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Information Conductivity:Universal Performance Measure for Semantic Communications
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作者 Liang Zijian Niu Kai Zhang Ping 《China Communications》 SCIE CSCD 2024年第7期17-36,共20页
As a novel paradigm,semantic communication provides an effective solution for breaking through the future development dilemma of classical communication systems.However,it remains an unsolved problem of how to measure... As a novel paradigm,semantic communication provides an effective solution for breaking through the future development dilemma of classical communication systems.However,it remains an unsolved problem of how to measure the information transmission capability for a given semantic communication method and subsequently compare it with the classical communication method.In this paper,we first present a review of the semantic communication system,including its system model and the two typical coding and transmission methods for its implementations.To address the unsolved issue of the information transmission capability measure for semantic communication methods,we propose a new universal performance measure called Information Conductivity.We provide the definition and the physical significance to state its effectiveness in representing the information transmission capabilities of the semantic communication systems and present elaborations including its measure methods,degrees of freedom,and progressive analysis.Experimental results in image transmission scenarios validate its practical applicability. 展开更多
关键词 information conductivity information transmission capability semantic communications system model universal performance measure
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A deformation measurement method based on surface texture information of rocks and its application
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作者 Yanbo Zhang Xin Han +4 位作者 Peng Liang Xulong Yao Qun Li Guangyuan Yu Qi Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第9期1117-1130,共14页
Users of the digital image correlation method are faced with the problem of poor operability,low repeatability,and lack of standardized specifications for spraying speckles.To solve the problem,the research proposed a... Users of the digital image correlation method are faced with the problem of poor operability,low repeatability,and lack of standardized specifications for spraying speckles.To solve the problem,the research proposed a rock deformation measurement method that obviates the need to spray speckles.A local binary model was established by using the local binary pattern(LBP)operator based on deep texture features on rock surfaces.The resulting LBP digital speckle pattern can substitute artificial speckle patterns and demonstrates high quality and strong applicability.Based on the LBP digital speckle pattern,the target tracking algorithm was employed to achieve non-contact measurement of the dynamic displacements of rocks.The feasibility and effectiveness of the algorithm in practical application were verified by conducting shear tests on granite and siltstone.Test results show that the deformation characteristics in the displacement nephograms are in line with the measured data pertaining to rock fracturing and conform to the basic characteristics of the shear failure of rocks.The deformation measurement method based on surface texture information can realize non-contact displacement measurement of rocks under conditions without speckles:this obviates the influence of the quality of sprayed speckles on the accuracy of the measurement of deformation. 展开更多
关键词 Deformation measurement Texture information Digital speckle Local binary model Target tracking algorithm
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Information Security in the Cloud: Emerging Trends and Challenges
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作者 Keerthana Chitreddy Andrew Mikhl Anthony +1 位作者 Chinna Manikanta Bandaru Olatunde Abiona 《International Journal of Communications, Network and System Sciences》 2024年第5期69-80,共12页
This article explores the evolution of cloud computing, its advantages over traditional on-premises infrastructure, and its impact on information security. The study presents a comprehensive literature review covering... This article explores the evolution of cloud computing, its advantages over traditional on-premises infrastructure, and its impact on information security. The study presents a comprehensive literature review covering various cloud infrastructure offerings and security models. Additionally, it deeply analyzes real-life case studies illustrating successful cloud migrations and highlights common information security threats in current cloud computing. The article concludes by offering recommendations to businesses to protect themselves from cloud data breaches and providing insights into selecting a suitable cloud services provider from an information security perspective. 展开更多
关键词 Cloud Computing information Security Cloud Infrastructure Offerings Cloud Migration Security measures Data Breaches Cloud Service Providers CYBERSECURITY Cloud Security Case Studies Cloud Threat Landscape Data Encryption COMPLIANCE Cloud Security Tools
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite information Quantity Formulating a Model measurement Accuracy Limit Objective Model Selection
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Integrating unascertained measurement and information entropy theory to assess blastability of rock mass 被引量:15
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作者 周健 李夕兵 《Journal of Central South University》 SCIE EI CAS 2012年第7期1953-1960,共8页
Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual charac... Due to the complex features of rock mass blastability assessment systems, an evaluation model of rock mass blastability was established on the basis of the unascertained measurement (UM) theory and the actual characteristics of the project. Considering a comprehensive range of intact rock properties and discontinuous structures of rock mass, twelve main factors influencing the evaluation blastability of rock mass were taken into account in the UM model, and the blastability evaluation index system of rock mass was constructed. The unascertained evaluation indices corresponding to the selected factors for the actual situation were solved both qualitatively and quantitatively. Then, the UM function of each evaluation index was obtained based on the initial data for the analysis of the blastability of six rock mass at a highway improvement cutting site in North Wales. The index weights of the factors were calculated by entropy theory, and credible degree identification (CDI) criteria were established according to the UM theory. The results of rock mass blastability evaluation were obtained by the CDI criteria. The results show that the UM model assessment results agree well with the actual records, and are consistent with those of the fuzzy sets evaluation method. Meanwhile, the unascertained superiority degree of rock mass blastability of samples S1-$6 which can be calculated by scoring criteria are 3.428 5, 3.453 3, 4.058 7, 3.675 9, 3.516 7 and 3.289 7, respectively. Furthermore, the proposed method can take into account large amount of uncertain information in blastability evaluation, which can provide an effective, credible and feasible way for estimating the blastability of rock mass. Engineering practices show that it can complete the blastability assessment systematically and scientifically without any assumption by the proposed model, which can be applied to practical engineering. 展开更多
关键词 rock mass BLASTABILITY unascertained measurement (UM) model information entropy PREDICTION
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Measurement and Assessment of Physical Activity by Information and Communication Technology 被引量:1
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作者 ZHANG Qun YANG Xi +1 位作者 LIU Dan ZHAO Wen Hua 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第6期465-472,共8页
This study provides explorative insights into the information and communication technology (ICT) for promoting the physical activity level. ICT has provided innovative ideas and perspectives for PA measurement, asse... This study provides explorative insights into the information and communication technology (ICT) for promoting the physical activity level. ICT has provided innovative ideas and perspectives for PA measurement, assessment, evaluation and health intervention. ICT that aims to increase exercise for the entire population should be of a well-oriented and easy-to-use design with the options of tailored and personalized feedback, coaching, and ranking and supporting; it should be capable of setting goals and working with a schedule and be accompanied by a website to provide overviews of the users' exercise results and progress. 展开更多
关键词 Physical activity measureMENT ASSESSMENT information and communicationtechnology
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Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out 被引量:3
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作者 Man Hung Jerry Bounsanga +1 位作者 Maren W Voss Charles L Saltzman 《World Journal of Orthopedics》 2018年第3期41-49,共9页
AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint condition... AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an anchor.RESULTS There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS JR.CONCLUSION This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments. 展开更多
关键词 Hhip DISABILITY and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Patient-Reported OUTCOMES measurement information System Physical Function Knee injury and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Minimum clinically important difference JOINT Physical function Minimum detectable change Arthroplasty Orthopaedics Clinical OUTCOMES
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Information fusion of train speed and distance measurements based on fuzzy adaptive Kalman filter algorithm 被引量:1
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作者 FAN Ze yuan DONG Yu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第3期286-292,共7页
The measurement accuracy of speed and distance in high speed train directly affects the control precision and driving efficiency of train control system. To improve the capability of train self control, a combined spe... The measurement accuracy of speed and distance in high speed train directly affects the control precision and driving efficiency of train control system. To improve the capability of train self control, a combined speed measurement and positioning method based on speed sensor and radar which is assisted by global positioning system(GPS) is proposed to improve the accuracy of measurement and reduce the dependence on the ground equipment. In consideration of the fact that the filtering precision of Kalman filter will decrease when the statistical characteristics are changing, this paper uses fuzzy comprehensive evaluation method to evaluate the sub filter, and information distribution coefficients are dynamically adjusted according to filtering reliability, which can improve the fusion accuracy and fault tolerance of the system. The sub filter is required to carry on the covariance shaping adaptive filtering when it is in the suboptimal state. The adjustment factor of error covariance is obtained according to the minimized cost function, which can improve the matching degree between the measured residual variance and the system recursive residual. The simulation results show that the improved filter algorithm can track the changes of the system effectively, enhance the filtering accuracy significantly, and improve the measurement accuracies of train speed and distance. 展开更多
关键词 information fusion federated Kalman filter fuzzy comprehensive evaluation train speed and distance measurements
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Bidirectional transfer of quantum information for unknown photons via cross-Kerr nonlinearity and photon-number-resolving measurement
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作者 Jino Heo Chang-Ho Hong +1 位作者 Dong-Hoon Lee Hyung-Jin Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期82-92,共11页
We propose an arbitrary controlled-unitary (CU) gate and a bidirectional transfer scheme of quantum information (BTQI) for unknown photons. The proposed CU gate utilizes quantum non-demolition photon-number-resolv... We propose an arbitrary controlled-unitary (CU) gate and a bidirectional transfer scheme of quantum information (BTQI) for unknown photons. The proposed CU gate utilizes quantum non-demolition photon-number-resolving measure- ment based on the weak cross-Kerr nonlinearities (XKNLs) and two quantum bus beams; the proposed CU gate consists of consecutive operations of a controlled-path gate and a gathering-path gate. It is almost deterministic and is feasible with current technology when a strong amplitude of the coherent state and weak XKNLs are employed. Compared with the existing optical multi-qubit or controlled gates, which utilize XKNLs and homodyne detectors, the proposed CU gate can increase experimental realization feasibility and enhance robustness against decoherence. According to the CU gate, we present a BTQI scheme in which the two unknown states of photons between two parties (Alice and Bob) are mutually swapped by transferring only a single photon. Consequently, by using the proposed CU gate, it is possible to experimentally implement the BTQI scheme with a certain probability of success. 展开更多
关键词 cross-Kerr nonlinearity quantum non-demolition photon-number-resolving measurement bidirec-tional transfer of quantum information
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An Entropy Measurement Method of Quantum Information System under Uncertain Environment
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作者 Zijing Li Jiangnan Deng +2 位作者 Bing Zhou Ying Liu Zhengying Cai 《International Journal of Intelligence Science》 2018年第2期29-41,共13页
Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncer... Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncertainty, a quantum uncertain model is proposed to simulate a quantum information system under uncertain environment, and to simplify the entropy measurement of quantum information system. Second, different from the classic random seed under uncertain environment which is often called as pseudo-random number, here the quantum random is employed to provide us a true random model for the entropy of quantum information system. Third, the complex interaction and entangling activity of uncertain factors of quantum information is modeled as quantum binary instead of classic binary, which can help us to evaluate the entropy of uncertain environment, to analyze the entropy divergence in quantum information system. This work presents a non-classic risk factor measurement for quantum information system and a helpful entropy measurement. 展开更多
关键词 ENTROPY measurement Method QUANTUM information System UNCERTAIN ENVIRONMENT QUANTUM ENCRYPTION
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The matrix representation for the mathematic structure of Shannon’s information measures
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作者 苑延华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期232-235,共4页
Shannon’s information measure is a crucial concept in Information Theory. And the research, for the mathematics structure of Shannon’s information measure, is to recognize the essence of information measure. The lin... Shannon’s information measure is a crucial concept in Information Theory. And the research, for the mathematics structure of Shannon’s information measure, is to recognize the essence of information measure. The linear relation between Shannon’s information measures and some signed measure space by using the formal symbols substitution rule is discussed. Furthermore, the coefficient matrix recurrent formula of the linear relation is obtained. Then the coefficient matrix is proved to be invertible via mathematical induction. This shows that the linear relation is one-to-one, and according to this, it can be concluded that a compact space can be generated from Shannon’s information measures. 展开更多
关键词 ENTROPY Shannon's information measures signed measure the recurrent formula of l-measure matrix
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INFORMATION FUSION STEADY-STATE WHITE NOISE DECONVOLUTION ESTIMATORS WITH TIME-DELAYED MEASUREMENTS AND COLORED MEASUREMENT NOISES
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作者 Sun Xiaojun Deng Zili 《Journal of Electronics(China)》 2009年第2期161-167,共7页
White noise deconvolution or input white noise estimation problem has important appli-cation backgrounds in oil seismic exploration,communication and signal processing.By the modern time series analysis method,based o... White noise deconvolution or input white noise estimation problem has important appli-cation backgrounds in oil seismic exploration,communication and signal processing.By the modern time series analysis method,based on the Auto-Regressive Moving Average(ARMA) innovation model,under the linear minimum variance optimal fusion rules,three optimal weighted fusion white noise deconvolution estimators are presented for the multisensor systems with time-delayed measurements and colored measurement noises.They can handle the input white noise fused filtering,prediction and smoothing problems.The accuracy of the fusers is higher than that of each local white noise estimator.In order to compute the optimal weights,the formula of computing the local estimation error cross-covariances is given.A Monte Carlo simulation example for the system with 3 sensors and the Bernoulli-Gaussian input white noise shows their effectiveness and performances. 展开更多
关键词 Multisensor information fusion White noise estimator DECONVOLUTION Time-delayed measurement Modern time series analysis method
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Information-theoretic Measures for Objective Evaluation of Classifications 被引量:1
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作者 HU Bao-Gang HE Ran YUAN Xiao-Tong 《自动化学报》 EI CSCD 北大核心 2012年第7期1169-1182,共14页
关键词 评价技术 信息论 分类 ITMS 错误类型 性能指标 离子阱质谱 信息理论
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Application of Wireless Network Positioning Technology Based on GPS in Geographic Information Measurement
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作者 Yaping Mao Kaiyong Li Duolu Mao 《Journal of New Media》 2020年第3期131-135,共5页
Based on the analysis of the advantages and disadvantages of GPS positioning system in practical application,this paper proposes the combination of wireless network positioning technology and GPS positioning system to... Based on the analysis of the advantages and disadvantages of GPS positioning system in practical application,this paper proposes the combination of wireless network positioning technology and GPS positioning system to overcome the low accuracy of GPS positioning system in the case of occlusion.This paper introduces in detail the principle of the application of wireless network positioning technology based on GPS positioning system in geographic information measurement,and illustrates its practical application in production by taking coal mine positioning as an example. 展开更多
关键词 GPS network location geographic information measurement
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Shannon Entropy as a Measurement of the Information in a Multiconfiguration Dirac-Fock Wavefunction
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作者 万建杰 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期52-55,共4页
Discrete Shannon entropy is applied to describe the information in a multiconfiguration Dirac Fock wavefunction. The dependence of Shannon entropy is shown as enlarging the configuration space and it can reach saturat... Discrete Shannon entropy is applied to describe the information in a multiconfiguration Dirac Fock wavefunction. The dependence of Shannon entropy is shown as enlarging the configuration space and it can reach saturation when there are enough configuration state wavefunctions to obtain the convergent energy levels; that is, the calculation procedure in multiconfiguration Dirae Fock method is an entropy saturation process. At the same accuracy level, the basis sets for the smallest entropy are best able to describe the energy state. Additionally, a connection between the sudden change of Shannon information entropies and energy level crossings along with isoelectronic sequence can be set up, which is helpful to find the energy level crossings of interest in interpreting and foreseeing the inversion scheme of energy levels for an x-ray laser. 展开更多
关键词 Shannon Entropy as a measurement of the information in a Multiconfiguration Dirac-Fock Wavefunction
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Six Measures to Help SMEs out——An Interview with the Vice Minister of Industry and Information Technology
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《China's Foreign Trade》 2008年第Z3期36-37,共2页
With the global economic turmoil and the changes in Chinese economic pol- icies in 2008,small,and medium-sized enterprises(SMEs)have all felt the early-coming of a"cold season".They have been undergoing extr... With the global economic turmoil and the changes in Chinese economic pol- icies in 2008,small,and medium-sized enterprises(SMEs)have all felt the early-coming of a"cold season".They have been undergoing extreme dif- ficulties in doing businesses due to a series of factors including 展开更多
关键词 HELP An Interview with the Vice Minister of Industry and information Technology Six measures to Help SMEs out
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In-situ multi-information measurement system for preparing gallium nitride photocathode
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作者 付小倩 常本康 +1 位作者 钱芸生 张俊举 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期1-4,共4页
We introduce the first domestic in-situ multi-information measurement system for a gallium nitride (GaN) photo- cathode. This system can successfully fulfill heat cleaning and activation for GaN in an ultrahigh vacu... We introduce the first domestic in-situ multi-information measurement system for a gallium nitride (GaN) photo- cathode. This system can successfully fulfill heat cleaning and activation for GaN in an ultrahigh vacuum environment and produce a GaN photocathode with a negative electron affinity (NEA) status. Information including the heat clean- ing temperature, vacuum degree, photocurrent, electric current of cesium source, oxygen source, and the most important information about the spectral response, or equivalently, the quantum efficiency (QE) can be obtained during prepa- ration. The preparation of a GaN photocathode with this system indicates that the optimal heating temperature in a vacuum is about 700 ~C. We also develop a method of quickly evaluating the atomically clean surface with the vacuum degree versus wavelength curve to prevent possible secondary contamination when the atomic level cleaning surface is tested with X-ray photoelectron spectroscopy. The photocurrent shows a quick enhancement when the current ratio between the cesium source and oxygen source is 1.025. The spectral response of the GaN photocathode is flat in a wavelength range from 240 nm to 365 nm, and an abrupt decline is observed at 365 nm, which demonstrates that with the in-si$u multi-information measurement system the NEA GaN photocathode can be successfully prepared. 展开更多
关键词 gallium nitride PHOTOCATHODE in-situ multi-information measurement
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Discussion about similarity measures in pattern recognition of fuzzy information
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作者 GUO Zhang-lin TIAN Jing 《通讯和计算机(中英文版)》 2008年第6期10-15,共6页
关键词 相似形 测量方法 信息技术 模糊理论
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Bounds for the Generalized Entropy-Type Information Measure
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作者 Christos Kitsos Thomas Toulias 《通讯和计算机(中英文版)》 2012年第1期56-64,共9页
关键词 信息测度 广义熵 不确定性 高斯 估计
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Foundations and Applications of Information Systems Dynamics
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作者 Jianfeng Xu Zhenyu Liu +4 位作者 Shuliang Wang Tao Zheng Yashi Wang Yingfei Wang Yingxu Dang 《Engineering》 SCIE EI CAS CSCD 2023年第8期254-265,共12页
Although numerous advances have been made in information technology in the past decades,there is still a lack of progress in information systems dynamics(ISD),owing to the lack of a mathematical foundation needed to d... Although numerous advances have been made in information technology in the past decades,there is still a lack of progress in information systems dynamics(ISD),owing to the lack of a mathematical foundation needed to describe information and the lack of an analytical framework to evaluate information systems.The value of ISD lies in its ability to guide the design,development,application,and evaluation of largescale information system-of-systems(So Ss),just as mechanical dynamics theories guide mechanical systems engineering.This paper reports on a breakthrough in these fundamental challenges by proposing a framework for information space,improving a mathematical theory for information measurement,and proposing a dynamic configuration model for information systems.In this way,it establishes a basic theoretical framework for ISD.The proposed theoretical methodologies have been successfully applied and verified in the Smart Court So Ss Engineering Project of China and have achieved significant improvements in the quality and efficiency of Chinese court informatization.The proposed ISD provides an innovative paradigm for the analysis,design,development,and evaluation of large-scale complex information systems,such as electronic government and smart cities. 展开更多
关键词 System-of-systems engineering information theory information measurement information systems dynamics Judicial informatization
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