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Improving the Effectiveness of Image Classification Structural Methods by Compressing the Description According to the Information Content Criterion
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作者 Yousef Ibrahim Daradkeh Volodymyr Gorokhovatskyi +1 位作者 Iryna Tvoroshenko Medien Zeghid 《Computers, Materials & Continua》 SCIE EI 2024年第8期3085-3106,共22页
The research aims to improve the performance of image recognition methods based on a description in the form of a set of keypoint descriptors.The main focus is on increasing the speed of establishing the relevance of ... The research aims to improve the performance of image recognition methods based on a description in the form of a set of keypoint descriptors.The main focus is on increasing the speed of establishing the relevance of object and etalon descriptions while maintaining the required level of classification efficiency.The class to be recognized is represented by an infinite set of images obtained from the etalon by applying arbitrary geometric transformations.It is proposed to reduce the descriptions for the etalon database by selecting the most significant descriptor components according to the information content criterion.The informativeness of an etalon descriptor is estimated by the difference of the closest distances to its own and other descriptions.The developed method determines the relevance of the full description of the recognized object with the reduced description of the etalons.Several practical models of the classifier with different options for establishing the correspondence between object descriptors and etalons are considered.The results of the experimental modeling of the proposed methods for a database including images of museum jewelry are presented.The test sample is formed as a set of images from the etalon database and out of the database with the application of geometric transformations of scale and rotation in the field of view.The practical problems of determining the threshold for the number of votes,based on which a classification decision is made,have been researched.Modeling has revealed the practical possibility of tenfold reducing descriptions with full preservation of classification accuracy.Reducing the descriptions by twenty times in the experiment leads to slightly decreased accuracy.The speed of the analysis increases in proportion to the degree of reduction.The use of reduction by the informativeness criterion confirmed the possibility of obtaining the most significant subset of features for classification,which guarantees a decent level of accuracy. 展开更多
关键词 Description reduction description relevance DESCRIPTOR image classification information content keypoint processing speed
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Investigations on High-Speed Flash Boiling Atomization of Fuel Based on Numerical Simulations
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作者 Wei Zhong Zhenfang Xin +1 位作者 Lihua Wang Haiping Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1427-1453,共27页
Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pr... Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure.However,when the outlet speed of the nozzle exceeds 400 m/s,investigating high-speed flash boiling atomization(HFBA)becomes quite challenging.This difficulty arises fromthe involvement ofmany complex physical processes and the requirement for a very fine mesh in numerical simulations.In this study,an HFBA model for gasoline direct injection(GDI)is established.This model incorporates primary and secondary atomization,as well as vaporization and boilingmodels,to describe the development process of the flash boiling spray.Compared to lowspeed FBA,these physical processes significantly impact HFBA.In this model,the Eulerian description is utilized for modeling the gas,and the Lagrangian description is applied to model the droplets,which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates.Under various conditions,numerical solutions of the Sauter mean diameter(SMD)for GDI show good agreement with experimental data,validating the proposed model’s performance.Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process.Numerical analyses of the velocity field,temperature field,vapor mass fraction distribution,particle size distribution,and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution.This effect is conducive to the refinement of spray particles and enhances atomization. 展开更多
关键词 High-speed flash boiling atomization numerical simulations Eulerian description Lagrangian description gasoline direct injection
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Method for detector description conversion from DD4hep to Filmbox
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作者 Zhao-Yang Yuan Tian-Zi Song +3 位作者 Yu-Jie Zeng Kai-Xuan Huang Yu-Mei Zhang Zheng-Yun You 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期115-126,共12页
DD4hep serves as a generic detector description toolkit recommended for offline software development in next-generation high-energy physics(HEP)experiments.Conversely,Filmbox(FBX)stands out as a widely used 3D modelin... DD4hep serves as a generic detector description toolkit recommended for offline software development in next-generation high-energy physics(HEP)experiments.Conversely,Filmbox(FBX)stands out as a widely used 3D modeling file format within the 3D software industry.In this paper,we introduce a novel method that can automatically convert complex HEP detector geometries from DD4hep description into 3D models in the FBX format.The feasibility of this method was dem-onstrated by its application to the DD4hep description of the Compact Linear Collider detector and several sub-detectors of the super Tau-Charm facility and circular electron-positron collider experiments.The automatic DD4hep–FBX detector conversion interface provides convenience for further development of applications,such as detector design,simulation,visualization,data monitoring,and outreach,in HEP experiments. 展开更多
关键词 Detector description DD4hep FBX GEOMETRY Offline software
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Enhancing constitutive description and workability characterization of Mg alloy during hot deformation using machine learning-based Arrhenius-type model
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作者 Jinchuan Long Lei Deng +6 位作者 Junsong Jin Mao Zhang Xuefeng Tang Pan Gong Xinyun Wang Gangfeng Xiao Qinxiang Xia 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期3003-3023,共21页
Hot deformation is a commonly employed processing technique to enhance the ductility and workability of Mg alloy.However,the hot deformation of Mg alloy is highly sensitive to factors such as temperature,strain rate,a... Hot deformation is a commonly employed processing technique to enhance the ductility and workability of Mg alloy.However,the hot deformation of Mg alloy is highly sensitive to factors such as temperature,strain rate,and strain,leading to complex flow behavior and an exceptionally narrow processing window for Mg alloy.To overcome the shortcomings of the conventional Arrhenius-type(AT)model,this study developed machine learning-based Arrhenius-type(ML-AT)models by combining the genetic algorithm(GA),particle swarm optimization(PSO),and artificial neural network(ANN).Results indicated that when describing the flow behavior of the AQ80 alloy,the PSO-ANN-AT model demonstrates the most prominent prediction accuracy and generalization ability among all ML-AT and AT models.Moreover,an activation energy-processing(AEP)map was established using the reconstructed flow stress and activation energy fields based on the PSO-ANN-AT model.Experimental validations revealed that this AEP map exhibits superior predictive capability for microstructure evolution compared to the one established by the traditional interpolation methods,ultimately contributing to the precise determination of the optimum processing window.These findings provide fresh insights into the accurate constitutive description and workability characterization of Mg alloy during hot deformation. 展开更多
关键词 Constitutive description Workability characterization Machine learning Mg alloy Hot deformation
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A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region
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作者 Yuhua Yin Zhiliang Liu +1 位作者 Bin Guo Mingjian Zuo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期229-241,共13页
Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal phases.Within the ostensibly stable healthy phase,the reliance o... Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal phases.Within the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly discernment.To address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe regions.The proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere center.By leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two tasks.Subsequent experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping trade-offs.In the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation metrics.Their theoretical analysis inspires us to focus on feature extraction and data collection to achieve improvements.The proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions. 展开更多
关键词 Bearing condition monitoring Anomaly detection Safe region Support vector data description
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Trends in Event Understanding and Caption Generation/Reconstruction in Dense Video:A Review
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作者 Ekanayake Mudiyanselage Chulabhaya Lankanatha Ekanayake Abubakar Sulaiman Gezawa Yunqi Lei 《Computers, Materials & Continua》 SCIE EI 2024年第3期2941-2965,共25页
Video description generates natural language sentences that describe the subject,verb,and objects of the targeted Video.The video description has been used to help visually impaired people to understand the content.It... Video description generates natural language sentences that describe the subject,verb,and objects of the targeted Video.The video description has been used to help visually impaired people to understand the content.It is also playing an essential role in devolving human-robot interaction.The dense video description is more difficult when compared with simple Video captioning because of the object’s interactions and event overlapping.Deep learning is changing the shape of computer vision(CV)technologies and natural language processing(NLP).There are hundreds of deep learning models,datasets,and evaluations that can improve the gaps in current research.This article filled this gap by evaluating some state-of-the-art approaches,especially focusing on deep learning and machine learning for video caption in a dense environment.In this article,some classic techniques concerning the existing machine learning were reviewed.And provides deep learning models,a detail of benchmark datasets with their respective domains.This paper reviews various evaluation metrics,including Bilingual EvaluationUnderstudy(BLEU),Metric for Evaluation of Translation with Explicit Ordering(METEOR),WordMover’s Distance(WMD),and Recall-Oriented Understudy for Gisting Evaluation(ROUGE)with their pros and cons.Finally,this article listed some future directions and proposed work for context enhancement using key scene extraction with object detection in a particular frame.Especially,how to improve the context of video description by analyzing key frames detection through morphological image analysis.Additionally,the paper discusses a novel approach involving sentence reconstruction and context improvement through key frame object detection,which incorporates the fusion of large languagemodels for refining results.The ultimate results arise fromenhancing the generated text of the proposedmodel by improving the predicted text and isolating objects using various keyframes.These keyframes identify dense events occurring in the video sequence. 展开更多
关键词 Video description video to text video caption sentence reconstruction
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Enhancing Cross-Lingual Image Description: A Multimodal Approach for Semantic Relevance and Stylistic Alignment
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作者 Emran Al-Buraihy Dan Wang 《Computers, Materials & Continua》 SCIE EI 2024年第6期3913-3938,共26页
Cross-lingual image description,the task of generating image captions in a target language from images and descriptions in a source language,is addressed in this study through a novel approach that combines neural net... Cross-lingual image description,the task of generating image captions in a target language from images and descriptions in a source language,is addressed in this study through a novel approach that combines neural network models and semantic matching techniques.Experiments conducted on the Flickr8k and AraImg2k benchmark datasets,featuring images and descriptions in English and Arabic,showcase remarkable performance improvements over state-of-the-art methods.Our model,equipped with the Image&Cross-Language Semantic Matching module and the Target Language Domain Evaluation module,significantly enhances the semantic relevance of generated image descriptions.For English-to-Arabic and Arabic-to-English cross-language image descriptions,our approach achieves a CIDEr score for English and Arabic of 87.9%and 81.7%,respectively,emphasizing the substantial contributions of our methodology.Comparative analyses with previous works further affirm the superior performance of our approach,and visual results underscore that our model generates image captions that are both semantically accurate and stylistically consistent with the target language.In summary,this study advances the field of cross-lingual image description,offering an effective solution for generating image captions across languages,with the potential to impact multilingual communication and accessibility.Future research directions include expanding to more languages and incorporating diverse visual and textual data sources. 展开更多
关键词 Cross-language image description multimodal deep learning semantic matching reward mechanisms
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Enhancing Image Description Generation through Deep Reinforcement Learning:Fusing Multiple Visual Features and Reward Mechanisms
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作者 Yan Li Qiyuan Wang Kaidi Jia 《Computers, Materials & Continua》 SCIE EI 2024年第2期2469-2489,共21页
Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually imp... Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually impaired.This study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of images.Our method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more closely.Our approach comprises three key architectures.Firstly,it utilizes Residual Network 101(ResNet-101)and Faster Region-based Convolutional Neural Network(Faster R-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature fusion.Secondly,the Transformer model is engaged to derive contextual semantic features from textual data.Finally,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward functions.Compared with the image description method that relies on deep learning,the score of Bilingual Evaluation Understudy(BLEU-1)is 0.762,which is 1.6%higher,and the score of BLEU-4 is 0.299.Consensus-based Image Description Evaluation(CIDEr)scored 0.998,Recall-Oriented Understudy for Gisting Evaluation(ROUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image description.Future research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems. 展开更多
关键词 Image description deep reinforcement learning attention mechanism
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耦合拉格朗日-欧拉方法及其在海洋工程中的应用
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作者 钱志浩 杨腾茂 刘谋斌 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第2期366-397,共32页
Combining the strengths of Lagrangian and Eulerian descriptions,the coupled Lagrangian–Eulerian methods play an increasingly important role in various subjects.This work reviews their development and application in o... Combining the strengths of Lagrangian and Eulerian descriptions,the coupled Lagrangian–Eulerian methods play an increasingly important role in various subjects.This work reviews their development and application in ocean engineering.Initially,we briefly outline the advantages and disadvantages of the Lagrangian and Eulerian descriptions and the main characteristics of the coupled Lagrangian–Eulerian approach.Then,following the developmental trajectory of these methods,the fundamental formulations and the frameworks of various approaches,including the arbitrary Lagrangian–Eulerian finite element method,the particle-in-cell method,the material point method,and the recently developed Lagrangian–Eulerian stabilized collocation method,are detailedly reviewed.In addition,the article reviews the research progress of these methods with applications in ocean hydrodynamics,focusing on free surface flows,numerical wave generation,wave overturning and breaking,interactions between waves and coastal structures,fluid–rigid body interactions,fluid–elastic body interactions,multiphase flow problems and visualization of ocean flows,etc.Furthermore,the latest research advancements in the numerical stability,accuracy,efficiency,and consistency of the coupled Lagrangian–Eulerian particle methods are reviewed;these advancements enable efficient and highly accurate simulation of complicated multiphysics problems in ocean and coastal engineering.By building on these works,the current challenges and future directions of the hybrid Lagrangian–Eulerian particle methods are summarized. 展开更多
关键词 Coupled Lagrangian–Eulerian description Ocean engineering Wave–structure interaction Particle methods Arbitrary Lagrangian–Eulerian(ALE)methods Particle-in-cell(PIC) Material point method(MPM) Lagrangian–Eulerian stabilized collocation method(LESCM)
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Unified Description of the Three Stable Particles in Self-Action Allows Determination of Their Relative Masses
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作者 Yair Goldin Halfon 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期185-196,共12页
The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials... The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials, A<sub>μ</sub>. We assumed that the fundamental form of the Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-S<sub>μ</sub>)Ψ=0 should describe the stable particles (the electron, the proton and the dark-matter-particle (dmp)) bound to themselves under the action of their own potentials S<sub>μ</sub>. The new equation reveals that self energy is consequence of self action, it also reveals that the spin angular momentum is consequence of the dynamic structure of the stable particles. The quantitative results are the determination of their relative masses as well as the determination of the electromagnetic coupling constant. 展开更多
关键词 Electron in Self Action Electron-Dark-Matter Particle Mass Ratio Analytic Description Dark-Matter-Particle
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Modeling the Physical Parameters of Solenoids for MEMS Applications
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作者 Mykhaylo Andriychuk Bohdan Karkulovskyi Yarko Kuleshnyk 《Journal of Applied Mathematics and Physics》 2024年第5期1819-1834,共16页
The paper is devoted to study of the electrical parameters of the motion parts of the MEMS such as solenoids. The analytical background is given in order to describe the influence of the electrical field components on... The paper is devoted to study of the electrical parameters of the motion parts of the MEMS such as solenoids. The analytical background is given in order to describe the influence of the electrical field components on the forces, which are result of interaction of the electromagnetic (EM) field components with the parts of motion devices of MEMS. The given analytical formulas open the ability to calculate the self-inductance of the microsolenoids of the different kind, as well as the stored energy of such motion devices, that could be used for the modeling and optimization of parameters of running devices of MEMS such as actuators, sensors etc. 展开更多
关键词 EM Description Motion Microdevice Microsolenoid Stored Energy Computational Data
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Describing a Baryon as a Composition of Bound Stated and Unbound Stated Sea-Quarks
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作者 Teruo Kurai 《Journal of Modern Physics》 2024年第10期1586-1602,共17页
We propose the revised description of a baryon as a composition of bound stated sea-quarks and unbound stated sea-quarks from the previously proposed description of baryon as a meson pair. The purpose of this article ... We propose the revised description of a baryon as a composition of bound stated sea-quarks and unbound stated sea-quarks from the previously proposed description of baryon as a meson pair. The purpose of this article is to show the following two possibilities. The first one shows the qualitative explanation to support our description of a nucleon as a pair of pions and the second one is that it gives an explanation of ALICE results that the pTdependence of Λc+/D0ratio is 0.5. Each isospin group is constructed of both baryons and antibaryons. This way of construction is consistent with that of mesons. The results obtained are listed in tables. This shows that the generalized Gell-Mann-Nishijima relation equation holds under the condition that the baryon number is 0. 展开更多
关键词 Baryon Description Baryon Isospin Baryon Mass
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Natural Numbers and the Strong Goldbach Conjecture
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第9期3208-3236,共29页
This study introduces the representation of natural number sets as row vectors and pretends to offer a new perspective on the strong Goldbach conjecture. The natural numbers are restructured and expanded with the incl... This study introduces the representation of natural number sets as row vectors and pretends to offer a new perspective on the strong Goldbach conjecture. The natural numbers are restructured and expanded with the inclusion of the zero element as the source of a strong Goldbach conjecture reformulation. A prime Boolean vector is defined, pinpointing the positions of prime numbers within the odd number sequence. The natural unit primality is discussed in this context and transformed into a source of quantum-like indetermination. This approach allows for rephrasing the strong Goldbach conjecture, framed within a Boolean scalar product between the prime Boolean vector and its reverse. Throughout the discussion, other intriguing topics emerge and are thoroughly analyzed. A final description of two empirical algorithms is provided to prove the strong Goldbach conjecture. 展开更多
关键词 Natural Numbers Prime Numbers Vector Description of Natural Numbers Prime Boolean Vectors Primality of the Natural Unit Strong Goldbach’s Conjecture Vector Reversal Pairing Conjecture Natural Matrix Squeezing
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主动分布式Web服务注册机制研究与实现 被引量:37
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作者 杜宗霞 怀进鹏 《软件学报》 EI CSCD 北大核心 2006年第3期454-462,共9页
服务注册库作为SOA(serviceorientedarchitecture)结构中的重要组成部分,目前主要使用的UDDI(universaldescription,discoveryandintegration)及基于UDDI的UBR(universalbusinessregistry)的实际使用情况较差.主要原因在于:UBR的注册信... 服务注册库作为SOA(serviceorientedarchitecture)结构中的重要组成部分,目前主要使用的UDDI(universaldescription,discoveryandintegration)及基于UDDI的UBR(universalbusinessregistry)的实际使用情况较差.主要原因在于:UBR的注册信息在各注册节点间完全复制,导致其随着服务数量的增加变得较难管理和维护;另一方面,目前UDDI只能提供被动的目录服务,而统计研究发现,很少有组织或个人在发布服务后主动更新信息,这就造成了其上服务信息的有效性差.提出了一种主动分布式服务注册机制(adUDDI),利用服务主动监测机制提高注册库中服务信息的实时有效性;利用分布式结构减轻统一注册中心的负担.通过实验分析说明,此方法可提高SOA结构的可用性,为基于Web服务构建可靠业务中间件提供了基础. 展开更多
关键词 UDDI(universal description.discovery and integration) WEB服务 主动监测 分布式结构
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Description logics for fuzzy ontologies on semantic web 被引量:6
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作者 康达周 徐宝文 +1 位作者 陆建江 李言辉 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期343-347,共5页
To enable representation and reasoning for fuzzy ontologies with expressive fuzzy knowledge on the semantic web, a new fuzzy extension of description logics called the fuzzy description logics with comparison expressi... To enable representation and reasoning for fuzzy ontologies with expressive fuzzy knowledge on the semantic web, a new fuzzy extension of description logics called the fuzzy description logics with comparison expressions (FCDLs) is presented. The syntax and semantics of FCDLs are formally defined, and the forms of axioms and assertions in FCDLs knowledge bases are specified. FCDLs combine both fuzzy concepts from the fuzzy description logics (FDLs) and cut concepts from the extended fuzzy description logics (EFDLs) in the same theory. Furthermore, cut concepts are extended into comparison cut concepts in FCDLs to represent comparison expressions between fuzzy membership degrees, which are often used in practice but not supported by the other fuzzy extensions of description logics. FCDLs have more expressive power than FDLs and EFDLs, and are able to represent expressive fuzzy knowledge and to perform reasoning tasks based on them. Therefore, FCDLs can enable representation and reasoning for fuzzy ontologies with expressive fuzzy knowledge on the semantic web. 展开更多
关键词 semantic web ONTOLOGY description logics FUZZY
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一种面向LBS的电信增值业务生成方法及实现 被引量:7
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作者 杨骎 陈俊亮 孟祥武 《软件学报》 EI CSCD 北大核心 2009年第4期965-974,共10页
基于位置的服务被认为是继短信之后电信增值业务发展的下一次高潮,在前期所提出的一种面向电信增值业务领域的流程描述语言XPL(extended-calling process language)的基础上,进一步提出了一种描述地理信息服务的语言GDL(geography descr... 基于位置的服务被认为是继短信之后电信增值业务发展的下一次高潮,在前期所提出的一种面向电信增值业务领域的流程描述语言XPL(extended-calling process language)的基础上,进一步提出了一种描述地理信息服务的语言GDL(geography description language),GDL可以和XPL配合使用,共同描述基于位置的电信服务.XPL和GDL具有抽象层次高,使用灵活简单,开发业务速度快的特点.还介绍了支持XPL和GDL的业务生成系统.该业务生成系统基于SOA(services-oriented architecture,面向服务的构架),适用于网络融合条件下的业务生成. 展开更多
关键词 业务生成 XPL(extended-calling process language) GDL(geography description language 地理描述语言) 业务上下文 POI(point of interest 兴趣点) 构件 软件复用 SOA(services-oriented architecture 基于服务的构架)
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ESSENTIAL RELATIONSHIP BETWEEN DOMAIN-BASED ONE-CLASS CLASSIFIERS AND DENSITY ESTIMATION 被引量:2
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作者 陈斌 李斌 +1 位作者 冯爱民 潘志松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期275-281,共7页
One-class support vector machine (OCSVM) and support vector data description (SVDD) are two main domain-based one-class (kernel) classifiers. To reveal their relationship with density estimation in the case of t... One-class support vector machine (OCSVM) and support vector data description (SVDD) are two main domain-based one-class (kernel) classifiers. To reveal their relationship with density estimation in the case of the Gaussian kernel, OCSVM and SVDD are firstly unified into the framework of kernel density estimation, and the essential relationship between them is explicitly revealed. Then the result proves that the density estimation induced by OCSVM or SVDD is in agreement with the true density. Meanwhile, it can also reduce the integrated squared error (ISE). Finally, experiments on several simulated datasets verify the revealed relationships. 展开更多
关键词 one-class support vector machine(OCSVM) support vector data description(SVDD) kernel density estimation
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基于3DES的跳频序列族构造方法的VLSI实现 被引量:1
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作者 李赞 蔡觉平 +1 位作者 金力军 常义林 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2004年第4期501-504,580,共5页
基于3DES的迭代型分组密码产生的跳频序列具有好的安全性、随机性、均匀性及频率间隔特性等性能指标,利用VHDL语言有限状态机的设计方法,自顶而下进行系统的模块划分,通过状态机的逐层嵌套和模块的相互调用,完成了基于3DES的跳频序列族... 基于3DES的迭代型分组密码产生的跳频序列具有好的安全性、随机性、均匀性及频率间隔特性等性能指标,利用VHDL语言有限状态机的设计方法,自顶而下进行系统的模块划分,通过状态机的逐层嵌套和模块的相互调用,完成了基于3DES的跳频序列族构造方法的VLSI实现.测试结果表明,使用ALTERAFLEX10K20开发的跳频加密芯片在1 5MHz~24MHz的时钟范围内,均能满足2000跳/秒的高速跳频要求,并且具有运算速度快、占用资源少、输入方式灵活等特点,开发出的芯片已应用于高速跳频通信系统中. 展开更多
关键词 分组密码 跳频序列 VHDL(VHSIC Hardware Description Language) VLSI(Very Large Scale Integrated circuits)
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阻塞斩波三相交交变频电源的FPGA控制实现 被引量:1
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作者 朱虹 潘小波 +2 位作者 陈玲 关越 张庆丰 《电力系统保护与控制》 EI CSCD 北大核心 2014年第21期116-123,共8页
变频技术是重要的节能技术,所以针对低频或转速不恒定的节能设备,提出了基于FPGA数字控制的三相交交直接变频电源技术。用VHDL语言对主控芯片FPGA编写程序,其输出的高频SPWM信号经驱动电路后作为电源和负载间开关MOSFET的控制信号。MOS... 变频技术是重要的节能技术,所以针对低频或转速不恒定的节能设备,提出了基于FPGA数字控制的三相交交直接变频电源技术。用VHDL语言对主控芯片FPGA编写程序,其输出的高频SPWM信号经驱动电路后作为电源和负载间开关MOSFET的控制信号。MOSFET周期性地部分阻塞电源不能达到负载来改变输出电压的频率,同时在放行的时区斩波来改变输出电压的幅值。基于Matlab仿真平台,对系统进行了建模和仿真,仿真结果验证了该技术的正确性。最后给出了频率为7.14 Hz和2.63 Hz的实验波形,实验结果证明了该技术的可行性。 展开更多
关键词 交交变频 Field—Programmable Gate Array(FPGA) 斩波 恒压频比 面积等效 占空比 Very—High-Speed Integrated Circuit Hardware Description Language(VHDL)
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New method for query answering in semantic web 被引量:1
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作者 林培光 刘弘 +1 位作者 樊孝忠 王涛 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期319-323,共5页
To promote the efficiency of knowledge base retrieval based on description logic, the concept of assertional graph (AG), which is directed labeled graph, is defined and a new AG-based retrieval method is put forward... To promote the efficiency of knowledge base retrieval based on description logic, the concept of assertional graph (AG), which is directed labeled graph, is defined and a new AG-based retrieval method is put forward. This method converts the knowledge base and query clause into knowledge AG and query AG by making use of the given rules and then makes use of graph traversal to carry out knowledge base retrieval. The experiment indicates that the efficiency of this method exceeds, respectively, the popular RACER and KAON2 system by 0.4% and 3.3%. This method can obviously promote the efficiency of knowledge base retrieval. 展开更多
关键词 description logic assertional graph semantic web information retrieval
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