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Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles 被引量:2
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作者 Wei Wang Yuchen Wang +2 位作者 Shiwei Chen Yongcang Guo Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期282-294,共13页
This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glideguided projectile(SGGP),addressing model uncertainties and external disturbances.Based on fixed-time stable theor... This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glideguided projectile(SGGP),addressing model uncertainties and external disturbances.Based on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial conditions.By introducing an error integral signal,the dynamics of the SGGP are transformed into two separate second-order fully actuated systems.Subsequently,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a constant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired eigenstructure.Under the proposed composite control framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov method.Validation of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations. 展开更多
关键词 Spinning glide-guided projectile Attitude control Sliding mode disturbance observer Fixed-time stable theory high-order fully actuated approach
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Basic Terms in Shiology-Revealing the Connotation and Extension of the Core Concept of Shiance Cognition
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作者 Liu Guangwei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第4期86-96,共11页
Shiology,abbreviated from the study of shiance,stands as a"disciplinary category"level knowledge system.Within the Chinese educational system's subject catalog,it is an extension of agricultural science(... Shiology,abbreviated from the study of shiance,stands as a"disciplinary category"level knowledge system.Within the Chinese educational system's subject catalog,it is an extension of agricultural science(09),and it is a knowledge system that integrates the eater needs,food acquisition and shiance order.Cognition of previously unrecognized objects requires new concepts,and the construction of a new knowledge system cannot be separated from the support of new concepts.Shiance knowledge system is a huge collection of shiance concepts,and this research limits its discussion to the connotations and extensions of four core groups of concepts:shiance,food,eaters,and eating.These core concepts of shiance knowledge also serve as the foundational terms for constructing the shiology framework.Establishing the foundational terms and definitions of shiology is a fundamental research endeavor.If one were to liken the shiology framework to a building,then its foundational terms are akin to the"bricks";defining these terms is comparable to setting standards for these"bricks",facilitating the construction of a more robust structure.The basic words discussed in this research include 34 in the category of"shiance",31 in the category of"food",seven in the category of"eaters"and 16 in the category of"eating".These basic words play a fundamental and leading role in the process of constructing the system of shiology system,and they are used in the names of 40 subjects in the 53 basic shiology systems.The absence and narrowing of cognitive concepts are at the root of the lack of systematic governance of human shiance issues. 展开更多
关键词 term shiology shiology term shiance FOOD eater eatin
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Tunable spectral continuous shift of high-order harmonic generation in atoms by a plasmon-assisted shaping pulse
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作者 王源 李玉龙 +7 位作者 乔月 高娜 郭福明 陈洲 赫兰海 杨玉军 赵曦 王俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期433-440,共8页
We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position... We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position in the harmonic emission by adjusting the absolute phase parameter within the frequency domain of the shaping pulse.This phenomenon holds potential significance for experimental setups necessitating precisely tuned single harmonics.Notably,we observe a modulated shift in the created harmonic photon energy,spanning an impressive range of 1.2 eV.This frequency peak shift is rooted in the asymmetry exhibited by the rising and falling edges of the laser pulse,directly influencing the position of the peak frequency emission.Our study quantifies the dependence of this tuning range and the asymmetry of the laser pulse,offering valuable insights into the underlying mechanisms driving this phenomenon.Furthermore,our investigation uncovers the emergence of semi-integer order harmonics as the phase parameter is altered.We attribute this discovery to the intricate interference between harmonics generated by the primary and secondary return cores.This observation introduces an innovative approach for generating semi-integer order harmonics,thus expanding our understanding of high-order harmonic generation.Ultimately,our work contributes to the broader comprehension of complex phenomena in laser-matter interactions and provides a foundation for harnessing these effects in various applications,particularly those involving precise spectral control and the generation of unique harmonic patterns. 展开更多
关键词 high-order harmonic semi-integer-order spectra shift inhomogeneous field
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Elliptically polarized high-order harmonic generation of Ar atom in an intense laser field
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作者 胡杰 王一琛 +6 位作者 景秋霜 姜威 王革文 赵逸文 肖礴 梁红静 马日 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期453-457,共5页
High-order harmonic generation(HHG) of Ar atom in an elliptically polarized intense laser field is experimentally investigated in this work.Interestingly,the anomalous ellipticity dependence on the laser ellipticity(... High-order harmonic generation(HHG) of Ar atom in an elliptically polarized intense laser field is experimentally investigated in this work.Interestingly,the anomalous ellipticity dependence on the laser ellipticity(ε) in the lower-order harmonics is observed,specifically in the 13rd-order,which displays a maximal harmonic intensity at ε ≈ 0.1,rather than at ε = 0 as expected.This contradicts the general trend of harmonic yield,which typically decreases with the increase of laser ellipticity.In this study,we attribute this phenomenon to the disruption of the symmetry of the wave function by the Coulomb effect,leading to the generation of a harmonic with high ellipticity.This finding provides valuable insights into the behavior of elliptically polarized harmonics and opens up a potential way for exploring new applications in ultrafast spectroscopy and light–matter interactions. 展开更多
关键词 high-order harmonic generation Coulomb effect elliptically polarized intense laser field
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High-order Bragg forward scattering and frequency shift of low-frequency underwater acoustic field by moving rough sea surface
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作者 莫亚枭 张朝金 +2 位作者 鹿力成 孙启航 马力 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期459-470,共12页
Acoustic scattering modulation caused by an undulating sea surface on the space-time dimension seriously affects underwater detection and target recognition.Herein,underwater acoustic scattering modulation from a movi... Acoustic scattering modulation caused by an undulating sea surface on the space-time dimension seriously affects underwater detection and target recognition.Herein,underwater acoustic scattering modulation from a moving rough sea surface is studied based on integral equation and parabolic equation.And with the principles of grating and constructive interference,the mechanism of this acoustic scattering modulation is explained.The periodicity of the interference of moving rough sea surface will lead to the interference of the scattering field at a series of discrete angles,which will form comb-like and frequency-shift characteristics on the intensity and the frequency spectrum of the acoustic scattering field,respectively,which is a high-order Bragg scattering phenomenon.Unlike the conventional Doppler effect,the frequency shifts of the Bragg scattering phenomenon are multiples of the undulating sea surface frequency and are independent of the incident sound wave frequency.Therefore,even if a low-frequency underwater acoustic field is incident,it will produce obvious frequency shifts.Moreover,under the action of ideal sinusoidal waves,swells,fully grown wind waves,unsteady wind waves,or mixed waves,different moving rough sea surfaces create different acoustic scattering processes and possess different frequency shift characteristics.For the swell wave,which tends to be a single harmonic wave,the moving rough sea surface produces more obvious high-order scattering and frequency shifts.The same phenomena are observed on the sea surface under fully grown wind waves,however,the frequency shift slightly offsets the multiple peak frequencies of the wind wave spectrum.Comparing with the swell and fully-grown wind waves,the acoustic scattering and frequency shift are not obvious for the sea surface under unsteady wind waves. 展开更多
关键词 high-order Bragg scattering frequency shift low-frequency acoustic field moving rough sea surface
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Symmetry Reductions, Integrability and Solitary Wave Solutions to High-Order Modified Boussinesq Equations with Damping Term 被引量:2
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作者 YAN ZhenYa XIE FuDing ZHANG HongQing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第7期1-6,共6页
Both the direct method due to Clarkson and Kruskal and the improved direct method due to Lou are extended to reduce the high-order modified Boussinesq equation with the damping term (HMBEDT) arising in the general Fer... Both the direct method due to Clarkson and Kruskal and the improved direct method due to Lou are extended to reduce the high-order modified Boussinesq equation with the damping term (HMBEDT) arising in the general Fermi-Pasta-Ulam model. As a result, several types of similarity reductions are obtained. It is easy to show that the nonlinear wave equation is not integrable under the sense of AblowRz's conjecture from the reduction results obtained. In addition, kink-shaped solitary wave solutions, which are of important physical significance, are found for HMBEDT based on the obtained reduction equation. 展开更多
关键词 MODIFIED BOUSSINESQ EQUATION with the damping term nonlinear evolution equation symmetry reduction integrability SOLITARY wave solution
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High-order harmonic generation of ZnO crystals in chirped and static electric fields
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作者 张玲玉 何永林 +5 位作者 谢卓璇 高芳艳 徐清芸 葛鑫磊 罗香怡 郭静 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期335-343,共9页
High harmonic generation in ZnO crystals under chirped single-color field and static electric field are investigated by solving the semiconductor Bloch equation(SBE). It is found that when the chirp pulse is introduce... High harmonic generation in ZnO crystals under chirped single-color field and static electric field are investigated by solving the semiconductor Bloch equation(SBE). It is found that when the chirp pulse is introduced, the interference structure becomes obvious while the harmonic cutoff is not extended. Furthermore, the harmonic efficiency is improved when the static electric field is included. These phenomena are demonstrated by the classical recollision model in real space affected by the waveform of laser field and inversion symmetry. Specifically, the electron motion in k-space shows that the change of waveform and the destruction of the symmetry of the laser field lead to the incomplete X-structure of the crystal-momentum-resolved(k-resolved) inter-band harmonic spectrum. Furthermore, a pre-acceleration process in the solid four-step model is confirmed. 展开更多
关键词 high-order harmonic generation the semiconductor Bloch equation k-resolved inter-band harmonic spectrum four-step semiclassical model
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Arbitrary High-Order Fully-Decoupled Numerical Schemes for Phase-Field Models of Two-Phase Incompressible Flows
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作者 Ruihan Guo Yinhua Xia 《Communications on Applied Mathematics and Computation》 EI 2024年第1期625-657,共33页
Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple the... Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple these two equations.One popular and efficient strategy is to add an explicit stabilizing term to the convective velocity in the phase-field equation to decouple them.The resulting schemes are only first-order accurate in time,and it seems extremely difficult to generalize the idea of stabilization to the second-order or higher version.In this paper,we employ the spectral deferred correction method to improve the temporal accuracy,based on the first-order decoupled and energy-stable scheme constructed by the stabilization idea.The novelty lies in how the decoupling and linear implicit properties are maintained to improve the efficiency.Within the framework of the spatially discretized local discontinuous Galerkin method,the resulting numerical schemes are fully decoupled,efficient,and high-order accurate in both time and space.Numerical experiments are performed to validate the high-order accuracy and efficiency of the methods for solving phase-field models of two-phase incompressible flows. 展开更多
关键词 Two-phase incompressible flows Fully-decoupled high-order accurate Linear implicit Spectral deferred correction method Local discontinuous Galerkin method
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Lexical Characteristics and Translation Strategies of Rubber and Plastic Industry Terms
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作者 XIA Xiao-yu 《Journal of Literature and Art Studies》 2024年第10期861-866,共6页
As a key part of the manufacturing industry,the rubber and plastic industry is widely used in a variety of fields such as automotive manufacturing,construction materials,and electronics.With technological innovation,g... As a key part of the manufacturing industry,the rubber and plastic industry is widely used in a variety of fields such as automotive manufacturing,construction materials,and electronics.With technological innovation,global economic growth and infrastructure construction driving the demand for rubber and plastic materials,rubber and plastic materials play an important role in various fields,and accurate translation of the industry’s terminology is also crucial for international communication.The purpose of this paper is to explore in depth the lexical features of rubber and plastic industry terminology,including strong specialization,specialization of common vocabulary,and diversity of word formation.In view of these lexical features,relevant Chinese translation strategies are discussed to ensure the accuracy,specialization and comprehensibility of the translation of rubber and plastic industry terms. 展开更多
关键词 rubber and plastic industry terms lexical feature translation strategy
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High-Order Soliton Solutions and Hybrid Behavior for the (2 + 1)-Dimensional Konopelchenko-Dubrovsky Equations
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作者 Xingying Li Yin Ji 《Journal of Applied Mathematics and Physics》 2024年第7期2452-2466,共15页
In this paper, the evolutionary behavior of N-solitons for a (2 + 1)-dimensional Konopelchenko-Dubrovsky equations is studied by using the Hirota bilinear method and the long wave limit method. Based on the N-soliton ... In this paper, the evolutionary behavior of N-solitons for a (2 + 1)-dimensional Konopelchenko-Dubrovsky equations is studied by using the Hirota bilinear method and the long wave limit method. Based on the N-soliton solution, we first study the evolution from N-soliton to T-order (T=1,2) breather wave solutions via the paired-complexification of parameters, and then we get the N-order rational solutions, M-order (M=1,2) lump solutions, and the hybrid behavior between a variety of different types of solitons combined with the parameter limit technique and the paired-complexification of parameters. Meanwhile, we also provide a large number of three-dimensional figures in order to better show the degeneration of the N-soliton and the interaction behavior between different N-solitons. 展开更多
关键词 Konopelchenko-Dubrovsky Equations Hirota Bilinear Method M-Order Lump Solutions high-order Hybrid Solutions Interaction Behavior
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Generation of tunable high-order Laguerre– Gaussian petal-like modes from a mid-infrared optical vortex parametric oscillator
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作者 Yuxia Zhou Xining Yang +4 位作者 Jianqiang Ye Yuanyuan Ma Ying Wan Jianxiang Wen Taximaiti Yusufu 《Advanced Photonics Nexus》 2024年第3期113-119,共7页
High-order Laguerre–Gaussian(LG)petal-like beams have become a topic of significant interest due to their potential application in next-generation optical trapping,quantum optics,and materials processing technologies... High-order Laguerre–Gaussian(LG)petal-like beams have become a topic of significant interest due to their potential application in next-generation optical trapping,quantum optics,and materials processing technologies.In this work,we demonstrate the generation of high-order LG beams with petal-like spatial profiles and tunable orbital angular momentum(OAM)in the mid-infrared wavelength region.These beams are generated using idler-resonant optical parametric oscillation(OPO)in a KTiOAsO_(4)(KTA)crystal.By adjusting the length of the resonant cavity,the OAM of the mid-infrared idler field can be tuned and we demonstrate tuning in the range of 0 to10.When using a maximum pump energy of 20.2 mJ,the maximum output energy of high-order modes LG_(0.45),LG_(0.48),and LG_(0.410) were 0.8,0.53,and 0.46 mJ,respectively.The means by which high-order LG modes with petal-like spatial profiles and tunable OAM were generated from the OPO is theoretically modeled by examining the spatial overlap efficiency of the beam waists of the pump and resonant idler fields within the center of the KTA crystal.The methodology presented in this work offers a simple and flexible method to wavelength-convert laser emission and generate high-order LG modes. 展开更多
关键词 high-order Laguerre-Gaussian petal-like modes optical parametric oscillator nonlinear optics KTiOAsO_(4) optical vortices.
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On the conceptual metaphor of color terms: A typological view 被引量:1
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作者 宋宏 《Sino-US English Teaching》 2009年第1期23-25,共3页
In different languages and cultures, color terms usually indicate their specific cultural concepts and metaphorical implicature. This paper makes a typological study on the universality and relativity of the Conceptua... In different languages and cultures, color terms usually indicate their specific cultural concepts and metaphorical implicature. This paper makes a typological study on the universality and relativity of the Conceptual Metaphors (CM) of color terms in different languages. It attempts to explore the cognitive differences and similarities in the process of categorization and metaphorization of color terms of oriental and western peoples. It proposes that the CM system of color terms is determined by the interactivity of three factors as neurophysiologic mechanisms, general cognitive psychological mechanisms and socio-cultural selective mechanisms. The CM of color terms in different languages carry their specific cognitive characteristics and cultural values, and reflect self-similarity of the language and culture. 展开更多
关键词 color terms conceptual metaphor COGNITION language typology
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On E-C Translation of Proprietary Business Brand Terms
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作者 贾俊敏 赵万里 《海外英语》 2015年第13期128-129,共2页
An excellent translation of proprietary business brand terms is more important in international trade.Diverse cultural backgrounds and purposiveness of products are the most influential factors.The research tries to a... An excellent translation of proprietary business brand terms is more important in international trade.Diverse cultural backgrounds and purposiveness of products are the most influential factors.The research tries to analyze the elements of cultural background and aims of products that affect E-C translation of proprietary business brand terms by descriptive study method and experience summary method,and then to provide methods to overcome these difficulties. 展开更多
关键词 BUSINESS BRAND terms CULTURAL BACKGROUND purposiveness translation strategies
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探析新版国际贸易术语解释通则(Incoterms■2020) 被引量:6
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作者 赵静敏 《对外经贸》 2020年第5期21-24,共4页
了解国际贸易术语解释规则的修订历程和及时掌握国际贸易术语解释通则的最新变化,对外贸企业进行国际贸易合同条款磋商和签订进出口合同至关重要。通过梳理国际商会(ICC)对国际贸易术语解释规则的历次更新修改,并对最新颁布和生效的《2... 了解国际贸易术语解释规则的修订历程和及时掌握国际贸易术语解释通则的最新变化,对外贸企业进行国际贸易合同条款磋商和签订进出口合同至关重要。通过梳理国际商会(ICC)对国际贸易术语解释规则的历次更新修改,并对最新颁布和生效的《2020年国际贸易术语解释通则》的实质性变化的探讨,指出外贸企业在签订贸易合同时如何正确选择和使用恰当的贸易术语所应关注的事项,以避免贸易纠纷,有效控制风险。 展开更多
关键词 Incoterms■2020 商业惯例 贸易术语
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《Incoterms 2010》的变化及使用 被引量:2
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作者 王晓辉 《嘉兴学院学报》 2012年第1期67-70,共4页
《Incoterms 2010》首次正式明确贸易术语同时适用于国际、国内贸易,贸易术语的设置顺应了运输方式的发展,各项内容表述更加清楚,对贸易术语进行了重新分类。使用时必须注意尽快熟悉新通则的相关规定,重视非海运贸易术语的使用,可以通... 《Incoterms 2010》首次正式明确贸易术语同时适用于国际、国内贸易,贸易术语的设置顺应了运输方式的发展,各项内容表述更加清楚,对贸易术语进行了重新分类。使用时必须注意尽快熟悉新通则的相关规定,重视非海运贸易术语的使用,可以通过合同对贸易术语的盲点进行弥补,不要轻易做出与通则相悖的修改。 展开更多
关键词 INCOterms 2010 贸易术语 合理选择
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Incoterms2000与Incoterms1990贸易术语的比较研究 被引量:1
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作者 李大鹏 罗士菊 《重庆商学院学报》 2001年第2期28-30,共3页
本文首先探讨了国际商务修订 INCOTERMS的原因和原则 ,然后详细地对《 Incoterms2000》与《 Incoterms1990》进行了比较分析。
关键词 《Incoterms2000》《Inctoerms1990》 贸易术语 对比研究
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An Analysis of Different Addressing Terms in High Context Communication and Low Context Communication from the Perspective of Frame Theory
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作者 刘鹏丽 《海外英语》 2014年第14期44-45,共2页
Within the scope of human beings, some addressing terms are similar. However, different addressing terms still exist,which are influenced by the background of high context communication or low context communication. A... Within the scope of human beings, some addressing terms are similar. However, different addressing terms still exist,which are influenced by the background of high context communication or low context communication. A good example is that Chinese traditional culture, a typical instance of high context communication, puts much emphasis on etiquette, which is represented in addressing terms as more complex and definite; In western, with the background of low context communication, every individual is more equal and they address each other more generally and much simpler. This paper tries to explore the addressing terms both in Chinese and in English from the perspective of frame theory. 展开更多
关键词 ADDRESSING terms titles HCC LCC
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A Brief Analysis of The Holy Bible's Impact on the Connotative Meanings of Color Terms and their Applications in Literatures
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作者 赵妮莎 《海外英语》 2012年第1X期274-276,281,共4页
The Holy Bible,as one of major sources of Western Culture,has a great influence on the Christian culture and Christian thoughts.Because language is a carrier of culture,the English study will be water without a source... The Holy Bible,as one of major sources of Western Culture,has a great influence on the Christian culture and Christian thoughts.Because language is a carrier of culture,the English study will be water without a source and a tree without roots if we ignore The Holy Bible which is the core of Christianity.To study English demands not only grammar and vocabulary,but also the culture behind the language.A brief analysis of connotative meanings of color terms,which are influenced by The Holy Bible and applied in literatures,will be given,in order to offer some help to English learners to know the connotations of color terms better,to understand literatures more profoundly and to have a general feeling about the impact which The Holy Bible has on language. 展开更多
关键词 The Holy Bible COLOR terms connotative MEANINGS LI
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On Chinese-English Translation of Disease and Syndrome Terms in Shang Han Lun from the Perspective of Functional Equivalence Theory
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作者 喻惠芳 倪天鸣 《海外英语》 2015年第19期148-149,155,共3页
Shang Han Lun is one of the most famous and important traditional medical books in China,so many translation versions of it have emerged.Based on the comparison of examples taken from two of these translation versions... Shang Han Lun is one of the most famous and important traditional medical books in China,so many translation versions of it have emerged.Based on the comparison of examples taken from two of these translation versions,Young Jie De ' s Shang Han Lun Explained and Huang Hai s Introduction to Treatise on Exogenous Febrile Disease,the paper points out that Nida s Functional Equivalence Theory provides a new idea for the translation of Disease and Syndrome Terms in TCM that literal translation,liberal translation and transliteration can be adopted appropriately to make readers of translation versions understand TCM accurately and easily. 展开更多
关键词 translation DISEASE and SYNDROME term Shang HAN Lun Functional EQUIVALENCE
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关于Trade Terms“象征性交货”教学的探讨
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作者 李京福 《中国电子商务》 2014年第23期126-126,128,共2页
Trade Terms是国际贸易实务的基础知识,在实务操作中占有重要地位。但是,在常用贸易术语条件下,实际上采用的是一种区别于日常的实际交货的象征性交货方式,即卖方凭单交货、买方凭单付款。学生对此不易理解,主要是由于交货方式的... Trade Terms是国际贸易实务的基础知识,在实务操作中占有重要地位。但是,在常用贸易术语条件下,实际上采用的是一种区别于日常的实际交货的象征性交货方式,即卖方凭单交货、买方凭单付款。学生对此不易理解,主要是由于交货方式的特殊性、缺乏国际货运保险知识、孤立地理解交货方式等原因所造成。因此,本文通过采取案例分析深化理解、补充国际货运保险知识、总体把握外贸介同、深化理解风险转移点等方法,以期帮助初学者正确理解和接受这种特殊的交货方式。 展开更多
关键词 TRADE terms 交货方式 风险
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