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Reflections on the theoretical basis and teaching practice of TPR teaching method 预览
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作者 王悦琦 《校园英语》 2019年第32期57-58,共2页
This essay explains TPR language teaching method from different aspects.It also gives some advice on helping foreign language teachers in understanding and applying TPR to the practical teaching.Meanwhile,the paper al... This essay explains TPR language teaching method from different aspects.It also gives some advice on helping foreign language teachers in understanding and applying TPR to the practical teaching.Meanwhile,the paper also gives some suggestions about how to use TPR in China. 展开更多
关键词 THEORETICAL BASE TPR ACQUISITION
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Theoretical modeling and experimental verifications of the single-compressor-driven three-stage Stirling-type pulse tube cryocooler
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作者 Haizheng DANG Dingli BAO +7 位作者 Zhiqian GAO Tao ZHANG Jun TAN Rui ZHA Jiaqi LI Ning LI Yongjiang ZHAO Bangjian ZHAO 《能源前沿:英文版》 CSCD 2019年第3期450-463,共14页
This paper establishes a theoretical model of the single-compressor-driven (SCD) three-stage Stirlingtype pulse tube cryocooler (SPTC) and conducts experimental verifications. The main differences between the SCD type... This paper establishes a theoretical model of the single-compressor-driven (SCD) three-stage Stirlingtype pulse tube cryocooler (SPTC) and conducts experimental verifications. The main differences between the SCD type and the multi-compressor-driven (MCD) crycooler are analyzed, such as the distribution of the input acoustic power in each stage and the optimization of the operating parameters, in which both advantages and difficulties of the former are stressed. The effects of the dynamic temperatures are considered to improve the accuracy of the simulation at very low temperatures, and a specific simulation example aiming at 10 K is given in which quantitative analyses are provided. A SCD threestage SPTC is developed based on the theoretical analyses and with a total input acoustic power of 371.58 W, which reaches a no-load temperature of 8.82 K and can simultaneously achieve the cooling capacities of 2.4 W at 70 K, 0.17 W at 25 K, and 0.05 W at 10 K. The performance of the SCD three-stage SPTC is slightly poorer than that of its MCD counterpart developed in the same laboratory, but the advantages of lightweight and compactness make the former more attractive to practical applications. 展开更多
关键词 single-compressor-driven three-stage Stirling-type PULSE tube CRYOCOOLER THEORETICAL modeling experimental verification
中国特色社会主义政治经济学的逻辑框架
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作者 陈昊 丁晓钦 《海派经济学》 2019年第2期1-13,共13页
中特政经的逻辑框架包括逻辑起点、理论逻辑、历史逻辑、实践逻辑和最终目标等基本组成部分。分别回答中特政经理论研究从何开始、源自什么、经历过什么、如何持续正确发展、最终又有什么终极目标的若干重要逻辑问题。另外,中特政经“... 中特政经的逻辑框架包括逻辑起点、理论逻辑、历史逻辑、实践逻辑和最终目标等基本组成部分。分别回答中特政经理论研究从何开始、源自什么、经历过什么、如何持续正确发展、最终又有什么终极目标的若干重要逻辑问题。另外,中特政经“以人民为中心”为逻辑起点,最后又回到“以人民为中心”的最终目标,将其逻辑框架构造成了一个不断螺旋上升的理论体系,为中特政经理论未来的研究和演进提供了逻辑借鉴。 展开更多
关键词 中特政经 逻辑框架 理论、历史逻辑和实践逻辑
Separation, Quantification and Structural Study of (+)-Catechin and (-)-Epicatechin by Ion Mobility Mass Spectrometry Combined with Theoretical Algorithms
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作者 Xinyu Bian Bing Zhao +4 位作者 Bo Pang Zhong Zheng Shu Liu Zhiqiang Liu Fengrui Song 《中国化学:英文版》 SCIE CAS CSCD 2019年第6期581-587,共7页
Two catechin epimers and their non-covalent complexes with γ-cyclodextrin were studied by using ion mobility coupled with mass spectrometry (IM-MS). Rapid separation of complexes was achieved with the peak-to-peak re... Two catechin epimers and their non-covalent complexes with γ-cyclodextrin were studied by using ion mobility coupled with mass spectrometry (IM-MS). Rapid separation of complexes was achieved with the peak-to-peak resolution reaching 0.86 after optimization of IM condition. Collision cross section (CCS) was measured to explore the structural difference of complexes. A gap of 11.75 A^2 between two complexes was found. Molecular modeling and theoretical CCS calculation were adopted to explain the measurement results. Two binding ways of both complexes were found and the calculated CCS corresponds accurately to the measured CCS. Quantification of catechins in mixtures was performed and the relative error was less than 15%, indicating the effectiveness of quantification by IM-MS. 展开更多
关键词 IM-MS CATECHIN cycodextrin THEORETICAL modeling COLLISION cross section chiral RESOLUTION
Health care in light of different theories of health--A proposed framework for integrating a social humanistic perspective into health care
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作者 Lena Gronblom Lundstrom Ulrika Aasa +1 位作者 Yan Zhang Tobias Sundberg 《结合医学学报:英文版》 CAS CSCD 2019年第5期321-327,共7页
The objective of this paper is to provide an overview of the biomedical,the biopsychosocial, and the social humanistic theories of health and to propose a framework for integrating the latter into health care. In summ... The objective of this paper is to provide an overview of the biomedical,the biopsychosocial, and the social humanistic theories of health and to propose a framework for integrating the latter into health care. In summary, the definitions of health, illness and disease are essential to the practice of health care and play fundamental roles in how patients’ experiences of being ill are valued and assessed within health care systems. Principally, the biomedical perspective proceeds from pathoanatomical deficiencies defining disease and malfunction;the addition of psychosocial components forms a biopsychosocial perspective.In addition, the social humanistic perspective extends from a person’s will, their ability to act, and the possibility to fulfill wanted actions. Thus, health care that does not address the social humanistic perspective may lack the power to describe how these entities are related to the patient on a personal level;thus,the will of the patient is not always fully addressed. Importantly, by targeting the will of the patient and the patient’s ability to act, the proposed framework of integrating a social humanistic perspective into health care may further emphasize and strengthen the interrelatedness of medical perspectives. A framework for integrating a social humanistic perspective into health care is proposed and its potential impact on health care is discussed. 展开更多
关键词 THEORETICAL MODELS BIOMEDICAL Biopsychosocial SOCIAL HUMANISTIC Review
苹果园科学施肥的理论与技术基础 预览
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作者 郑文婧 惠建斌 《山西果树》 2019年第6期36-38,共3页
阐述了土壤的四大功能及农业肥料的发展历史,为果农认识肥料及正确选择肥料普及了相关知识。对大量研究结果进行汇总,提供了各主产区红富士树叶中矿质元素含量“标准值范围”制订参考值及苹果树生理周期内水分,总养分、钾、磷、根部生... 阐述了土壤的四大功能及农业肥料的发展历史,为果农认识肥料及正确选择肥料普及了相关知识。对大量研究结果进行汇总,提供了各主产区红富士树叶中矿质元素含量“标准值范围”制订参考值及苹果树生理周期内水分,总养分、钾、磷、根部生长变化曲线图,为果农优化施肥提供了参考与依据。并提出在选、配肥时,要与当地测土技术相结合,配施营养全面、均衡的肥料。 展开更多
关键词 苹果 施肥 理论 技术
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中国特色新型城镇化理论内涵的认知与建构
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作者 陈明星 叶超 +2 位作者 陆大道 隋昱文 郭莎莎 《地理学报:英文版》 SCIE CSCD 2019年第10期1681-1698,共18页
Since the reform and opening up in China, rapid urbanization has boosted the development of economy and society, but it has also been confronted by tremendous challenges.Multidisciplinary research has focused on the i... Since the reform and opening up in China, rapid urbanization has boosted the development of economy and society, but it has also been confronted by tremendous challenges.Multidisciplinary research has focused on the issue of a national new type of urbanization planning, leading to a transformation of China’s urbanization strategy. Further research,however, is needed to explore the theoretical basis for this new approach to urbanization.This paper summarizes the process of development of urbanization in China and describes its specific characteristics, including peri-urbanization, special national conditions, complicated factors, and governance system. China’s urbanization makes a great contribution to urbanization on a world scale. Moreover, the literature on the subject demonstrates the significance of urbanization to the discipline of human and economic geography and the scientific connotations of new urbanization, which is people-oriented, harmonious, inclusive, and sustainable. Against a background of humanism, new urbanization represents a transformation from population urbanization to people-oriented urbanization. There are six crucial scientific issues involved: people-oriented urbanization and equalization of basic public services;urbanization with integrated and coordinated urban and rural development;urbanization in the context of resources and environmental carrying capacity and climate change;diverse regional modes;spatial effect and mechanism;and big data and technical innovation. The paper aims to illustrate the theoretical framework of China’s new urbanization, providing references for both theoretical research and policy formulation. 展开更多
关键词 new URBANIZATION Chinese CHARACTERISTICS THEORETICAL connotations PEOPLE-ORIENTED URBANIZATION SUSTAINABLE URBANIZATION
A New Manganese(Ⅱ) Coordination Compound Constructed by 1,10-Phenanthroline Derivative and Chlorine Anions: Synthesis, Crystal Structure and Theoretical Calculation 预览
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作者 王秀艳 高文昱 +3 位作者 周筱绗 刘东雪 胡波 孔治国 《结构化学》 SCIE CAS CSCD 2019年第5期819-824,671共7页
The new manganese(Ⅱ) coordination compound,[Mn(Cl)2(L)2](1, L = 11-fluorodipyrido[3,2-a:2?,3?-c]phenazine), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crysta... The new manganese(Ⅱ) coordination compound,[Mn(Cl)2(L)2](1, L = 11-fluorodipyrido[3,2-a:2?,3?-c]phenazine), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. 1 crystallizes in monoclinic system, space group C2/c with a = 8.419(2), b = 12.286(2), c = 28.451(6)A,β= 95.889(3)°, V =2927.5(10)A3, Z = 4, C36 H16 MnF2 Cl2 N8, Mr = 724.41, Dc = 1.644 g/cm3, F(000)= 1460,μ(Mo Ka)= 0.691 mm-1, R = 0.0445 and wR = 0.0982. Adjacent compounds are stacked by one type of π-πinteraction among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π-π interaction among L ligands to give a 2D supramolecular layer. Moreover, the C-F···π interactions between the carbon atom of the L ligand and the pyrazine ring of the adjacent L ligand further stabilize the supramolecular layer of 1. In addition, natural bond orbital(NBO) analysis has been calculated by the B3LYP/LANL2DZ method, which shows obvious covalent interaction between the coordinated atoms and Mn(Ⅱ) ion. 展开更多
关键词 crystal structure coordination compound 11-fluoro-dipyrido[3 2-a? 3?-c]phenazine manganese(Ⅱ) theoretical calculation
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Experimental Study of Churning Losses in Swash Plate Axial Piston Pump 预览
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作者 Chongbo Jing Junjie Zhou Jichen Zhou 《北京理工大学学报:英文版》 EI CAS 2019年第3期529-535,共7页
The problem of the churning loss in swash plate axial piston machines is investigated through experimental measurement and theoretical analysis. Several works surrounding churning loss in hydraulic components have bee... The problem of the churning loss in swash plate axial piston machines is investigated through experimental measurement and theoretical analysis. Several works surrounding churning loss in hydraulic components have been proposed in the past, but few have conducted experimental studies and accounted for both dry and wet housing conditions. In this study,a specialized experimental setup is established, which includes a transparent test pump diligently designed for performing various functions of tests. The test pump can work as a real pump without losing any actual features of pump operation. The torque loss in both the dry housing pump and wet housing pump is measured in terms of the shaft speed and its predictive model is also developed analytically. The comparisons between measured and calculated torque loss are presented, showing how speed influences torque loss in both conditions. The advantage/disadvantages of the two cases are summarized. The significance of the test setup is highlighted by verifying the proposed model, which can advance the understanding of energy losses of high speed pumps in future. 展开更多
关键词 AXIAL PISTON PUMP CHURNING LOSSES experimental analysis THEORETICAL model
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Temperature-dependent evolution of surface charge screening and polarization at ferroelectric surfaces
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作者 LongFei Wang Yi Luo +8 位作者 JieSu Wang XiuShi Huang ZhaoMeng Gao TieYing Yang XiaoLong Li Pei Li KuiJuan Jin WeiFeng Zhang HaiZhong Guo 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第8期117-120,共4页
The polarization and domain behavior on the surface of a ferroelectric material are significantly affected by the screening processes [1-12].Recently,there has been a notable increase in the theoretical calculations a... The polarization and domain behavior on the surface of a ferroelectric material are significantly affected by the screening processes [1-12].Recently,there has been a notable increase in the theoretical calculations and experiments investigating the dynamics of polarization and domain behaviors coexisting in phase transitions of ferroelectric materials. 展开更多
关键词 significantly AFFECTED SCREENING processes THEORETICAL calculations
The Belt and Road Initiative from Three Theoretical Perspectives 预览
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作者 Fu Mengzi 《现代国际关系:英文版》 2019年第2期1-33,共33页
Efforts have generally been made from policy considerations to interpret reasons for the proposition of the Belt and Road Initiative and its global layout.Though they are of some significance,such a grand initiative c... Efforts have generally been made from policy considerations to interpret reasons for the proposition of the Belt and Road Initiative and its global layout.Though they are of some significance,such a grand initiative certainly has its own internal theoretical basis.This paper is in the opinion that the spillover effect of oversized economy,the extension of the value chain and its climbing effect,as well as channel suitability and location orientation constitute the endogenous driving forces of the Belt and Road Initiative.Each of the three theoretical perspectives has its own internal realistic basis,all of which may offer some reference that is conducive to understanding the practice and future development of the Belt and Road Initiative. 展开更多
关键词 the BELT and ROAD INITIATIVE ENDOGENOUS driving force theoretical BASIS in terconnection and interworki ng
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A New Model of Ferroelectric Phase Transition with Neglectable Tunneling Effect
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作者 尹红梅 周恒为 黄以能 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第7期14-18,共5页
Due to the obvious deviations of the existing theoretical models from the experimental results of ferroelectric phase transition, a new model is proposed on the basis of the coupling between spontaneous polarization a... Due to the obvious deviations of the existing theoretical models from the experimental results of ferroelectric phase transition, a new model is proposed on the basis of the coupling between spontaneous polarization and spontaneous strain in ferroelectrics. The spontaneous polarization and specific heat of ferroelectric phase transition predicted by the model are in better agreement with the corresponding data of triglyceride sulfate, a typical ferroelectric.In addition, the model predicts a new type of ferroelectric in which a phase transition and a phase-like transition coexist. 展开更多
关键词 DUE to the obvious DEVIATIONS THEORETICAL MODELS TRANSITION coexist
Risk prediction models for lung cancer:Perspectives and dissemination 预览
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作者 Wei Tang Qin Peng +9 位作者 Yanzhang Lyu Xiaoshuang Feng Xin Li Luopei Wei Ni Li Hongda Chen Wanqing Chen Ning Wu Jiang Li Yao Huang 《中国癌症研究:英文版》 SCIE CAS CSCD 2019年第2期316-328,共13页
Objective: The objective was to systematically assess lung cancer risk prediction models by critical evaluation of methodology, transparency and validation in order to provide a direction for future model development.... Objective: The objective was to systematically assess lung cancer risk prediction models by critical evaluation of methodology, transparency and validation in order to provide a direction for future model development.Methods: Electronic searches(including PubMed, EMbase, the Cochrane Library, Web of Science, the China National Knowledge Infrastructure, Wanfang, the Chinese BioMedical Literature Database, and other official cancer websites) were completed with English and Chinese databases until April 30 th, 2018. Main reported sources were input data, assumptions and sensitivity analysis. Model validation was based on statements in the publications regarding internal validation, external validation and/or cross-validation.Results: Twenty-two studies(containing 11 multiple-use and 11 single-use models) were included. Original models were developed between 2003 and 2016. Most of these were from the United States. Multivariate logistic regression was widely used to identify a model. The minimum area under the curve for each model was 0.57 and the largest was 0.87. The smallest C statistic was 0.59 and the largest 0.85. Six studies were validated by external validation and three were cross-validated. In total, 2 models had a high risk of bias, 6 models reported the most used variables were age and smoking duration, and 5 models included family history of lung cancer.Conclusions: The prediction accuracy of the models was high overall, indicating that it is feasible to use models for high-risk population prediction. However, the process of model development and reporting is not optimal with a high risk of bias. This risk affects prediction accuracy, influencing the promotion and further development of the model. In view of this, model developers need to be more attentive to bias risk control and validity verification in the development of models. 展开更多
关键词 LUNG NEOPLASMS carcinoma bronchogenic risk assessment models THEORETICAL
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Micro Model of Carbon Fiber/Cyanate Ester Composites and Analysis of Machining Damage Mechanism
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作者 Haitao Liu Jie Lin +1 位作者 Yazhou Sun Jinyang Zhang 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期198-208,共11页
Machining damage occurs on the surface of carbon fiber reinforced polymer (CFRP) composites during processing. In the current simulation model of CFRP, the initial defects on the carbon fiber and the periodic random d... Machining damage occurs on the surface of carbon fiber reinforced polymer (CFRP) composites during processing. In the current simulation model of CFRP, the initial defects on the carbon fiber and the periodic random distribution of the reinforcement phase in the matrix are not considered in detail, which makes the characteristics of the cutting model significantly different from the actual processing conditions. In this paper, a novel three-phase model of carbon fiber/cyanate ester composites is proposed to simulate the machining damage of the composites. The periodic random distribution of the carbon fiber reinforced phase in the matrix was realized using a double perturbation algorithm. To achieve the stochastic distribution of the strength of a single carbon fiber, a novel method that combines the Weibull intensity distribution theory with the Monte Carlo method is presented. The mechanical properties of the cyanate matrix were characterized by fitting the stress-strain curves, and the cohesive zone model was employed to simulate the interface. Based on the model, the machining damage mechanism of the composites was revealed using finite element simulations and by conducting a theoretical analysis. Furthermore, the milling surfaces of the composites were observed using a scanning electron microscope, to verify the accuracy of the simulation results. In this study, the simulations and theoretical analysis of the carbon fiber/cyanate ester composite processing were carried out based on a novel three-phase model, which revealed the material failure and machining damage mechanism more accurately. 展开更多
关键词 Carbon fiber reinforced polymer COMPOSITES MICRO simulation model MACHINING damage mechanism MILLING and observation experiment Theoretical ANALYSIS
A Theoretical Study on Transitional Shear Flow Behavior of the Compressible and Isothermal Thermoplastic Polymer
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作者 Dong-Lei Liu Feng Zhou Kun Fang 《高分子科学:英文版》 SCIE CAS CSCD 2019年第5期518-526,共9页
By extending the virtual conformational element of the polymer chain, a dynamic end-to-end(ETE) vector was presented to describe the chain’s instantaneous morphology based on the spring-bead theory. A feasible viscoe... By extending the virtual conformational element of the polymer chain, a dynamic end-to-end(ETE) vector was presented to describe the chain’s instantaneous morphology based on the spring-bead theory. A feasible viscoelastic model was proposed to describe the rheological behavior of the isothermal thermoplastic polymer materials, based on the molecular kinetics, thermodynamics, and continuum mechanics method. The model is simplified as the generalized Newton’s law. Its integral formula with similar form to the KBKZ model was also derived. Rheological experiments were carried out with the isotactic polypropylene material. The experimental results reveal that the viscoelastic model exhibits a three-stage rheological characteristic. There is a distinct high-elastic rheological region in the middle stage, reflecting the pseudoplastic fluids properties. Compared with the Ostwald-de Waele power law model, the viscoelastic model shows a better agreement with the rheological practices. 展开更多
关键词 Shear flow THEORETICAL model THERMOPLASTIC polymer RHEOLOGICAL experiments
Analysis of the mass of behind-armor debris generated by RHA subjected to normal penetration of variable cross-section EFP 预览
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作者 Boyang Xing Dongjiang Zhang +7 位作者 Zhenyan Guo Yunhui Hou Rui Guo Rongzhong Liu Liang Chen Hao Zhou Yongliang Yang Jianhua Luo 《Defence Technology(防务技术)》 CAS CSCD 2019年第3期390-397,共8页
Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively Formed Projectile (EFP) is the purpose of this paper. S... Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively Formed Projectile (EFP) is the purpose of this paper. So theoretical analysis, numerical simulation and experimental data are combined to analyze the influence of variable cross-section characteristic on the time history of crater radius. Moreover the relationships between time history of crater radius (as well as mass of BAD) and the thickness of RHA (from 30mm to 70 mm) and the impact velocity of EFP (1650 m/s to 1860 m/s) are also investigated. The results indicate that: 1) being compared to the variable cross-section characteristic is ignored, the theoretical time history of crater radius is in better agreement with the simulation results when the variable cross-section characteristic is considered;2) being compared to the other three conditions of plug, the theoretical mass of BAD is in the best agreement with the simulation results when the shape of plug is frustum of a cone and the angle between generatrix and bottom is 45- and the axial length of mushroom is considered. 展开更多
关键词 Explosively formed projectile Behind-armor DEBRIS Variable CROSS-SECTION characteristic Shape of plug AXIAL length of MUSHROOM Theoretical model
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Analytical modeling for rapid design of bistable buckled beams 预览
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作者 Wenzhong Yan Yunchen Yu Ankur Mehta 《力学快报:英文版》 CAS CSCD 2019年第4期264-272,I0003共10页
Double-clamped bistable buckled beams demonstrate great versatility in various fields such as robotics,energy harvesting,and microelectromechanical system(MEMS).However,their design often requires time-consuming and e... Double-clamped bistable buckled beams demonstrate great versatility in various fields such as robotics,energy harvesting,and microelectromechanical system(MEMS).However,their design often requires time-consuming and expensive computations.In this work,we present a method to easily and rapidly design bistable buckled beams subjected to a transverse point force.Based on the Euler–Bernoulli beam theory,we establish a theoretical model of bistable buckled beams to characterize their snapthrough properties.This model is verified against the results from a finite element analysis(FEA)model,with maximum discrepancy less than 7%.By analyzing and simplifying our theoretical model,we derive explicit analytical expressions for critical behavioral values on the force-displacement curve of the beam.These behavioral values include critical force,critical displacement,and travel,which are generally sufficient for characterizing the snapthrough properties of a bistable buckled beam.Based on these analytical formulas,we investigate the influence of a bistable buckled beam's key design parameters,including its actuation position and precompression,on its critical behavioral values,with our results validated by FEA simulations.Our analytical method enables fast and computationally inexpensive design of bistable buckled beams and can guide the design of complicated systems that incorporate bistable mechanisms. 展开更多
关键词 BISTABLE buckled beam THEORETICAL model SNAP-THROUGH characteristics Off-center ACTUATION Analytical expression Rapid design
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Theoretical models and experimental determination methods for equations of state of silicate melts: A review
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作者 Juntao HOU Qiong LIU 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第5期751-770,共20页
Silicate melts are very active in the interior of the Earth and other terrestrial planets, and are important carriers for the transport of material and energy. The determination of the equation of state(EOS) for silic... Silicate melts are very active in the interior of the Earth and other terrestrial planets, and are important carriers for the transport of material and energy. The determination of the equation of state(EOS) for silicate melts and the acquisition of a precise quantitative relationship between molar volume(or density) and temperature, pressure, and composition is essential for simulating the generation, migration, and eruption processes of magmas and the evolution of the magma ocean stage during the early formation of the Earth and other terrestrial planets, for calculating and modeling the phase equilibria involving silicate melts, and for revealing the variation of the microstructure of silicate melts with pressure. However, it is experimentally challenging to determine the volumetric properties of silicate melts and the accumulated density data at high pressure are still very limited due to a series of problems such as: the high liquidus temperature of silicate rocks;proneness for silicate melts to react with sample capsules to change the melt composition;and proneness for melts to flow and leak during the high pressure and high temperature experiments. In recent years, there is rapid progress in the high pressure and high temperature experimental techniques, in terms of not only the extension of temperature and pressure ranges but also the improvement on the accuracy of measurements, and the emergence of new methods for in-situ measurements. Here, we review the widely-used theoretical models of ambient-pressure and high-pressure EOS for silicate melts, and illustrate some problems that need to be solved urgently:(1) the room pressure EOS for iron-and titanium-bearing silicate melts needs to be improved;(2) the partial molar properties of the H2 O and CO2 components in silicate melts containing volatile components may vary markedly with the melt composition, which need to be addressed in high-pressure EOS;(3) how the formulation and applicable range of EOS correspond to changes in melt structure and compression 展开更多
关键词 SILICATE MELTS EQUATIONS of state THEORETICAL models Determination METHODS MELT structure Compression mechanisms
The Application of Theoretical Models in the Studies of Physical Activity Behaviors of the Elderly in China 预览
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作者 Yuquan Chen Yuqi Wang +2 位作者 Fanxuan Meng Zifei Du Qun Zuo 《医学科学进展杂志(英文)》 2019年第2期29-33,共5页
By using the method of literature review, this paper introduces the popular theoretical models which have shown to better explain physical activity behaviors at a certain degree, summarizes the dominating theoretical ... By using the method of literature review, this paper introduces the popular theoretical models which have shown to better explain physical activity behaviors at a certain degree, summarizes the dominating theoretical models in the studies of physical activity behaviors of the elderly in China. In addition, shortcomings and future prospects are pointed out at the end. 展开更多
关键词 The application of THEORETICAL MODELS The ELDERLY PHYSICAL activity BEHAVIORS China
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Experimental,Numerical and Simplified Theoretical Model Study for Internal Solitary Wave Load on FPSO with Emphasis on Scale Effect 预览
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作者 ZHANG Rui-rui CHEN Ke YOU Yun-xiang 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第1期26-33,共8页
Scale effect of ISWs loads on Floating Production Storage and Offloading(FPSO)is studied in this paper.The application conditions of KdV,eKdV and MCC ISWs theories are used in the numerical method.The depthaveraged ve... Scale effect of ISWs loads on Floating Production Storage and Offloading(FPSO)is studied in this paper.The application conditions of KdV,eKdV and MCC ISWs theories are used in the numerical method.The depthaveraged velocities induced by ISWs are used for the velocity-inlet boundary.Three scale ratio numerical models λ=1,20 and 300 were selected,which the scale ratio is the size ratio of numerical models to the experimental model.The comparisons between the numerical and former experimental results are performed to verify the feasibility of numerical method.The comparisons between the numerical and simplified theoretical results are performed to discuss the applicability of the simplified theoretical model summarized from the load experiments.Firstly,the numerical results of λ=1 numerical model showed a good agreement with former experimental and simplified theoretical results.It is feasible to simulate the ISWs loads on FPSO by the numerical method.Secondly,the comparisons between the results of three scale ratio numerical models and experimental results indicated that the scale ratios have more significant influence on the experimental horizontal forces than the vertical forces.The scale effect of horizontal forces mainly results from the different viscosity effects associated with the model’s dimension.Finally,through the comparisons between the numerical and simplified theoretical results for three scale ratio models,the simplified theoretical model of the pressure difference and friction forces exerted by ISWs on FPSO is applied for large-scale or full-scale FPSO. 展开更多
关键词 scale effect FPSO INTERNAL SOLITARY wave NUMERICAL simulation simplified THEORETICAL model
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