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Six-Element Yagi Array Designs Using Central Force Optimization with Pseudo Random Negative Gravity 被引量:1
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作者 Richard A. Formato 《Wireless Engineering and Technology》 2021年第3期23-51,共29页
A six-element Yagi-Uda array is optimally designed using Central Force Optimization (CFO) with a small amount of pseudo randomly injected negative gravity. CFO is a simple, deterministic metaheuristic analogizing grav... A six-element Yagi-Uda array is optimally designed using Central Force Optimization (CFO) with a small amount of pseudo randomly injected negative gravity. CFO is a simple, deterministic metaheuristic analogizing gravitational kinematics (motion of masses under the influence of gravity). It has been very effective in addressing a wide range of antenna and other problems and normally employs only positive gravity. With positive gravity the six element CFO-designed Yagi array described here exhibits excellent performance with respect to the objectives of impedance bandwidth and forward gain. This paper addresses the question of what happens when a small amount of negative gravity is injected into the CFO algorithm. Does doing so have any effect, beneficial, negative or neutral? In this particular case negative gravity improves CFO’s exploration and creates a region of optimality containing many designs that perform about as well as or better than the array discovered with only positive gravity. Without some negative gravity these array configurations are overlooked. This Yagi-Uda array design example suggests that antennas optimized or designed using deterministic CFO may well benefit by including a small amount of negative gravity, and that the negative gravity approach merits further study. 展开更多
关键词 ANTENNA 6-element Array Yagi Yagi-Uda ARRAY Impedance Bandwidth VSWR Forward Gain Antenna Design Antenna Optimization Central Force Optimization CFO Deterministic Metaheuristic Evolutionary Algorithm GRAVITY Gravitational Kinematics Exploration Exploitation
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Research on Electric Impedance Spectroscopy of Living Cell Suspensions by a Chip with Microelectrodes 被引量:1
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作者 Xing Yang Zhaoying Zhou +2 位作者 Mingfei Xiao Ying Wu Shangfeng Liu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期429-432,共4页
A microfabricated electrical impedance spectroscopy (EIS) chip with microelectrodes was developed.The substrate and the electrodes of the chip were made of glass and gold,respectively.The experimental results demonstr... A microfabricated electrical impedance spectroscopy (EIS) chip with microelectrodes was developed.The substrate and the electrodes of the chip were made of glass and gold,respectively.The experimental results demonstrated that the EIS-chip could distinguish different solutions (physiological saline,culture medium,living cell suspension etc.) by scanning from 10Hz to 45kHz.A 6-element circuit model was used for fitting the real part and the imaginary part admittance curves of the living cell suspension.An actual circuit was also built and tested to verify the 6-element circuit model proposed.The micro-EIS chip has several advantages including the use of small sample volumes,high resolution and ease of operation.It shows good application prospects in the areas of cellular electrophysioiogy,drug screening and bio-sensors etc. 展开更多
关键词 electrical impedance spectroscopy(EIS) MICROELECTRODE living cell suspension 6-element
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Real-time measurement of atmospheric parameters for the 127-element adaptive optics system of 1.8-m telescope 被引量:1
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作者 母杰 郑文佳 +1 位作者 李梅 饶长辉 《Chinese Optics Letters》 SCIE EI CAS CSCD 2012年第12期1-4,共4页
A real-time method for measuring atmospheric parameters based on co-processor field-programmable gate array (FPGA) and main processor digital signal processing (DSP) is proposed for ground-based telescopes with ad... A real-time method for measuring atmospheric parameters based on co-processor field-programmable gate array (FPGA) and main processor digital signal processing (DSP) is proposed for ground-based telescopes with adaptive optics (AO) systems. Coherence length, outer scale, average wind speed, and coherence time are estimated according to closed-loop data on the residual slopes and the corrected voltages of AO systems. This letter introduces the principle and architecture design of the proposed method, which is successfully applied in the 127-element AO system of the 1.8-m telescope of Yunnan Astronomical Observatory. The method enables real-time atmospheric observations with the same object and path of the AO system. This method is also applicable to extended objects. 展开更多
关键词 real time Real-time measurement of atmospheric parameters for the 127-element adaptive optics system of 1.8-m telescope AO
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Word Generative Grammar——an Extensible 6-element System:{V_T,V_N,θ, L,S,P}
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作者 CHEN Xu, WANG Zhi min, GAO Qing shi (Information Engineering School, University of Science & Technology, Beijing 100083, P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2003年第2期27-33,共7页
On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of s... On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of set' s types L (e.g., ordered set, continuous(descending) ordered set, unordered set, coupled set, coordinate, et al.), and generalizes them toother word types of natural language, thus presenting the generative grammar for words―anextensible 6-element formal system {V_T, V_N, θ, L, S, P}, and takeing time words in naturallanguage as example for detailed discussion. With the colorfulness of time words of naturallanguage, time words for different natural languages assume different meaning. Generative grammarfor time words can generate not only different time words, but also their semantics (Generativegrammar of Chomsky can only produce all right sentences instead of semantics), and then, generalizesthem to other word types, e.g., accurate measure words, adjectives, etc. 展开更多
关键词 natural language formal system word generative grammar extensible6-element system
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SIMPLE OCKHAM ALGEBRAS
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作者 FANG JIE Department of Mathematics, Zhongshan University, Guangzhou 510271, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1996年第2期213-218,共6页
An algeber L is said to be simple, if its congruence lattice Con L reduces to the 2-elementchain {ω,v}. This paper describes the structure of finite simple Ockham algebras.
关键词 Ockham algebra Simple algebra Congruence lattic 2-element chain
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