여름철 도시근린공원의 기온저감 효과 - 경기도 수원시 효원공원 -

박수국 ( Sookuk Park ),조상만 ( Sangman Jo ),현철지 ( Cheolji Hyun ),공학양 ( Hak-yang Kong ),김승현 ( Seunghyun Kim ),신영규 ( Youngkyu Shin ) 한국환경과학회 2017 한국환경과학회지 Vol.26 No.9

In order to investigate the effect of air temperature reduction on an urban neighborhood park, air temperature data from five inside locations (forest, pine tree, lawn, brick and pergola) depending on surface types and three outside locations (Suwon, Maetan and Kwonsun) depending on urban forms were collected during the summer 2016 and compared. The forest location had the lowest mean air temperature amongst all locations sampled, though the mean difference between this and the other four locations in the park was relatively small (0.2-0.5℃). In the daytime, the greatest mean difference between the forest location and the two locations exposed to direct beam solar radiation (brick and lawn) was 0.5-0.8℃ (Max. 1.6-2.1℃). In the nighttime, the mean difference between the forest location and the other four locations in the park was small, though differences between the forest location and locations with grass cover (pine tree and lawn) reached a maximum of 0.9-1.7℃. Comparing air temperature between sunny and shaded locations, the shaded locations showed a maximum of 1.5℃ lower temperature in the daytime and 0.7℃ higher in the nighttime. Comparing the air temperature of the forest location with those of the residential (Kwonsun) and apartment (Maetan) locations, the mean air temperature difference was 0.8-1.0℃, higher than those measured between the forest location and the other park locations. The temperatures measured in the forest location were mean 0.9-1.3℃ (Max. 2.0-3.9℃) lower in the daytime than for the residential and apartment locations and mean 0.4-1.0℃ (Max. 1.3-3.1℃) lower in the nighttime. During the hottest period of each month, the difference was greater than the mean monthly differences, with temperatures in the residential and apartment locations mean 1.0-1.6℃ higher than those measured in the forest location. The effect of air temperature reduction on sampling locations within the park and a relatively high thermal environment on the urban sampling locations was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with a high sky view factor and surface types with high evapotranspiration potential (e.g. grass) showed the maximum air temperature reduction. In the urban areas outside the park, the low-rise building area, with a high sky view factor, showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, while in the nighttime the area with high-rise buildings, and hence a low sky view factor, showed high air temperature due to the effect of terrestrial (longwave) radiation emitted by surrounding high-rise building surfaces. The effect of air temperature reduction on the park with a high thermal environment in the city was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with high sky view factor and surface types (e.g., grass) with evapotranspiration effect showed maximum air temperature reduction. In the urban areas outside the park, the high sky view factor area (low-rise building area) showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, but in the nighttime the low sky view factor area (high-rise building area) showed high air temperature due to the effect of terrestrial (longwave) radiation emitted surrounding high-rise building surfaces.

옥상녹화 재료에 따른 실내온도 저감효과에 관한 연구

박세영,송태갑,김은일 전북대학교 부설 휴양및경관계획연구소 2012 휴양및경관연구 (J East Asian Landscape Studies) Vol.6 No.1

본 연구는 옥상녹화의 재료에 따라 실내온도 저감효과를 검토하여 에너지 절약을 위한 최적의 옥상녹화 재료를 선정하는데 목적이 있다.실험은 사방 1m의 실험구를 10mm 방수합판으로 제작하고 상부에 물, 잔디, 관목 그리고 비교대상인 재료를 채우지않은 빈상자 등 총 4개의 실험구와 실험구 양쪽의 외부 영향을 차단하려는 목적의 빈상자 등 총 6개의 동일 규격의실험구를 준비하였다.실험은 외부기온 30도 이상인 7일간의 실외와 실내온도를 측정하여 비교하였다. 시간은 아침 9시부터 오후 6시까지시간별로 실외온도와 실내온도를 측정하였고 그 가운데 온도차가 많은 12시부터 오후 5시까지의 데이터를 실내온도에서 실외온도를 뺀 값으로 온도저감효과를 검토하였다.그 결과, 잔디가 온도저감효과가 가장 높은 것으로 나타났고 그 다음으로 관목, 수경, 빈방 순으로 나타났다. 또한,외부 온도가 낮을수록 온도저감효과는 떨어졌으며 경우에 따라서는 오후 5시 이후에 빈방이 일반재료의 실험구 실내온도보다더 떨어지는 현상이 나타나 옥상녹화를 함으로써 실내온도의 급격한 변화를 줄일 수 있음을 알 수 있었다. 옥상녹화를하지 않은 실험구에서 외부온도에 따라 실내온도가 영향을 가장 많이 받았다. This study is to select the optimal green roof materials for energy-saving by investigating their reducing effects on room temperature according to the rooftop materials. For the experiment, 6 1m square boxes were made of waterproof plywood 10mm thick. The tops of three boxes were filled with water, grass, or shrubs respectively and one box was used as a control subject without any fill materials. The two remaining boxes were placed on the each side of the 4 boxes to protect from outside influence on the experiment. In the experiment, ambient and room temperatures had been measured for 7 days when the outside temperature was more than 30 degrees. Each temperature was measured from 9:00 a.m. to 18:00 p.m. hourly, and only data taken from 12:00 to 17:00, when the temperature difference between outside and room temperature is relatively large, were used to investigate the effect of temperature reduction. The result of the study shows that grass has the highest effect on temperature reduction, shrubs and hydroponics are next. In addition, it shows that the lower the outside temperature is, the less the reduction effect is. In some cases, the room temperature of an empty room dropped more than that of the experimental groups after 5:00 p.m., which means green roofs can prevent the rapid change of room temperature. Finally, the experimental box without green roof was the most affected by the ambient temperature.

Effects of Roads Characteristics and Green Space on Urban Temperature

Cho Hye Jin 한국도로학회 2020 한국도로학회논문집 Vol.22 No.6

PURPOSES : The purpose of this study is to investigate the effects of urban road characteristics on temperature changes in urban areas using surface thermal temperature. METHODS : This study measured the surface thermal temperature of each road component from urban roads, analyzed the effect of the road component characteristics and vegetation on temperature, and estimated the regression models. RESULTS : As a result, the mean temperature was 27.3 ℃ on the roadway, 25.5 ℃ on the vegetated median, and 22.9 ℃ on the sidewalks. The roadside temperature was 26.14 ℃ with surrounding buildings and 23.82 ℃ near green spaces. The temperature with street trees was lower (24.45 ℃) than without (28.38 ℃) while it was 23.96 ℃ with vegetated median and 25.64 ℃ without. The temperatures were lower (24.70 ℃) on the permeable surface than on the impermeable surface (28.38 ℃). Model estimates show that the temperature decreases by 0.007 ℃ with an increase of 1 m² green (permeable space) space and the temperature with buildings tends to be 1.729 ℃ higher than that with green space. As green space increases by 1 m², the temperature tends to decrease by 0.017 ℃ on the roadway and by 0.012 ℃ on the sidewalk. Shade effect models show that street trees with shade affect temperature reduction by -3.884 ℃ on roadways and -3.314 ℃ on sidewalks. CONCLUSIONS : The results of this study demonstrate the differing effects of road characteristics on temperature. The roadway is more sensitive than the sidewalk to temperature changes and roadside vegetation, ambient green space, and pavement permeability contribute to temperature reduction.

여름철 도시 인근 산림에 의한 냉각효과의 정량화에 대한 연구

이호진,조성식,강민석,김준,이훈택,이민수,전지현,이채연,Britta Jänicke,조창범,김규랑,김백조,김현석 한국농림기상학회 2018 한국농림기상학회지 Vol.20 No.1

여름철 도시의 친환경적 기온 저감 방안으로 고려되는 산림에 의한 기온 저감 효과를 정량화 하기 위해 광릉 침⋅활엽수림과 인근 포천시의 도시 지역과의 기온차를 기온, 바람, 일사, 잠열 등의 미기상 인자를 이용하여 분석하였다. 2016년과 2017년의 6, 7, 8월 3개월 동안 산림 상⋅하부와 산림과 도심 지역의 평균 최대 기온차는 각각 -1.9℃, -3.4℃로 17시경에 나타났으며, 침⋅활엽수림 간의 차이는 없었다. 산림에 의한 기온 저감 효과는 14시부터 17시까지 누적된 증발산량, 일사량과 양의 상관관계를 나타냈으며, 풍속과는 음의 상관관계를 나타냈다. 이를 이용해 산림의 기온저감 효과를 정량화하는 모델을 개발하였다. 산림에 의한 야간 기온 저감 효과는 복사냉각으로 인한 찬공기의 생성과 생성된 찬공기가 산지의 하류로 이동하면서 발생하는 기온역전 현상에 의한 것으로 나타났다. 본 연구 결과를 서울시내 28개 AWS를 이용해 검증해 본 결과, 서울시 각 지역 주간의 기온은 식생의 증발산에 영향을 미치는 AWS 주변 식생 면적 및 규모와의 음의 상관관계를, 그리고 야간의 기온은 주변 식생 규모 및 인근 산림의 높이와 유의한 음의 상관관계를 재확인할 수 있었다. 따라서 도시림의 조성과 관리 및 산으로부터 바람길의 조성이 도시 온도 저감에 중요함을 알 수 있다. A variety of micro meteorological variables such as air temperature, wind, solar radiation and latent heat at Gwangneung forests (conifer and broadleaved forests) and AWS (Automated Weather Station) of Pocheon urban area were used to quantify the air temperature reduction effect of forests, which is considered to be an eco-friendly solution for reducing the urban heat island intensity during summer. In June, July and August of 2016 and 2017, the average maximum air temperature differences between above and below canopy of forests, and between the forests and urban areas were -1.9℃ and -3.4℃ respectively, and they occurred at 17:00. However, there was no difference between conifer and broadleaved forests. The effect of air temperature reduction by the forests was positively correlated with accumulated evapotranspiration and solar radiation from 14:00 to 17:00 and showed a negative correlation with wind speed. We have developed a model to quantify the effect of air temperature reduction by forests using these variables. The nighttime air temperature reduction effect by forests was due to the generation of cold air from radiative cooling and the air temperature inversion phenomenon that occurs when the generated cold air moves down the side of mountain. The model was evaluated in Seoul by using 28 AWSs. The evaluation shows that the air temperature of each district in Seoul was negatively correlated with the area and size of the surrounding tall vegetation that drives vegetation evapotranspiration during the day. During the night, however, the size of the surrounding tall vegetation and the elevations of nearby mountains were the main influencing factors on the air temperature. Our research emphasizes the importance of the establishment and management of urban forests and the composition of wind roads from mountains for urban air temperature reduction.

바나디움 산화물의 환원 및 질화반응으로부터 얻어진 바나디움 산화질화물의 제조, 특성분석 및 암모니아 분해반응에서의 촉매 활성

윤경희,신채호,Yun, Kyung Hee,Shin, Chae-Ho 한국화학공학회 2022 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.60 No.4

By varying various experimental conditions such as heating rate, molar hourly space velocity (MHSV), and nitridation reaction temperature, vanadium oxynitride was prepared through temperature programmed reduction/nitridation reaction (TPRN) of vanadium pentoxide and ammonia, and characterization were performed. In order to investigate the physico-chemical properties of the prepared catalyst, N₂ adsorption-desorption analysis, X-ray diffraction analysis (XRD), hydrogen temperature programmed reduction (H₂-TPR), temperature programmed oxidation (TPO), ammonia temperature programmed desorption (NH₃-TPD), transmission electron microscopy (TEM) was performed. Transformation of V₂O₅ with 5 m² g^-1 low specific surface area by reduction at 340 ℃ to V₂O₃ showed a high specific surface area value of 115 m² g^-1 by micropore formation. As the nitridation temperature increased beyond that, the specific surface area continued to decrease due to sintering. The nitridation reaction variable that had the greatest influence on the specific surface area was the reaction temperature, and the x + y value of VN_xO_y of a single phase approached from 1.5 to 1.0 as the nitridation reaction temperature increased. At a high reaction temperature of 680 ℃, the cubic lattice constant a was VN. close to the value. At 680 ℃, the highest nitridation temperature among the experimental conditions, the ammonia conversion rate was 93%, and no deactivation was observed.

거리협곡 벽면녹화 조성유형에 따른 미기상 변화 및 열환경 평가

김정호 ( Jeong Ho Kim ),최원준 ( Won Jun Choi ),윤용한 ( Yong Han Yoon ) 한국환경과학회 2016 한국환경과학회지 Vol.25 No.2

This study reduced and built Street Canyons created by skyscrapers in order to verify effect of Street Canyons by green wall within the city centre and analysed influence factors on temperature reduction according to applicative types of green wall in the lab. Applicative types were divided into three types such as non- greening type(Case A), one-side greening type(Case B), both side greening type(Case C). The result of analysis of each types showed that average temperature of Case B and Case C is respectively 1.0℃ and 1.7℃ lower than Case A. The result of analysis of WBGT was that the highest temperature was given by Case A(40.2℃) and second one was from Case B(39.8℃) and third one was from (39.1℃) and in UTCI Case A records the highest temperature of 34.7℃ and Case B provided the second highest temperature of 33.9℃ and Case B gave the lowest temperature of 32.7℃. In PMV the highest temperature of 2.65 was from Case B and second one of 2.61 was from Case A and third one of 2.54 was from Case C. Duncan analysis of each types based on solar radiation and thermal comfort generated that there was analytical significance between Case A and Case B and Case B in terms of each types of average temperature reduction. The significance of thermal comfort in WBGT, MRT, PMV showed non-significance but, In UTCI it was analysed that there was significance between Case C and Case A.

The effect of radiofrequency fat reduction system on porcine skin temperature and subcutaneous lipocytes

Yangwon Chae,Kwangsik Jang,Yesol Jo,Shamshik Shin,Sohi Kang,SeEun Kim,Kyung Mi Shim,Seong Soo Kang 한국실험동물학회 2021 한국실험동물학회 학술발표대회 논문집 Vol.2021 No.7

Introduction Radio frequency technology has been developed as a noninvasive method to reduce subcutaneous fat. This study aimed to measure the safety and effectiveness of the radiofrequency fat reduction system (RF system). We evaluated the efficiency of heat transfer to the subcutaneous layer by using ex vivo model. And then, we tried to verify the safety of the RF system by measuring skin surface temperature changes and the effectiveness by evaluating histological changes in subcutaneous lipocytes in pigs. Materials & Methods The RF system was developed and manufactured by PolyBioTech co., Ltd., Gwangju, Republic of Korea. In ex vivo model, fresh pork containing skin, subcutaneous, and muscle layer was treated with the RF system at 43℃ or 40℃ for 15 minutes. The temperature changes in the cut section of the pork were measured during treatment. In in vivo model, a dorsal skin of pig was also treated with the RF system at 45℃ for 30 minutes. The skin surface temperature of the pig was measured before and after treatment. Moreover, the treated sites were biopsied and evaluated histologically immediately, 1 day, and 7 days after treatment. Results In ex vivo model, the skin surface temperature of the pork did not exceed the set temperature value for most of the treatment time. And as the treatment time progressed, the heat gradually transferred to the deep layer. In in vivo model, the skin surface temperature of the pig remained below the set for the entire treatment time. In histological evaluation, no skin damage was observed and the sizes of subcutaneous lipocytes in pigs had shrunken by 27.87% immediately after, 30.83% 1 day after, and 34.81% 7 days after treatment. Conclusion The RF system used in this study effectively reduced subcutaneous fat without side effects such as skin damage. Based on this, it is expected that safe and effective use of this system will be possible for non-invasive fat reduction.

도시근린공원 미세먼지(PM)저감과 공간차폐율과의 관계 -대구광역시 수성구 근린공원을 중심으로-

구민아 한국조경학회 2019 韓國造景學會誌 Vol.47 No.6

The purpose of this study is to analyze how much particulate matter at the center of the urban park is reduced compared to the entrance of the park, where the particulate matter problem is serious. It also endeavored to analyze the relationship between the space closure rate and particulate matter reduction rate in the center of the park through the collection and analysis of experimental data. Seven flat land type urban neighborhood parks in Suseong-gu, Daegu were measured at the same place for three days. The research results are as follows. First, the center of the urban neighborhood park had an average temperature 1.05°C lower than at the entrance and an average humidity of 2.57% higher. Second, the rate of fine dust reduction was PM1- 17.09%, PM2.5- 17.65%, PM10- 14.99%. As for the reduction rate of particulate matter, the smaller the size of the park, the greater the reduction rate. In addition, the reduction rate at the center of the park was lower on days when particulate matter concentration based on the weather reports was low. The higher the concentration at the park entrance, the higher the reduction rate was. Third, a higher the rate of space closures at the center of the park resulted in a higher effect of particulate matter reduction. Noting this, the relationship between particulate matter reduction and the space closure rate in urban neighborhood parks was clearly shown. We hope to be the basis for more extensive experimental data collection. 본 연구는 미세먼지 문제가 심각한 도심에서 도시근린공원의 중심이 입구에 비해 어느 정도 저감된 공간인지 분석해 보는데 목적이 있다. 또한 공원중앙의 공간 차폐율과 미세먼지 저감율과의 상관관계를 실험을 통해 도출해 내고자 하였다. 대구시 수성구 평지형 도시근린공원 7개를 대상으로 3일동안 같은 장소에서 측정하였다. 연구결과, 첫째, 도시근린공원 중심은 입구보다 온도는 평균 1.05℃ 낮고, 습도는 평균 2.57% 높았다. 둘째, 미세먼지 감소율은 PM1 17.09%, PM2.5 17.65%, PM10 14.99%의 저감율로 초미세먼지가 더 높은 것으로 분석되었으며, 공원의 규모가 작을수록 저감효과가 더 높았다. 또한 기상청발표 미세먼지 농도가 높은날일수록 공원중앙에서의 저감율은 낮았으며, 공원입구의 농도가 높을수록 저감율은 높았다. 셋째, 공원중심에서 공간차폐율이 높을수록 미세먼지 저감효과가 높은 것으로 파악되었다. 도시근린공원의 미세먼지 저감정도와 공간 차폐율과의 상관관계를 파악할 수 있었으며, 더 확대된 실험데이터들의 기초가 되기를 기대한다.

온도에 따른 6가 크롬 함유 폐수의 환원-침전 처리 특성

유동주,한혜정,김동수 한국폐기물자원순환학회 2013 한국폐기물자원순환학회지 Vol.30 No.7

The effect of temperature on the removal process of Cr(VI) ion contained in wastewater by a precipitation method has been investigated for the improvement of its design and operation. The distribution diagram of chromium ion was constructed by employing the MINTEQ program and the quantitative feature of Cr(VI) depending on pH was investigated. As the temperature increases, the relative amount of H2CrO4 was examined to be raised and the pH range in which H2CrO4 exists as a stable form was also investigated to be extended according to the temperature. Cr(VI) ion was shown to be changed from HCrO4 - to Cr2O7 2- as the concentration of Cr(VI) ion is increased in the neutral pH condition and the concentration of Cr(VI) ion which is necessary for the ionic transformation was observed to rise in the acidic and alkaline conditions. The major reactant which involved in the reduction reaction for the removal of Cr(VI) ion was examined to be HCrO4 - and the reduction of Cr(VI) ion to Cr(III) ion was investigated to be influenced much by the temperature change at higher pH conditions. The reduction reaction of Cr(VI) ion for its removal as a precipitate was examined to be promoted as the temperature decreases and pH is lowered. In addition, the stable region of Cr(OH)3 was shown to be enlarged with temperature based on the thermodynamic estimation and it was thought to be necessary to design and control the precipitating process of Cr(VI) ion by considering the thermal characteristics of reduction and precipitation stage.

온도에 따른 탄탈 분말 제조와 특성

윤재식,박형호,배인성,이상백,김병일,Yun, Jae-Sik,Park, Hyeong-Ho,Bae, In-Seong,Lee, Sang-Baek,Kim, Byeong-Il 한국재료학회 2001 한국재료학회지 Vol.11 No.12

Pure tantalum powder has been produced by sodium as a reluctant, $K_2TaF_7$as a feed material and KCl/KF as a diluent in an inconel stainless steel bomb by the metallothermic reduction. The influence of experimental variable, such as temperature of reduction on the yield and characteristics of the Ta powder has been studied. As the temperature of the reduction was varied from$ 800{\circ}C~980{\circ}C$, the yield of tantalum powder increased from 41% to 56%. However no appreciable improvement was observed above$920{\circ}C$. The fraction of fine Ta Powder decreased appreciably with the increase of temperature, and particle size was$2~3{\mu}m$at reduction temperature of$920{\circ}C$.Therefore a reduction temperature of$920{\circ}C$was optimally fixed for subsequent runs.