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Mathematical Model of Embodied Symbols: Cognition and Perceptual Symbol System
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作者 Leonid Perlovsky Roman Ilin 《Journal of Behavioral and Brain Science》 2012年第2期195-220,共26页
A mathematical model of perceptual symbol system is developed. This development requires new mathematical methods of dynamic logic (DL), which have overcome limitations of classical artificial intelligence and connect... A mathematical model of perceptual symbol system is developed. This development requires new mathematical methods of dynamic logic (DL), which have overcome limitations of classical artificial intelligence and connectionist approaches. The paper discusses these past limitations, relates them to combinatorial complexity (exponential explosion) of algorithms in the past, and relates it further to the static nature of classical logic. DL is a process-logic;its salient property is evolution of vague representations into crisp. We first consider one aspect of PSS: situation learning from object perceptions. Next DL is related to PSS mechanisms of concepts, simulators, grounding, embodiment, productiveity, binding, recursion, and to the mechanisms relating embodied-grounded and amodal symbols. We discuss DL capability for modeling cognition on multiple levels of abstraction. PSS is extended toward interaction between cognition and language. Experimental predictions of the theory are discussed. They might influence experimental psychology and impact future theoretical developments in cognitive science, including knowledge representation, and mechanisms of interaction between perception, cognition, and language. All mathematical equations are also discussed conceptually, so mathematical understanding is not required. Experimental evidence for DL and PSS in brain imaging is discussed as well as future research directions. 展开更多
关键词 Perceptual symbol system EMBODIED COGNITION PERCEPTION Knowledge Representation Grounded symbolS Dynamic Logic
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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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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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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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Low-Complexity Joint Channel Estimation and Symbol Detection for OFDMA Systems 被引量:4
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作者 Rui Xin Zuyao Ni +2 位作者 Sheng Wu Linling Kuang Chunxiao Jiang 《China Communications》 SCIE CSCD 2019年第7期49-60,共12页
In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation... In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation and symbol detection leverage the framework of expectation propagation(EP)and belief propagation(BP)with the aid of Gaussian approximation,respectively.Furthermore,to reduce the computation complexity involved in channel estimation,the matrix inversion is transformed into a series of diagonal matrix inversions through the Sherman-Morrison formula.Simulation experiments show that the proposed algorithm can reduce the pilot overhead by about 50%,compared with the traditional linear minimum mean square error(LMMSE)algorithm,and can approach to the bit error rate(BER)performance bound of perfectly known channel state information within 0.1 dB. 展开更多
关键词 JOINT channel estimation and symbol detection MESSAGE PASSING OFDMA
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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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Symbols detection for frequency-selective V-BLAST OFDM systems
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作者 WuXiaojun LiXing WangJilong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期418-425,共8页
As the combining form of the orthogonal frequency-division multiplexing (OFDM) technique and the vertical Bell Labs layered space-time (V-BLAST) architecture, the V-BLAST OFDM system can better meet the demand of next... As the combining form of the orthogonal frequency-division multiplexing (OFDM) technique and the vertical Bell Labs layered space-time (V-BLAST) architecture, the V-BLAST OFDM system can better meet the demand of next-generation (NextG) broadband mobile wireless multimedia communications. The symbols detection problem of the V-BLAST OFDM system is investigated under the frequency-selective fading environment. The joint space-frequency demultiplexing operation is proposed in the V-BLAST OFDM system. Successively, one novel half-rate rotational invariance joint space-frequency coding scheme for the V-BLAST OFDM system is proposed. By elegantly exploiting the above rotational invariance property, we derive one direct symbols detection scheme without knowing channels state information (CSI) for the frequency-selective V-BLAST OFDM system. Extensive simulation results demonstrate the validity of the novel half-rate rotational invariance joint space-frequency coding scheme and the performance of the direct symbols detection scheme. 展开更多
关键词 orthogonal frequency-division multiplexing vertical Bell Labs layered space-time architecture symbols detection frequency-selective fading joint space-frequency demultiplexing rotational invariance joint space-frequency coding.
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Application of Heuristic (1-Opt local Search) and Metaheuristic (Ant Colony Optimization) Algorithms for Symbol Detection in MIMO Systems
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作者 Kiran Khurshid Safwat Irteza +1 位作者 Adnan Ahmed Khan S. I. Shah 《Communications and Network》 2011年第4期200-209,共10页
Heuristic and metaheuristic techniques are used for solving computationally hard optimization problems. Local search is a heuristic technique while Ant colony optimization (ACO), inspired by the ants' foraging beh... Heuristic and metaheuristic techniques are used for solving computationally hard optimization problems. Local search is a heuristic technique while Ant colony optimization (ACO), inspired by the ants' foraging behavior, is one of the most recent metaheuristic technique. These techniques are used for solving optimization problems. Multiple-Input Multiple-Output (MIMO) detection problem is an NP-hard combinatorial optimization problem. We present heuristic and metaheuristic approaches for symbol detection in multi-input multi-output (MIMO) system. Since symbol detection is an NP-hard problem so ACO is particularly attractive as ACO algorithms are one of the most successful strands of swarm intelligence and are suitable for applications where low complexity and fast convergence is of absolute importance. Maximum Likelihood (ML) detector gives optimal results but it uses exhaustive search technique. We show that 1-Opt and ACO based detector can give near-optimal bit error rate (BER) at much lower complexity levels. Comparison of ACO with another nature inspired technique, Particle Swarm Optimization (PSO) is also discussed. The simulation results suggest that the proposed detectors give an acceptable performance complexity trade-off in comparison with ML and VBLAST detectors. 展开更多
关键词 Spatial MULTIPLEXING system 1-Opt ACO Multi-Input MULTI-OUTPUT systems symbol Detection
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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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Application of Blank Symbols in Japanese Architecture and Indoor Designs
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作者 Zhang Zhanzhi Wu Pengjun Zheng Shaojiang 《Contemporary Social Sciences》 2023年第3期145-155,共11页
A symbol is an expression of meaning,while blank symbols express special meanings.By focusing on the application of blank symbols in Japanese architecture and indoor designs,we analyzed the aesthetic principles in Jap... A symbol is an expression of meaning,while blank symbols express special meanings.By focusing on the application of blank symbols in Japanese architecture and indoor designs,we analyzed the aesthetic principles in Japanese architecture and indoor designs from the perspective of semiotics,such as“Kongji,”“Emptiness,”and“Dying out,”and their minimalist and pure design concepts.Traditional Chinese culture was also further explored,especially the profound influence of the“Chan sect”and the philosophy of“unity of heaven and mankind”on Japanese architecture and designs.This study aims to facilitate the coexistence and mutual appreciation of Chinese and Japanese architectural designs. 展开更多
关键词 Blank symbols Japanese culture architectural designs indoor designs traditional Chinese aesthetics
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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 Influence of Clothing on Characterization from Symbolism: Taking The Scarlet Letter, Daisy Miller, and Dry September as Examples
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作者 HU Ya-ling 《Journal of Literature and Art Studies》 2023年第12期978-982,共5页
In the novels, the clothing worn by the characters are symbols made and used by the authors to express the characters’ personality and deepen the theme, and grasping their symbolism helps to enter into the interior o... In the novels, the clothing worn by the characters are symbols made and used by the authors to express the characters’ personality and deepen the theme, and grasping their symbolism helps to enter into the interior of the novels and understand their essence. This paper will analyze and interpret the clothing of typical female characters in The Scarlet Letter, Daisy Miller and Dry September from the perspective of symbolism, so as to illustrate how the symbolism of clothing, as a kind of symbols, shapes the image of the main characters. 展开更多
关键词 symbolISM CLOTHING CHARACTERIZATION The Scarlet Letter Daisy Miller Dry September
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The Application of Symbolism in Domenico Starnone’s Novel Lacci
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作者 ZOU Jiamei 《Cultural and Religious Studies》 2023年第3期142-146,共5页
In the Italian novel Lacci,the young husband abandoned his wife and lived with another woman.Although the marriage has been maintained under the stress of tense relations,friction and cracks have long existed and brok... In the Italian novel Lacci,the young husband abandoned his wife and lived with another woman.Although the marriage has been maintained under the stress of tense relations,friction and cracks have long existed and broken their peaceful life.This betrayal story restores the whole story from three perspectives through the eyes of the husband,the wife,and the memory of two children.It also reveals the indifferent and uncommunicable situations experienced by everyone in the family.The shoelace that appeared repeatedly in this article not only symbolizes the entangled and chaotic relationship between husband and wife,but also symbolizes the parent-child relationship that has long been broken but still tied up with each other;another image,the cat,not only symbolizes the seductive lover in the eyes of the husband,but also represents himself who pursues the satisfaction of desire.At the same time,cat also implies the disintegration of this marriage from inside to outside.In short,in this suffocating marriage novel,shoelace symbolizes order,while cat symbolizes chaos.The cat who keeps breaking in wore away their trust and emotion,and in the end,the two people in marriage can only bind reluctantly with shoelaces and hurt each other. 展开更多
关键词 Domenico Starnone Lacci symbolISM
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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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Joint Estimation of Carrier Frequency and Phase Offset Based on Pilot Symbols in Quasi-Constant Envelope OFDM Satellite Systems 被引量:3
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作者 Cheng Wang Gaofeng Cui +1 位作者 Weidong Wang Yinghai Zhang 《China Communications》 SCIE CSCD 2017年第7期184-194,共11页
Spectral efficiency and energy efficiency are two important performance indicators of satellite systems. The Quasi-Constant Envelope Orthogonal Frequency Division Multiplexing(QCE-OFDM) technique can achieve both high... Spectral efficiency and energy efficiency are two important performance indicators of satellite systems. The Quasi-Constant Envelope Orthogonal Frequency Division Multiplexing(QCE-OFDM) technique can achieve both high spectral efficiency and low peak-to-average power ratio(PAPR). Therefore, the QCE-OFDM technique is considered as a promising candidate multi-carrier technique for satellite systems. However, the Doppler effect will cause the carrier frequency offset(CFO), and the non-ideal oscillator will cause the carrier phase offset(CPO) in satellite systems. The CFO and CPO will further result in the bit-error-rate(BER) performance degradation. Hence, it is important to estimate and compensate the CFO and CPO. This paper analyzes the effects of both CFO and CPO in QCE-OFDM satellite systems. Furthermore, we propose a joint CFO and CPO estimation method based on the pilot symbols in the frequency domain. In addition, the optimal pilot symbol structure with different pilot overheads is designed according to the minimum Cramer-Rao bound(CRB) criterion. Simulation results show that the estimation accuracy of the proposed method is close to the CRB. 展开更多
关键词 载波频率偏移 正交频分复用 卫星系统 导频符号 联合估计 相位偏移 包络 恒定
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The Wonders of the Wall:The Great Wall is a powerful symbol that represents the heroic spirit of the Chinese people
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作者 FORTUNE ABANG 《ChinAfrica》 2023年第5期56-57,共2页
While getting a chance to visit the Great Wall of China may not be easy,it is a memorable experience for everyone who manages to get there.And the value of the Great Wall is not confined to tourists;it is also signifi... While getting a chance to visit the Great Wall of China may not be easy,it is a memorable experience for everyone who manages to get there.And the value of the Great Wall is not confined to tourists;it is also significant for those interested in learning about the preservation of the historic site as a unique symbol of Chinese civilisation. 展开更多
关键词 symbol GREAT EVERYONE
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