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A New Translation Theory of“Correspondency”and Its Difference from“Functional Equivalence”by Eugene A.Nida 被引量:1
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作者 何欣 《海外英语》 2015年第23期176-178,共3页
This paper puts forward a new translation theory of"correspondency", which is a more comprehensive and systematic translation theory that is especially effective in the translation criticism of"English-... This paper puts forward a new translation theory of"correspondency", which is a more comprehensive and systematic translation theory that is especially effective in the translation criticism of"English-Chinese"or"Chinese-English", absorbing some merits from Eugene A. Nida's"functional equivalence". A comparison of these two translation theories are offered in the paper, in hope of enlightening the readers in one aspect or another. 展开更多
关键词 "correspondency" TRANSLATION COMPARISON NIDA
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Topological phases and edge modes of an uneven ladder
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作者 商文创 韩熠宁 +1 位作者 Shimpei Endo 高超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期154-168,共15页
We investigate the topological properties of a two-chain quantum ladder with uneven legs,i.e.,the two chains differ in their periods by a factor of 2.Such an uneven ladder presents rich band structures classified by t... We investigate the topological properties of a two-chain quantum ladder with uneven legs,i.e.,the two chains differ in their periods by a factor of 2.Such an uneven ladder presents rich band structures classified by the closure of either direct or indirect bandgaps.It also provides opportunities to explore fundamental concepts concerning band topology and edge modes,including the difference of intracellular and intercellular Zak phases,and the role of the inversion symmetry(IS).We calculate the Zak phases of the two kinds and find excellent agreement with the dipole moment and extra charge accumulation.We also find that configurations with IS feature a pair of degenerate two-side edge modes emerging as the closure of the direct bandgap,while configurations without IS feature one-side edge modes emerging as not only the closure of both direct and indirect bandgaps but also within the band continuum.Furthermore,by projecting to the two sublattices,we find that the effective Bloch Hamiltonian corresponds to that of a generalized Su–Schrieffer–Heeger model or the Rice–Mele model whose hopping amplitudes depend on the quasimomentum.In this way,the topological phases can be efficiently extracted through winding numbers.We propose that uneven ladders can be realized by spin-dependent optical lattices and their rich topological characteristics can be examined by near future experiments. 展开更多
关键词 ladder model symmetry-protected topological phase topological invariant bulk-boundary correspondence
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On calculating glacial isostatic adjustment
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作者 L.M.Cathles 《Geodesy and Geodynamics》 EI CSCD 2024年第5期441-452,共12页
Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity profile.Here,we compare two methods for calculati... Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity profile.Here,we compare two methods for calculating the viscoelastic response to surface loading.In one,the elastic equation of motion is converted to a viscoelastic equation using the Correspondence Principle.In the other,elastic deformation is added to the viscous flow as isostatic adjustment proceeds.The two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA).The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic pre-stress.The methods agree if they use the same equations and boundary conditions.The origin of the differences is determined by varying the boundary conditions and pre-stress application. 展开更多
关键词 Glacial isostatic adjustment Viscoelastic normal modes Hydrostatic pre-stress Elastic buoyancy Correspondence principle
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Selective sampling with Gromov–Hausdorff metric:Efficient dense-shape correspondence via Confidence-based sample consensus
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作者 Dvir GINZBURG Dan RAVIV 《虚拟现实与智能硬件(中英文)》 EI 2024年第1期30-42,共13页
Background Functional mapping, despite its proven efficiency, suffers from a “chicken or egg” scenario, in that, poor spatial features lead to inadequate spectral alignment and vice versa during training, often resu... Background Functional mapping, despite its proven efficiency, suffers from a “chicken or egg” scenario, in that, poor spatial features lead to inadequate spectral alignment and vice versa during training, often resulting in slow convergence, high computational costs, and learning failures, particularly when small datasets are used. Methods A novel method is presented for dense-shape correspondence, whereby the spatial information transformed by neural networks is combined with the projections onto spectral maps to overcome the “chicken or egg” challenge by selectively sampling only points with high confidence in their alignment. These points then contribute to the alignment and spectral loss terms, boosting training, and accelerating convergence by a factor of five. To ensure full unsupervised learning, the Gromov–Hausdorff distance metric was used to select the points with the maximal alignment score displaying most confidence. Results The effectiveness of the proposed approach was demonstrated on several benchmark datasets, whereby results were reported as superior to those of spectral and spatial-based methods. Conclusions The proposed method provides a promising new approach to dense-shape correspondence, addressing the key challenges in the field and offering significant advantages over the current methods, including faster convergence, improved accuracy, and reduced computational costs. 展开更多
关键词 Dense-shape correspondence Spatial information Neural networks Spectral maps Selective sampling
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Evaluation of Soil Fertility Quality and Environmental Driving Factors in Different Soil Types of Artificial Forests
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作者 Songyu YU Zhenhui LIAO +3 位作者 Mingwu YANG Ronghui HU Yuanyuan SHI Junyu ZHAO 《Meteorological and Environmental Research》 2024年第2期64-70,共7页
The aim was to clarify the environmental driving factors of soil fertility indicators in artificial forests of Guangxi and comprehensively evaluate the soil fertility level.By collecting data on the current status of ... The aim was to clarify the environmental driving factors of soil fertility indicators in artificial forests of Guangxi and comprehensively evaluate the soil fertility level.By collecting data on the current status of soil in artificial forests,the spatial distribution of major soil fertility indicators was analyzed,and the distribution map of the fertility index of artificial forests in the entire region and the comprehensive fertility index of artificial forests of different soil types were obtained.Canonical correspondence analysis method was used to analyze soil fertility indicators and environmental factors,and the environmental driving factors of soil fertility indicators for artificial forests of the main soil types in Guangxi were obtained.The results showed that over 90%of the soil fertility index of artificial forests in the entire region was between 0.20 and 0.50.The order of soil fertility index of different soil types of artificial forests from high to low was yellow brown soil>yellow red soil>yellow soil>red soil>limestone soil>latosolic red soil>laterite.In artificial forests of latosolic red soil,the correlation between soil alkaline nitrogen and organic matter,annual average temperature was high,while the correlation between soil available phosphorus and organic matter,pH was high,and the correlation between soil available potassium and environmental factors such as slope,altitude,rainfall,accumulated temperature,and slope aspect was high.In artificial forests of red soil,the correlation between soil alkaline nitrogen and slope,altitude was high,while the correlation between soil available phosphorus and accumulated temperature,rainfall was high,and the correlation between soil available potassium and pH was high.In artificial forests of limestone soil,there was a high correlation between soil alkaline nitrogen and slope,organic matter,a high correlation between soil available phosphorus and accumulated temperature,rainfall,and a high correlation between soil available potassium and pH. 展开更多
关键词 Soil fertility index GIS Forest soil Canonical correspondence analysis
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The Deconvolution Method for Obtaining Correspondence in Data-Independent Acquisition Mass Spectrometry Data
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作者 Mingming Lyu Xinye Bian Changjiu He 《Journal of Computer and Communications》 2024年第2期11-25,共15页
Although data-independent acquisition (DIA) shows powerful potential in achieving comprehensive peptide information acquisition, the difficulty in determining the precursor m/z and distinguishing fragment ions has pos... Although data-independent acquisition (DIA) shows powerful potential in achieving comprehensive peptide information acquisition, the difficulty in determining the precursor m/z and distinguishing fragment ions has posed challenges in DIA data analysis. To address this challenge, a common approach is to recover the correspondence between precursor ions and fragment ions, followed by peptide identification using traditional data-dependent acquisition (DDA) database searching. In this study, we propose a cosine similarity-based deconvolution method that rapidly establishes the correspondence between chromatographic profiles of precursor ions and fragment ions through matrix calculations. Experimental results demonstrate that our method, referred to as CosDIA, yields a peptide identification count close to that of DIA-umpire. However, compared to DIA-umpire, we can establish the correspondence between original MS/MS spectra and pseudo-MS/MS spectra. Furthermore, compared to the CorrDIA method, our approach achieves higher efficiency in terms of time, reducing the time cost of the analysis process. These results highlight the potential advantages of the CosDIA method in DIA data analysis, providing a powerful tool and method for large-scale proteomics research. 展开更多
关键词 MS/MS Spectra XICs CORRESPONDENCE Matrix Isotopic Peak Cluster
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Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 Special Relativity’s Hyperbolic Versus Circular Versions Galilean Kinematics Partial Equivalence of SR and Newton’s Theories Algebra of Relativistic and the Corresponding Galilean Velocities
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The Factors Shaping Synonymous Codon Usage in the Genome of Burkholderia mallei 被引量:4
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作者 赵胜 张琴 +2 位作者 陈智华 赵益新 钟金城 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期362-372,共11页
Burkholderia mallei is regarded as a potential biological weapon by the Centers for Disease Control and Prevention. In this study, the main factors shaping codon usage in the genome of B. mallei ATCC 23344 were firstl... Burkholderia mallei is regarded as a potential biological weapon by the Centers for Disease Control and Prevention. In this study, the main factors shaping codon usage in the genome of B. mallei ATCC 23344 were firstly reported. The results showed that the primary trend in codon usage variation in the B. mallei is due to translational selection; while compositional mutation bias is relatively the weaker influence and the hydrophobicity of each protein and gene length are only the minor influences. At the same time, 21 codons defined firstly as 'optimal codons' might provide more useful information for the expression of target genes and development of a vaccine to prevent glanders. 展开更多
关键词 Burkholderia mallei ATCC 23344 codon usage correspondence analysis
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Spatial and environmental effects on plant communities in the Yellow River Delta, Eastern China 被引量:8
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作者 宋创业 刘高焕 刘庆生 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期117-122,I0002,共7页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distributi... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods. Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis. The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium. Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation. Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively. Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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OSEK/VDX OS服务调用的规范一致性检测方法 被引量:5
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作者 李银国 叶家盛 蒋建春 《重庆邮电大学学报(自然科学版)》 北大核心 2010年第6期786-790,共5页
OSEK/VDX(open systems and the corresponding interfaces for automobile electronic/vehicle distributed execu-tive)OS规范描述了一个嵌入式实时操作系统,对系统服务调用的上下文做了严格的限制。违反系统服务调用规范是一种很隐... OSEK/VDX(open systems and the corresponding interfaces for automobile electronic/vehicle distributed execu-tive)OS规范描述了一个嵌入式实时操作系统,对系统服务调用的上下文做了严格的限制。违反系统服务调用规范是一种很隐蔽的错误,不会被编译器发现。提出一种OSEK/VDX OS系统服务调用规范一致性的检测方法,利用森林图描述用户自定义代码中的函数及其调用关系,采用矩阵描述OSEK/VDX OS系统服务调用的规则,遍历该森林图的函数调用路径,对于每条路径,结合该规则矩阵判断其规范一致性。实验和分析表明该方法能有效地检测用户自定义代码中隐藏的违反OSEK/VDX OS系统服务调用规范的错误。 展开更多
关键词 嵌入式实时操作系统 OSEK/VDX(open systems and the CORRESPONDING interfaces for AUTOMOBILE electronic/vehicle distributed executive)OS规范 系统服务调用 一致性检测
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Distribution Patterns of Ground Moss Species and Its Relationships with Environmental Factors in Changbai Mountain, Northeast China 被引量:5
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作者 郭水良 曹同 《Acta Botanica Sinica》 CSCD 2001年第6期631-643,共13页
The relationships of 42 species of ground moss with six environmental factors in 41 sites on Changbai Mountain Biosphere Reserve were analyzed. Four site groups and four groups of ground moss ecological species were i... The relationships of 42 species of ground moss with six environmental factors in 41 sites on Changbai Mountain Biosphere Reserve were analyzed. Four site groups and four groups of ground moss ecological species were identified using the method of Two-way Indicator Species Analysis (TWINSPAN). The results of Detrended Canonical. Correspondence Analysis (DCCA) showed that altitude, soil sand content, soil acidity, forest canopy coverage and soil water content are the five major environmental factors influencing the distributional patterns of the moss species. The four groups of ecological species, which correspond well with the four site groups, are projected on the species-environment biplot of DCCA. Group 1 dominated in the bogs of Larix olgensis forest, group 2 in the alpine tundra, group 3 in the dense conifer forest, and group 4 mainly in the Betula ermanii community and the Betula ermanii-Larix olgensis forest in sub-alpine respectively. 展开更多
关键词 MOSSES Changbai Mountain distribution pattern detrended canonical correspondence analysis
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Non-iterative image feature matching algorithm based on reference point correspondences 被引量:1
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作者 张维中 张丽艳 +2 位作者 王小平 丁志安 周玲 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期190-195,共6页
Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded ta... Based on the coded and non-coded targets, the targets are extracted from the images according to their size, shape and intensity etc., and thus an improved method to identify the unique identity(D) of every coded target is put forward and the non-coded and coded targets are classified. Moreover, the gray scale centroid algorithm is applied to obtain the subpixel location of both uncoded and coded targets. The initial matching of the uncoded target correspondences between an image pair is established according to similarity and compatibility, which are based on the ID correspondences of the coded targets. The outliers in the initial matching of the uncoded target are eliminated according to three rules to finally obtain the uncoded target correspondences. Practical examples show that the algorithm is rapid, robust and is of high precision and matching ratio. 展开更多
关键词 reference points detection coded and non-coded target SUBPIXEL gray scale centroid point correspondence
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Analysis on Chemical Compositions in Chinese Wolfberry from Different Producing Areas 被引量:4
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作者 董海峰 任永丽 《Agricultural Science & Technology》 CAS 2012年第9期1870-1872,共3页
[Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfber... [Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfberry samples, the composition of trace elements and the sample sources. [Method] The determined contents of trace elements and ratios of zinc to copper (Zn/Cu) of wolfberry from 11 different producing areas of Qinghai and Ningxia regions were adopted to construct the raw measurement data matrix, to analyze the distribution characteristics of the trace ele- ments in wolfberry from Qinghai and Ningxia by using the corresponding cluster analysis method. [Result] The quality of wolfberry samples in 7hongning County, Zhongwei City, Pingluo County, Shizuishan City, Heicheng Town of Ningxia Hui Au-tonomous Region and Hehuang Valley, Golmud City of Qinghai Province is mainly related to the contents of Zn and Mn; Zn/Cu greatly affects the quality of Chinese wolfberry in Dulan County of Qinghai Province; Fe has great effect on the quality of Chinese wolfberry in Yinchuan City of Ningxia Hui Autonomous Region; Cu greatly affects the quality of Chinese wolfberry in Nuomuhong Village of Qinghai Province and a wolfberry research institute in Ningxia. [Conclusion] The relationship between the quality of wolfberry from different producing areas and the trace elements was investigated, which provides theoretical and practical basis for the cultivation, har- vesting, processing, and further development and utilization of Chinese wolfberry resources from different producing areas. 展开更多
关键词 Chinese wolfberry Correspondence cluster analysis Trace elements
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DENSE DISPARITY MAP ESTIMATION USING GENETIC ALGORITHMS 被引量:1
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作者 王彪 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期184-191,共8页
An approach to addressing the stereo correspondence problem is presented using genetic algorithms (GAs) to obtain a dense disparity map. Different from previous methods, this approach casts the stereo matching as a mu... An approach to addressing the stereo correspondence problem is presented using genetic algorithms (GAs) to obtain a dense disparity map. Different from previous methods, this approach casts the stereo matching as a multi-extrema optimization problem such that finding the fittest solution from a set of potential disparity maps. Among a wide variety of optimization techniques, GAs are proven to be potentially effective methods for the global optimization problems with large search space. With this idea, each disparity map is viewed as an individual and the disparity values are encoded as chromosomes, so each individual has lots of chromosomes in the approach. Then, several matching constraints are formulated into an objective function, and GAs are used to search the global optimal solution for the problem. Furthermore, the coarse-to-fine strategy has been embedded in the approach so as to reduce the matching ambiguity and the time consumption. Finally, experimental results on synthetic and real images show the performance of the work. 展开更多
关键词 stereo correspondence disparity map genetic algorithms coarse-to-fine strategy
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Status of and Strategies for Ecotourism Development in Chaozhou City 被引量:1
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作者 陈蔚辉 林杨波 《Journal of Landscape Research》 2010年第9期96-99,共4页
Ecotourism development can not only bring economic,ecological and environmental benefits,but also help realize the sustainable development of tourism industry. The authors analyzed the current ecotourism development o... Ecotourism development can not only bring economic,ecological and environmental benefits,but also help realize the sustainable development of tourism industry. The authors analyzed the current ecotourism development of Chaozhou City and existing problems,tried to propose corresponding strategies for its healthy development from legislative and scientific perspectives. 展开更多
关键词 Chaozhou ECOTOURISM STATUS quo CORRESPONDING STRATEGIES
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Application of Lexical Approach to Teaching of Business English Correspondence 被引量:1
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作者 江韵 《海外英语》 2015年第20期26-28,33,共4页
Because of poor vocabulary, improper use of lexis, and interference of first language, it is difficult for students in voca-tional school to learn Business English Correspondence well. Business English has close relat... Because of poor vocabulary, improper use of lexis, and interference of first language, it is difficult for students in voca-tional school to learn Business English Correspondence well. Business English has close relations with lexical chunks, whichmakes it necessary to apply lexical approach to teaching of Business English Correspondence. This paper intends to explore its the-oretical foundations and emphasize how to apply lexical approach to teaching of Business English Correspondence in vocationalschool. 展开更多
关键词 LEXICAL APPROACH BUSINESS ENGLISH CORRESPONDENCE TEACHING
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Pragmatic Vagueness in Business Correspondences——A Perspective of PP
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作者 洪小丽 《海外英语》 2015年第19期209-211,共3页
Pragmatic vagueness is frequently used in business correspondences and it offers benefits to the addressers by making business letter more flexible,appropriate and polite.This paper focuses on the employment of vague ... Pragmatic vagueness is frequently used in business correspondences and it offers benefits to the addressers by making business letter more flexible,appropriate and polite.This paper focuses on the employment of vague language in international business correspondences based on the Politeness Principle.In this study,the pragmatic effect of vague language in business correspondence is illustrated and summarized as a motivated factor to better show politeness and respect.The use of vague language motivated by politeness consequently leads to a more smooth,successful and desired communication in business world. 展开更多
关键词 PRAGMATIC VAGUENESS BUSINESS CORRESPONDENCE POLITENESS PRINCIPLE functions
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Analysis of Vague Language in Enquiry and Offers——from English business correspondence
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作者 吴恩梅 《疯狂英语(理论版)》 2017年第4期191-192,共2页
English business correspondence plays an important role in business activities. People take it for granted that it should be cautious and accurate,but neglect the necessity and importance of vague language. Therefore,... English business correspondence plays an important role in business activities. People take it for granted that it should be cautious and accurate,but neglect the necessity and importance of vague language. Therefore, it is very important to apply vague language to English business correspondence. 展开更多
关键词 vague language English business correspondence ENQUIRY OFFER
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Correct Expression of Post-positive Attributives in Foreign Trade English Correspondence
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作者 朱莉蓉 《海外英语》 2019年第22期113-114,123,共3页
The Foreign Trade English Correspondence is one of the main courses of International Trade majors.Due to the habit of thinking in Chinese,students usually cannot correctly and flexibly use post-positive attributives i... The Foreign Trade English Correspondence is one of the main courses of International Trade majors.Due to the habit of thinking in Chinese,students usually cannot correctly and flexibly use post-positive attributives in the correspondence writing of foreign trade.Participle phrases,prepositional phrases,attributive clauses,infinitive phrases,adjective phrases and apposition clauses all can follow nouns as post-positive attributives to modify nouns.Mastering the correct expression of post-positive attrib⁃utives will help students improve their writing competence of foreign trade correspondence. 展开更多
关键词 Foreign Trade English Correspondence Correct Expression
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Seasonal variation of Microcystis in Lake Taihu and its relationships with environmental factors 被引量:16
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作者 TAN Xiao KONG Fanxiang +3 位作者 ZENG Qingfei CAO Huansheng QIAN Shanqin ZHANG Min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期892-899,共8页
In order to monitor the changes of Microcystis along with temporal and spatial variations, seasonal variation of Microcystis in Lake Taihu was investigated by 16S-23S rRNA internal transcribed spacer denaturing gradie... In order to monitor the changes of Microcystis along with temporal and spatial variations, seasonal variation of Microcystis in Lake Taihu was investigated by 16S-23S rRNA internal transcribed spacer denaturing gradient gel electrophoresis (16S-23S rRNA-ITS DGGE) and microscopic evaluation. Samples were collected quarterly at four sites (River Mouth, Meiliang Bay, Cross Area, and Lake Center) from August 2006 to April 2007. Results showed that Microcystis dominated total phytoplankton abundance at the four sites in all seasons except winter. The average annual abundance of Microcystis was relatively high at River Mouth and Meiliang Bay, reaching 81.22×10^6 and 61.32×10^6 cells/L, respectively. For temporal variations, Shannon-Wiener diversity index (H') according to DGGE profile revealed the richness of Microcystis in summer (H' = 1.375±0.034) and winter (H' = 1.650 ±0.032) was lower than that in spring (H' = 2.078 ±0.031) and autumn (H' = 2.365 ±0.032) (P 〈 0.05). While for spatial variations, the richness of Microcystis at River Mouth (H' = 2.015± 0.074) was higher than at other sites during four seasons (P 〈 0.01). Very few differences of Microcystis diversity in the same season were observed among the other three sites (P 〉 0.05). Canonical correspondence analysis (CCA) was performed to elucidate the relationships between Microcystis operational taxonomic units (OTUs) composition and the environmental factors. Results of CCA revealed that temperature was strongly positively correlated with the first axis (r = 0.963), while TSS was negative correlated with the second axis (r = -0.716). Phylogenetic tree based on the sequencing results of target bands on DGGE gel indicated that samples collected in summer and winter constituted two separated clusters. 展开更多
关键词 Lake Taihu BLOOMS MICROCYSTIS rRNA-ITS DGGE canonical correspondence analysis
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