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High speed residue number system comparison for the moduli set {2^n-1, 2^n, 2^n+}
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作者 Ehsan Gholami Reza Farshidi +1 位作者 Mehdi Hosseinzadeh Keivan Navi 《通讯和计算机(中英文版)》 2009年第3期40-46,共7页
关键词 残余数字系统 二进制转换器 比拟 信号检测
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Comparisons and Assessment of Forest Fire Danger Systems 被引量:1
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作者 TianXiao-rui DouglasJMcrae +4 位作者 DenBoychu JinJi-zhong GaoCheng-da ShuLi-fu WangMing-yu 《Forestry Studies in China》 CAS 2005年第1期53-61,共9页
The paper gives a brief description about the current main forest fire danger rating systems in the world, which in- clude forest fire danger rating system used in Canada, USA, Australia, and other countries. It show... The paper gives a brief description about the current main forest fire danger rating systems in the world, which in- clude forest fire danger rating system used in Canada, USA, Australia, and other countries. It shows the composition, structure and development of the main fire danger rating systems. The limitations of those systems are also discussed. Through a comparison of the three main forest fire danger rating systems the paper describes their differences on development, fuel complex descriptions, inputs and outputs, and their applications and finds that the technologies of the Canadian forest fire danger rating system can be adopted for China to develop a national forest fire danger rating system. Two steps are needed to develop our own national forest fire danger rating system. Firstly, we apply the CFFDRS directly. Then some studies should be done to calibrate the FDRS to local weather and fuel characteristics. 展开更多
关键词 fire danger rating system comparison ASSESSMENT
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Comparison and Enlightenment of China's and EU's Food Safety Supervision Systems
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作者 Yanyu DENG Xing WU 《Asian Agricultural Research》 2019年第4期4-10,共7页
Food is the paramount necessity of the people,and safety is most essential for food. Food safety is related to people's fundamental interests,affecting people's basic health. It is an important factor in promo... Food is the paramount necessity of the people,and safety is most essential for food. Food safety is related to people's fundamental interests,affecting people's basic health. It is an important factor in promoting people's livelihood development and social progress. Compared with European countries and the United States in developed food safety supervision systems,the development of food safety supervision system in China is still relatively backward. As food safety supervision is not in place,food safety incidents have occurred in recent years,so that public's panic about food safety has intensified. It has a strong impact on social stability and the food economy. Thus,strengthening the construction of food safety supervision system is imperative. Since experiencing a series of food safety incidents,the EU has gradually improved its food safety supervision system and has developed the most comprehensive and mature food safety supervision system in the world. On the basis of sorting out the characteristics of EU's food safety supervision system,the development direction of China's food safety supervision system is proposed from four aspects: supervisor,legal system,law enforcement ability and safety standards. 展开更多
关键词 FOOD safety SUPERVISION system comparison ENLIGHTENMENT
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Digital Twins and Cyber Physical Systems toward Smart Manufacturing and Industry 4.0:Correlation and Comparison 被引量:117
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作者 Fei Tao Qinglin Qi +1 位作者 Lihui Wang A.Y.C.Nee 《Engineering》 SCIE EI 2019年第4期653-661,共9页
State-of-the-art technologies such as the Internet of Things(IoT),cloud computing(CC),big data analytics(BDA),and artificial intelligence(AI)have greatly stimulated the development of smart manufacturing.An important ... State-of-the-art technologies such as the Internet of Things(IoT),cloud computing(CC),big data analytics(BDA),and artificial intelligence(AI)have greatly stimulated the development of smart manufacturing.An important prerequisite for smart manufacturing is cyber-physical integration,which is increasingly being embraced by manufacturers.As the preferred means of such integration,cyber-physical systems(CPS)and digital twins(DTs)have gained extensive attention from researchers and practitioners in industry.With feedback loops in which physical processes affect cyber parts and vice versa,CPS and DTs can endow manufacturing systems with greater efficiency,resilience,and intelligence.CPS and DTs share the same essential concepts of an intensive cyber-physical connection,real-time interaction,organization integration,and in-depth collaboration.However,CPS and DTs are not identical from many perspectives,including their origin,development,engineering practices,cyber-physical mapping,and core elements.In order to highlight the differences and correlation between them,this paper reviews and analyzes CPS and DTs from multiple perspectives. 展开更多
关键词 Cyber–physical systems(CPS) Digital twin(DT) SMART MANUFACTURING CORRELATION and comparison
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A Comparison of GaN VS GaAs System Performance
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作者 Michael Schefter Mehdi Ardavan 《Aerospace China》 2018年第3期17-22,共6页
Traditionally RF power amplifiers used Gallium Arsenide(GaAs) technology which has a well behaved and understood performance. Over the past few years Gallium Nitride(GaN) technology is replacing GaAs because GaN is mo... Traditionally RF power amplifiers used Gallium Arsenide(GaAs) technology which has a well behaved and understood performance. Over the past few years Gallium Nitride(GaN) technology is replacing GaAs because GaN is more efficient and has a higher power density resulting in higher power MMICs and FETs.Subject to system link budgets, we usually want to run a given amplifier as close to saturation as possible to minimize CAPEX costs. Running an amplifier closer to saturation causes many non-linear effects that can cause link performance degradation and interfere with other users.To better understand and quantify the differences between GaN and GaAs amplifiers and the impact of this on system performance, some amplifier and system measurements will be taken. The findings will be documented in a white paper. 展开更多
关键词 GAN system GAAS system PERFORMANCE comparison
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Evaluation on Effectiveness of a New System as well as Analysis on Optimal Horizontal Eye Position for Vertical Video Head Impulse Test
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作者 Tao JIANG Fei LI +5 位作者 Jing YU Ruo-nan HUANG Rui GAO Chen-yong SHANG Jian-hua ZHUANG Wen-yan LI 《Current Medical Science》 2021年第4期705-711,共7页
Objective To compare the performances among three different systems for video head impulse test(vHIT),and to identify an optimal target angle for precisely evaluating the function of vertical semicircular canals in vH... Objective To compare the performances among three different systems for video head impulse test(vHIT),and to identify an optimal target angle for precisely evaluating the function of vertical semicircular canals in vHIT.Methods A two-center prospective study was done.Participants were sit 1.2 m away from the wall in a noise-proved room that dedicated for vHIT experiments.During the comparison experiments,similar settings were ensured in both hospitals,with the same distance to wall and angle of staring.For each equipment,the procedures followed the developers’recommendations.The same examiner performed the comparison between two systems in one location.For the eye-position projects,targets were placed on the wall sequentially at the pre-marked lines for different angles.For the comparison projects,9 and 13 participants were recruited,respectively.Any participant with otologic or vestibular disorders was excluded.A total of 26 healthy participants were recruited in the eye-position experiments,16 of which were further involved in inter-examiner tests.Results Our evaluations of three different systems showed that a new vHIT system,VertiGoggles®ZT-VNG-I(VG)performed as good as the long-tested Otometrics®ICS impulse(Oto)and EyeSeeCam®(ESC).During the comparison,we validated 25-degree,instead of right ahead at 0 degree,is a better place to set the targets when torsion was applied at vertical semicircular canal planes.Conclusion The new VG system is good for clinical practices.Furthermore,we proposed a new protocol to set the targets 25 degrees from right ahead after tilting head 45 degrees to evaluate vertical canals during vHIT. 展开更多
关键词 video head impulse test target angle vestibular disorder system comparison GOGGLES
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基于深度学习检索网络的医疗图像病例比对系统设计
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作者 王鑫 《电子设计工程》 2026年第1期155-158,164,共5页
为提升医疗图像检索的准确性和效率,研究融合深度残差网络和哈希学习算法,提出了一种基于深度哈希检索的医疗图像病例比对系统。测试结果表明,所提算法在脑部计算机断层扫描数据集上的准确率、召回率和平均精度均值分别为0.961、0.951、... 为提升医疗图像检索的准确性和效率,研究融合深度残差网络和哈希学习算法,提出了一种基于深度哈希检索的医疗图像病例比对系统。测试结果表明,所提算法在脑部计算机断层扫描数据集上的准确率、召回率和平均精度均值分别为0.961、0.951、0.925;在胃部计算机断层扫描数据集上的准确率、召回率和平均精度均值分别为0.973、0.953和0.945。综上所述,所提方法具有较高的图像检索效率和精度,反馈信息较为丰富,在提高医疗质量、推动医疗创新方面具有重要价值。 展开更多
关键词 深度学习 哈希算法 图像检索 病例分析 比对系统
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A CLASS OF NONLOCAL BOUNDARY VALUE PROBLEMS OF NONLINEAR ELLIPTIC SYSTEMS IN UNBOUNDED DOMAINS 被引量:64
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作者 莫嘉琪 欧阳成 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期93-97,共5页
The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems ar... The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem comparison theorem
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Impulsive control of chaotic systems and its applications in synchronization 被引量:3
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作者 吴波 刘洋 卢剑权 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期184-190,共7页
In this paper, some novel sufficient conditions for asymptotic stability of impulsive control systems are presented by comparison systems. The results are used to obtain the conditions under which the chaotic systems ... In this paper, some novel sufficient conditions for asymptotic stability of impulsive control systems are presented by comparison systems. The results are used to obtain the conditions under which the chaotic systems can be asymptotically controlled to the origin via impulsive control. Compared with some existing results, our results are more relaxed in the sense that the Lyapunov function is required to be nonincreasing only along a subsequence of switchings. Moreover, a larger upper bound of impulsive intervals for stabilization and synchronization is obtained. 展开更多
关键词 comparison systems impulsive control chaotic systems SYNCHRONIZATION
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THE SINGULARLY PERTURBED NONLINEARELLIPTIC SYSTEMS IN A HALF SPACE 被引量:2
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作者 张汉林 莫嘉琪 《数学物理学报(A辑)》 CSCD 北大核心 1997年第S1期195-199,共5页
The singularly perturbed problems for elliptic systems in a half space are con- sidered. Under suitable conditions, and by using the comparison theorem the existence and asymptotic behavior of solution for the boundar... The singularly perturbed problems for elliptic systems in a half space are con- sidered. Under suitable conditions, and by using the comparison theorem the existence and asymptotic behavior of solution for the boundary value problems are studied. 展开更多
关键词 ELLIPTIC system. SINGULAR perturbation. comparison THEOREM
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Impulsive control of stochastic system under the sense of stochastic asymptotical stability 被引量:3
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作者 牛玉俊 马戈 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期207-211,共5页
This paper studies the stochastic asymptotical stability of stochastic impulsive differential equations, and establishes a comparison theory to ensure the trivial solution's stochastic asymptotical stability. From th... This paper studies the stochastic asymptotical stability of stochastic impulsive differential equations, and establishes a comparison theory to ensure the trivial solution's stochastic asymptotical stability. From the comparison theory, it can find out whether the stochastic impulsive differential system is stable just by studying the stability of a deterministic comparison system. As a general application of this theory, it controls the chaos of stochastic Lii system using impulsive control method, and numerical simulations are employed to verify the feasibility of this method. 展开更多
关键词 stochastic impulsive system stochastic asymptotical stability comparison theory impulsive control
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Analysis onto Competence-oriented Engineering Education System:A Perspective into the Differences between Chinese and German Engineering Education
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作者 Xin Zhang Ying Zhang Hua Li 《计算机教育》 2018年第12期91-97,共7页
Through engineering education, a set of didactical programs and activities are planned to bring the essential knowledge, expertise and training to the students from the corresponding discipline and make them gain the ... Through engineering education, a set of didactical programs and activities are planned to bring the essential knowledge, expertise and training to the students from the corresponding discipline and make them gain the competence of coping with various professional problems independently. Although holding the same views on the importance of developing competence, China and Germany construct the respective education systems in consideration of the different circumstances. In this paper, we propose the analysis onto the engineering education systems in the two countries and characterize the systems as competence-oriented. Through reflecting the differences, we mainly propose three suggestions as the theoretical contribution for deriving advantages from the German engineering education system. 展开更多
关键词 competence-oriented PRINCIPLES of TRAINING STUDENTS EDUCATION system comparison
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Intelligence Comparison between Fish and Robot Using Chaos and Random
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作者 Mamoru Minami Akira Yanou Jun Hirao 《通讯和计算机(中英文版)》 2012年第9期1025-1037,共13页
关键词 机器人视觉 随机运动 情报 混沌 运动模式 智能方法 反馈系统
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A Class of Singularly Perturbed Nonlinear Elliptic Systems
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作者 莫嘉琪 《应用数学》 CSCD 1997年第2期110-114,共5页
A class of singularly perturbed dlliptic systems are condidered. Under suitable conditions,uaing the comparison theorem the asymptotic behavior of solution for the boundary value problemare studied.
关键词 非线性 椭圆系统 奇异扰动
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408UL和System Four(AC)两种采集系统在塔里木探区的应用对比
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作者 王凡 郭延伟 +2 位作者 王胜利 齐志刚 杨华平 《物探装备》 2008年第4期238-243,共6页
408UL、SystemFour这两种采集系统是目前比较常用的仪器,408UL主机以SOLARIS操作系统为软件平台,应用软件可实时监控排列,尤其在多台爆炸机生产、震源施工时,方便对采集质量进行控制,其主机硬件和野外地面设备轻便,不足之处是操作系统... 408UL、SystemFour这两种采集系统是目前比较常用的仪器,408UL主机以SOLARIS操作系统为软件平台,应用软件可实时监控排列,尤其在多台爆炸机生产、震源施工时,方便对采集质量进行控制,其主机硬件和野外地面设备轻便,不足之处是操作系统出现问题维护比较麻烦,缺少采集数据质量控制的软件;System Four则以Win-dows2000为软件平台,应用软件功能丰富,它自带质量控制软件Source Aware,能有效监视数据采集质量,缺点是仪器主机体积较大,操作系统容易受病毒感染。本文根据两种仪器在实际生产中的使用情况,从软硬件组成、技术性能、操作使用、常见故障、对特殊地形的适应程度等方面对两种系统进行了对比,并分析了它们的优点与不足。 展开更多
关键词 408UL system FOUR 采集系统 系统对比
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Comparative Analysis on Pesticide Management System between America and China
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作者 Cunzheng ZHANG Yong GONG +1 位作者 Weili SHAN Xianjin LIU 《Asian Agricultural Research》 2013年第5期144-147,共4页
The production and usage amount of pesticides in US rank the leading position in the world. On the basis of protecting the environment and human health, US government has enacted a series of laws and regulations to no... The production and usage amount of pesticides in US rank the leading position in the world. On the basis of protecting the environment and human health, US government has enacted a series of laws and regulations to normalize and manage the production and use of pesticides so as to ensure the development of modern agriculture. In this paper, US pesticide management system is briefly reviewed and compared with the pesticide management system of China, which may provide good reference for china in establishing its own management system and make steps towards the international standard. 展开更多
关键词 PESTICIDE MANAGEMENT system of AMERICA PESTICIDE m
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A Decision Support Framework for the Choice of Languages and Methods for the Design of Real Time Embedded Systems
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作者 Valéry M. Monthe Laurent Nana +1 位作者 Georges E. Kouamou Claude Tangha 《Journal of Software Engineering and Applications》 2016年第7期353-397,共45页
The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems i... The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summary table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers. 展开更多
关键词 Design Method Modelling Language Real-Time system Embedded system comparison Criteria
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Partial stability of a class of large-scale systems with partiallystable isolated subsystems
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作者 JianJigui LuoHaigeng LiaoXiaoxin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期346-350,共5页
The problem of partial stability is investigated for a class of continuous-time large-scale systems. Under assumption that the null solution of the isolated subsystems is stable, based on decomposition-aggregation met... The problem of partial stability is investigated for a class of continuous-time large-scale systems. Under assumption that the null solution of the isolated subsystems is stable, based on decomposition-aggregation methods and Lyapunov second method, some theorems concerning the globally partial asymptotic stability and globally partial exponential stability are obtained via utilizing the inequality analysis technique and comparison technique. Finally, an example is presented to illustrate the results. 展开更多
关键词 large-scale systems partial stability INEQUALITY comparison principle Lyapunov function.
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TECHNICAL STABILITY OF NONLINEAR TIME-VARYING SYSTEMS WITH SMALL PARAMETERS
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作者 楚天广 王照林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第11期1264-1271,共8页
Technical stability:allowing quantitative estimation of trajectory behavior of a dynamical system over a given time interval was considered. Based on a differential comparison principle and a basic monotonicity condit... Technical stability:allowing quantitative estimation of trajectory behavior of a dynamical system over a given time interval was considered. Based on a differential comparison principle and a basic monotonicity condition, technical stability relative to certain prescribed state constraint sets of a class of nonlinear time-varying systems with small parameters was analyzed by means of vector Liapunov function method. Explicit criteria of technical stability are established in terms of coefficients of the system under consideration. Conditions under which the technical stability of the system can be derived from its reduced linear time-varying (LTV) system were further examined, as well as a condition for linearization approach to technical stability of general nonlinear systems. Also, a simple algebraic condition of exponential asymptotic stability of LTV systems is presented. Two illustrative examples are given to demonstrate the availability of the presently proposed method. 展开更多
关键词 nonlinear time-varying system small parameter technical stability vector comparison principle reduced system linearization technique exponential asymptotic stability
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松辽盆地宋芳屯构造带登娄库组油气来源及成藏过程
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作者 陆加敏 孙立东 +10 位作者 杨亮 姜振学 刘家军 李笑梅 施立冬 蔡壮 李卓 杨威 缪欢 陈瑞华 孙伟豪 《大庆石油地质与开发》 北大核心 2025年第1期1-13,共13页
松辽盆地徐家围子区块宋芳屯构造带油气资源丰富,但油气来源及成藏过程复杂且不明确。通过有机地球化学、天然气地球化学、流体包裹体等手段,重点分析了宋芳屯构造带登娄库组的油气来源及成藏期次,并建立了多层系油气成藏模式。结果表明... 松辽盆地徐家围子区块宋芳屯构造带油气资源丰富,但油气来源及成藏过程复杂且不明确。通过有机地球化学、天然气地球化学、流体包裹体等手段,重点分析了宋芳屯构造带登娄库组的油气来源及成藏期次,并建立了多层系油气成藏模式。结果表明:宋芳屯构造带内登娄库组泥岩品质较差,主要为Ⅲ和Ⅱ2型,Ro为1.73%,处于高成熟阶段,徐西次凹沙河子组泥岩以好-很好烃源岩为主,有机质类型为Ⅲ-Ⅱ1型,Ro为2.55%,处于过成熟阶段;宋芳屯构造带登娄库组原油来源于宋芳屯构造带登娄库组泥岩和徐西次凹沙河子组泥岩,而宋芳屯构造带登娄库组天然气主要来源于徐西次凹的沙河子组泥岩;宋芳屯构造带油气运移期为距今89.6~67.5Ma,最大运移时期约为距今76.0Ma;登娄库组泥岩和沙河子组泥岩持续供烃是宋芳屯构造带油气成藏的物质基础,多层系砂岩泥岩互层与主干断裂、砂体对油气的输导为油气成藏的必要条件,生烃期与成藏期高度匹配是多层系油气成藏的关键,多种地质条件的耦合下形成了宋芳屯构造带多层系油气成藏模式。研究成果为松辽盆地的油气勘探提供了一定的理论支持。 展开更多
关键词 松辽盆地 宋芳屯构造带 登娄库组 油气系统 油源对比 成藏模式
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