• 제목/요약/키워드: Communication Sciences

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AM 방식의 수중통신 (An underwater communication by AM technic)

  • 서호선;차일환
    • 한국통신학회:학술대회논문집
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    • 한국통신학회 1984년도 춘계학술발표회논문집
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    • pp.33-36
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    • 1984

  • An underwater communication technic using AM modulated ultrasonicwave was studied. The experiment were performed in the ahechoic water tank with 60KHz carrier wave and the frequency response of the system by demodulated signals were measured varing the degree of modulation and distance between transmitter and receiver. The bandwidth of transmitted signals was limited by the acoustic characteristics. As the result, it was found out that this kind of system is applicable to the underwater speech communication.

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이조말통신제도의 역사적 고찰 (A Historical Study of the Communication System in the Later Part of the Lee-Dynasty)

  • 신상각
    • 한국통신학회논문지
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    • 제3권1호
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    • pp.8-17
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    • 1978

  • The later part of the Lee-Dynasty was a period that marked an important turning point in the history of the modern communication system in our country. This paper proposes to research the historic process of initiation and development of the modern communication system in that period through the communication administrative organ and the installation of the wire communication lines such as wastward lines, southward lines and northward lines extended from Han Seung (Seoul) as well as the submarine cables from Korea to Japan. The modernization of the communication system in our country had been achieved in the struggle of national uprising spirits of Korean people against the invasive avarices of the neighbouring nations such as Japan and China. The initiation of the modern communication system played a leading role in civilizing our country. Thus the fair spirits of our forerunners who had schemed to develop the independent communication system should be valued enormously.

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