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Validity Consideration in Designing an Oral English Test
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作者 崔丹 朱殿勇 王庆忠 《海外英语》 2014年第15期105-106,共2页
To make oral test accurately reflect the actual English spoken ability of candidates and play its role in guiding and promoting the improvement of English learners in the teaching, we must ensure that the design of sc... To make oral test accurately reflect the actual English spoken ability of candidates and play its role in guiding and promoting the improvement of English learners in the teaching, we must ensure that the design of scientific questions, the feasibility and validity of judgments to make an accurate and fair measurement of testers' language ability. 展开更多
关键词 Validity considerATION ORAL ENGLISH TEST ENGLISH s
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Validity Considerations in Designing an Oral English Test
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作者 曾小珊 《海外英语》 2012年第15期136-137,共2页
Speaking is the main purpose and most important skill for second language learning.This paper reviews the important validity considerations in designing a test,such as face validity,content validity,on the basis of wh... Speaking is the main purpose and most important skill for second language learning.This paper reviews the important validity considerations in designing a test,such as face validity,content validity,on the basis of which the author analyzes the oral test paper for the postgraduate entrance interview in Shaanxi University of Technology,thus putting forward some methods to improve the test paper. 展开更多
关键词 LANGUAGE TEST validity considerations ORAL ENGLISH
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Vibration analysis of hard-coated composite beam considering the strain dependent characteristic of coating material 被引量:9
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作者 W.Sun Y.Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第4期731-742,共12页
The strain dependent characteristics of hard coatings make the vibration analysis of hard-coated composite structure become a challenging task. In this study, the modeling and the analysis method of a hard-coated comp... The strain dependent characteristics of hard coatings make the vibration analysis of hard-coated composite structure become a challenging task. In this study, the modeling and the analysis method of a hard-coated composite beam was developed considering the strain dependent characteristics of coating material. Firstly, based on analyzing the properties of hard-coating material, a high order polynomial was adopted to characterize the strain dependent characteristics of coating materials. Then, the analytical model of a hard-coated composite beam was created by the energy method. Next, using the numerical method to solve the vibration response and the resonance frequencies of the composite beam, a specific calculation flow was also proposed. Finally,a cantilever beam coated with Mg O + Al2_O_3 hard coating was chosen as the study case; under different excitation levels, the resonance region responses and the resonance frequencies of the composite beam were calculated using the proposed method. The calculation results were compared with the experiment and the linear calculation, and the correctness of the created model was verified. The study shows that compared with the general linear calculation, the proposed method can still maintain an acceptable precision when the excitation level is larger. 展开更多
关键词 coated excitation modulus verified challenging characterize created considering acceptable polynomial
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An adjustment method for active reflector of large high-frequency antennas considering gain and boresight 被引量:7
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作者 Cong-Si Wang Lan Xiao +6 位作者 Wei Wang Qian Xu Bin-Bin Xiang Jian-Feng Zhong Li Jiang Hong Bao Na Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第5期39-50,共12页
The design of the Qitai 110 m Radio Telescope(QTT) with large aperture and very high working frequency(115 GHz) was investigated in Xinjiang, China. The results lead to a main reflector with high surface precision... The design of the Qitai 110 m Radio Telescope(QTT) with large aperture and very high working frequency(115 GHz) was investigated in Xinjiang, China. The results lead to a main reflector with high surface precision and high pointing precision. In this paper, the properties of active surface adjustment in a deformed parabolic reflector antenna are analyzed. To assure the performance of large reflector antennas such as gain and boresight, which can be obtained by utilizing an electromechanical coupling model, and satisfy them simultaneously, research on active surface adjustment applied to a new parabolic reflector as target surface has been done. Based on the initial position of actuators and the relationship between adjustment points and target points, a novel mathematical model and a program thatdirectly calculates the movements of actuators have been developed for guiding the active surface adjustment of large reflector antennas. This adjustment method is applied to an 8 m reflector antenna,in which we only consider gravity deformation. The results show that this method is more efficient in adjusting the surface and improving the working performance. 展开更多
关键词 adjustment reflector antenna pointing deformed utilizing gravity adjusting considering guiding
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A three-equation transition model with mechanical considerations 被引量:1
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作者 Tianxin ZHANG Jianqiang CHEN +2 位作者 Yatian ZHAO Zaijie LIU Chao YAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期178-190,共13页
A three-equation transition model based on the transition V-model is proposed for subsonic flows in this study. Considering the mechanical approximation of the generation process of the pre-transitional vorticities, t... A three-equation transition model based on the transition V-model is proposed for subsonic flows in this study. Considering the mechanical approximation of the generation process of the pre-transitional vorticities, the value of laminar Reynolds shear stress related to the mean shear deformation was calculated in the original transition V-model. Then a new transition model, named V-SA model, was proposed, which considered the phenomenological process of transition and presented great results for flows with and without pressure gradient. It is well-known that the baseline Shear Stress Transport(SST) turbulence model shows excellent performance of accuracy and robustness in plentiful flow cases, but it is important to predict boundary layer transition. The current model(V-SST) successfully couples the V-model to the SST turbulence model by introducing the effective turbulent viscosity and additional correction terms into the transport equations. A thorough evaluation of its ability to predict transition features is performed versus the well-documented flat plate of ERCOFTAC, including T3A and T3B without pressure gradient, T3L2 and T3L3 with semi-circular leading edge, the three-dimensional 6:1 prolate-spheroid under two angles of attack, and the NLR-7301 airfoil under different Mach numbers. Numerical results show that the current model has an attractive and superior performance in the simulation of boundary layer transition processes. 展开更多
关键词 Laminar kinetic energy Mechanical consideration Shear stress transport turbulence model Transition model V-model
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Management considerations following overdoses of modified-release morphine preparations 被引量:1
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作者 Jamie L. Nelsen Jeanna M. Marraffa +1 位作者 Landon Jones William D. Grant 《World Journal of Emergency Medicine》 SCIE CAS 2010年第1期75-76,共2页
Analgesics have consistently remained the most common substance involved in human poisonings in the United States, with immediate action opioid analgesics associated with the greatest percent of fatalities per exposure.
关键词 Management considerations morphine preparations
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A Consideration on Listening Teaching to College English
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作者 黎源 宋振华 《科教导刊》 2015年第10Z期120-121,共2页
本文通过介绍听力过程以及当今听力教学的三大模式,针对当今听力教学现状,结合作者的教学实际,提出作者对听力教学的几点思考。
关键词 LISTENING TEACHING MODEL considerATION
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Numerical simulation and transonic wind-tunnel test for elastic thin-shell structure considering fluid–structure interaction 被引量:1
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作者 Yan Yunju Xi Zhuyou Zhang Shanzhi 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第1期141-151,共11页
Aerodynamic force can lead to the strong structural vibration of flying aircraft at a high speed. This harmful vibration can bring damage or failure to the electronic equipment fixed in aircraft. It is necessary to pr... Aerodynamic force can lead to the strong structural vibration of flying aircraft at a high speed. This harmful vibration can bring damage or failure to the electronic equipment fixed in aircraft. It is necessary to predict the structural dynamic response in the design course. This paper presents a new numerical algorithm and scheme to solve the structural dynamics responses when considering fluid–structure interaction(FSI). Numerical simulation for a free-flying structural model in transonic speed is completed. Results show that the small elastic deformation of the structure can greatly affect the FSI. The FSI vibration tests are carried out in a transonic speed windtunnel for checking numerical theory and algorithms, and the wind-tunnel test results well accord with that of the numerical simulation. This indicates that the presented numerical method can be applied to predicting the structural dynamics responses when containing the FSI. 展开更多
关键词 considering tunnel checking aircraft meshes flying completed rigid acceleration harmful
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New method for oblique impact dynamics research of a flexible beam with large overall motion considering impact friction force 被引量:1
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作者 W.Yuan L.Li +1 位作者 D.G.Zhang J.Z.Hong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第4期720-730,共11页
A flexible beam with large overall rotating motion impacting with a rigid slope is studied in this paper. The tangential friction force caused by the oblique impact is analyzed. The tangential motion of the system is ... A flexible beam with large overall rotating motion impacting with a rigid slope is studied in this paper. The tangential friction force caused by the oblique impact is analyzed. The tangential motion of the system is divided into a stick state and a slip state. The contact constraint model and Coulomb friction model are used respectively to deal with the two states. Based on this hybrid modeling method, dynamic equations of the system, which include all states(before, during, and after the collision)are obtained. Simulation results of a concrete example are compared with the results obtained from two other models: a nontangential friction model and a modified Coulomb model. Differences in the results from the three models are discussed. The tangential friction force cannot be ignored when an oblique impact occurs. In addition, the results obtained from the model proposed in this paper are more consistent with real movement. 展开更多
关键词 collision oblique friction stick tangential considering Coulomb constraint coordinate rotating
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Strategic Considerations on Development of WiMAX and Its Relationship with 3G and 4G 被引量:1
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作者 Chen Ruming (Communications Science and Technology Commission, Ministry of Information Industry, Beijing 100037, China) 《ZTE Communications》 2005年第1期48-50,53,共4页
The paper states the characteristics and basic market positioning of WiMAX. It should be noted that WiMax is a new generation WMAN (Wideband MAN) broadband wireless access standard with good forward extensibility. It ... The paper states the characteristics and basic market positioning of WiMAX. It should be noted that WiMax is a new generation WMAN (Wideband MAN) broadband wireless access standard with good forward extensibility. It is emphasized that the basic market positioning of WiMAX should be nothing but WMAN applications. It is predicted that the applications of WiMax would face severe challenges mainly due to its high cost, at least at the initial stage. Finally the paper gives all-around analysis on the relationship between Wi-Fi, WiMAX, WBMA, 3G, 3G+ and 4G. 展开更多
关键词 WIMAX rate Strategic considerations on Development of WiMAX and Its Relationship with 3G and 4G
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Robust Optimization Operation of Power System Considering the Non-probabilistic Uncertainty of Parameter 被引量:1
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作者 李雪 何震晨 杜大军 《Journal of Donghua University(English Edition)》 EI CAS 2016年第5期708-712,共5页
Probabilistic method requires a lot of sample information to describe the probability distributions of uncertain variables and has difficulty in dealing with the optimization problem with uncertain parameters which co... Probabilistic method requires a lot of sample information to describe the probability distributions of uncertain variables and has difficulty in dealing with the optimization problem with uncertain parameters which contains unsufficient information.To solve this problem,a robust optimization operation method based on information gap decision theory(IGDT) is presented considering the non-probabilistic uncertainties of parameters.By the proposed method the maximum resistance to the disturbance of uncertain parameters is achieved and the optimization strategies with uncertain parameters are presented.Finally,numerical simulation is performed on the modified IEEE-14 bus system.Numerical results show the effectiveness of the proposed approach. 展开更多
关键词 probabilistic uncertain disturbance difficulty dealing Pareto guaranteed guarantees considering constraint
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Review: Hu Houxuan, "Xia and the Tu State in the Oracle Inscriptions: A Consideration" Gudai Chengbang Shi Yanjiu (Studies on Ancient City States) Renmin Press, 1989, Pp. 340-353. 被引量:1
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作者 RiZhi 《Journal of Ancient Civilizations》 1995年第0期147-148,共2页
This article verified that the Tu state mentioned in the oracle inscriptions was the Xia people after the Xia Dynasty had been conquered by Tang, the first king of the Shang Dynasty m c.a. 16th century B.C. The state... This article verified that the Tu state mentioned in the oracle inscriptions was the Xia people after the Xia Dynasty had been conquered by Tang, the first king of the Shang Dynasty m c.a. 16th century B.C. The state of Xia, which originated from Yu, was entitled "Xia Hou"; its king was hence called "Xia Hou Di" (Emperor of Xia Hou), e.g."Xia Hou Di Qi". The Xia people, together with the Yin (Shang) people, and the Zhou people, were the so-called "people of San Dai" (Three Dynasties). As mentioned in "Lunyu, Bayi", they founded the states, with the Xia people being associated with the pine, the Yin people with the cypress, and the Zhou people with the chestnut. 展开更多
关键词 A consideration Renmin Press Studies on Ancient City States Xia and the Tu State in the Oracle Inscriptions Hu Houxuan Gudai Chengbang Shi Yanjiu
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谈谈consider
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作者 刘德文 《中学英语园地(高三版)》 2000年第10期18-19,共2页
关键词 consider 高中 英语 词义 用法
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consider用法透视
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作者 王振强 《英语通(高二版)》 2004年第4期10-10,共1页
在SEFC Book Ⅱ B Lesson 79中有这样一个句子:“Some people have the wrong attitude towards people with disabilities,considering them to be stupid.”“有些有对待残疾人的态度不好,认为他们愚蠢。”句中的consider后面跟着... 在SEFC Book Ⅱ B Lesson 79中有这样一个句子:“Some people have the wrong attitude towards people with disabilities,considering them to be stupid.”“有些有对待残疾人的态度不好,认为他们愚蠢。”句中的consider后面跟着一个带有动词不定式的复合结构, 展开更多
关键词 consider 用法 动词不定式 高中 英语
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Local Optimization and Adversarial Consideration: Agent Skills in Everest Simulation Team
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作者 顾洋 崔立辉 +1 位作者 刘俊峰 王庆林 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期34-38,共5页
Skilled individual agents are firm basis of a strong soccer team. The skills available to Everest 2002 (agents) include kicking, dribbling, forwarding, ball interception and tackling. These intermediate sub goals are ... Skilled individual agents are firm basis of a strong soccer team. The skills available to Everest 2002 (agents) include kicking, dribbling, forwarding, ball interception and tackling. These intermediate sub goals are implemented by a combination of local optimization which hopes to determine the optimal primitive action from a local perspective and adversarial consideration which takes into account opponents and limitations imposed by simulation environment. Everest 2002 RoboCup simulation teams, building on 11 skilled agents and an on-line coach, won the 2nd place in RoboCup 2002 simulation league. 展开更多
关键词 local optimization and adversarial consideration (LOAC) AGENT SKILL ROBOCUP
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Neuroprotection and recovery from early-life adversity: considerations for environmental enrichment
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作者 Amanda C.Kentner 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第10期1545-1547,共3页
In the laboratory,environmental enrichment(EE)is used as a protocol to understand the functional,behavioral and molecular mechanisms that underlie neural plasticity(van Praag et al.,2000;Sale et al.,2014).In addit... In the laboratory,environmental enrichment(EE)is used as a protocol to understand the functional,behavioral and molecular mechanisms that underlie neural plasticity(van Praag et al.,2000;Sale et al.,2014).In addition,it is utilized to provide supplementary resources to animals in order to maintain their well-being and to preserve the scientific validity of the study at hand(see http://www.nap.edu/catalog/12910/guide-for-thecare-and-use-of-laboratory-animals-eighth). 展开更多
关键词 LIFE Neuroprotection and recovery from early-life adversity considerations for environmental enrichment EE
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A New Simulation of Track Structure of Low-Energy Electrons in Liquid Water:Considering the Condensed-Phase Effect on Electron Elastic Scattering
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作者 刘玮 谭震宇 C.Champion 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期35-38,共4页
A new Monte Carlo simulation of the track structure of low-energy electrons (〈10keV) in liquid water is presented. The feature of the simulation is taken into consideration of the condensed-phase effect of liquid w... A new Monte Carlo simulation of the track structure of low-energy electrons (〈10keV) in liquid water is presented. The feature of the simulation is taken into consideration of the condensed-phase effect of liquid water on electron elastic scattering with the use of the Champion model, while the dielectric response formalism incorporating the optical-data model developed by Emfietzoglou et al. is applied for calculating the electron inelastic scattering. The spatial distributions of energy deposition and inelastic scattering events of low-energy electrons with different primary energies in liquid water are calculated and compared with other theoretical evaluations. The present work shows that the condensed-phase effect of liquid water on electron elastic scattering may be of the influence on the fraction of absorbed energy and distribution of inelastic scattering events at lower primary energies, which also indicate potential effects on the DNA damage induced by low-energy electrons. 展开更多
关键词 of as in A New Simulation of Track Structure of Low-Energy Electrons in Liquid Water:considering the Condensed-Phase Effect on Electron Elastic Scattering for CCPI on is
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Study on Low Hilly Cities Land Suitability Evaluation Method Based on Ecological Considerations—A Case Study of Longfeng New Town in Sichuan
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作者 Bin Cheng Haifeng Lan Weiwei Wu 《Journal of Building Construction and Planning Research》 2018年第2期41-51,共11页
Attention to the development of low hilly cities increases, in order to guide their development towards efficient and ecological land use. This paper takes eco-safety into consideration in the future layout of land fo... Attention to the development of low hilly cities increases, in order to guide their development towards efficient and ecological land use. This paper takes eco-safety into consideration in the future layout of land for construction, and incorporates ecological security factors into traditional methods of land suitability evaluation based on topographic conditions. Taking the Longfeng New Town in Suining City as an example, the GIS platform is used to superimpose various evaluation factors. The evaluation index system is determined using the combination of the Delphi Technique and AHP. The result of correcting traditional land suitability evaluation is obtained, which provides decision support for improving the scientificity of land use planning and layout. 展开更多
关键词 ECOLOGICAL considerations Urban Land Use SUITABILITY Evaluation GIS (Geographic Information System)
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An Adjusted Model for Simple 1,2-Dyotropic Reactions. <i>Ab Initio</i>MO and VB Considerations
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作者 Henk M. Buck 《Open Journal of Physical Chemistry》 2013年第3期119-125,共7页
With an adjusted model, we reconsider simple 1,2-dyotropic reactions with the introduction of a concept based on the intramolecular dynamics of a tetrahedron (van ’t Hoff modeling). In fact the dyotropic reactions ar... With an adjusted model, we reconsider simple 1,2-dyotropic reactions with the introduction of a concept based on the intramolecular dynamics of a tetrahedron (van ’t Hoff modeling). In fact the dyotropic reactions are strongly related to conversions originated from neighbouring group participation or anchimeric assistance, defined as the interaction of a center with a lone pair of electrons in an atom and the electrons present in aδor π bond. The researchful 1,2-dyotropic reactions, based on the 1,2-interchange of halogens, methyl and hydrogen taking place in a concerted fashion, are in competition with the two-step reaction in which the neighbouring group participation or anchimeric assistance comes to full expression by ionic dissociation of the other exchangeable (halogen) atom. As to be expected there is an essential difference between halogen or methyl exchange regarding the number of electrons participating in the transition state. This aspect becomes evident in the geometries of the corresponding transition state geometries. In this paper we refer to ab initio MO calculations and VB considerations. We consider the 1,2-halogen exchange as a combination of two SN2 reactions each containing four electrons. The van ’t Hoff dynamics appears a useful model in order to illustrate the computations in a straightforward manner. 展开更多
关键词 Type-I Dyotropic REACTIONS MO Calculations Van ’t HOFF MODEL considerations Halogen and Methyl Exchange Conflicting Models
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Mobility of Various Intervariant Interfaces in 18R Martensitein a Cu-Zn-Al AlloyPart Ⅱ: Some Theoretical Considerations
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作者 Jianxin ZHANG Yufeng ZHENG Wei CAI and Liancheng ZHAO (School of Materials Science and Engineering, Harbin Institute of Technology Harbin, 150001, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1998年第4期349-352,共4页
Detailed crystallographic analysis has been undertaken on the various combinations Of 24 martensite variants in the 18R martensite of a Cu-Zn-Al shape memory alloy. Based upon the calculated crystallographic data, the... Detailed crystallographic analysis has been undertaken on the various combinations Of 24 martensite variants in the 18R martensite of a Cu-Zn-Al shape memory alloy. Based upon the calculated crystallographic data, the interface energy of different twin interfaces was calculated using a lowangle-grain-interface model. For the variant/variant pairs in a self-accommodating group. the A/C type and A/B type interfaces have low interface energy, and A/D type interface is an intermediate one. In contrast, the intervariant interfaces that belong to different plate groups have high intrface energy. The calculated results are consiStent with the previous observations of the mobility of intervariant interfaces. 展开更多
关键词 ZN Al Mobility of Various Intervariant Interfaces in 18R Martensitein a Cu-Zn-Al AlloyPart Some Theoretical considerations Cu
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