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The Ethical Nature of Strategic Ambiguity in Organizational Communication
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作者 Livia Durac 《Philosophy Study》 2025年第6期444-453,共10页
Strategic ambiguity came to the attention of researchers specializing in organizational issues a few decades ago,attracting both adherents and opponents.An inherent part of the communication process,strategic clarity ... Strategic ambiguity came to the attention of researchers specializing in organizational issues a few decades ago,attracting both adherents and opponents.An inherent part of the communication process,strategic clarity emerged as a result of strategic thinking,against the challenging background of the need for change,imposed by organizational dynamics.As a communication strategy,the roles of discursive ambiguity refer,among others,to its use in strategy documents,in the plan of relations with other institutional entities,etc.some ethical reflections on this form of communication. 展开更多
关键词 strategic ambiguity CLARITY organization ETHICS
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The“two sessions”:institutional investors selloff to avoid ambiguity
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作者 Jiarui Wang Haijun Yang Shancun Liu 《Financial Innovation》 2025年第1期2378-2402,共25页
We construct a model to examine the time-varying ambiguity of investors.When ambiguity occurs concerning recent news,long(short)position investors who are averse to ambiguity reduce(increase)their holdings,resulting i... We construct a model to examine the time-varying ambiguity of investors.When ambiguity occurs concerning recent news,long(short)position investors who are averse to ambiguity reduce(increase)their holdings,resulting in price drops(rises).We empirically analyze how the“two sessions,”a significant event with high policy ambiguity in China,affect the financial market.Our findings suggest that institutional investors mainly sell their holdings between 15 and 5 days before the meetings.Furthermore,the delay in the“two sessions”in 2020 suggests that these selloffs are driven by ambiguity aversion rather than new information. 展开更多
关键词 Two sessions Selloff ambiguity aversion Institutional investors
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Fake News Detection Based on Cross-Modal Ambiguity Computation and Multi-Scale Feature Fusion
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作者 Jianxiang Cao Jinyang Wu +5 位作者 Wenqian Shang Chunhua Wang Kang Song Tong Yi Jiajun Cai Haibin Zhu 《Computers, Materials & Continua》 2025年第5期2659-2675,共17页
With the rapid growth of socialmedia,the spread of fake news has become a growing problem,misleading the public and causing significant harm.As social media content is often composed of both images and text,the use of... With the rapid growth of socialmedia,the spread of fake news has become a growing problem,misleading the public and causing significant harm.As social media content is often composed of both images and text,the use of multimodal approaches for fake news detection has gained significant attention.To solve the problems existing in previous multi-modal fake news detection algorithms,such as insufficient feature extraction and insufficient use of semantic relations between modes,this paper proposes the MFFFND-Co(Multimodal Feature Fusion Fake News Detection with Co-Attention Block)model.First,the model deeply explores the textual content,image content,and frequency domain features.Then,it employs a Co-Attention mechanism for cross-modal fusion.Additionally,a semantic consistency detectionmodule is designed to quantify semantic deviations,thereby enhancing the performance of fake news detection.Experimentally verified on two commonly used datasets,Twitter and Weibo,the model achieved F1 scores of 90.0% and 94.0%,respectively,significantly outperforming the pre-modified MFFFND(Multimodal Feature Fusion Fake News Detection with Attention Block)model and surpassing other baseline models.This improves the accuracy of detecting fake information in artificial intelligence detection and engineering software detection. 展开更多
关键词 Fake news detection MULTIMODAL cross-modal ambiguity computation multi-scale feature fusion
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A sparse moving array imaging approach for FMCW radar with dualaperture adaptive azimuth ambiguity suppression and adaptive QR decomposition
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作者 Yanwen Han Xiaopeng Yan +3 位作者 Jiawei Wang Sheng Zheng Hongrui Yu Jian Dai 《Defence Technology(防务技术)》 2025年第8期254-271,共18页
Range-azimuth imaging of ground targets via frequency-modulated continuous wave(FMCW)radar is crucial for effective target detection.However,when the pitch of the moving array constructed during motion exceeds the phy... Range-azimuth imaging of ground targets via frequency-modulated continuous wave(FMCW)radar is crucial for effective target detection.However,when the pitch of the moving array constructed during motion exceeds the physical array aperture,azimuth ambiguity occurs,making range-azimuth imaging on a moving platform challenging.To address this issue,we theoretically analyze azimuth ambiguity generation in sparse motion arrays and propose a dual-aperture adaptive processing(DAAP)method for suppressing azimuth ambiguity.This method combines spatial multiple-input multiple-output(MIMO)arrays with sparse motion arrays to achieve high-resolution range-azimuth imaging.In addition,an adaptive QR decomposition denoising method for sparse array signals based on iterative low-rank matrix approximation(LRMA)and regularized QR is proposed to preprocess sparse motion array signals.Simulations and experiments show that on a two-transmitter-four-receiver array,the signal-to-noise ratio(SNR)of the sparse motion array signal after noise suppression via adaptive QR decomposition can exceed 0 dB,and the azimuth ambiguity signal ratio(AASR)can be reduced to below-20 dB. 展开更多
关键词 Frequency modulated continuous wave (FMCW) Sparse motion array Range-azimuth imaging Azimuth ambiguity suppression DAAP Adaptive QR decomposition
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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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Method for integer ambiguity resolution in GPS network RTK 被引量:5
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作者 潘树国 王庆 +1 位作者 柯福阳 邓健 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期491-495,共5页
A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations f... A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations for ambiguity resolution is taken as a reference point. The satellite which has the largest elevation angle with the reference point is selected as a reference satellite. The parameters for constructing the weight matrix of carrier phase observation and the criteria for checking the correctness of integer ambiguity resolution of a network are obtained. Then, the wide ambiguity is calculated by a linear combination method of dualband observation. And the LI ambiguity is obtained by a nonionosphere combination method. The Kalman filter is introduced to refine the floating-point solution of ambiguity and estimate the real-time tropospheric delay. Finally, the cofactor matrix of ambiguity is de-correlated by Z-transformation to reduce the searching space of the integer ambiguity solution and improve the efficiency of the least-squares ambiguity decorrelation adjustment (LAMBDA) algorithm. The experimental results show that this method can reliably obtain the integer ambiguity solution among multi-reference stations with 40 epochs. 展开更多
关键词 network real time kinematic ambiguity troposphere: reference satellite least-squares ambiguity decorrelation adjustment
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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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ALGORITHM FOR AMBIGUITY RESOLUTION IN RANGE AND VELOCITY 被引量:1
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作者 张弓 朱兆达 吕波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期219-223,共5页
For enhancing performances and increasing functions of PD radar, High PRF, medium PRF and low PRF are commonly applied into system ambiguity appeared in range and velocity in some PRF. Based on clustering, a slidin... For enhancing performances and increasing functions of PD radar, High PRF, medium PRF and low PRF are commonly applied into system ambiguity appeared in range and velocity in some PRF. Based on clustering, a sliding window correlator algorithm for resolving the radar object ambiguity in range and velocity is described. Slide window algorithm is a searching algorithm. The probability of ambiguity resolution for targets and the computational efficiency are discussed. The relations between the probability of ambiguity resolution of this algorithm and PRF, the range of interest, and the width of sliding window are analyzed. Simulational results are also given. 展开更多
关键词 PD radar ambiguity resolution sliding window CLUSTERING
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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:44
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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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Ambiguity in our daily language usage in both English and Chinese 被引量:1
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作者 雷春林 《Sino-US English Teaching》 2008年第1期9-14,44,共7页
Ambiguity is a unique linguistic feature and is caused by many factors. This paper first introduces the definitions of ambiguity and then mainly illustrates ambiguity in our daily language usage in both English and Ch... Ambiguity is a unique linguistic feature and is caused by many factors. This paper first introduces the definitions of ambiguity and then mainly illustrates ambiguity in our daily language usage in both English and Chinese from phonetic level and syntactic level. People can learn the relationships among those levels and grasp the rule of learning language. Thus, people can realize the complexity and importance of using language and know that it is not easy to express ideas accurately. 展开更多
关键词 ambiguity phonetic level syntactic level daily language usage
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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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基于Radon-Ambiguity变换的LFM信号时/频差快速联合估计 被引量:1
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作者 杨林森 张子敬 郭付阳 《电波科学学报》 EI CSCD 北大核心 2016年第6期1074-1080,共7页
提出了一种基于Radon-Ambiguity变换(Radon-Ambiguity Transform,RAT)的线性调频(Linear Frequency Modulated,LFM)信号时/频差快速联合估计的算法.根据LFM信号在多个不同角度上的RAT峰值位置建立一组以信号间时差和频差为未知量的方程... 提出了一种基于Radon-Ambiguity变换(Radon-Ambiguity Transform,RAT)的线性调频(Linear Frequency Modulated,LFM)信号时/频差快速联合估计的算法.根据LFM信号在多个不同角度上的RAT峰值位置建立一组以信号间时差和频差为未知量的方程组,求解方程组即可得到时/频差的估计值.对于存在噪声的信号,RAT误差会导致方程组不能直接求解,为了抑制噪声干扰,采用最小二乘法估计时/频差.本文算法无需计算二维平面上各点的模糊函数值,并且由于离散RAT可以通过快速傅里叶变换快速实现,具有所需运算量低的优点.仿真实验表明,相比于常见的基于模糊函数峰值搜索的时/频差估计算法,本文算法在保证时/频差估计精度的同时能够显著提高运算效率. 展开更多
关键词 RADON-ambiguity变换 最小二乘法 时/频差 线性调频信号
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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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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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