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Exploration of Curriculum Ideology and Politics Integrating Medical Humanities Cultivation Model to Enhance Medical Core Values
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作者 Wenjuan Ni Ranhao Li +1 位作者 Yaqing Guo Wei Wang 《Journal of Contemporary Educational Research》 2024年第5期1-7,共7页
Purpose:To explore the application effect of the cultivation mode of Curriculum Ideology and Political Integration of Medical Humanities to enhance the core values of medicine in the clinical internship stage of medic... Purpose:To explore the application effect of the cultivation mode of Curriculum Ideology and Political Integration of Medical Humanities to enhance the core values of medicine in the clinical internship stage of medical students.Methods:Students in the clinical internship stage of the First Affiliated Hospital of Baotou Medical College were selected,and a total of 156 students in one random class in each grade were taken as the observation group and received the integration cultivation mode;148 students were taken as the control group and employed the traditional mode.The teaching effect of interns in the two groups was analyzed.Results:The teaching performance of students in both groups after clinical internship teaching was improved compared with that before admission;the teaching performance,teaching effect,teaching evaluation,and teaching satisfaction of the observation group were higher than that of the control group.Conclusion:The integration of the medical humanities training model with curriculum ideology and politics in the clinical internship of medical students is conducive to the improvement of teaching performance,teaching evaluation,teaching satisfaction of teachers and students,and the development and improvement of core values of medical students,which is of good value for teaching application. 展开更多
关键词 curriculum ideology and politics Medical humanities Medical students core values Clinical internship
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Displacement Field Variable Modeling Method for Heterogeneous Materials in Wind Power Blade Core Plates
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作者 Ying He Yongshuang Wen +3 位作者 Xuemei Huang Leian Zhang Rujun Song Chang Li 《Energy Engineering》 EI 2023年第2期445-459,共15页
In order to study the mechanical properties of the heterogeneous core plate of the wind turbine blade,a modeling method of the core plate based on displacement field variables is proposed.Firstly,the wind turbine blad... In order to study the mechanical properties of the heterogeneous core plate of the wind turbine blade,a modeling method of the core plate based on displacement field variables is proposed.Firstly,the wind turbine blade core plate was modeled according to the theory of modeling heterogeneous material characteristics.Secondly,the three-point bending finite element model of the wind turbine blade core plate was solved by the display dynamic equation to obtain the deformation pattern and force-deformation relationship of the core plate.Finally,the three-point bending static test was conducted to compare with the finite element analysis.The test results show that:the damage form of the wind turbine blade core plate includes elasticity,yield,and failure stages.The main failure modes are plastic deformation,core material collapse,and panel-core delamination.The failure load measured by the test is 1.59 kN,which is basically consistent with the load-displacement result obtained by the simulation,with a difference of only 1.9%,which verifies the validity and reliability of the model.It provides data references for wind turbine blade structure design. 展开更多
关键词 Blade core plate heterogeneous material modeling method finite element analysis PVC material
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A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
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作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
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Estimation of free core nutation parameters and availability of computing options
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作者 Weiwei Yang Xiaoming Cui +2 位作者 Jianqiao Xu Qingchao Liu Ming Qin 《Geodesy and Geodynamics》 EI CSCD 2024年第1期61-74,共14页
The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interfe... The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interferometry(VLBI) provide good observation techniques for detecting the FCN parameters.However,some choices in data processing and solution procedures increase the uncertainty of the FCN parameters.In this study,we analyzed the differences and the effectiveness of weight function and ocean tide corrections in the FCN parameter detection using synthetic data,SG data from thirty-one stations,and the 10 celestial pole offset(CPO) series.The results show that significant discrepancies are caused by different computing options for a single SG station.The stacking method,which results in a variation of0.24-5 sidereal days(SDs) in the FCN period(T) and 10^(3)-10^(4) in the quality factor(Q) due to the selection of the weighting function and the ocean tide model(OTM),can effectively suppress this influence.The statistical analysis results of synthetic data shows that although different weight choices,while adjusting the proportion of diurnal tidal waves involved,do not significantly improve the accuracy of fitted FCN parameters from gravity observations.The study evaluated a series of OTMs using the loading correction efficiency.The fitting of FCN parameters can be improved by selecting the mean of appropriate OTMs based on the evaluation results.Through the estimation of the FCN parameters based on the forced nutation,it was found that the weight function P_(1) is more suitable than others,and different CPO series(after 2009) resulted in a difference of 0.4 SDs in the T and of 103 in the Q.We estimated the FCN parameters for SG(T=430.4±1.5 SDs and Q=1.52×10^(4)±2.5×10^(3)) and for VLBI(T=429.8±0.7 SDs,Q=1.88×10^(4)±2.1×10^(3)). 展开更多
关键词 Free core nutation Superconducting gravimeter Very long baseline interferometry Weight function Ocean tide model
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Changes in filtration and capacitance properties of highly porous reservoir in underground gas storage:CT-based and geomechanical modeling
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作者 Valerii Khimulia Vladimir Karev +1 位作者 Yury Kovalenko Svyatoslav Barkov 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2982-2995,共14页
The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage facility.The geomechanical part of the res... The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage facility.The geomechanical part of the research included studying the dependence of rock permeability on the stress-strain state in the vicinity of the wells,and physical modeling of the implementation of the method of increasing the permeability of the wellbore zone-the method of directional unloading of the reservoir.The digital part of the research included computed tomography(CT)-based computer analysis of the internal structure,pore space characteristics,and filtration properties before and after the tests.According to the results of physical modeling of deformation and filtration processes,it is found that the permeability of rocks before fracture depends on the stress-strain state insignificantly,and this influence is reversible.However,when downhole pressure reaches 7-8 MPa,macrocracks in the rock begin to grow,accompanied by irreversible permeability increase.Porosity,geodesic tortuosity and permeability values were obtained based on digital studies and numerical modeling.A weak degree of transversal anisotropy of the filtration properties of rocks was detected.Based on the analysis of pore size distribution,pressure field and flow velocities,high homogeneity and connectivity of the rock pore space is shown.The absence of pronounced changes in pore space characteristics and pore permeability after non-uniform triaxial loading rocks was shown.On the basis of geometrical analysis of pore space,the reasons for weak permeability anisotropy were identified.The filtration-capacitance properties obtained from the digital analysis showed very good agreement with the results of field and laboratory measurements.The physical modeling has confirmed the efficiency of application of the directional unloading method for the reservoir under study.The necessary parameters of its application were calculated:bottomhole geometry,stage of operation,stresses and pressure drawdown value. 展开更多
关键词 Permeability anisotropy Reservoir porosity Rocks computed tomography(CT) Digital core analysis Filtration flow numerical modeling
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Dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact
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作者 N.SHAHVEISI S.FELI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期155-178,共24页
The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are investigate... The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are investigated.The current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial velocity.For the layer analysis,the high-order shear deformation theory(HSDT)and Frostig's second model for the displacement fields of the core layer are used.The classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of time.In order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the LVI.Finite element(FE)simulations are conducted by means of the ABAQUS software.The effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed. 展开更多
关键词 analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory
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基于CORE模型的古街文旅体验产品设计 被引量:1
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作者 徐建 《包装工程》 CAS 北大核心 2023年第24期483-491,共9页
目的 古街需要形成浓郁的人文氛围和商业环境,通过开发具有优良体验感的文旅产品,为现有文旅产品增加更多互动体验的环节。这不仅可以让游客充分感受古街的地域特色,增强出行动机,也可以使游客有节奏地体验到古街文旅产品中传达的信息,... 目的 古街需要形成浓郁的人文氛围和商业环境,通过开发具有优良体验感的文旅产品,为现有文旅产品增加更多互动体验的环节。这不仅可以让游客充分感受古街的地域特色,增强出行动机,也可以使游客有节奏地体验到古街文旅产品中传达的信息,从而对产品体验形成获得感、满足感、认同感等感受,以促进古街文旅产业发展。方法 基于CORE模型,采用观察法、文献研究法、探索性研究法收集当下古街文旅产品体验的趣味点,结合头脑思维风暴,借鉴游戏、玩具、劳动实践中体验感好的部分,组织设计行动及体验活动,重视产品体验心理过程的反馈。结果 设计创新性体验产品及体验流程,通过李克特量表及Kano模型对产品方案进行评估。结论 在设计新产品时,重点展现文旅产品的趣味体验,对在售产品提供体验活动思路及行动方案,从而提升游客对地域特色文化的感受力。 展开更多
关键词 文旅产品 体验 core模型 古街
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APPLICATION OF THE SHRINKING CORE MODEL TO THE KINETICS OF ZINC OXIDE DESULFURIZATION 被引量:3
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作者 李彦旭 张栓兵 +1 位作者 郭汉贤 钟炳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第4期14-21,共8页
The kinetics of H<sub>2</sub>S removal by zinc oxide desulfurizer was studied through thermogravimetricanalysis.The experimental results show that desulfurization rate was controlled,at high temperatureand... The kinetics of H<sub>2</sub>S removal by zinc oxide desulfurizer was studied through thermogravimetricanalysis.The experimental results show that desulfurization rate was controlled,at high temperatureand low conversion,by the chemical reaction rate,and at low temperature and high conversion by thegrain diffusion rate.The reaction is first order with respect to H<sub>2</sub>S concentration in the differentcontrolled stages.The kinetic behavior can be modeled through the employment of the shrinking coremodel.The values of the model parameters were determined.The variation tendencies with temperatureand concentration of H<sub>2</sub>S at the controlled stages were discussed. 展开更多
关键词 hydrogen SULFIDE DESULFURIZATION KINETICS SHRINKING core model
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The Selection and Breeding of a Novel Microorganism Strain I and Investigation of Core Model Experiment for MEOR 被引量:4
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作者 ZhangZhongzhi WeiXiaofang LuoYijing LiQingzhong LeiGuanglun 《Petroleum Science》 SCIE CAS CSCD 2005年第2期95-102,共8页
This paper introduces the results of selecting and breeding a micro-organism, Strain I, and its core model experiment investigation for microbial enhanced oil recovery (MEOR). Strain I was separated from the formation... This paper introduces the results of selecting and breeding a micro-organism, Strain I, and its core model experiment investigation for microbial enhanced oil recovery (MEOR). Strain I was separated from the formation water of the Dagang oil field, with analytical results showing that Strain I is a gram-positive bacillus. A further study revealed that this strain has an excellent tolerance of environmental stresses: It can survive in conditions of 70℃, 30 wt% salinity and pH3.5-9.4. Strain I can metabolize biosurfactants that could increase the oil recovery ratio, use crude oil as the single carbon source, and decompose long-chain paraffin with a large molecular weight into short-chain paraffin with a small molecular weight. The core model experiment shows that Strain I enhances oil recovery well. Using 2 vol% of the fermentation solution of Strain I to displace the crude oil in the synthetic plastic bonding core could increase the recovery ratio by 21.6%. 展开更多
关键词 BIOSURFACTANT THERMOTOLERANCE salinity tolerance core model flooding experiment microbial enhanced oil recovery.
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Numerical modeling of metamorphic core complex formation:Implications for the destruction of the North China Craton 被引量:6
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作者 ZiQi Ma Gang Lu +1 位作者 JianFeng Yang Liang Zhao 《Earth and Planetary Physics》 EI CSCD 2022年第2期191-203,共13页
Widespread magmatism, metamorphic core complexes(MCCs), and significant lithospheric thinning occurred during the Mesozoic in the North China Craton(NCC). It has been suggested that the coeval exhumation of MCCs with ... Widespread magmatism, metamorphic core complexes(MCCs), and significant lithospheric thinning occurred during the Mesozoic in the North China Craton(NCC). It has been suggested that the coeval exhumation of MCCs with uniform northwest-southeast shear senses and magmatism probably resulted from a decratonization event during the retreat of the paleo-Pacific Plate. Here we used two-dimensional finite element thermomechanical numerical models to investigate critical parameters controlling the formation of MCCs under far-field extensional stress. We observed three end-member deformation modes: the MCC mode, the symmetric-dome mode, and the pure-shear mode. The MCC mode requires a Moho temperature of ≥700 ℃ and an extensional strain rate of ≥5 × 10^(-16)s^(-1), implying that the lithosphere had already thinned when the MCC was formed in the Mesozoic. Considering that the widespread MCCs have the same northwest-southeast extension direction in the NCC, we suggest that the MCCs are surface expressions of both large-scale extension and craton destruction and that rollback of the paleo-Pacific slab might be the common driving force. 展开更多
关键词 metamorphic core complex North China Craton numerical modeling EXTENSION
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Mathematical modeling for dynamic stability of sandwich beam with variable mechanical properties of core 被引量:3
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作者 M.GRYGOROWICZ E.MAGNUCKA-BLANDZI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第10期1361-1374,共14页
The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The ... The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The field of displacements is for- mulated using the classical broken line hypothesis and the proposed nonlinear hypothesis that generalizes the classical one. Using both hypotheses, the strains are determined as well as the stresses of each layer. The kinetic energy, the elastic strain energy, and the work of load are also determined. The system of equations of motion is derived using Hamilton's principle. Finally, the system of three equations is reduced to one equation of motion, in particular, the Mathieu equation. The Bubnov-Galerkin method is used to solve the system of equations of motion, and the Runge-Kutta method is used to solve the second-order differential equation. Numerical calculations are done for the chosen family of beams. The critical loads, unstable regions, angular frequencies of the beam, and the static and dynamic equilibrium paths are calculated analytically and verified numerically. The results of this study are presented in the forms of figures and tables. 展开更多
关键词 mathematical modelling dynamic stability metal foam core with variable mechanical property static and dynamic equilibrium path angular frequency
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Developing a curriculum model of English teaching for master's degree nursing education in a Chinese medicine university 被引量:2
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作者 Heng Zhang Sheng-Ji Jin Shi-Zheng Du 《International Journal of Nursing Sciences》 CSCD 2020年第1期99-104,共6页
Objective:English for Specific Purpose(ESP)is the essence for developing scientific research capacity,which is a core component for postgraduate education.The objective of this article is to develop a curriculum model... Objective:English for Specific Purpose(ESP)is the essence for developing scientific research capacity,which is a core component for postgraduate education.The objective of this article is to develop a curriculum model for ESP of Master's level nursing education in a Chinese medicine university.Method:A three-year action research approach with continuous reflection and modification was used to develop an ESP curriculum based on the RICH model.A total of 78 students of Master's Science in Nursing enrolled in 2016-2018 and three course teachers in Nanjing University of Chinese Medicine participated in the study.The ESP curriculum based on the RICH model involved research-based learning topics(R),integrated curriculum(Ⅰ),cooperative learning methods(C),and humanistic outcome(H).Results:The passing rate of the students was 100%,the excellent rate was 79.5%,with an average score of 83.16±3.43.All students were satisfied with the ESP course design and acknowledged the process of"growing up under the pressure".Four students have published five articles in the journals included by Science Citation Index(SCI).Conclusions:The study exerted a positive effect on the ESP teaching and learning and provided new ideas for the ESP curriculum integration of Master's Science in Nursing in China. 展开更多
关键词 English for specific purpose curriculum model POSTGRADUATE NURSING education
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Mathematical simulation of hot metal desulfurization during KR process coupled with an unreacted core model 被引量:3
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作者 Yanyu Zhao Wei Chen +1 位作者 Shusen Cheng Lifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期758-766,共9页
A three-dimensional mathematical model was established to predict the multiphase flow,motion and dispersion of desulfurizer particles,and desulfurization of hot metal during the Kanbara reactor(KR)process.The turbulen... A three-dimensional mathematical model was established to predict the multiphase flow,motion and dispersion of desulfurizer particles,and desulfurization of hot metal during the Kanbara reactor(KR)process.The turbulent kinetic energy-turbulent dissipation rate(k-ε)turbulence model,volume-of-fluid multiphase model,discrete-phase model,and unreacted core model for the reaction between the hot metal and particles were coupled.The measured sulfur content of the hot metal with time during the actual KR process was employed to validate the current mathematical model.The distance from the lowest point of the liquid level to the bottom of the ladle decreased from 3170 to2191 mm when the rotation speed increased from 30 to 110 r/min,which had a great effect on the dispersion of desulfurizer particles.The critical rotation speed for the vortex to reach the upper edge of the stirring impeller was 70 r/min when the immersion depth was 1500 mm.The desulfurization rate increased with the increase in the impeller rotation speed,whereas the influence of the immersion depth was relatively small.Formulas for different rotation parameters on the desulfurization rate constant and turbulent energy dissipation rate were proposed to evaluate the variation in sulfur content over time. 展开更多
关键词 DESULFURIZATION unreacted core model desulfurizer dispersion KR process fluid flow
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Geostatistics Studies and Geochemical Modeling Based on Core Data,Sheytoor Iron Deposit,Iran 被引量:6
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作者 Aref Shirazi Adel Shirazy +1 位作者 Shahab Saki Ardeshir Hezarkhani 《Journal of Geological Resource and Engineering》 2018年第3期124-133,共10页
In general,the purpose of the mineralization modeling is the advancement of a mineral exploration project and ultimately,the extractive design of a deposit,which is one of the most important stages in mining engineeri... In general,the purpose of the mineralization modeling is the advancement of a mineral exploration project and ultimately,the extractive design of a deposit,which is one of the most important stages in mining engineering.Mineralization modeling is divided into two general categories,superficial and deep modeling.In surface modeling,the aim is finding abnormal locations in terms of mineralization at the study area,which is commonly used in the early stages of exploration as one of the means for locating exploratory boreholes.After drilling in the study area with the aim of identifying mineralization and reserve estimation it is necessary to obtain deep mineralization position and its geometric features,using statistical and modeling methods.Using mathematical,statistical and modeling methods,we can predict the position of iron mineralization in places where drilling is not done and eventually reach a three-dimensional model of the mineral materials underground.As a case study,the deep information about the boreholes of the sheytoor mining area in Yazd province of Iran was investigated.Iron mineralization was modeled as 2D cumulative model and 3D block model,and the results were presented.Finally the geochemical threshold and the anomalous limit of iron element are calculated by concentration-volume(C-V)fractal method in this deposit.Geochemical threshold and the anomalous limit for Fe in this deposit are 24.7%and 34.3%respectively. 展开更多
关键词 ORE modeling C-V FRACTAL method IRON DEPOSIT core data sheytoor
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Poroelastic finite-difference modeling for ultrasonic waves in digital porous cores 被引量:1
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作者 Li-Yun Fu Yan Zhang +2 位作者 Zhenglin Pei Wei Wei Luxin Zhang 《Earthquake Science》 2014年第3期285-299,共15页
Scattering attenuation in short wavelengths has long been interesting to geophysicists. Ultrasonic coda waves, observed as the tail portion of ultrasonic wavetrains in laboratory ultrasonic measurements, are important... Scattering attenuation in short wavelengths has long been interesting to geophysicists. Ultrasonic coda waves, observed as the tail portion of ultrasonic wavetrains in laboratory ultrasonic measurements, are important for such studies where ultrasonic waves interact with smallscale random heterogeneities on a scale of micrometers, but often ignored as noises because of the contamination of boundary reflections from the side ends of a sample core. Numerical simulations with accurate absorbing boundary can provide insight into the effect of boundary reflections on coda waves in laboratory experiments. The simulation of wave propagation in digital and heterogeneous porous cores really challenges numerical techniques by digital image of poroelastic properties, numerical dispersion at high frequency and strong heterogeneity, and accurate absorbing boundary schemes at grazing incidence. To overcome these difficulties, we present a staggered-grid high-order finite-difference (FD) method of Biot's poroelastic equations, with an arbitrary even-order (2L) accuracy to simulate ultrasonic wave propagation in digital porous cores with strong heterogeneity. An unsplit convolutional perfectly matched layer (CPML) absorbing boundary, which improves conventional PML methods at grazing incidence with less memory and better computational efficiency, is employed in the simulation to investigate the influence of boundary reflections on ultra- sonic coda waves. Numerical experiments with saturated poroelastic media demonstrate that the 2L FD scheme with the CPML for ultrasonic wave propagation significantly improves stability conditions at strong heterogeneity and absorbing performance at grazing incidence. The boundary reflections from the artificial boundary surrounding the digital core decay fast with the increase of CPML thick- nesses, almost disappearing at the CPML thickness of 15 grids. Comparisons of the resulting ultrasonic coda Qsc values between the numerical and experimental ultrasonic S waveforms for a cylindrical rock sample demonstrate that the boundary reflection may contribute around one-third of the ultrasonic coda attenuation observed in laboratory experiments. 展开更多
关键词 Digital porous cores Ultrasonic coda Poroelastic finite-difference modeling Unsplitconvolutional PML absorbing boundary
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Simulation of double cold cores of the 35°N section in the YellowSea with a wave-tide-circulation coupled model 被引量:7
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作者 夏长水 乔方利 +2 位作者 张勐宁 杨永增 袁业立 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第3期292-298,共7页
Based on the MASNUM wave-tide-circulation coupled numerical model, the temperature structure along 35°N in the Yellow Sea was simulated and compared with the observations. One of the notable features of the tempe... Based on the MASNUM wave-tide-circulation coupled numerical model, the temperature structure along 35°N in the Yellow Sea was simulated and compared with the observations. One of the notable features of the temperature structure along 35°N section is the double cold cores phenomena during spring and summer. The double cold cores refer to the two cold water centers located near 122°E and 125°E from the depth of 30m to bottom. The formation, maintenance and disappearance of the double cold cores are discussed. At least two reasons make the temperature in the center (near 123°E) of the section higher than that near the west and east shores in winter. One reason is that the water there is deeper than the west and east sides so its heat content is higher. The other is invasion of the warm water brought by the Yellow Sea Warm Current (YSWC) during winter.This temperature pattern of the lower layer (from 30m to bottom) is maintained through spring and summer when the upper layer (0 to 30m) is heated and strong thermocline is formed. Large zonal span of the 35°N section (about 600 km) makes the cold cores have more opportunity to survive. The double cold cores phenomena disappears in early autumn when the west cold core vanishes first with the dropping of the thermocline position. 展开更多
关键词 数字模型 波浪 潮汐 环流 黄海
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Reversed-phase fused-core HPLC modeling of peptides 被引量:3
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作者 Matthias D'Hondt Bert Gevaert +5 位作者 Sofie Stalmans Sylvia Van Dorpe Evelien Wynendaele Kathelijne Peremans Christian Burvenich Bart De Spiegeleer 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第2期93-101,共9页
Different fused-core stationary phase chemistries(C18,Amide,Phenyl-hexyl and Peptide ES-C18) were used for the analysis of 21 structurally representative model peptides.In addition,the effects of the mobile phase co... Different fused-core stationary phase chemistries(C18,Amide,Phenyl-hexyl and Peptide ES-C18) were used for the analysis of 21 structurally representative model peptides.In addition,the effects of the mobile phase composition(ACN or MeOH as organic modifier;formic acid or acetic acid,as acidifying component) on the column selectivity,peak shape and overall chromatographic performance were evaluated.The RP-amide column,combined with a formic acid-acetonitrile based gradient system,performed as best.A peptide reversed-phase retention model is proposed,consisting of 5 variables:log SumAA,log Sv,clog P,log nHDon and log nHAcc.Quantitative structure-retention relationship(QSRR) models were constructed for 16 different chromatographic systems.The accuracy of this peptide retention model was demonstrated by the comparison between predicted and experimentally obtained retention times,explaining on average 86% of the variability.Moreover,using an external set of 5 validation peptides,the predictive power of the model was also demonstrated.This peptide retention model includes the novel in-silico calculated amino acid descriptor,AA,which was calculated from log P,3D-MoRSE,RDF and WHIM descriptors. 展开更多
关键词 Peptides Fused-corecore-shell core-enhanced poro-shell HALO s) stationary phases RP-HPLC peptide retention model In-silico amino acid descriptor
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Shell and shrinking core kinetics model of Mg-based hydrogen storage alloys
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作者 于振兴 王尔德 +3 位作者 张文丛 房文斌 孙宏飞 梁吉 《中国有色金属学会会刊:英文版》 CSCD 2005年第S2期178-182,共5页
The kinetics equation of the Mg-based hydrogen storage alloys (Mg-Ni-MO) was established by the shell and shrinking core model. The total coefficients of the kinetics equation of the hydrogen absorption and desorption... The kinetics equation of the Mg-based hydrogen storage alloys (Mg-Ni-MO) was established by the shell and shrinking core model. The total coefficients of the kinetics equation of the hydrogen absorption and desorption process with shell diffusion as the controlling step were determined by semi-empirical and semi-theoretical methods, and the apparent activation energy of the hydrogen absorption process was obtained. The calculation results can well accord with the experimental data, and can well forecast the hydrogen storage capacity and absorption rate at different times. By using the kinetics equation, the effects of temperature and pressure on the hydrogen storage process can also be well understood. The kinetics equation is helpful for the design of the hydrogen storage container. 展开更多
关键词 Mg-based ALLOYS hydrogen storage SHELL and core SHRINKING model KINETICS EQUATION
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Overall Features of EAST Operation Space by Using Simple Core-SOL-Divertor Model 被引量:1
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作者 R.HIWATARI A.HATAYAMA +2 位作者 朱思铮 T.TAKIZUKA Y.TOMITA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第1期114-117,共4页
A simple Core-SOL-Divertor (C-S-D) model has been developed to investigate qualitatively the overall features of the operational space for the integrated core and edge plasma. To construct the simple C-S-D model, a ... A simple Core-SOL-Divertor (C-S-D) model has been developed to investigate qualitatively the overall features of the operational space for the integrated core and edge plasma. To construct the simple C-S-D model, a simple core plasma model of ITER physics guidelines and a two-point SOL-divertor model are used. The simple C-S-D model is applied to the study of the EAST operational space with lower hybrid current drive experiments under various kinds of trade-off for the basic plasma parameters. Effective methods for extending the operational space are also presented, From this study for the EAST operational space, it is evident that the C-S-D model is a useful tool for understanding qualitatively the overall features of the plasma operational space. 展开更多
关键词 divertor modeling particle balance core-edge interface EAST
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The keele curriculum model: A contemporary framework for designing an inter-professional technology enhanced nursing curriculum
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作者 Melanie Humphreys Ian Wood +4 位作者 Carol D. Johnson Pauline N. Walsh Nicola Witton Julie Green Sarah Corkhill 《Open Journal of Nursing》 2013年第4期358-362,共5页
This paper outlines a curriculum model for contemporary programme design for the purpose of embedding educational innovation and technology within an inter-professional nursing curriculum. It has been developed from w... This paper outlines a curriculum model for contemporary programme design for the purpose of embedding educational innovation and technology within an inter-professional nursing curriculum. It has been developed from work within the School of Nursing and Midwifery at Keele University during the re-write of both the nursing and midwifery curriculum. The Nursing and Midwifery Council (NMC) require approval of all recordable programmes every five years and as such the school took this review as an opportunity to explore the curriculum model currently in use and develop an approach that would facilitate the professional requirements of the programme alongside the embedding of innovative learning and teaching methodologies. The model springs from extensive application of contemporary pedagogy underpinning adult learning, and forces consideration of cognitive alignment within a multi-modal delivery framework [1]. The model builds upon the early work of Fowler and Mayes [2] and later work of Bird [3] who explored the antecedents and underpinning theory for success within online learning experiences. This model has greater reach;having strategic fit for acontemporary “technology enhanced learning” application within further and higher education [4], whilst ensuring the achievement of given professional standards [5]. 展开更多
关键词 NURSING curriculum INTER-PROFESSIONAL Technology-Enhanced model Keele
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