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Relaxed Stability Criteria for Time-Delay Systems:A Novel Quadratic Function Convex Approximation Approach
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作者 Shenquan Wang Wenchengyu Ji +2 位作者 Yulian Jiang Yanzheng Zhu Jian Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期996-1006,共11页
This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By i... This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By introducing two adjustable parameters and two free variables,a novel convex function greater than or equal to the quadratic function is constructed,regardless of the sign of the coefficient in the quadratic term.The developed lemma can also be degenerated into the existing quadratic function negative-determination(QFND)lemma and relaxed QFND lemma respectively,by setting two adjustable parameters and two free variables as some particular values.Moreover,for a linear system with time-varying delays,a relaxed stability criterion is established via our developed lemma,together with the quivalent reciprocal combination technique and the Bessel-Legendre inequality.As a result,the conservatism can be reduced via the proposed approach in the context of constructing Lyapunov-Krasovskii functionals for the stability analysis of linear time-varying delay systems.Finally,the superiority of our results is illustrated through three numerical examples. 展开更多
关键词 equivalent reciprocal combination technique quadratic function convex approximation approach STABILITY timevarying delay
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Charge self-consistent dynamical mean field theory calculations incombination with linear combination of numerical atomic orbitalsframework based density functional theory
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作者 Xin Qu Peng Xu +6 位作者 Zhiyong Liu Jintao Wang Fei Wang Wei Huang Zhongxin Li Weichang Xu Xinguo Ren 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期62-69,共8页
We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implemen... We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implementedthe charge self-consistent DFT+DMFT formalism by interfacing a full-potential all-electron DFT code with threehybridization expansion-based continuous-time quantum Monte Carlo impurity solvers.The benchmarks on several 3d,4fand 5f strongly correlated electron systems validated our formalism and implementation.Furthermore,within the LCANOframework,our formalism is general and the code architecture is extensible,so it can work as a bridge merging differentLCNAO DFT packages and impurity solvers to do charge self-consistent DFT+DMFT calculations. 展开更多
关键词 dynamical mean field theory density functional theory strongly correlated electrons
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Coefficient Estimates for a Subclass of Bi-univalent Strongly Quasi-starlike Functions 被引量:2
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作者 LI ZONG-TAO GUO DONG Ji You-qing 《Communications in Mathematical Research》 CSCD 2018年第4期303-308,共6页
The aim of this paper is to establish the Fekete-Szego inequality for a subclass of bi-univalent strongly quasi-starlike functions which is defined in the open unit disk. Furthermore, the coefficients a2 and a3 for fu... The aim of this paper is to establish the Fekete-Szego inequality for a subclass of bi-univalent strongly quasi-starlike functions which is defined in the open unit disk. Furthermore, the coefficients a2 and a3 for functions in this new subclass are estimated. 展开更多
关键词 bi-univalent function bi-univalent strongly quasi-starlike function coefficient estimate SUBORDINATION
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On the dielectric response function and dispersion relation in strongly coupled magnetized dusty plasmas 被引量:1
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作者 M Shahmansouri N Khodabakhshi 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期465-470,共6页
Using the generalized viscoelastic fluid model, we derive the dielectric response function in a strongly coupled dusty magnetoplasma which reveals two different dust acoustic(DA) wave modes in the hydrodynamic and k... Using the generalized viscoelastic fluid model, we derive the dielectric response function in a strongly coupled dusty magnetoplasma which reveals two different dust acoustic(DA) wave modes in the hydrodynamic and kinetic limits. The effects of the strong interaction of dust grains and the external magnetic on these DA modes, as well as on the shear wave are examined. It is found that both the real and imaginary parts of DA waves are significantly modified in strongly coupled dusty magnetoplasmas. The implications of our results to space and laboratory dusty plasmas are briefly discussed. 展开更多
关键词 dusty plasma strongly coupled plasma MAGNETOPLASMA dielectric response function
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Measurement of air kerma rate and ambient dose equivalent rate using the G(E) function with hemispherical CdZnTe detector
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作者 Ping Huang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期71-77,共7页
Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation dete... Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation detectors such as cerium chloride doped with lanthanum bromide(LaBr_3(Ce)), thallium doped with cesium iodide(sI(Tl)), thallium doped with sodium iodide(NaI(Tl)),and high-purity germanium(HPGe) primarily use the spectroscopy-dose rate function(G(E)) to achieve the accurate measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)). However, the spectroscopy-dose rate function has been rarely measured for a CZT detector. In this study, we performed spectrum measurement using a hemispherical CZT detector in a radiation protection standards laboratory. The spectroscopy-dose rate function G(E) of the CZT detector was calculated using the least-squares method combined with the standard dose rate at the measurement position. The results showed that the hemispherical CZT detector could complete the measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)) by using the G(E) function at energies between 48 keV and 1.25 MeV, and the relative intrinsic errors were, respectively, controlled within ± 2. 3 and ± 2. 1%. 展开更多
关键词 CDZNTE Spectroscopy-dose RATE G(E) function Air kerma RATE AMBIENT DOSE equivalent RATE Relative intrinsic error
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Comparative study of functional optical zone:small incision lenticule extraction versus femtosecond laser assisted excimer laser keratomileusis 被引量:2
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作者 Yao-Wen Song Meng-Fan Cui +3 位作者 Yi Feng Min Qu Yan Gao Rui He 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第2期238-244,共7页
AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential as... AIM:To investigate the size of functional optical zone(FOZ)after small incision lenticule extraction(SMILE)versus femtosecond laser assisted excimer laser keratomileusis(FS-LASIK)for myopia correction and potential associated factors for FOZ.METHODS:A total of 133 patients who received corneal refractive surgery in our hospital between November 2018 and July 2021 were retrospectively enrolled.There were 63 patients(123 eyes)in SMILE group and 70patients(139 eyes)in FS-LASIK group.The size of FOZ was measured using Pentacam 3-dementional anterior segment analyzer before and 3mo after surgery,so as to analyze postoperative achieved functional optical zone(AFOZ)and its contributing parameters.RESULTS:When planned functional optical zone(PFOZ)was 6.5 mm for both groups,AFOZ was 1.45±0.27 and 1.67±0.25 mm smaller than preoperative FOZ in SMILE group and FS-LASIK group 3mo after surgery.AFOZ in SMILE group was significantly larger than that in FS-LASIK group(P<0.001).Variation of FOZ was negatively correlated with preoperative spherical equivalent(SE)and positively correlated with variation of mean keratometry value(△Km),variation of spherical aberration(△SA),and variation of Q-value(△Q,all P<0.001)in both groups.Multiple variable linear regression equations were△FOZ=1.354-0.1×pre-SE+0.336×△Q+1.462×△SA in SMILE group and△FOZ=1.512+0.137×△Q+0.468×△SA in FS-LASIK group.CONCLUSION:AFOZ is significantly smaller than preoperative FOZ in both SMILE and FS-LASIK groups.With the same PFOZ,larger AFOZ is achieved in SMILE group than in FS-LASIK group. 展开更多
关键词 functional optical zone small incision lenticule extraction femtosecondlaser assisted excimer laser keratomileusis spherical equivalent spherical aberration
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Test of Generating Function and Estimation of Equivalent Radius in Some Weapon Systems and Its Stochastic Simulation
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作者 Famei Zheng 《Applied Mathematics》 2011年第12期1546-1550,共5页
We discuss three-dimensional uniform distribution and its property in a sphere;give a method of assessing the tactical and technical indices of cartridge ejection uniformity in some type of weapon systems. Meanwhile w... We discuss three-dimensional uniform distribution and its property in a sphere;give a method of assessing the tactical and technical indices of cartridge ejection uniformity in some type of weapon systems. Meanwhile we obtain the test of generating function and the estimation of equivalent radius. The uniformity of distribution is tested and verified with ω2 test method on the basis of stochastic simulation example. 展开更多
关键词 UNIFORM Distribution in a SPHERE WEAPON Systems GENERATING function equivalent RADIUS Stochastic Simulation
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New Result for Strongly Starlike Functions
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作者 R. O. Ayinla T. O. Opoola 《Applied Mathematics》 2017年第3期324-328,共5页
In this paper, using Salagean differential operator, we define and investigate a new subclass of univalent functions . We also establish a characterization property for functions belonging to the class .
关键词 strongly STARLIKE functionS strongly CONVEX functionS Salagean Differential OPERATOR
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Evaluation of strongly singular domain integrals for internal stresses in functionally graded materials analyses using RIBEM
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作者 Hai-Feng Peng Jian Liu +1 位作者 Qiang-Hua Zhu Ch.Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期917-926,共10页
An accurate evaluation of strongly singular domain integral appearing in the stress representation formula is a crucial problem in the stress analysis of functionally graded materials using boundary element method.To ... An accurate evaluation of strongly singular domain integral appearing in the stress representation formula is a crucial problem in the stress analysis of functionally graded materials using boundary element method.To solve this problem,a singularity separation technique is presented in the paper to split the singular integral into regular and singular parts by subtracting and adding a singular term.The singular domain integral is transformed into a boundary integral using the radial integration method.Analytical expressions of the radial integrals are obtained for two commonly used shear moduli varying with spatial coordinates.The regular domain integral,after expressing the displacements in terms of the radial basis functions,is also transformed to the boundary using the radial integration method.Finally,a boundary element method without internal cells is established for computing the stresses at internal nodes of the functionally graded materials with varying shear modulus. 展开更多
关键词 Stress integral equations functionally graded materials strongly singular domain integral Singularity separation technique Radial integration method
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Strongly Generalized Convex Fuzzy-Valued Function and Its Application in Fuzzy Optimization
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作者 BAI Yu-juan LIU Kun ZHANG Chen 《Chinese Quarterly Journal of Mathematics》 2020年第4期370-387,共18页
Based on the ordering of fuzzy numbers proposed by Goetschel and Voxman,the representations and some properties of strongly preinvex fuzzy-valued function are defined and obtained, several new concepts of strongly mon... Based on the ordering of fuzzy numbers proposed by Goetschel and Voxman,the representations and some properties of strongly preinvex fuzzy-valued function are defined and obtained, several new concepts of strongly monotonicities fuzzy functions are introduced, the relationship among the strongly preinvex, strongly invex and monotonicities under some suitable and appropriate conditions is established and a necessary condition for strongly pseudoinvex functions is given. As an application, the conditions of local optimal solution and global optimal solution in the mathematical programming problem are discussed. 展开更多
关键词 Fuzzy-number-valued functions strongly generalized convexity Fuzzy optimization
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A METHOD FOR CALCULATING TRANSIENT FUNCTIONS OF EQUIVALENT DETERMINISTIC INPUT
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《Chinese Journal of Aeronautics》 SCIE EI CAS 1988年第2期98-104,共7页
In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-... In the present paper the analytical formulas for calculating the equivalent deterministic transients for multivariable cross correlated random processes are developed.The formulas permit the determination of the Root-mean-square of the responses of a linear time-invariant system to stationary multiple random inputs in the time domain.The method is applicable in the study of flight of airplanes in atmospheric turbulence and is also useful for general engineering applications of stochastc processes control. 展开更多
关键词 A METHOD FOR CALCULATING TRANSIENT functionS OF equivalent DETERMINISTIC INPUT
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A Unified Approach to the Thermodynamics and Quantum Scaling Functions of One-Dimensional Strongly Attractive SU(w) Fermi Gases
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作者 余毅聪 管习文 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期41-46,共6页
We present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with SU(w) symmetry. These physical quantities ... We present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with SU(w) symmetry. These physical quantities provide a rigorous understanding on a universality class of quantum criticality characterized by the critical exponents z = 2 and correlation length exponent v= 1/2. Such a universality class of quantum criticality can occur when the Fermi sea of one branch of charge bound states starts to fill or becomes gapped at zero temperature. The quantum critical cone can be determined by the double peaks in specific heat, which serve to mark two crossover temperatures fanning out from the critical point. Our method opens to further study on quantum phases and phase transitions in strongly interacting fermions with large SU ( w) and non-SU ( w ) symmetries in one dimension. 展开更多
关键词 A Unified Approach to the Thermodynamics and Quantum Scaling functions of One-Dimensional strongly Attractive SU
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Some Integral Inequalities of Simpson Type for Strongly Extended s-Convex Functions
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作者 Yixuan Sun Hongping Yin 《Advances in Pure Mathematics》 2016年第11期745-753,共9页
The main purpose of this survey paper is to point out some very recent developments on Simpson’s inequality for strongly extended s-convex function. Firstly, the concept of strongly extended s-convex function is intr... The main purpose of this survey paper is to point out some very recent developments on Simpson’s inequality for strongly extended s-convex function. Firstly, the concept of strongly extended s-convex function is introduced. Next a new identity is also established. Finally, by this identity and H?lder’s inequality, some new Simpson type for the product of strongly extended s-convex function are obtained. 展开更多
关键词 Simpson Type Inequality Integral Identity strongly Extended s-Convex function
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基于正弦函数拟合的高动态捷联惯导姿态更新算法 被引量:1
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作者 路永乐 杨杰 +3 位作者 孙旗 罗毅 肖轩 刘宇 《中国惯性技术学报》 EI CSCD 北大核心 2024年第1期1-7,共7页
为提高捷联惯导在高动态条件下的姿态解算精度,基于等效旋转矢量泰勒级数展开法,提出一种基于正弦函数拟合的高动态捷联惯导姿态更新算法。以正弦函数拟合载体运动角速度,考虑Bortz方程高阶项的影响,对陀螺角增量表示的旋转矢量进行泰... 为提高捷联惯导在高动态条件下的姿态解算精度,基于等效旋转矢量泰勒级数展开法,提出一种基于正弦函数拟合的高动态捷联惯导姿态更新算法。以正弦函数拟合载体运动角速度,考虑Bortz方程高阶项的影响,对陀螺角增量表示的旋转矢量进行泰勒六阶展开,对比旋转矢量不同形式表达式求得误差补偿系数。在MATLAB平台上,以圆锥运动与大角速率转动并存环境作为仿真条件,对所提算法与传统算法进行对比仿真分析。仿真结果表明,在小半锥角低频圆锥运动伴随高速角速率转动情况下,所提算法性能较好,当半锥角为0.5°、角频率为2.26πrad/s、常值角速率为5.30 rad/s、姿态解算周期为0.02 s时,所提正弦函数拟合三子样旋转矢量算法与传统扩展形式频率级数/显示频率三子样圆锥算法相比误差降低了2个数量级。 展开更多
关键词 捷联姿态算法 高动态 正弦函数拟合 等效旋转矢量
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建筑空间最优节能设计模型仿真研究 被引量:1
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作者 周忠长 刘集成 《计算机仿真》 2024年第3期528-532,共5页
由于建筑结构主体较多,空间能耗难以合并控制,导致目前建筑空间能源耗用量较大。为此,构建基于等效转换法的建筑空间最优节能模型,并对其仿真研究。提出建筑总体能耗作为初始优化的“尺度”概念,该尺度为建筑空间的外墙、内墙、屋顶、... 由于建筑结构主体较多,空间能耗难以合并控制,导致目前建筑空间能源耗用量较大。为此,构建基于等效转换法的建筑空间最优节能模型,并对其仿真研究。提出建筑总体能耗作为初始优化的“尺度”概念,该尺度为建筑空间的外墙、内墙、屋顶、分户楼板以及门窗等参数,求解这些尺度的最佳标准值。采用等效转换法计算在节能条件下所能接受的最大能耗范围。在此基础上,以上述范围值为约束条件,建立控制函数。将上述提到标准尺度值和最大能耗范围设置为最优解,建立最优节能设计模型,设定温差调节因子,对每一次室内外温差实施有效调节控制,保证建筑体参数符合最佳能耗范围。仿真结果证明,所提方法对冬季采暖和夏季制冷的能耗控制效果均较佳,节能效果最优且算法收敛性高,鲁棒性较好。 展开更多
关键词 建筑空间 最优节能设计 等效转换 控制函数 调节因子
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等价无穷小的若干性质
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作者 涂振坤 宁荣健 周江涛 《大学数学》 2024年第5期74-80,共7页
给出了反函数、参数方程确定的函数以及隐函数等价无穷小的若干性质,丰富了等价无穷小的理论,有一定的理论价值和应用价值.
关键词 反函数 参数方程确定的函数 隐函数 等价无穷小
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基于边缘约束与范数比值的图像盲复原
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作者 赵小强 王涛 《兰州理工大学学报》 CAS 北大核心 2024年第1期76-83,共8页
针对现有的研究方法对运动所引起的模糊图像进行复原时效果欠佳的问题,提出一种基于边缘约束与范数比值的图像盲复原算法.该算法首先对退化图像的边缘进行约束,得到图像的强边缘结构,提高了点扩散函数估计的准确率;然后对要估计的清晰... 针对现有的研究方法对运动所引起的模糊图像进行复原时效果欠佳的问题,提出一种基于边缘约束与范数比值的图像盲复原算法.该算法首先对退化图像的边缘进行约束,得到图像的强边缘结构,提高了点扩散函数估计的准确率;然后对要估计的清晰图像构造范数比值的稀疏惩罚约束项,并将得到的强边缘信息与构造的范数比值惩罚约束项进行结合用于指引点扩散函数的复原;在对点扩散函数进行复原时,由粗到细多尺度交替迭代估计点扩散函数,使得迭代出的最大尺度更加精确;最后对图像进行非盲解卷积求解,使其复原.该算法将退化图像的边缘信息与构造的范数比值惩罚约束项进行结合指导点扩散函数的复原,可以抑制图像在复原过程中产生的大量伪迹.实验结果表明,该算法对恢复图像边缘细节具有很好的效果,可以得到优质的复原图像. 展开更多
关键词 图像盲复原 多尺度 范数比值 强边缘 点扩散函数
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吐鲁番市土地利用转型及生态服务功能交叉敏感性
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作者 冶建明 谢斯琦 《草业科学》 CAS CSCD 北大核心 2024年第9期2164-2180,共17页
厘清吐鲁番市2000-2018年土地利用转型及生态服务价值时空演变特征,探讨生态服务价值与地类转型的相互关系,可为合理规划区域土地资源的同时实现生态服务功能的改善和提升提供依据。基于5期土地利用遥感影像数据,采用土地利用动态变化... 厘清吐鲁番市2000-2018年土地利用转型及生态服务价值时空演变特征,探讨生态服务价值与地类转型的相互关系,可为合理规划区域土地资源的同时实现生态服务功能的改善和提升提供依据。基于5期土地利用遥感影像数据,采用土地利用动态变化模型及修正后的生态服务价值系数,结合改进的交叉敏感性系数模型分析生态服务价值对土地利用转型的敏感程度。结果表明,1)吐鲁番市以草地、未利用地及耕地等地类为主,建设用地、耕地持续扩张,水域、草地不断减少,其中以草地与水域、耕地及未利用地之间的转型为主;2)研究时段内生态系统服务价值呈现“先减后增再减”的动态变化趋势,高值区主要分布于北部山区以及中部绿洲平原区域;3)生态服务功能对林地、水域、草地及未利用地向其他地类转型敏感性响应程度较高,草地、建设用地与未利用地转型的高敏感区分布较广,未利用地与水域、建设用地间转型的低敏感区分布较广。区域应加强对水域、林地、草地等生态系统的保护,在发展经济建设的同时注重合理规划土地资源及生态环境质量的提升。 展开更多
关键词 土地转型 生态服务功能 生态服务价值 当量因子 交叉敏感性 时空演变 吐鲁番市
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功能对等理论视角下中国文化负载词的翻译研究——以2017~2022年大学英语四级段落翻译为例
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作者 杨永凤 《泰州职业技术学院学报》 2024年第4期43-46,共4页
自十八大报告提出“增强文化自信”以来,中国传统文化受到了高度关注。四级英语考试中大量中国文化负载词的出现体现了这一时代的发展和要求。文章基于功能对等理论,以2017年6月到2022年12月的四级翻译真题为研究文本,根据分类采用音译... 自十八大报告提出“增强文化自信”以来,中国传统文化受到了高度关注。四级英语考试中大量中国文化负载词的出现体现了这一时代的发展和要求。文章基于功能对等理论,以2017年6月到2022年12月的四级翻译真题为研究文本,根据分类采用音译、直译、意译等方法翻译出其文化内涵和意义,从而提高大学生英语四级考试汉译英的能力,实现文化的有效传播,提高民族文化自信。 展开更多
关键词 功能对等理论 中国文化负载词 大学英语四级 翻译方法
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《寻乌调查》“子”尾名词英译的信息对等与缺失
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作者 曾繁健 刘丹婷 《宜春学院学报》 2024年第1期82-87,共6页
方言蕴含着深厚的文化气息,中西方文化的不同,给方言英译也带了难题。为了促进方言英译和传播,本文以汤若杰(Thompson,Roger R)的《寻乌调查》英译本为研究对象,尤金·奈达的功能对等理论为指导,借助NVivo质性研究软件,探析其中客... 方言蕴含着深厚的文化气息,中西方文化的不同,给方言英译也带了难题。为了促进方言英译和传播,本文以汤若杰(Thompson,Roger R)的《寻乌调查》英译本为研究对象,尤金·奈达的功能对等理论为指导,借助NVivo质性研究软件,探析其中客家方言“子”尾名词英译信息对等与缺失。为了实现“子”尾名词英译的信息对等,译者应首先分析汉语“子”尾的功能,才能够准确无误地理解其蕴含的信息,进一步实现语义和文化信息对等。研究发现,《寻乌调查》英译本中关于“子”尾词的英译绝大多数实现了信息对等,让原文读者和译文读者之间能够最大程度地接收到相同的信息;少部分由于译者汤若杰未能很好地理解到“子”尾功能,导致译文信息存在部分的缺失。 展开更多
关键词 《寻乌调查》 “子”尾功能 英译 信息对等 信息缺失
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