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Formaldehyde degradation by UV/TiO_2/O_3 process using continuous flow mode 被引量:12
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作者 QI Hong SUN De-zhi CHI Guo-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1136-1140,共5页
The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount... The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/(m^3.min) and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained. 展开更多
关键词 UV/TiO2/O3 process FORMALDEHYDE continuous flow mode
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Modeling and Dynamic Analysis of Fractional-Order Buck Converter in Continuous Conduction Mode 被引量:1
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作者 Dawei Ding Zongzhi Li Nian Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第4期58-68,共11页
According to the fact that the actual inductor and actual capacitor are fractional, the mathematical and state-space averaging models of fractional order Buck converters in continuous conduction mode(CCM) are construc... According to the fact that the actual inductor and actual capacitor are fractional, the mathematical and state-space averaging models of fractional order Buck converters in continuous conduction mode(CCM) are constructed by using fractional calculus theory. Firstly, the parameter conditions that ensure that the converter working in CCM is given and transfer functions are derived. Also, the inductor current and the output voltage are analyzed. Then the difference between the mathematical model and the circuit model are analyzed, and the effect of fractional order is studied by comparing the integer order with fractional order model. Finally, the dynamic behavior of the current-controlled Buck converter is investigated. Simulation experiments are achieved via the use of Matlab/Simulink. The experimental results verify the correctness of theoretical analysis, the order should be taken as a significant parameter. When the order is taken as a bifurcation parameter, the dynamic behavior of the converter will be affected and bifurcation points will be changed as order varies. 展开更多
关键词 BUCK converter FRACTIONAL order continuous conduction mode(CCM) modeLING dynamic analysis BIFURCATION
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Optimization Transmission Efficiency with Driver Intention for Automotive Continuously Variable Transmission under Slip Mode 被引量:1
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作者 Ling Han Hui Zhang +1 位作者 Ruoyu Fang Hongxiang Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期332-348,共17页
This study proposes and experimentally validates an optimal integrated system to control the automotive continuously variable transmission(CVT)by Model Predictive Control(MPC)to achieve its expected transmission effic... This study proposes and experimentally validates an optimal integrated system to control the automotive continuously variable transmission(CVT)by Model Predictive Control(MPC)to achieve its expected transmission efficiency range.The control system framework consists of top and bottom layers.In the top layer,a driving intention recognition system is designed on the basis of fuzzy control strategy to determine the relationship between the driver intention and CVT target ratio at the corresponding time.In the bottom layer,a new slip state dynamic equation is obtained considering slip characteristics and its related constraints,and a clamping force bench is established.Innovatively,a joint controller based on model predictive control(MPC)is designed taking internal combustion engine torque and slip between the metal belt and pulley as optimization dual targets.A cycle is attained by solving the optimization target to achieve optimum engine torque and the input slip in real-time.Moreover,the new controller provides good robustness.Finally,performance is tested by actual CVT vehicles.Results show that compared with traditional control,the proposed control improves vehicle transmission efficiency by approximately 9.12%-9.35%with high accuracy. 展开更多
关键词 V-belt continuously variable transmission model predictive control Drive intention Slip mode Transmission efficiency
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Discrete Spectra and Continuous Spectrum of the BarotropicQuasi-Geostrophic Model-A Calculation ofMeteorological Data 被引量:1
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作者 张明华 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第4期487-506,共20页
Atmospheric disturbances at 300 hPa are decomposed into normal modes, referred as discrete—spectrum disturbances which can propagate freely in the observed zonal mean flow, and non—modal transient disturbances, refe... Atmospheric disturbances at 300 hPa are decomposed into normal modes, referred as discrete—spectrum disturbances which can propagate freely in the observed zonal mean flow, and non—modal transient disturbances, referred as continuous—spectrum disturbances which are continuously sheared and eventually absorbed by the zonal flow. It is shown that normal modes represent only a small fraction of the observed atmospheric disturbances, while continuous—spectrum disturbances represent the majority of observed disturbances, even when the basic flow is unstable. Daily variabilities of the observed continuous—spectrum disturbances are presented. They are shown to follow the results of wave—packet theory. Calculations suggest that there are abundant sources to excite continuous—spectrum disturbances in the atmosphere. 展开更多
关键词 Normal mode Discrete-spectrum continuous-SPECTRUM WAVE-PACKET
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Buckling Analysis of Tapered Continuous Columns by Using Modified Buckling Mode Shapes
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作者 Sina Toosi Akbar Esfandiari Ahmad Rahbar Ranji 《Journal of Marine Science and Application》 CSCD 2019年第2期160-166,共7页
Elastic critical buckling load of a column depends on various parameters,such as boundary conditions,material,and crosssection geometry.The main purpose of this work is to present a new method for investigating the bu... Elastic critical buckling load of a column depends on various parameters,such as boundary conditions,material,and crosssection geometry.The main purpose of this work is to present a new method for investigating the buckling load of tapered columns subjected to axial force.The proposed method is based on modified buckling mode shape of tapered structure and perturbation theory.The mode shape of the damaged structure can be expressed as a linear combination of mode shapes of the intact structure.Variations in length in piecewise form can be positive or negative.The method can be used for single-span and continuous columns.Comparison of results with those of finite element and Timoshenko methods shows the high accuracy and efficiency of the proposed method for detecting buckling load. 展开更多
关键词 BUCKLING analysis Tapered column.continuous COLUMNS Finite element method MODIFIED BUCKLING mode SHAPES
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Continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser
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作者 Rui-Jun Lan Guang-Hua Liu +6 位作者 Huan-Huan Min Tong-Yu Dai Ying-Jie Shen Peng-Hua Mu Cheng Ren De-Zhong Cao Xavier Mateos 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期357-359,共3页
A continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser is demonstrated with Fabry-Perot etalons in a simple linear cavity.The thermal lens effect is dramatically lowered by propagating the laser beam along the... A continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser is demonstrated with Fabry-Perot etalons in a simple linear cavity.The thermal lens effect is dramatically lowered by propagating the laser beam along the‘athermal’direction inside the laser crystal,which is very beneficial to removing the heat generated in the mode selection process.The maximum single-longitudinal-mode output power obtained is 64.8 mW at incident pump power of 4.7 W,corresponding to an optical conversion efficiency of 1.3%and a slope efficiency of 1.7%. 展开更多
关键词 continuous wave single-longitudinal mode Fabry-Perot etalon
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Damage assessment of a continuous beam bridge based on the strain mode
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作者 杜思义 《Journal of Chongqing University》 CAS 2003年第2期28-30,共3页
Based on the method of strain mode, damage identification of continuous beam bridges by comparing the variance of several curves of strain modes difference is studied. Three cases of numerical simulation demonstrate t... Based on the method of strain mode, damage identification of continuous beam bridges by comparing the variance of several curves of strain modes difference is studied. Three cases of numerical simulation demonstrate that the proposed method is applicable to detecting many a damage in a continuous beam bridge, which accurately identifies the damaged positions of the bridge, and detects the damage severity of an element by its according peak value of the curve of strain modes difference that is found to increase with the increasing damage severity. 展开更多
关键词 continuous beam bridge DAMAGE DETECT strain mode
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IMAGING ANALYSIS OF FREQUENCY MODULATION CONTINUOUS WAVE SYNTHETIC APERTURE RADAR IN NEAR RANGE MODE
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作者 Yu Zhongjun Xu Zheng Deng Yunkai 《Journal of Electronics(China)》 2014年第1期1-7,共7页
Frequency-Modulation Continuous-Wave Synthetic Aperture Radar(FMCW SAR)has shown great potential in the applications of civil and military fields because of its easy deployment and low cost.However,most of these work ... Frequency-Modulation Continuous-Wave Synthetic Aperture Radar(FMCW SAR)has shown great potential in the applications of civil and military fields because of its easy deployment and low cost.However,most of these work and analysis are concentrated on airborne FMCW SAR,where the characteristics of the imaging geometry and signal are much similar to that of traditional pulsed-SAR.As a result,a series of test campaigns of automobile-based FMCW SAR were sponsored by Institute of Electronics,Chinese Academy of Sciences(IECAS)in the autumn of 2012.In this paper,we analyze the imaging issues of FMCW SAR in automobile mode(named as near range mode),where a vehicle is used as moving platform and a large looking angle is configured.The imaging geometry and signal properties are analyzed in detail.We emphasize the difference of the near range mode from the traditional airborne SAR mode.Based on the analysis,a focusing approach is proposed in the paper to handle the data focusing in the case.Simulation experiment and real data of automobile FMCW SAR are used to validate the analysis. 展开更多
关键词 Frequency-Modulation continuous-Wave(FMCW) Synthetic Aperture Radar(SAR) Automobile-based Near range mode Wave-number domain algorithm
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THE IMPLICIT CONTINUITY OF DISCONTINUOUS SYSTEMS
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作者 陆宇平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期190-194,共5页
An example is presented to introduce the concept of implicit continuity proposed as contrasted with the explicit continuity.A sufficient and necessary condition of the implicit continuity is given and proved in forms ... An example is presented to introduce the concept of implicit continuity proposed as contrasted with the explicit continuity.A sufficient and necessary condition of the implicit continuity is given and proved in forms of implicit system.This condition also offers the solution of initial values at the points where the dynamic system is discontinuous.Some discussions are contributed to the physical significance of implicit continuity. 展开更多
关键词 continuITY initial conditions implicit systems disconitinuous systems impulsive mode
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Development and investigation of electroslag continuous casting 被引量:2
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作者 Ximin Zang Zhouhua Jiang Tieyi Pan 《Journal of University of Science and Technology Beijing》 CSCD 2007年第4期302-306,共5页
The principle and technological design of electroslag continuous casting (ESCC), including bifilar mode, T-shaped mould, and metal level detecting system, are detailed. Remelting was carded out for 1Crl8Ni9Ti stainl... The principle and technological design of electroslag continuous casting (ESCC), including bifilar mode, T-shaped mould, and metal level detecting system, are detailed. Remelting was carded out for 1Crl8Ni9Ti stainless steel with ESCC. The surface finish, chemical composition, macroand microstructures, and inclusions of the remelted billets were characterized. ESCC reduces the cost and increases the productivity in comparison to traditional ESR, while achieves comparably excellent products. 展开更多
关键词 electroslag continuous casting (ESCC) bifilar mode T-shaped mould remelted billets
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Nonlinear continuous bi-inductance electrical line with dissipative elements:Dynamics of the low frequency modulated waves
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作者 S M Ngounou F B Pelap 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期179-189,共11页
The dynamics of modulated waves in a nonlinear bi-inductance transmission line with dissipative elements are examined.We show the existence of two frequency modes and carry out intensive investigations on the low freq... The dynamics of modulated waves in a nonlinear bi-inductance transmission line with dissipative elements are examined.We show the existence of two frequency modes and carry out intensive investigations on the low frequency mode.Thanks to the multiple scales method,the behavior of these waves is investigated and the dissipative effects are analyzed.It appears that the dissipation coefficient increases with the carrier wave frequency.In the continuous approximation,we derive that the propagation of these waves is governed by the complex Ginzburg-Landau equation instead of the Korteweg-de-Vries equation as previously established.Asymptotic studies of the dynamics of plane waves in the line reveal the existence of three additional regions in the dispersion curve where the modulational phenomenon is observed.In the low frequency mode,we demonstrate that the network allows the propagation of dark and bright solitons.Numerical findings are in perfect agreement with the analytical predictions. 展开更多
关键词 DISSIPATIVE bi-inductance network low frequency mode continuous approximation complex GINZBURG-LANDAU equation
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Dynamics of high-frequency modulated waves in a nonlinear dissipative continuous bi-inductance network
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作者 S M Ngounou F B Pelap 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期193-205,共13页
This paper presents intensive investigation of dynamics of high frequency nonlinear modulated excitations in a damped bimodal lattice. The effects of the dissipation are considered through a linear dissipation coeffic... This paper presents intensive investigation of dynamics of high frequency nonlinear modulated excitations in a damped bimodal lattice. The effects of the dissipation are considered through a linear dissipation coefficient whose evolution in terms of the carrier wave frequency is checked. There appears that the dissipation coefficient increases with the carrier wave frequency. In the linear limit and for high frequency waves, study of the asymptotic behavior of plane waves reveals the existence of two additional regions in the dispersion curve where the modulational phenomenon is observed compared to the lossless line. Based on the multiple scales method exploited in the continuum approximation using an appropriate decoupling ansatz for the voltage of the two different cells, it appears that the motion of modulated waves is described by a dissipative complex Ginzburg–Landau equation instead of a Korteweg–de Vries equation. We also show that this amplitude wave equation admits envelope and hole solitons in the high frequency mode. From basic sources, we design a programmable electronic generator of complex signals with desired characteristics, which delivers signals exploited as input waves for all our numerical simulations. These simulations are performed in the LTspice software that uses realistic components and give the results that corroborate perfectly our analytical predictions. 展开更多
关键词 dissipative bi-inductance network high-frequency mode continuous approximation dissipative complex Ginzburg–Landau equation programmable electronic generator LT-Pspice observations
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Reflection and Transmission of the Level Step to the Waves in a Linear and Continuous Layer Liquid
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作者 TAN Xiao-ning LI Qiang 《Journal of China University of Mining and Technology》 EI 2006年第4期448-451,共4页
The reflection and transmission of the level step to the water waves in the linear and continuous layer liquid were studied in this paper. Based on the matching method of the eigenfunction and a Boussinesq approximati... The reflection and transmission of the level step to the water waves in the linear and continuous layer liquid were studied in this paper. Based on the matching method of the eigenfunction and a Boussinesq approximation, the analytical expression of the diffraction was obtained and the computing methods of the reflection and transmission en- ergy of the level step were proposed. For the incident wave with a frequency greater than that of the flotage, there is only one mode of plane traveling wave in the flow field. In the range of this greater frequency, the linear and continuous delamination effect will affect the reflection and transmission energy of the floating rectangular box. When the fre- quency of the incident wave is less than the flotage frequency, the energy of the plane traveling wave with infinite modes in the flow field will change into the energy of different modes for each incident wave of different modes. 展开更多
关键词 continuous linear flow level step internal wave modes reflection energy transmission energy
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基于Quasi-continuous高阶滑模理论的高超声速飞行器控制
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作者 张园园 胡杨 +1 位作者 刘志敏 李仁府 《飞机设计》 2012年第3期1-5,共5页
针对高度非线性、强耦合、参数不确定性的高超声速飞行器数学模型,首先应用精确线性化将其非线性的数学模型转化成符合控制设计要求的等效线性模型,然后引入了Quasi-continuous高阶滑模控制理论,同时采用鲁棒精确微分器来克服测量的困... 针对高度非线性、强耦合、参数不确定性的高超声速飞行器数学模型,首先应用精确线性化将其非线性的数学模型转化成符合控制设计要求的等效线性模型,然后引入了Quasi-continuous高阶滑模控制理论,同时采用鲁棒精确微分器来克服测量的困难。模拟结果表明所设计的控制器对参数不确定性具有很好的鲁棒性,而且达到了期望的性能指标。 展开更多
关键词 高超声速飞行器 Quasi-continuous高阶滑模控制 精确线性化 鲁棒性
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Three-level inverter configuration with common mode voltage elimination for induction motor drive (To continue)
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《变频器世界》 2006年第5期27-28,共2页
The multiplicity of vector combinations for vectors of combined three-level inverters plays an important role, when deciding on the modulation scheme, to obtain minimum switching per inverter vector change, as describ... The multiplicity of vector combinations for vectors of combined three-level inverters plays an important role, when deciding on the modulation scheme, to obtain minimum switching per inverter vector change, as described in the next Section. This is not possible with reduced common-mode three-level inverter structure, obtained with a five-level cascaded H-bridge configuration, as the space vectors locations do not exhibit multiplicity. Moreover, the proposed configuration requires only two power supplies, whereas the scheme with the five-level H-bridge configuration requires six isolated power supplies. 展开更多
关键词 mode To continue Three-level inverter configuration with common mode voltage elimination for induction motor drive
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Web 2.0-Comet-Continuations模式在局部放电实时监测中的应用 被引量:2
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作者 王默玉 刘岩 +2 位作者 刘林 李成榕 王辉 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2009年第1期164-169,共6页
针对传统Web模式的实时系统具有的用户体验不理想、数据延迟高和响应速度慢等缺点,通过对Ajax技术和Web工作模式深入分析研究,采用Web 2.0、Comet、Continuations相结合的方式,结合电缆终端局部放电实时监测系统例证,将三维谱图网格化... 针对传统Web模式的实时系统具有的用户体验不理想、数据延迟高和响应速度慢等缺点,通过对Ajax技术和Web工作模式深入分析研究,采用Web 2.0、Comet、Continuations相结合的方式,结合电缆终端局部放电实时监测系统例证,将三维谱图网格化并结合div技术模拟桌面应用程序局部刷新。该模式下系统具有无闪烁、实时性高的特点,并且即使在连接大量客户端时,服务器也只需消耗较少的CPU和内存资源。 展开更多
关键词 计算机应用 WEB模式 COMET Ajax continuATIONS 实时监测 局部放电
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Improved Method and Application of EMD Endpoint Continuation Processing for Blasting Vibration Signals 被引量:1
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作者 Qing Li Wenlong Xu +2 位作者 Di Zhang Dandan Feng Na Li 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期428-436,共9页
In order to deal with the non-stationary characteristics of blasting vibration signals and the end issue in the empirical mode decomposition(EMD), an improved endpoint continuation method is proposed. First, the linea... In order to deal with the non-stationary characteristics of blasting vibration signals and the end issue in the empirical mode decomposition(EMD), an improved endpoint continuation method is proposed. First, the linear continuation method of extreme points is used to determine the extremum of the signal endpoint fast. Secondly, the extreme points of transition section outside the signal ends are obtained by a mirror continuation method of extreme points, and then the envelope and continuation curve of the transition section of the signal are constructed. Lastly, the sinusoid of the stationary section outside the signal is constructed to achieve the continuation curve from the transition section to the stationary section. Based on the "singular extreme points" phenomenon of blasting vibration signal, the negative maxima and positive minimum are eliminated, then the maximum and minimum are guaranteed to appear at intervals. Thus,the number of iterations is reduced and the instability of EMD decomposition is improved. The calculation formula of amplitude, cycle and initial phase are given for the transition section and stationary section outside the signal. The endpoint processing effect of the simulated signal and the measured blasting vibration signal show that the improved endpoint continuation method can suppress the signal endpoint effect well. 展开更多
关键词 BLASTING vibration signal empirical mode DECOMPOSITION END effect ENDPOINT continuATION
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L2 Syntactic Alignment in the Reading-Writing Integrated Continuation Task: Evidence From Chinese EFL Learners’ Description of Motion Events 被引量:7
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作者 Min WANG Qiao GAN Julie BOLAND 《Chinese Journal of Applied Linguistics》 2021年第3期292-313,430,共23页
This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construct... This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity. 展开更多
关键词 reading-writing integrated continuation task syntactic alignment task mode interactive intensity motion event construction with manner verbs L2 learning
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Stabilization of CSTR w ith Self-tuning Sliding Mode Controller Using T-S Fuzzy Linearization 被引量:2
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作者 朱群雄 王军霞 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期287-292,共6页
A self-tuning reaching law based sliding mode control(SMC)theory is proposed to stabilize the nonlinear continuous stirred tank reactor(CSTR).T-S fuzzy logic is used to build a global fuzzy state-space linear model.Co... A self-tuning reaching law based sliding mode control(SMC)theory is proposed to stabilize the nonlinear continuous stirred tank reactor(CSTR).T-S fuzzy logic is used to build a global fuzzy state-space linear model.Combing the traits of SMC and CSTR,three fuzzy rules can meet the requirements of controlled system.The self-tuning switch control law which can drive the state variables to the sliding surface as soon as possible is designed to ensure the robustness of uncertain fuzzy system.Lyapunov equation is applied to proving the stability of the sliding surface.The simulations show that the proposed approach can achieve desired performance with less chattering problem. 展开更多
关键词 sliding mode control(SMC) continuous stirred tank reactor (STR) T-S fuzzy model self-tuning switch control lawCLC number:TP13Document code:AArticle ID:1672-5220(2013)04-0287-06
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Quasinormal modes of a stationary axisymmetric EMDA black hole
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作者 潘启沅 荆继良 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期77-82,共6页
The massless scalar quasiaormal modes (QNMs) of a stationary axisymmetric Einstein-Maxwell dilato-axioa (EMDA) black hole are calculated numerically using the continued fraction method first proposed by Leaver. Th... The massless scalar quasiaormal modes (QNMs) of a stationary axisymmetric Einstein-Maxwell dilato-axioa (EMDA) black hole are calculated numerically using the continued fraction method first proposed by Leaver. The fundamental quasinormal frequencies (slowly damped QNMs) are obtained and the peculiar behaviours of them are studied. It is shown that these frequencies depend on the dilaton parameter D, the rotational parameter a, the multiple moment l and the azimuthal number m, and have the same values with other authors at the Schwarzschild and Kerr limit. 展开更多
关键词 Quasinormal modes (QNMs) the stationary axisymmetric EMDA black hole the continued fraction method QNMs
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