检索结果-内蒙古大学图书馆

Dynamics of coding in communicating with chaos

Physical Review E 1998年第2期58卷 1724-1724页

作者： Erik Bollt Ying-Cheng Lai Department of Mathematics 572 Holloway Road United States Naval Academy Annapolis Maryland 21402-5002 Department of Physics and Astronomy and Department of Mathematics The University of Kansas Lawrence Kansas 66045

Recent work has considered the possibility of utilizing symbolic representations of controlled chaotic orbits for communicating with chaotically behaving signal generators. The success of this type of nonlinear digital communication scheme relies on partitioning the phase space properly so that a good symbolic dynamics can be defined. A central problem is then how to encode an arbitrary message into the wave form generated by the chaotic oscillator, based on the symbolic dynamics. We argue that, in general, a coding scheme for communication leads to, in the phase space, restricted chaotic trajectories that live on nonattracting chaotic saddles embedded in the chaotic attractor. The symbolic dynamics of the chaotic saddle can be robust against noise when the saddle has large noise-resisting gaps covering the phase-space partition. Nevertheless, the topological entropy of such a chaotic saddle, or the channel capacity in utilizing the saddle for communication, is often less than that of the chaotic attractor. We present numerical evidences and theoretical analyses that indicate that the channel capacity associated with the chaotic saddle is generally a nonincreasing, devil’s-staircase-like function of the noise-resisting strength. There is usually a range for the noise strength in which the channel capacity decreases only slightly from that of the chaotic attractor. The main conclusion is that nonlinear digital communication using chaos can yield a substantial channel capacity even in noisy environment.

关键词： .Entropy phase space gaps trajectories partition utilizing chaotic attractor digital communication communicating with chaos message coding scheme topological symbolic dynamics noise-resisting chaotic saddles

来源：评论

学校读者我要写书评

暂无评论

Legal Forensics System Based on Data Mining

引用

Procedia Computer Science 2024年 243卷 1089-1094页

作者： Hongrui Dai Law school of Chongqing University Chongqing 400044 China Law school of Yunnan Minzu University Kunming 650504 China

The existing forensics systems are developing in a more and more perfect direction in terms of forensic steps, legal constraints, audit supervision, etc., but they are still not fully applicable to legal forensics. A general legal forensics system must have a complete forensics process to ensure the smooth progress of the forensics work. One of the purposes of legal forensics is to use legal means to bring criminals to justice. Only by ensuring the legality of the evidence can it be accurately identified case, and therefore also to ensure the legality of the evidence collection process. In order to design a more powerful legal forensics system, this paper introduces a data mining algorithm to extract valuable information from massive data through association rules to improve the efficiency of forensics. At the same time, this paper also proposes three coding schemes for the integrity of the evidence object, and compares the forensic effects of the three schemes.

关键词： Legal Forensics Data Mining Algorithm Association Rules coding scheme

来源：评论

学校读者我要写书评

暂无评论

Changes in the early communicative behaviors of young children with significant cognitive and motor developmental delays in a two-year span

引用

JOURNAL OF COMMUNICATION DISORDERS 2023年第1期104卷 106337-106337页

作者： Dhondt, Ann Van Keer, Ines van der Putten, Annette Maes, Bea Katholieke Univ Leuven Fac Psychol & Educ Sci Parenting & Special Educ Res Unit Leuven Belgium Univ Groningen Fac Behav & Social Sci Groningen Netherlands Vanderkelenstraat 32 Bus 3765 B-3000 Leuven Belgium

Introduction: This study examines longitudinal changes in communicative behavior of young children with significant cognitive and motor developmental delays (SDD) and determines their individual communicative trajectories. A second focus of this study is the relation of changes in communicative behavior with motor ***: Data consists of codes resulting from a self-developed coding scheme used on obser-vations of 23 children in three different settings and responses on a questionnaire. First, group trends were determined to find out whether communication-related variables tend to significantly change over the course of two years. Furthermore, these findings were contrasted with the in-dividual trajectories of the children. Next, the association of initial communicative skills and (the acquisition of) specific motor skills with the change in their communicative functioning was studied. Wilcoxon Signed Ranks and correlational analyses were used to answer the research ***: Out of sixteen different variables related to communicative behavior, ten changed significantly over the course of two years. Children with more focus on prompt on the first datapoint showed a significantly larger increase of signs of functionality. Still, all children showed highly individual trajectories. Children with better motor skills on the first datapoint showed a significantly larger increase in communication ***: Results show that if a myriad of detailed variables are taken into account children with significant cognitive and motor developmental disabilities do change regarding their communicative functioning, but that they tend to all show unique developmental trajectories. Children with stronger skills in some aspects of communication and motor functioning, can be considered advantaged regarding their communicative development.

关键词： Early communicative behaviors Children with significant cognitive and motor developmental delays PIMD coding scheme Communication complexity

来源：评论

学校读者我要写书评

暂无评论

On the feedback capacity of the first-order moving average Gaussian channel

引用

JAPANESE JOURNAL OF STATISTICS AND DATA SCIENCE 2019年第2期2卷 491-506页

作者： Ihara, Shunsuke Nagoya Univ Grad Sch Informat Chikusa Ku Huro Cho Nagoya Aichi 4648601 Japan

In this paper, we study the discrete-time additive Gaussian noise channel given by Yi=Xi+Zi, i=1,2,..., where the input signal {Xi} satisfies an average power constraint and the noise {Zi} is a stationary Gaussian process. We are interested in the capacity of the channel with feedback. Despite numerous lower and upper bounds having been reported, except for some special cases, it is an open problem to find the closed form for the feedback capacity. In the paper, we consider the case where the Gaussian noise {Zi} is a first-order moving average process defined by Zi=Wi+alpha Wi-1, |alpha|<= 1, with white Gaussian innovations Wi, i=0,1,2,.... For this channel, Kim (IEEE Trans Inf Theory 52(7):3063-3079, 2006;IEEE Trans Inf Theory 56(1):57-85, 2010) showed that a modified Schalkwijk-Kailath scheme achieves the feedback capacity and obtained the closed form of the feedback capacity. The main aim of the paper is to give a new proof of the optimality of the coding scheme given by Kim. In our proof, decompositions of the input signal Xi and the Gaussian innovation Wi into independent components play important roles. For this channel, the minimum decoding error probability decreases with an exponential order which linearly increases with block length.

关键词： Channel capacity Gaussian channel Feedback Moving average process coding scheme

来源：评论

学校读者我要写书评

暂无评论

Channel Correlation Maps for Rate-Adaptive MIMO-OFDMA Systems

Channel Correlation Maps for Rate-Adaptive MIMO-OFDMA System...

引用

IEEE Vehicular Technology Conference

作者： Huijun Li Huan Wang Gerd Ascheid Institute for Communication Technologies and Embedded Systems RWTH Aachen University

ISBN: (纸本)9781479944811

Channel frequency and spatial correlation are essential for adaptive channel prediction, which enables flexible scheduling. This correlation information is determined by the environment and can be learned and stored in a map to avoid online tracking. In this paper we propose a method to generate a channel frequency-spatial correlation map from the measurement campaign. Only two position-dependent parameters are stored in the map and the spatial atuocorrelations of the parameters are examined to interpolate channel correlation for the unmeasured positions. Adaptive unbiased prediction of channel gain based on the correlation map is used to compensate the outdated channel state information. The performance of flexible modulation and coding schemes using the distribution of predicted channel gain is shown through numerical simulation.

关键词： MIMO communication OFDM modulation adaptive scheduling channel estimation correlation theory frequency division multiple access prediction theory adaptive unbiased channel prediction channel correlation interpolation channel frequency-spatial correlation map channel state information coding scheme correlation information flexible modulation multiple-input multiple-output system online tracking orthogonal frequency-division multiple access position-dependent parameter predicted channel gain distribution rate-adaptive MIMO-OFDMA system scheduling flexibility spatial autocorrelation Antenna measurements Antennas Correlation Delays Frequency measurement Indexes OFDM Orthogonal frequency division multiplexing Frequency division multiaccess adaptive scheduling Channel state information labeling scheme Prediction theory correlation theory Antenna measurements MIMO communication frequency measurement multiple input multiple output systems ANTENNA channel estimation maps OFDMA

来源：评论

学校读者我要写书评

暂无评论

Cooperation in healthcare - theoretical and methodological issues: a study of two situations: hospital and home care 05

Cooperation in healthcare - theoretical and methodological i...

引用

Proceedings of the 2005 annual conference on European association of cognitive ergonomics

作者： Saliha Hamek Françoise Anceaux Sylvia Pelayo Marie-Catherine Beuscart-Zéphir Janine Rogalski Le Mont Houy Valenciennes EVALAB CERIM Faculté de Médecine Lille cedex Laboratoire Cognition et Usages-Lutin Saint Denis

ISBN: (纸本)9789602546567

The aim of the study is to test a coding method beyond the domain for which it was designed. Indeed, the considered method was developed to analyze cooperation in highly dynamic environments (Air Traffic Control, piloting). In such environments, the situation changes quickly, and the cooperation is generally synchronous, horizontal and entails the "copresence" of other operators. In this paper, the method is examined in the medical domain, in two healthcare situations whose dynamics are moderate or slow. The first one, Medication Ordering in the hospital setting, involves synchronous cooperation with face-to-face communication, and is organized vertically by means of physician-nurse task distribution. The second one, Homecare, involves asynchronous cooperation with written communication and is organized horizontally to facilitate cooperation between nurses who accomplish tasks of a identical nature at different times. The results obtained seem promising, insofar as the method allows both the coding of the written and oral communication and the identification of the most important properties of the different kinds of cooperation. Nevertheless, the coding is not able to take all the cooperative activity occurring in such dynamic situations into account.

关键词： coding scheme healthcare asynchronous cooperation distributed cooperation

来源：评论

学校读者我要写书评

暂无评论

The Comparison of GSM-EDGE Signal Transmission over AWGN and Rayleigh Fading Channel

The Comparison of GSM-EDGE Signal Transmission over AWGN and...

引用

Power Electronics Specialists Conference, 2008 IEEE;Prague,Czech Republic

作者： Filip GLEISSNER Stanislav HANUS Department of Radio Electronics Brno University of Technology Brno Czech Republic

ISBN: (纸本)9781424420872;9781424420889

This paper is concerned with GSM-EDGE system simulation and bit error ratio evaluation of the transmitted signal over AWGN and Rayleigh fading channel. The goal is to observe the impact of radio channel on variously modulated and coded GSM-EDGE signals. The block scheme and proposed model of signal processing in the downlink direction is described step by step. Simulation results for various modulation and coding schemes (MCS) are graphically presented. In order to get the required results, the simulation tool was created in MATLAB environment.

关键词： GSM-EDGE Modulation coding scheme AWGN Rayleigh Channel CNR BER

来源：评论

学校读者我要写书评

暂无评论

GA-Based Speaking Mouth Correlative Speech Feature Abstraction

GA-Based Speaking Mouth Correlative Speech Feature Abstracti...

引用

Firth IEEE International Conference on Cognitive Informatics(第五届认知信息国际会议)

作者： Xibin Jia Baocai Yin Yanfeng Sun Xianping Lin Multimedia and Intelligent Software Technology Beijing Municipal Key Laboratory Beijing University of Technology Beijing 100022 China

ISBN: (纸本)9781424404759

The image-based lip animation synthesis approach is one kind of promising method that synthesizes the believable talking head This paper seeks to show an improvement in the accuracy of mouth prediction with the speech stimulus, as well as showing the method used to extract the speaking mouth correlative speech feature. Our lip animation synthesis system is based on the construction of a frame level audiovisual mapping model between the acoustic speech class and speaking mouth image class. Taking the mapping model as a basis, genetic algorithm is used to extract the speaking mouth correlative speech feature. The key step used in this study is: fitness and coding scheme designing. Experimental results show that the extracted speech feature has a better correlation with the corresponding speaking mouth, compared to the single or mixed LPCC and MFCC. More research will be done in this specialist field of study the multi-layer speaking mouth correlative speech feature abstraction structure, and will attempt to show that the speaking mouth correlative speech feature should have better results.

关键词： audiovisual mapping speech processing speaking mouth correlative speech feature abstraction fitness designing coding scheme

来源：评论

学校读者我要写书评

暂无评论

Achieving the Secrecy Capacity on Strong Security Using LT Code with Polar Code Pre-coding

Achieving the Secrecy Capacity on Strong Security Using LT C...

引用

2016 10th IEEE International Conference on Anti-counterfeiting,Security,and Identification (ASID)

作者： Guangyu Yang Mingjie Zhuang College of Engineering Huaqiao University

Coset coding is often used in the study of the physical layer security based on wiretap channel *** almost every secure coding schemes using coset codes need a precise prediction of the channel state information(CSI),they are much more difficult to *** solve this problem,we propose a concatenated coding scheme combined of polar code and fountain code in wiretap channel model on binary memoryless erasure channels,achieving the strong security condition without the need for *** ordinary secure coding,we add fountain code after the coset encoding,making the code become a rateless ***,we illustrate the details of our scheme,and prove its security using information theory analysis ***,we give the result of our coding scheme against finite code length with limited security in *** shows our scheme works well when the code length is big *** last,two possible main reasons are discussed for the loss of coding rate.

关键词： security polar code LT code coding scheme wiretap channel

来源：评论

学校读者我要写书评

暂无评论

Capacity regions for multiple unicast flows using inter-session network coding 07

Capacity regions for multiple unicast flows using inter-sess...

引用

Proceedings of the 3rd international conference on Wireless internet

作者： Abdallah Khreishah Chih-Chun Wang Ness B. Shroff Purdue University The Ohio State University

ISBN: (纸本)9789639799127

In this paper we consider the problem of transmitting packets through multiple unicast sessions when inter-session linear network coding is permitted. We propose and formulate two new capacity regions for this problem. Distributed rate allocation algorithms and coding schemes are also provided for these capacity regions. The two capacity regions are compared with other known capacity regions in the literature to represent their benefits in terms of throughput, fairness, complexity, and ease of implementation.

关键词： capacity region multiple-unicast-sessions problem distributed algorithm inter-session network coding rate control coding scheme fairness

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：