• 한국환경복원기술학회지
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• 제23권1호
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• pp.89-96
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• 2020

Adverse impact of Particulate Matters(PM10, PM2.5; PMs) significantly affects daily lives. Major countermeasures for reducing concentration of PMs were focused on emission source without considering spatial difference of PMs concentration. Thus, this study analyzed spatial·temporal distribution of PMs with observation data as well as potential contributing factors on PMs concentration. The annual average concentration of PMs have been decreased while the particulate matter warnings and alerts were significantly increased in 2018. The average concentration of PMs in spring and winter was higher than the other seasons. Also, the spatial distribution of PMs were also showed seasonality while concentration of PMs were higher in Seoul-metropolitan areas in all seasons. Climate variables, emission source, spatial structure and potential PM sinks were selected major factors which could affects on ambient concentrations of PMs. This paper suggest that countermeasures for mitigating PM concentration should consider characteristics of area. Climatic variables(temperature, pressure, wind speed etc.) affects concentrations of PMs. The effects of spatial structure of cities(terrain, ventilation corridor) and biological sinks(green infrastructure, urban forests) on concentration of PMs should be analyzed in further studies. Also, seasonality of PMs concentration should be considered for establishing effective countermeasures to reduce ambient PMs concentration.

• Entomological Research
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• 제48권6호
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• pp.540-549
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• 2018

Climate change due to global warming and changes in land use increase the development time and distribution, as well as the abundance, of mosquitoes, thereby negatively affecting human life and health. In this study, we investigated the habitat characteristics of mosquito occurrence sites in Danwon-gu, Ansan city, Korea, based on a daily record of civil pest complaints lodged at the Danwon-gu Community Health Center. We considered two types of factors (natural and artificial) known to affect mosquito occurrence. We confirmed a total of 554 cases of mosquito occurrence from March 2014 to August 2017. The total study area was $49.11km^2$, with urban areas constituting the largest proportion. Additionally, we investigated habitat preferences of mosquitoes in terms of terrain factors; generally, mosquitoes occurred at low elevations and on low slopes. Regarding the preference of oviposition sites, mosquitoes occurred at higher rates near streams and crops lands. The rate of mosquito occurrence tended to increase in areas with dense human populations. Regarding climatic factors, the rate of mosquito occurrence increased in areas with high temperature and low precipitation.

• Wind and Structures
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• 제37권2호
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• pp.95-104
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• 2023

The latest revision of AS/NZS 1170.2 incorporates some new research and knowledge on strong winds, climate change, and shape factors for new structures of interest such as solar panels. Unlike most other jurisdictions, Australia and New Zealand covers a vast area of land, a latitude range from 11° to 47°S climatic zones from tropical to cold temperate, and virtually every type of extreme wind event. The latter includes gales from synoptic-scale depressions, severe convectively-driven downdrafts from thunderstorms, tropical cyclones, downslope winds, and tornadoes. All except tornadoes are now covered within AS/NZS 1170.2. The paper describes the main features of the 2021 edition with emphasis on the new content, including the changes in the regional boundaries, regional wind speeds, terrain-height, topographic and direction multipliers. A new 'climate change multiplier' has been included, and the gust and turbulence profiles for over-water winds have been revised. Amongst the changes to the provisions for shape factors, values are provided for ground-mounted solar panels, and new data are provided for curved roofs. New methods have been given for dynamic response factors for poles and masts, and advice given for acceleration calculations for high-rise buildings and other dynamically wind-sensitive structures.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.199-206
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• 2001

Landslides generally occur due to influences of the internal and external factors. Internal factors include ground characteristics, terrain and so on. External factors can also be divided into natural factors such as rainfall, ground water, earthquake and so on, and artificial factors resulting from cutting and embankments. Among these factors, rainfall becomes the most important external factors by means of which landslides occur in Korea. To appropriately deal with tile effects of pore water pressures due to rainfall, the method using the pore water pressure ratio(r$\_$u/) is generally applied in slope stability analysis or the design of slope reinforcements. Since tire value of r,, is in general not constant over the whole cross section, in most slope stability analyses the average values are used with little loss in accuracy. However, determination of the average values of r$\_$u/ to applied in the design is difficult problem. Therefore, in this study, tile average values of r$\_$u/ according to the intensity of rainfall and slope inclination is suggested based on results of the small scaled model tests using the artificial rainfall apparatus. It is found from the model tests that the average values of r$\_$u/ is about 0.07∼0.18(in case of the intensity of rainfall is 50mm/hr.), about 0.10∼0.28(in case of the intensity of rainfall is 100mm/hr.), and about 0.10∼0.33(in case of the intensity of rainfall is 150mm/hr.).

• 한국콘텐츠학회논문지
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• 제11권4호
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• pp.440-447
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• 2011

적지선정은 이용목적에 적합한 공간 또는 속성조건을 인자로 정하고 이를 만족하는 지역을 선정하는 것으로 체계적으로 수행되어야 한다. 본 연구는 계층적 분석과정과 GIS분석 모델링 방법을 이용하여 주거지 개발의 합리적인 적지선정을 시도한 것이다. 연구에서 적지선정을 위해 공간적 속성적 분석방법을 계층화하였으며 단계 별 효율적 결과도출을 위해 GIS분석 모델을 사용하였다. 다음 단계로, 적지선정 조건과 의사결정요소들을 유기적으로 고려하여 정량적 정성적인 평가지표를 만들고 요소들의 경중에 따라 가중치를 적용하였다. 특히, 주관적 평가요소인 경관에 대한 심미적인 요소를 반영하기 위해 3차원 지형모델의 시뮬레이션기법을 사용하였으며 계층적기법을 도입한 정성적인 평가요소로 고려하였다. 연구결과, 계층적 GIS모델분석으로 신속, 정확하게 복합적인 요구조건을 만족하는 적지를 선정할 수 있었다.

• 한국멀티미디어학회논문지
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• 제13권2호
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• pp.298-307
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• 2010

게임이나 실시간 시뮬레이션 시스템과 같은 분야에서 잔디는 광범위한 지표면을 구성하는 중요한 요소 중 하나이다. 실제 넓은 지형에 자라나는 많은 수의 잔디를 효율적으로 렌더링 하는 작업은 결코 쉬운 일이 아니다. 이러한 문제를 해결하려면 모델의 질과 계산 비용 절약의 두 가지 문제에 늘 직면하게 된다. 본 논문에서는 이러한 두 가지 문제를 해결하기 위한 방안으로 프랙탈 이론과 인스턴싱 기법을 도입하여 자연스러운 잔디의 효율적인 표현 방법을 제안한다. 기존의 잔디 표현의 경우 동일한 모델을 반복적으로 적용하였지만 본 연구에서는 프랙탈의 자기 유사성의 기본 이론을 활용하되 지형의 성질과 빛의 양을 인자로 도입하여 조건에 맞는 다양한 잔디의 자연스러운 표현 방법을 설계하고 또한 많은 수의 잔디 모델을 실시간으로 렌더링하기 위하여 GPU를 활용한 셰이더 인스턴싱 기법을 적용한다.

• 한국환경과학회지
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• 제21권4호
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• pp.517-533
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• 2012

This study calculated wind speed at the height of 10 m using a disaster prediction model(Florida Public Hurricane Loss Model, FPHLM) that was developed and used in the United States. Using its distributions, a usable information of surface wind was produced for the purpose of disaster prevention when the typhoon attack. The advanced research version of the WRF (Weather Research and Forecasting) was used in this study, and two domains focusing on South Korea were determined through two-way nesting. A horizontal time series and vertical profile analysis were carried out to examine whether the model provided a resonable simulation, and the meteorological factors, including potential temperature, generally showed the similar distribution with observational data. We determined through comparison of observations that data taken at 700 hPa and used as input data to calculate wind speed at the height of 10 m for the actual terrain was suitable for the simulation. Using these results, the wind speed at the height of 10 m for the actual terrain was calculated and its distributions were shown. Thus, a stronger wind occurred in coastal areas compared to inland areas showing that coastal areas are more vulnerable to strong winds.

• Journal of the korean society of oceanography
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• 제37권3호
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• pp.169-177
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• 2002

An eddy-resolving free-surface primitive-equation model with nonlinear terrain-following coordinates is established to study the exchange of water masses among the Asian marginal seas and their adjacent waters. A curvilinear coordinate system is used to generate the horizontal grid with a variable resolution for the regional oceans from $5^{\circ}$S to $45^{\circ}$N and $100^{\circ}$E to $155^{\circ}$E. The higher resolution region has about a 10 km by 10 km grid covering the complex geometry of the coastal marginal seas, while the lower resolution region has about a 30 km by 30 km grid covering the eastern Pacific. The model is initialized by the Levitus annual climitology and forced by the monthly mean air-sea fluxes of momentum, heat, and freshwater derived from the Comprehensive Ocean-Atmosphere Data Set. High-resolution and low-viscosity are identified as the key factors for a better representation of the exchange of waters through narrow straits and passages between the marginal seas and their adjacent waters. The dynamics of the loop currents and eddies in the South China Sea and Celebes Sea are examined in detail. It has found that the anticyclonic loop and detached eddies from the Kuroshio through the Luzon Strait play an important role in transporting warm and salty water into the South China Sea, while the cyclonic circulation of the Mindanao Current in the Celebes Sea plays a role in contributing cold water to the Indonesian throughflow. The deep undercurrent of the western Pacific is shown to provide fresher water to the South China Sea and Celebes Sea. These modeling results suggest that the exchange processes via the narrow straits and passages are of fundamental importance to the maintenance of water masses for the marginal sea region.

• 한국화재소방학회논문지
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• 제13권1호
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• pp.31-36
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• 1999

1996년 4월 23일 강원도 고성군에서 발생한 산불에 대한 현장조사와 주요수목인 굴참나무와 소나무에 대한 열량에 대한 실험을 하였다. 산불의 확산에 영향을 주는 주된 요인은 크게 기상, 연료, 지형 3가지로 구분할 수 있는 데 기상 조건에서는 산불위험경보 수준이었고, 연료 조건에서는 높은 열량값을 가지고 이쓴 소나무 순림이 전체 산림의 63%를 차지하고 있었다. 산림의 지형에서는 지형의 변화와 기복이 크며 단순상향사면형의 지형이 어우러진 골짜기 형태로 급경사지가 대부분이었다. 주요 수목인 소나무와 굴참나무의 열량 실험에 대한 분석 결과는 소나무의 경우 부위별 전체 열량값이 13.43kcal/g, 굴참나무는 9.46kcal/g로 나타났다. 열분해에 의한 질량손실의 경우 소나무가 굴참나무보다 약 35.71~10.05% 더 높은 질량 손실률을 나타냈다. 따라서 소나무가 굴참나무보다 열에 대한 저항성이 낮다고 볼 수 있다.

• 자원환경지질
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• 제13권4호
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• pp.215-227
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• 1980

The rock units of Goesan area in the Ogcheon metamor phic terrain established on the basis of field criteria should be redefined into following sequence. Based on shear senses in secondary small structures which are usually observable in the investigated area, the stratigraphy can be lithologically divided into the lower pelite, pebbly mudstone, upper pelite, quartzite and psammite unit in ascending order. This conclusion is in discordance with a previous opinion; Munjuri formation and Guryongsan formation may be equivalent to upper pelite unit, Iwonri formation and Hwanggangri formation to pebbly mudstone. From this, it may be inferred that isoclinal overturned folds repeatly occur in the area. The uranium bearing coaly thin layers in upper pelite unit have relatively broad exposures in Deogpyeongri block of Goesan area along culmination zone in the central part of the investigated area. It is believed that structural feature in the block recognized complexly refolded synform plunging to southwest. Mineralogical and radiometric studies were made on 135 representative samples from the Ogcheon Group of Korea. The mineralogy of all black slate samples is qualitatively similar but quantitatively ·different. The uranium distribution in the studied area show approximately log normal. Uranium in the black slates of the Ogcheon Group was deposited together under same physico-chemical environmental conditions. The chemical and geological factors that controlled the abundance of organic carbon and iron oxides also controlled the uranium content. The relationship of the major components to uranium can be expressed by the following regression equation: $Log(U\times10^4+1)$= 1.70999-0.00367(quartz)0.00512(micas)-0.00930 (other silicates)+0.01911 (iron oxides)-0.03389(other opaques)+0.02062(organic carbon).