• 제목/요약/키워드: communication technology

검색결과 16,760건 처리시간 0.056초

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
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.260-262
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    • 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.

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The Study about the Bluetooth Communication

  • Song, Zhenghua;Shin, Hyun-Sik;Kim, Chun-Suk
    • 한국전자통신학회논문지
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    • 제2권3호
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    • pp.180-184
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    • 2007
  • Bluetooth is a standard for short range, low power, low cost wireless communication that uses radio technology. This paper presents an overview of Bluetooth communication the following article will focus on the formation of Bluetooth scatter nets and some proposed scatter net models.

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Green Cooperative Sensing Scheme in Heterogeneous Networks

  • Shen, Lifei;Liu, Jian;Tan, Xinxin;Wang, Lei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권2호
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    • pp.550-565
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    • 2018
  • Cognitive radio technology is still the key technology of future mobile communication systems. Previous studies have focused on improving spectrum utilization and less energy consumption. In this paper, we propose an Overhead Reduced Scheme (ORS) for green cooperative spectrum sensing. Compared to traditional cooperative sensing scheme, ORS scheme divides the sensing time into three time slots and selects the best multi-mode user to report decisions. In consideration of reporting channel deviation, we derive closed-form expressions for detection probability and false alarm probability of ORS scheme based on Rayleigh fading channel. Simulation results show that ORS scheme can improve the perception accuracy while reducing the perceived delay and energy consumption in the process of perception, so as to realize the green communication.

DNP3.0을 이용한 과전류 계전기 에이전트의 통신 방안 연구 (A Study on communication method between OverCurrent Relay Agents using DNP 3.0)

  • 이한웅;정광호;임성일;현승호;최면송;이승재
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.265-267
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    • 2002
  • In this paper, the communication between Over-Current Relay agents is realized using DNP(Distributed Network Protocol), which is the standard communication protocol of distribution automation system in KEPKO. The key words in OCR agent communication are defined and represented by use of DNP application function code. And the DNP index for OCR agent is defined. The proposed communication scheme is tested by use of Communication Test Harness, a test tool for DNP protocol to show its soundness.

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The Impact of Social Media Marketing Towards Purchase Decision: Interactive Flat Panel Display Technology Distribution from Indonesia's B2B Market

  • Yunita SWASTI;Ricardo INDRA;Nadia Kris SIGIT;Muhammad ILHAM;La MANI;Muhammad ARAS
    • 유통과학연구
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    • 제22권9호
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    • pp.129-139
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    • 2024
  • Purpose: This research aims to examine the impact of social media marketing on buy decisions in Indonesia's B2B market, considering the mediating roles of brand image, perceived quality, and perceived value in relation to interactive flat panel display technology. To better understand technology adoption and distribution, we utilize the innovation diffusion theory. Research Design, Data and Methodology: The Decision-Making Unit of each organization that buy interactive flat panel display technology conducted an empirical survey of 82 participants. The quantitative research design analyzed the data utilizing the PLS-SEM model. outcome: This research reveals that social media marketing significantly impacted perceived quality, brand image, perceived value, and buy decisions. The research also found that perceived quality does not significantly impact buy decisions, but perceived value and brand image significantly impacted buy decisions. This research contributes to understanding the key factorsinfluencing buy decisionsin Indonesia's B2B market. Conclusion: Thisresearch concludesthat B2B consumers in Indonesia are less concerned about product quality but prioritize the value they receive when purchasing interactive display technology. Social media marketing could impacted the distribution of interactive display technology in Indonesia's B2B market by affecting the DMU's purchasing decisions. Brands should leverage social media marketing to positively impact theirsuccess.

스마트 철도 통신기반 위험요인에 따른 정보보호 방안 (Information Security Strategy by Risk Factors based on Smart Railway Communications)

  • 박은경
    • 한국전자통신학회논문지
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    • 제17권4호
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    • pp.695-702
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    • 2022
  • 최근 들어 활발하게 연구되고 있는 스마트 철도 시스템은 통신기술과 정보기술 등 ICT(: Information & Communication Technology) 기반으로 자동화 단계를 넘어 지능화 단계로 진입하고 있다. 스마트 철도에 사용되고 있는 ICT 기술은 일반적으로 정보침해에 취약한 특성을 보여 다양한 정보보호 기술의 지원을 받고 있다. 고속/대량 운송 수단으로서 철도 시스템의 스마트화에는 그 기반을 이루는 ICT 기술을 위한 정보보호 방안의 강구가 필수적이다. 따라서 본 논문에서는 스마트 철도 통신기반의 잠재적 위험 요인을 살펴보고 이에 대응할 수 있는 정보보호 요소를 고찰하여 스마트 철도 통신을 위한 단계별 정보보호 방안의 필요성을 제시한다.

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)
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    • 제10권4호
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    • pp.1590-1610
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    • 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.

Systematic Approach for Design of Broadband, High Efficiency, High Power RF Amplifiers

  • Mohadeskasaei, Seyed Alireza;An, Jianwei;Chen, Yueyun;Li, Zhi;Abdullahi, Sani Umar;Sun, Tie
    • ETRI Journal
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    • 제39권1호
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    • pp.51-61
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    • 2017
  • This paper demonstrates a systematic approach for the design of broadband, high efficiency, high power, Class-AB RF amplifiers with high gain flatness. It is usually difficult to simultaneously achieve a high gain flatness and high efficiency in a broadband RF power amplifier, especially in a high power design. As a result, the use of a computer-aided simulation is most often the best way to achieve these goals; however, an appropriate initial value and a systematic approach are necessary for the simulation results to rapidly converge. These objectives can be accomplished with a minimum of trial and error through the following techniques. First, signal gain variations are reduced over a wide bandwidth using a proper pre-matching network. Then, the source and load impedances are satisfactorily obtained from small-signal and load-pull simulations, respectively. Finally, two high-order Chebyshev low-pass filters are employed to provide optimum input and output impedance matching networks over a bandwidth of 100 MHz-500 MHz. By using an EM simulation for the substrate, the simulation results were observed to be in close agreement with the measured results.

4세대 이동통신의 국내외 표준화 연구 (A Local and International Standardization Survey on Forth Generation Mobile Communication)

  • 정영식;오행석;박기식;박치향
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 추계종합학술대회
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    • pp.207-211
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    • 2000
  • 다양한 종류의 데이터 서비스를 다양한 무선환경에서 다양한 요구품질을 만족시키면서 제공하는 이동통신 기술이라면 일차적으로는 제4세대 이동통신기술로 분류할 수 있다. 4세대 이동통신기술은 이동통신 시스템을 구성하는 각각의 구성 요소들이 현재까지의 제 2세대 및 현재 개발중인 제3세대 이동통신 기술과는 차별화 된 형태를 가져야 하며 3세대까지의 이동통신 기술에 비하여 보다 발전적이고 통합적인 형태를 띠어야 할 것이다 제4세대 이동통신의 핵심기술은 다음과 같은 기술을 포함하고 있다. Adaptive coding and modulation, Smart antenna, Interference cancellation, mechanism between various networks 본 논문에서는 이와 같은 기술들의 개발현황 및 표준화 현황에 대해 기술하고자 한다.

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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.
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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    • pp.1027-1032
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    • 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.

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