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Trial application of the envelope method to the potential ambiguity problem
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作者 Li-Yuan Hu Yu-Shou Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期73-80,共8页
The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and f... The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering components.By contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,respectively.Hence,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity problem.In this study,we conducted a trial application of the envelope method to the potential ambiguity problem.The envelope method was improved by including uncertainties in the experimental data.The colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the analyses.For each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is refractive.The calculated angular distributions were decomposed into nearside and farside scattering components.Using the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside components.The capability of the envelope method to analyze the potential ambiguities was also discussed. 展开更多
关键词 Elastic scattering Optical potential ambiguities Envelope method Nearside/farside decomposition
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Multi-layer phenomena in petawatt laser-driven acceleration of heavy ions
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作者 苏琬晴 曹喜光 +2 位作者 马春旺 王玉廷 张国强 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期70-76,共7页
Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW l... Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, Ta, Au, Pb, Th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. The layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum,ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. Two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process. 展开更多
关键词 petawatt laser-plasma interaction laser-driven heavy-ion accelerator for synthesizing superheavy nuclei PARTICLE-IN-CELL multi-layer phenomena target fabrication
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Translation Strategies of Ambiguity in English Language and Literature
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作者 Ying Gao 《Journal of Contemporary Educational Research》 2024年第2期138-143,共6页
The translation of English language and literary works has always been crucial for cross-cultural communication.However,a key challenge in translating such works is the accurate communication of ambiguity,which refers... The translation of English language and literary works has always been crucial for cross-cultural communication.However,a key challenge in translating such works is the accurate communication of ambiguity,which refers to expressions deliberately used in English texts with unclear meanings.These expressions are often poetic and carry deep symbols and implications,adding a unique charm to literary works.This article explores the manifestations of ambiguity in English language and literature and the translation strategies that can be employed to optimize the translation of ambiguity in the English language and literature. 展开更多
关键词 ENGLISH Language and literature ambiguity TRANSLATION
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REGULARIZATION APPROACH FOR FAST INTEGER AMBIGUITY RESOLUTION OF MEDIUM-LONG BASELINE GPS NETWORK RTK 被引量:4
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作者 罗孝文 欧吉坤 袁运斌 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期235-242,共8页
An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be imp... An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be improved by the regularized matrix. The relative floating ambiguity can be computed only by using the data of several epochs. Combined with the LAMBDA method, the new approach can correctly and quickly fix the integer ambiguity and the success rate is 100% in experiments. Through using measured data sets from four mediumlong baselines, the new method can obtain exact ambiguities only by the Ll-frequency data of three epochs. Compared with the existing methods, the improved method can solve the ambiguities of the medium-long baseline GPS network RTK only using L1-frequency GPS data. 展开更多
关键词 GPS network RTK integer ambiguity fast resolution
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Correlation between Chinese learners' tolerance of ambiguity and their English achievement
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作者 李素真 《Sino-US English Teaching》 2008年第3期35-38,共4页
Tolerance of ambiguity, an important emotional factor, imposes vital influence on second language acquisition. In this study, questionnaires are adopted to investigate the correlation between non-English major's tole... Tolerance of ambiguity, an important emotional factor, imposes vital influence on second language acquisition. In this study, questionnaires are adopted to investigate the correlation between non-English major's tolerance of ambiguity and their English achievement. The result shows that students with different degrees of tolerance of ambiguity can be significantly different in their language performance. Based on the analysis, this article proposes some effective measures to improve the degree of tolerance of ambiguity in English teaching. 展开更多
关键词 tolerance of ambiguity English achievement CORRELATION
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Charlotte Bronte's writing career: The consistent ambiguity of gender
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作者 杨红霞 《Sino-US English Teaching》 2009年第12期60-63,共4页
Although many Chinese scholars have concentrated on Jane Eyre, yet few of them have made research on the other works of Charlotte Bronte. This paper will analyze Jane Eyre, Shirley and Villette in terms of ambiguity o... Although many Chinese scholars have concentrated on Jane Eyre, yet few of them have made research on the other works of Charlotte Bronte. This paper will analyze Jane Eyre, Shirley and Villette in terms of ambiguity of gender, in order to disclose the writing career of Charlotte and the influence that she has placed on the latter women writers. 展开更多
关键词 CHARLOTTE Jane Eyre Shirley VILLETTE ambiguity of gender
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Types of Ambiguity in English: their Recognition and Removal 被引量:1
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作者 许素波 《衡水师专学报》 1999年第2期14-19,共6页
This essay is intended to present a detailed analysis of the three types of ambiguity in English, i.e. phonetic, lexical and structural ambiguities which exert great influence on the understanding in communications. T... This essay is intended to present a detailed analysis of the three types of ambiguity in English, i.e. phonetic, lexical and structural ambiguities which exert great influence on the understanding in communications. The recognition and removal of them, therefore, is of great necessity for both learners and users of the languages and a full awareness of the context, in which the language is used and which is responsible for the arising of most ambiguities, might well serve as an effective solution to the understanding problem. 展开更多
关键词 英语 歧义 言语交际 语言理解 语境
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Oral Fossilization Phenomena of Vocational College Non-English Majors
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作者 谢盈盈 《海外英语》 2011年第14期389-390,共2页
This thesis sets out to classify the fossilized errors made by the subjects from lexical and syntactic levels respectively,through the empirical experiment and questionnaire.
关键词 FOSSILIZATION phenomena Experiment LEXICAL SYNTACTIC
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A Brief Analysis of Ambiguity of Words' Meaning in Translation
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作者 杨柳 《海外英语》 2016年第7期140-141,共2页
As you can see from the title,we try to provide a brief analysis of ambiguity of words' meaning in translation practice,namely,what is ambiguity of a meaning of a word and how it is caused,and how it affects trans... As you can see from the title,we try to provide a brief analysis of ambiguity of words' meaning in translation practice,namely,what is ambiguity of a meaning of a word and how it is caused,and how it affects translation.What effective methods are available to help us achieve a successful translation? Although a perfect solution for the problems presented by the ambiguity of words' meaning is difficult to find,we try to do what it can to contribute to the solution and draw people's attention to those problems. 展开更多
关键词 ambiguity MEANING of WORDS TRANSLATION
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Review of Tolerance of Ambiguity
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作者 王爽爽 《海外英语》 2015年第18期224-225,230,共3页
In this paper,definitions of tolerance of ambiguity both at home and abroad are reviewed first.Then studies of tolerance of ambiguity and foreign language teaching both home and abroad are introduced.At last,the paper... In this paper,definitions of tolerance of ambiguity both at home and abroad are reviewed first.Then studies of tolerance of ambiguity and foreign language teaching both home and abroad are introduced.At last,the paper proposed that it is of great significance and practicality for us to make further studies on tolerance of ambiguity. 展开更多
关键词 TOLERANCE of ambiguity FOREIGN LANGUAGE TEACHING
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Analysis of Ambiguity in Newspaper Headlines from a Cognitive Perspective
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作者 刘启迪 《海外英语》 2011年第15期310-312,共3页
Ambiguity in newspaper headlines have been studied by many people, which mostly focuses upon the traditional linguistics perspective: lexical, grammatical and syntactical. In this paper, the author intends to study th... Ambiguity in newspaper headlines have been studied by many people, which mostly focuses upon the traditional linguistics perspective: lexical, grammatical and syntactical. In this paper, the author intends to study the ambiguity in newspaper headlines from the cognitive perspective in order to find how people perceive the ambiguous headlines. To support the analysis, many examples of ambiguous headlines are collected to investigate into way people perceive them. Finally, the author concluded that in the cognitive perspective, people are prone to accept one of the two or more interpretations about the ambiguous headlines according to the following factors: their back ground knowledge, the common sense, the social-cultural environment as well as their personal altitudes, which are drawn upon from the image schema theory. 展开更多
关键词 ambiguity NEWSPAPER HEADLINE COGNITIVE PERSPECTIVE
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An Analysis of the Syntactic Ambiguity in English Writing in College of Arts
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作者 李萍 《教育教学论坛》 2010年第6期89-89,15,共2页
Writing correct sentence conforming to local English expression is the foundation of English writing. Therefore,in order to help to improve artistic college students' level of English writing,this thesis will try ... Writing correct sentence conforming to local English expression is the foundation of English writing. Therefore,in order to help to improve artistic college students' level of English writing,this thesis will try to analyze several syntactic ambiguity phenomena by means of citing typical compositions written by my students who come from different departments of the college of arts. 展开更多
关键词 英语 高校 语法 教材
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Lattice Boltzmann modeling of transport phenomena in fuel cells and flow batteries 被引量:12
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作者 Ao Xu Wei Shyy Tianshou Zhao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第3期555-574,共20页
Fuel cells and flow batteries are promising technologies to address climate change and air pollution problems. An understanding of the complex multiscale and multiphysics transport phenomena occurring in these electro... Fuel cells and flow batteries are promising technologies to address climate change and air pollution problems. An understanding of the complex multiscale and multiphysics transport phenomena occurring in these electrochemical systems requires powerful numerical tools. Over the past decades, the lattice Boltzmann (LB) method has attracted broad interest in the computational fluid dynamics and the numerical heat transfer communities, primarily due to its kinetic nature making it appropriate for modeling complex multiphase transport phenomena. More importantly, the LB method fits well with parallel computing due to its locality feature, which is required for large-scale engineering applications. In this article, we review the LB method for gas-liquid two-phase flows, coupled fluid flow and mass transport in porous media, and particulate flows. Examples of applications are provided in fuel cells and flow batteries. Further developments of the LB method are also outlined. 展开更多
关键词 Lattice Boltzmann method Transport phenomena Multiphase flow Fuel cells Flow batteries
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Analysis of the ambiguity of log-constrained seismic impedance inversion 被引量:6
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作者 Li Guofa Li Hao +1 位作者 Ma Yanyan Xiong Jinliang 《Petroleum Science》 SCIE CAS CSCD 2011年第2期151-156,共6页
Although the ambiguity of seismic inversion is widely recognized in both theory and practice, so far as a concrete inversion example is concerned, there is not any objective, controllable method or any standard for ho... Although the ambiguity of seismic inversion is widely recognized in both theory and practice, so far as a concrete inversion example is concerned, there is not any objective, controllable method or any standard for how to evaluate and determine its ambiguity and reliability, especially for the high frequency components beyond the effective seismic frequency band. Taking log-constrained impedance inversion as an example, a new appraisal method is proposed on the basis of analyzing a simple geological model. Firstly, the inverted impedance model is transformed to a reflection coefficient series. Secondly, the maximum effective frequency of the real seismic data is chosen as a cutoff point and the reflection coefficient series is decomposed into two components by low-pass and high-pass filters. Thirdly, the geometrical reflection characteristics of the high-frequency components and that of the real seismic data are compared and analyzed. Then, the reliability of the inverted impedance model is appraised according to the similarity of geometrical characteristics between the high-frequency components and the real seismic data. The new method avoids some subjectivity in appraising the inverted result, and helps to enhance the reliability of reservoir prediction by impedance inversion technology. 展开更多
关键词 Log-constrained IMPEDANCE reflection coefficients seismic inversion ambiguity
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《Seven Types of Ambiguity》之“ambiguity”的译名研究 被引量:1
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作者 肖瑜 《湖南广播电视大学学报》 2013年第3期18-22,共5页
燕卜荪《Seven Types of Ambiguity》中"ambiguity"作为燕卜荪诗学的核心术语而广为人知,并对其后的新批评文论产生了极大影响。这个术语在中国的译名以"多义"为起始,又经历了"晦涩""、朦胧"&q... 燕卜荪《Seven Types of Ambiguity》中"ambiguity"作为燕卜荪诗学的核心术语而广为人知,并对其后的新批评文论产生了极大影响。这个术语在中国的译名以"多义"为起始,又经历了"晦涩""、朦胧""、含混""、复义"等多种译名的变迁,体现了国内学界对于新批评乃至整个西方文论的接受现状。本文通过对其译名变迁过程的梳理以及对各种译名的辨析,最终认为"复义"是目前对于"ambiguity"较为适合的译名,并希望以此为突破点,加强国内学界对于相关文论术语定义范畴的共同认知。 展开更多
关键词 燕卜荪 ambiguity 复义 含混 新批评
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Improvement of GPS ambiguity resolution using prior height information. Part Ⅰ: The method by using height validation 被引量:5
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作者 朱建军 Rock Santerre 《Journal of Central South University of Technology》 2002年第3期186-190,共5页
It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height inf... It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height information in bathymetric surveying by GPS positioning and how to use the prior height information and to obtain a robust result. The authors deal with the collection and the description of the prior height and the method using height validation to improve the ambiguity resolution. The principle of the method, the relationships between the height threshold and the ambiguity search space are presented. A method to determine the threshold for the height validation is suggested. The field tests are carried out to show the feasibility of the proposed methods. 展开更多
关键词 ambiguity resolution HEIGHT VALIDATION ROBUSTNESS OTF techniques
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A NOVEL ALGORITHM FOR SIDE PEAKS SUPPRESSION OF AMBIGUITY FUNCTION FOR PASSIVE RADAR BASED ON CHINESE DTTB SIGNAL 被引量:5
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作者 Li Jichuan Lu Xiaode Zhao Yaodong 《Journal of Electronics(China)》 2012年第6期485-492,共8页
The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relati... The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relative positions and the reasons for the side peaks are analyzed and a new algorithm for side peaks suppression is proposed in this paper. The algorithm, in consideration of the characteristics of the structure of the frame, can eliminate the side peaks completely in the valid Doppler observation interval by setting the reference signals to zero at equal intervals. Both the simulative and experimental results show that this algorithm can improve the performance of target detection of the passive radar based on DTTB signal. 展开更多
关键词 Passive radar Digital Television Terrestrial Broadcasting (DTTB) ambiguity Function (AF) Side peaks suppression
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Numerical simulation of flow phenomena and optimum operation of tundish 被引量:2
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作者 时章明 鄂加强 +3 位作者 刘春洋 梅炽 张全 周应其 《Journal of Central South University of Technology》 2003年第2期155-158,共4页
To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liq... To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liquid steel in tundish were studied. The results show that the configuration and operation of tundish play an important part in quality assurance of grade 20 carbon-steel products. By optimizing the configuration of the tundish, the depth of liquid bath in tundish is enhanced, the impact of liquid steel is decreased, and the residence time of liquid steel is lengthened, which is useful for eliminating inclusions and blowholes and improving the service life of tundish. Improving the pouring and tapping operation of liquid steel can avoid the contact of liquid steel with air, and decrease re-oxidation. Strict control of the superheat degree of casting liquid steel can decrease the non-metallic inclusion content of the re-oxidation in billets and reduce the erosion of tundish. The inclusions and blowholes in the continuous casting grade 20 steel billets are reduced to a great extent and qualification rate is enhanced from 60% to 80%. 展开更多
关键词 TUNDISH flow phenomena NUMERICAL simulation OPTIMUM
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INVESTIGATION OF PHYSICO METALLURGICAL PHENOMENA FOR THE CC FORMING OF WCP/Fe C COMPOSITES 被引量:1
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作者 B.Z. Li1) ,Y.P. Song1) ,K.U. Kainer2) , H. Zhang3) , J.P.Xie1) and R.Xiang4) 1) Department of Materials Engineering ,Luoyang Institute of Technology ,Luoyang 471039 ,China2) Institute of Material Science and Technology ,TU Clausthal,D 38678 Clausthal 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第4期566-572,共7页
Theinvestigation of physicometallurgicalphenomena forthe CC formingof WCP/ Fe Ccom posites wasperformed. Resultsshow that underthe patentcondition, WCP/ Fe Ccomposite surfacelayerof16 20 m m heavycross sectio... Theinvestigation of physicometallurgicalphenomena forthe CC formingof WCP/ Fe Ccom posites wasperformed. Resultsshow that underthe patentcondition, WCP/ Fe Ccomposite surfacelayerof16 20 m m heavycross sectioncan beacquiredintheoutsideofa hollow cylin der. The surface of CTC particlescould be partially dissolved by Fe containing melt. Thefineshortstick like WCcrystallitesarein situseparated neartothesurfaceof CTC particles.Far from the CTC particles,someseparated, finetungsten carbidecrystallitesand Fe, W,Mo and Cretc. containing web composite carbides, are distributed on the matrix of WCP/ Fe Ccomposite. Fe Calloy matrix of the hollow composite cylinder is alloyed in differenthigh levels. 展开更多
关键词 physicometallurgical phenomena CC forming WCP/ Fe Ccomposites of heavycross section
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RANGE AMBIGUITY DISTRIBUTION CHARACTERISTIC OF SPACEBORNE SAR AND ITS DESIGN CONSIDERATION 被引量:1
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作者 荆麟角 《Journal of Electronics(China)》 1995年第2期160-167,共8页
A new approach is proposed which can satisfy the range ambiguity requirement while keep the antenna width not to be enlarged and get the high quality image also. Here the chirp slope of the transmitted linear frequenc... A new approach is proposed which can satisfy the range ambiguity requirement while keep the antenna width not to be enlarged and get the high quality image also. Here the chirp slope of the transmitted linear frequency modulated pulses is reversed alternately. Therefore, during the range compression significant portion of the ambiguous return which is due to the mismatching with the signal reference function is suppressed. The suggested method provides significant improvement in range ambiguity ratio and can be utilized in attaining wider swath. 展开更多
关键词 SAR Range ambiguity ratio(RAR) INCIDENCE angle PRF Uniform distribution COSINE weighting CHIRP
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