. The problems being faced by engineers are increasingly interdisciplinary and complicated because the development of new products and processes depends upon the integration of many different technologies. Expansion of possibilities of already existing fieldbus systems is carried out by means of integration them into Profinet (PROcess Field NET) communications. The lab set-model of vertical integration-for data gathering from smart Profibus PA sensor, data transmission, controllers configuration for Profinet IO direct interfacing of distributed field devices on the Ethernet is discussed in this paper. 展开更多
关键词 Wireless network vertical integration data transmission PROFINET DIAGNOSTICS site survey.
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A new technique for deriving the quiet day curve from imaging riometer data at Zhongshan Station, Antarctic 被引量:2
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作者 HE Fang HU HongQiao +1 位作者 HU ZeJun LIU RuiYuan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第10期1967-1976,共10页
A new technique for estimating quiet day curve(QDC)was suggested.To validate the new approach,QDCs were derived from data acquired by the imaging riometer installed at the Chinese Zhongshan Station in Antarctic.The ev... A new technique for estimating quiet day curve(QDC)was suggested.To validate the new approach,QDCs were derived from data acquired by the imaging riometer installed at the Chinese Zhongshan Station in Antarctic.The evaluation was performed by comparing the difference between QDC derived by the new technique and those derived by Tanaka’s technique.The results were discussed in terms of the diurnal variation and discrepancy.Also,cosmic noise absorption(CNA)images were built using both techniques in order to evaluate the implications of the changes when obtaining them using different methods of the QDC determination.The influence of the multiplicative factor value on the QDC determination in Tanaka’s technique was evaluated. 展开更多
关键词 riometer absorption technique
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