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Abstraction and Representation:Form and Meaning in the Philosophy of Images
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作者 YUAN Zhen-wei 《Journal of Literature and Art Studies》 2023年第9期716-720,共5页
This article examines the complex interplay between abstraction and representation in the ontology of images.Images inhabit an in-between space as tangible artifacts that also convey intangible ideas and meanings.The ... This article examines the complex interplay between abstraction and representation in the ontology of images.Images inhabit an in-between space as tangible artifacts that also convey intangible ideas and meanings.The analysis synthesizes perspectives from across the history of philosophy to elucidate how images bridge abstraction and representation through their form and function.It engages with ongoing epistemological and aesthetic debates concerning the dual nature of images.Plato’s theory of ideal forms is outlined as an early attempt to define abstraction.Modern semiotic theories are discussed for their insights into how images create meaning through codes and signs.Phenomenology offers an alternative approach by prioritizing the sensorial,affective impact of images.Poststructuralism problematizes representation in the context of mechanical reproduction and simulacra.While diverse,these philosophical frameworks all grapple with the issues images pose between abstract essence and concrete appearance,conceptual ideas and sensory manifestations.The article reveals the richness of images as liminal constructs that collapse dualisms in their creative interfacing of material forms and immaterial meanings.It concludes that this ontological ambiguity empowers images as mediators between imagination and perception,subjectivity and reality. 展开更多
关键词 abstraction IMAGES SEMIOTICS DUALISM PLATO
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Experimental and Theoretical Study of Hydrogen Atom Abstraction from C2H6 and C4H10 by Zirconium Oxide Clusters Anions 被引量:1
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作者 马嘉璧 吴晓楠 +2 位作者 赵艳霞 丁迅雷 何圣贵 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第2期133-137,I0001,共6页
The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H... The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H- and Zr3O7H- are observed after the reaction. Den-sity functional theory calculations indicate that the hydrogen abstraction is favorable in the reaction of Zr2O5- with C2H6, which supports that the observed Zr2O5H- and Zr3O7H- are due to hydrogen atom abstraction from the alkane molecules. This work shows a newpossible pathway in the reaction of zirconium oxide cluster anions with alkane molecules. 展开更多
关键词 Time of flight mass spectrometry Zirconium oxide cluster anion Reactivity Density functional theory Hydrogen atom abstraction
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Photochemical Hydrogen Abstraction and Electron Transfer Reactions of Tetrachlorobenzoquinone with Pyrimidine Nucleobases
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作者 刘坤辉 吴丽丹 +3 位作者 邹笑然 杨文 杜谦 苏红梅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期580-585,I0004,共7页
Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photoc... Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photochemical reaction dynamics of TCBQ with two pyrimidine type nucleobases (thymine and uracil) upon UVA (355 ran) excitation using the technique of nanosecond time-resolved laser flash photolysis. It has been found that 355 nm excitation populates TCBQ molecules to their triplet state 3TCBQ*, which are highly reactive towards thymine or uracil and undergo two parallel reactions, the hydrogen abstraction and electron transfer, leading to the observed photoproducts of TCBQH. and TCBQ.- in transient absorption spectra. The concomitantly produced nucleobase radicals and radical cations are expected to induce a series of oxidative or strand cleavage damage to DNA afterwards. By characterizing the photochemical hydrogen abstraction and electron transfer reactions, our results provide potentially important molecular reaction mechanisms for understanding the carcinogenic effects of pentachlorophenol and its metabolites TCBQ. 展开更多
关键词 Tetrachlorobenzoquinone THYMINE URACIL Triplet state Hydrogen abstraction Electron transfer Laser flash photolysis
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Theoretical Study on Gas Phase Reactions of OH Hydrogen-Abstraction from Formyl Fluoride with Different Catalysts
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作者 王定美 隆正文 +2 位作者 谭兴凤 龙波 张为俊 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第3期325-334,I0001,共11页
The mechanisms and kinetics of the gas phase reactions that the hydrogen atom in formyl fluoride (FCHO) abstracted by OH in the presence of water, formic acid (FA), or sulfuric acid (SA) are theoretically invest... The mechanisms and kinetics of the gas phase reactions that the hydrogen atom in formyl fluoride (FCHO) abstracted by OH in the presence of water, formic acid (FA), or sulfuric acid (SA) are theoretically investigated at the CCSD(T)/6-311++G(3df, 3pd)//MO6-2X/6- 311++G(3df, 3pd) level of theory. The calculated results show that the barriers of the transition states involving catalysts are lowered to -2.89, -6.25, and -7.76 kcal/mol from 3.64 kcal/mol with respect to the separate reactants, respectively, which reflects that those catalysts play an important role in reducing the barrier of the hydrogen abstraction reaction of FCHO with OH. Additionally, using conventional transition state theory with Eckart tun- neling correction, the kinetic data demonstrate that the entrance channel X…FCHO+OH (X=H2O, FA, or SA) is significantly more favorable than the pathway X…OH+FCHO. More- over, the rate constants of the reactions of FCHO with OH radical with H2O, FA, or SA introduced are computed to be smaller than that of the naked OH+FCHO reaction because the concentration of the formed X…FCHO or X…OH complex is quite low in the atmosphere. 展开更多
关键词 Formyl fluoride Hydrogen abstraction Reaction mechanisms Rate constants
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Theoretical Study on the Excited-state Intramolecular Hydrogen Abstraction Reactions of Butanal 被引量:1
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作者 吕玲玲 杨声 +2 位作者 袁琨 王小芳 王永成 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第10期1226-1235,共10页
The excited-state intramolecular hydrogen abstraction reactions of butanal have been investigated using the CAS-MP2/6-311+G^*//CASSCF/6-31G^* methods. Calculated results show that the hydrogen transfer induced fluo... The excited-state intramolecular hydrogen abstraction reactions of butanal have been investigated using the CAS-MP2/6-311+G^*//CASSCF/6-31G^* methods. Calculated results show that the hydrogen transfer induced fluorescence quenching of the n,π^*-excited state of covalent butanal with three paths: (1) The first path corresponds to direct S0-react reconstitution, which involves the first S1 decay by partial hydrogen atom transfer. (2) The second stepwise mechanism can be viewed as a full hydrogen atom transfer followed by a partial hydrogen atom back transfer, electron transfer (near S1/S0 or S0-TS) and finally a proton transfer to S0-react. (3) On the triplet surface, the surface crossing to the singlet state would be clearly much efficient at the T1/S0 region due to the large SOC value of 8.3 cm^-1. The S0-react decay route from T1/S0 was studied with an intrinsic reaction coordinate (IRC) calculation at the CASSCF level, resulting in the S0-React minimum. 展开更多
关键词 butanal valence bond theory (VB) state correlation diagram hydrogen abstraction mechanism
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Topology Abstraction Service for IP VPNs: Core Network Partitioning for Resource Sharing 被引量:1
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作者 Ravishankar Ravindran Changcheng Huang +1 位作者 Krishnaiyan Thulasiraman Tachun Lin 《American Journal of Operations Research》 2018年第3期167-202,共36页
VPN service providers (VSP) and IP-VPN customers have traditionally maintained service demarcation boundaries between their routing and signaling entities. This has resulted in the VPNs viewing the VSP network as an o... VPN service providers (VSP) and IP-VPN customers have traditionally maintained service demarcation boundaries between their routing and signaling entities. This has resulted in the VPNs viewing the VSP network as an opaque entity and therefore limiting any meaningful interaction between the VSP and the VPNs. A key challenge is to expose each VPN to information about available network resources through an abstraction (TA) [1] which is both accurate and fair. In [2] we proposed three decentralized schemes assuming that all the border nodes performing the abstraction have access to the entire core network topology. This assumption likely leads to over- or under-subscription. In this paper we develop centralized schemes to partition the core network capacities, and assign each partition to a specific VPN for applying the decentralized abstraction schemes presented in [2]. First, we present two schemes based on the maximum concurrent flow and the maximum multicommodity flow (MMCF) formulations. We then propose approaches to address the fairness concerns that arise when MMCF formulation is used. We present results based on extensive simulations on several topologies, and provide a comparative evaluation of the different schemes in terms of abstraction efficiency, fairness to VPNs and call performance characteristics achieved. 展开更多
关键词 IP-VPN SERVICE TOPOLOGY abstraction MAXIMUM Concurrent FLOW MAXIMUM MULTICOMMODITY FLOW
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Research on the Automatic Pattem Abstraction and Recognition Methodology for Large-scale Database System based on Natural Language Processing 被引量:1
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作者 RongWang Cuizhen Jiao Wenhua Dai 《International Journal of Technology Management》 2015年第9期125-127,共3页
In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connec... In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connection between nodes, data across different nodes and even regional distribution are well recognized. In order to reduce data redundancy and model design of the database will usually contain a lot of forms we combine the NLP theory to optimize the traditional method. The experimental analysis and simulation proves the correctness of our method. 展开更多
关键词 Pattern abstraction and Recognition Database System Natural Language Processing.
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Vibration Feature Abstraction and Classification of Diesel Fault 被引量:1
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作者 ZHANG Xi ning, WEN Guang rui, LI Xin yi College of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, P.R.China Abstract: The feature of a periodic cyclic nonstationary signal for a cyclic working machine such as a diesel engine is studied in the aspect of working procedure, force and vibration. On the basis of the study, a method of characteristic 《International Journal of Plant Engineering and Management》 2003年第1期35-40,共6页
ion and classification is put forward for periodic cyclic nonstationary vibration signal. The proposed method is applied to experimental data of an ISUZU C240 diesel engine. Experiment results show the effectiveness ... ion and classification is put forward for periodic cyclic nonstationary vibration signal. The proposed method is applied to experimental data of an ISUZU C240 diesel engine. Experiment results show the effectiveness of the proposed method in classification of engine faults. 展开更多
关键词 diesel engine periodic cyclic nonstationary signal feature abstraction principal component analysis
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Abstraction from Constructors and Functional Constructors and Their Applications
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作者 Kazuhiko Kakehi 1, Robert Gluck 2, Yoshihiko Futamura 3 1 JSPS Research Fellow Graduate School of Science and Engineering, Waseda University,Tokyo 169 8555, Japan 2 PRESTO, JST & Institute for Software Production Technology, Waseda Universi 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期368-374,共7页
Structures using constructors are of ordinary use in functional programming to represent data structures of unbound size. Lack of associativity of constructors, however, hinders program analyses or efficient execution... Structures using constructors are of ordinary use in functional programming to represent data structures of unbound size. Lack of associativity of constructors, however, hinders program analyses or efficient executions. This paper describes ideas of abstraction toward constructors, and similarly abstraction from constructing functions, which we call functional constructors. We demonstrate our ideas making program analyses easier and enable transformation to efficient execution. 展开更多
关键词 program transformation lambda abstraction CONSTRUCTORS recursion removal tupling
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Automatic abstraction of interference fringes with image technique
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作者 浦昭邦 陶卫 张敏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期166-169,共4页
ion technique of interference fringes used in phase modulation and phase scanning modulation interferometer is presented. For the measurement of amplitudes of interference fringes, fringes are fitted and their central... ion technique of interference fringes used in phase modulation and phase scanning modulation interferometer is presented. For the measurement of amplitudes of interference fringes, fringes are fitted and their central points are determined automatically according to their distribution rules. However, for the measurement of their phases, fringes should be recognized and processed with different calculating algorithms and least square optimization methods depending on the scanning modulation mode. When this technique is used for measurement of surface roughness, the measurement uncertainty is better than 5nm and the repeatability is less than 5%. 展开更多
关键词 INTERFERENCE FRINGES abstraction PHASE-MODULATION IMAGE detection
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The CH_3OH+Cl Hydrogen Abstraction Reactions: An ab initio Study
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作者 Bo Zhen CHEN Ming Bao HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第8期727-730,共4页
The two channels of the CH(3)OH+Cl hydrogen abstraction reaction, leading to the final products CH(2)OH+HCl (i) and CH(3)O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-va... The two channels of the CH(3)OH+Cl hydrogen abstraction reaction, leading to the final products CH(2)OH+HCl (i) and CH(3)O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-valence polarization basis sets. For each of the two channels the following simple reaction path is predicted: reactants --> transition state --> intermediate --> products. The previously reported complicated paths(2) calculated without using the IRC technique are criticized. Our calculations indicate that channel (i) is exothermic and has a negligible energy barrier while channel (ii) is endothermic and has a substantial energy barrier. These results imply that channel (i) is favorable, which is in line with experiment. 展开更多
关键词 abstraction reaction ab initio calculation IRC
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Deadlock detection using abstraction refinement
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作者 曾红卫 《Journal of Shanghai University(English Edition)》 2010年第1期1-5,共5页
This paper adopts counterexample guided abstraction refinement scheme to alleviate the state explosion problem of deadlock detection. We extend the classical labeled transition system models by qualifying transitions ... This paper adopts counterexample guided abstraction refinement scheme to alleviate the state explosion problem of deadlock detection. We extend the classical labeled transition system models by qualifying transitions as certain and uncertain to make deadlock-freedom conservative, i.e. if the abstraction of a system is deadlock-free, then the system is deadlock-free. An abstraction refinement approach to deadlock detection is proposed, and the correctness of the approach is proved. 展开更多
关键词 deadlock detection state explosion extended labeled transition system abstraction refinement COUNTEREXAMPLE
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Modeling Abstraction Hierarchy Levels of the Cyber Attacks Using Random Process
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作者 Gilles Durrieu Emmanuel Frenod +1 位作者 Thierry Morineau Thong Quoc Nguyen 《Open Journal of Statistics》 2017年第3期500-520,共21页
Aspects of human behavior in cyber security allow more natural security to the user. This research focuses the appearance of anticipating cyber threats and their abstraction hierarchy levels on the mental picture leve... Aspects of human behavior in cyber security allow more natural security to the user. This research focuses the appearance of anticipating cyber threats and their abstraction hierarchy levels on the mental picture levels of human. The study concerns the modeling of the behaviors of mental states of an individual under cyber attacks. The mental state of agents being not observable, we propose a non-stationary hidden Markov chain approach to model the agent mental behaviors. A renewal process based on a nonparametric estimation is also considered to investigate the spending time in a given mental state. In these approaches, the effects of the complexity of the cyber attacks are taken into account in the models. 展开更多
关键词 CYBER ATTACKS abstraction HIERARCHY Hidden Markov Chain NONPARAMETRIC Estimation RENEWAL Process
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Density Functional Theory Studies on the Addition and Abstraction Reactions of OH Radical with Benzoate Anion
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作者 Nobuaki Tanaka Shigeo Itoh 《Open Journal of Physical Chemistry》 2013年第1期7-13,共7页
The addition and abstraction reactions of OH radical with benzoate anion are investigated by density functional theory calculations that include solvent effects using UB3LYP, UCAM-B3LYP, UmPW1PW91 and UM06-2X function... The addition and abstraction reactions of OH radical with benzoate anion are investigated by density functional theory calculations that include solvent effects using UB3LYP, UCAM-B3LYP, UmPW1PW91 and UM06-2X functionals with the 6-311++G(2d,2p) basis set. Geometry optimizations of the reactants, products and transition state species are performed for the possible reaction paths. For the addition reactions, those targeting the ipso-, ortho-, meta- and para-carbons are predicted to be exoergic. The H-atom abstraction reactions from ortho, meta and para positions are also predicted to be exoergic. On the basis of the rate constants calculated by means of the transition state theory, the H-atom abstraction reaction from the ortho position is determined to be the favored path followed by the ortho OH addition reaction. 展开更多
关键词 DFT Calculation BENZOATE ANION H-ATOM abstraction OH ADDITION Transition State Theory
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Real-time flow-based video abstraction using OpenCL
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作者 Yong-jin PARK Jin-woo KIM +1 位作者 Jin-hong PARK Tack-don HAN 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期46-50,共5页
A non-photorealistic rendering technique is a method to show various effects different from those of realistic image generation.Of the various techniques,flow-based image abstraction displays the shape and color featu... A non-photorealistic rendering technique is a method to show various effects different from those of realistic image generation.Of the various techniques,flow-based image abstraction displays the shape and color features well and performs a stylistic visual abstraction.But real-time rendering is impossible when CPU is used because it applies various filtering and iteration methods.In this paper,we present real-time processing methods of video abstraction using open open computing language(OpenCL),technique of general-purpose computing on graphics processing units(GPGPU).Through the acceleration of general-purpose computing(GPU),16 frame-per-second(FPS)or greater is shown to process video abstraction. 展开更多
关键词 non-photorealistic rendering video abstraction general-purpose computing on graphics processing units(GPGPU) open computing language(OpenCL)
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Multiple Levels of Abstraction in the Simulation of Microthreaded Many-Core Architectures
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作者 Irfan Uddin 《Open Journal of Modelling and Simulation》 2015年第4期159-190,共32页
Simulators are generally used during the design of computer architectures. Typically, different simulators with different levels of complexity, speed and accuracy are used. However, for early design space exploration,... Simulators are generally used during the design of computer architectures. Typically, different simulators with different levels of complexity, speed and accuracy are used. However, for early design space exploration, simulators with less complexity, high simulation speed and reasonable accuracy are desired. It is also required that these simulators have a short development time and that changes in the design require less effort in the implementation in order to perform experiments and see the effects of changes in the design. These simulators are termed high-level simulators in the context of computer architecture. In this paper, we present multiple levels of abstractions in a high-level simulation of a general-purpose many-core system, where the objective of every level is to improve the accuracy in simulation without significantly affecting the complexity and simulation speed. 展开更多
关键词 HIGH-LEVEL Simulations MULTIPLE LEVELS of abstraction Design Space Exploration MANY-CORE Systems
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Internal Water Flows and Particles Abstraction in Daphnia
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作者 Moshe Gophen 《Open Journal of Ecology》 2022年第11期742-755,共14页
The operational function of the trunk limbs (thoracic appendages), of Daphnia, P3 and P4, is a long-term disputed definition between “solid walls”, sieving filters. Sieving is unlikely process for routine particle c... The operational function of the trunk limbs (thoracic appendages), of Daphnia, P3 and P4, is a long-term disputed definition between “solid walls”, sieving filters. Sieving is unlikely process for routine particle collection, particle capture is not a simple mechanical process and not by sieving alone. Analysis promotion supported by direct observational examination of the in-vivo cinematographic slow-motion film and magnified solid photos of tethered Daphnia by high-speed camera (250 frames per second) resulted in a definite interpretation presented in this paper. The Daphnia’s feeding mechanism achieves particles abstraction not by sieving. The existence of two internal alternate water flow routs was indicated: Lateral and Median. These micro flow structures are suggested as vulnerability reduction. 展开更多
关键词 DAPHNIA Particle abstraction Solid Walls Internal Flow Rout
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Visual abstraction of dynamic network via improved multi-class blue noise sampling
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作者 Yanni PENG Xiaoping FAN +5 位作者 Rong CHEN Ziyao YU Shi LIU Yunpeng CHEN Ying ZHAO Fangfang ZHOU 《Frontiers of Computer Science》 SCIE EI CSCD 2023年第1期171-185,共15页
Massive sequence view (MSV) is a classic timeline-based dynamic network visualization approach. However, it is vulnerable to visual clutter caused by overlapping edges, thereby leading to unexpected misunderstanding o... Massive sequence view (MSV) is a classic timeline-based dynamic network visualization approach. However, it is vulnerable to visual clutter caused by overlapping edges, thereby leading to unexpected misunderstanding of time-varying trends of network communications. This study presents a new edge sampling algorithm called edge-based multi-class blue noise (E-MCBN) to reduce visual clutter in MSV. Our main idea is inspired by the multi-class blue noise (MCBN) sampling algorithm, commonly used in multi-class scatterplot decluttering. First, we take a node pair as an edge class, which can be regarded as an analogy to classes in multi-class scatterplots. Second, we propose two indicators, namely, class overlap and inter-class conflict degrees, to measure the overlapping degree and mutual exclusion, respectively, between edge classes. These indicators help construct the foundation of migrating the MCBN sampling from multi-class scatterplots to dynamic network samplings. Finally, we propose three strategies to accelerate MCBN sampling and a partitioning strategy to preserve local high-density edges in the MSV. The result shows that our approach can effectively reduce visual clutters and improve the readability of MSV. Moreover, our approach can also overcome the disadvantages of the MCBN sampling (i.e., long-running and failure to preserve local high-density communication areas in MSV). This study is the first that introduces MCBN sampling into a dynamic network sampling. 展开更多
关键词 dynamic network visualization massive sequence view multi-class blue noise sampling visual abstraction
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Intelligent Transformation: General Intelligence Theory
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作者 Alexander Ngu Amaya Odilon Kosso 《International Journal of Intelligence Science》 2024年第3期59-70,共12页
This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the c... This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the concept of equality = limits the sensitivity of our mathematics to abstract relationships. We propose a new relation principle that does not rely on the concept of equality but is consistent with existing mathematical abstractions. In essence, this paper proposes a conceptual framework for general interaction and argues that this framework is also an abstraction that satisfies the definition of Intelligence. Hence, we define intelligence as a formalization of generality, represented by the abstraction ∆∞Ο, where each symbol represents the concepts infinitesimal, infinite, and finite respectively. In essence, this paper proposes a General Language Model (GLM), where the abstraction ∆∞Ο represents the foundational relationship of the model. This relation is colloquially termed “The theory of everything”. 展开更多
关键词 INTELLIGENCE GENERALIZATION abstraction TRANSFORMATION General Language Model General Intelligence Theory Theory of Everything
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Unified Enclave Abstraction and Secure Enclave Migration on Heterogeneous Security Architectures 被引量:3
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作者 Jin-Yu Gu Hao Li +3 位作者 Yu-Bin Xia Hai-Bo Chen Cheng-Gang Qin Zheng-Yu He 《Journal of Computer Science & Technology》 SCIE EI CSCD 2022年第2期468-486,共19页
ion and secure enclave migration on heterogeneous security architectures.
关键词 heterogeneous trusted execution environment(TEE) enclave abstraction enclave migration
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