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ICC跨文化交际能力教学模式下军事英语教学策略探究
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作者 李驰 崇斯伟 《中国科技经济新闻数据库 教育》 2024年第4期0127-0130,共4页
全球化背景下,世界各国国防力量已聚焦国际舞台。各国军事行动和军事合作交流日益频繁,这对军事人员的外语能力提出了更高的要求。因此,跨文化能力已成为衡量国际化环境下新型军事人才综合素质的重要尺度。作为开展军事英语教学的院校,... 全球化背景下,世界各国国防力量已聚焦国际舞台。各国军事行动和军事合作交流日益频繁,这对军事人员的外语能力提出了更高的要求。因此,跨文化能力已成为衡量国际化环境下新型军事人才综合素质的重要尺度。作为开展军事英语教学的院校,培养和提高学员的跨文化能力成为亟待探究的重要课题。本研究基于英国语言学家Byram提出的ICC (Intercultural Communicative Competence) 文化教学模式,从军事英语跨文化教学出发,探索培养和提高学员的跨文化交际能力的相关策略,充分发挥军事英语在对外交往中的桥梁纽带作用,为培养军事国际化人才提供有效借鉴。 展开更多
关键词 跨文化交际能力 icc模式 军事英语
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Molecular Dynamics, Diffusion Coefficients and Activation Energy of the Electrolyte (Anode) in Lithium (Li and Li+), Sodium (Na and Na+) and Potassium (K and K+)
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作者 Alain Second Dzabana Honguelet Timothée Nsongo +1 位作者 Bitho Rodongo Earvin Loumbandzila 《Modeling and Numerical Simulation of Material Science》 2024年第1期39-57,共19页
This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studi... This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studied;with and without gap. In this work, we present the structural, physical and chemical properties of the lithium, sodium and potassium electrodes. For the structural properties, the cohesive energy and the mesh parameters were calculated, revealing that, whatever the chemical element selected, the compact hexagonal hcp structure is the most stable, followed by the face-centred cubic CFC structure, and finally the BCC structure. The most stable structure is lithium, with a cohesion energy of -6570 eV, and the lowest bcc-hcp transition energy of -0.553 eV/atom, followed by sodium. For physical properties, kinetic and potential energies were calculated for each of the sectioned chemical elements, with lithium achieving the highest value. Finally, for the chemical properties, we studied the diffusion coefficient and the activation energy. Only potassium followed an opposite order to the other two, with the quantities with lacunae being greater than those without lacunae, whatever the multiplicity. The order of magnitude of the diffusion coefficients is given by the relationship D<sub>Li</sub> > D<sub>Na</sub> > D<sub>k</sub> for the multiplicity 6*6*6, while for the activation energy the order is reversed. 展开更多
关键词 Molecular Dynamics Diffusion coefficients Activation Energy LITHIUM Alkali Metals MEAM Potential
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Adaptive Random Effects/Coefficients Modeling
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作者 George J. Knafl 《Open Journal of Statistics》 2024年第2期179-206,共28页
Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using general... Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time. 展开更多
关键词 Adaptive Regression Correlated Outcomes Extended Linear Mixed Modeling Fractional Polynomials Likelihood Cross-Validation Random Effects/coefficients
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Evaluation of the coefficient of lateral stress at rest of granular materials under repetitive loading conditions
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作者 Heerym Han Hyunwook Choo Junghee Park 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1709-1721,共13页
Although the internal stress state of soils can be affected by repetitive loading,there are few studies evaluating the lateral stress(or K_(0))of soils under repetitive loading.This study investigates the changes in K... Although the internal stress state of soils can be affected by repetitive loading,there are few studies evaluating the lateral stress(or K_(0))of soils under repetitive loading.This study investigates the changes in K_(0) and directional shear wave velocity(V_(s))in samples of two granular materials with different particle shapes during repetitive loading.A modified oedometer cell equipped with bender elements and a diaphragm transducer was developed to measure the variations in the lateral stress and the shear wave velocity,under repetitive loading on the loading and unloading paths.The study produced the following results:(1)Repetitive loading on the loading path resulted in an increase in the K_(0) of test samples as a function of cyclic loading number(i),and(2)Repetitive loading on the unloading path resulted in a decrease in K_(0) according to i.The shear wave velocity ratio(i.e.V_(s)(HH)/V_(s)(VH),where the first and second letters in parentheses corresponds to the directions of wave propagation and particle motion,respectively,and V and H corresponds to the vertical and horizontal directions,respectively)according to i supports the experimental observations of this study.However,when the tested material was in lightly over-consolidated state,there was an increase in K_(0) during repetitive loading,indicating that it was the initial K_(0),rather than the loading path,which is responsible for the change in K_(0).The power model can capture the variation in the K_(0) of samples according to i.Notably,the K_(0)=1 line acts as the boundary between the increase and decrease in K_(0) under repetitive loading. 展开更多
关键词 coefficient of lateral stress at rest Repetitive loading Granular materials Shear wave velocity Stiffness anisotropy
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Determination of Natural Logarithm of Diffusion Coefficient and Activation Energy of Thin Layer Drying Process of Ginger Rhizome Slices
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作者 Austin Ikechukwu Gbasouzor Sam Nna Omenyi +1 位作者 Sabuj Mallik Jude E. Njoku 《World Journal of Engineering and Technology》 2024年第1期213-228,共16页
This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhiz... This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhizome. Drying of ginger was modeled, and then the effective diffusion coefficient and activation energy were determined. For this purpose, the experiments were done at six levels of varied temperatures: 10°C, 20°C, 30°C, 40°C, 50°C and 60°C. The values of effective diffusion coefficients obtained in this work for the variously treated ginger rhizomes closely agreed with the average effective diffusion coefficients of other notable authors who determined the drying kinetics and convective heat transfer coefficients of ginger slices. 展开更多
关键词 Activation Energy Diffusion coefficients Ginger Rhizomes Drying Model Drying Time Moisture Ratio Thin Layer
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Thermomechanical Dynamics (TMD) and Bifurcation-Integration Solutions in Nonlinear Differential Equations with Time-Dependent Coefficients
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第5期1733-1743,共11页
The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple ba... The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple back-and-forth motion develops into water drinking motion. The solution to a drinking bird equation of motion manifests itself the transition from thermodynamic equilibrium to nonequilibrium irreversible states. The independent solution signifying a nonequilibrium thermal state seems to be constructed as if two independent bifurcation solutions are synthesized, and so, the solution is tentatively termed as the bifurcation-integration solution. The bifurcation-integration solution expresses the transition from mechanical and thermodynamic equilibrium to a nonequilibrium irreversible state, which is explicitly shown by the nonlinear differential equation with time-dependent coefficients (NDE-TC). The analysis established a new theoretical approach to nonequilibrium irreversible states, thermomechanical dynamics (TMD). The TMD method enables one to obtain thermodynamically consistent and time-dependent progresses of thermodynamic quantities, by employing the bifurcation-integration solutions of NDE-TC. We hope that the basic properties of bifurcation-integration solutions will be studied and investigated further in mathematics, physics, chemistry and nonlinear sciences in general. 展开更多
关键词 The Nonlinear Differential Equation with Time-Dependent coefficients The Bifurcation-Integration Solution Nonequilibrium Irreversible States Thermomechanical Dynamics (TMD)
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解读《幸福终点站》中维克多·纳沃斯基的跨文化能力——基于拜拉姆ICC模型
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作者 梁静儿 《今古文创》 2024年第16期95-97,共3页
外语能力不等同跨文化能力,在通过英语电影学习语言的同时必须要有跨文化的意识。电影《幸福终点站》讲述了东欧人纳沃斯基在肯尼迪机场的跨文化适应,他凭借积极的心态和出色的动手能力赢得了他人的尊重和爱戴。纳沃斯基在机场的经历是... 外语能力不等同跨文化能力,在通过英语电影学习语言的同时必须要有跨文化的意识。电影《幸福终点站》讲述了东欧人纳沃斯基在肯尼迪机场的跨文化适应,他凭借积极的心态和出色的动手能力赢得了他人的尊重和爱戴。纳沃斯基在机场的经历是一例精彩的跨文化互动,本文基于拜拉姆的ICC理论模型对他的跨文化能力进行解读,以期为英语学习者培养跨文化能力提供参考。 展开更多
关键词 《幸福终点站》 跨文化适应 拜拉姆icc模型 跨文化能力
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基于印刷机ICC色彩管理的再现意图分析
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作者 江新忠 张玉娜 刘少恒 《广东印刷》 2023年第5期24-26,共3页
在ICC色彩管理体系中,设备的颜色特性和介质、观察、测量颜色的条件等信息都保存在特性文件中,供色彩转换模块调用,以便实现不同设备间的颜色转换。因此ICC特性文件在色彩管理中起着重要作用。但是因为特性文件是一个电子文件,即使建立... 在ICC色彩管理体系中,设备的颜色特性和介质、观察、测量颜色的条件等信息都保存在特性文件中,供色彩转换模块调用,以便实现不同设备间的颜色转换。因此ICC特性文件在色彩管理中起着重要作用。但是因为特性文件是一个电子文件,即使建立了特性文件,也不知道其中包含的数据是什么,或者这些数据代表的颜色特性是什么,很难对其进行检验。1993年,由国际色彩联盟ICC提出了用于色彩管理的ICC标准,此标准中定义了视觉、饱和度、相对色度、绝对色度4种基本的再现意图。 展开更多
关键词 icc特性文件 电子文件 颜色特性 再现意图 icc标准 色彩转换 颜色转换 印刷机
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基于喷墨打印机ICC色彩管理的再现意图分析
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作者 江新忠 杨荣辉 梁征 《广东印刷》 2023年第1期17-19,共3页
国际色彩联盟ICC提出了用于色彩管理的ICC标准,此标准中定义了视觉、饱和度、相对色度、绝对色度4种基本的再现意图。ICC色彩管理中颜色转换的再现意图,也被称之为转换目的或再现目的或渲染方法,它是颜色在进行色貌变换和色域映射时的... 国际色彩联盟ICC提出了用于色彩管理的ICC标准,此标准中定义了视觉、饱和度、相对色度、绝对色度4种基本的再现意图。ICC色彩管理中颜色转换的再现意图,也被称之为转换目的或再现目的或渲染方法,它是颜色在进行色貌变换和色域映射时的选择依据,选择不同的再现意图,所得到的特性连接色空间值(PCS)不同,最后得到的颜色复制效果也是不同的。因此,再现意图在色彩管理中是一个非常关键的概念,选择合适的再现意图才能得到用户所希望的颜色复制效果。 展开更多
关键词 喷墨打印机 色域映射 再现意图 颜色复制 icc标准 颜色转换 渲染方法 选择依据
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基于最大信息系数的关联性特征选择算法:MICCFS
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作者 罗幼喜 谢昆明 +1 位作者 胡超竹 李翰芳 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第6期777-785,共9页
针对基于关联性特征选择算法(CFS)对于回归任务只能识别变量线性关系和分类任务使用对称不确定性度量的不足,提出一种基于最大信息系数(MIC)的CFS特征选择算法:MICCFS.将回归任务中衡量变量间的线性相关系数和分类任务中的对称不确定性... 针对基于关联性特征选择算法(CFS)对于回归任务只能识别变量线性关系和分类任务使用对称不确定性度量的不足,提出一种基于最大信息系数(MIC)的CFS特征选择算法:MICCFS.将回归任务中衡量变量间的线性相关系数和分类任务中的对称不确定性度量改进为MIC度量方式.运用最佳优先搜索算法搜索特征子集,以UCI机器学习数据库中11个回归数据集和10个分类数据集为实验对象,采用支持向量机、k近邻算法、朴素贝叶斯模型、决策树四种分类器,比较了MICCFS和CFS以及常用特征选择方法SVMRFE、Lasso、MIM、Relief F、Chi-Square的效果,结果表明MICCFS具有一定优势. 展开更多
关键词 关联性特征选择 最大信息系数 特征选择 分类 降维
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基于“以枢调枢”与ICC线粒体自噬相关性探讨芪石升降归元饮治疗GERD的理论基础
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作者 罗贞艺 张羽 +5 位作者 蒙华莹 张云燕 黎丽群 刘礼剑 谭金晶 谢胜 《世界科学技术-中医药现代化》 CSCD 北大核心 2023年第9期2989-2995,共7页
脏腑经络枢机失衡所致的消化道动力障碍与胃食管反流病(Gastroesophageal reflux disease,GERD)发病相关,脾胃为气机之枢纽,可以运化水谷精微转化为能量,而任督统诸身之阴阳,构成人体最大的脏腑经络交感循环系统,故任督二气之交感平衡... 脏腑经络枢机失衡所致的消化道动力障碍与胃食管反流病(Gastroesophageal reflux disease,GERD)发病相关,脾胃为气机之枢纽,可以运化水谷精微转化为能量,而任督统诸身之阴阳,构成人体最大的脏腑经络交感循环系统,故任督二气之交感平衡是脾胃枢机条衡的原动力;Cajal间质细胞(Interstitial cells of Cajal,ICC)是消化道动力之枢纽,可以通过线粒体自噬途径维持线粒体能量代谢功能,改善消化道动力。故本文以脏腑经络枢机之枢转驱动ICC线粒体能量平衡的“以枢调枢”理论为切入点,探讨了GERD“任督二脉枢机失衡-脾胃运化功能失调”以及“ICC线粒体自噬障碍-ICC起搏与传导功能失常-消化道动力障碍”的分子生物学理论基础,并阐释基于“以枢调枢”创立的中药复方芪石升降归元饮治疗GERD的可行性,有助于实现“以枢调枢”理论的微观化、具体化及实现中医药理论的现代化,并为GERD的诊疗提供理论依据。 展开更多
关键词 胃食管反流病 以枢调枢 icc 线粒体自噬 芪石升降归元饮
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《英语国家社会与文化入门》课程教学中跨文化交际能力培养探析--基于Byram的ICC理论模型 被引量:1
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作者 刘淑珍 居永梅 《邢台职业技术学院学报》 2023年第1期11-13,84,共4页
Byram(1997)提出的ICC理论模型是西方跨文化交际理论研究领域内最有影响的模型之一。文章根据Byram(1997)的ICC理论模型,从态度、知识、技能和批判性文化意识四个维度,详细论述了《英语国家社会与文化入门》课程教学中如何设计课堂活动... Byram(1997)提出的ICC理论模型是西方跨文化交际理论研究领域内最有影响的模型之一。文章根据Byram(1997)的ICC理论模型,从态度、知识、技能和批判性文化意识四个维度,详细论述了《英语国家社会与文化入门》课程教学中如何设计课堂活动,提升英语专业学生跨文化交际能力。 展开更多
关键词 icc理论模型 跨文化交际能力 商务英语专业
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Advances in joint roughness coefficient (JRC) and its engineering applications 被引量:2
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作者 Nick Barton Changshuo Wang Rui Yong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3352-3379,共28页
The joint roughness coefficient (JRC), introduced in Barton (1973) represented a new method in rock mechanics and rock engineering to deal with problems related to joint roughness and shear strength estimation. It has... The joint roughness coefficient (JRC), introduced in Barton (1973) represented a new method in rock mechanics and rock engineering to deal with problems related to joint roughness and shear strength estimation. It has the advantages of its simple form, easy estimation, and explicit consideration of scale effects, which make it the most widely accepted parameter for roughness quantification since it was proposed. As a result, JRC has attracted the attention of many scholars who have developed JRC-related methods in many areas, such as geological engineering, multidisciplinary geosciences, mining mineral processing, civil engineering, environmental engineering, and water resources. Because of such a developing trend, an overview of JRC is presented here to provide a clear perspective on the concepts, methods, applications, and trends related to its extensions. This review mainly introduces the origin and connotation of JRC, JRC-related roughness measurement, JRC estimation methods, JRC-based roughness characteristics investigation, JRC-based rock joint property description, JRC's influence on rock mass properties, and JRC-based rock engineering applications. Moreover, the representativeness of the joint samples and the determination of the sampling interval for rock joint roughness measurements are discussed. In the future, the existing JRC-related methods will likely be further improved and extended in rock engineering. 展开更多
关键词 Joint roughness coefficient(JRC) Rock joints ROUGHNESS Shear strength Scale effect
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Analysis of burnup performance and temperature coefficient for a small modular molten‑salt reactor started with plutonium 被引量:1
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作者 Xue‑Chao Zhao Yang Zou +1 位作者 Rui Yan Xiang‑Zhou Cai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第1期178-189,共12页
In a thorium-based molten salt reactor(TMSR),it is difficult to achieve the pure 232Th–^(233)U fuel cycle without sufficient^(233)U fuel supply.Therefore,the original molten salt reactor was designed to use enriched ... In a thorium-based molten salt reactor(TMSR),it is difficult to achieve the pure 232Th–^(233)U fuel cycle without sufficient^(233)U fuel supply.Therefore,the original molten salt reactor was designed to use enriched uranium or plutonium as the starting fuel.By exploiting plutonium as the starting fuel and thorium as the fertile fuel,the high-purity^(233)U produced can be separated from the spent fuel by fluorination volatilization.Therefore,the molten salt reactor started with plutonium can be designed as a^(233)U breeder with the burning plutonium extracted from a pressurized water reactor(PWR).Combining these advantages,the study of the physical properties of plutonium-activated salt reactors is attractive.This study mainly focused on the burnup performance and temperature reactivity coefficient of a small modular molten-salt reactor started with plutonium(SM-MSR-Pu).The neutron spectra,^(233)U production,plutonium incineration,minor actinide(MA)residues,and temperature reactivity coefficients for different fuel salt volume fractions(VF)and hexagon pitch(P)sizes were calculated to analyze the burnup behavior in the SM-SMR-Pu.Based on the comparative analysis results of the burn-up calculation,a lower VF and larger P size are more beneficial for improving the burnup performance.However,from a passive safety perspective,a higher fuel volume fraction and smaller hexagon pitch size are necessary to achieve a deep negative feedback coefficient.Therefore,an excellent burnup performance and a deep negative temperature feedback coefficient are incompatible,and the optimal design range is relatively narrow in the optimized design of an SM-MSR-Pu.In a comprehensive consideration,P=20 cm and VF=20%are considered to be relatively balanced design parameters.Based on the fuel off-line batching scheme,a 250 MWth SM-MSR-Pu can produce approximately 29.83 kg of ^(233)U,incinerate 98.29 kg of plutonium,and accumulate 14.70 kg of MAs per year,and the temperature reactivity coefficient can always be lower than−4.0pcm/K. 展开更多
关键词 Molten salt fuel Incinerate plutonium 233U production Temperature reactivity coefficient
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Prediction models of the ionization coefficient and ionization cross-section based on multi-layer molecular parameters 被引量:1
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作者 邱睿 周文俊 +2 位作者 郑宇 侯华 王宝山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第5期93-103,共11页
Prediction models were proposed to estimate the reduced Townsend ionization coefficient and ionization cross-section.A shape function of the reduced Townsend ionization coefficient curves was derived from the ionizati... Prediction models were proposed to estimate the reduced Townsend ionization coefficient and ionization cross-section.A shape function of the reduced Townsend ionization coefficient curves was derived from the ionization collision probability model.The function had three parameters:the first ionization potential energy,A_(α),and B_(α).A_(α)and B_(α)were related to the molecule symmetry and size.The polarization of molecules could characterize the molecule symmetry.The multi-layer molecular cross-section(MMCS)was proposed to describe the contributions of electrons and molecule radius on different molecule surfaces to collisions.A prediction model of the ionization cross-section was also proposed based on Aα.The molecule parameters were calculated by the Becke3–Lee–Yang–Parr(B3LYP)method and the 6–311G**basis set.We used available data of 30 and 23 gases,respectively,to build the prediction models of reduced Townsend ionization coefficients and ionization cross-sections.The relationships between the molecular parameters Aαand Bαand the ionization cross-section were built up via nonlinear fittings.The determination coefficients R^(2)of Aα,Bα,and the ionization cross-section were 0.877,0.887,and 0.838,respectively.The results showed that the accuracy of models was positively correlated with the molecule symmetry and reduced electric field.This was mainly related to the accuracy of the MMCS model in predicting Aα.The MMCS model needed to be improved to describe the collision direction selectivity caused by the molecule asymmetry.Under a high reduced electric field,that error of Aαhad less influence on the prediction results.However,the prediction results for single atoms with high symmetry were poor.This may be due to the absolute error of the model close to single atoms’reduced Townsend ionization coefficients.The models could provide the basis for gas insulation prediction and discharge calculations,especially for symmetric molecules under a high electric field. 展开更多
关键词 Townsend ionization coefficient ionization cross-section gas discharge eco-friendly insulation gases
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Determination of rock mass integrity coefficient using a non-invasive geophysical approach 被引量:1
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作者 Muhammad Hasan Yanjun Shang +2 位作者 Xuetao Yi Peng Shao Meng He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1426-1440,共15页
Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the ... Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the most efficient parameters,which is conventionally determined from boreholes.Such approaches,however,are time-consuming and expensive,offer low data coverage of point measurements,require heavy equipment,and are hardly conducted in steep topographic sites.Hence,borehole approaches cannot assess the subsurface thoroughly for rock mass quality evaluation.Alternatively,use of geophysical methods is non-invasive,rapid and economical.The proposed geophysical approach makes useful empirical correlation between geophysical and geotechnical parameters.We evaluated the rock mass quality via integration between KV measured from the limited boreholes and inverted resistivity obtained from electrical resistivity tomography(ERT).The borehole-ERT correlation provided KV along various geophysical profiles for more detailed 2D/3D(two-/three-dimensional)mapping of rock mass quality.The subsurface was thoroughly evaluated for rock masses with different engineering qualities,including highly weathered rock,semi-weathered rock,and fresh rock.Furthermore,ERT was integrated with induced polarization(IP)to resolve the uncertainty caused by water/clay content.Our results show that the proposed method,compared with the conventional approaches,can reduce the ambiguities caused by inadequate data,and give more accurate insights into the subsurface for rock mass quality evaluation. 展开更多
关键词 Geotechnical engineering Rock mass integrity coefficient Rock mechanical parameters Geophysical parameters Electrical resistivity tomography(ERT) Induced polarization(IP)
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Remaining useful life prediction based on nonlinear random coefficient regression model with fusing failure time data 被引量:1
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作者 WANG Fengfei TANG Shengjin +3 位作者 SUN Xiaoyan LI Liang YU Chuanqiang SI Xiaosheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期247-258,共12页
Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a n... Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a nonlinear random coefficient regression(RCR) model with fusing failure time data.Firstly, some interesting natures of parameters estimation based on the nonlinear RCR model are given. Based on these natures,the failure time data can be fused as the prior information reasonably. Specifically, the fixed parameters are calculated by the field degradation data of the evaluated equipment and the prior information of random coefficient is estimated with fusing the failure time data of congeneric equipment. Then, the prior information of the random coefficient is updated online under the Bayesian framework, the probability density function(PDF) of the RUL with considering the limitation of the failure threshold is performed. Finally, two case studies are used for experimental verification. Compared with the traditional Bayesian method, the proposed method can effectively reduce the influence of imperfect prior information and improve the accuracy of RUL prediction. 展开更多
关键词 remaining useful life(RUL)prediction imperfect prior information failure time data NONLINEAR random coefficient regression(RCR)model
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Impacts of Surface Exchange Coefficients on Simulations of Super Typhoon Megi(2010)Using a Coupled Ocean-Atmosphere-Wave Model
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作者 ZHANG Wenqing ZHANG Jialin +1 位作者 GUAN Changlong SUN Jian 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期587-600,共14页
In this study,the effects of surface exchange coefficients on simulations of Super Typhoon Megi(2010)are investigated using a fully coupled ocean-atmosphere-wave model.Several experiments are conducted using different... In this study,the effects of surface exchange coefficients on simulations of Super Typhoon Megi(2010)are investigated using a fully coupled ocean-atmosphere-wave model.Several experiments are conducted using different parameterization schemes for the drag(C_(D))and enthalpy exchange(C_(K))coefficients.For the selected case,considering only the leveling-off of C_(D)at high wind speeds does not effectively improve the simulated typhoon track,intensity,or size.We found that increasing C_(K)monotonically with wind speed(Komori et al.,2018)yields stronger winds and deeper pressures by enhancing latent and sensible heat fluxes,but typhoon intensity remains underestimated.We propose a new higher C_(K)than that from Komori et al.(2018)based on the theory of Emanuel(1995).This approach produces a greater modeled typhoon intensity that is in good agreement with the best track data and effectively improves the track error for the simulation.Improved accuracy for modeled typhoon intensity is achieved with the new coefficient because C_(K)/C_(D)reaches the threshold of about 0.75 predicted by Emanuel(1995).The new proposed C_(K)also results in a reasonably accurate modeled sea surface temperature.However,typhoon size and surface wave height are overestimated.This finding implies that more numerical tests for tropical cyclones of different nature(such as strong,weak,dissipating,rapidly intensifying,or weakening tropical cyclones)should be studied,and more physical processes should be explored in future coupled models. 展开更多
关键词 TYPHOON drag coefficient enthalpy exchange coefficient coupled ocean-atmosphere-wave model
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覆土浅埋滴灌玉米分阶段亏水条件下AquaCrop与Dual Crop Coefficient模型精度对比研究 被引量:1
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作者 戚迎龙 赵举 +3 位作者 宁小莉 李彬 李敏 史海滨 《东北农业大学学报》 CAS CSCD 北大核心 2023年第6期64-77,共14页
近年来,西辽河流域地下水超采问题日益突出,改进灌溉技术降低农业用水可有效解决这一问题,但该技术缺乏科学的水分管理方法及适宜的理论模型。基于单阶段及多阶段亏水情形试验,对比同类农田水分模型精度,优选阶段性亏水管理辅助模型。... 近年来,西辽河流域地下水超采问题日益突出,改进灌溉技术降低农业用水可有效解决这一问题,但该技术缺乏科学的水分管理方法及适宜的理论模型。基于单阶段及多阶段亏水情形试验,对比同类农田水分模型精度,优选阶段性亏水管理辅助模型。研究设置7个玉米分阶段亏水调控处理,于2018、2019年进行田间小区试验,取得2个同类模型的本地化参数并比较其模拟精度。结果表明,AquaCrop和双作物系数模型可相近表达玉米冠层发育到最大而未开始衰减期间土壤水分的消耗过程,而对快速生长期与后期1m土层贮水量的模拟差异大。AquaCrop模型在土壤贮水量偏低时高估其实测值,其他情形正负偏差分布相对均匀,双作物系数模型多数情形低估其实测值。AquaCrop模型描述玉米各阶段蒸散量因亏水情形而变化能力优于双作物系数模型。AquaCrop模型和双作物系数模型的标准均方根误差平均值在模拟1 m土层贮水量时分别为4.494%~8.443%、6.017%~8.626%,在模拟蒸散量时分别为8.158%~9.510%、5.980%~15.022%。综合来看,AquaCrop模型表现更好,推荐作为适宜西辽河流域覆土浅埋滴灌玉米水分管理模型。研究可为该区域覆土浅埋滴灌种植玉米选出适宜的水分管理模型,理解新技术条件下玉米分阶段亏水调控机制及田间灌溉管理优化提供参考。 展开更多
关键词 模型精度 AquaCrop模型 双作物系数模型 覆土浅埋滴灌 玉米分阶段亏水
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Vertical Diffusion Coefficient with Stratification Effect for Silty Sediment Suspension Under Waves
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作者 YANG Guang-yao ZHANG Qing-he 《China Ocean Engineering》 SCIE EI CSCD 2023年第2期323-332,共10页
To analyze previous experimental data of suspended sediment concentration for silty sediment with different sediment particle sizes due to waves, a new stratification correction coefficient is presented. The suspended... To analyze previous experimental data of suspended sediment concentration for silty sediment with different sediment particle sizes due to waves, a new stratification correction coefficient is presented. The suspended sediment concentration gradient and sediment particle diameter are selected as parameters. Furthermore, a diffusion coefficient model with a stratification effect over the whole water depth for silty sediment suspension under waves is developed. The comparison between the suspended sediment concentration calculated by the presented model and several groups of experimental data shows that the model can reasonably reflect the vertical distribution of silty sediment suspension.The stratification effect calculated by the present model decreases with an increase in the sediment particle diameter,which indicates that the model can be extended to describe the suspended sediment concentration of fine to medium sand when the near-bottom sediment concentration is not very high. Although the original model needs to be iteratively solved, the approximate method without iteration is recommended for applications when the near bottom sediment concentration is between 10 and 20 kg/m~3 due to the small difference between the non-iterative and iterative solution for near bed layer suspended sediment concentration, which plays a major role in sediment transport. 展开更多
关键词 STRATIFICATION silty sediment suspension diffusion coefficient WAVE
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