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Seismic wave input method for three-dimensional soil-structure dynamic interaction analysis based on the substructure of artificial boundaries 被引量:20
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作者 Liu Jingbo Tan Hui +2 位作者 Bao Xin Wang Dongyang Li Shutao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期747-758,共12页
The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident... The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the fi nite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave fi eld on the nodes of the substructure composed of elements that contain artifi cial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artifi cial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplifi ed by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verifi ed by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves. 展开更多
关键词 soil-structure dynamic interaction SEISMIC WAVE input WAVE method EQUIVALENT input SEISMIC loads SUBSTRUCTURE of artifi cial boundaries
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Study on Pinyin-Stroke Coding Input Method For Chinese Characters
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作者 CHEN Qin-wu LIU Rui-shun LIU Xiu-feng 《微计算机信息》 2010年第36期255-257,279,共4页
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A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system 被引量:2
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作者 李永倩 李晓娟 +1 位作者 范寒柏 张立欣 《Optoelectronics Letters》 EI 2018年第1期53-56,共4页
A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne... A method for the optimal fiber input power determination is presented by employing the variation characteristics of signal to noise ratio(SNR) in spontaneous Brillouin-scattering-based sensing system. And a heterodyne detection system is constructed for measuring the Brillouin scattering spectra with different fiber input powers. The Brillouin spectrum width and system SNR can be simultaneously measured from these spectra, and the optimal fiber input power can be obtained from such information. In the experiment, for 48.8-km-long standard single-mode fiber(SSMF), the optimal fiber input power values are all approximately 0 dBm obtained by the maximum SNR position for different local oscillator power values and average times. 展开更多
关键词 SNR A useful method for determination of optimal fiber input power in spontaneous Brillouin-scattering-based sensing system
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Application of Reciting Methods on Secondary School Oral English Learning — based on Krashen's Input Hypothesis
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作者 严佳佳 《海外英语》 2015年第20期228-230,共3页
It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypoth... It has been found that a large amount of students are not able to communicate fluently and lack self-confidence. Therefore, they lost interest in English. This paper first introduces Stephen Krashen's Input Hypothesis. Through analyzing the influencing factors of oral English learning and the significance of reciting methods, the article explored the concrete reciting methods. I hope it will shed some light on the English teaching and learning practice. 展开更多
关键词 SECONDARY SCHOOL students ORAL English input HYPOTHESIS reciting methodS
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Development of service industry in Shandong province based on input-output method
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作者 ZHOU Jiang-tao 《Ecological Economy》 2018年第1期28-36,共9页
Based on 2012 input-output table of Shandong province and the official statistics, this article uses the input-output analysis method to build the input-output table. On the basis of the development of service industr... Based on 2012 input-output table of Shandong province and the official statistics, this article uses the input-output analysis method to build the input-output table. On the basis of the development of service industry in Shandong province's ability, we make a theoretical analysis framework of a comprehensive in-depth analysis on pull employment, creatively will cost tax rate, fully and completely labor capital and the combination of both the industry development space. So that the industry's ability to pull the employment can be considered, and to realize rapid and sustained development of service industry in Shandong province. 展开更多
关键词 input-output method service industry EMPLOYMENT formats
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A METHOD FOR CALCULATING TRANSIENT FUNCTIONS OF EQUIVALENT DETERMINISTIC INPUT
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《Chinese Journal of Aeronautics》 SCIE EI CAS 1988年第2期98-104,共7页
In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-... In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-mean-square of the responses of a linear time-invariant system to stationary multiple random inputs in the time domain.The method is applicable in the study of flight of airplanes in atmospheric turbulence and is also useful for general engineering applications of stochastc processes control. 展开更多
关键词 A method FOR CALCULATING TRANSIENT FUNCTIONS OF EQUIVALENT DETERMINISTIC input
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中国绿色就业规模测算及其效应分析
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作者 徐强 苗彤 《统计与信息论坛》 北大核心 2026年第1期1-18,共18页
绿色经济是重要的国家发展战略,当前中国正步入绿色转型的关键时期。为洞悉绿色转型对中国就业市场的影响,采用投入产出法和结构分解法测算2012—2020年中国绿色就业规模,量化评估中国绿色产业的就业吸纳能力,并系统性剖析劳动生产率、... 绿色经济是重要的国家发展战略,当前中国正步入绿色转型的关键时期。为洞悉绿色转型对中国就业市场的影响,采用投入产出法和结构分解法测算2012—2020年中国绿色就业规模,量化评估中国绿色产业的就业吸纳能力,并系统性剖析劳动生产率、产业结构调整以及最终需求规模波动对绿色就业规模的影响。测算结果表明,2012—2020年绿色产业增加值持续稳定增长,绿色就业规模呈先减后增趋势,绿色就业规模占历年就业总数的比重基本维持在4%~5%之间,与国际既有研究的测算结果大致处于同一水平。从就业效应来看,绿色产业的就业创造效应超过了替代效益,当前绿色产业正处于就业吸纳阶段,推动就业规模有效扩大。从就业规模影响因素来看,劳动生产率、产业结构调整以及最终需求规模波动对不同类型产业就业的影响存在明显异质性,服务业在绿色转型过程中为稳定就业市场发挥了重要作用。从拓展性研究来看,绿色转型背景下绿色产业的劳动力需求向高技能和低技能劳动者倾斜,呈现技能偏态性、劳动力“极化”等特征。通过以上分析,提出合理选择绿色转型模式、完善劳动力市场服务体系、完善职业培训体系等政策建议,为政府相关部门制定产业转型策略提供参考,为化解绿色转型过程中劳动力市场的矛盾和冲突提供经验支持。 展开更多
关键词 绿色经济 绿色就业 投入产出法 结构分解法 就业效应
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农业全产业链规模对农产品增加值收益的影响研究
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作者 罗良清 章标彪 郭玉帑 《南昌大学学报(人文社会科学版)》 北大核心 2026年第1期86-100,共15页
农业全产业链发展是实现农业增值增效、促进乡村振兴的重要手段。通过界定农业全产业链产业范围,构建农业全产业链增加值测算框架,对中国30个省(自治区、直辖市)农业全产业链规模进行测算,并运用双向固定效应模型实证检验农业全产业链... 农业全产业链发展是实现农业增值增效、促进乡村振兴的重要手段。通过界定农业全产业链产业范围,构建农业全产业链增加值测算框架,对中国30个省(自治区、直辖市)农业全产业链规模进行测算,并运用双向固定效应模型实证检验农业全产业链规模对农产品增加值收益的影响。结果表明:各地区农业全产业链规模均呈上升趋势,且农业全产业链规模能够显著提升农产品增加值收益。从作用机制来看,农业全产业链规模可以通过加快农业产业集聚、提高农业数字化水平来提升农产品增加值收益;地区交通基础设施水平能强化农业全产业链规模对农产品增加值收益的正向影响,但对国内外增加值收益的影响存在差异。从异质性来看,农业全产业链规模对粮食产销平衡区、西部地区和畜牧养殖及畜产品加工地区的农产品增加值收益提升作用最为明显。因此,应充分发挥政策力量,加快推动农业全产业链建设,实施差异化发展战略,从而提升农业综合效益。 展开更多
关键词 农业全产业链 增加值测算 投入产出法 农产品增加值收益
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数字经济全口径增加值核算方法研究
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作者 任雪 秦瑶 +1 位作者 周先东 薛健 《当代经济科学》 北大核心 2026年第1期1-16,共16页
随着数字经济统计工作进入实践阶段,数字经济核心产业和融合产业增加值核算面临的若干复杂问题逐步凸显,制约了中国政府部门数字经济统计工作发展。在全面梳理总结国内外数字经济统计核算研究现状的基础上,以《数字经济及其核心产业统... 随着数字经济统计工作进入实践阶段,数字经济核心产业和融合产业增加值核算面临的若干复杂问题逐步凸显,制约了中国政府部门数字经济统计工作发展。在全面梳理总结国内外数字经济统计核算研究现状的基础上,以《数字经济及其核心产业统计分类(2021)》为指导,重点讨论数字经济统计内涵,优化数字经济增加值核算范围,深入研究中国数字经济全口径增加值统计核算方法,在数据来源、核算方法和统计制度方面进行探索创新,提出可操作、可复制和可推广的一揽子数字经济全口径增加值核算方案。以重庆市为例,对数字经济全口径增加值核算方案进行试算验证。结果表明,该核算方案在核算方法思路、核算基础数据依赖、核算系数专项调查方案等方面具有科学性和实用性,能够为全国及各地区统计系统提供可复制、可参考的核算框架。据此为数字经济增加值核算提供新的思路和方法,为相关部门制定和完善中国数字经济统计核算制度的政策建议提供有益参考。 展开更多
关键词 数字经济统计 核心产业 融合产业 投入产出表 增加值 核算范围 核算方法
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Design of space-centered interaction using invisible and intangible spatial inputs
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作者 David Jean Kwangjin Hong Keechul Jung 《Journal of Measurement Science and Instrumentation》 CAS 2012年第2期137-145,共9页
In this paper,we investigate methodologies to improve direct-touch interaction on invisible and intangible spatial input.We firstly discuss about the motive of looking for a new input method for whole body interaction... In this paper,we investigate methodologies to improve direct-touch interaction on invisible and intangible spatial input.We firstly discuss about the motive of looking for a new input method for whole body interaction and how it can be meaningful.We also describe the role that can play spatial interaction to improve the freedom of interaction for a user.We propose a method of spatial centered interaction using invisible and intangible spatial inputs.However,given their lack of tactile feedback and visual representation,direct touch interaction on such input can be confused.In order to make a step toward understanding causes and solutions for such phenomena,we made 2 user experiments.In the first one,we test 5 setups of helper that provide information of the location of the input by constraining the dimension it is located at.The results show that using marker on the ground and a relationship with the height of the user’s body improve significantly the locative task.In the second experiment,we create a dancing game using invisible and intangible spatial inputs and we stress the results obtained in the first experiment within this cognitively demanding context.Results show that the same setup of helper is still providing very good results in that context. 展开更多
关键词 human-computer interaction(HCI) spatial centered interaction whole body interaction input method
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中国家庭消费水足迹变化趋势及驱动因素分析
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作者 刘伟 郭禹涵 +3 位作者 司玉梅 葛榛子 许宝玲 汪峰 《生态经济》 北大核心 2026年第3期197-206,共10页
为厘清新消费格局下我国家庭消费水足迹变迁现状及关键驱动因素,基于2014、2020年中国家庭追踪调查数据库,结合蓝水与灰水双重视角,使用投入产出模型评估2014—2020年中国家庭消费水足迹的变化趋势,通过环境恩格尔曲线非参数估计、参数... 为厘清新消费格局下我国家庭消费水足迹变迁现状及关键驱动因素,基于2014、2020年中国家庭追踪调查数据库,结合蓝水与灰水双重视角,使用投入产出模型评估2014—2020年中国家庭消费水足迹的变化趋势,通过环境恩格尔曲线非参数估计、参数估计和Oaxaca-Blinder分解模型,量化家庭消费水足迹变化的主要驱动因素及其贡献程度。结果表明:(1)2014—2020年,中国家庭消费户均水足迹下降60.51%,其中户均直接灰水和间接灰水足迹分别下降了64.00%和65.40%。(2)家庭收入、家庭规模、户主教育程度、区域温度对水足迹变化有显著正向影响,缺水地区和水价较高地区水足迹往往相对较低。(3)家庭收入和其他家庭特征变量的变动分别导致水足迹增加了2920.403 m^(3)/户与477.616 m^(3)/户,而未解释变量的变动则贡献了最大的水足迹降低。 展开更多
关键词 蓝水足迹 灰水足迹 投入产出模型 环境恩格尔曲线 参数估计 OAXACA-BLINDER分解
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基于LSTM的卧式火管燃气式锅炉故障诊断研究
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作者 卢卫华 卢文槿 《电子设计工程》 2026年第4期63-67,共5页
燃气锅炉技术的不断发展使其内部结构越来越复杂,传统的故障诊断方法已难以满足实际需求。为此,研究了一种基于LSTM的卧式火管燃气式锅炉故障诊断方法。利用主元分析法选取表征数据作为输入量,建立与输出量-故障类型之间的对应关系。采... 燃气锅炉技术的不断发展使其内部结构越来越复杂,传统的故障诊断方法已难以满足实际需求。为此,研究了一种基于LSTM的卧式火管燃气式锅炉故障诊断方法。利用主元分析法选取表征数据作为输入量,建立与输出量-故障类型之间的对应关系。采集输入与输出量数据组成样本,对基于LSTM的诊断模型进行训练,利用训练好的模型实现卧式火管燃气式锅炉故障诊断。结果表明,LSTM模型的kappa系数更高,说明该模型在锅炉故障类型诊断任务中具有更高的准确性。 展开更多
关键词 LSTM 卧式火管燃气式锅炉 主元分析法 输入与输出量 故障诊断方法
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学历提升、资产负债与机会成本:破解“小镇做题家”困境的一个动态优化模型
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作者 侯冲聪 《重庆电力高等专科学校学报》 2026年第1期32-37,共6页
构建了一个“教育-就业”的动态优化模型,将受教育时长与教育投入作为选择变量,劳动力质量作为状态变量,利用变分法求得了微观个体接受高等教育的最优路径函数。研究发现,最优受教育时长与初始禀赋(资源)、助学贷款、收入预期同向变化,... 构建了一个“教育-就业”的动态优化模型,将受教育时长与教育投入作为选择变量,劳动力质量作为状态变量,利用变分法求得了微观个体接受高等教育的最优路径函数。研究发现,最优受教育时长与初始禀赋(资源)、助学贷款、收入预期同向变化,与机会成本反向变化。最优教育投入只受教育层次和教育成本函数占比的影响。研究结果为青年实现人生价值提供了有效指导,也为政策制定者提供了有益的理论参考。 展开更多
关键词 小镇做题家 教育投入与回报 “教育-就业”模型 变分法 最优路径
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Attitude Control Considering Variable Input Saturation Limit for a Spacecraft Equipped with Flywheels 被引量:7
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作者 TIAN Lin XU Shijie 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第3期437-445,共9页
A new attitude controller is proposed for spacecraft whose actuator has variable input saturation limit. There are three identical flywheels orthogonally mounted on board. Each rotor is driven by a brushless DC motor ... A new attitude controller is proposed for spacecraft whose actuator has variable input saturation limit. There are three identical flywheels orthogonally mounted on board. Each rotor is driven by a brushless DC motor (BLDCM). Models of spacecraft attitude dynamics and flywheel rotor driving motor electromechanics are discussed in detail. The controller design is similar to saturation limit linear assignment. An auxiliary parameter and a boundary coefficient are imported into the controller to guaran- tee system stability and improve control performance. A time-varying and state-dependent flywheel output torque saturation limit model is established. Stability of the closed-loop control system and asymptotic convergence of system states are proved via Lyapunov methods and LaSalle invariance principle. Boundedness of the auxiliary parameter ensures that the control objective can be achieved, while the boundary parameter's value makes a balance between system control performance and flywheel utilization efficiency. Compared with existing controllers, the newly developed controller with variable torque saturation limit can bring smoother control and faster system response. Numerical simulations validate the effectiveness of the controller. 展开更多
关键词 spacecraft attitude control variable input saturation limit Lyapunov methods flywheels brushless DC motor
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Carbon price impacts on sector cost:based on an input-output model of Beijing
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作者 Yijing Zhang Alun Gu Xiusheng Zhao 《Chinese Journal of Population,Resources and Environment》 2014年第3期239-246,共8页
Under the pressure of sustained growth in energy consumption in China,the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction,as well as a hotspot of r... Under the pressure of sustained growth in energy consumption in China,the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction,as well as a hotspot of research among scholars and policy makers.In this paper,the effects of carbon prices on Beijing's economy are analyzed using input-output tables.The carbon price costs are levied in accordance with the products'embodied carbon emission.By calculation,given the carbon price rate of 10 RMB/t-CO_2,the total carbon costs of Beijing account for approximately 0.22-0.40%of its gross revenue the same year.Among all industries,construction bears the largest carbon cost Among export sectors,the coal mining and washing industry has much higher export carbon price intensity than other industries.Apart from traditional energy-intensive industries,tertiary industry,which accounts for more than 70%of Beijing's economy,also bears a major carbon cost because of its large economic size.However,from 2007 to 2010,adjustment of the investment structure has reduced the emission intensity in investment sectors,contributing to the reduction of overall emissions and carbon price intensity. 展开更多
关键词 carbon PRICING input-OUTPUT method BEIJING EMBODIED emissions
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Dynamical Analysis of a Stochastic Predator-Prey System with Lévy Noise and Impulsive Toxicant Input
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作者 Xiaowan She Yuanfu Shao Taolin Zhang 《Journal of Applied Mathematics and Physics》 2020年第9期1999-2019,共21页
This paper established a modified Leslie-Gower and Holling-type IV stochastic predator-prey model with Lévy noise and impulsive toxicant input. We study the stability in distribution of solutions by inequality te... This paper established a modified Leslie-Gower and Holling-type IV stochastic predator-prey model with Lévy noise and impulsive toxicant input. We study the stability in distribution of solutions by inequality techniques and ergodic method. By comparison method and It<span style="white-space:nowrap;">&#244;</span>’s formula, we obtain the sufficient conditions for the survival of each species. Some numerical simulations are introduced to show the theoretical results. 展开更多
关键词 Lévy Noise Impulsive Toxicant input Comparison method Extinction and Persistence
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Finite element analysis of welding residual stress of aero engine blisk by controlling heat input
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作者 张学秋 杨建国 +3 位作者 陈绪辉 方洪渊 曲伸 王立诚 《China Welding》 EI CAS 2009年第2期70-74,共5页
In order to improve aero engine performance, it is necessary to reduce the welding residual stress of aero engine blisk. In this paper, finite element method was employed to simulate electron beam welding process of b... In order to improve aero engine performance, it is necessary to reduce the welding residual stress of aero engine blisk. In this paper, finite element method was employed to simulate electron beam welding process of blisk, in accordance with the deducing formula( p = kh ) , the heat input is changed with the weld depth to control welding residual stress of blisk. The calculation results show that welding residual stress of blisk can be controlled effectively by reducing the heat input on the conditions of meeting the demand of weld penetration and guaranteeing the welding quality, a new theoretical method and some numerical data are provided for controlling welding residual stress of blisk. 展开更多
关键词 heat input BLISK finite element method residual stress
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Case Study of a Chinese Girl's English Learning Methods in the American Elementary School
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作者 杨丽 《海外英语》 2017年第6期239-240,共2页
The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementa... The goal of this research is to explore a more successful method for Mainland Chinese students to learn English.This newmethod will be illustrated by using the experiences of my daughter while a student in an elementary school in the United States for oneyear.From the analysis of her learning experiences,the following conclusions were drawn:1) Immerse language learning is important tolanguage input.2) Phonics is an effective tool to improve reading for Chinese English 展开更多
关键词 language input learning methods PHONICS case study
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Structural Earthquake Resistance Design Using Energy Method
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作者 Hu Rongrong Civil Engineering Department, Huazhong University of Science and Technology, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第2期166-168,共3页
A summary of status of researches in the field of structural earthquake resistance design on energy concept is presented in three parts: earthquake input, demands on the structure and supplied capacity of the structur... A summary of status of researches in the field of structural earthquake resistance design on energy concept is presented in three parts: earthquake input, demands on the structure and supplied capacity of the structure. A new approach is proposed for analysis of the seismic response and damage criteria based on the momentary input energy. 展开更多
关键词 energy method maximum displacement momentary input energy.
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AN ANALYSIS ON INPUT IMPEDANCE OF A SINGLE MICROSTRIP PATCH IN THE QUASI-OPTICAL CAVITY
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作者 何宜军 杨铨让 《Journal of Electronics(China)》 1994年第2期150-155,共6页
The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green’s function. An expression is derived for the input impedance of a single microstrip patch cavity excited by a... The electromagnetic field integral equation in the quasi-optical cavity is obtained using the dyadic Green’s function. An expression is derived for the input impedance of a single microstrip patch cavity excited by a coaxial probe using moment method. The input impedance of a rectangular microstrip patch is discussed with this method. The result of this paper is similar to that of the microstrip antenna. This paper is of very important value for designing microstrip quasi-optical oscillator. 展开更多
关键词 OSCILLATOR Quasi-optical CAVITY input IMPEDANCE MICROSTRIP PATCH MOMENT method
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