• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.1
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• pp.27-33
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• 2001

SDD(Secchi disk depth) algorithm were composed of SeaWiFS bands combination using in-water optical data sets obtained Lake Sihwa, Kyungki Bay, Chunsu Bay, and Chinhae Bay. SDD algorithm were compared with in-situ data. Reflectance band ratio, $R_{rs}$(490/665) had the highest correlation($R^2$=0.8188) with in-situ data. For in-water algorithm applied to satellite data, reflectance band ratios of Landsat TM data were calculated. However, the results of applied Landsat TM had the low correlation, these reason were discussed in this paper.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.3-8
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• 2008

The purpose of this study is to provide fundamental cooling design data for the large public enclosures as gymnasium. This study executed indoor thermal environment verification of the existing gymnasium by measuring temperature distribution with cooling the space in summer. Cooling loads from human body was not considered. We examined various indoor thermal environment factors of the large enclosed space in this study which include vertical and horizontal temperature distribution, supply and return air flow feature, thermal comfort environment feature, amount of ventilation and etc.

• Fire Science and Engineering
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• v.24 no.5
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• pp.102-106
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• 2010

This paper studied the measurement about the gunpowder residue quantity by using a handgun and we carried out an experiment ignition characteristics of the gunpowder residue for the investigation fire cause into the indoor shooting range in Busan. The measurement of the gunpowder residue quantity is spouted by using a 0.38 inch gun and 9 mm gun. We were carried out evaluation experiments such as impact sensitivity test, static electricity sensitivity test, friction sensitivity test and measuring a flash point for the ignition characteristics about the gunpowder residue. From experiment results, the impact sensitivity and friction sensitivity of the gunpowder residue in comparison with ball powder are highly sensitive and the gunpowder residue ignites at a relatively low temperature.

• The Journal of the Acoustical Society of Korea
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• v.14 no.6
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• pp.48-53
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• 1995

A considerable number of methods are available for predicting traffic noise levels of road networks where sound is freely propagating. But surrounding buildings reflect back sound to the road and sound energy is increased by these reflectors. Therefore, this study was focussed on the establishment of the prediction method of road traffic noise under reflective conditions. This prediction method was developed by establishing prediction formulas of noise level such as $L_{10},\;L_{50},\;L_{90}\;and\;L_{eq}$. The sound energy density was employed to establish prediction formulas in terms of independent variables. The validity of the proposed prediction formulas was been confirmed by applying them to actually measured parameters of road traffic noise and noise level data. On the whole, the agreement between measured and predicted noise levels appeared to be satisfactory. The conclusion might be reached that the method developed in this study could be used to predict road traffic noise under reflective conditions.

• Journal of the Korean GEO-environmental Society
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• v.2 no.2
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• pp.23-32
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• 2001

A soil wall reinforced by soil nailing is excavated in the typical soil conditions which are consisted of weathered soil, weathered rock and soft rock. The resulting nail loads computed are compared to loads measured by utilizing strain gauges during construction. The wall deflection at two locations are related to construction events and specific soil conditions, providing an understanding of the behavior of soil nailed walls. The load distribution along the nail indicated relatively high loads close to the wall. The mobilized load on the nail is proportional to the wall deflection showing the maximum value at the surface of the wall. The construction monitoring for this project provided valuable information in understanding the behavior of soil nailed walls.

• Journal of the Korean Geotechnical Society
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• v.20 no.3
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• pp.67-74
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• 2004

A case study was performed to verify the applicability of existing formulae for predicting bridge scour in cases where its piers are founded in fine-grained soils. The object of study was the Kanghwa Choji Bridge area where the streambed consists of mainly clayey soil. Site investigation included: direct measurement of scour depths around piers using an ultrasonic probe; and collection of undisturbed soil samples which were later used to determine geotechnical properties and scour rate under different stream velocities. Scour depth prediction was made by employing several conventional methods and compared with the measured value. All methods, not taking soil's intrinsic property against erosion into consideration, overestimated scour depth by a factor of 3.6 to 6.5. On the other hand, the SRICOS method yielded a reasonably acceptable overestimation by a factor of 1.7.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.59-65
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• 2007

This study is to propose the basic data for deciding remodeling of wornout educational facilities. In order of it, the indoor environmental standard, the actual conditions of thermal environment and sound insulation of walls were examined through field measurement in the subjected open elementary school(J school) and modernization model of elementary school(Y school) which they are located in Seoul. As the result, standard for indoor environmental factors of educational facilities which is established by Ministry of Education is not subdivided into indoor environmental performances considering usages and characteristics of classrooms for comfortable indoor environment. The vertical temperature difference in general classroom and in open classroom showed to be $11.2^{\circ}C$ and $12.1^{\circ}C$ respectively, while indoor temperature of special classroon was, on the whole, higher than that of any other classroom due to its specific heat flux of wall materials. The sound insulation performance of the masonry brick wall of classroom satisfied the minimum standard of AIJ, Architectural Institute of Japan, in the open elementary school and the modernization model of elementary school. That is to say, the movable partition wall between the classroom and the corridor disturbed students in their class in the open school.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.5
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• pp.1085-1092
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• 2010

This paper describes the development of estimating equation for under 16 aged children's exposure to habitat's magnetic field for 24 hours by using particle swarm optimization(PSO) algorithm, which was carried out by using the measured database collected from the exposure survey to Korean habitat's magnetic field as to under 16 aged Korean students such as preschooler, children in elementary school, and children in middle school. Sex, age, residence type, size of habitation site, distance from power line, and power transmission voltage are used as the input data of estimating 24 hour's personal exposure to magnetic field. And distribution of 24 hour's personal exposure to magnetic field, exposure characteristic to magnetic field, and exposure characteristic to magnetic field according to special conditions, are analyzed for under 16 aged children.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.369-373
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• 2015

본 연구에서는 낙동강 강정고령보에서 달성보 구간에 대한 지속적 지형조사를 통해 다기능보 건설 및 운영으로 인한 하천지형의 변화양상과 정도를 파악하고자 하였다. 이를 위하여 4대강살리기사업 이전의 측량성과(낙동강하천기본계획, 2009년)를 기준으로 보 건설 및 하도정비 이후인 2013년과 2015년에 실측한 지형자료와 비교하였다. 2013년과 2015년 지형자료 취득은 대상구간(강정고령보~달성보: 23 km) 내 하도와 홍수터에 대해 각각 단일 및 다중빔 음향측심기와RTK-GPS 등의 측량장비를 이용하여 40 m 이상의 평면공간해상도를 가지도록 수행하였다. 대상구간 내 하천기본계획 지정 횡단측선에 대해 2013년과 2015년 지형정보를 비교함으로써 보 건설 및 하도정비로 인한 지형변화양상과 정도를 파악하고자 하였다. 특정 측선에서의 횡단지형자료인 2009년 측량성과와 비교하여 2013년과 2015년 실측자료는 전체 대상구간에 대한 3차원 공간정보를 제공함으로써 이들 간의 정성, 정량적 비교를 통하여 보 건설 및 운영을 통한 하도내 국부적 지형변화의 정도와 양상을 파악할 수 있었다. 이를 통해 하천의 지형학적, 수리학적 특성뿐만 아니라 보 건설 및 하도정비 등의 물리적 여건변화에 따른 특정 하천구간에 대한 시 공간적 지형변화특성을 파악할 수 있었으며, 이는 향후 하천관리 및 설계를 위한 연구와 실무에 널리 활용될 수 있을 것으로 기대된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.168-168
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• 2021

기후변화로 인한 태풍과 국지성 집중호우의 발생 증가로 국토의 64%가 산으로 이루어진 우리나라에서 산사태와 토석류와 같은 산지 재해가 빈번하게 발생하고 있다. 토석류는 물과 흙, 자갈, 유목 등이 계곡을 따라 이동하여 하류 지역에 위치한 주거 및 공공시설, 도로, 하천 그리고 인명에 피해를 입히는 자연재해이다. 본 연구대상 지역인 강원도 삼척시를 기준으로 2019년 10월에 발생한 태풍 '미탁'은 시간당 최대 110mm/hr, 누적강수량 487mm를 기록하였으며, 태풍으로 인한 강풍, 폭우, 홍수뿐만 아니라 산사태, 토석류와 같은 산지 재해로 사망 13명, 실종 2명, 이재민 910세대 1,442명의 인명 피해와 공공시설 1,835건, 사유시설 3,700건 등의 재산피해를 발생시켰다. 연구대상 지역에 높이 2m의 기설치된 저감시설이 있었으나 당시의 토석류 발생량을 저감하기에 규모가 작아 주택, 도로와 주민들이 있는 하류 지역에 많은 피해가 발생하였다. 따라서 본 연구에서는 토석류 피해가 발생한 강원도 삼척시 원덕읍 지역을 대상으로 현장조사를 통해 획득한 실측 자료를 활용하여 Hyper KANAKO 모형의 입력 매개변수로 사용하였다. 실측 자료를 모형에 적용하여 최대 유동심과 유속이 발생한 지점을 분석한 후 기설치된 재해 저감시설과 동일한 제원의 재해 저감시설을 설치하였을 때와 재해 저감시설의 높이와 종류를 변경하였을 때를 비교·분석하였다.