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Near field 3-D imaging approach for joint high-resolution imaging and phase error correction

Journal of Systems Engineering and Electronics 2017年第2期28卷 199-211页

作者： Yang Fang Baoping wang Chao Sun Zuxun Song shuzhen wang School of Electronics and Information Northwestern Polytechnical University Xi’an 710072 China National Key Laboratory of Science and Technology on UAV Xi’an 710065 China School of Computer Science and Technology Xidian University Xi’an 710071 China

This paper combines compressed sensing (CS) imaging theory and range migration algorithm (RMA), and then proposes a near-field three-dimensional (3-D) imaging approach for joint high-resolution imaging and phase error correction. Firstly, a sparse measurement matrix construction method based on a logistic sequence is proposed, which conducts nonlinear transformation for the determined logistic sequence, making it obey uniform distribution, then conducts sign function mapping, and generates the pseudorandom sequence with Bernoulli distribution, thus leading to good signal recovery under down-sampling and easy availability for engineering realization. Secondly, in combination with the RMA imaging approach, the dictionary with all scene information and phase error correction is constructed for CS signal recovery and error correction. Finally, the non-quadratic solution model jointing imaging and phase error correction based on regularization is built, and it is solved by two steps - the separable surrogate functionals (SSF) iterative shrinkage algorithm is adopted to realize target scattering estimate; the iteration mode is adopted for the correction of the dictionary model, so as to achieve the goal of error correction and highly-focused imaging. The proposed approach proves to be effective through numerical simulation and real measurement in anechoic chamber. The results show that, the proposed approach can realize high-resolution imaging in the case of less data; the designed measurement matrix has better non-coherence and easy availability for engineering realization. The proposed approach can effectively correct the phase error, and achieve highly-focused target image. © 2017 Beijing Institute of Aerospace Information.

关键词： Compressed sensing Error correction Image reconstruction Iterative methods Linear transformations Mathematical transformations Signal reconstruction Signal sampling

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A Directional Differential-Fed UWB Antenna with Stable Radiation Pattern

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第6期33卷 -页

作者： Fang Yang wang Baoping Sun Chao Song Zuxun wang shuzhen School of Electronics and Information Northwestern Polytechnical University Science and Technology on UAV Laboratory Northwestern Polytechnical University School of Computer Science and Technology Xidian University

A directional ultra-wideband(UWB)antenna with improved radiation patterns is *** proposed sheme comprises a differential-fed microstrip antenna and a rectangular *** hexagon-shaped slot and four triangle-cut corners on the ground plane of the planar antenna are used to improve the impedance matching within the UWB frequency range.A rectangular cavity is used as the reflector for the planar microstrip antenna,so as to achieve directed *** measured results indicate that the designed antenna exhibits a stable broadside directional radiation patterns within the entire operating frequency ***,thanks to the differentially driven technique,the cross-polarization is greatly decreased and the polarization purity is maintained in a high level.

关键词： differential-fed ultra wide band microstrip antenna

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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

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海藻糖脂肪酸二酯的酶法合成及性质

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食品科学 2021年第24期42卷 149-158页

作者：汪淑珍暨南大学食品科学与工程系广东广州510632

采用固定化脂肪酶Novozym 435催化选择性合成6,6’-O-海藻糖脂肪酸二酯。在叔丁醇-吡啶(11∶9,V/V)混合溶剂中,通过海藻糖和不同碳链长度(C_(6)~C_(18))的脂肪酸乙烯酯发生酯交换反应实现,海藻糖和脂肪酸乙烯酯物质的量比为1∶4。通过... 详细信息

采用固定化脂肪酶Novozym 435催化选择性合成6,6’-O-海藻糖脂肪酸二酯。在叔丁醇-吡啶(11∶9,V/V)混合溶剂中,通过海藻糖和不同碳链长度(C_(6)~C_(18))的脂肪酸乙烯酯发生酯交换反应实现,海藻糖和脂肪酸乙烯酯物质的量比为1∶4。通过核磁共振波谱及质谱分析对产物进行结构鉴定,分析产物的亲水亲油平衡(hydrophilic lipophilic balance,HLB)值、发泡性能和热稳定性,同时用噻唑蓝法分析该系列海藻糖脂肪酸二酯的细胞毒性。结果表明:结构鉴定其为海藻糖脂肪酸二酯,产物得率为43%~75%;海藻糖癸酸二酯和海藻糖月桂酸二酯具有较好的发泡性能(起泡性分别为101.00%和142.67%,泡沫稳定性(80 min内)分别为40%~60%和50%~70%),海藻糖油酸二酯热稳定性最佳(温度达到350℃时剩余质量仍为60.58%);细胞毒性结果表明海藻糖油酸二酯安全、低毒。研究结果为开发食品领域高附加值的新型糖酯类非离子型表面活性剂提供了新方向。

关键词：固定化脂肪酶酯交换反应发泡性热稳定性细胞毒性

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Health promoting activities and corresponding mechanism of(–)-epicatechin-3-gallate

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Food Science and Human Wellness 2022年第3期11卷 568-578页

作者： Zhiliang Li Changchun Feng Hongjin Dong Weibin Jin Wenying Zhang Jianfeng Zhan shuzhen wang College of Life Science Huanggang Normal UniversityHubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive UtilizationHubei Collaborative Innovation Center for the Characteristic Resources Exploitation of Dabie MountainsHubei Zhongke Research Institute of Industrial TechnologyHuanggang 438000China College of Agriculture Yangtze UniversityJingzhou 434000China

(–)-Epicatechin-3-gallate(ECG),a bioactive polyphenolic compound,has contributed a lot to the health benefits of green *** attention has been focused on(–)-epigallocatechin-3-gallate(EGCG),but limited research has been performed towards *** EGCG,ECG also possesses various pharmacological and physiological properties,such as mediation of antioxidant activities,anti-inflammation response,regulation of cell proliferation and apoptosis,as well as anticancer properties during angiogenesis,invasion and metastasis *** ECG has various molecular targets within the cells,including CYP enzymes,phaseⅡdetoxification and antioxidant enzymes,as well as pro-inflammatory *** antineoplastic mechanism contains inhibition of phase 1 CYP enzymes,induction of phaseⅡdetoxification and antioxidant enzymes,high anti-inflammatory efficacy,arrest of cell cycle progression,regulation of apoptosis,as well as mediation of metastasis *** particular,the gallate moiety of ECG is critical for mediating inhibitory effects towards cancer *** regulation of intracellular signaling pathways,ECG also inhibits RNase A and matrix metalloproteinase enzymatic activity via chelating metals(copper and zinc)in cancer *** review has summarized recent studies on pharmacological properties of ECG,and discussed corresponding mechanism on modulation of cellular signaling events by ECG,hoping to broaden its multiple usage.

关键词： (-)-Epicatechin-3-gallate Polyphenolic compounds Pharmacological properties Anticarcinogenic agent Natural antioxidants Antimicrobial properties

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Multifunctional health-promoting effects of oolong tea and its products

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Food Science and Human Wellness 2022年第3期11卷 512-523页

作者： shuzhen wang Ting Zeng Shuang Zhao Yu Zhu Changchun Feng Jianfeng Zhan Shiming Li Chi-Tang Ho Alexander Gosslau Huanggang Normal University College of Life ScienceHubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive UtilizationHubei Collaborative Innovation Center for the Characteristic Resources Exploitation of Dabie MountainsHubei Zhongke Research Institute of Industrial TechnologyHuanggang 438000China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China Department of Food Science Rutgers UniversityNJ 08901USA Department of Science(Biology) City University of New YorkNY 10007USA

Oolong tea,partially fermented from Camellia sinensis leaves,exhibits significant antioxidative,anti-inflammatory,and anti-cancer activities as indicated in several in vitro and in vivo ***,studies on health promoting effects of oolong tea and its characteristic compounds are *** potential efficacy of bioactives derived from oolong tea and their roles as promising anticancer agents,their cardio-protective benefits during hypoxic conditions,effects in treating allergic disorders,potential prebiotic activities,improvement of blood lipid status in human beings,effectivity as oral hypoglycemic agent in the treatment of type 2 diabetes,and their potentials to reduce the risk of obesity have been discussed in this *** promising studies mainly gained from animal studies might broaden the consumption and usage of the phenolic-enriched oolong tea and its products in food and pharmaceutical ***,potential health beneficial effects of oolong tea in humans should be further complemented by large-sized,randomized double-blind and placebo-controlled trials to consolidate potential therapeutic applications.

关键词： Oolong tea Anticancer potential Antioxidative activity Microbiota modulating activities Synergistic effects

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On the Social Attributes of Internal Control

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学术界 2016年第1期 317-321页

作者： wang shuzhen Yu Jun Department of Management Hefei University

With the development of social economy,the social attributes of internal control are also developed in it's historical evolution,this paper discusses the connotation of social attributes embodied in the internal control objectives,and the core content of the social attributes contained in the internal control elements,and finally points out the limitations of internal control is good agent to promote the social attributes.

关键词： internal control objective components social attributes

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Construction of Guiding System for Growth and Development of College Students under the Student-oriented Concept

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Asian Agricultural Research 2018年第5期10卷 89-91页

作者： shuzhen wang Qing TANG College of Information Engineering Northwest A&F University Department of Physical Education Northwest A&F University

The student-oriented concept is a kind of people orientation. It emphasizes respect and support for students. It is student-centered,and is for all students. At the school level,the guiding principles of student orientation and respecting teachers and teaching must be adhered to,and corresponding reforms in the school's system,policies and environment needs to be carried out. At the university teacher level,the concept of student orientation must be adhered to in teaching,and it is regarded as the guiding concept of teaching and education and is implemented in classroom teaching and practical teaching. At the level of college administrator,the concept of student orientation must be adhered in the course of daily management and service to do better management,service and education work. In order to better implement the student-oriented concept and promote the growth and development of college students,we needs to build a mentor team for college students' growth based on political workers,establish a team of academic tutors for college students based on professional teachers and build a platform for cooperation between schools and enterprises. The innovative training mode can promote students to grow into talents.

关键词： Student-oriented concept College students Growth Construction

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Dynamic Changes of Antibodies to SARS-CoV-2 in COVID-19 Patients at Early Stage of Outbreak

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Virologica Sinica 2020年第6期35卷 744-751页

作者： Huaqing Shu shuzhen wang Shunan Ruan Yaxin wang Jiancheng Zhang Yin Yuan Hong Liu Yongran Wu Ruiting Li Shangwen Pan Yaqi Ouyang Shiying Yuan Peng Zhou You Shang Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Institute of Anesthesiology and Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Jin-Yin-Tan Hospital Wuhan 430023China CAS Key Laboratory of Special Pathogens Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China

The coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has spread around the world with high *** diagnose promptly and accurately is the vital step to effectively control its *** characteristics of SARSCoV-2-specific antibodies which are important for diagnosis of infection have not been fully *** this retrospective,single-center,observational study,we enrolled the initial 131 confirmed cases of COVID-19 at Jin-Yin-Tan Hospital who had at least one-time antibody tested during their *** dynamic changes of IgM and IgG antibodies to SARS-CoV-2 nucleocapsid protein in 226 serum samples were detected by *** sensitivities of IgM and IgG ELISA detection were *** showed that the sensitivity of the IgG ELISA detection(92.5%)was significantly higher than that of the IgM(70.8%)(P\0.001).The meantimes of seroconversion for IgM and IgG were6 days and 3 days,*** IgM and IgG antibody levels peaked at around 18 days and 23 days,and then IgM fell to below the baseline level at about day 36,whereas IgG maintained at a relatively high *** conclusion,antibodies should be detected to aid in diagnosis of COVID-19 *** could be a sensitive indicator for retrospective diagnosis and contact tracing,while IgM could be an indicator of early infection.

关键词： Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) Coronavirus Antibody Serology

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用带有平滑约束的CLEAN算法恢复日像仪图像

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中国机械工程 2006年第7期17卷 666-669页

作者：王书振西安电子科技大学西安710071

为了解决CLEAN算法处理展源时存在的迭代抖动、收敛不稳定的弊端,借鉴最大熵算法的平滑约束概念,通过修正CLEAN算法迭代过程中的脏束,提出了带有平滑约束的CLEAN算法。通过对国家天文台拟建日像仪图像恢复仿真,验证了该改进算法在图像... 详细信息

为了解决CLEAN算法处理展源时存在的迭代抖动、收敛不稳定的弊端,借鉴最大熵算法的平滑约束概念,通过修正CLEAN算法迭代过程中的脏束,提出了带有平滑约束的CLEAN算法。通过对国家天文台拟建日像仪图像恢复仿真,验证了该改进算法在图像恢复质量和分辨率两个方面的性能均较CLEAN算法有所提高。

关键词：日像仪 CLEAN算法反卷积图像恢复

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