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陈士元《俗用杂字》中的应城方言词 被引量:1
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作者 邵则遂 《语言研究》 CSSCI 北大核心 2008年第4期89-93,共5页
陈士元的《俗用杂字》记录了明代湖北应城310条方言词,反映了当时各词的语义和部分词的读音。
关键词 俗用杂 城方言
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一个“应”字不简单
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作者 本刊编辑部 《中国应急管理》 2018年第7期1-1,共1页
“七下八上”,主汛期、暑期,小到个人出行道路的选择,大到一个区域、流域的工业生产、居民生活,乃至人的生命财产安全,汛情、灾害无情地考验着人们的应对能力。
关键词 “应”字 生命财产安全 工业生产 居民生活
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《明本大字应用碎金》农桑类名词考释六则
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作者 刘昌昊 《辽东学院学报(社会科学版)》 2019年第6期91-96,共6页
《明本大字应用碎金》是明代最早的日用类书,是研究元末明初民间日用类名物词的重要资料。文章对"蚕■"等六例疑难农桑名词进行了考释。
关键词 《明本大用碎金》 农桑名词 蚕■ 舂杵
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A 1×4 Polymeric Digital Optical Switch Based on the Thermo-Optic Effect 被引量:1
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作者 唐奕 张昊 +2 位作者 杨建义 王明华 江晓清 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期692-695,共4页
We present a 1 × 4 Y-branch digital optical switch in which S-bend variable optical attenuators are integrated. The S-bend waveguides, which are always introduced to connect the switch and the standard fiber arra... We present a 1 × 4 Y-branch digital optical switch in which S-bend variable optical attenuators are integrated. The S-bend waveguides, which are always introduced to connect the switch and the standard fiber array, are made use of and designed as variable optical attenuators. A compact device with low crosstalk and larger branching-angle is obtained. The device is fabricated on the thermo-optic polymer materials,and the performance of the device is measured. With an applied driving power of less than 200mW, the device has a low crosstalk of less than - 35dB at a wavelength of 1.55 μm. 展开更多
关键词 bend waveguide variable optical attenuator thermo-optic effect digital optical switch integrated optics
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Applicahon of a Simplified Model Reference Adaptive Algorithm 被引量:1
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作者 王丽艳 宫小东 +1 位作者 金志立 曹泛 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期90+82-90,共10页
The application of a simplifed model reference adaptive control(SMRAC) on a typical Pump controlled motor electrohydraulic servo system is studied here. The algorithm of first-order scalar SMRAC ac second-order vector... The application of a simplifed model reference adaptive control(SMRAC) on a typical Pump controlled motor electrohydraulic servo system is studied here. The algorithm of first-order scalar SMRAC ac second-order vector SMRAC are derived. Computer simulations of the algorithms are presented. Experimental results prove that the method of control adopted here perform satisfactorily over a wide range of operating conditions. 展开更多
关键词 model reference adaptive control digital control electrohydraulic servo system
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Design and Development of the DTC Induction Motor Drive for Electric Vehicle
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作者 孙逢春 程夕明 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期415-421,共7页
The design and development of the traction controller for electric vehicle is introduced, which is based on the induction motor. This drive is developed by using a digital signal processor at low cost and carried out ... The design and development of the traction controller for electric vehicle is introduced, which is based on the induction motor. This drive is developed by using a digital signal processor at low cost and carried out with the module design concept of both software and hardware. Nevertheless, a scheme of the sensorless direct torque control is based on the developed hardware, of which the feasibility is tested by a trial program. Additionally, both the interface function of the drive hardware and the feasibility of its software are proved to be good by the trail programs. A test motor can run about 18?r/min by a variable frequency program with the space vector pulse width modulation technology, of which the torque is visible pulsatile. In this presentation, based on the theoretical approach, the sensorless torque control is to be studied and applied to electric vehicles, of which the quick, smooth and stable torque response is emphasized because it quite benefits improving the drive performance of electric vehicles. 展开更多
关键词 electric vehicle induction motor digital signal processor direct torque control
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Mesh Size Effect in Numerical Simulation of Blast Wave Propagation and Interaction with Structures 被引量:25
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作者 师燕超 李忠献 郝洪 《Transactions of Tianjin University》 EI CAS 2008年第6期396-402,共7页
Numerical method is popular in analysing the blast wave propagation and interaction with structures.However,because of the extremely short duration of blast wave and energy trans-mission between different grids,the nu... Numerical method is popular in analysing the blast wave propagation and interaction with structures.However,because of the extremely short duration of blast wave and energy trans-mission between different grids,the numerical results are sensitive to the finite element mesh size.Previous numerical simulations show that a mesh size acceptable to one blast scenario might not be proper for another case,even though the difference between the two scenarios is very small,indicating a simple numerical mesh size convergence test might not be enough to guarantee accu-rate numerical results.Therefore,both coarse mesh and fine mesh were used in different blast scenarios to investigate the mesh size effect on numerical results of blast wave propagation and interaction with structures.Based on the numerical results and their comparison with field test re-sults and the design charts in TM5-1300,a numerical modification method was proposed to correct the influence of the mesh size on the simulated results.It can be easily used to improve the accu-racy of the numerical results of blast wave propagation and blast loads on structures. 展开更多
关键词 mesh size effect numerical simulation sensitivity blast wave propagation blast load STRUCTURES
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Numerical Simulation of Spectral Response for 650 nm Silicon Photodetector 被引量:7
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作者 LIU Li-na, CHEN Chao, LIU Cai-hong(Dept.of Phy.,Xiamen University,Xiamen 361005,CHN) 《Semiconductor Photonics and Technology》 CAS 2003年第2期82-88,共7页
The theoretical spectral response formula of the N+-N-I-P+ silicon photodetector with high/low emission junction is given. At the same time, considering the process requirements, the optimum structure parameters of si... The theoretical spectral response formula of the N+-N-I-P+ silicon photodetector with high/low emission junction is given. At the same time, considering the process requirements, the optimum structure parameters of silicon photodetector are obtained by numerical calculation and simulation. Under the condition of these optimum structure parameters, the responsivity of the silicon photodetector will be 0.48 A/W at 650 nm. 展开更多
关键词 spectral response SILICON PHOTODETECTOR
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Influences of Quantum and Disorder Effects on Solitons Excited in Protein Molecules in Improved Model 被引量:1
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作者 PANGXiao-Feng YUJia-Feng LUOYu-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期367-376,共10页
Utilizing the improved model with quasi-coherent two-quantum state and new Hamiltonian containing an additional interaction term [Phys. Rev. E62 (2000) 6989 and Euro. Phys. J. B19 (2001) 297] we study numerically the ... Utilizing the improved model with quasi-coherent two-quantum state and new Hamiltonian containing an additional interaction term [Phys. Rev. E62 (2000) 6989 and Euro. Phys. J. B19 (2001) 297] we study numerically the influences of the quantum and disorder effects including distortion of the sequences of masses of amino acid molecules and fluctuations of force constant of molecular chains, and of exciton-phonon coupled constants and of the dipole-dipole interaction constant and of the ground state energy on the properties of the solitons transported the bio-energy in the protein molecules by Runge-Kutta method. The results obtained show that the new soliton is robust against these structure disorders, especially for stronger disorders in the sequence of masses spring constants and coupling constants,except for quite larger fluctuations of the ground state energy and dipole-dipole interaction constant. This means that the new soliton in the improved model is very stable in normal cases and is possibly a carrier of bio-energy transport in the protein molecules. 展开更多
关键词 bio-energy transport protein SOLITON quantum effect disorder effect numerical simulation
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Numerical simulation of micromixing effect on the reactive flow in a co-rotating twin screw extruder 被引量:5
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作者 Hao Tang Yuan Zong Ling Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1135-1146,共12页
To control the multicomponent reactions in extrusion, reactive-mixing flow in a co-rotating twin screw extruder was numerically studied in the present paper. Effects of initial species distribution, rotating speed and... To control the multicomponent reactions in extrusion, reactive-mixing flow in a co-rotating twin screw extruder was numerically studied in the present paper. Effects of initial species distribution, rotating speed and flow rate on a competitive-parallel reaction were investigated and the relationship between mixing and reactions was discussed from the view of chemical reaction engineering. The simulation results show the studied operational parameters, which determine residence time distribution, earliness of mixing and segregation degree of reactive-mixing flows, affect the local species concentration and reaction time and hence have significant influences on the reaction extent. Orthogonal test was adopted to clarify the significance of operational parameters.The analysis shows that initial species distribution and flow rate are the most important factors in the control of reaction extent, and effect of rotating speed is conditional depending on the micro-mixing status of the fluid. 展开更多
关键词 Multicomponent reaction Mixing Numerical simulation Extrusion
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Numerical simulation of rock deformation during the mineralization of the Xiangshan uranium deposit, Jiangxi province, south China 被引量:3
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作者 ZHOU Ye LIN Ge YANG Li-qiang 《Journal of China University of Mining and Technology》 EI 2008年第3期342-346,共5页
The Xiangshan uranium deposit in Jiangxi province is one of the most important uranium deposits in China. The aim of our study is to obtain a better understanding of rock deformation and dilation associated with miner... The Xiangshan uranium deposit in Jiangxi province is one of the most important uranium deposits in China. The aim of our study is to obtain a better understanding of rock deformation and dilation associated with mineralization, to predict the most favorable locations of mineralization, and to assist with future mineral exploration in this deposit. On the basis of geological and structural data from previous studies, we have constructed a coupled deformation and fluid flow numerical model and simulated the faulting deformation and major mechanical factors controlling mineralization in the deposit. Particular attention has been paid to variations in regional stress, distributions of shear strain, volumetric strain and pore pressure. The relationship between the struc-tural/faulting movement and mineralization is obtained through analyzing the deformation state of fault zones. The results suggest that the mineralization is related to volumetric strain, shear strain and pore pressures. The locations displaying all these factors rep-resent the most favorable sites for mineralization. These model results are important for guiding the exploration of new uranium deposits in Xiangshan. 展开更多
关键词 numerical simulation Xiangshan rock deformation volumetric strain shear strain pore pressure
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A New Browder Fixed Point Theorem in Noncompact Hyperconvex Metric Spaces and Its Applications to Section Questions and Intersection Questions 被引量:3
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作者 WEN Kai-ting 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期112-116,共5页
In this paper, a new Browder fixed point theorem is established in the noncompact sub-admissible subsets of noncompact hyperconvex metric spaces. As application, a Ky Fan section theorem and an intersection theorem ar... In this paper, a new Browder fixed point theorem is established in the noncompact sub-admissible subsets of noncompact hyperconvex metric spaces. As application, a Ky Fan section theorem and an intersection theorem are obtained. 展开更多
关键词 hyperconvex metric space fixed point sub-admissible set noncompact measure SECTION INTERSECTION
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AN ITERATIVE ALGORITHM FOR OPTIMAL DESIGN OF NON-FREQUENCY-SELECTIVE FIR DIGITAL FILTERS 被引量:1
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作者 Tian Xinguang Duan Miyi +1 位作者 Sun Chunlai Liu Xin 《Journal of Electronics(China)》 2008年第5期667-672,共6页
This paper proposes a novel iterative algorithm for optimal design of non-frequency-selective Finite Impulse Response(FIR) digital filters based on the windowing method.Different from the traditional optimization conc... This paper proposes a novel iterative algorithm for optimal design of non-frequency-selective Finite Impulse Response(FIR) digital filters based on the windowing method.Different from the traditional optimization concept of adjusting the window or the filter order in the windowing design of an FIR digital filter,the key idea of the algorithm is minimizing the approximation error by succes-sively modifying the design result through an iterative procedure under the condition of a fixed window length.In the iterative procedure,the known deviation of the designed frequency response in each iteration from the ideal frequency response is used as a reference for the next iteration.Because the approximation error can be specified variably,the algorithm is applicable for the design of FIR digital filters with different technical requirements in the frequency domain.A design example is employed to illustrate the efficiency of the algorithm. 展开更多
关键词 Finite Impulse Response (FIR) digital filters Optimal design Windowing method Approximation error Iterative algorithm
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Industrial shape detecting system of cold rolling strip 被引量:9
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作者 杨利坡 于丙强 +1 位作者 丁栋 刘宏民 《Journal of Central South University》 SCIE EI CAS 2012年第4期994-1001,共8页
A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing (DSP... A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing (DSP) shape signal processing board and the shape control model. Based on the shape detecting principle, the shape detecting roller is designed with a new integral structure for improving the precision of shape detecting and avoiding scratching strip surface. Based on the DSP technology, the DSP shape signal processing circuit board is designed and embedded in the shape detecting system for the reliability and stability of shape signal processing. The shape detecting system was successfully used in Angang 1 250 mm HC 6-high reversible cold rolling mill. The precision of shape detecting is 0.2 I and the shape deviation is controlled within 6 1 after the close loop shape control is input. 展开更多
关键词 shape detecting digital signal processing (DSP) shape signal processing close loop shape control cold rolling strip
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Analysis and design of DSP-based dual-loop controlled UPS inverters 被引量:2
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作者 吴燮华 言超 《Journal of Zhejiang University Science》 EI CSCD 2003年第3期276-280,共5页
This paper presents a novel digital dual-loop control scheme of the PWM(PUlse width modulate)inverter. Deadbeat control technique are employed to enhance the performance. Half switching period delayed sampling and con... This paper presents a novel digital dual-loop control scheme of the PWM(PUlse width modulate)inverter. Deadbeat control technique are employed to enhance the performance. Half switching period delayed sampling and control timing strategy is used to improve the system dynamic response. Simulation and experimental results presented in the paper verified the validity of the proposed control scheme. 展开更多
关键词 Digital control Inductor current mode Dual loop
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Stress Concentration Factors at Saddle and Crown Positions on the Central Brace of Two-Planar Welded CHS DKT-connections 被引量:2
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作者 Hamid Ahmadi Mohammad Ali Lotfollahi-Yaghin Mohammad H. Aminfar 《Journal of Marine Science and Application》 2012年第1期83-97,共15页
A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions. The analysis results were used to present general remarks on the effects of the geometric... A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions. The analysis results were used to present general remarks on the effects of the geometrical parameters on stress concentration factors (SCFs) at the inner saddle, outer saddle, and crown positions on the central brace. Based on results of finite element (FE) analysis and through nonlinear regression analysis, a new set of SCF parametric equations was established for fatigue design purposes. An assessment study of equations was conducted against the experimental data and original SCF database. The satisfaction of acceptance criteria proposed by the UK Department of Energy (UK DoE) was also checked. Results of parametric study showed that highly remarkable differences exist between the SCF values in a multi-planar DKT-joint and the corresponding SCFs in an equivalent uni-planar KT-joint having the same geometrical properties. It can be clearly concluded from this observation that using the equations proposed for uni-planar KT-connections to compute the SCFs in multi-planar DKT-joints will lead to either considerably under-predicting or over-predicting results. Hence, it is necessary to develop SCF formulae specially designed for multi-planar DKT-joints. Good results of equation assessment according to UK DoE acceptance criteria, high values of correlation coefficients, and the satisfactory agreement between the predictions of the proposed equations and the experimental data guarantee the accuracy of the equations. Therefore, the developed equations can be reliably used for fatigue design of offshore structures. 展开更多
关键词 offshore jacket structure multi-planar tubular DKT-joint fatigue hot-spot stress method stressconcentration factor (SCF)
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Search for New Three-, Four-Component Petasis, Passerini, Hantzsch, Kabachnic-Fields, Ugi Reactions with Organic Compounds of Phosphorus, Arsenic, Antimony and Bismuth
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作者 Aibassov Erkin Zhakenovich Yemelyanova Valentina Stepanovna Shakieva Tatyana Vladimirovna TussupbaevNessipbay Kuandykovich Blagikh Evgeniy Vladimirovich 《Journal of Chemistry and Chemical Engineering》 2014年第4期428-432,共5页
It is discovered a new three-, four-component Petasis, Passerini, Hantzsch, Kabachnic-Fields, Ugi reactions with of arsine, stibine and bismuthine in organometallic chemistry. Modifications were replaced to a nitrogen... It is discovered a new three-, four-component Petasis, Passerini, Hantzsch, Kabachnic-Fields, Ugi reactions with of arsine, stibine and bismuthine in organometallic chemistry. Modifications were replaced to a nitrogen atom of classical reactions of atoms of phosphorus, arsenic, antimony and bismuth. It has been proposed a new mechanism for possible reactions. 展开更多
关键词 Petasis Passerini HANTZSCH Kabachnic-Fields Ugi reactions PHOSPHORUS ARSENIC ANTIMONY bismuth.
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Four optimal design approaches of high-order finite-impulse response filters based on neural network
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作者 王小华 何怡刚 刘美容 《Journal of Central South University of Technology》 EI 2007年第1期94-99,共6页
Four optimal approaches of high-order finite-impulse response(FIR) digital filters were developed for designing four types filters using neural network algorithms. The solutions were presented as parallel algorithms t... Four optimal approaches of high-order finite-impulse response(FIR) digital filters were developed for designing four types filters using neural network algorithms. The solutions were presented as parallel algorithms to approximate the desired frequency response specification. Therefore, these methods avoid matrix inversion, and make a fast calculation of the filter’s coefficients possible. The convergence theorems of these proposed algorithms were presented and proved to illustrate them stable, and the implementation of these methods was described together with some design guidelines. The simulation results show that the ripples of the designed FIR filters are significantly little in the pass-band and stop-band, and the proposed algorithms are of fast convergence. 展开更多
关键词 high-order finite-impulse response digital filter frequency response neural network convergence theorem
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Numerical Simulation of the Flat Ribbon Wound Explosion Containment Vessels Subjected to Internal Blast Loading
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作者 SONG Yanze LI Zhiqiang +1 位作者 ZHAO Longmao ZHENG Jinyang 《Transactions of Tianjin University》 EI CAS 2006年第B09期223-227,共5页
In order to constitute engineering design methods of the flat ribbon wound explosion containment vessels, the dynamic response of such vessels subjected to internal explosion loading is simulated using LS-DYNA3D. Thre... In order to constitute engineering design methods of the flat ribbon wound explosion containment vessels, the dynamic response of such vessels subjected to internal explosion loading is simulated using LS-DYNA3D. Three winding angles, 10°, 15°and 20°, are considered. It is shown that among ribbon vessels investigated, the center displacement of outermost ribbons of the vessel with 10°winding angle is the smallest under the same blast loading. The response of vessels loaded in inner core is local. From the center of the cylindrical shell to the bottom cover, the maximum strain gradually decreases. The ribbons are subjected to tension in the length direction and compression in the width direction. Blasting shock energy concentrates on where is close to center section of blasting. For comparison, numerical simulation of a monobloc thick-walled explosion containment vessel is also investigated. It can be found that the biggest deformation of the flat ribbon wound explosion containment vessels is bigger than that of the monobloc thick-walled explosion containment vessel in the center section of blasting under the same TNT. Numerical results are approximately in agreement with experimental ones. It is proved that the ribbon vessels have the valuable properties of ' leak before burst at worst' compared with the monobloc vessels through numerical simulation. 展开更多
关键词 flat ribbon wound explosion containment vessels blast loading dynamic response numerical simulation
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AN ALGORITHM FOR DICTIONARY GENERATION IN SPARSE REPRESENTATION
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作者 Xie Zongbo Feng Jiuchao 《Journal of Electronics(China)》 2009年第6期836-841,共6页
The K-COD (K-Complete Orthogonal Decomposition) algorithm for generating adaptive dictionary for signals sparse representation in the framework of K-means clustering is proposed in this paper,in which rank one approxi... The K-COD (K-Complete Orthogonal Decomposition) algorithm for generating adaptive dictionary for signals sparse representation in the framework of K-means clustering is proposed in this paper,in which rank one approximation for components assembling signals based on COD and K-means clustering based on chaotic random search are well utilized. The results of synthetic test and empirical experiment for the real data show that the proposed algorithm outperforms recently reported alternatives: K-Singular Value Decomposition (K-SVD) algorithm and Method of Optimal Directions (MOD) algorithm. 展开更多
关键词 Sparse representation K-Complete Orthogonal Decomposition (K-COD) Adaptivedictionary
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