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Journal of Systems engineering and Electronics 2010年第3期21卷 397-403页

作者： Weijian Si,Xicai Si,and Zhiyu Qu college of Information and Communication engineering,Harbin engineering University,Harbin 150001,p.r.china college of Information and Communication engineering Harbin Engineering UniversityHarbin 150001P.R.China

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（prS） to antagonize non-coherent radar *** the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is *** this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated *** this new method,prS can distinguish radar and non-coherent decoy with good *** the simulation result and the experimental data confirm the performance of the method.

关键词： radar countermeasures passive radar seeker(prS) non-coherent decoy direction of arrival(DOA) estimation.

Optimal Approach to SAr Image Despeckling

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Journal of Systems engineering and Electronics 2002年第1期13卷 48-52页

作者： Zheng Zonggui & Mao Shiyi Department of Electronic engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083,p.r.china Department of Electronic engineering Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China

Speckle filtering of synthetic aperture radar (SAr) images while preserving the spatial signal variability (texture and fine structures) still remains a challenge. Many algorithms have been proposed for the SAr imagery despeckling. However, simulated annealing (SA) methods is one of excellent choices currently. A critical problem in the study on SA is to provide appropriate cooling schedules that ensure fast convergence to near-optimal solutions. This paper gives a new necessary and sufficient condition for the cooling schedule so that the algorithm state converges in all probability to the set of global minimum cost states. Moreover, it constructs an appropriate objective function for SAr image despeckling. An experimental result of the actual SAr image processing is obtained.

关键词： Convergence of numerical methods Cooling Image processing Scheduling Simulated annealing

An Ontology-Based Information retrieval Model for Vegetables E-Commerce

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Journal of Integrative Agriculture 2012年第5期11卷 800-807页

作者： TAO Teng-yang ZHAO Ming college of Information and Electrical engineering China Agricultural UniversityBeijing 100083P.R.China

With the rapid increment of the information on the web, traditional information retrieval based on the keywords is far from user＇s satisfaction in recall and precision. In order to improve the recall ratio and the precision radio of Ir engine in the vegetables e-commerce, an information retrieval model based on the vegetables e-commerce ontology is presented in this paper, vegetables e-commerce ontology was constructed by gathering and the analyzing vegetables e-commerce domain information on the web. The vegetables e-commerce ontology is composed of some kinds of vegetable classes and hierarchy relationship of vegetables classes. In the process of information retrieval, domain ontology helps to index information and information inference. An ontology-based information retrieval model is implemented, and which has more functions than the keyword-based web information retrieval engines. The experiment results show that the recall ratio and the precision ratio of ontology-based information retrieval model are higher than that of the information retrieval engine based on keyword at a certain extent.

关键词： domain-ontology vegetables e-commerce information retrieval

Decisive influence of the ionization strength of cosmic rays on the cavitation characteristics of pure water

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Science china(Technological Sciences) 2009年第6期52卷 1804-1808页

作者： CHANG JinShi college of Water Conservancy & Civil engineering,china Agricultural University,Beijing 100083,china college of Water Conservancy & Civil engineering China Agricultural University Beijing 100083 China

The experiment result in this article shows that the initial and critical cavitation pressure of pure water are both increasing along with the increase of height above sea level,and the ionization strength of cosmic rays in the lower aerosphere is the crucial factor which influences the cavitation pressure of pure *** author concludes the relationship between the cavitaion pressure of pure water and the height above sea ***,air particles in water caused by the radiation of cosmic rays can exist in the water for a long time and will not escape.

关键词： initial cavitaiton pressure critical cavitation pressure ionization strength of cosmic rays height above sea level

Indeterminacy Causal Inductive Automatic reasoning Mechanism Based on Fuzzy State Description

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Journal of Systems engineering and Electronics 2002年第2期13卷 64-70页

作者： Yang Bingru & Tang JingDept. of Computer Science and engineering, University of Science and Technology, Beijing 100083, p.r.china(received May 23, 2001) Dept. of Computer Science and engineering University of Science and Technology Beijing 100083 P. R. China

A framework of knowledge representation of fuzzy language field and fuzzy language value structure is shown. Then the generalized cell automation that can synthetically process fuzzy indeterminacy and random indeterminacy and generalized inductive logic causal model are put forward. On this basis, the logic indeterminacy causal inductive automatic reasoning mechanism which is based on fuzzy state description is presented. At the end of this paper its application in the development of intelligent controller is discussed.

关键词： Control systems Fuzzy sets

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu Zhengzhou University of Information engineering,Zhengzhou 450002,p.r.china Zhengzhou University of Information engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum

Community-based prevention and treatment of cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第3期21卷 315-322页

作者： Sheng-Shou HU The Writing Committee of the report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascular health in *** is the third section of the report with a specific focus on community-based prevention and treatment of cardiovascular diseases(CVD).This section of the report underscores the importance of initiatives outlined in the"Healthy china 2030 plan,"emphasizing the comprehensive prevention and control strategy for chronic diseases.A key aspect of this plan involves the establishment of national demonstration areas aimed at comprehensive prevention and control of chronic *** 2020,488 such areas had been set up across china,surpassing the initial target and covering a significant proportion of counties and *** report highlights the successful implementation of these strategies in Lishan district,Anshan city,where demonstration areas for comprehensive prevention and control of chronic diseases were launched in *** the course of seven years,the number of healthy units increased substantially,leading to improvements in managing risk factors for CVD among *** reductions in prevalence rates of overweight,obesity,smoking,passive smoking,and drinking were observed,along with the development of healthier behaviors among ***,Qiaokou district in Wuhan City,designated as a national demonstration area in 2014,implemented comprehensive public health promotion ***,special clinics for hypertension intervention were established,contributing to an increase in self-reported rates of hypertension,a slight decrease in prevalence,and a remarkable improvement in the control rate among treated ***,these efforts underscore the effectiveness of community-based approaches in driving positive health outcomes and advancing the comprehensive prevention and control of chronic diseases,particularly cardiovascular diseases,in china.

关键词： prevention district treatment

Cardiovascular risk Factors in china

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Journal of Geriatric Cardiology 2024年第2期21卷 153-199页

作者： Sheng-Shou HU the Writing Committee of the report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual report on Cardiovascular Health and Diseases in china(2022) intricate landscape of cardiovascular health in china. This section dissects cardiovascular risk factors in china which including hypertension, dyslipidemia, diabetes mellitus, chronic kidney disease, metabolic syndrome and air pollution. Hypertension prevalence has steadily increased in china,with efforts to control it facing challenges in achieving optimal rates, especially in rural areas. Interventions like salt substitutes and intensive blood pressure control show promise but need improvement. Abnormal lipid levels, indicative of dyslipidemia,have risen significantly, posing a risk for cardiovascular diseases. Despite efforts, many patients struggle to achieve target lipid levels, necessitating improved treatment strategies. Both type 1 and type 2 diabetes mellitus affect millions of adults in china,with long-term complications adding to the disease burden. Early intervention and effective management are crucial to mitigate its impact. prevalent among older adults, chronic kidney disease is associated with diabetes mellitus, hypertension, and cardiovascular diseases, necessitating comprehensive management approaches. The prevalence of metabolic syndrome, characterized by a cluster of risk factors, has increased in both adults and adolescents, calling for lifestyle modifications and public health interventions. Ambient and household air pollution remain significant environmental risk factors, despite some improvements in air quality. Continued efforts to reduce emissions are essential for mitigating associated health risks. Addressing these risk factors requires a multifaceted approach, including public health initiatives, policy interventions, and individual-level strategies to promote healthy lifestyles and reduce environmental exposures. Surveillance and research efforts are crucial for monitoring trends and developing effective strategies to lessen the burden of cardiovascular diseases in

关键词： landscape adding spite

LINEAr ACTIVE STrUCTUrES AND MODES (Ⅱ) —DISCrETE SYSTEMS AND BEAMS

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Applied Mathematics and Mechanics(English Edition) 2004年第8期25卷 854-862页

作者：王永刚龚靖School of Civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 p.r.china Department of Civil engineering Northeast china Institute of Electric power Jilin 132012 p.r.china 张景绘School of Civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 p.r.china School of Civil engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.ChinaSchool of Science Chang'an University Xi'an 710064 P.R.China

The basic concepts about the active structures and some attributes of the modes were presented in paper “Liner Active Structures and Modes]( I) ". The characteristics of the active discrete systems and active beams were discussed, especially, the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-storeyed building with sensors and actuators. The concept of the adjoint active structure was extended from the discrete systems to the beams that were the representations of the continuous structures. Two types of beams with different placements of the measuring and actuating systems were discussed in detail. One is the beam with the discrete sensors and actuators, and the other is the beam with distributed sensor and actuator function. The orthogonality conditions were derived with the modal shapes of the active beam and its adjoint active beam. An example shows that the variation of eigenvalues with feedback amplitude for the homo-configuration and non-homo-configuration active structures.

关键词： I) ". The characteristics of the active discrete systems and active beams were discussed especially the stability of the active structures and the orthogonality of the eigenvectors. The notes about modes were portrayed by a model of a seven-s