期刊文献+
共找到112篇文章
< 1 2 6 >
每页显示 20 50 100
ON INFORMATION THEORY METHOD FOR RELIABILITY ASSESSMENT OF SYSTEMS CONSISTING OF DIFFERENT SUCCESS FAILURE MODEL UNITS 被引量:1
1
作者 孙有朝 施军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期129-133,共5页
Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synt... Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models. 展开更多
关键词 information theory information quantity success failure model units reliability assessment approximate lower limit
下载PDF
Agriculture Information Retrieval System Based on Comprehensive Information Theory 被引量:7
2
作者 吴启明 《Agricultural Science & Technology》 CAS 2010年第2期143-145,共3页
Through analyzing syntactic,semantic,pragmatic information,the retrieval system ACIS based on comprehensive information was established,which could achieve personalized information exaction to guide user s information... Through analyzing syntactic,semantic,pragmatic information,the retrieval system ACIS based on comprehensive information was established,which could achieve personalized information exaction to guide user s information retrieval. 展开更多
关键词 Comprehensive information theory AGRICULTURE information retrieval system
下载PDF
Information Theory of Cartography:An Information-theoretic Framework for Cartographic Communication 被引量:12
3
作者 Zhilin LI Peichao GAO Zhu XU 《Journal of Geodesy and Geoinformation Science》 2021年第1期1-16,共16页
Map is one of the communication means created by human being.Cartographers have been making efforts on the comparison of maps to natural languages so as to establish a"cartographic language"or"map langu... Map is one of the communication means created by human being.Cartographers have been making efforts on the comparison of maps to natural languages so as to establish a"cartographic language"or"map language".One of such efforts is to adopt the Shannon’s Information Theory originated in digital communication into cartography so as to establish an entropy-based cartographic communication theory.However,success has been very limited although research work had started as early as the mid-1960 s.It is then found that the bottleneck problem was the lack of appropriate measures for the spatial(configurational)information of(graphic and image)maps,as the classic Shannon entropy is only capable of characterizing statistical information but fails to capture the configurational information of(graphic and image)maps.Fortunately,after over 40-year development,some bottleneck problems have been solved.More precisely,generalized Shannon entropies for metric and thematic information of(graphic)maps have been developed and the first feasible solution for computing the Boltzmann entropy of image maps has been invented,which is capable of measuring the spatial information of not only numerical images but also categorical maps.With such progress,it is now feasible to build the"Information Theory of Cartography".In this paper,a framework for such a theory is proposed and some key issues are identified.For these issues,some have already been tackled while others still need efforts.As a result,a research agenda is set for future action.After all these issues are tackled,the theory will become matured so as to become a theoretic basis of cartography.It is expected that the Information Theory of Cartography will play an increasingly important role in the discipline of cartography because more and more researchers have advocated that information is more fundamental than matter and energy. 展开更多
关键词 information theory of Cartography cartographic communication spatial information of maps generalized Shannon Entropy Boltzmann entropy
下载PDF
Information Theory Model for Radiation
4
作者 Philipp Kornreich 《Journal of Applied Mathematics and Physics》 2016年第8期1610-1616,共7页
Information based models for radiation emitted by a Black Body which passes through a scattering medium are analyzed. In the limit, when there is no scattering this model reverts to the Black Body Radiation Law. The a... Information based models for radiation emitted by a Black Body which passes through a scattering medium are analyzed. In the limit, when there is no scattering this model reverts to the Black Body Radiation Law. The advantage of this mathematical model is that it includes the effect of the scattering of the radiation between source and detector. In the case when the exact form of the scattering mechanism is not known a model using a single scattering parameter is derived. A simple version of this model is derived which is useful for analyzing large data. 展开更多
关键词 information theory Maximum information ENTROPY SCATTERING Conditional Entropy
下载PDF
An Information Theory for the Geotechnical Engineering Inverse Problem
5
《岩石力学与工程学报》 EI CAS CSCD 1995年第S1期473-483,共11页
AnInformationTheoryfortheGeotechnicalEngineeringInverseProblemByLiuWeining(DepartmentofCivilEngineering,Nort... AnInformationTheoryfortheGeotechnicalEngineeringInverseProblemByLiuWeining(DepartmentofCivilEngineering,NorthJiaotongUniversi... 展开更多
关键词 An information theory for the Geotechnical Engineering Inverse Problem
下载PDF
Portfolio Diversification Using Information Theory Applied to Brazilian Stocks
6
作者 Hellinton Hatsuo Takada Raphael Assad Santos 《Journal of Mathematics and System Science》 2014年第5期289-294,共6页
Using the concepts from information theory, it is possible to improve the traditional methodologies of asset allocation. In this paper, it was studied and extended the two existent approaches: the first is based on t... Using the concepts from information theory, it is possible to improve the traditional methodologies of asset allocation. In this paper, it was studied and extended the two existent approaches: the first is based on the Shannon entropy concept and the second on the Kullback-Leibler distance. In modem portfolio theory, the investor has two basic procedures: the choice of a portfolio that maximizes its risk-adjusted excess return or the mixed allocation between the maximum Sharpe portfolio and the risk-free asset. The first procedure was already addressed in the related literature. One important contribution of this paper is the consideration of the second procedure in the information theory context. The performance of these approaches was compared with the three traditional asset allocation methodologies: the Markowitz's mean-variance, the resampled mean-variance and the equally weighted portfolio. It was used simulated and real data from Brazilian stocks. The information theory-based methodologies were verified to be more robust when dealing with the estimation errors. 展开更多
关键词 information theory ENTROPY financial markets.
下载PDF
Classical information theory in quantum notations 被引量:1
7
作者 LI Gang YE MingYong LIN XiuMin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第12期2202-2207,共6页
Shannon's noisy channel coding theorem is a cornerstone in the history of classical information theory. A proof of Shannon's noisy channel coding theorem using quantum notations is presented, which sets up a b... Shannon's noisy channel coding theorem is a cornerstone in the history of classical information theory. A proof of Shannon's noisy channel coding theorem using quantum notations is presented, which sets up a bridge between classical information theory and the developing quantum information theory. 展开更多
关键词 quantum channel information theory capacity
原文传递
An Information Theory Approach to the Data Compression and Imaging System for Synthetic Aperture Radar (SAR)
8
作者 Xiao Yongxin Peng Hailiang and Chen Zongzhi(Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, P. R. China.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第1期1-15,共15页
Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its ... Synthetic aperture radar (SAR) is portrayed as a multiple access channel. An information theory approach is applied to the SAR imaging system, and the information content about a target that can be extracted from its radar image is evaluated by the average mutual information measure. A conditional (transition) probability density function (PDF) of the SAR imaging system is derived by analyzing the system and a closed form of the information content is found. It is shown that the information content obtained by the SAR imaging system from an independent sample of echoes will decrease and the total information content obtained by the SAR imaging system will increase with an increase in the number of looks. Because the total average mutual information is also used to define a measure of radiometric resolution for radar images, it is shown that the radiometric resolution of a radar image of terrain will be improved by spatial averaging. In addition, the imaging process and the data compression process for SAR are each treated as an independent generalized communication channel. The effects of data compression upon radiometric resolution for SAR are studied and some conclusions are obtained. 展开更多
关键词 Synthetic aperture radar (SAR) information theory data compression radiometric resolution probability density function (PDF) multiple access channel average mutual information
下载PDF
An information theory perspective on computational vision
9
作者 Alan YUILLE 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2010年第3期329-346,共18页
This paper introduces computer vision from an information theory perspective.We discuss how vision can be thought of as a decoding problem where the goal is to find the most efficient encoding of the visual scene.This... This paper introduces computer vision from an information theory perspective.We discuss how vision can be thought of as a decoding problem where the goal is to find the most efficient encoding of the visual scene.This requires probabilistic models which are capable of capturing the complexity and ambiguities of natural images.We start by describing classic Markov Random Field(MRF)models of images.We stress the importance of having efficient inference and learning algorithms for these models and emphasize those approaches which use concepts from information theory.Next we introduce more powerful image models that have recently been developed and which are better able to deal with the complexities of natural images.These models use stochastic grammars and hierarchical representations.They are trained using images from increasingly large databases.Finally,we described how techniques from information theory can be used to analyze vision models and measure the effectiveness of different visual cues. 展开更多
关键词 computer vision pattern recognition information theory minimum description length Markov random field(MRF)model stochastic grammars
原文传递
Power optimization for multiple QoS,delay,and BER classes relying on nite-delay information theory
10
作者 Chen Gong Qian Gao +1 位作者 Lajos Hanzo Zhengyuan Xu 《Journal of Communications and Information Networks》 2017年第1期33-40,共8页
Future communication systems will include di erent types of messages requiring di erent transmission rates,packet lengths,and service qualities.We address the power-optimization issues of communication systems conveyi... Future communication systems will include di erent types of messages requiring di erent transmission rates,packet lengths,and service qualities.We address the power-optimization issues of communication systems conveying multiple message types based on nite-delay information theory.Given both the normalized transmission rate and the packet length of a system,the actual residual decoding error rate is a function of the transmission power.We propose a generalized power allocation framework for multiple message types.Two di erent optimization cost functions are adopted:the number of service-quality violations encountered and the sum log ratio of the residual decoding error rate.We provide the optimal analytical solution for the former cost function and a heuristic solution based on a genetic algorithm for the latter one.Finally,the performance of the proposed solutions are evaluated numerically. 展开更多
关键词 5G communication short packet ultra-dense delay-limited nite-length information theory power optimization
原文传递
Data Component:An Innovative Framework for Information Value Metrics in the Digital Economy
11
作者 Tao Xiaoming Wang Yu +5 位作者 Peng Jieyang Zhao Yuelin Wang Yue Wang Youzheng Hu Chengsheng Lu Zhipeng 《China Communications》 SCIE CSCD 2024年第5期17-35,共19页
The increasing dependence on data highlights the need for a detailed understanding of its behavior,encompassing the challenges involved in processing and evaluating it.However,current research lacks a comprehensive st... The increasing dependence on data highlights the need for a detailed understanding of its behavior,encompassing the challenges involved in processing and evaluating it.However,current research lacks a comprehensive structure for measuring the worth of data elements,hindering effective navigation of the changing digital environment.This paper aims to fill this research gap by introducing the innovative concept of“data components.”It proposes a graphtheoretic representation model that presents a clear mathematical definition and demonstrates the superiority of data components over traditional processing methods.Additionally,the paper introduces an information measurement model that provides a way to calculate the information entropy of data components and establish their increased informational value.The paper also assesses the value of information,suggesting a pricing mechanism based on its significance.In conclusion,this paper establishes a robust framework for understanding and quantifying the value of implicit information in data,laying the groundwork for future research and practical applications. 展开更多
关键词 data component data element data governance data science information theory
下载PDF
An Exploration on the Theory of Information Economy 被引量:1
12
作者 Zhang Li Liang Jianwu Zhang Li is Deputy Director at Division for World Information Studies, CICIR. Liang Jianwu is Assistant Research Fellow at Division for World Economics Studies, CICIR. 《Contemporary International Relations》 2002年第8期21-40,共20页
Since the 1970s, the application of information processing and information technology has gradually played a dominant role in Western economy, especially in American economy. Since the mid1980s, investment of the Unit... Since the 1970s, the application of information processing and information technology has gradually played a dominant role in Western economy, especially in American economy. Since the mid1980s, investment of the United States, Europe and Japan in information technology has increased drastically, making information 展开更多
关键词 An Exploration on the theory of information Economy
下载PDF
Rural Planning Based on Landscape Information Chain Theory: A Case Study of Jiabi Village in Maoba County, Lichuan City
13
作者 ZHANG Chunlin LI Yao 《Journal of Landscape Research》 2018年第1期21-24,共4页
As the most important part of the construction of beautiful countryside, village planning plays a crucial role in the construction of beautiful countryside. How to construct a beautiful village with prominent regional... As the most important part of the construction of beautiful countryside, village planning plays a crucial role in the construction of beautiful countryside. How to construct a beautiful village with prominent regional characteristics in line with rural natural resources and traditional culture turns out be a problem demanding prompt solution in current theoretical research and practical exploration. With the introduction of the landscape information chain theory, Jiabi Village in Maoba Town, Lichuan City was taken for example to create a complete landscape information chain where tea culture dominates and different cultures intermingle by excavating local landscape information elements, creating landscape information places, and constructing landscape information corridor, so as to create a distinctive beautiful vil age in western Hubei and accord with its positioning of "China's tea homestay culture village" and "China's couplet tea village". 展开更多
关键词 Landscape information chain theory Beautiful countryside Planning and design Jiabi Village
下载PDF
Construction and Practice of Online Course Resources Based on Information Processing Theory:Taking“A Bite of Teochew Cuisine,”a Guangdong First-Class Course,as an Example
14
作者 Junsheng Huang 《Journal of Contemporary Educational Research》 2022年第9期36-45,共10页
“Cantonese Cuisine Master”project is an important policy proposed by China to inherit Cantonese Cuisine culture,promote employment,and achieve targeted poverty reduction and rural revitalization.Confronted with the ... “Cantonese Cuisine Master”project is an important policy proposed by China to inherit Cantonese Cuisine culture,promote employment,and achieve targeted poverty reduction and rural revitalization.Confronted with the demands of more diverse education,it is an essential opportunity and task for the education system to consider how to construct high-quality online courses and pursue higher-quality“Cantonese Cuisine Master”projects in line with the new era.This paper,based on the theory of instructional media and information processing theory,will further clarify the demand,dilemma,and developing strategy of online course construction for culinary majors,and explore its construction and practice with the example of“A Bite of Teochew Cuisine,”a Guangdong first-class course. 展开更多
关键词 Cantonese Cuisine Master Culinary majors Online course resources information processing theory Construction and practice
下载PDF
Application of Information Processing Theory in Second Language Vocabulary Acquisition
15
作者 Xiaojing Liang 《Journal of Contemporary Educational Research》 2021年第12期109-113,共5页
Vocabulary acquisition is an intricate process,which has a close relationship with memory.In cognitive psychology,a large number of studies on memory system have been conducted based on the information processing theo... Vocabulary acquisition is an intricate process,which has a close relationship with memory.In cognitive psychology,a large number of studies on memory system have been conducted based on the information processing theory,placing great value on second language learners’cognitive process.This study intends to probe into second language vocabulary acquisition from the perspective of information processing theory in hope to help learners acquire vocabulary more scientifically and efficiently. 展开更多
关键词 Second language vocabulary acquisition information processing theory Cognitive process
下载PDF
Chemical Reactivity Description in Density-Functional and Information Theories 被引量:2
16
作者 NALEWAJSKI Roman F. 《物理化学学报》 SCIE CAS CSCD 北大核心 2017年第12期2491-2509,共19页
In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generate... In Quantum Information Theory(QIT) the classical measures of information content in probability distributions are replaced by the corresponding resultant entropic descriptors containing the nonclassical terms generated by the state phase or its gradient(electronic current). The classical Shannon(S[p]) and Fisher(I[p]) information terms probe the entropic content of incoherent local events of the particle localization, embodied in the probability distribution p, while their nonclassical phase-companions, S[ Φ ] and I[ Φ ], provide relevant coherence information supplements.Thermodynamic-like couplings between the entropic and energetic descriptors of molecular states are shown to be precluded by the principles of quantum mechanics. The maximum of resultant entropy determines the phase-equilibrium state, defined by "thermodynamic" phase related to electronic density,which can be used to describe reactants in hypothetical stages of a bimolecular chemical reaction.Information channels of molecular systems and their entropic bond indices are summarized, the complete-bridge propagations are examined, and sequential cascades involving the complete sets of the atomic-orbital intermediates are interpreted as Markov chains. The QIT description is applied to reactive systems R = A―B, composed of the Acidic(A) and Basic(B) reactants. The electronegativity equalization processes are investigated and implications of the concerted patterns of electronic flows in equilibrium states of the complementarily arranged substrates are investigated. Quantum communications between reactants are explored and the QIT descriptors of the A―B bond multiplicity/composition are extracted. 展开更多
关键词 Density-functional theory Donor-acceptor system Electronegativity equalization and electron flows information theory Markov chains PHASE-EQUILIBRIA
下载PDF
Relativistic Information Entropy on Uncertainty Analysis 被引量:2
17
作者 Jin Weiliang Han Jie Professor, Dr. -Eng., Dept. of Civil Engineering, Zhejiang University, Hangzhou, 310027 Lecturer. Dept. of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310027 《China Ocean Engineering》 SCIE EI 1996年第4期391-400,共10页
in this paper, a new approach to relativistic information entropy is used to assess some relative uncertainties in structural reliability assessment. This approach is composed of the information theory and the relativ... in this paper, a new approach to relativistic information entropy is used to assess some relative uncertainties in structural reliability assessment. This approach is composed of the information theory and the relativistic theory, and can be used to measure the relativity of parameter uncertainty and system uncertainty in structural reliability theory based on the same generalized relativistic reference system. Therefore, the structural reliability assessment can be assessed reasonably by the approach. 展开更多
关键词 structural reliability ENTROPY information theory relativity theory UNCERTAINTY probability. fuzzy set
下载PDF
Life Loss Estimation Based on Dam-Break Flood Uncertainties and Lack of Information in Mountainous Regions of Western China 被引量:1
18
作者 Chao Wang Sherong Zhang +2 位作者 Yaosheng Tan Fei Pan Lei Yan 《Transactions of Tianjin University》 EI CAS 2017年第4期370-379,共10页
Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly ... Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly applied in the estimation of dam-break flood loss. In particular, there is scant information regarding the conditions of affected area and hydrological characteristics in southwest China. In this paper, we introduce an integrated model for estimating flood loss that is adapted to the mountainous regions of southwestern China in light of the relative lack of available information. This model has three major components: a basic information model, a dam-routed flood propagation simulation model, and a loss estimation model. We established the basic information model despite the relative lack of available information using 3S technology [remote sensing (RS); geographical information system (GIS); global positioning system (GPS)], data mining technology, and statistical analysis techniques. Our dam-routed flood propagation simulation model consists of major hydrologic processes and their governing equations for flow propagation, which we solve using finite-difference schemes. In this model, the flood propagation area is divided into grids and each grid is determined by the characteristic parameters obtained from the propagation simulation. We present a case study of the Lianghekou hydropower station in Sichuan Province, China to illustrate the practical application of this integrated model for life loss estimation. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 DAMS ESTIMATION Finite difference method Flood damage Floods Geographic information systems Global positioning system information theory Remote sensing
下载PDF
Foundations and Applications of Information Systems Dynamics
19
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
下载PDF
Vertical structure of predictability and information transport over the Northern Hemisphere
20
作者 冯爱霞 王启光 +1 位作者 龚志强 封国林 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期661-668,共8页
Based on nonlinear prediction and information theory, vertical heterogeneity of predictability and information loss rate in geopotential height field are obtained over the Northern Hemisphere. On a seasonal-to-interan... Based on nonlinear prediction and information theory, vertical heterogeneity of predictability and information loss rate in geopotential height field are obtained over the Northern Hemisphere. On a seasonal-to-interannual time scale, the predictability is low in the lower troposphere and high in the mid-upper troposphere. However, within mid-upper troposphere over the subtropics ocean area, there is a relatively poor predictability. These conclusions also fit the seasonal time scale. Moving to the interannual time scale, the predictability becomes high in the lower troposphere and low in the mid-upper troposphere, contrary to the former case. On the whole the interannual trend is more predictable than the seasonal trend. The average information loss rate is low over the mid-east Pacific, west of North America, Atlantic and Eurasia, and the atmosphere over other places has a relatively high information loss rate on all-time scales. Two channels are found steadily over the Pacific Ocean and Atlantic Ocean in subtropics. There are also unstable channels. The four- season influence on predictability and information communication are studied. The predictability is low, no matter which season data are removed and each season plays an important role in the existence of the channels, except for the winter. The predictability and teleconnections are paramount issues in atmospheric science, and the teleconnections may be established by communication channels. So, this work is interesting since it reveals the vertical structure of predictability distribution, channel locations, and the contributions of different time scales to them and their variations under different seasons. 展开更多
关键词 geopotential height field information theory information loss rate PREDICTABILITY
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部