• 한국전자파학회논문지
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• 제19권12호
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• pp.1470-1481
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• 2008

최근 수년간 IT기술의 급속한 발전으로 방송통신 융합현상이 전개되면서 전 세계적인 주파수 수요의 급증과 공급의 부족현상은 아날로그/디지털 공존기 이후 아날로그TV가 중단되었을 때, 각 국가에서 확보할 수 있는 저대역 주파수의 효율성을 극대화하는 활용방안을 마련하기 위해 주파수 회수/재배치 정책에 초점을 맞추게 하고 있다. 또한, WRC-07에서 전 세계 3G와 4G 이동통신서비스에 공통적으로 사용될 추가 주파수대역으로 $450{\sim}470\;MHz$, $2.3{\sim}2.4\;GHz$, $698{\sim}806\;MHz$, $3.4{\sim}3.6\;GHz$의 총 428 MHz 대 역 폭을 분배하였고, 디지털TV 잔여대 역중 일부를 IMT 공통대역으로 채택한 것은, 방송과 통신의 융합환경 속에서 지속적으로 발전하고 있는 이동통신 기술과 아날로그TV를 종료하고 디지털TV로 전환하고 있는 추세에 맞추어, 전 세계적으로 통신효율이 우수한 700/800/900 MHz 저대역 주파수의 확보를 갈망하고 있는 결과라고 볼 수 있다. 이에 우리나라도 이미 주파수분배를 변경하여 $752{\sim}806\;MHz$ 대역의 방송업무는 디지털TV 전환기간에 한하여 사용할 수 있도록 고시하였으며, 최근 제정된 "지상파텔레비전방송과디지털방송의활성화에관한특별법" 제7조는 아날로그 텔레비전 방송(ATV)의 종료일은 2012년 12월 31일 이전까지의 범위에서 정하도록 규정하였다. 또한, 현재 디지털 코드없는 전화기(DCP)용으로 사용 중인 $914{\sim}915\;MHz$ 및 $959{\sim}960\;MHz$ 대역의 주파수는 2013년 12월 31일까지 사용한다고 규정하여, 향후 900 MHz 대역의 회수/재배치 가능성을 열어두고 있다. 따라서 통신효율이 우수한 저대역 주파수의 발굴을 위하여, 현행 전파법상 주파수 회수/재배치 제도의 적극적인 활용방안을 모색해 보아야 할 것이다.

• 천문학회지
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• 제38권2호
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• pp.103-106
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• 2005

The Submillimeter Array (SMA), a collaborative project of the Smithsonian Astrophysical Observatory (SAO) and the Academia Sinica Institute of Astronomy & Astrophysics (ASIAA), has begun operation on Mauna Kea in Hawaii. A total of eight 6-m radio telescopes comprise the array with currently working receiver bands at 230, 345, and 690 GHz. The array will have 8 receiver bands covering the frequency range of 180-900 GHz. The backend is flexible analog-digital correlator with a full bandwidth of 2GHz, which is very powerful to cover several line emissions simultaneously. The current status and future plans of the SMA are described with emphasis on Taiwanese efforts.

• 한국안전학회지
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• 제14권4호
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• pp.182-191
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• 1999

Product liability(PL) and product safety(PS) is one of the most costly and confusing problems facing manufacturing today. Accordingly, this paper presents an integral process for product safety and product liability resulting from a defective product and proposes countermeasures of PL and PS for the four types of risk based on severity and frequency. Finally, we have presented a framework and practical procedure to provide the manufacturer with useful way of analyzing the risk potential of consumer products.

• ETRI Journal
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• 제25권4호
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• pp.211-218
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• 2003

This paper presents a dynamic resource allocation algorithm with multi-frequency time-division multiple access for the return link of interactive satellite multimedia networks such as digital video broadcasting return channel via satellite systems. The proposed timeslot assignment algorithm, called the very efficient dynamic timeslot assignment (VEDTA) algorithm, gives an optimal assignment plan within a very short period. The optimality and computational efficiency of this algorithm demonstrate that it will be useful in field applications.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.63-64
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• 2005

This paper proposed a miniaturization passive element employing the multiple microstrip line. As a result of this method, we realized the transmission line miniaturized. The applying structure designed and evaluated a power divider on GaAS MMIC circuit. It draws a plan in a center Frequency as the observation could do good characteristic.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.401-405
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• 2005

This paper proposed a miniaturization passive element employing the multiple microstrip line. As a result of this method, we realized the transmission line miniaturized. The applying structure designed and evaluated a power divider on GaAS MMIC circuit. It draws a plan in a center Frequency as the observation could do good characteristic.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1741-1743
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• 2003

In this paper, We presents the actual condition of domestic 170kv GIS(Gas Insulated Swichgear)- Electrical Facilities of Private Use be examined by post. We are able to confirm the distribution characteristic analysis of GIS failure- type of industry, occurrence frequency, part and counter plan research for failure preventing.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.319-322
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• 2007

This study aims to find the characteristics of damage and states of natural disasters at the Korean Peninsula from 1985 to 2004. Using the data of Statistical yearbook of calamities issued by the National Emergency Management Agency and Annual Climatological Report issued by the Korea Meteorological Administration. we have analyzed the cause, elements, and vulnerable regions for natural disasters. Major causes of natural disaster at Korean Peninsula are four, such as a heavy rain, heavy rain typhoon, typhoon, storm snow, and storm. The frequency of natural disaster is the highest from June to September. The period from December to March also shows high frequency. The total amount of damage is high during the summer season(Jul.-Sept). The period from January to March shows relatively high amount of damage due to storm and storm snow The areas of Gangwon-do, Gyeongsangnam-do and Gyeongsangbuk-do are classified the vulnerable region for the natural disasters. By establishing mitigation plans which fit the type and characteristics of disaster for each region, damage from disaster can be reduced with efficient prevention activities.

• 디지털산업정보학회논문지
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• 제4권4호
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• pp.31-39
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• 2008

RFID diffusion and origin technique being developed gradually, according to the various branch application solutions are coming out plentifully. Developed distance variable style 2.45 Ghz Active Tag from the present paper and according to century of corresponding frequency the distance of the leader and the tag between should have been falling as will freeze, will be able to grasp in order. The experimental result plan develops the data which measures from field test and the electromagnetic waves laboratory with base.

• 한국학교ㆍ지역보건교육학회지
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• 제15권2호
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• pp.13-22
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• 2014

Objectives: The purpose of this study was to identify drinking form and analyze affecting factors of emergency medical technology students. Methods: Data were collected by questionnaire and analyzed by using the SPSS WIN 18.0 and Multiple Linear Regression Analysis. Results: In factors of the monthly drinking frequency, start drinking(middle school), smoking, pocket money, education level of mother were statistically profitable(p<.05). In factors of the monthly drinking too much frequency, gender, education level of mother, start drinking(high school), economical level were statistically profitable(p<.05). In factors of subjective model of drinking, discord with parents, education level of mother, age were statistically profitable(p<0.05). Conclusion: Teacher and the authorities of school and government must know seriousness and importance of drinking and endeavor to solve the problem and prepare the political plan and solution.