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Near-field 3D imaging approach combining MJSR and FGG-NUFFT

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1096-1109页

作者： WANG Shuzhen FANG Yang ZHANG jin’gang LUO Mingshi LI Qing School of Computer Science and Technology Xidian UniversityXi’an 710071China School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China College of Materials Sciences and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China College of Computer Science Xi’an Shiyou UniversityXi’an 710065China The Fourth Research Institute of Telecommunications Technology Co. LtdXi’an 710061China

A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of the compressed sensing(CS)theory and the matched filtering(MF)*** approach has the advantages of high precision and high efficiency:multichannel joint sparse constraint is adopted to improve the problem that the images recovered by the single channel imaging algorithms do not necessarily share the same positions of the scattering centers;the CS dictionary is constructed by combining MF and FGG-NUFFT,so as to improve the imaging efficiency and memory ***,a near-field 3 D imaging model of joint sparse recovery is constructed by combining the MF-based imaging ***,FGG-NUFFT and reverse FGG-NUFFT are used to replace the interpolation and Fourier transform in MF-based imaging methods,and a sensing matrix with high precision and high efficiency is constructed according to the traditional imaging ***,a fast imaging recovery is performed by using the improved separable surrogate functionals(SSF)optimization algorithm,only with matrix and vector ***,a 3 D imagery of the near-field target is obtained by using both the horizontal and the pitching interferometric phase *** paper contains two imaging models,the only difference is the sub-aperture method used in inverse synthetic aperture radar(ISAR)*** to traditional CS-based imaging methods,the proposed method includes both forward transform and inverse transform in each iteration,which improves the quality of *** experimental results show that,the proposed method improves the imaging accuracy by about O(10),accelerates the imaging speed by five times and reduces the memory usage by about O(10~2).

关键词： interference imaging joint sparse recovery compressed sensing(CS) matching filtering(MF) fast Gaussian gridding nonuniform fast Fourier transform(NUFFT) near-field 3D imaging

Two-level hierarchical feature learning for image classification

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 897-906页

作者： Guang-hui SONG Xiao-gang jin Gen-lang CHEN Yan NIE College of Computer Science and Technology Zhejiang University Ningbo Institute of Technology Zhejiang University College of Science and Technology Ningbo University

In some image classification tasks, similarities among different categories are different and the samples are usually misclassified as highly similar categories. To distinguish highly similar categories, more specific features are required so that the classifier can improve the classification performance. In this paper, we propose a novel two-level hierarchical feature learning framework based on the deep convolutional neural network(CNN), which is simple and effective. First, the deep feature extractors of different levels are trained using the transfer learning method that fine-tunes the pre-trained deep CNN model toward the new target dataset. Second, the general feature extracted from all the categories and the specific feature extracted from highly similar categories are fused into a feature vector. Then the final feature representation is fed into a linear classifier. Finally, experiments using the Caltech-256, Oxford Flower-102, and Tasmania Coral Point Count(CPC) datasets demonstrate that the expression ability of the deep features resulting from two-level hierarchical feature learning is powerful. Our proposed method effectively increases the classification accuracy in comparison with flat multiple classification methods.

关键词： Transfer learning Feature learning Deep convolutional neural network Hierarchical classification Spectral clustering

Synthesis of Hydroxypropyl-β-cyclodextrin Bonded Silica-gel and its Application to Resolution

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Chinese Chemical Letters 2006年第12期17卷 1547-1550页

作者： jin gang YU Ke Long HUANG Du Shu HUANG jin Yue PU Institute of Functional Material and Chemistry College of Chemistry and Chemical Engineering Central South University Changsha 410083

In order to set up a simple and effective method for resolution of optical isomers, hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolution of clenbuterol and propranolol were investigated on these thin-layer chromatography plates using different combinations of solvent systems at ambient temperature. The best simultaneous resolution was achieved in solvent system of acetonitrilen-butanol （50：50, v/v）. Rst values of resolution of clenbuterol hydrochloride and propranolol hydrochloride are 3.6 and 4.3, respectively. The spots of different enantiomers are separated clearly. The results showed that hydroxypropyl-β-cyclodextrin bonded silica-gel could be successful in resolution of chiral adrenergic drugs. The study offers a direct, rapid and reliable method for separation of this kind of optically active compounds.

关键词： Hydroxypropyl-β-cyclodextrin bonded silica gel synthesis resolution chiral enantiomers.

Pragmaticization and the L2 Acquisition of Chinese Ba Constructions

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世界汉语教学 1993年第2期7卷 150-157页

作者： Hong gang jin Hamilton College

1. Syntacticization Vs Pragmaticization Syntacticization is a phenomenon which in-volves the typological interactions between topicprominent (Tp) and subject prominent (Sp) lan-guages. From the perspective of language evolu-tion, syntacticization, as claimed by Givon(1979), is a process of tightening up syntax, inwhich constructions formerly organized to maxi-mize pragmatic functions become *** example, word order becomes more rigid;

关键词：汉语教学世界

Inhibition of Metalloproteinase Activity by Chinese Formulations Used to Treat Inflammatory Diseases

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Chemical Research in Chinese Universities 2006年第2期22卷 245-247页

作者： jin Feng-hai WANG Hui-ling ZHAO Shu-hua YANG jin-gang FANG Xue-xun Key Laboratory of Molecular Enzymology and Engineering the Ministry of Education Jilin University Changchun 130021 P. R. China School of Pharmacy Jilin University Changchun 130021 P. R. China College of Life Science Jilin University Changchun 130021 P. R. China The China-Japan Union Hospital Jilin University Changchun 130021 P. R. China

Matrix metalloproteinases （MMPs） are known to be involved in a number of pathological processes including cancer, atherosclerosis, arthritis and neurodegenerative disease among others. The drive to develop MMP inhibitors as therapeutics has been put forward for years by pharmaceutical companies as well as academicians. In an attempt to screen for MMP inhibitors from Traditional Chinese Medicines （TCMs） , a number of Chinese formulations used to treat inflammatory diseases such as nephritis and hepatitis have been studied. Strong inhibitory effects of three Chinese formulations toward the activity of MMP-16 have been discovered. These results suggest that these anti-inflammatory medicines contain some unknown MMP inhibitory compound（s） and provide reasonable molecular mechanisms for their theraoeutic effects.

关键词： Matrix metalloproteinase (MMP) Matrix metalloproteinase inhibitor ( MMPI ) Traditional Chinese Medicine(TCM) Herbal formulation

Low-power and area-optimized VLSI implementation of AES coprocessor for Zigbee system

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 89-94页

作者： LI Zhen-rong ZHUANG Yi-qi ZHANG Chao jin gang Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices Xidian University Xi'an 710071 China

A low-power and low-cost advanced encryption standard （AES） coprocessor is proposed for Zigbee system-on-a-chip （SoC） design. The cost and power consumption of the proposed AES coprocessor are reduced considerably by optimizing the architectures of SubBytes/InvSubBytes and MixColumns/InvMixColumns, integrating the encryption and decryption procedures together by the method of resource sharing, and using the hierarchical power management strategy based on finite state machine （FSM） and clock gating （CG） technologies. Based on SMIC 0.18 μm complementary metal oxide semiconductor （CMOS） technology, the scale of the AES coprocessor is only about 10.5 kgate, the corresponding power consumption is 69.1 μW/MHz, and the throughput is 32 Mb/s, which is reasonable and sufficient for Zigbee system. Compared with other designs, the proposed architecture consumes less power and fewer hardware resources, which is conducive to the Zigbee system and other portable devices.

关键词： Zigbee AES architecture encryption decryption application specific integrated circuit (ASIC)

Stability analysis for variable spindle speed milling with helix angle using an improved semi-discretization method

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Science China Technological Sciences 2013年第3期56卷 648-655页

作者： XIE QiZhi ZHANG QiChang WANG Wei jin gang HAN JianXin School of Mechanical Engineering Tianjin University Tianjin Key Laboratory of Nonlinear Dynamics and Chaos Control State Key Laboratory of Engines Tianjin University

Chatter in milling is still a main obstacle in surface finish,machining accuracy and tool *** prediction and avoidance are challenging subjects in the machining *** this paper,an improved semi-discretization method is proposed to predict variable spindle speed milling with helix *** on tool geometry and machining theory,the cutting region is divided into five different cases to calculate the cutting *** influences of radial immersion rate and modulation parameters relative to variable spindle speed milling are *** comparison with constant spindle speed,the simulation results show that the variable spindle speed scheme can obtain a larger range of *** short,the helix angle and variable spindle speed play an important role in the stability of milling process.

关键词： milling chatter semi-discretization helix angle variable spindle speed

Strategic games on a hierarchical network model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 271-278页

作者： Yi-xiao LI Xiao-gang jin Fan-sheng KONG Hui-lan LUO Institute of Artificial Intelligence Zhejiang University Hangzhou 310027 China Ningbo Institute of Technology Zhejiang University Ningbo 315100 China

Among complex network models,the hierarchical network model is the one most close to such real networks as world trade web,metabolic network,WWW,actor network,and so *** has not only the property of power-law degree distribution,but also the scaling clustering coefficient property which Barabási-Albert(BA)model does not *** model is a model of network growth based on growth and preferential attachment,showing the scale-free degree distribution *** this paper,we study the evolution of cooperation on a hierarchical network model,adopting the prisoner's dilemma(PD)game and snowdrift game(SG)as metaphors of the interplay between connected *** model provides a unifying framework for the emergence of *** interestingly,we found that on hierarchical model,there is no sign of cooperation for PD game,while the fre-quency of cooperation decreases as the common benefit decreases for *** comparing the scaling clustering coefficient prop-erties of the hierarchical network model with that of BA model,we found that the former amplifies the effect of *** different performances of PD game and SG on complex network,we also found that common benefit leads to cooperation in the *** our study may shed light on the emergence of cooperation in both natural and social environments.

关键词： Complex network Hierarchical network model Barabási-Albert (BA) model Prisoner's dilemma (PD) game Snowdrift game (SG)

Downregulation of AQP2 and AQP2 mRNA expression in kidney medulla of rats with bile duct ligation

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Hepatobiliary & Pancreatic Diseases International 2007年第6期6卷 636-640页

作者： Wang, Yong Liu, jin-gang Han, Ji-Long China Med Univ Shengjing Hosp Affiliated Hosp 2 Dept Hepatobiliary Shenyang 110004 Peoples R China

BACKGROUND: Obstructive jaundice is a common disease. Acute renal injury, secondary to obstructive jaundice, is one of the main causes of postoperative multiple system failure. This investigation evaluated renal function and renal aquaporin 2 (AQP2) expression changes in obstructive jaundice. METHODS: Forty male Wistar rats were equally randomized into two groups. Twenty in the obstructive jaundice group were subjected to common bile duct ligation, and then were subdivided into 7- and 14-day obstruction groups, and the other 20 sham-operated rats were also subdivided into 7- and 14-day groups. At the end of each experiment, rats were sacrificed, venous blood was collected from the inferior vena cava, and serum creatinine and urine nitrogen concentrations were measured. At the same time, the medulla of the right kidney was separated and AQP2 expression was assessed. The RT-PCR technique was used to detect AQP2 mRNA expression. RESULTS: Ligation of the common bile duct caused significant rises in serum bilirubin, creatinine clearance and urine nitrogen. AQP2 expression in the medulla decreased mere significantly (38.35 +/- 2.08) in the 7-day ligation group than in the sham-operated group (41.06 +/- 1.04), as did that in the 14-day ligation group, even more than (31.89 +/- 1.57). The expression of AQP2 mRNA also decreased more significantly in the 14-day group (0.5429 +/- 0.1107) than in the 7-day group (0.6071 +/- 0.1328). CONCLUSION: AQP2 expression is inhibited in obstructive jaundice, and so is its gene expression.

关键词： aquaporin 2 obstructive jaundice kidney medulla