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Remote Monitoring and Diagnosis System for High-speed Wire Rolling Mills

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武汉理工大学学报 2006年第S2期28卷 612-616页

作者： CUI Lingli ZHANG Jianyu DING Fang GAO Lixin WANG Dapeng (College of Mechanical Engineering and Applied Electronics technology,beijing University of technology,advanced Manufacturing technology,The key laboratory of beijing Municipality,beijing 100022,china College of Mechanical Engineering and Applied Electronics technology Beijing University of TechnologyAdvanced ManufacturingTechnologyThe Key Laboratory of Beijing MunicipalityBeijing 100022China

Traditional fault diagnosis systems of rolling mills mostly use single machine monitoring net,which leads the re- al-time data running only in the enterprise locally and can not monitor and manage the high-speed wire rolling mills between units, workshops and factories concentratedly.A new-type structure of remote diagnosis system for high-speed wire rolling mills is pre- sented in this *** signal processing,computer network and remote diagnosis etc techniques are used to predictive maintenance manage the rolling mills units in this *** new structure reinforced the remote feedback function,made up the existing fault diagnosis systems’ insufficiency in the extension and the function,promoted resource sharing and avoided the repeat develop- *** remote diagnosis example shows that the system can monitor and diagnose the fault information of remote machine timely and effectively.

关键词： rolling mills fault diagnosis remote monitoring remote diagnosis

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Dynamic call and connection admission control in automatically switched optical network for grid computing applications

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science china(information sciences) 2012年第2期55卷 419-432页

作者： LIU Lei,GUO HongXiang,HONG XiaoBin,WU Jian & LIN JinTong key laboratory of information Photonics and Optical Communications,Ministry of Education,beijing University of Posts and Telecommunications,beijing 100876,china 1. key laboratory of information Photonics and Optical Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In recent years,Grid computing applications are becoming more and more important to the scientific and business communities and are likely to open to the consumer market and widely develop in the near future,which is a great challenge brought by the potentially large number of Grid users(perhaps millions)and high frequency of their job *** switched optical network(ASON),which is a promising high capacity intelligent transport network infrastructure,has been already deployed in the world and regarded as a promising solution to foster the expansion of Grid computing from local area networks to wide area ***,by theoretical analysis and simulative evaluation of Grid job blocking in the distributed call and connection setup process of ASON,this paper verifies that ASON and the conventional admission control mechanism confront a problem in supporting future large-scale Grid *** order to address this issue,a novel dynamic call and connection admission control(DCCAC)scheme is proposed to improve the network performance and guarantee quality of service(QoS)of Grid *** scheme is applicable with complete network information,no network information and partial network *** results show that the DCCAC scheme can improve the efficiency of the network to a great ***,all the analysis and algorithms in this paper are based on ITU-T ASON recommendations,which make the DCCAC scheme more applicable in network engineering for future Grid computing.

关键词： automatically switched optical network(ASON) Grid computing blocking probability call admission control connection admission control

Multi-layer network architecture in support of end-to-end transparent optical connectivities

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science china(information sciences) 2011年第3期54卷 674-682页

作者： GUO HongXiang , WU Jian, HONG Xiao Bin & LIN Jin Tong key laboratory of information Photonics and Optical Communications, Ministry of Education, beijing University of Posts and Telecommunications, beijing 100876, china 1. key laboratory of information Photonics and Optical Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In order to effectively accommodate a wide variety of emerging and future applications with diverse requirements, an intelligent optical network capable of the rapid and resilient delivery of on-demand transparent transmission capacity is required. This paper investigates a multi-layer network architecture where a generalized multiple protocol label switching (GMPLS) controlled transparent wavelength switched optical network (WSON), as the transport core, collaborates with multiple client optical burst switching (OBS) networks distributed at the edge. Dynamic interworking mechanism as well as the related signaling/routing protocol ex- tensions for multi-QoS burst streams transmission among different OBS domains are proposed so as to provision an end-to-end (e2e) transparent optical connectivity with on-demand bandwidth to end-users. Moreover, the survivability of this transparent optical connectivity is also addressed. To validate the feasibility of this architecture, an integrated OBS/WSON network testbed was constructed, and stable e2e transparent connectivities were successfully demonstrated for an efficient multi-QoS burst streams transmission.

关键词： multi-layer network transparent optical network OBS WSON GMPLS

A novel endorectal RF coil for high resolution MRI and spectroscopy of the prostate

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Progress in Natural science:Materials International 2005年第5期15卷 472-476页

作者： ZHANG Hongjie 1,2, SONG Xiaoyu1, WANG Xiaoying3, XU Pingfang1 and BAO Shanglian1*(1. beijing key laboratory of Medical Physics & Engineering, Peking University, beijing 100871, china 2. Navy General Hospital, beijing 100037, china 3. Peking University First Hospital, beijing 100034, china) beijing key laboratory of Medical Physics & Engineering Peking University Beijing 100871 China Navy General Hospital Beijing 100037 China Peking University First Hospital Beijing 100034 China

The diagnosis of prostate diseases by magnetic resonance imaging (MRI) in vivo is sometimes difficult for the lower signal to noise ratio (SNR). To increase the SNR of the prostate image, we designed a RF coil that can be inserted into rectum and was named endorectal coil. The properties of RF coil were evaluated using a network analyzer. Moreover the images and spectroscopy of a special phantom were acquired and the results were compared to those of the commercial TORSO coil (G.E. Medical Systems, USA). Our coil gave a significantly higher SNR at the region of interest (ROI). The achieved high local SNR and resulting high spatial resolution would add more anatomic and biochemical information to the diagnosis of prostate diseases.

关键词： MRI RF coil endorectal coil.

Efficient DPCA SAR imaging with fast iterative spectrum reconstruction method

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science china(information sciences) 2012年第8期55卷 1838-1851页

作者： FANG Jian1,ZENG JinShan1,XU ZongBen1&ZHAO Yao2 1M inistry of Education key Lab for Intelligent networks and network Security Xi'an Jiaotong University,Xi'an 710049,china 2N ational key laboratory of science and technology on Microwave Imaging&Institute of Electronics,Chinese Academy of sciences,beijing 10004.,china 1. Ministry of Education key Lab for Intelligent networks and network Security Xi’an Jiaotong University Xi’an 710049 China2. National Key Laboratory of Science and Technology on Microwave Imaging & Institute of Electronics Chinese Academy of Sciences Beijing 100049 China

The displaced phase center antenna(DPCA)technique is an effective strategy to achieve wide-swath synthetic aperture radar(SAR)imaging with high azimuth ***,traditionally,it requires strict limitation of the pulse repetition frequency(PRF)to avoid non-uniform ***,any deviation could bring serious ambiguity if the data are directly processed using a matched *** break this limitation,a recently proposed spectrum reconstruction method is capable of recovering the true spectrum from the nonuniform ***,the performance is sensitive to the selection of the *** regularization based imaging may provide a way to overcome this *** existing time-domain method,however,requires a large-scale observation matrix to be built,which brings a high computational *** this paper,we propose a frequency domain method,called the iterative spectrum reconstruction method,through integration of the sparse regularization technique with spectrum analysis of the DPCA *** approximately expressing the observation in the frequency domain,which is realized via a series of decoupled linear operations,the method performs SAR imaging which is then not directly based on the observation matrix,which reduces the computational cost from O(N2)to O(N log N)(where N is the number of range cells),and is therefore more efficient than the time domain *** sparse regularization scheme,realized via a fast thresholding iteration,has been adopted in this method,which brings the robustness of the imaging process to the PRF *** provide a series of simulations and ground based experiments to demonstrate the high efficiency and robustness of the *** simulations show that the new method is almost as fast as the traditional mono-channel algorithm,and works well almost independently of the PRF ***,the suggested method can be accepted as a practical and efficient wide-swath SAR imaging technique.

关键词： displaced phase center antenna sparse regularization iterative thresholding spectrum reconstruction

On degrees of freedom of the cellular network

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science china(information sciences) 2010年第05期53卷 1034-1043页

作者： SUN Jun 1,2 , LIU YingZhuang 1,2 & ZHU GuangXi 1,2 1 Department of Electronics and information Engineering, Huazhong University of science and technology, Wuhan 430074, china 2 Division of Optical network and Intelligent Communication, Wuhan National laboratory for Optoelectronics, Wuhan 430074, china 1. Department of Electronics and information Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of Optical Network and Intelligent Communication Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (e.g., base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of interference alignment, we are able to exactly characterize the sum degrees of freedom (DoF) of the network when the channel coefficients are timeor frequency-varying, which equals KM K+min(M,K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there also exists the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprising result.

关键词： capacity degrees of freedom cellular network interference alignment interference channel MIMO

A novel adaptive spectrum forming filter:Application in cognitive ultra-wideband

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science china(information sciences) 2010年第12期53卷 2584-2599页

作者： LI Bin ,ZHOU Zheng & ZOU WeiXia key Lab of Universal Wireless Communications,MOE.Wireless network Lab,beijing University of Posts and Telecommunications,beijing 100876,china 1. key Lab of Universal Wireless Communications MOE. Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

Ultra wideband impulse radio(UWB-IR) has important applications in high data rate communications,high precision positioning and penetrating target *** with cognitive radio(CR),UWB can also greatly alleviate the current spectrum ***,the existing UWB waveforms are faced with two *** spectrum utilization of UWB signal is rather low,which reduces the communication ***,it appears difficult for UWB-IR to avoid spectrum collision with other incumbent *** UWB will inevitably interfere other legal wireless *** by these considerations,we model the UWB waveform design into an interpolation *** on radial basis function neural network,a novel UWB pulse is presented in this *** UWB pulse is then realized though reasonable simplification on the already proposed theoretical *** designed UWB pulses can adaptively track the external spectral environment where UWB devices work and reconfigure its emission spectrum according to the state of primer users without any modification on *** frequency utilization is maximized when there is no active primary *** adequate spectrum avoidance has also been achieved without much spectrum utilization degradation within the non-primary *** and analysis show that our UWB-IR pulse is much superior to the other existing UWB signals in the frequency utilization,spectrum avoidance and in the transmission performance.

关键词： UWB-IR cognitive radio pulse design RBF network spectrum efficiency spectrum avoidance

Software structure evaluation based on the interaction and encapsulation of methods

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science china(information sciences) 2012年第12期55卷 2816-2825页

作者： ZHENG QingHua 1,2,OU ZhiJiang 1,2,LIU Ting 1,YANG ZiJiang 3,HOU YuQiao 1,2 & ZHENG Chao 1,2 1 MOE key laboratory for Intelligent networks and network Security,Xi'an Jiaotong University,Xian 710049,china 2 Shaanxi key laboratory of Satellite-terrestrial network technology R&D,Xi'an Jiaotong University,Xian 710049,china 3 Department of Computer science,Western Michigan University,Michigan,USA 1. MOE key laboratory for Intelligent networks and network Security Xi’an Jiaotong University Xian 710049 China2. Shaanxi Key Laboratory of Satellite-terrestrial Network Technology R&D Xi’an Jiaotong University Xian 710049 China3. Department of Computer Science Western Michigan University Michigan USA

Software structure is the most important factor affecting the quality of a *** evaluation of software structure is a foundational technique for software ***,the traditional evaluation criteria,such as "high cohesion and low coupling",are no longer appropriate for the new web applications,which are designed with a hierarchical framework.A novel approach is proposed in this paper to evaluate software quality based on the interaction and encapsulation of *** particular,two criteria for high quality software,the functional and hierarchical structure,are proposed to support widely used web *** cohesion and coupling and layer matching ratios between methods within a software package are calculated to determine whether the package is well implemented in terms of functional or hierarchical *** approach enables us to quantify the quality of a software system according to the structural types of its *** were carried out on 18 versions of Struts and six open-source software *** evaluation concurs with the intuition that minor upgrades,aimed at fixing bugs and adding minor functionality quickly,reduce software quality,whereas major upgrades,which normally clean up messy code and re-construct the software,improve software quality.

关键词： software structure evaluation method interaction method encapsulation functional structure hierarchical structure

Nonlinear optical properties and superluminal propagation in the ruby

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Chinese science Bulletin 2010年第6期55卷 473-477页

作者： GAO Feng1,2,3,XU JingJun1,2,3,ZHANG GuoQuan1,2,3 & ZHANG WenDing1,2,3 1 Photonics Center,College of Physics science,Nankai University,Tianjin 300457,china 2 The key laboratory of advanced Technique and Fabrication for Weak-Light Nonlinear Photonics Materials of Ministry of Education,Nankai University,Tianjin 300457,china 3 Tianjin key laboratory of Photonics Materials and technology for information science,Nankai University,Tianjin 300457,china Photonics Center College of Physics Science Nankai University Tianjin 300457 China key laboratory of advanced Technique and Fabrication for Weak-Light Nonlinear Photonics Materials of Ministry of Education Nankai University Tianjin 300457 China Tianjin key laboratory of Photonics Materials and technology for information science Nankai University Tianjin 300457 China

In this review article,we summarized the study of the weak light nonlinear properties associated with group velocity change in the *** ruby could be reduced to a two-level system,in which population oscillations could lead to a subluminal *** the modulated TEM00 beam introduced into the ruby,self-phase modulation together with Fraunhofer diffractions and nondegenerate two-wave coupling between different spatial frequency components of the beam occurs at the same *** oscillations,self-phase modulation together with Fraunhofer diffractions and nondegenerate two-wave coupling mechanism competes with each other,which brings a new phenomenon of self-superluminal group velocity propagation in the ruby.

关键词：非线性光学性质超光速传播红宝石自相位调制 TEM00模速度变化光束耦合空间频率

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