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Computing large deviation prefactors of stochastic dynamical systems based on machine learning
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作者 李扬 袁胜兰 +1 位作者 陆凌宏志 刘先斌 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期364-373,共10页
We present a large deviation theory that characterizes the exponential estimate for rare events in stochastic dynamical systems in the limit of weak noise.We aim to consider a next-to-leading-order approximation for m... We present a large deviation theory that characterizes the exponential estimate for rare events in stochastic dynamical systems in the limit of weak noise.We aim to consider a next-to-leading-order approximation for more accurate calculation of the mean exit time by computing large deviation prefactors with the aid of machine learning.More specifically,we design a neural network framework to compute quasipotential,most probable paths and prefactors based on the orthogonal decomposition of a vector field.We corroborate the higher effectiveness and accuracy of our algorithm with two toy models.Numerical experiments demonstrate its powerful functionality in exploring the internal mechanism of rare events triggered by weak random fluctuations. 展开更多
关键词 machine learning large deviation prefactors stochastic dynamical systems rare events
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LARGE DEVIATIONS FOR TOP EIGENVALUES OFβ-JACOBI ENSEMBLES AT SCALING TEMPERATURES
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作者 雷良贞 马宇韬 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1767-1780,共14页
Letλ=(λ_(1),…,λ_(n))beβ-Jacobi ensembles with parameters p_(1),p_(2),n andβ,withβvarying with n.Set■.Suppose that■and 0≤σγ<1.We offer the large deviation for p_(1)+p_(2)/p_(1)■λ_(i)whenγ>0 via the... Letλ=(λ_(1),…,λ_(n))beβ-Jacobi ensembles with parameters p_(1),p_(2),n andβ,withβvarying with n.Set■.Suppose that■and 0≤σγ<1.We offer the large deviation for p_(1)+p_(2)/p_(1)■λ_(i)whenγ>0 via the large deviation of the corresponding empirical measure and via a direct estimate,respectively,whenγ=0. 展开更多
关键词 β-Jacobi ensemble large deviation Wachter law extremal eigenvalue
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A novel lattice model integrating the cooperative deviation of density and optimal flux under V2X environment
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作者 彭光含 罗春莉 +1 位作者 赵红专 谭惠丽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期626-633,共8页
A novel lattice hydrodynamic model is proposed by integrating the cooperative deviation of density and optimal flux under vehicle to X(V2X) environment. According to the theoretical analysis, the stability conditions ... A novel lattice hydrodynamic model is proposed by integrating the cooperative deviation of density and optimal flux under vehicle to X(V2X) environment. According to the theoretical analysis, the stability conditions and the mKdV equations affected by the cooperative deviation of traffic information are explored. And the density wave, hysteresis loop and energy consumption of the traffic flow have been investigated via numerical simulation. The results indicate that the cooperative deviation of density and optimal flux can effectively alleviate the traffic congestion. More importantly, our new consideration can reduce fuel consumption and exhaust emission under the V2X environment. 展开更多
关键词 traffic flow lattice hydrodynamic model cooperative deviation
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Assessment of Deviation in Quality of Steel Reinforcing Bars Used in Some Building Sites in Cameroon
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作者 Patrick Che Bame Bell Emmanuel Yamb Billong Ndigui 《World Journal of Engineering and Technology》 2023年第4期917-931,共15页
The present work evaluated the deviations in the quality of steel reinforcing bars in terms of markings, diameter, yield strength and ductility in order to facilitate the drawing up of a yield strength value for the C... The present work evaluated the deviations in the quality of steel reinforcing bars in terms of markings, diameter, yield strength and ductility in order to facilitate the drawing up of a yield strength value for the Cameroon National Annex to Eurocode 2. The methodology of the work started with the collection of steel samples from various active building project sites in four different towns viz: Bamenda, Douala, Maroua and Yaoundé and testing their tensile strength and elongation using a Universal Testing Machine and also carrying out the bending test. Results show that bars without marked manufacturer’s name fell all the tests. Other results show that 52% of all the steel had yield stresses below 400 Mpa and the highest deviation in the yield strengths was 22.50%. The study recommends that properly marked grade 500 steel bars should be adopted in the Cameroon national annex to Eurocode 2. 展开更多
关键词 Eurocode 2 National Annex Reinforcement Steel deviationS Yield Strengths
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Application Research of an Intelligent Detection Algorithm for Vehicle Trajectory Route Deviation
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作者 Jianfei Luo Yadong Xing +2 位作者 Cheng Chen Weiqing Zhang Zhongcheng Wu 《Journal of Computer and Communications》 2023年第10期1-11,共11页
In the vehicle trajectory application system, it is often necessary to detect whether the vehicle deviates from the specified route. Trajectory planning in the traditional route deviation detection is defined by the d... In the vehicle trajectory application system, it is often necessary to detect whether the vehicle deviates from the specified route. Trajectory planning in the traditional route deviation detection is defined by the driver through the mobile phone navigation software, which plays a more auxiliary driving role. This paper presents a method of vehicle trajectory deviation detection. Firstly, the manager customizes the trajectory planning and then uses big data technologies to match the deviation between the trajectory planning and the vehicle trajectory. Finally, it achieves the supervisory function of the manager on the vehicle track route in real-time. The results show that this method could detect the vehicle trajectory deviation quickly and accurately, and has practical application value. 展开更多
关键词 Vehicle Positioning Terminal Vehicle Trajectory Route deviation Real-Time Segmentation Analysis Algorithm
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A LARGE DEVIATION PRINCIPLE FOR THE STOCHASTIC GENERALIZED GINZBURG-LANDAU EQUATION DRIVEN BY JUMP NOISE
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作者 王冉 张贝贝 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期505-530,共26页
In this paper,we establish a large deviation principle for the stochastic generalized Ginzburg-Landau equation driven by jump noise.The main difficulties come from the highly non-linear coefficient and the jump noise.... In this paper,we establish a large deviation principle for the stochastic generalized Ginzburg-Landau equation driven by jump noise.The main difficulties come from the highly non-linear coefficient and the jump noise.Here,we adopt a new sufficient condition for the weak convergence criterion of the large deviation principle,which was initially proposed by Matoussi,Sabbagh and Zhang(2021). 展开更多
关键词 large deviation principle weak convergence method stochastic generalized Ginzburg-Landau equation Poisson random measure
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Effect of Froude similitude deviation on curved channel simulations: A case study in the Middle Yangtze River
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作者 Xiao-ting Yang Qian-qian Shang +3 位作者 Hui Xu Guo-bin Li Ya-jun Gao Qi-lin Yang 《Water Science and Engineering》 EI CAS CSCD 2023年第3期289-294,共6页
Froude similitude and friction similitude are the two crucial similarity conditions that are often used in physical-scale modeling of rivers.However,models often deviate from Froude similitude when dealing with real-w... Froude similitude and friction similitude are the two crucial similarity conditions that are often used in physical-scale modeling of rivers.However,models often deviate from Froude similitude when dealing with real-world situations.This study developed several fixed-bed river models with various curvatures to determine the effect of Froude similitude deviation on curved channel modeling.Models were constructed according to the characteristics of the Middle Yangtze River.Differences in longitudinal slope,transverse slope,and main stream line location were measured by varying Froude similitude deviation.The deviations of longitudinal slope and velocity were negligible because friction similitude was accounted for.The transverse slope varied significantly with the Froude similitude deviation,and the main stream line varied with the curvature and Froude similitude deviation.Formulae were derived to estimate the slope deviation.These analyses helped to clarify the feasibility of the method of Froude similitude deviation for curved channels. 展开更多
关键词 Fixed-bed river model Froude similitude deviation Flow movement Water surface slope Middle Yangtze river
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Modified inferior oblique anterior transposition for dissociated vertical deviation combined with superior oblique palsy:A case report
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作者 Yao Zong Ze Wang +1 位作者 Wen-Lan Jiang Xian Yang 《World Journal of Clinical Cases》 SCIE 2023年第12期2796-2802,共7页
BACKGROUND Inferior oblique anterior transposition(IOAT)has emerged as an effective surgery in the management of dissociated vertical deviation(DVD)combined with superior oblique palsy(SOP).Traditional IOAT usually pr... BACKGROUND Inferior oblique anterior transposition(IOAT)has emerged as an effective surgery in the management of dissociated vertical deviation(DVD)combined with superior oblique palsy(SOP).Traditional IOAT usually provides satisfactory primary position alignment and simultaneously restricts the superior floating phenomenon.However,it also increases the risk of the anti-elevation syndrome and narrowing of the palpebral fissure in straight-ahead gaze,especially after the unilateral operation.CASE SUMMARY We report the outcomes of the modified unilateral IOAT in two patients with unilateral DVD combined with SOP.The anterior-nasal fibers of the inferior oblique muscle were attached at 9 mm posterior to the corneal limbus along the temporal board of the inferior rectus muscle,the other fibers were attached a further 5 mm temporal to the anterior-nasal fibers.Postoperatively,both hypertropia and floating were improved,and no obvious complications occurred.CONCLUSION In these cases,the modified unilateral IOAT was an effective and safe surgical method for treating DVD with SOP. 展开更多
关键词 Anterior transposition Inferior oblique muscles Dissociated vertical deviation Superior oblique palsy Anti-elevation syndrome Case report
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The Inheritance and Deviation of the Subjective Construction“You Bei X Dao(有被X到)”
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作者 YANG Yaqin 《Sino-US English Teaching》 2023年第2期80-84,共5页
Sentence“bei”(“被”字句)and“bei xx”(被xx)provide syntactic and semantic basis for the generation of the construction“You Bei X Dao(有被x到)”.They are in a continuum and have family similarity.The sentence“bei... Sentence“bei”(“被”字句)and“bei xx”(被xx)provide syntactic and semantic basis for the generation of the construction“You Bei X Dao(有被x到)”.They are in a continuum and have family similarity.The sentence“bei”is a typical member,while“bei xx”is an atypical member.Because the construction“You Bei X Dao”has a single function and less attention,it is at the edge of the continuum and is a marginal member.However,it has certain research value in the inheritance and innovation of“bei”and“bei xx”. 展开更多
关键词 “bei”sentence “bei xx” construction“You Bei X Dao” INHERITANCE deviation
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Influence of highway space alignment continuous degradation in 3- dimensional space on autonomous vehicle trajectory deviation based on PreScan simulation
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作者 Xiao-Fei Wang Nathanael Melkisedek Coulibaly Qiang Zeng 《Digital Transportation and Safety》 2023年第2期77-88,共12页
The advent of autonomous vehicles(AVs)is expected to transform the current transportation system into a safe and reliable one.The existing infrastructures,operational criteria,and design method were developed to meet ... The advent of autonomous vehicles(AVs)is expected to transform the current transportation system into a safe and reliable one.The existing infrastructures,operational criteria,and design method were developed to meet the requirements of human drivers.However,previous studies have shown that in the traditional horizontal and vertical combined design methods,where the two-dimensional alignment elements change,there are varying changes in curvature and torsion,which cause the continuous degradation of the spatial curve and torsion.This continuous degradation will inevitably cause changes in the trajectory of Autonomous Vehicles(AVs),thereby affecting driving safety.Therefore,studying the characteristics of autonomous vehicles trajectory deviation has theoretical significance for optimizing highway alignment safety design.Driving simulation tests were performed by using PreScan and Simulink to calibrate the lateral deviation.A machine learning approach called the Gradient Boosting Decision Tree(GBDT)algorithm was implemented to build a model and express the relationship between space alignment parameters and lane deviation.The results showed that the AV’s driving trajectory is significantly affected by the space alignment factors when the vehicle is driving in the inner lane,the downhill section,and the left-turn section.These findings will provide a novel perspective for road safety research based on autonomous vehicle driving trajectories. 展开更多
关键词 Autonomous Vehicles(AVs) Trajectory deviation(TD) Traffic Safety Spatial Alignment Prescan CURVATURE TORSION
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IMPROVED FOURIER ALGORITHM FOR CORRECTING POWER SYSTEM FREQUENCY DEVIATION 被引量:1
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作者 姜惠兰 杨维 +2 位作者 徐建强 刘梅 仇晓锋 《Transactions of Tianjin University》 EI CAS 2001年第3期192-196,共5页
On the basis of high precision requirement for input signals in the power system protection and control system,this paper,only for the influence of power system frequency deviation on extracting fundamental harmonic,s... On the basis of high precision requirement for input signals in the power system protection and control system,this paper,only for the influence of power system frequency deviation on extracting fundamental harmonic,studies the amplitude error of Fourier algorithm,presents a method of correcting frequency deviation,and further derives the formulas of improved Fourier algorithm.The simulation results verified the effectiveness of the algorithm,it not only can greatly weaken the influence of frequency deviation,but also increase the precision of the power system protection and control.As a result the study in this paper has practical application value. 展开更多
关键词 power system protection and control frequency deviation Fourier algorithm
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A novel method for eliminating rotation deviation in sequential images mosaic
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作者 陈芳 陈恺 +1 位作者 赵斌文 史金飞 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期434-437,共4页
To eliminate rotation deviation of sequential images mosaic when measuring linear dimensions of large scale parts with computer vision, a novel algorithm based on the chain code searching method is proposed. After ima... To eliminate rotation deviation of sequential images mosaic when measuring linear dimensions of large scale parts with computer vision, a novel algorithm based on the chain code searching method is proposed. After image preprocessing, including image filtering, image segmentation, and edge detection, the chain code length of the contour line can be searched out by the proposed method. Then, the angle from the contour line to the coordinate axis is computed with the length of the contour line. After that, the sequence is rotated in the opposite direction and the rotation deviation is eliminated. It is prepared for the next mosaic of sequences in eliminating shifting deviation. Experiments are carried out on parts with a linear profile rotating angle from 0° to 9°. The results show that compared with the commonly used Hough transform, the new method has higher precision and faster speed, which is important in realizing online high precision measurements of large scale parts with a linear profile. 展开更多
关键词 sequential images mosaic linear profile chain code rotation deviation
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Precise large deviation result for heavy-tailed random sums and applications to risk theory
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作者 杨洋 林金官 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期498-501,共4页
The differences between two sequences of nonnegative independent and identically distributed random variables with sub-exponential tails and the random index are studied. The random index is a strictly stationary rene... The differences between two sequences of nonnegative independent and identically distributed random variables with sub-exponential tails and the random index are studied. The random index is a strictly stationary renewal counting process generated by some negatively associated random variables. Using a revised large deviation result of partial sums, the elementary renewal theorem and the central limit theorem of negatively associated random variables, a precise large deviation result is derived for the random sums. The result is applied to the customer-arrival-based insurance risk model. Some uniform asymptotics for the ruin probabilities of an insurance company are obtained as the number of customers or the time tends to infinity. 展开更多
关键词 precise large deviation random sum sub-exponential distribution renewal counting process customer-arrival-based insurance risk model
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Deviation in Advertising English from a Stylistic Perspective
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作者 罗敏 《英语广场(学术研究)》 2012年第10期15-17,共3页
Advertising English is viewed as an English style with such functional factors as attention value, readability, memorability, selling power. Commercial advertisements are the major concern of this paper. Deviation, na... Advertising English is viewed as an English style with such functional factors as attention value, readability, memorability, selling power. Commercial advertisements are the major concern of this paper. Deviation, namely the violation to the norms of a language, frequently appears in advertisements and can meet requirements of the style of advertising English. Due to limited space, this paper focuses on deviation on the phonological, graphological, lexical, grammatical, and semantic level. Analyzing deviation in advertising English can promote readers' aesthetic and appreciative ability and encourage advertisers to create advertisements with more efficiency, novelty, innovation in more effective language. 展开更多
关键词 advertising English deviation STYLISTIC VIOLATION NORM
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Stylistic Analysis of Rossetti's Song with the Technique of Deviation
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作者 胡争艳 《海外英语》 2013年第4X期167-168,199,共3页
Song is one of Christina Georgina Rossetti's most outstanding death poems,dealing with the main themes that she concerns:death,love and religion.This paper tries to use the technique of deviation that refers to vi... Song is one of Christina Georgina Rossetti's most outstanding death poems,dealing with the main themes that she concerns:death,love and religion.This paper tries to use the technique of deviation that refers to violations to the standard language and readers'expectations to interpret this poem's stylistic features from the aspects of grammar,phonology,image,theme and narrative point of view.Through the stylistic analysis with the method of deviation,its solemn theme is exposed clearly. 展开更多
关键词 STYLISTIC analysis deviation LOVE DEATH
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Edge detection in the potential field using the correlation coefficients of multidirectional standard deviations 被引量:4
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作者 徐梦龙 杨长保 +2 位作者 吴燕冈 陈竞一 郇恒飞 《Applied Geophysics》 SCIE CSCD 2015年第1期23-34,120,121,共14页
Most edge-detection methods rely on calculating gradient derivatives of the potential field, a process that is easily affected by noise and is therefore of low stability. We propose a new edge-detection method named c... Most edge-detection methods rely on calculating gradient derivatives of the potential field, a process that is easily affected by noise and is therefore of low stability. We propose a new edge-detection method named correlation coefficient of multidirectional standard deviations(CCMS) that is solely based on statistics. First, we prove the reliability of the proposed method using a single model and then a combination of models. The proposed method is evaluated by comparing the results with those obtained by other edge-detection methods. The CCMS method offers outstanding recognition, retains the sharpness of details, and has low sensitivity to noise. We also applied the CCMS method to Bouguer anomaly data of a potash deposit in Laos. The applicability of the CCMS method is shown by comparing the inferred tectonic framework to that inferred from remote sensing(RS) data. 展开更多
关键词 Edge detection Correlation coefficient multidirectional standard deviation Bouguer anomaly
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Deviation Theories and Applications in Poetry Analysis
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作者 肖蓉 《科技信息》 2011年第8期I0142-I0142,共1页
Poetry is prominent for its stylistic characteristics since texts themselves are the carrier of meaning,an analysis of the stylistic features of poems is conducive to the understanding and interpretation of them.It is... Poetry is prominent for its stylistic characteristics since texts themselves are the carrier of meaning,an analysis of the stylistic features of poems is conducive to the understanding and interpretation of them.It is of great significance to learn something about stylistics if we want to explore the meaning of poetry,this kind of method can also be used to analyze other literary works. 展开更多
关键词 诗歌 英语 文学作品 分析方法
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LARGE DEVIATIONS AND MODERATE DEVIATIONS FOR m-NEGATIVELY ASSOCIATED RANDOM VARIABLES 被引量:8
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作者 胡亦钧 明瑞星 杨文权 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期886-896,共11页
M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large devi... M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large deviation principles and moderate deviation upper bounds for stationary m-negatively associated random variables are proved. Kolmogorov-type and Marcinkiewicz-type strong laws of large numbers as well as the three series theorem for m-negatively associated random variables are also given. 展开更多
关键词 negatively associated random variables stationary sequence strong law of large numbers large deviations moderate deviations
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MODERATE DEVIATIONS AND LARGEDE VIATIONS FOR A TEST OF SYMMETRY BASED ON KERNEL DENSITY ESTIMATOR 被引量:5
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作者 何晓霞 高付清 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期665-674,共10页
Let fn be a non-parametric kernel density estimator based on a kernel function K. and a sequence of independent and identically distributed random variables taking values in R. The goal of this article is to prove mod... Let fn be a non-parametric kernel density estimator based on a kernel function K. and a sequence of independent and identically distributed random variables taking values in R. The goal of this article is to prove moderate deviations and large deviations for the statistic sup |fn(x) - fn(-x) |. 展开更多
关键词 Symmetry test kernel estimator moderate deviations large deviations
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An Analysis of the Linguistic Deviation in Chapter X of Oliver Twist 被引量:3
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作者 刘聪 《海外英语》 2013年第19期239-241,277,共4页
Charles Dickens is one of the greatest critical realist writers of the Victorian Age.In language,he is often compared with William Shakespeare for his adeptness with the vernacular and large vocabulary.Charles Dickens... Charles Dickens is one of the greatest critical realist writers of the Victorian Age.In language,he is often compared with William Shakespeare for his adeptness with the vernacular and large vocabulary.Charles Dickens achieved a recognizable place among English writers through the use of the stylistic features in his fictional language.Oliver Twist is the best representative of Charles Dickens’style,which makes it the most appropriate choice for the present stylistic study on Charles Dickens.No one who has ever read the dehumanizing workhouse scenes of Oliver Twist and the dark,criminal underworld life can forget them.This thesis attempts to investigate Oliver Twist through the approach of modern stylistics,particularly the theory of linguistic devia tion.This thesis consists of an introduction,the main body and a conclusion.The introduction offers a brief summary of the com ments on Charles Dickens and Chapter X of Oliver Twist,introduces the newly rising linguistic deviation theories,and brings about the theories on which this thesis settles.The main body explores the deviation effects produced from four aspects:lexical deviation,grammatical deviation,graphological deviation,and semantic deviation.It endeavors to show Dickens’manipulating language and the effects achieved through this manipulation.The conclusion mainly sums up the previous analysis,and reveals the theme of the novel,positive effect of linguistic deviation and significance of deviation application. 展开更多
关键词 deviation LEXICAL GRAMMATICAL graphological semant
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