• 생태와환경
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• 제46권3호
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• pp.319-331
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• 2013

Recent climate change, which is mostly ascribed to anthropogenic activities, is believed to be a major factor leading to biodiversity decreases and ecosystem service deteriorations. I have reviewed recent studies on climate change effects for many ecological processes involved with plants, in order to improve our understanding of the nature of ecological complexity. Plants in general have better growth and productivity under high levels of $CO_2$, although the long term effects of such $CO_2$ fertilizers are still controversial. Over the last 30 years, the Earth has been greening, particularly at higher latitudes of the Northern Hemisphere, perhaps due to a relaxation of climatic constraints. Human appropriation of net primary productivity (NPP), which corresponds up to 1/3 of global NPP, is ultimately responsible for climate change and biodiversity decreases. Climate change causes phenological variations in plants, especially in regards to spring flowering and fall leaf coloring. Many plants migrate polewards and towards higher altitudes to seek more appropriate climates. On the other hand, tree mortality and population declines have recently been reported in many continents. Landscape disturbance not only hinders the plant migration, but also makes it difficult to predict the plants' potential habitats. Plant and animal population declines, as well as local extinctions, are largely due to the disruption of species interactions through temporal mismatching. Temperature and $CO_2$ increase rates in Korea are higher than global means. The degree of landscape disturbances is also relatively high. Furthermore, long-term data on individual species responses and species interactions are lacking or quite limited in Korea. This review emphasizes the complex nature of species responses to climate change at both global and local scales. In order to keep pace with the direction and speed of climate change, it is urgently necessary to observe and analyze the patterns of phenology, migration, and trophic interactions of plants and animals in Korea's landscape.

• 한국의류학회지
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• 제28권2호
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• pp.292-302
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• 2004

The purpose of this study was to evaluate thermal properties of lab gowns developed from the point of safety and work efficiency. We evaluated thermal and subjective responses of subjects wearing functional new lab gowns (Type B, C, D) and a popular lab gown on the market (Type A). Type B was a new lab gown made of woven fabric with functional cuffs. Type C was a new apron made of woven fabric with arm protectors. Type D was a new lab gown made of non-woven material with functional cuffs and openings around the armpits. Temperature in the climatic chamber was set at 19$^{\circ}$C as an indoor temperature in winter and at 24$^{\circ}$C in summer. There were no significant differences in rectal temperature and heart rate among four types of gowns and between two air temperatures for 120 min. Mean skin temperature was much higher in the type A and B than in He type C and D (p .05). In the 19$^{\circ}$C air, clothing microclimate temperature on the back was the highest in the type B and was the lowest in the type C (p .05). Clothing microclimate humidity was not significant differences among gowns. In subjective .esponses, subjects perceived that Type B was the warmest gown in the 19$^{\circ}$C and the hottest and more humid in the 24$^{\circ}$C than other gowns. Inversely, type C was the coolest gown among four gowns. Both in the 19$^{\circ}$C and in the 24$^{\circ}$C, the Type D had gained most responses of being comfortable. In conclusion, the temperature difference of 5$^{\circ}$C was more of an influencing factor than the difference from four types of lab gowns. Secondly, we recommend the manufacturers to make lab gowns with functional cuffs for safety purposes. Thirdly, the spread of the type of apron with arm protector will contribute to increase of the frequency of wearing in summer. Fourthly, it is necessary to study continuously about lab gowns with non-woven materials for researchers exposed to toxic chemical and biological materials.

• 대한공간정보학회지
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• 제18권4호
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• pp.79-86
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• 2010

본 연구는 태양광 에너지 발전 시설의 효율 증대와 입지 선정을 위한 태양광 역추적에 관한 연구이다. 기후 및 지형요소들을 가지고 소규모 지역의 태양광을 역추적 하는데 목적을 두고 있다. 6가지 기후요소들에 대해 상관 분석을 수행, 상관계수 및 유의확률을 확인하여 상관관계가 없다고 판단된 풍속과 구름의 양은 제외하였다. 나머지 기후요소 및 지형요소를 가지고 각각 회귀분석을 수행해본 결과, 일사량에 가장 큰 영향을 끼치는 요소로는 일조량과 지형의 고도였다. 이 결과를 바탕으로 정확한 일사량 모델링을 위해 기후 및 지형요소를 가지고 일사량 모델링을 수행한 결과, 기후요소가 지형요소에 비해 더 큰 계수 값을 가졌다. 이는 기후요소가 지형요소에 비해 더 큰 영향력을 가진다는 것을 의미한다.

• 설비공학논문집
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• 제27권9호
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• pp.455-462
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• 2015

Residential buildings account for a significant portion of the total building-energy usage in Korea, and a variety of research studies on the domestic boiler have therefore been carried out; however, most of these studies examined the boiler itself, whereby the part-load ratio characteristics and the corresponding gas-energy consumption patterns were not analyzed. In this study, the part-load ratio and operating characteristics of a domestic gas boiler were analyzed within a residential building equipped with a radiant floor-heating system; in addition, the energy consumption between condensing and conventional boilers was comparatively analyzed. Our results show that significant portions of the total operating hours, heating load, and energy consumption are in the part-load ratio range of 0 through 40%, whereby the energy consumption was significantly affected by the boiler efficiency under low part-load conditions. These results indicate that the part-load operation of a boiler is an important factor in residential buildings; furthermore, replacing a conventional boiler with a condensing boiler can reduce annual gas-energy usage by more than 20%.

• 한국농공학회논문집
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• 제59권6호
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• pp.1-8
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• 2017

The purpose of this study was to provide basic data for development of environmental design technology for greenhouses constructed in reclaimed lands. We analyzed the climatic conditions around seven major reclaimed land areas in Korea, which have a plan to install advanced horticultural complexes. The characteristics of heating load through the thermal environment measurement of the greenhouse in Saemangeum were analyzed. The part to be applied to the environmental design of the greenhouses in reclaimed lands were reviewed. The overall heat transfer coefficient of the experimental greenhouse with the aluminum screen and multi-layer thermal curtain averaged $3.79W/m^2^{\circ}C$. It represents a 44 % heat savings rate compared with plastic greenhouses with a single covering, which was significantly lower than that of the common greenhouses with 2-layer thermal curtains. This is because the experimental greenhouse was installed on reclaimed land and wind was stronger than the inland area. Among the total heating load, the transmission heat loss accounted for 96.4~99.9 %, and the infiltration loss and the ground heat exchange were low. Therefore, it is necessary to take countermeasures to minimize the transmission heat loss for greenhouses constructed in reclaimed lands. As the reclaimed land is located on the seaside, the wind is stronger than the inland area, and the fog is frequent. Especially, Saemangeum area has 2.6 times stronger wind speed and 3.4 times longer fog duration than the inland area. In designing the heating systems for greenhouses in reclaimed lands, it is considered that the maximum heating load should be calculated by applying the wind coefficient larger than the inland area. It is reasonable to estimate the operation cost of the heating system by applying the adjustment factor 10 % larger than the average in calculating the seasonal heating load.

• 한국산림과학회지
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• 제25권1호
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• pp.1-12
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• 1975

남한지역(南韓地域)에 있어서 80개소(個所)의 기상측정치(氣象測定値)를 기초로 하여 각지점(各地點)의 온도지수(溫度指數)와 한랭지수(寒冷指數)를 계산(計算)하고 이것을 도상(圖上)에 나타내었으며 등지선(等指線)을 추적(追跡)하여서 작도(作圖)하였다. 이때 30년간(年間)의 기상인자(氣象因子)를 평균(平均)하였다. 현재(現在) 일반적(一般的)으로 우리가 시인(是認)하고 있는 삼림대(森林帶)의 경계(境界)는 온량지수(溫量指數)보다는 한랭지수(寒冷指數)의 등지선(等指線)과 더 관련(關聯)이 있는 것으로 해석된다. 몇 조림수종(造林樹種)에 대한 온량지수(溫量指數)에 대(對)한 검토를 했다. 이와같은 내용은 생물기후(生物氣候), 재배가능지(栽培可能地)의 추측(推測) 생태(生態)등의 사실(事實)을 설명하는데 도움이 될 자료(資料)가 될 것으로 생각된다.

• 대한원격탐사학회지
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• 제22권5호
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• pp.313-323
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• 2006

Forest Canopy Density is a dynamic process mediated by various natural and anthropogenic factors. It can be changed over time and locations in the same forest type and landscape. However, human dimensions are considered as the primary force of landscape change and subsequent forest canopy loss in tropical regions of the world. Many studies have been indicated that roads have a far greater impact on forests than simply allowing access for human use. Similarly, rivers have been used as means of transportation, hence illegal logging and felling further deplete forest canopy density. The main objective of this study was to investigate the spatio-temporal dynamic alterations of Forest Canopy Density (FCD) across with site associated factors such as biophysical, physical and human interferences in tropical region of Nepal from 1988 to 2001. Landsat TM and ETM+ of 1988 and 2001 were used to assess the spatial and temporal dynamic alterations of FCD. This analysis revealed that distance to human settlements at P=<0.01, rivers, human interferences (path and fire) and species composition had a statistically significance at P=<0.05 level. However, other factors did not show any significant relation. So, we concluded that understanding of dynamic alterations of FCD with respect to factors was quite complex phenomena. Other surrounding environment could also playa significant role. A comprehensive analysis could be required to understand such complexities. Therefore, additional factors such as climatic, biophysical, social, and institutional with respect to spatio-temporal variability should be considered for the better understanding of canopy dynamic.

• 한국기후변화학회지
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• 제9권3호
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• pp.223-234
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• 2018

Estimation of future land cover based on climate change scenarios is an important factor in climate change impact assessment and adaptation policy. This study estimated future land cover considering Shared Socioeconomic Pathways (SSP) using Scenario Generators. Based on the storylines of SSP1-3, future population and estimated urban area were adopted for the transition matrix, which contains land cover change trends of each land cover class. In addition, limits of land cover change and proximity were applied as spatial data. According to the estimated land cover maps from SSP1-3 in 2030, 2050, and 2100, respectively, urban areas near a road were expanded, but agricultural areas and forests were gradually decreased. More drastic urban expansion was seen in SSP3 compared to SSP1 and SSP2. These trends are similar with previous research with regard to storyline, but the spatial results were different. Future land cover can be easily adjusted based on this approach, if econometric forecasts for each land cover class added. However, this requires determination of econometric forecasts for each land cover class.

• Journal of Species Research
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• 제10권3호
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• pp.246-254
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• 2021

Subalpine and alpine ecosystems are especially vulnerable to temperature increases. Betula ermanii Cham. (Betulaceae) is a dominant broad-leaved tree species in the subalpine zone and is designated as a 'Climate-sensitive Biological Indicator Species' in South Korea. This study aimed to predict the potential distribution of B. ermanii under current and future climate conditions in South Korea using the MaxEnt model. The species distribution models showed an excellent fit (AUC=0.99). Among the climatic variables, the most critical factors shaping B. ermanii distribution were identified as the maximum temperature of warmest month (Bio5; 64.8%) and annual mean temperature (Bio1; 20.3%). Current potential habitats were predicted in the Baekdudaegan mountain range and Mt. Hallasan, and the area of suitable habitat was 1531.52 km², covering 1.57% of the Korean Peninsula. With global warming, future climate scenarios have predicted a decrease in the suitable habitats for B. ermanii. Under RCP8.5-2070s, in particular, habitat with high potential was predicted only in several small areas in Gangwon-do, and the total area suitable for the species decreased by up to 97.3% compared to the current range. We conclude that the dominant factor affecting the distribution of B. ermanii is temperature and that future temperature rises will increase the vulnerability of this species.

• 한국컴퓨터정보학회논문지
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• 제14권10호
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• pp.207-215
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• 2009

최근 도시화 율이 증가됨에 따라 발생되는 도시의 범죄 예방을 위하여 컴퓨터정보기술과 GIS 기술을 이용한 범죄 공간의 분석에 대한 연구가 활발하게 이루어지고 있다. 본 논문에서는 정적인 환경에서 도시공간정보에 포함된 지역특성을 이용하여 단위 셀별 우범 위험도를 계량화하여 래스터 형태의 확률 지도를 구성하였다. 지형적 특성에 의한 상대적 위험도, 시설물에 의한 상대적 위험도, 수목이나 하천에 의한 위험도 등을 기본으로 하여 위험도 확률 지도를 구축한다. 이를 통합한 위험도 확률 지도를 구할 때는 각각의 단위 위험도에 기후나 계절적 요인에 의해 가중치를 적용한 후 평균하게 된다. 또한 일회성 분석이 아닌 범죄 발생 상대적 위험지수의 패턴을 판독키로 하여 전체 위험도의 확률 지도를 생성하여 이후 발생하는 범죄의 유형을 계량화하는 확률지도에 추가적으로 적용하어 정적인 정보가 아닌 시간의 흐름에 따라 범죄 위험도 확률지도가 달라질 수 있는 모델과 시뮬레이션 하는 방법론을 제안하였다.