• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.901-920
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• 2015

Wireless Sensor Networks (WSNs) are widely used in geographically isolated applications like military border area monitoring, battle field surveillance, forest fire detection systems, etc. Uninterrupted power supply is not possible in isolated locations and hence sensor nodes live on their own battery power. Localization of sensor nodes in isolated locations is important to identify the location of event for further actions. Existing localization algorithms consume more energy at sensor nodes for computation and communication thereby reduce the lifetime of entire WSNs. Existing approaches also suffer with less localization coverage and localization accuracy. The objective of the proposed work is to increase the lifetime of WSNs while increasing the localization coverage and localization accuracy. A novel intelligent unmanned aerial vehicle anchor node (IUAN) is proposed to reduce the communication cost at sensor nodes during localization. Further, the localization computation cost is reduced at each sensor node by the proposed intelligent arc selection (IAS) algorithm. IUANs construct the location-distance messages (LDMs) for sensor nodes deployed in isolated locations and reach the Control Station (CS). Further, the CS aggregates the LDMs from different IUANs and computes the position of sensor nodes using IAS algorithm. The life time of WSN is analyzed in this paper to prove the efficiency of the proposed localization approach. The proposed localization approach considerably extends the lifetime of WSNs, localization coverage and localization accuracy in isolated environments.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.85-92
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• 2008

Occurring forest fire or burning bushes beneath overhead transmission lines have caused breakdown disturbances of the system in many countries. In this study, experiments for flashover characteristics in the simulated condition of vertical power lines were conducted so as to investigate the reduction in insulation strength caused by combustion flame. As the results of an experimental investigation, it is demonstrated that flame can reduce breakdown voltages of the model lines according to height(h) of flame. The breakdown voltages were decreased with decreasing the height(h) of flame it can be seen that the average reduction of flashover levels, in comparison with the no-flame case, are 46.2[%] for h=9[cm] and 62.5[%] for h=3[cm] when ac voltage is applied.

• Proceedings of the KSRS Conference
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• 2001.03a
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• pp.49-55
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• 2001

본 연구에서는 GIS를 이용하여 산불관련 데이터베이스를 구축하고 효과적인 산불 현황정보 검색시스템을 개발하녀 산불 관리자에게 효율적인 공간분석 도구를 제공함으로서 산불에 관한 종합적인 공간정보를 빠른 시간 내에 분석하여 속성을 갱신·추출 할 수 있도록 하는 효과적인 GUI(Graphic User Interface)를 개발하였다. 이를 위하여 최근 10년간의 산불현황 통계자료를 이용한 전국 시·군단위의 공간분포도를 작성하여 전국 산불 발생현황을 시·공간적으로 분석하고 산불 발생에 미치는 다양한 요인들과의 상관성을 분석 가능하였다. 특히 최근 산불발생이 빈번한 삼척시의 지형도 및 임상도, 위성영상, 현지사진을 이용하여 GIS 데이터베이스를 구축함으로서 산불 발생위험지역에 대한 보다 상세한 정보를 얻을 수 있다. 본 시스템은 응용프로그램 개발을 위한 플랫폼은 IBM호환 PC에서 Windows 98을 운영체 제로 하여 DBMS는 Access 2000을 이용하였고 프로그래밍 언어로는 객체지향언어인 Visual Basic 6.0과 GIS 기능을 구현하기 위해서 Component GIS인 MapObjects 2.0을 사용 하였다. 그 결과 산불관리자는 진화에 필요한 관리구역내의 정보를 신속하게 제공받을 뿐만 아니라 산불방제사업에 대한 효과적인 의사결정지원과 함께 실무자 중심의 산불관리행정을 도모하 고 산림자원관리비가 효율적으로 이용될 것이다.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.65-65
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• 2011

도시의 확대와 산림의 개발을 통해 산불은 산지의 피해뿐만 아니라, 인접지에도 피해를 입히고 있다. 이는 일반적인 사례가 되어, 이에 대한 연구는 반드시 필요하다고 할 수 있다. 따라서, 본 연구에서는 경상북도의 울진군, 봉화군, 경주시를 대상으로 산림에 인접한 시설물의 빈도와 거리를 분석하여, 산불 발생 시 대피 및 진화 기준을 제시하고자 하였다. 조사 결과, 도시형으로 선정한 경주시가 전체 시설빈도가 가장 높았으며, 산악형으로 분류한 봉화군이 가장 빈도가 낮았다. 가옥의 빈도가 가장 높은 것으로 조사되었으며, 봉화군이 축사의 빈도가 특히 높은 것으로 조사되었다. 산림인접시설물의 산림과의 평균거리분석결과 산악형의 시설물의 평균 산림 인접 거리가 가장 가까우며, 도시형인 경주시의 인접거리가 가장 먼 것으로 조사되었다. 특히, 산악형(봉화 군)은 인접 시설의 산림과의 평균 거리가 100m이내인 것으로 조사되었으며, 산불 발생시 큰 피해가 예상되는 가옥, 의료/복지시설, 주유소, 축사 등 전 시설물의 산림인접 100m 이내 비율도 가장 높은 것으로 조사되었다. 따라서, 산불 발생 시 인접지의 피해가능성이 높은 산림 이격 거리를 100m 이내로 가정할 경우, 봉화군의 경우 산불발생 시 피해가 클 것으로 예상된다. 이러한 연구를 보다 확대하여 향후 산불 발생에 대비한 지역단위 진화와 대피교범과 기준 제작으로 발전시키며, 인접지역 시설물에 대한 산림 위험 시설에 대한 정책수립의 근거로 삼아야 할 것으로 사료된다.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.70-74
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• 2015

In this paper, satellite communication based video surveillance system that consisted of ultra-small aperture terminals with small-size smart vision sensor is proposed. The events such as forest fire, smoke, intruder movement are detected automatically in field and false alarms are minimized by using intelligent and high-reliable video analysis algorithms. The smart vision sensor is necessary to achieve high-confidence, high hardware endurance, seamless communication and easy maintenance requirements. To satisfy these requirements, real-time digital signal processor, camera module and satellite transceiver are integrated as a smart vision sensor-based ultra-small aperture terminal. Also, high-performance video analysis and image coding algorithms are embedded. The video analysis functions and performances were verified and confirmed practicality through computer simulation and vision sensor prototype test.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.2
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• pp.51-59
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• 2008

While the infrared imaging satellites with the several type were developed and operated in the foreign countries, we do not have the domestic infrared imaging satellite up to now. In the paper, the general characteristics of infrared and the applications of infrared image were introduced. Also the oversea development status of the infrared imaging satellite was surveyed and introduced to this paper. According to foreign status, the infrared image is utilized in various application including the forest fire monitoring, the volcano activity research, sea surface temperature measurement, land surface temperature calculation, the climate change research, and the environment monitoring. According to these trend the development of the domestic infrared imaging satellite in low earth orbit was required.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.345-352
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• 2003

Studies were conducted to find out the justification for levee-burning, customarily executed by farmers for long time, Experiments were carried out in farmers fields with levee-burning early in the season, and some pesticides spraying when necessary from 1995 to 1997. Some data collected are analysed and discussed from several available aspects of surroundings. In relation to some results obtained together with some previous evidences, levee-burning seems to have several adverse effects on levee destruction, partial cause of forest fire, and lowering of spider density in the field during fall, without providing any benefit, while causing no signifant effect on weed flora on levee, insect density in the field, and incidence of the rice-blast. Therefore, concequently, it could be recommend that the levee-burning by farmers should not be continued.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.58-65
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• 2009

A forest fire in the area of power line installations may be caused by flashover disturbances in power systems. In this study, experiments were conducted so as to investigate the reduction in dielectric strength caused by combustion flame, and flashover characteristics in the simulated condition of vertical-type model power lines were examined by making shorter and longer the horizontal distance(s) between combustion flame and high-voltage conductors under the application of 60[Hz] a.c. and d.c. high-voltages. As the results of the experimental investigation it is demonstrated that flame can reduce flashover voltages of the model air-gap in shorter range of the horizontal distance(s). Relative air density is considered in order to analyze the reduction causes of the flashover voltages, and it can be seen that the relative air density has a great influence on the flashover characteristics under the presence of combustion flame.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.187-194
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• 2008

LiDAR는 일반 항공사진 및 위성영상과는 달리 사물의 높이를 측정할 수 있어 산림의 3차원 모델링을 수행할 수 있다. 본 연구에서는 이러한 LiDAR의 특성을 이용하여 산불이 발생한 강원도 양양지역 산림의 물리적 피해를 분석하였으며, 디지털 항공사진으로부터 Normalized Difference Vegetation Index (NDVI)를 추출하여 산림의 생물학적 피해를 분석하였다. 산림의 물리적 피해는 임관의 피해정도에 따라 지표면에서 반사되는 Point Data의 개수의 비율로서 추정을 하였다. 피해정도의 고저(高低)를 구분하는 기준은 통계적 방법 (Jenk's Natural Break) 으로부터 추정된 0.3594을 사용하였으며, 지표면 반사비율이 0.3594 이상인 경우 물리적 피해정도를 고(高, Serious Physical Damage; SPD), 지표면 반사비율이 0.3594 이하인 경우 물리적 피해정도를 저(低, Light Physical Damage; LPD)로 나타내었다. 또한 생물학적 피해는 일반적인 NDVI 값의 범위(-1

• Korean Journal of Remote Sensing
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• v.27 no.3
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• pp.259-276
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• 2011

Short-term land cover changes, such as forest fire scar and crop harvesting, can be detected by high temporal resolution satellite imagery like MODIS and AVHRR. Because these optical satellite images are often obscured by clouds, the static cloud-free composite methods (maximum NDVI, minblue, minVZA, etc.) has been used based on non-overlapping composite period (8-day, 16-day, or a month). Due to relatively long time lag between successive images, these methods are not suitable for observing short-term land cover changes in near-real time. In this study, we suggested a new dynamic cloud-free composite algorithm that uses cut-and-patch method of cloud-masked daily MODIS data using MOD35 products. Because this dynamic composite algorithm generates daily cloud-free MODIS images with the most recent information, it can be used to monitor short-term land cover changes in near-real time. The dynamic composite algorithm also provides information on the date of each pixel used in compositing, thereby makes accurately identify the date of short-term event.