• 제목/요약/키워드: Telecommunication

검색결과 6,376건 처리시간 0.037초

Ergonomic Approaches to Content Creation for 3D Displays

  • Kawai, Takashi;Kishi, Shinsuke;Kim, Sang-Hyun;Yamazoe, Takashi;Shibata, Takashi;Inoue, Tetsuri;Sakaguchi, Yusuke;Okabe, Kazushige;Yasuhiro, Kuno
    • Journal of Information Display
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    • 제8권1호
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    • pp.26-31
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    • 2007
  • This paper presents ergonomic approaches to editing and evaluating content for 3D displays. Two systems, a nonlinear editing system and an evaluation system, were developed to improve viewing safety and comfort for 3D content observers and provide better usability for the creators from the viewpoint of ergonomics.

Advanced Sensing Techniques of Energy Detection in Cognitive Radios

  • Wang, Han-O;Noh, Go-San;Kim, Dong-Kyu;Kim, Sung-Tae;Hong, Dae-Sik
    • Journal of Communications and Networks
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    • 제12권1호
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    • pp.19-29
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    • 2010
  • Recently, spectrum sensing has been intensively studied as a key technology in realizing the cognitive radio. There have been advances in the performance of spectrum sensing through both multi-antenna and cooperative sensing schemes. In this paper, the performances and complicated scenarios of the latest spectrum sensing schemes are analytically compared and arranged into a technical tree while considering practical concerns. This paper will give a macroscopic view of spectrum sensing and will also provide insight into future spectrum sensing works.

뇌서지에 의한 전력통신선로의 전위상승 (A Rise in Electric Potential of Telecommunication Line for Electric Power System by Lightning Surges)

  • 이복희;장석훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 E
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    • pp.1718-1720
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    • 1997
  • This paper deals with n rise in electric potential of telecommunication line for electric power system by lightning surges. When $1.2/50{\mu}s$ and $8/20{\mu}s$ impulse voltage and current were applied on telecommunication cable, the voltage waveforms at the end terminal and equipment were measured. The telecommunication lines, which consist of 60 conductors and 3.5km in length, have some surge protectors such as preposition lightning arrester and TVSS. In each case, the rise in electric potential was measured for differential mode and common mode, respectively. Also, the rise in ground potential and the induced voltages were measured and analyzed. As a result, a significant rise in ground potential was observed for lightning surge. It can cause failure or malfunction of telecommunication systems.

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RFID 리더용 이중대역 도체스트립 개방루프 안테나 (Dual-band Open Loop Antenna using Strip-conductor for an RFID Reader)

  • 임정현;강봉수;김지윤;김흥수;양두영
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.63-64
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    • 2006
  • In this paper, the open loop antenna using a strip-conductor for an RFID reader at dual-band frequency(910MHz, 2.45GHz) is proposed. The impedance is matched by varying the antenna parameters such as the length of strip-conductor and the gap of between two strip-conductors. Return loss and gain of designed antenna are -11.919dB, 2.5dBi at 910MHz, and -15.766dB, 5.65dBi at 2.45GHz, respectively.

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Phase Shitf Orthogonal Sequence를 이용한 OFDMA 상향 링크 시스템에서의 시간 및 주파수 오차 추정 알고리즘 (Joint Timing and Frequency Offset Estimation in OFDMA Uplink Systems Using Phase Shift Orthogonal Sequence)

  • 민현기;주형식;이성은;곽경철;홍대식
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.159-160
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    • 2006
  • We present a multiuser synchronization scheme for OFDMA uplink systems. First a new preamble structure is proposed by which timing and frequency offsets estimation is developed. Based on proposed structure a new joint synchronization scheme is presented and the simulation results show that the performance of this scheme don't suffer from the number of users.

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OFDM FFT용 저전력 Radix-4 나비연산기 구조 (Low-Power Radix-4 butterfly structure for OFDM FFT)

  • 김도한;김비철;허은성;이원상;장영범
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.13-14
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    • 2006
  • In this paper, an efficient butterfly structure for Radix-4 FFT algorithm using DA(Distributed Arithmetic) is proposed. It is shown that DA can be efficiently used in twiddle factor calculation of the Radix-4 FFT algorithm. The Verilog-HDL coding results for the proposed DA butterfly structure show 61.02% cell area reduction comparison with those of the conventional multiplier butterfly structure. Furthermore, the 64-point Radix-4 pipeline structure using the proposed butterfly and delay commutators is compared with other conventional structures. Implementation coding results show 46.1% cell area reduction.

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방송과 통신정책, IPTV 융합정책의 지대추구론적 분석 : 지대추구의 효율성 분석을 중심으로 (A Study on the Convergence Policy of Broadcasting and Telecommunication in IPTV Convergence Service with Reference to Rent Seeking Theory)

  • 이상호;김재범
    • Journal of Information Technology Applications and Management
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    • 제14권3호
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    • pp.199-225
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    • 2007
  • This study deals with the regulatory policy of government on the convergence of broadcasting and telecommunication by applying rent seeking theory to Internet Protocal TV (IPTV). Existing literature has mainly focused on the negative implications of rent seeking since Tullock [1967], Krueger [1974] and Buchanan [1980]. We have investigated the regulatory policy along with the progress of the convergence of broadcasting and telecommunication. Regulatory policy on broadcasting, despite its impartial intent. has created the entry barrier in the industry, resulting in high rents. Meanwhile, regulatory policy in telecommunication is more geared by the encouragement of more competitive environments, resulting in reasonably low rents in the market. Regulatory policy in the age of convergence needs to improve the efficacy of the industry and welfare, while maintaining the rent at a reasonably low level. This research has contributed to emphasizing the positive aspect of rent seeking in policy concerned with the convergence of broadcasting and telecommunication, notably IPTV.

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통신망의 경제적 감가상각 적용방안 (A Study on applied methods of Economic Depreciation in Telecommunication Network)

  • 송연경
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2002년도 춘계종합학술대회
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    • pp.411-414
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    • 2002
  • 통신산업에서의 감가상각비는 기업이 국가에 납부해야 한 법인세와 통신요금의 산정뿐만 아니라 통신사업자의 수익성 판단과 국민 후생적인 측면에도 영향을 미치므로 그만큼 중요한 문제이다. 따라서 본고에서는 이미 많은 나라에서 다양하게 개발한 고정망 LRIC 모형과 영국 이동망 LRIC 모형을 살펴보고 이를 토대로 통신망에서 적용 가능한 여러 가지 감가상각 방안을 제시해 보고자 한다. 또한 시뮬레이션을 통해 각 방안별로 감가상각비를 비교해 봄으로써 국내 통신망 원가산정방법 및 정책 결정시 유용한 정보를 제공할 수 있을 것이다.

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댁내통신설비의 운영환경에 관한 연구 (Study on the Operational Environment of Customer Premise Telecommunication Facilities)

  • 이영환;이상무;조평동;류명주;서태석
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 추계종합학술대회
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    • pp.426-429
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    • 2001
  • 댁내통신설비는 통신망에서 중요한 역할을 한다. 현재 국내의 댁내통신설비에 대한 기술은 멀티미디어 환경을 반영하여 작성되었으나, 초고속정보통신망의 멀티미디어서비스를 수용하기 위해서는 미흡하다. 이에 본 논문에서는 댁내통신설비의 고도화를 위하여 운영환경요소를 분석하고 국내외 표준화 현황을 살펴보고 현재의 댁내통신설비의 운영환경에 대한 현장조사를 통한 문제점과 개선방안을 제시하였다.

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이동 단말기를 이용한 흠 오토메이션 서비스 기능 설계 및 구현 (Design and Implementation of the Functions for HomeAutomation Service Using Mobile Station)

  • 곽창준;김대광;박용수;이양승;권순량
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2002년도 추계학술발표논문집 (중)
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    • pp.1551-1554
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    • 2002
  • 홈 오토메이션은 댁내의 가전제품을 네트워크로 연결시켜 단말기를 이용하여 어디서든지 편리하게 가전제품을 제어하는 기술이다. 본 논문은 고정된 공간에서 유선 인터넷 망에 접속하던 PC환경에서 벗어나 휴대성과 이동성의 특징을 가지는 이동 단말기를 이용하여 이동 중에도 무선 인터넷에 접속하여 실시간으로 댁내의 가전제품을 제어할 수 있으며, 또한 비용적인 측면과 효율적인 측면을 고려하여 PC의 프린트 포트를 통하여 가정내의 가전제품을 제어하는 홈 오토메이션 서비스 기능의 설계 및 구현에 초점을 맞추고 있다.

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