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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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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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An Unambiguity and Anti-Range Eclipse Method for PD Radar Using Biphase Coded Signals
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作者 Jihong Yan Weihan Ni +1 位作者 Jianshu Zhai Haiyang Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1337-1351,共15页
Target detection is an important research content in the radar field.At present,efforts are being made to optimize the precision of detection information.In this paper,we use the high pulse repetition frequency(HPRF)t... Target detection is an important research content in the radar field.At present,efforts are being made to optimize the precision of detection information.In this paper,we use the high pulse repetition frequency(HPRF)transmission method and orthogonal biphase coded signals in each pulse to avoid velocity ambiguity and range ambiguity of radar detection.In addition,We also apply Walsh matrix and genetic algorithm(GA)to generate satisfying orthogonal biphase coded signals with low auto-correlation sidelobe peak and cross-correlation peak,which make the results more accurate.In a radar receiver,data rearrangement of echo signals is performed,and then pulse compression and moving target detection(MTD)are utilized to get the final velocity and range information of a target without velocity ambiguity and range ambiguity.Besides,a small transmitting pulse time width is adopted to reduce the working blind area,and two different high pulse repetition frequencies(HPRFs)are adopted to solve the problem of range eclipse.Simulation results finally prove the effectiveness and feasibility of the proposed method. 展开更多
关键词 Biphase coded velocity ambiguity range ambiguity genetic algorithm range eclipse
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Effects of ambiguity on innovation strategies
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作者 Hwa‑Sung Kim 《Financial Innovation》 2023年第1期1813-1839,共27页
Technological innovations significantly influence individual firms and other innova-tions,such as financial innovations.The future of a firm depends on its innovation investment strategy.According to the literature,in... Technological innovations significantly influence individual firms and other innova-tions,such as financial innovations.The future of a firm depends on its innovation investment strategy.According to the literature,innovation investments are affected by ambiguity.This study examines how ambiguity affects the innovation strategies of managers.We show that the innovation strategies of ambiguity-averse managers differ from those of ambiguity-neutral managers.Unlike ambiguity-neutral managers,ambiguity-averse managers consider a broader variety of innovation strategies for a wider range of future innovation arrival times.Regarding the profitability of a future innovation,ambiguity-averse managers delay the investment decision until the profit-ability of the innovation is less ambiguous.Moreover,we examine innovation strategies under various conditions,including the risk of innovation outdatedness,management disputes,and the varying volatility of innovations. 展开更多
关键词 Technological innovation ambiguity Innovation strategy
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The Subduction Structure Beneath the New Britain Island Arc and the Adjacent Region from Double-Difference Tomography
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作者 ZHANG Hao GONG Wei +2 位作者 XING Junhui XU Chong LI Chaoyang 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期107-118,共12页
We applied double-difference tomography to relocate seismic events and determine the lithospheric velocity structure beneath the New Britain Island arc and the South Bismarck Sea Basin,based on the local P wave arriva... We applied double-difference tomography to relocate seismic events and determine the lithospheric velocity structure beneath the New Britain Island arc and the South Bismarck Sea Basin,based on the local P wave arrival time dataset collected by the International Seismological Centre.Results of the seismic relocation and velocity inversion show that the subduction of Solomon Sea Plate along the New Britain Trench is spatially different above 150 km,and the subduction angle of the slab on the west side is higher than that on the east side.The relocated earthquakes also show that there are double seismic zones at the depths of about 30–90km beneath the New Britain Island Arc.The velocity structure shows that the dehydration of the subducting slab caused the low-velocity anomalies in mantle wedge above the slab,which are associated with the magmatic activities around the New Guinea-New Britain Island arc.Moreover,it shows that there is another low-velocity anomaly zone beneath the Bismarck mid-oceanic ridge with spatial variation.Beneath the west of the Bismarck mid-oceanic ridge,the low-velocity anomaly is weakly connected to the subducted Solomon Sea slab.Conversely,the low-velocity anomaly beneath the Manus Sea Basin is highly intertwined to the subducting slab and its mantle wedge,indicating that the subduction of the Solomon Sea Plate might be a key deep dynamic factor that drives the spreading of the Manus Sea Basin and the separation of the Bismarck Plate. 展开更多
关键词 New Britain Trench Bismarck Sea Basin Manus Sea Basin double-difference tomography
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Ambiguity function analysis and side peaks suppression of Link16 signal based passive radar
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作者 BAI Luyang WANG Jun CHEN Xiaoling 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1526-1536,共11页
Link16 data link is the communication standard of the joint tactical information distribution system(JTIDS)used by the U.S.military and North Atlantic Treaty Organization,which is applied as the opportunistic illumina... Link16 data link is the communication standard of the joint tactical information distribution system(JTIDS)used by the U.S.military and North Atlantic Treaty Organization,which is applied as the opportunistic illuminator for passive radar in this paper.The time-domain expression of the Link16 signal is established,and its ambiguity function expression is derived.The timedelay dimension and Doppler dimension side peaks of which lead to the appearance of the false target during target detection.To solve the problem,the time-delay dimension and Doppler dimension side peaks suppression methods are proposed.For the problem that the conventional mismatched filter(MMF)cannot suppress the time-delay dimension side peaks,a neighborhood MMF(NMMF)is proposed.Experimental results demonstrate the effectiveness of the proposed methods. 展开更多
关键词 passive radar ambiguity function LINK16 mismatched filter(MMF)
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基于Radon-Ambiguity变换的多分量LFM信号检测与参数估计 被引量:12
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作者 刘爱芳 朱晓华 +1 位作者 陆锦辉 刘中 《南京理工大学学报》 EI CAS CSCD 北大核心 2004年第4期409-413,共5页
介绍了Radon -Ambiguity变换 (RAT)的定义和基本性质 ,结合解线调技术提出了一种基于RAT的线性调频 (LFM )信号检测与参数估计方法 ,该方法能用较少的计算量完成对LFM信号的检测与参数估计。为解决多分量条件下LFM信号分量之间交叉项的... 介绍了Radon -Ambiguity变换 (RAT)的定义和基本性质 ,结合解线调技术提出了一种基于RAT的线性调频 (LFM )信号检测与参数估计方法 ,该方法能用较少的计算量完成对LFM信号的检测与参数估计。为解决多分量条件下LFM信号分量之间交叉项的影响 ,基于逐次消去思想 ,提出了一种基于RAT的多分量LFM信号检测与参数估计算法 ,它可以有效地解决强度相差较大的多分量LFM信号的检测和参数估计问题。仿真实验结果验证了该算法的有效性。 展开更多
关键词 Radon—ambiguity变换 线性调频信号 参数估计
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分级计算迭代在Radon-Ambiguity变换和分数阶Fourier变换对chirp信号检测及参数估计的应用 被引量:18
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作者 郭斌 张红雨 《电子与信息学报》 EI CSCD 北大核心 2007年第12期3024-3026,共3页
该文在分析Radon-Ambiguity变换(RAT)和分数阶Fourier变换对chirp信号的检测和参数估计的基础上,建立了多分量chirp信号检测和参数估计系统模型,提出了分级计算迭代方法,大大减少了计算量,提高了运算速度。
关键词 分数阶FOURIER变换 Radon—ambiguity变换 CHIRP信号
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基于Radon-Ambiguity变换和分数阶傅里叶变换的chirp信号检测及多参数估计 被引量:43
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作者 赵兴浩 陶然 +1 位作者 周思永 王越 《北京理工大学学报》 EI CAS CSCD 北大核心 2003年第3期371-374,377,共5页
研究噪声环境中chirp信号的检测以及多参数估计问题.分析和比较了Radon-Wigner变换(RWT)法、Radon-Ambiguity变换(RAT)法和分数阶傅里叶变换(FRFT)扫描法的优缺点.提出了一种基于RAT和FRFT的新算法,并提出了幅度估计的一种适合于计算的... 研究噪声环境中chirp信号的检测以及多参数估计问题.分析和比较了Radon-Wigner变换(RWT)法、Radon-Ambiguity变换(RAT)法和分数阶傅里叶变换(FRFT)扫描法的优缺点.提出了一种基于RAT和FRFT的新算法,并提出了幅度估计的一种适合于计算的表达式.最后通过计算机仿真验证了该方法的有效性.这种方法与RWT法和FRFT扫描法相比,将chirp信号的检测问题变为一维搜索问题,简化了计算,与单纯的RAT法相比,有效地解决了chirp信号的初始频率和幅度的估计问题.因此,适合于对chirp信号多参数联合估计. 展开更多
关键词 分数阶傅里叶变换 RADON-ambiguity变换 CHIRP信号 多参数估计
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基于Radon-ambiguity变换的ISAR成像算法 被引量:4
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作者 刘爱芳 刘中 陆锦辉 《现代雷达》 CSCD 北大核心 2003年第6期12-14,34,共4页
非匀速旋转目标和机动目标成像是逆合成孔径雷达 (ISAR)技术的一个重点和难点 ,经典的距离 -多普勒(RD)算法对其成像效果不佳。本文首先分析了ISAR成像回波信号模型 ,然后在对目标多普勒变化曲线作一阶近似的条件下提出了基于Radon Ambi... 非匀速旋转目标和机动目标成像是逆合成孔径雷达 (ISAR)技术的一个重点和难点 ,经典的距离 -多普勒(RD)算法对其成像效果不佳。本文首先分析了ISAR成像回波信号模型 ,然后在对目标多普勒变化曲线作一阶近似的条件下提出了基于Radon Ambiguity变换 (RAT)的ISAR成像算法。最后进行仿真实验 ,仿真实验结果表明了该方法的有效性。 展开更多
关键词 RADON-ambiguity变换 逆合成孔径雷达 ISAR RAT 成像算法 线性调频信号
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基于局部Radon-Ambiguity变换的ARM检测技术 被引量:2
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作者 方前学 王永良 王首勇 《系统工程与电子技术》 EI CSCD 北大核心 2008年第11期2151-2154,共4页
针对反辐射导弹(anti-radiation missile,ARM)雷达回波信号的调频率特性,提出了基于局部Radon-Ambiguity变换(RAT)的ARM检测方法。该方法对导弹的初速度不敏感,也不需要对导弹加速度进行多通道相位补偿预处理。通过将RAT局部化,进一步... 针对反辐射导弹(anti-radiation missile,ARM)雷达回波信号的调频率特性,提出了基于局部Radon-Ambiguity变换(RAT)的ARM检测方法。该方法对导弹的初速度不敏感,也不需要对导弹加速度进行多通道相位补偿预处理。通过将RAT局部化,进一步缩小了检测区域和运算量,提高了检测效率。检测性能分析和仿真实验表明,该方法能够在较低信噪比环境下有效地检测ARM目标信号。 展开更多
关键词 目标检测 局部Radon-ambiguity变换 线性调频信号 反辐射导弹
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在单脉冲内利用Hough-Ambiguity变换估计目标加速度研究
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作者 贾舒宜 王国宏 杜文超 《海军航空工程学院学报》 2008年第1期33-36,共4页
根据雷达发射恒定载频信号时匀加速目标的回波为线性调频(LFM)信号的特点,研究了在单脉冲内基于Hough—Ambiguity变换(HAT)估计目标径向加速度的问题。首先,采用Hough—Ambiguity变换得到信号的调频斜率;进而,根据调频斜率估计... 根据雷达发射恒定载频信号时匀加速目标的回波为线性调频(LFM)信号的特点,研究了在单脉冲内基于Hough—Ambiguity变换(HAT)估计目标径向加速度的问题。首先,采用Hough—Ambiguity变换得到信号的调频斜率;进而,根据调频斜率估计出目标径向加速度;最后,仿真实验结果验证了方法的有效性。 展开更多
关键词 Hough—ambiguity变换 径向加速度 线性调频信号
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在单脉冲内基于Radon-Ambiguity变换的加速度估计方法研究 被引量:4
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作者 贾舒宜 王国宏 杜文超 《宇航学报》 EI CAS CSCD 北大核心 2008年第3期989-994,共6页
根据雷达发射恒定载频信号时匀加速目标回波为线性调频(LFM)信号的特点,研究了在单脉冲内基于Radon-Ambiguity变换(RAT)估计目标径向加速度的问题,首先采用Radon-Ambiguity变换(RAT)得到信号的调频斜率,进而根据调频斜率估计出目标径向... 根据雷达发射恒定载频信号时匀加速目标回波为线性调频(LFM)信号的特点,研究了在单脉冲内基于Radon-Ambiguity变换(RAT)估计目标径向加速度的问题,首先采用Radon-Ambiguity变换(RAT)得到信号的调频斜率,进而根据调频斜率估计出目标径向加速度。分析了加速度分辨率和加速度估计效率,讨论了信号时长和搜索步长对测量加速度精度的影响,最后仿真实验结果验证了方法的有效性。 展开更多
关键词 RADON-ambiguity变换 径向加速度 线性调频信号 RADON-WIGNER变换 WIGNER-HOUGH变换
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基于Radon-Ambiguity变换和解调频技术的SAR运动目标检测 被引量:2
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作者 姜义成 韩逸飞 《现代雷达》 CSCD 北大核心 2005年第5期41-44,共4页
详细探讨了合成孔径雷达中运动目标的检测问题,根据机载合成孔径雷达运动目标回波信号的特点,提出了基于Radon- Ambiguity变换和解调频技术的一种新的机载运动目标检测方法,给出了动目标检测、参数估计的主要步骤,分析了在单目标和多目... 详细探讨了合成孔径雷达中运动目标的检测问题,根据机载合成孔径雷达运动目标回波信号的特点,提出了基于Radon- Ambiguity变换和解调频技术的一种新的机载运动目标检测方法,给出了动目标检测、参数估计的主要步骤,分析了在单目标和多目标情况下的检测性能。该方法与常用的Wigner- Ville分布和Radon变换结合的方法相比计算量明显减少,在多目标情况下能够较好地抑制交叉项,提高检测性能。且使用解调频技术与RAT相配合,解决了单纯RAT无法估计Chirp信号初始频率的问题。仿真试验结果证明了算法的有效性。 展开更多
关键词 合成孔径雷达 运动目标检测 RADON-ambiguity变换 解调频技术
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Ambiguity及成因初探 被引量:1
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作者 顾菊华 《楚雄师范学院学报》 2003年第6期67-70,共4页
英语歧义现象随处可见,它直接影响人们对句子的正确理解和翻译。本文从音歧义、词汇歧义、句法歧义、修辞 和标点歧义等五方面对英语的歧义进行分类、分析,并论证了歧义现象及其成因。
关键词 歧义 音韵 句法 修辞 标点
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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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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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A Systemic-Functional Approach to English Ambiguity
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作者 张静 《海外英语》 2014年第6X期254-255,共2页
This thesis chooses the theory of rank scale and the theory of meta-function in the framework of Systemic-Functional Grammar(SFG)to study ambiguity.It firstly analyzes ambiguities occurring at the rank of morpheme,wor... This thesis chooses the theory of rank scale and the theory of meta-function in the framework of Systemic-Functional Grammar(SFG)to study ambiguity.It firstly analyzes ambiguities occurring at the rank of morpheme,word or phrase.Then it studies ambiguities at the rank of clause,from ideational ambiguity to textual ambiguity.This study shows that SFG can give a systematic and comprehensive interpretation of English ambiguity. 展开更多
关键词 English ambiguity SFG RANK scale meta-function
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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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