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Robust radar automatic target recognition algorithm based on HRRP signature

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Frontiers of Electrical and Electronic Engineering in China 2012年第1期7卷 49-55页

作者： Hongwei LIU Feng CHEN Lan DU zheng bao National Laboratory of Radar Signal Processing Xidian UniversityXi'an 710071China

Automatic target recognition （ATR） is an important function for modern radar. High resolution range profile （HRRP） of target contains target struc- ture signatures, such as target size, scatterer distribu- tion, etc, which is a promising signature for ATR. Sta- tistical modeling of target HRRPs is the key stage for HRRP statistical recognition, including model selection and parameter estimation. For statistical recognition al- gorithms, it is generally assumed that the test samples follow the same distribution model as that of the train- ing data. Since the signal-to-noise ratio （SNR） of the received HRRP is a function of target distance, the as- sumption may be not met in practice. In this paper, we present a robust method for HRRP statistical recogni- tion when SNR of test HRRP is lower than that of train- ing samples. The noise is assumed independent Gaus- sian distributed, while HRRP is modeled by probabilistic principal component analysis （PPCA） model. Simulated experiments based on measured data show the effective- ness of the proposed method.

关键词： radar target recognition high resolution range profile (HRRP) probabilistic principal component analysis (PPCA)

Practical and concise synthesis of 2-oxo-3,4,5,6-tetraethoxyazepane from D-glucono-1,5-lactone

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Chinese Chemical Letters 2008年第7期19卷 795-796页

作者： Yan Jiao Zhi Jie Fang Yu Hua Jiang bao Hui zheng Jie Cheng School of Chemical Engineering Nanjing University of Science ＆ Technology Nanjing 210094 China

2-Oxo-3R,4S,5S,6S-tetraethoxyazepane was conveniently synthesized from D-glucono-1, 5-1actone with a yield of 10% overall. The key step of synthetic route-reductive 1,6-cyclization was completed efficiently by using P... 详细信息

关键词： Azepane Ph3P Reduction Iminosugars Glucono lactone

Expression and significance of intratumoral interleukin-12 and interleukin-18 in human gastric carcinoma

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World Journal of Gastroenterology 2007年第11期13卷 1747-1751页

作者： zheng-bao Ye Tao Ma Hao Li Xiao-Long Jin Hai-Min Xu Division of Gastrointestinal Oncology Ruijin Hospital Affiliated to School of Medicine Shanghai Jiaotong University. Shanghai 200030. China Department of Pathology Ruijin Hospital Affiliated to School of Medicine Shanghai Jiaotong University Shanghai 200030 China

AIM: To explore the effect of intratumoral expressions of interleukin-12 (IL-12) and interleukin-18 (IL-18) on clinical features, angiogenesis and prognosis of gastric carcinoma. METHODS: The expressions of IL-12 and IL-18 from 50 samples of gastric cancer tissue were analyzed by immunohistochemistry, and microvessel density (MVD) was determined with microscopic imaging analysis system. RESULTS: The positive expression rates of IL-12 and IL-18 were 44% (22/50) and 26% (13/50), respectively. IL-12 was significantly associated with pathologic differentiation, depth of invasion, lymph node metastasis, distant metastasis, and TNM stage, and IL-18 was closely related to distant metastasis. Intratumoral IL-12 and IL-18 expressions were not statistically related to MVD scoring. IL-12-positive patients survived significantly longer than those with IL-12-negative tumors, but there was no significant difference between IL-18-positive patients and IL-18-negative ones. The multivariate analysis with Cox proportional hazard model revealed IL-12, MVD and T stage were independent prognostic factors. CONCLUSION: The positive expressions of IL-12 and IL-18 can play an important role in progression and metastasis of gastric cancer, and IL-12 might be an independent factor of poor prognosis in gastric carcinoma.

关键词： Interleukin-12, Interleukin-18 Antitumor immunity Gastric cancinoma Prognosis

DBS imaging and GMTI in a wideband airborne mechanic scanning radar

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Frontiers of Electrical and Electronic Engineering in China 2006年第4期1卷 410-415页

作者： LI Yan-ping XING Meng-dao bao zheng Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

A principle for choosing the coherent integration number and an improved Doppler beam sharpening(DBS)imaging algorithm for mechanic scanning radar are pre-sented in this *** compensating the range migration in wideband airborne mechanic scanning radar,the proposed DBS imaging algorithm can efficiently improve the resolu-tion of a DBS *** addition,based on the characteristic that the echo from the moving target will be modulated by the antenna pattern,a novel method used to locate the mov-ing target is also presented,which begins with the sub-aperture moving target detection followed by the sliding window *** location can be achieved by using this ***,the results on real radar data are pro-vided to demonstrate the effectiveness of these proposed methods.

关键词： DBS range migration correction moving target indication moving targets location radar imaging

Effects of Chromium Addition on Preparation and Properties of Bulk Cementite

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Journal of Iron and Steel Research International 2016年第8期23卷 842-850页

作者： bao-chao zheng Zhi-fu HUANG Jian-dong XING Yi-yang XIAO Xiao FAN Yong WANG State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong University

Bulk cementites with the Cr contents of 0,3.01,6.03,8.22,and 11.51mass% were prepared by mechanical alloying（MA）and spark plasma sintering（SPS）.The results indicated that when the Cr content was low（3.01mass%）,the phases were composed of cementite with a small amount ofα-Fe at a sintering temperature of 1 173 K,but the microstructure became single-phase alloyed cementite as the Cr content was further *** showed that microaddition of Cr was beneficial for promoting the formation of ***,the mechanical performance of cementite can be greatly affected by the variation of Cr *** hardness,elastic modulus and elastic recovery presented a remarkably increasing tendency with the addition of Cr,and the maximum micro-hardness and elastic modulus values reached 1 070.74 HV and 199.32 GPa,respectively,which were similar to the precipitation phase（cementite）obtained by melting and casting ***,when the Cr content was below 11.51mass%,the crystal structure of Fe3C-type cementite would not change with increasing the Cr content.A Cr atom replaced an Fe atom in the lattice of the cementite,and voids appeared when Cr was doped into the cementite at content of about11.51mass%,causing the relative density to decrease.

关键词： modulus sintering spark hardness alloyed melting remarkably replaced alloying amorphous

High-speed ground moving target detection research using triangular modulation FMCW

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Frontiers of Electrical and Electronic Engineering in China 2009年第2期4卷 127-133页

作者： Yi LIANG Long ZHANG Mengdao XING zheng bao National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China Xi’an Polytechnic University Xi’an 710048China

The frequency modulated continuous wave(FMCW)radar has the characteristics of low probability of interception,good hidden property and the ability to counter anti-radiation *** paper proposes a new method for high-speed ground moving target detection(GMTD)using triangular modulation *** to the characteristic of the opposite range shift induced by the upslope and downslope modulation FMCW,the upslope and downslope are imaged,*** compensation of continuous motion of the platform and time difference between upslope and downslope signals for imaging,the moving target can be detected through displaced phase center antenna(DPCA)*** the moving target is detected,the moving target image is extracted,and correlation processing is used to obtain the range shift,which can be used to estimate the target radial velocity,and further to find the real position of the *** effectiveness of this method is verified by the result of computer simulation.

关键词： ground moving target detection(GMTD) triangular modulation frequency modulated continuous wave(FMCW) correlation processing

Ghost Imaging Using Orbital Angular Momentum

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Chinese Physics Letters 2011年第12期28卷 153-156页

作者： ZHAO Sheng-Mei DING Jian DONG Xiao-Liang zheng bao-Yu Institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003

We present a novel encoding scheme in a ghost-imaging system using orbital angular *** the signal arm,object spatial information is encoded as a phase *** an N−grey-scale object,different phase matrices,varying from 0 toπwith incrementπ/N,are used for different greyscales,and then they are modulated to a signal beam by a spatial light *** to the conservation of the orbital angular momentum in the ghost imaging system,these changes will give different coincidence rates in measurement,and hence the object information can be extracted in the idler *** simulations and experiments,the results show that our scheme can improve the resolution of the image *** with another encoding method using orbital angular momentum,our scheme has a better performance for both characters and the image object.

关键词： ghost Ghost scheme

Scalable and Privacy-Preserving Data Sharing Based on Blockchain

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Journal of Computer Science & Technology 2018年第3期33卷 557-567页

作者： bao-Kun zheng Lie-Huang Zhu Meng Shen Feng Gao Chuan Zhang Yan-Dong Li Jing Yang School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China School of Information Management for Law China University of Political Science and Law Beijing 102249 China

With the development of network technology and cloud computing, data sharing is becoming increasingly popular, and many scholars have conducted in-depth research to promote its flourish. As the scale of data sharing expands, its privacy protection has become a hot issue in research. Moreover, in data sharing, the data is usually maintained in multiple parties, which brings new challenges to protect the privacy of these multi-party data. In this paper, we propose a trusted data sharing scheme using blockchain. We use blockchain to prevent the shared data from being tampered, and use the Paillier cryptosystem to realize the confidentiality of the shared data. In the proposed scheme, the shared data can be traded, and the transaction information is protected by using the （p, t）-threshold Paillier cryptosystem. We conduct experiments in cloud storage scenarios and the experimental results demonstrate the efficiency and effectiveness of the proposed scheme.

关键词： data sharing privacy-preserving cloud computing blockchain Paillier cryptosystem

Addison's disease caused by adrenal tuberculosis may lead to misdiagnosis of major depressive disorder: A case report

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World Journal of Clinical Cases 2024年第1期12卷 217-223页

作者： Tian-Xiang Zhang Hong-Yan Xu Wei Ma Jian-bao zheng Department of Tuberculosis The Tuberculosis Hospital of Shaanxi ProvinceXi’an 710100Shaanxi ProvinceChina Department of General Surgery First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Addison’s disease(AD)is a rare but potentially fatal disease in Western countries,which can easily be misdiagnosed at an early *** adrenal tuberculosis(TB)may lead to depression in *** SUMMARY We report a case of primary adrenal insufficiency secondary to adrenal TB with TB in the lungs and skin in a 48-year-old *** patient was misdiagnosed with depression because of her depressed *** had hyperpigmentation of the skin,nails,mouth,and *** final diagnosis was adrenal TB that resulted in the insufficient secretion of adrenocortical *** hormone test,skin biopsy,T cell spot test of TB,and adrenal computed tomography scan were used to confirm the *** patient’s condition improved after hormone replacement therapy and TB *** Given the current status of TB in high-burden countries,outpatient doctors should be aware of and pay attention to TB and understand the early symptoms of AD.

关键词： Primary adrenal insufficiency Adrenal tuberculosis Fatigue Hypotension Hyperkalemia Hyponatremia Depression Case report