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Defected Ground Structure Multiple Input-Output Antenna For Wireless Applications
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作者 Ramya Sridhar Vijayalakshimi Patteeswaran 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2109-2122,共14页
In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Elect... In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Electromagnetic Radiation Structures(ERS)is composed of multiple radiating elements.These MIMO antennas are designed and analyzed with and without DGS.The feeding is introduced by a microstrip-fed line to significantly moderate the radiating structure’s overall size,which is 60×40×1 mm.The high directivity and divergence characteristics are attained by introducing the microstripfed lines perpendicular to each other.And the projected MIMO antenna structures are compared with others by using parameters like Return Loss(RL),Voltage Standing Wave Ratio(VSWR),Radiation Pattern(RP),radiation efficiency,and directivity.The same MIMO set-up is redesigned with DGS,and the resultant parameters are compared.Finally,the Multiple Input and Multiple Output Radiating Structures with and without DGS are compared for result considerations like RL,VSWR,RP,radiation efficiency,and directivity.This projected antenna displays an omnidirectional RP with moderate gain,which is highly recommended for human healthcare applications.By introducing the defected ground structure in bottom layer the lower cut-off frequencies of 2.3,4.5 and 6.0 GHz are achieved with few biological effects on radio propagation in human body communications.The proposed design covers numerous well-known wireless standards,along with dual-function DGS slots,and it can be easily integrated into Wireless Body Area Networks(WBAN)in medical applications.This WBAN links the autonomous nodes that may be situated either in the clothes,on-body or beneath the skin of a person.This system typically advances the complete human body and the inter-connected nodes through a wireless communication channel. 展开更多
关键词 MIMO-multiple input multiple output defected ground structure WBAN-wireless body area networks ULTRA-WIDEBAND voltage standing wave ratio
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Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming
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作者 Zhongyang Wang Youqing Wang Zdzisław Kowalczuk 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期131-140,共10页
In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed metho... In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection. 展开更多
关键词 Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)
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Analysis on Input-Output in Rice Cultivation Based on Cobb-Douglas Production Function 被引量:2
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作者 高雷 《Agricultural Science & Technology》 CAS 2012年第4期716-718,共3页
[Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-... [Objective] To analyze the input and output in rice cultivation based on CD function. [Method] Based on the input factors, Cobb-Douglas production (CD) function was used to do the quantitative analysis on the input-output in rice production with rice growers as the objective. [Result] Considering the substitution effect of labor in- put and capital input, under the same technical conditions, the effect of increasing labor input on the rice production in per 667 m2 was negative, based on which 2 pieces of policy suggestions were put forward to promote the transfer of surplus la- bor force of rice growers and ensure the capital supply for rice production. [Conclusion] This study laid the foundation for the realization of reasonable allocation of rice production resources. 展开更多
关键词 Cobb-Douglas production function Rice cultivation input output
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基于Input-Output模型的新疆水资源合理配置研究 被引量:2
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作者 刘爽 李莉 荣伟 《江西农业学报》 CAS 2018年第5期101-105,109,共6页
根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量... 根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量远高于其产出效益,第三产业和生态环境产业的水资源消耗呈现递减趋势。此外,工业和建筑业的水资源配置较为合理。最后,为促进新疆水资源优化配置提出了相应的对策建议。 展开更多
关键词 水资源 合理配置 input-output模型 新疆
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An Efficient MMI SOI Splitter with Multimode Input/Output Waveguides
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作者 方青 贺月娇 +2 位作者 辛红丽 李芳 刘育梁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期276-280,共5页
A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for... A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for use in fiber optics communication systems.The fabricated device exhibits low loss and good coupling uniformity.The excess loss is lower than 0 8dB,and the uniformity is 0 45dB at the wavelength of 1550nm.Moreover,the polarization dependent loss is lower than 0 7dB at 1550nm.The device size is only 2mm×10mm. 展开更多
关键词 multimode interference power splitter SOI multimode input/output waveguides
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Agricultural Input and Output in Jiangsu Province with Case Analysis
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作者 杜华章 《Agricultural Science & Technology》 CAS 2014年第11期2006-2010,2025,共6页
[Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation w... [Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation were made on agricultural input and output in Jiangsu during 1990-2012 as per factor analysis and regression analysis. [Result] The result of factor analysis showed that since the 1990s, the comprehensive efficiency of agricultural input/output in Jiangsu was growing and in-put/output of agriculture, forestry, animal husbandry and fishery, crop farming, and of food production were extracted, whose scores reflect the changes of input/output ef-ficiencies in terms of agriculture, forestry, animal husbandry, fishery, crop farming and food production in the two decades. The results of regression analysis indicated that the effects of the three indices on agricultural output tended to be volatile and the influence degrees were concluded also by regression parameters. [Conclusion] The research provides theoretical references for agricultural input/output structure in Jiangsu Province. 展开更多
关键词 Agriculture input/output Factor analysis Regression analysis Jiangsu Province
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On the Balance Between “Input” and “Output” in College English Teaching
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作者 刘芳 《海外英语》 2016年第1期239-240,242,共3页
The current college English teaching is usually associated with two discouraging words—"time-consuming"and"inefficient", which badly demands some urgent solutions. On the basis of Krashen's In... The current college English teaching is usually associated with two discouraging words—"time-consuming"and"inefficient", which badly demands some urgent solutions. On the basis of Krashen's Input Hypothesis and Swain's Output Hypothesis, this paper elaborates the indispensable and critical roles respectively of input and output in language learning, and proposes a concept of balanced input and output in college English teaching. The paper also presents some personal suggestions as to how to bring the balance into teaching. 展开更多
关键词 COLLEGE English TEACHING input output BALANCE
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Input and Output Balance to Assist in Language Competence
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作者 马滢颖 《海外英语》 2011年第11X期109-110,共2页
Second Language Acquisition(SLA) education in China suffers from an imbalance between language input and output.Reading and listening are the dominate methods used in the classroom,while speaking and writing are used ... Second Language Acquisition(SLA) education in China suffers from an imbalance between language input and output.Reading and listening are the dominate methods used in the classroom,while speaking and writing are used far less.This paper examines the results that are caused by this imbalanced development of comprehensible output and input.Alternative solutions are examined.The results show the limitations in students' abilities that are commonly based on the current methods of teaching.The implications are that policy makers,curriculum developers and teachers should strive to balance the amount of comprehensible input and output through various means. 展开更多
关键词 SECOND LANGUAGE ACQUISITION LANGUAGE input and output
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语言学习过程中的“Input”和“Output”类课程特点分析
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作者 田凤俊 《教育教学论坛》 2010年第11期165-166,共2页
"Input"和"Output"作为语言学习和运用的两个主要方式,历来备受语言研究者和学习者的关注。因此,有关它们的理论著述和观点也颇多。但主要是如何就二者能很好的在中国英语外语环境中得以有效地应用和实践,如在高校... "Input"和"Output"作为语言学习和运用的两个主要方式,历来备受语言研究者和学习者的关注。因此,有关它们的理论著述和观点也颇多。但主要是如何就二者能很好的在中国英语外语环境中得以有效地应用和实践,如在高校英语专业课程群中得以很好的实施则显得非常必要和实用。将所有英语外语课程按照"Input"和"Output"进行分类并按照课程建模的方式进行课程教学和人才培养是本文讨论的主要任务。 展开更多
关键词 input”和“output 语言学习和习得 课程建模 英语外语教学
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From Input to Output-Exploring the Role of Intake in English Learning
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作者 黄志红 《山东师范大学外国语学院学报(基础英语教育)》 2007年第4期7-17,54,共12页
This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not t... This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not take place directly from input to output.In each sqecific part of L2 acquisition process,intake plays various important roles such as filtering,facilitating in comprehensible input and processing in pushed output.In the Chinese foreign language teaching context,it is also found that L2 acquisition is an arduous task for learners to extract information from the input,utilize it in forming a grammar and produce target language forms accurately and fluently.It is the same with L2 teachers who need to play their roles of a controller,a corrector,an organizer and a prompter in the learning process. 展开更多
关键词 英语教学 第二语言习得 中学 输入 输出 消化吸收
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Input and Output in Second Language Acquisition
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作者 李志远 《学周刊(下旬)》 2015年第7期7-7,共1页
Input and output are two major terminal actions in second language acquisition.For these two actions scholars have carried out a great number of researches.Among them the most famous are Krashen’s Input Hypothesis an... Input and output are two major terminal actions in second language acquisition.For these two actions scholars have carried out a great number of researches.Among them the most famous are Krashen’s Input Hypothesis and Output Hypothesis. 展开更多
关键词 英语学习 学习方法 阅读知识 阅读材料
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The Study of Strategies in College English Translation Teaching from the Perspective of Input and Output Theory
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作者 刘莹 《海外英语》 2014年第14期135-136,共2页
Research on SLA gives highlights to English translation teaching. The second language acquisition is a cognitive process of understanding and outputting the second language by making use of strategies, which contains ... Research on SLA gives highlights to English translation teaching. The second language acquisition is a cognitive process of understanding and outputting the second language by making use of strategies, which contains language input, learners' linguistic knowledge, and language output. This paper analyzes language input and output theory and then proposes that we should stress language input by practice and interaction and at the same time focus on the role of language output in college English translation teaching. 展开更多
关键词 ENGLISH TRANSLATION TEACHING LANGUAGE input langua
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Input和Output理论在高职高专英语口语教学中的应用*
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作者 孙淑梅 《贵州商业高等专科学校学报》 2012年第2期76-78,共3页
影响高职高专学生英语口语训练的因素有很多。从Input和Output(输入和输出)理论的角度,分析影响口语发展障碍的成因,并从教、学双重角度考虑,提出相应的教学对策。
关键词 输入输出 英语口语 障碍 教学对策
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A Pilot Study on Task Frequency Effects of Input-Output Cycles on EFL Learners’Oral Proficiency
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作者 王玉山 《中国校外教育》 2012年第9期40-41,共2页
This paper gives a report of the findings of a pilot study on task frequency effects of input-output cycles on EFL learners'oral proficiency.The results showed that the experimental group made greater progress in ... This paper gives a report of the findings of a pilot study on task frequency effects of input-output cycles on EFL learners'oral proficiency.The results showed that the experimental group made greater progress in complexity and accuracy than control groups.We may come to the conclusion that circular input-out benefits learners most.The study may give some insights for foreign language teachers to give second language learners appropriate tasks in listening and speaking classes. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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Adaptive Control Based on Neural Networks for an Uncertain 2-DOF Helicopter System With Input Deadzone and Output Constraints 被引量:15
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作者 Yuncheng Ouyang Lu Dong +1 位作者 Lei Xue Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期807-815,共9页
In this paper, a study of control for an uncertain2-degree of freedom(DOF) helicopter system is given. The2-DOF helicopter is subject to input deadzone and output constraints. In order to cope with system uncertaintie... In this paper, a study of control for an uncertain2-degree of freedom(DOF) helicopter system is given. The2-DOF helicopter is subject to input deadzone and output constraints. In order to cope with system uncertainties and input deadzone, the neural network technique is introduced because of its capability in approximation. In order to update the weights of the neural network, an adaptive control method is utilized to improve the system adaptability. Furthermore, the integral barrier Lyapunov function(IBLF) is adopt in control design to guarantee the condition of output constraints and boundedness of the corresponding tracking errors. The Lyapunov direct method is applied in the control design to analyze system stability and convergence. Finally, numerical simulations are conducted to prove the feasibility and effectiveness of the proposed control based on the model of Quanser's 2-DOF helicopter. 展开更多
关键词 2-degree of FREEDOM (DOF) helicopter adaptive control input DEADZONE integral barrier Lyapunov function neural networks output constraints
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Robust Output Feedback Control for a Class of Nonlinear Systems with Input Unmodeled Dynamics 被引量:4
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作者 Ming-Zhe Hou Ai-Guo Wu Guang-Ren Duan 《International Journal of Automation and computing》 EI 2008年第3期307-312,共6页
The robust global stabilization problem of a class of uncertain nonlinear systems with input unmodeled dynamics is considered using output feedback, where the uncertain nonlinear terms satisfy a far more relaxed condi... The robust global stabilization problem of a class of uncertain nonlinear systems with input unmodeled dynamics is considered using output feedback, where the uncertain nonlinear terms satisfy a far more relaxed condition than the existing triangulartype condition. Under the assumption that the input unmodeled dynamics is minimum-phase and of relative degree zero, a dynamic output compensator is explicitly constructed based on the nonseparation principle. An example illustrates the usefulness of the proposed method. 展开更多
关键词 Nonlinear systems global stabilization output feedback input unmodeled dynamics high gain
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Control design for the nonlinear benchmark problem via the output regulation method 被引量:4
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作者 JieHUANG GuoqiangHU 《控制理论与应用(英文版)》 EI 2004年第1期11-19,共9页
The problem of designing a feedback controller to achieve asymptotic disturbance rejection / attenuation while maintaining good transient response in the RTAC system is known as a benchmark nonlinear control problem, ... The problem of designing a feedback controller to achieve asymptotic disturbance rejection / attenuation while maintaining good transient response in the RTAC system is known as a benchmark nonlinear control problem, which has been an intensive research subject since 1995. In this paper, we will further investigate the solvability of the robust disturbance rejection problem of the RTAC system by the measurement output feedback control based on the robust output regulation method. We have obtained a design by overcoming two major obstacles: find a closed-form solution of the regulator equations; and devise a nonlinear internal model to account for non-polynomial nonlinearities. 展开更多
关键词 RTAC system Robust control Nonlinear control output regulation problem Disturbance rejection
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Comparative and Empirical Study on Vegetable Input-Output Efficiency of Suburban and Rural Areas 被引量:1
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作者 Li LI Jianmin SHI 《Asian Agricultural Research》 2015年第2期23-28 33,33,共7页
On the basis of comparative analysis on the vegetable input-output efficiency of suburban and rural areas in 2011- 2012,this paper made co-integration test,impulse response and variance decomposition for the vegetable... On the basis of comparative analysis on the vegetable input-output efficiency of suburban and rural areas in 2011- 2012,this paper made co-integration test,impulse response and variance decomposition for the vegetable input-output relationship of suburban areas in 1998-2012. Comparative analysis indicated that the vegetable input-output benefit of suburban area declines,while that of rural area rises; empirical analysis indicated that there is a long-term stable relationship between labor cost of vegetable planting and vegetable income and between material cost of vegetable planting and vegetable income,but the vegetable income itself has certain lag effect,followed by material cost,and the labor cost has minimum influence. Finally,it came up with recommendations for improving suburban vegetable input-output relationship,including improving vegetable input security mechanism,improving farmers' quality and innovation ability,and increasing technological input. 展开更多
关键词 VEGETABLE input VEGETABLE output SUBURBAN area Rur
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Direction-of-arrival estimation for co-located multiple-input multiple-output radar using structural sparsity Bayesian learning 被引量:4
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作者 文方青 张弓 贲德 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期70-76,共7页
This paper addresses the direction of arrival (DOA) estimation problem for the co-located multiple-input multiple- output (MIMO) radar with random arrays. The spatially distributed sparsity of the targets in the b... This paper addresses the direction of arrival (DOA) estimation problem for the co-located multiple-input multiple- output (MIMO) radar with random arrays. The spatially distributed sparsity of the targets in the background makes com- pressive sensing (CS) desirable for DOA estimation. A spatial CS framework is presented, which links the DOA estimation problem to support recovery from a known over-complete dictionary. A modified statistical model is developed to ac- curately represent the intra-block correlation of the received signal. A structural sparsity Bayesian learning algorithm is proposed for the sparse recovery problem. The proposed algorithm, which exploits intra-signal correlation, is capable being applied to limited data support and low signal-to-noise ratio (SNR) scene. Furthermore, the proposed algorithm has less computation load compared to the classical Bayesian algorithm. Simulation results show that the proposed algorithm has a more accurate DOA estimation than the traditional multiple signal classification (MUSIC) algorithm and other CS recovery algorithms. 展开更多
关键词 multiple-input multiple-output radar random arrays direction of arrival estimation sparseBayesian learning
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Fundamental Theories of Second Language Acquisition: The Input Hypothesis, the Output hypothesis, and the Interaction Hypothesis 被引量:1
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作者 ZHAO Congmin 《Sino-US English Teaching》 2021年第7期192-195,共4页
In the field of applied linguistics,several hypotheses have been proposed for second language acquisition:the Input Hypothesis,the Output hypothesis,and the Interaction Hypothesis.They address the fundamental componen... In the field of applied linguistics,several hypotheses have been proposed for second language acquisition:the Input Hypothesis,the Output hypothesis,and the Interaction Hypothesis.They address the fundamental components of successful second language acquisition respectively.This paper introduces these hypotheses and constructs a comprehensive picture based on them。 展开更多
关键词 input output INTERACTION
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