• Title, Summary, Keyword: Information and Communication Technology

Search Result 9,415, Processing Time 0.079 seconds

Trends Research and Development View of Power Line Communication (전력통신을 위한 시장 동향 및 발전 전망)

  • Kim, Ji-Ho;Lee, Hyang-Beom
    • 한국정보통신설비학회:학술대회논문집
    • /
    • /
    • pp.573-578
    • /
    • 2008
  • While going through economic development for several decades, Korea has become an industrialized country, and the development of industrial technology accelerated the advent of the information opportunity era. The recent information oriented society has brought forth the development of new information communication technology that enables anybody to obtain information easily and simply, and recently power line communication technology is being developed that allows the use of the existing power line net-works as they are. Each advanced country that faced up to a riffle effect of power line communication technology that enables us to obtain information easily anywhere at anytime is engaged in fierce competition to be a leader in this technology and to preoccupy the standardization of power line communication technology. At this point, this study is to help Korea take the lead in information communication technology by proposing a direction for the standardization that Korean power line communication technology needs to head for by identifying the trend of the worldwide of power line communication technology.

  • PDF

A PERFORMANCE STUDY OF SPEECH CODERS FOR TELEPHONE CONFERENCING IN DIGITAL MOBILE COMMUNICATION NETWORKS

  • Lee, M.S.;Lee, G.C.;Kim, K.C.;Lee, H.S.;Lyu, D.S.;Shin, D.J.;Lee, Hun
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • /
    • pp.899-903
    • /
    • 1994
  • This paper describes two methods to assess the output speech, quality of vocoders for telephone conferencing in digital mobile communication networks. The proposed methods are the sentence discrimiantion method and the modified degraded mean opinion score (MDMOS) test. We apply these two methods to Qualcomm code excited linear prediction (QCELP), vector sum excited linear prediction (VSELP) and regular pulse excited-long term predictin (RPE-LTD) voceders to evaluate which vocoding algorithm can process mixed voice signal from two speakers better for telephone conferencing. From the experiments we obtain that the VSELP vocoding algorithm reveals superior output speech quality to the other two.

  • PDF

Image Registration Improvement Based-on FFT Techniques with the Affine Transform Estimation

  • Wisetphanichkij, Sompong;Pasomkusolsil, Sanchaiya;Dejhan, Kobchai;Cheevasuvit, Fusak;Mitatha, Somsak;Sra-Ium, Napat;Vorrawat, Vinai;Pienvijarnpong, Chanchai
    • Proceedings of the KSRS Conference
    • /
    • /
    • pp.260-262
    • /
    • 2003
  • New Image registration techniques are developed for determining geometric distortions between two images of the same scene. First, the properties of the Fourier transform of a two dimensional function under the affine transformation are given. As a result, techniques for the estimation of the coefficients of the distortion model using the spectral frequency information are developed. Image registration can be achieved by applying the fast Fourier transform (FFT) technique for cross correlation of misregistered imagery to determine spatial distances. The correlation results may be rather broad, making detection of the peak difficult, what can be suppressed by enhancing cross-correlation technique. Yield greatly improves the delectability and high precision of image misregistration.

  • PDF

Attacks, Vulnerabilities and Security Requirements in Smart Metering Networks

  • Hafiz Abdullah, Muhammad Daniel;Hanapi, Zurina Mohd;Zukarnain, Zuriati Ahmad;Mohamed, Mohamad Afendee
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.4
    • /
    • pp.1493-1515
    • /
    • 2015
  • A smart meter is one of the core components in Advanced Metering Infrastructure (AMI) that is responsible for providing effective control and monitor of electrical energy consumptions. The multifunction tasks that a smart meter carries out such as facilitating two-way communication between utility providers and consumers, managing metering data, delivering anomalies reports, analyzing fault and power quality, simply show that there are huge amount of data exchange in smart metering networks (SMNs). These data are prone to security threats due to high dependability of SMNs on Internet-based communication, which is highly insecure. Therefore, there is a need to identify all possible security threats over this network and propose suitable countermeasures for securing the communication between smart meters and utility provider office. This paper studies the architecture of the smart grid communication networks, focuses on smart metering networks and discusses how such networks can be vulnerable to security attacks. This paper also presents current mechanisms that have been used to secure the smart metering networks from specific type of attacks in SMNs. Moreover, we highlight several open issues related to the security and privacy of SMNs which we anticipate could serve as baseline for future research directions.

CONTINUOUS DIGIT RECOGNITION FOR A REAL-TIME VOICE DIALING SYSTEM USING DISCRETE HIDDEN MARKOV MODELS

  • Choi, S.H.;Hong, H.J.;Lee, S.W.;Kim, H.K.;Oh, K.C.;Kim, K.C.;Lee, H.S.
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • /
    • pp.1027-1032
    • /
    • 1994
  • This paper introduces a interword modeling and a Viterbi search method for continuous speech recognition. We also describe a development of a real-time voice dialing system which can recognize around one hundred words and continuous digits in speaker independent mode. For continuous digit recognition, between-word units have been proposed to provide a more precise representation of word junctures. The best path in HMM is found by the Viterbi search algorithm, from which digit sequences are recognized. The simulation results show that a interword modeling using the context-dependent between-word units provide better recognition rates than a pause modeling using the context-independent pause unit. The voice dialing system is implemented on a DSP board with a telephone interface plugged in an IBM PC AT/486.

  • PDF

A 60GHz Wireless Cooperative Communication System Based on Switching Beamforming

  • Shi, Wei;Wang, Jingjing;Liu, Yun;Niu, Qiuna;Zhang, Hao;Wu, Chunlei
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.10 no.4
    • /
    • pp.1590-1610
    • /
    • 2016
  • The challenge of penetrating obstacles along with impact from weak multipath effects makes 60GHz signal very difficult to be transmitted in non-line of sight (NLOS) channel. So 60GHz system is vulnerable to obstructions and thus likely results in link interruption. While the application of cooperative technology to solve link blockage problemin 60GHz system should consider the characteristic of directional transmission for 60GHz signal. Therefore in this paper a system is proposed to solve the link blockage problem in 60GHz NLOS communication environment based on the concept of cooperation and also the beamforming technology, which is the basis of directional transmission for 60GHz communication system. The process of anti-blockage solution with cooperative communication is presented in detail, and the fast switching and recovery schemes are well designed. The theoretical values of symbol error rate (SER) using decode and forward (DF) cooperation and amplify and forward (AF) cooperation are presented respectively when the common channel interference exists. Simulation results demonstrate that the performance based on DF cooperation is better than the performance based on AF cooperation when directional transmission is used.

Classifier Combination Based Source Identification for Cell Phone Images

  • Wang, Bo;Tan, Yue;Zhao, Meijuan;Guo, Yanqing;Kong, Xiangwei
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.12
    • /
    • pp.5087-5102
    • /
    • 2015
  • Rapid popularization of smart cell phone equipped with camera has led to a number of new legal and criminal problems related to multimedia such as digital image, which makes cell phone source identification an important branch of digital image forensics. This paper proposes a classifier combination based source identification strategy for cell phone images. To identify the outlier cell phone models of the training sets in multi-class classifier, a one-class classifier is orderly used in the framework. Feature vectors including color filter array (CFA) interpolation coefficients estimation and multi-feature fusion is employed to verify the effectiveness of the classifier combination strategy. Experimental results demonstrate that for different feature sets, our method presents high accuracy of source identification both for the cell phone in the training sets and the outliers.

A Study on the Development and Application of Information Communication Technology into Mathematics Education (정보통신기술 활용교육의 수학교과 적용 방안 탐색)

  • 김민경;김유진
    • The Mathematical Education
    • /
    • v.42 no.1
    • /
    • pp.41-56
    • /
    • 2003
  • As the information society appears, the increasing power and access of personal computers along with wide spread use of the information technology has not only changed the landscape for communication but it has opened up new and exciting opportunities for education. One of the ways that information technology could help improve education is to be used in interactive communication to share the knowledge and experience of all the teachers as well as students. In this paper, the use and application of information communication technology[ICT] into mathematics classroom are described and showed several examples. furthermore, the web site design and developed for this study was introduced of the purpose of sharing the ideas about the knowledge and usage of the history of mathematics and examples of mathematical connections. The study suggests that enabling mathematics in incorporating of ICT by teachers and students requires more effort to be made in training teachers on the use and application of ICT into mathematics classroom.

  • PDF

Surface Centroid TOA Location Algorithm for VLC System

  • Zhang, Yuexia;Chen, Hang;Chen, Shuang;Jin, Jiacheng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.13 no.1
    • /
    • pp.277-290
    • /
    • 2019
  • The demand for indoor positioning is increasing day by day. However, the widely used positioning methods today cannot satisfy the requirements of the indoor environment in terms of the positioning accuracy and deployment cost. In the existing research domain, the localization algorithm based on three-dimensional space is less accurate, and its robustness is not high. Visible light communication technology (VLC) combines lighting and positioning to reduce the cost of equipment deployment and improve the positioning accuracy. Further, it has become a popular research topic for telecommunication and positioning in the indoor environment. This paper proposes a surface centroid TOA localization algorithm based on the VLC system. The algorithm uses the multiple solutions estimated by the trilateration method to form the intersecting planes of the spheres. Then, it centers the centroid of the surface area as the position of the unknown node. Simulation results show that compared with the traditional TOA positioning algorithm, the average positioning error of the surface centroid TOA algorithm is reduced by 0.3243 cm and the positioning accuracy is improved by 45%. Therefore, the proposed algorithm has better positioning accuracy than the traditional TOA positioning algorithm, and has certain application value.

Multi-resolution Image Registration

  • Wisetphanichkij, Sompong;Dejhan, Kobchai;Likitkarnpaiboon, Prayong;Cheevasuvit, Fusak;Sra-Ium, Napat;Vorrawat, Vinai;Pienvijarnpong, Chanchai
    • Proceedings of the KSRS Conference
    • /
    • /
    • pp.263-265
    • /
    • 2003
  • The computation cost of image registration is affected by searching data size and space. This paper proposes an efficient image registration algorithm that uses multi-resolution wavelet decomposed image to reduce the data size search. The algorithm determines the correlation detection at low resolution on low-pass sub bands of wavelet and generate mask for higher resolution as part of a coarse to fine registration algorithm. The correlation matching is defined for coarse resolution similarity measurement, while mutual information (MI) is used at fine resolution. The results show that the new efficient mask-based algorithm improves computational efficiency and yields robust and consistent image registration results.

  • PDF