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Simulation research on scattering characteristics by complex targets

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Journal of Systems Engineering and Electronics 2007年第4期18卷 685-691页

作者： Guo Kunyi Sheng xinqing Center for Electromagnetic Simulation School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

A simulation approach based on a full-wave numerical method is presented to study electromagnetic characteristics by complex targets. How to validate simulation results is considered thoroughly under no analytical and measured data, where a double-check criterion is designed for our simulation approach. As an example, the scattering of F-117A is studied by using our simulation approach under all polarizations, different frequency bands, incident and scattering directions, etc., some of which, such as cross-polarization, bistatic RCS, have not been considered in the previous literature.

关键词： electromagnetic characteristics simulation complex targets hybrid FE-BI-MLFMA.

Novel high-performance element in the electromagnetic finite-element method——node-edge element

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Journal of Systems Engineering and Electronics 2008年第5期19卷 878-881页

作者： Sheng xinqing Peng Zhen Center for Electromagnetic Simulation School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

It is known in the computational electromagnetics （CEM） that the node element has a relative wellconditioned matrix, but suffers from the spurious solution problem; whereas the edge element has no spurious solutions, but usually produces an ill-conditioned matrix. Particularly, when the mesh is over dense, the iterative solution of the matrix equation from edge element converges very slowly. Based on the node element and edge element, a node-edge element is presented, which has no spurious solutions and better-conditioned matrix. Numerical experiments demonstrate that the proposed node-edge element is more efficient than now-widely used edge element.

关键词： node-edge element node element edge element matrix condition number.

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调节性T细胞在乳腺癌新辅助化疗中的意义

中华内分泌外科杂志 2016年第5期10卷 391-394页

作者：潘颖毛卫波付春燕郑琏叶新清陈述政浙江丽水市中心医院乳腺科丽水323000 浙江丽水市中心医院病理科丽水323000 广西医科大学附属肿瘤医院病理科南宁530021

目的探究调节性T细胞在乳腺癌新辅助化疗中的意义。方法本课题组采用免疫组化技术通过IPP软件检测了64例乳腺癌与癌旁组织中FoxP3与CCL20的表达，进一步结合患者的临床资料分析调节性T细胞与乳腺癌病理特征、化疗效果的相关性。结果通... 详细信息

目的探究调节性T细胞在乳腺癌新辅助化疗中的意义。方法本课题组采用免疫组化技术通过IPP软件检测了64例乳腺癌与癌旁组织中FoxP3与CCL20的表达，进一步结合患者的临床资料分析调节性T细胞与乳腺癌病理特征、化疗效果的相关性。结果通过运用DAB染色免疫组化技术在乳腺癌组织和癌旁组织中检测FoxP3因子和调节性T细胞的特异趋化因子CCL20，结果发现。癌组织FoxP3和CCL20相对光密度值分别为（26．09±6．22）％、（42．69±9．13）％，均显著高于癌旁组织中的（2．84±0．73）％、（6．17±0．99）％，差异均有统计学意义（P〈0．01）。通过X2检验提示，高表达调节性T细胞的癌组织中，肿瘤更大、临床分期偏恶性、淋巴结易转移、新辅助化疗效果差（P〈0．05）。结论调节性T细胞受趋化因子诱导在乳腺癌组织中大量聚集，进而影响乳腺癌发生发展与新辅助化疗的疗效。

关键词：调节性T细胞乳腺癌新辅助化疗免疫组化

Evidence of China's sea boundary in the South China Sea

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Acta Oceanologica Sinica 2017年第4期36卷 1-12页

作者： WANG Ying GE Chendong ZOU xinqing Collaborative Innovation Center of South China Sea Studies Nanjing University Nanjing 210023 China Ministry of Education Key Laboratory for Coast and Island Development Nanjing University Nanjing 210023 China

According to a series of important historical maps,i.e.,the Location Map of the South China Sea Islands,the Nansha Islands,Zhongsha Islands,Xisha Islands,Yongxing Island and Shidao Island,and Taiping Island（archived by the Territorial Administration Division of the Ministry of Interior of Republic of China in 1946）,and the Administration District Map of the Republic of China published in 1948,the dashed line surrounding the South China Sea Islands represents China＇s sea boundary in the South China Sea at that *** was both connected with,and an extension of,the land boundary of *** that time the dashed line was used to represent the waters boundaries while the solid line was used to represent the land boundary—a universal method used in maps that was then recognized *** above observation provides historical and scientific evidence of China＇s sea boundary in the South China Sea that is useful for the international maritime delimitation over the South China Sea area.

关键词： China's sea boundary historical maps maritime sovereignty South China Sea

Scattering center modeling for low-detectable targets

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Journal of Systems Engineering and Electronics 2022年第3期33卷 511-521页

作者： CHEN Yanxi GUO Kunyi XIAO Guangliang SHENG xinqing Institute of Radio Frequency Technology and Software School of Integrated Circuits and ElectronicsBeijing Institute of TechnologyBeijing 100081China

The scattering centers(SCs)of low-detectable targets(LDTs)have a low scattering *** is difficult to build the SC model of an LDT using the existing methods because these methods mainly concern dominant SCs with strong scattering *** paper presents an SC modeling approach to acquire the weak SCs of *** employ the induced currents at the LDT to search SCs,and the joint time-frequency transform together with the Hough transform to separate the scattering contributions of different *** swarm optimization(PSO)is applied to improve the estimation results of *** accuracy of the SC model built by this approach is verified by a full-wave numerical *** validation results show that the SC model of the LDT can precisely simulate the signatures of high-resolution images,such as high-resolution range profile and inverse synthetic aperture radar(ISAR)images.

关键词： low-detectable target(LDT) stealth target scattering center(SC)model time-frequency representation full-wave method

A review of control loop monitoring and diagnosis:Prospects of controller maintenance in big data era

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Chinese Journal of Chemical Engineering 2016年第8期24卷 952-962页

作者： xinqing Gao Fan Yang Chao Shang Dexian Huang Department of Automation Tsinghua University Tsinghua National Laboratory for Information Science and Technology

Owing to wide applications of automatic control systems in the process industries, the impacts of controller performance on industrial processes are becoming increasingly significant. Consequently, controller maintenance is critical to guarantee routine operations of industrial processes. The workflow of controller maintenance generally involves the following steps: monitor operating controller performance and detect performance degradation, diagnose probable root causes of control system malfunctions, and take specific actions to resolve associated problems. In this article, a comprehensive overview of the mainstream of control loop monitoring and diagnosis is provided, and some existing problems are also analyzed and discussed. From the viewpoint of synthesizing abundant information in the context of big data, some prospective ideas and promising methods are outlined to potentially solve problems in industrial applications.

关键词： Control loop performance assessment Industrial alarm system Process knowledge Root cause diagnosis Big data

Phase Equilibria in Nb-Si-Mo Ternary Alloys at 1273 K and 2073 K

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Chinese Journal of Aeronautics 2008年第5期21卷 448-454页

作者： Huang Qiang Ma Chaoli Zhao xinqing Xu Huibin School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Phase equilibrium in Nb-Si-Mo ternary alloys （〈37.5 at.% Si） at 1 273 K and 2 073 K is investigated by using X-ray diffraction （XRD） analysis, scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）. The partial isothermal section at 1 273 K, which contains four single-phase regions, five two-phase regions and two three-phase regions, is basically the same as that at 1 973 K. However, when the temperature increases to 2 073 K, the three-phase region of Nbss＋ct-（Nb（Mo））sSi3＋13-（Nb,Mo）sSi3 obviously moves towards the Nb-rich comer. This suggests that Nb-Si-Mo ternary alloys remain stable at least up to 1 973 K.

关键词： Nb/NbsSi3 in-situ composite isothermal section phase equilibria microstructure

Effect of Cr on Microstructure and Fracture Toughness of Nb-20Ti-16Si-xCr Alloys

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稀有金属材料与工程 2009年第A3期38卷 8-12页

作者： Tang Liang Ma Chaoli Zhao xinqing Beijing University of Aeronautics and Astronautics Beijing 100083 China

The present paper reported the phase stability and microstructures evolution of Nb-20Ti-16Si-xCr (x = 0～20at.%) in-situ composites as function of Cr addition. It was suggested that with the addition of Cr less than 7%, the silicide phase in as-cast Nb-20Ti-16Si alloy was Nb3Si. The silicides changed to be α-Nb5Si3 by the addition of Cr above 7%. It was found that annealing of 1300 ℃ for 100 h could result in the decomposition of Nb3Si to NbSS and α-Nb5Si3 in Cr containing Nb-20Ti-16Si based alloys by means of eutectoid reaction. Whereas in the case of alloy without Cr addition, the Nb3Si in Nb-20Ti-16Si alloy keep good stability during the high temperature annealing. The Cr additions larger than 5% in Nb-20Ti-16Si-xCr alloys could result in the formation of Cr-rich Laves phase. In addition, the influence of Cr addition on the room temperature fracture toughness of the alloys after annealing was reported.

关键词：微观结构铌硅化物韧性合金

Mineral Potential Mapping for Tungsten Polymetallic Deposits in the Nanling Metallogenic Belt, South China

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Journal of Earth Science 2014年第4期25卷 689-700页

作者： Yue Liu Qiuming Cheng Qinglin Xia xinqing Wang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Faculty of Earth Resources China University of Geosciences Department of Earth and Space Science and Engineering Department of Geography York UniversityToronto M3J1P3 Canada

The Nanling belt in South China has considerable resources of tungsten polymetallic commodities and is one of the most important metallogenic belts in the world. Data-driven weights-of-evidence （WofE） and fuzzy logic models are used to evaluate the tungsten polymetallic potential of the Nanling belt. Initially, seven ore-controlling factors derived from multi-source geospatial datasets （e.g., geological, geochemical, and geophysical） are used for data integration in the two models. Two mineral potential maps are generated that efficiently predicate the locations of the deposits. The WofE map predicate 81% of the deposits within 13.6% of the study area, whereas the fuzzy logic map predicate 81.5% of the deposits within 13% of the area. The predictive maps are syntheses of spatial association rules, which provide better understanding of those factors that control the distribution of mineralization and trigger eventual exploration work in new areas. Subsequently, in order to evaluate the success rate accuracy, the receiver operating characteristic curves and area under the curves （AUCs） for the two potential maps are constructed. The results show that the AUCs for the WofE and fuzzy logic models are 0.775 7 and 0.840 6, respectively. The higher AUC value for the fuzzy logic model implies that it delineate a greater number of favorable areas compared with the WorE model. Overall, the capabilities of both models for correctly classifying areas with existing mineral deposits are satisfactory.

关键词： weights-of-evidence fuzzy logic data integration mineral potential assessment receiver operating characteristic (ROC) curve.