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An Exploration of Interpersonal Meanings in Advertising Discourse from Functional Grammar Perspective 被引量:1
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作者 刘瑜 樊燕龙 《Sino-US English Teaching》 2007年第1期40-45,共6页
Interpersonal function is one of the three metafunctions of language. This paper investigates the interpersonal meanings in Chinese cosmetic advertising discourse from mood, modality and appraise the three aspects. Ba... Interpersonal function is one of the three metafunctions of language. This paper investigates the interpersonal meanings in Chinese cosmetic advertising discourse from mood, modality and appraise the three aspects. Based on an exploratory study of data of six typical Chinese cosmetic advertising discourses, the paper claims that the distribution of mood and modality has close link with the interpersonal meaning in advertising. The Functional Grammar and Appraisal System help to reveal the interpersonal meanings of the discourse concerned. 展开更多
关键词 interpersonal meaning functional grammar appraisal system
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基于改进K-means的局部离群点检测方法 被引量:7
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作者 周玉 夏浩 +1 位作者 岳学震 王培崇 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第4期66-77,共12页
离群点检测任务是指检测与正常数据在特征属性上存在显著差异的异常数据。大多数基于聚类的离群点检测方法主要从全局角度对数据集中的离群点进行检测,而对局部离群点的检测性能较弱。基于此,本文通过引入快速搜索和发现密度峰值方法改... 离群点检测任务是指检测与正常数据在特征属性上存在显著差异的异常数据。大多数基于聚类的离群点检测方法主要从全局角度对数据集中的离群点进行检测,而对局部离群点的检测性能较弱。基于此,本文通过引入快速搜索和发现密度峰值方法改进K-means聚类算法,提出了一种名为KLOD(local outlier detection based on improved K-means and least-squares methods)的局部离群点检测方法,以实现对局部离群点的精确检测。首先,利用快速搜索和发现密度峰值方法计算数据点的局部密度和相对距离,并将二者相乘得到γ值。其次,将γ值降序排序,利用肘部法则选择γ值最大的k个数据点作为K-means聚类算法的初始聚类中心。然后,通过K-means聚类算法将数据集聚类成k个簇,计算数据点在每个维度上的目标函数值并进行升序排列。接着,确定数据点的每个维度的离散程度并选择适当的拟合函数和拟合点,通过最小二乘法对升序排列的每个簇的每1维目标函数值进行函数拟合并求导,以获取变化率。最后,结合信息熵,将每个数据点的每个维度目标函数值乘以相应的变化率进行加权,得到最终的异常得分,并将异常值得分较高的top-n个数据点视为离群点。通过人工数据集和UCI数据集,对KLOD、LOF和KNN方法在准确度上进行仿真实验对比。结果表明KLOD方法相较于KNN和LOF方法具有更高的准确度。本文提出的KLOD方法能够有效改善K-means聚类算法的聚类效果,并且在局部离群点检测方面具有较好的精度和性能。 展开更多
关键词 离群点检测 K均值聚类 最小二乘法 密度峰值 目标函数值
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CONVERGENCE OF A CLASS OF MEANS OF H^p FUNCTIONS(0 被引量:1
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作者 Wang Jiwen Anhui University,China 《Analysis in Theory and Applications》 1993年第4期37-45,共9页
In this paper we study the convergence nf a class of means on H^p(G)(0<p<1),the means take the Bochner-Riesz means in[1],the generalized Bochner-Riesz means in[2],and the operators T^(Φ_r)in[3]as special cases.... In this paper we study the convergence nf a class of means on H^p(G)(0<p<1),the means take the Bochner-Riesz means in[1],the generalized Bochner-Riesz means in[2],and the operators T^(Φ_r)in[3]as special cases.We obtain weak-type estimates for the associated maximal operators and the maximal mean boundedness for the means. 展开更多
关键词 exp p<1)ON COMPACT LIE GROUPS CONVERGENCE OF A CLASS OF meanS OF H~p functionS
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On an Axiomatic about Functional Means
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作者 Mustapha Raissouli Mohamed Chergui Abdellah Alla 《Analysis in Theory and Applications》 CSCD 2018年第1期36-44,共9页
In this paper, we introduce an axiomatic approach about functional means. This includes that of operator means already introduced in the literature.
关键词 functional mean operator mean convex function.
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Application of Multiple Mean Generational Function Method to Typhoon Prediction over the Western North Pacific
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作者 Qing Chen Shuyun Yang +1 位作者 Yufang Liao Nengjin Chen 《Meteorological and Environmental Research》 CAS 2013年第4期26-28,共3页
[ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predicto... [ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predictors by mean generational function based on the rolling 50- year data of TYs frequency and sunspot number, and was repeated to generate forecasts year after year by optimal subset regression. [ Result] The results showed a reasonably high predictive ability dudng period 2000 -2010, with an average root mean square (RMSE) value of 1.92 and a mean absolute error (MAE) value of 1.64. [ Conclusion] Although the MMGF method needs further validation in the practical operation, it already has strong potential for the improvement of skill at forecasting annual frequency of TYs in the WNP. 展开更多
关键词 TYPHOONS Multiple mean generational function PREDICTION China
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Some Results on Areally Mean Valent Functions
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作者 魏寒柏 李万社 张良 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期1-15, ,共15页
Let M be the class of areally mean univalent function, f ∈M and In this paper, we estimate the arithmetical mean of coefficients Dn(λ) and the arithmetical mean of successive coefficients tn(λ) =||Dn+1(λ)|-|Dn(λ)... Let M be the class of areally mean univalent function, f ∈M and In this paper, we estimate the arithmetical mean of coefficients Dn(λ) and the arithmetical mean of successive coefficients tn(λ) =||Dn+1(λ)|-|Dn(λ)||. Our results are sharp. In addition, we also generalize Hayman's theorem on integral mean 展开更多
关键词 areally mean univalent functions maximal growth integral mean
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Generalized weighted functional proportional mean combining forecasting model and its method of parameter estimation
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作者 万玉成 盛昭潮 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第1期7-11,18,共6页
A new kind of combining forecasting model based on the generalized weighted functional proportional mean is proposed and the parameter estimation method of its weighting coefficients by means of the algorithm of quadr... A new kind of combining forecasting model based on the generalized weighted functional proportional mean is proposed and the parameter estimation method of its weighting coefficients by means of the algorithm of quadratic programming is given. This model has extensive representation. It is a new kind of aggregative method of group forecasting. By taking the suitable combining form of the forecasting models and seeking the optimal parameter, the optimal combining form can be obtained and the forecasting accuracy can be improved. The effectiveness of this model is demonstrated by an example. 展开更多
关键词 combining forecasting generalized weighted functional proportional mean parameter estimation quadratic programming
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APPROXIMATION BY FABER-LAURENT RATIONAL FUNCTIONS IN THE MEAN OF FUNCTIONS OF CLASS LP(T) WITH 1
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作者 A. Cavus D. M. Israfilov 《Analysis in Theory and Applications》 1995年第1期105-118,共14页
Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabc... Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabcrpolynomial F k,p (z),the kth p-Faber principle part F k.p (1/z) for Γ , and defined the nth p-Fcber- Laurent rational function Rn.p (f, z) and p- generalized modulus of continuity Ωp(f, t) of a function f of Lp(Γ) We inves-tigate some properties of Fk,p (z) and Fk.p (1/z). And then we prove a direct theorem characterizing the degree of approximation with respect to Ω (. , t) in the mean of functions of Lp(Γ) by the rational junctions Rn.p (. . z). 展开更多
关键词 APPROXIMATION BY FABER-LAURENT RATIONAL functionS IN THE mean OF functionS OF CLASS LP WITH 1 Rational
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APPROXIMATION OF CONTINUOUS FUNCTIONS BY GENERALIZED KARAMATA MEANS
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作者 S.A.SETTU 《Analysis in Theory and Applications》 1994年第1期88-98,共11页
A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obt... A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obtained. This sufficient condition is shown to be not enough for the order of approximation by partial sums of their Fourier series to be of Jackson order. The error estimate is shown to be the best possible. 展开更多
关键词 exp APPROXIMATION OF CONTINUOUS functionS BY GENERALIZED KARAMATA meanS
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Some Lacunary Sequence Spaces of Invariant Means Defined by Musielak-Orlicz Functions on 2-Norm Space
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作者 Mohammad Aiyub 《Applied Mathematics》 2014年第16期2602-2611,共10页
The purpose of this paper is to introduce and study some sequence spaces which are defined by combining the concepts of sequences of Musielak-Orlicz functions, invariant means and lacunary convergence on 2-norm space.... The purpose of this paper is to introduce and study some sequence spaces which are defined by combining the concepts of sequences of Musielak-Orlicz functions, invariant means and lacunary convergence on 2-norm space. We establish some inclusion relations between these spaces under some conditions. 展开更多
关键词 INVARIANT means Musielak-Orlicz functionS 2-Norm SPACE Lacunary SEQUENCE
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Pragmatic Functions of Discourse Marker I mean—a case study
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作者 王瑞 《海外英语》 2014年第22期256-258,共3页
The present study examines the pragmatic functions of the discourse marker I mean based on a case study of an American soap opera Desperate Housewives.Four pragmatic functions of I mean are detected and discussed.Amon... The present study examines the pragmatic functions of the discourse marker I mean based on a case study of an American soap opera Desperate Housewives.Four pragmatic functions of I mean are detected and discussed.Among them,two functions are more frequently used including supplementary and explanatory function,reminding and emphasizing function. 展开更多
关键词 PRAGMATIC function DISCOURSE MARKER I mean
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Wear State Recognition of Drills Based on K-means Cluster and Radial Basis Function Neural Network 被引量:2
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作者 Xu Yang 《International Journal of Automation and computing》 EI 2010年第3期271-276,共6页
Drill wear not only affects the surface smoothness of the hole, but also influences the life of the drill. Drill wear state recognition is important in the manufacturing process, which consists of two steps: first, d... Drill wear not only affects the surface smoothness of the hole, but also influences the life of the drill. Drill wear state recognition is important in the manufacturing process, which consists of two steps: first, decomposing cutting torque components from the original signals by wavelet packet decomposition (WPD); second, extracting wavelet coefficients of different wear states (i.e., slight, normal, or severe wear) with signal features adapting to Welch spectrum. Finally, monitoring and recognition of the feature vectors of cutting torque signal are performed by using the K-means cluster and radial basis function neural network (RBFNN). The experiments on different tool wears of the multivariable features reveal that the results of monitoring and recognition are significant and effective. 展开更多
关键词 Drill wear state recognition cutting torque signals wavelet packet decomposition (WPD) Welch spectrum energy K-means cluster radial basis function neural network
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GAUSS-MEAN VALUE FORMULA FOR TRIHARMONIC FUNCTIONS AND ITS APPLICATIONS IN CLIFFORD ANALYSIS
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作者 谷龙飞 张忠祥 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1419-1430,共12页
In this paper, the integral representation for some polyharmonic functions with values in a universal Clifford algebra Cl(Vn,n) is studied and Gauss-mean value formula for triharmonic functions with values in a Clif... In this paper, the integral representation for some polyharmonic functions with values in a universal Clifford algebra Cl(Vn,n) is studied and Gauss-mean value formula for triharmonic functions with values in a Clifford algebra Cl(Vn,n) are proved by using Stokes formula and higher order Cauchy-Pompeiu formula. As application some results about growth condition at infinity are obtained. 展开更多
关键词 triharmonic function Clifford algebra Gauss-mean value forrrmla
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Mean-square Almost Periodic Random Functions
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作者 江利娜 张传义 《Northeastern Mathematical Journal》 CSCD 2007年第3期215-225,共11页
In this paper, we present a basic theory of mean-square almost periodicity, apply the theory in random differential equation, and obtain mean-square almost periodic solution of some types stochastic differential equat... In this paper, we present a basic theory of mean-square almost periodicity, apply the theory in random differential equation, and obtain mean-square almost periodic solution of some types stochastic differential equation. 展开更多
关键词 mean-square convergence mean-square almost periodic random function Ito integration
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On the Equality of Weighted BajratarevićMeans to Quasi-Arithmetic Means
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作者 Yaxun Yang 《Journal of Applied Mathematics and Physics》 2024年第4期1126-1133,共8页
In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solv... In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solving an equivalent functional equation. We obtain the necessary and sufficient conditions for the equality equation. 展开更多
关键词 Bajraktarević means Quasi-Arithmetic means Equality Problem functional Equation
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基于正则判别与样条回归的红外光谱微量物证鉴定研究
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作者 王星 赵玉冰 +1 位作者 李杰 王元凤 《数理统计与管理》 北大核心 2025年第3期436-450,共15页
红外吸收光谱是法庭科学领域将犯罪现场中微量物证和非物证进行正确识别的重要技术。文章针对具有重复观测量小、高维、宽谱带且图像十分相近不易区分的红外光谱数据,提出了正则判别与函数型数据分析相结合的模型,该模型将用于有效波数... 红外吸收光谱是法庭科学领域将犯罪现场中微量物证和非物证进行正确识别的重要技术。文章针对具有重复观测量小、高维、宽谱带且图像十分相近不易区分的红外光谱数据,提出了正则判别与函数型数据分析相结合的模型,该模型将用于有效波数和波数带提取的双重分析目标。通过真实公开的基础材料含量有微小差异的油漆案例数据,开展了模型性能的实证研究,研究发现:(1)与常用的主成分分析降噪,广义线性套索路径法相比,正则判别有助于红外光谱标志性特征的提取,具有提取的特征准确度高和物证区分精度高的双稳健良好性能;(2)在提取标志性特征的基础上,进一步运用函数型数据分析中的同时置信带方法,通过样条回归估计协方差函数估计局部分段连续光谱波段。实验结果表明:正则判别与函数型数据分析的结合用于红外光谱稀疏标志特征的提取,精准鉴别不同物证和定量估计局部分段连续光谱段方面是行之有效的。 展开更多
关键词 独立正则判别 样条回归 质心收缩算法 红外吸收光谱 均值函数估计
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WOFOST伴随率定三温模型的玉米农田遥感蒸散发估算方法 被引量:1
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作者 冯克鹏 许德浩 庄淏然 《干旱区研究》 北大核心 2025年第1期166-178,共13页
通过遥感蒸散发模型估算实际蒸散发量的方法已被广泛使用,但精度提升仍是研究热点。作物生长模型在模拟作物蒸腾方面具有良好的机理性和精度。本文结合WOFOST作物生长模型和三温遥感蒸散发模型,提出了一种新的玉米农田遥感蒸散发估算方... 通过遥感蒸散发模型估算实际蒸散发量的方法已被广泛使用,但精度提升仍是研究热点。作物生长模型在模拟作物蒸腾方面具有良好的机理性和精度。本文结合WOFOST作物生长模型和三温遥感蒸散发模型,提出了一种新的玉米农田遥感蒸散发估算方法。核心思路是本地化WOFOST模型,在验证其模拟精度后,利用其模拟的作物蒸腾数据,构造伴随率定函数,率定三温模型的蒸腾组分,然后合并率定后的土壤蒸发组分,得到玉米农田实际蒸散发估算值。以涡度相关系统观测的实际蒸散发量为参照,评估了该方法的估算精度和适用性。结果表明,未经率定的三温模型蒸散发、作物蒸腾和土壤蒸发的相关系数分别为0.61、0.71、0.12,均方根误差为1.76 mm·d^(-1)、1.91 mm·d^(-1)、3.02 mm·d^(-1),纳什效率系数均为负。仅率定土壤蒸发后,相关系数提高至0.77,但误差仍然较大(1.91 mm·d^(-1)),纳什效率系数为-0.74。利用WOFOST模拟的作物蒸腾率定三温模型后,估算值与实际观测的相关系数显著提高至0.89,均方根误差降至0.65 mm·d^(-1),纳什效率系数达到0.79,表明该方法有效提高了三温遥感蒸散发模型的估算精度,并对其他遥感蒸散发模型的精度提升具有参考意义。 展开更多
关键词 时间序列谐波 伴随率定函数 k-means++聚类 作物生长模型 蒸散发
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一种基于核数据变换方法的遥感图像谱聚类算法
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作者 赵海军 陈华月 崔梦天 《林业工程学报》 北大核心 2025年第2期130-137,共8页
随着遥感图像在各行各业的日益广泛应用,遥感图像的处理变得愈来愈重要。为了实现谱聚类算法应用于林业工程中的遥感图像处理,本研究提出了一种基于核数据变换和角距离度量的谱聚类新算法。首先,通过对基于多变量核特征提取的一般核熵... 随着遥感图像在各行各业的日益广泛应用,遥感图像的处理变得愈来愈重要。为了实现谱聚类算法应用于林业工程中的遥感图像处理,本研究提出了一种基于核数据变换和角距离度量的谱聚类新算法。首先,通过对基于多变量核特征提取的一般核熵成分分析法的分析,并运用信息论概念和核密度估计密切相关的瑞利二次熵,提出了最佳特征提取和无监督降维方法,即最佳核熵成分分析法。它根据类或聚类信息方面的数据结构,采用一个额外的旋转,使得成分之间的独立性最大化;在这些成分中最佳地捕捉数据的高信息势部分,直接找到关于保留成分的数量的最大化信息势的基,以确保得到的解比标准的核熵成分分析得到的解保留更多(或相等)的信息势;并提出了采用梯度上升法来求解最佳核熵成分分析优化问题,具体实现是采用了一种简单的提前终止方案,以确保梯度达到一个额外迭代不会显著修改成本函数的区域。其次,通过对最佳核熵成分分析变换和样本外扩展的分析,构建了一种基于角距离度量的谱聚类算法,它采用角距离度量的核k-均值聚类目标,而不是采用基于欧氏距离的度量。优化过程采用最佳核熵成分分析空间中的角距离,以保证收敛到局部最优,从而实现图像的聚类。采用多光谱卫星图像的实验结果表明,本研究提出的谱聚类算法不仅适用于遥感图像的云筛选问题,而且相比目前其他先进的聚类算法有更好的分类性能。 展开更多
关键词 遥感图像 非线性特征提取 概率密度函数 K-均值 瑞利熵 谱聚类
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《现代汉语分类词典》与“汉语百宝箱”的编码系统及语义表达功能比较
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作者 苏新春 《天津师范大学学报(社会科学版)》 2025年第4期122-131,共10页
《现代汉语分类词典》(简称TMC)是由厦门大学苏新春主编、2013年由商务印书馆出版的词汇语义分类词典。①它拥有一个编码系统,用来给收入TMC中的8.3万个词分级分类,其编码系统称之为“义类码”。汉语百宝箱(简称BBX)是法国华裔学者夏诠... 《现代汉语分类词典》(简称TMC)是由厦门大学苏新春主编、2013年由商务印书馆出版的词汇语义分类词典。①它拥有一个编码系统,用来给收入TMC中的8.3万个词分级分类,其编码系统称之为“义类码”。汉语百宝箱(简称BBX)是法国华裔学者夏诠真先生主编的以汉语字词为主的语言知识库。②在与厦大团队合作后,BBX全面吸收了TMC的所有词语,包括义类码的编码系统。那么二者的编码系统有何异同?联结单位、使用过程、表义效果有何不同?特别是如何使二者相互兼容而不冲突,各司其职而相得益彰,这就很有必要对TMC与BBX各自语义分类系统的基本原则与方法作进一步的比较。二者的比较不仅有助于深入了解两个编码系统的编制原则与功能实现,在词汇理论上对准确把握词义关系、词义分类、词义系统的建构也有理论与实践的重要指导作用。 展开更多
关键词 《现代汉语分类词典》 “汉语百宝箱” 词义编码 语义功能
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从“食”到“品”:中国古代“茶”之饮用类词演变史考略
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作者 谢建娘 《泉州师范学院学报》 2025年第3期37-43,共7页
中国茶饮源远流长。自唐代茶文化勃兴,时人便以“食、饮、啜(歠)、餐(飡)、啖、吃(喫)、歃、尝、品”等词汇构筑饮茶行为指称体系。文章聚焦古代茶文学中的饮用类词汇,在语言学与文化学的双重观照下,对其进行系统描摹与探析。这些词汇... 中国茶饮源远流长。自唐代茶文化勃兴,时人便以“食、饮、啜(歠)、餐(飡)、啖、吃(喫)、歃、尝、品”等词汇构筑饮茶行为指称体系。文章聚焦古代茶文学中的饮用类词汇,在语言学与文化学的双重观照下,对其进行系统描摹与探析。这些词汇的历史嬗变,一方面是汉语词汇内在发展规律的体现,另一方面则与茶文化的演进轨迹深度交织——伴随着茶从食用、药用、饮用等社会功能,到精神、艺术等审美价值的不断拓展与升华,以致形成一个完整的茶文化体系。 展开更多
关键词 语义内涵 社会功用 审美价值
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