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State-Based Opacity Verification of Networked Discrete Event Systems Using Labeled Petri Nets
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作者 Yifan Dong Naiqi Wu Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1274-1291,共18页
The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its behavior... The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its behavior.This paper addresses the verification of current-state,initial-state,infinite-step,and K-step opacity of networked discrete event systems modeled by labeled Petri nets,where communication losses and delays are considered.Based on the symbolic technique for the representation of states in Petri nets,an observer and an estimator are designed for the verification of current-state and initial-state opacity,respectively.Then,we propose a structure called an I-observer that is combined with secret states to verify whether a networked discrete event system is infinite-step opaque or K-step opaque.Due to the utilization of symbolic approaches for the state-based opacity verification,the computation of the reachability graphs of labeled Petri nets is avoided,which dramatically reduces the computational overheads stemming from networked discrete event systems. 展开更多
关键词 INFINITE system symbolic
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Distributional Chaos Occurring on the Set of Proper Positive Upper Banach Density Recurrent Points of One-sided Symbolic Systems
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作者 Yan Jie TANG Jian Dong YIN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2020年第1期66-76,共11页
The purpose of this paper is to show that for one-sided symbolic systems,there exists an uncountable distributionally scrambled set contained in the set of proper positive upper Banach density recurrent points.
关键词 Distributional chaos positive upper Banach density recurrent point one-sided symbolic system
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PERIODIC WINDOWS OF NONLINEAR GEAR SYSTEM BASED ON SYMBOLIC DYNAMICS 被引量:6
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作者 GAO Zhiying SHEN Yunwen LIU Xiaoning 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期434-438,共5页
The periodic window is researched by means of the symbolic dynamics and formal language. Firstly, the proper sampling period is taken and the orbital points of periodic motion are obtained through Poincar6 mapping. Se... The periodic window is researched by means of the symbolic dynamics and formal language. Firstly, the proper sampling period is taken and the orbital points of periodic motion are obtained through Poincar6 mapping. Secondly, according to the method of symbolic dynamics of one-dimensional discrete mapping, the symbolic sequence describing the periodic orbit is obtained. Finally, based on the symbolic sequence, the corresponding model of minimal finite automation is constructed and the entropy is obtained by calculating the maximal eigenvalue of Stefan matrix. The results show that the orbits in periodic windows can be strictly marked by using the method of symbolic dynamics, thus a foundation for control of switching between target orbits is provided. 展开更多
关键词 Nonlinear gear system Periodic window symbolic sequence Finite automation Entropy
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Design of high-performance ion-doped CoP systems for hydrogen evolution:From multi-level screening calculations to experiment 被引量:1
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作者 Xiaofei Cao Siqian Xing +6 位作者 Duo Ma Yuan Tan Yucheng Zhu Jun Hu Yao Wang Xi Chen Zhong Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期307-316,I0007,共11页
Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach... Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach to optimize its performance.However,there is a lack of systematic theoretical studies to reveal the quantitative relationships at the electronic level.Here,we develop a multi-level screening methodology to search for highly stable and active dopants for CoP catalysts.The density functional theory(DFT)calculations and symbolic regression(SR)were performed to investigate the relationship between the adsorption free energy(ΔG_(H^(*)))and 10 electronic parameters.The mathematic formulas derived from SR indicate that the difference of work function(ΔΦ)between doped metal and the acceptor plays the most important role in regulatingΔG_(H^(*)),followed by the d-band center(d-BC)of doped system.The descriptor of HER can be expressed asΔG_(H^(*))=1.59×√|0.188ΔΦ+d BC+0.120|1/2-0.166 with a high determination coefficient(R^(2)=0.807).Consistent with the theoretical prediction,experimental results show that the Al-CoP delivers superior electrocatalytic HER activity with a low overpotential of75 m V to drive a current density of 10 mA cm^(-2),while the overpotentials for undoped CoP,Mo-CoP,and V-CoP are 206,134,and 83 m V,respectively.The current work proves that theΔΦis the most significant regulatory parameter ofΔG_(H^(*))for ion-doped electrocatalysts.This finding can drive the discovery of high-performance ion-doped electrocatalysts,which is crucial for electrocatalytic water splitting. 展开更多
关键词 Design of ion-doped catalyst symbolic regression Density functional theory calculation Hydrogen evolution reaction
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Symbolic generation of the kinematics of multibody systems in EasyDyn: From MuPAD to Xcas/Giac
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作者 Olivier Verlinden Lassaad Ben Fkih Georges Kouroussis 《Theoretical & Applied Mechanics Letters》 CAS 2013年第1期89-94,共6页
In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position.... In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position. Originally, the MuPAD computer algebra system had been retained because it was freely available for non commercial purposes and showed very good technical features.Unfortunately, MuPAD is nowadays only available through commercial channels and needs to be replaced to keep EasyDyn publicly available. This paper presents why Xcas/Giac is finally selected,among other long-term promising projects like Axiom, Maxima, Sage or Yacas. Among the choice criteria, the accessibility, the portability, the ease of use, the automatic export to C language, and the similarity with the -MuPAD language are all considered. The performances of the MuPAD and Xcas/Giac implementations are also compared on some examples.C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi:10.1063/2.13013012] 展开更多
关键词 symbolic multibody systems KINEMATICS computer algebra system open source
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A SYMBOLIC COMPUTATION METHOD TO DECIDE THE COMPLETENESS OF THE SOLUTIONS TO THE SYSTEM OF LINEAR PARTIAL DIFFERENTIAL EQUATIONS
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作者 张鸿庆 谢福鼎 陆斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1134-1139,共6页
A symbolic computation method to decide whether the solutions to the system Of linear partial differential equation is complete via using differential algebra and characteristic set is presented. This is a mechanizati... A symbolic computation method to decide whether the solutions to the system Of linear partial differential equation is complete via using differential algebra and characteristic set is presented. This is a mechanization method, and it can be carried out on the computer in the Maple environment. 展开更多
关键词 differential algebra system of partial differential equation symbolic computation characteristic set
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Crack Growth Rate Model Derived from Domain Knowledge-Guided Symbolic Regression
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作者 Shuwei Zhou Bing Yang +2 位作者 Shoune Xiao Guangwu Yang Tao Zhu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期286-301,共16页
Machine learning(ML)has powerful nonlinear processing and multivariate learning capabilities,so it has been widely utilised in the fatigue field.However,most ML methods are inexplicable black-box models that are diffi... Machine learning(ML)has powerful nonlinear processing and multivariate learning capabilities,so it has been widely utilised in the fatigue field.However,most ML methods are inexplicable black-box models that are difficult to apply in engineering practice.Symbolic regression(SR)is an interpretable machine learning method for determining the optimal fitting equation for datasets.In this study,domain knowledge-guided SR was used to determine a new fatigue crack growth(FCG)rate model.Three terms of the variable subtree ofΔK,R-ratio,andΔK_(th)were obtained by analysing eight traditional semi-empirical FCG rate models.Based on the FCG rate test data from other literature,the SR model was constructed using Al-7055-T7511.It was subsequently extended to other alloys(Ti-10V-2Fe-3Al,Ti-6Al-4V,Cr-Mo-V,LC9cs,Al-6013-T651,and Al-2324-T3)using multiple linear regression.Compared with the three semi-empirical FCG rate models,the SR model yielded higher prediction accuracy.This result demonstrates the potential of domain knowledge-guided SR for building the FCG rate model. 展开更多
关键词 Fatigue crack growth rate Stress intensity factor range Threshold stress intensity factor range R-RATIO symbolic regression Machine learning
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A robust symbol timing strategy for cellular systems
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作者 Yangpeng Dan Jianxin Yi +2 位作者 Xianrong Wan Yunhua Rao Yan Liu 《Digital Communications and Networks》 SCIE CSCD 2023年第3期757-768,共12页
In cellular systems,establishing the initial symbol timing of potential preambles is the first step of a cell search.The envelope fluctuation of the downlink signal hinders the successful timing of conventional symbol... In cellular systems,establishing the initial symbol timing of potential preambles is the first step of a cell search.The envelope fluctuation of the downlink signal hinders the successful timing of conventional symbol timing methods.To solve this problem,a hybrid timing strategy is proposed with two novel detectors,namely the normalized replica-based detector and normalized differential detector.The strategy first detects all potential preambles via the normalized replica-based detector and then employs the normalized differential detector to verify the target preamble,which comes from the target cell and has the highest power.The strategy is unaffected by envelope fluctuation and has computational complexity comparable to that of conventional methods.Simu-lations and real-data tests show that the hybrid timing strategy is robust and practical for initial symbol timing. 展开更多
关键词 Symbol timing SYNCHRONIZATION PREAMBLE Cell search Cellular system Envelope fluctuation
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Training-based symbol detection with temporal convolutional neural network in single-polarized optical communication system
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作者 Yingzhe Luo Jianhao Hu 《Digital Communications and Networks》 SCIE CSCD 2023年第4期920-930,共11页
In order to reduce the physical impairment caused by signal distortion,in this paper,we investigate symbol detection with Deep Learning(DL)methods to improve bit-error performance in the optical communication system.M... In order to reduce the physical impairment caused by signal distortion,in this paper,we investigate symbol detection with Deep Learning(DL)methods to improve bit-error performance in the optical communication system.Many DL-based methods have been applied to such systems to improve bit-error performance.Referring to the speech-to-text method of automatic speech recognition,this paper proposes a signal-to-symbol method based on DL and designs a receiver for symbol detection on single-polarized optical communications modes.To realize this detection method,we propose a non-causal temporal convolutional network-assisted receiver to detect symbols directly from the baseband signal,which specifically integrates most modules of the receiver.Meanwhile,we adopt three training approaches for different signal-to-noise ratios.We also apply a parametric rectified linear unit to enhance the noise robustness of the proposed network.According to the simulation experiments,the biterror-rate performance of the proposed method is close to or even superior to that of the conventional receiver and better than the recurrent neural network-based receiver. 展开更多
关键词 Deep learning Optical communications Symbol detection Temporal convolutional network
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Evolution Performance of Symbolic Radial Basis Function Neural Network by Using Evolutionary Algorithms
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作者 Shehab Abdulhabib Alzaeemi Kim Gaik Tay +2 位作者 Audrey Huong Saratha Sathasivam Majid Khan bin Majahar Ali 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期1163-1184,共22页
Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algor... Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algorithms for training the Symbolic Radial Basis Function Neural Network(SRBFNN)through the behavior’s integration of satisfiability programming.Inspired by evolutionary algorithms,which can iteratively find the nearoptimal solution,different Evolutionary Algorithms(EAs)were designed to optimize the producer output weight of the SRBFNN that corresponds to the embedded logic programming 2Satisfiability representation(SRBFNN-2SAT).The SRBFNN’s objective function that corresponds to Satisfiability logic programming can be minimized by different algorithms,including Genetic Algorithm(GA),Evolution Strategy Algorithm(ES),Differential Evolution Algorithm(DE),and Evolutionary Programming Algorithm(EP).Each of these methods is presented in the steps in the flowchart form which can be used for its straightforward implementation in any programming language.With the use of SRBFNN-2SAT,a training method based on these algorithms has been presented,then training has been compared among algorithms,which were applied in Microsoft Visual C++software using multiple metrics of performance,including Mean Absolute Relative Error(MARE),Root Mean Square Error(RMSE),Mean Absolute Percentage Error(MAPE),Mean Bias Error(MBE),Systematic Error(SD),Schwarz Bayesian Criterion(SBC),and Central Process Unit time(CPU time).Based on the results,the EP algorithm achieved a higher training rate and simple structure compared with the rest of the algorithms.It has been confirmed that the EP algorithm is quite effective in training and obtaining the best output weight,accompanied by the slightest iteration error,which minimizes the objective function of SRBFNN-2SAT. 展开更多
关键词 Satisfiability logic programming symbolic radial basis function neural network evolutionary programming algorithm genetic algorithm evolution strategy algorithm differential evolution algorithm
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Analysis of the Symbolic Meaning of James Joyce’s Araby
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作者 SUN Qiu-yue 《Journal of Literature and Art Studies》 2023年第3期160-164,共5页
Araby is a short story by the famous Irish stream-of-consciousness writer James Joyce.Through a series of images,the novel expresses the theme of the story:the“mental paralysis”of Dubliners and the“spiritual Epiph... Araby is a short story by the famous Irish stream-of-consciousness writer James Joyce.Through a series of images,the novel expresses the theme of the story:the“mental paralysis”of Dubliners and the“spiritual Epiphany”of the little boy,which reflects the spiritual barren of Dubliners at that time.Through the analysis of the symbolic meaning of many images in the work,this paper reveals the social background and religious significance hidden behind the images. 展开更多
关键词 symbolic meaning James Joyce ARABY
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The Symbolic Expression in the Material Form in Public Spaces
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作者 Goda Sūdžiūtė 《Journal of Civil Engineering and Architecture》 2023年第7期337-342,共6页
The article explores the topic of symbolic expression in the physical elements that form urban public spaces.It is done by giving an overview and analysing spaces that hold a widely-recognised symbolic value.The autho... The article explores the topic of symbolic expression in the physical elements that form urban public spaces.It is done by giving an overview and analysing spaces that hold a widely-recognised symbolic value.The author discusses the means of encoding and perceiving meanings in the spacial composition,physical form and materials of its elements,and other aspects that influence the sensory or psychological perception of the observer.At the same time,different theoretical approaches to the perception of space are discussed,addressing not only architectural theory but also the ideas proposed in the fields of philosophy,fenomenology and cultural studies. 展开更多
关键词 Architectural symbolism MEMORIALS public spaces urban spaces
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Binary Program Vulnerability Mining Based on Neural Network
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作者 Zhenhui Li Shuangping Xing +5 位作者 Lin Yu Huiping Li Fan Zhou Guangqiang Yin Xikai Tang Zhiguo Wang 《Computers, Materials & Continua》 SCIE EI 2024年第2期1861-1879,共19页
Software security analysts typically only have access to the executable program and cannot directly access the source code of the program.This poses significant challenges to security analysis.While it is crucial to i... Software security analysts typically only have access to the executable program and cannot directly access the source code of the program.This poses significant challenges to security analysis.While it is crucial to identify vulnerabilities in such non-source code programs,there exists a limited set of generalized tools due to the low versatility of current vulnerability mining methods.However,these tools suffer from some shortcomings.In terms of targeted fuzzing,the path searching for target points is not streamlined enough,and the completely random testing leads to an excessively large search space.Additionally,when it comes to code similarity analysis,there are issues with incomplete code feature extraction,which may result in information loss.In this paper,we propose a cross-platform and cross-architecture approach to exploit vulnerabilities using neural network obfuscation techniques.By leveraging the Angr framework,a deobfuscation technique is introduced,along with the adoption of a VEX-IR-based intermediate language conversion method.This combination allows for the unified handling of binary programs across various architectures,compilers,and compilation options.Subsequently,binary programs are processed to extract multi-level spatial features using a combination of a skip-gram model with self-attention mechanism and a bidirectional Long Short-Term Memory(LSTM)network.Finally,the graph embedding network is utilized to evaluate the similarity of program functionalities.Based on these similarity scores,a target function is determined,and symbolic execution is applied to solve the target function.The solved content serves as the initial seed for targeted fuzzing.The binary program is processed by using the de-obfuscation technique and intermediate language transformation method,and then the similarity of program functions is evaluated by using a graph embedding network,and symbolic execution is performed based on these similarity scores.This approach facilitates cross-architecture analysis of executable programs without their source codes and concurrently reduces the risk of symbolic execution path explosion. 展开更多
关键词 Vulnerability mining de-obfuscation neural network graph embedding network symbolic execution
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SUMS OF DUAL TOEPLITZ PRODUCTS ON THE ORTHOGONAL COMPLEMENTS OF FOCK-SOBOLEV SPACES
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作者 陈泳 Young Joo Lee 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期810-822,共13页
We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of ... We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols. 展开更多
关键词 dual Toeplitz operators Fock-Sobolev spaces symbol map
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Symbolic Meanings of “Rose” in A Rose for Emily 被引量:1
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作者 夏祖贵 《英语广场(学术研究)》 2012年第8期42-45,共4页
A Rose for Emily is one of William Faulkner's most famous short stories.Through the representing of patriarchy influence on Emily,Faulkner shows his readers Emily's tragic life.From the diverse meanings of the... A Rose for Emily is one of William Faulkner's most famous short stories.Through the representing of patriarchy influence on Emily,Faulkner shows his readers Emily's tragic life.From the diverse meanings of the "Rose" to the debated themes,this story has been discussed before.This paper tries to analyze the three stages of Emily's struggle for love in order to represent the symbolism of the "Rose" from the perspective of feminism.It also represents the root of Emily's tragedy and the sympathy for the tragic fate of the Southern women. 展开更多
关键词 A ROSE for EMILY symbolic MEANINGS PATRIARCHY FEMINISM
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Yeats’s Ideals:Women Old and Young
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作者 DONG Qian 《Journal of Literature and Art Studies》 2024年第5期330-334,共5页
William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,... William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,Lady Gregory,and Georgie Hyde-Lees.Even in Yeats’s poetry involved with symbolism,it is worth noting that his employment of symbols has used these women as the archetypes,and that the historical context rendered Yeats’s representations of them in his poetry all the more interesting. 展开更多
关键词 IDEALS WOMEN representation SYMBOLISM OCCULT
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Chinese New Year:A Celebration of Culture and Unity
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作者 SHAHBAZ KHAN 《China Today》 2024年第2期39-41,共3页
Many countries list the Spring Festival as a national holiday,and about one-fifth of humanity celebrates this festival in various ways.THE Chinese New Year,also known as the Spring Festival,is a time-honored social an... Many countries list the Spring Festival as a national holiday,and about one-fifth of humanity celebrates this festival in various ways.THE Chinese New Year,also known as the Spring Festival,is a time-honored social and cultural tradition that has been celebrated for thousands of years.It is a festival that not only marks the inception of a new year in Chinese lunar calendar,but also acts as a symbolic bridge to connect individuals from different cultures and backgrounds. 展开更多
关键词 UNITY symbolic FESTIVAL
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Consumer Culture in The Great Gatsby
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作者 ZHU Yuan-chen 《Journal of Literature and Art Studies》 2024年第2期124-127,共4页
F.Scott Fitzgerald’s The Great Gatsby successfully portrays the“Jazz Age”.In the early 20th century,the United States transitioned from a production-based society to a consumer-based society,leading to an era of un... F.Scott Fitzgerald’s The Great Gatsby successfully portrays the“Jazz Age”.In the early 20th century,the United States transitioned from a production-based society to a consumer-based society,leading to an era of unparalleled prosperity.However,in the context of consumer culture,individuals often transition from being masters of their possessions to becoming enslaved by them.As a result,their behaviours and values become increasingly associated with extravagance and consumption.This paper uses Baudrillard’s theory of consumer society and textual analysis to explore the impact of consumer culture on human beings through the symbolization of men and objectification of women in The Great Gatsby.The meanings embedded in the novel are revealed from a different perspective. 展开更多
关键词 consumer culture SYMBOLS OBJECTIFICATION The Great Gatsby
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Symbols in The Magic Barrel
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作者 FU He-yuan 《Journal of Literature and Art Studies》 2024年第1期48-53,共6页
The article takes the famous modern American Jewish writer Bernard Malamud’s novel The Magic Barrel as the object of study,and uses symbolism to interpret it,analyzing it one by one in terms of the magic barrel,the c... The article takes the famous modern American Jewish writer Bernard Malamud’s novel The Magic Barrel as the object of study,and uses symbolism to interpret it,analyzing it one by one in terms of the magic barrel,the colors,the seasons and the windows,respectively,so as to reveal the process of getting rid of the childishness within the novel’s male protagonist,Leo Finkel,who is maturing,as well as the novel’s Jewish theme of searching for the soul of the self. 展开更多
关键词 SYMBOL magic barrel WINDOW
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Guido Reni’s Infant Bacchus: “In vino veritas”
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作者 Liana De Girolami Cheney 《Journal of Literature and Art Studies》 2024年第1期1-39,共39页
This article delves into the significance of Guido Reni’s Infant Bacchus,created during the Italian Baroque period.By examining historical and iconographic elements,the study aims to interpret the symbolism depicted ... This article delves into the significance of Guido Reni’s Infant Bacchus,created during the Italian Baroque period.By examining historical and iconographic elements,the study aims to interpret the symbolism depicted in the painting.The historical aspects include the birth of Dionysus or Bacchus in classical and Italian Renaissance imagery and literary and visual sources that influenced Reni’s solo painting.The iconographic components encompass the infant’s nude body,the child’s bodily functions,and the attributes associated with Bacchus,the God of Agriculture,Revelry,and Wine,such as the grapevines,grapes,ivy,glass flask,kantharos(wine cup),and wine barrel.The emblematic and cosmological associations of Bacchus’s divinity are considered as well. 展开更多
关键词 Infant Bacchus Greek-Roman mythology emblems optics reflections planetary symbolism Giovanni Belli Andrea Alciato Vincenzo Cartari Cesare Ripa and Guido Reni
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