• Title/Summary/Keyword: Various Thermal Environment

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Assessment of Pollen Allergenicity Index Under Climate Change in the Seoul Children's Grand Park: Present, and Future (기후변화에 따른 도시 녹지 꽃가루 알레르기 지수 변화 분석 - 서울어린이대공원을 대상으로 -)

  • Yerin Hwang;Sukyoung Kim;Jaeyeon Choi;Chan Park
    • Journal of Environmental Impact Assessment
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    • v.33 no.3
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    • pp.99-115
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    • 2024
  • A worldwide effort is underway to utilize urban parks as a means ofresponding to climate change, providing various benefits to citizens. However, it also has several negative effects, such as an increase in pollen allergies. These negative impacts have been defined as ecosystem disservices and discussed globally, although the discussion remains insufficient domestically. In particular, pollen allergies have been discussed as a typical ecosystem disservice, with negative impacts such as an increase in symptoms attributed to higher pollen production or the growth of trees with higher antigenicity. The WHO reports that approximately 30% of the world's population suffers from pollen allergies. Many recent studies indicate that the harm induced by pollen allergies is expected to increase due to changes in the climate and thermal environment. In this context, we aim to diagnose the allergenicity of current urban parks and assess changes according to climate change scenarios. To achieve this goal, we assess pollen allergenicity in Seoul Children's Grand Park using the Urban Green Space Allergenicity Index (IUGZA) as the first step towards discussing ecosystem disservices. We found that the IUGZA value in the target area exceeds the threshold suggested in previous research, causing harm due to pollen allergies and is expected to increase according to climate change scenarios. We conclude that this result indicates that social harm from pollen allergies in urban parks may increase due to climate change. Therefore, we emphasize the necessity of discussing ecosystem disservices in the composition of urban parks.

Physiological Responses of Wearing Safety Helmet with Cooling Pack in Hot Environment (머리 냉각시의 인체생리반응 - 안전모 착용을 중심으로 -)

  • Choi, Jeong-Wha;Park, Joon-Hee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.6 s.165
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    • pp.955-965
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    • 2007
  • Safety helmets are used widely in various industries by workers since they are legally required to wear them. However, thermal discomfort is one of the major complaints from helmet users. To relieve this problem, frozen gelled packs can be considered for use inside the helmets. In this paper, tests were performed on humans to evaluate the physiological strains of wearing safety helmets and to investigate the effects of using frozen gelled packs inside the helmets. Experiments were conducted in a climatic chamber of WBGT $33{\pm}1^{\circ}C$ under four differed experimental conditions: 1) not wearing a safety helmet(NH); 2) wearing a safety helmet with frozen gelled pack A(HA); 3) wearing a safety helmet with frozen gelled pack B(HB); and 4) wearing only a safety helmet(OH). The results were as follows. First, when comparing NH with OH, physiological responses such as $\bar{T}_{sk},\;T_r$, HR and sweat rate were significantly higher in OH and subjective sensations were reported as less hot and more comfortable than NH(p<.05). Second, in regard to the frozen gelled packs inserted inside the safety helmets, some physiological responses in HA were different from those in HB, according to the two different types of packs. HA was hotter, more uncomfortable and less exhausted than HB. However, result from both HA and HB were lower than those from OH in terms of temperature and humidity inside safety helmet, sweat rate, $T_r$ increase, heat storage(p<.05). When wearing safety helmets with frozen gelled packs, it was shown that heat strain can be alleviated. These results are expected to help millions of workers who complain that wearing safety helmets is uncomfortable and messy.

A Characteristics and Improvement of Thermal Environment in Summer of Protected Horticulture Complex Using CFD Simulation (CFD 시뮬레이션을 이용한 시설원예단지 여름철 외부 열환경 특성 및 개선방안)

  • Son, Jin-Kwan;Kong, Min-Jae;Choi, Deuggyu;Kang, Dong-Hyeon;Park, Min-Jung;Yun, Sung-Wook;Lee, Seungchul;Lee, Si-Young
    • Journal of Korean Society of Rural Planning
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    • v.24 no.3
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    • pp.73-86
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    • 2018
  • Agricultural or rural landscape provides various ecosystem services. However, the ecosystem services function is declining due to various environmental problems such as climate change, land use change, stream intensification, non-point pollution and garbage. The A1B scenario predicts that the mean air temperature of South Korea will rise $3.8^{\circ}C$ degrees celsius in 2100. Agricultural sector is very vulnerable to climate change, so it must be thoroughly predicted and managed. In Korea, the facility horticulture complex is 54,051ha in 2016 and is the 3rd largest in the world(MAFRA, 2014). Facilities of horticultural complexes are reported to cause problems such as groundwater decrease, vegetation and insects diversity reduction, landscapes damage and garbage increase, compared with the existing land use paddy fields. Heat island phenomenon associated with climate change is also accelerated by the high heat absorption of horticultural sites. Therefore, we analyzed the heat island phenomenon occurring in the facility of horticultural complex in Korea. As an improvement measurement, I examined how much air temperature is reduced by putting the channel and the open space. In the case of the Buyeo area, the Computational Fluid Dynamics (CFD) simulation was analyzed for the average summer temperature distribution in the current land use mode at $38.9^{\circ}C$. As an improvement measurement, CFD simulation after 10% of 6m water channel was found to have an effect of lowering the summer temperature of about $2.7^{\circ}C$ compared with the present average of $36.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $34.7^{\circ}C$, which is $4.2^{\circ}C$ lower than the present. For the Jinju area, CFD simulations were analyzed for the average temperature of summer at $37.8^{\circ}C$ in the present land use pattern. As an improvement measure, CFD simulations after 10% of 6m water channel were found to have an effect of lowering the summer temperature of about $2.6^{\circ}C$ compared to the current average of $35.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $33.9^{\circ}C$, which is $3.9^{\circ}C$ lower than the present. It can be said that the effect of summer temperature drop in open space and waterway has been proven. The results of this study are expected to be reflected in sustainable agriculture land use and used as basic data for government - level policy in land use planning for climate change.

Effect of Cardanol Content on the Antibacterial Films Derived from Alginate-PVA Blended Matrix (알지네이트-폴리비닐알콜 블랜드 항균 필름 제조를 위한 카다놀 함량의 영향)

  • Ahn, Hee Ju;Kang, Kyung Soo;Song, Yun Ha;Lee, Da Hae;Kim, Mun Ho;Lee, Jae Kyoung;Woo, Hee Chul
    • Clean Technology
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    • v.28 no.1
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    • pp.24-31
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    • 2022
  • Petroleum-based plastics are used for various purposes and pose a significant threat to the earth's environment and ecosystem. Many efforts have been taken globally in different areas to find alternatives. As part of these efforts, this study manufactured alginate-based polyvinyl alcohol (PVA) blended films by casting from an aqueous solution prepared by mixing 10 wt% petroleum-based PVA with biodegradable, marine biomass-derived alginate. Glutaraldehyde was used as a cross-linking agent, and cardanol, an alkyl phenol-based bio-oil extracted from cashew nut shell, was added in the range of 0.1 to 2.0 wt% to grant antibacterial activity to the films. FTIR and TGA were performed to characterize the manufactured blended films, and the tensile strength, degree of swelling, and antibacterial activity were measured. Results obtained from the FTIR, TGA, and tensile strength test showed that alginate, the main component, was well distributed in the PVA by forming a matrix phase. The brittleness of alginate, a known weakness as a single component, and the low thermal durability of PVA were improved by cross-linking and hydrogen bonding of the functional groups between alginate and PVA. Addition of cardanol to the alginate-based PVA blend significantly improved the antibacterial activity against S. aureus and E. coli. The antibacterial performance was excellent with a death rate of 98% or higher for S. aureus and about 70% for E. coli at a contact time of 60 minutes. The optimal antibacterial activity of the alginate-PVA blended films was found with a cardanol content range between 0.1 to 0.5 wt%. These results show that cardanol-containing alginate-PVA blended films are suitable for use as various antibacterial materials, including as food packaging.

Hydrochemistry and Noble Gas Origin of Various Hot Spring Waters from the Eastern area in South Korea (동해안지역 온천유형별 수리화학적 특성 및 영족기체 기원)

  • Jeong, Chan-Ho;Nagao, Keisuke;Kim, Kyu-Han;Choi, Hun-Kong;Sumino, Hirochika;Park, Ji-Sun;Park, Chung-Hwa;Lee, Jong-Ig;Hur, Soon-Do
    • Journal of Soil and Groundwater Environment
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    • v.13 no.1
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    • pp.1-12
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    • 2008
  • The purpose of this study is to characterize the hydrogeochemical characteristics of hot spring waters and to interpret the source of noble gases and the geochemical environment of the hot spring waters distributed along the eastern area of the Korean peninsula. For this purpose, We carried out the chemical, stable isotopic and noble gas isotopic analyses for eleven hot spring water and fourteen hot spring gas samples collected from six hot spring sites. The hot spring waters except the Osaek hot spring water show the pH range of 7.0 to 9.1. However, the Osaek $CO_2$-rich hot spring water shows a weak acid of pH 5.7. The temperature of hot spring waters in the study area ranges from $25.7^{\circ}C$ to $68.3^{\circ}C$. Electrical conductivity of hot spring waters varies widely from 202 to $7,130{\mu}S/cm$. High electrical conductivity (av., $3,890{\mu}S/sm$) by high Na and Cl contents of the Haeundae and the Dongrae hot spring waters indicates that the hot spring waters were mixed with seawater in the subsurface thermal system. The type of hot springs in the viewpoint of dissolved components can be grouped into three types: (1) alkaline Na-$HCO_3$ type including sulfur gas of the Osaek, Baekam, Dukgu and Chuksan hot springs, and (2) saline Na-Cl type of the Haeundae and Dongrae hot springs, and (3) weak acid $CO_2$-rich Na-$HCO_3$ type of Osaek hot spring. Tritium ratios of the Haeundae and the Dongrae hot springs indicate different residence time in their aquifers of older water of $0.0{\sim}0.3$ TU and younger water of $5.9{\sim}8.8$ TU. The ${\delta}^{18}O$ and ${\delta}D$ values of hot spring waters indicate that they originate from the meteoric water, and that the values also reflect a latitude effect according to their locations. $^3He/^4He$ ratios of the hot spring waters except Osaek $CO_2$-rich hot spring water range from $0.1{\times}10^{-6}$ to $1.1{\times}10^{-6}$ which are plotted above the mixing line between air and crustal components. It means that the He gas in hot spring waters was originated mainly from atmosphere and crust sources, and partly from mantle sources. The Osaek $CO_2$-rich hot spring water shows $3.3{\times}10^{-6}$ in $^3He/^4He$ ratio that is 2.4 times higher than those of atmosphere. It provides clearly a helium source from the deep mantle. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

Estimation of Urban Heat Island Potential Based on Land Cover Type in Busan Using Landsat-7 ETM+ and AWS Data (Landsat-7 ETM+ 영상과 AWS 자료를 이용한 부산의 토지피복에 따른 여름철 도시열섬포텐셜 산출)

  • Ahn, Ji-Suk;Hwang, Jae-Dong;Park, Myung-Hee;Suh, Young-Sang
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.65-77
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    • 2012
  • This study examined changes in land cover for the past 25 years in Busan and subsequently evaluated heat island potential by using land surface temperature and observation temperature data. The results were as below. The urban area of Busan increased by more than 2.5 times for the past 25 years from 1975 to 2000. It was believed that an increase in the pavement area of city within such a short period of time was an unprecedented phenomenon unique to our country. It could be assumed that urban heat island would be worsened through this process. After analyzing the land temperature according to the land cover, it was shown that there were noticeable changes in the temperature of urban & built-up and mountain & forest areas. In particular, the temperature rose to $36{\sim}39^{\circ}C$ in industrial areas during the summer, whereas it went down to $22{\sim}24^{\circ}C$ in the urban areas at whose center there were mountains. It was found that heat island potential according to the level of land cover had various values depending on the conditions of land cover. Among the areas of urbanization, the industrial area's heat island potential is 6 to $8^{\circ}C$, and the residential and commercial area's is $0{\sim}5^{\circ}C$, so it has been found that there is high possibility to induce urban heat islands. Meanwhile, in the forest or agricultural area or the waterside, the heat island potential is $-6{\sim}-3^{\circ}C$. With this study result, it is possible to evaluate the effects of temperature increase according to the urban land use, and it can be used as foundational data to improve urban thermal environment and plan eco-friendly urban development.

Study on Basic Requirements of Geoscientific Area for the Deep Geological Repository of Spent Nuclear Fuel in Korea (사용후핵연료 심지층처분장부지 지질환경 기본요건 검토)

  • Bae, Dae-Seok;Koh, Yong-Kwon;Park, Ju-Wan;Park, Jin-Baek;Song, Jong-Soon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.10 no.1
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    • pp.63-75
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    • 2012
  • This paper gives some basic requirements and preferences of various geological environmental conditions for the final deep geological repository of spent nuclear fuel (SNF). This study also indicates how the requirements and preferences are to be considered prior to the selection of sites for a site investigation as well as the final disposal in Korea. The results of the study are based on the knowledge and experience from the IAEA and NEA/OECD as well as the advanced countries in SNF disposal project. This study discusses and suggests preliminary guideline of the disposal requirements including geological, mechanical, thermal, hydrogeological, chemical and transport properties of host rock with long term geological stabilities which influence the functions of a multi-barrier disposal system. To apply and determine whether requirements and preferences for a given parameter are satisfied at different stages during a site selection and suitability assessment of a final disposal site, the quantitative criteria in each area should be formulated with credibility through relevant research and development efforts for the deep geological environment during the site screening and selection processes as well as specific studies such as productions of safety cases and validation studies using a generic underground research laboratory (URL) in Korea.

DEVELOPMENT OF A LYMAN-α IMAGING SOLAR TELESCOPE FOR THE SATELLITE (인공위성 탑재용 자외선 태양카메라(LIST) 개발)

  • Jang, M.;Oh, H.S.;Rim, C.S.;Park, J.S.;Kim, J.S.;Son, D.;Lee, H.S.;Kim, S.J.;Lee, D.H.;Kim, S.S.;Kim, K.H.
    • Journal of Astronomy and Space Sciences
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    • v.22 no.3
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    • pp.329-352
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    • 2005
  • Long term observations of full-disk Lyman-o irradiance have been made by the instruments on various satellites. In addition, several sounding rockets dating back to the 1950s and up through the present have measured the $Lyman-{\alpha}$ irradiance. Previous full disk $Lyman-{\alpha}$ images of the sun have been very interesting and useful scientifically, but have been only five-minute 'snapshots' obtained on sounding rocket flights. All of these observations to date have been snapshots, with no time resolution to observe changes in the chromospheric structure as a result of the evolving magnetic field, and its effect on the Lyman-o intensity. The $Lyman-{\alpha}$ Imaging Solar Telescope(LIST) can provide a unique opportunity for the study of the sun in the $Lyman-{\alpha}$ region with the high time and spatial resolution for the first time. Up to the 2nd year development, the preliminary design of the optics, mechanical structure and electronics system has been completed. Also the mechanical structure analysis, thermal analysis were performed and the material for the structure was chosen as a result of these analyses. And the test plan and the verification matrix were decided. The operation systems, technical and scientific operation, were studied and finally decided. Those are the technical operation, mechanical working modes for the observation and safety, the scientific operation and the process of the acquired data. The basic techniques acquired through the development of satellite based solar telescope are essential for the construction of space environment forecast system in the future. The techniques which we developed through this study, like mechanical, optical and data processing techniques, could be applied extensively not only to the process of the future production of flight models of this kind, but also to the related industries. Also, we can utilize the scientific achievements which are obtained throughout the project And these can be utilized to build a high resolution photometric detectors for military and commercial purposes. It is also believed that we will be able to apply several acquired techniques for the development of the Korean satellite projects in the future.

Current Statues of Phenomics and its Application for Crop Improvement: Imaging Systems for High-throughput Screening (작물육종 효율 극대화를 위한 피노믹스(phenomics) 연구동향: 화상기술을 이용한 식물 표현형 분석을 중심으로)

  • Lee, Seong-Kon;Kwon, Tack-Ryoun;Suh, Eun-Jung;Bae, Shin-Chul
    • Korean Journal of Breeding Science
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    • v.43 no.4
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    • pp.233-240
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    • 2011
  • Food security has been a main global issue due to climate changes and growing world population expected to 9 billion by 2050. While biodiversity is becoming more highlight, breeders are confronting shortage of various genetic materials needed for new variety to tackle food shortage challenge. Though biotechnology is still under debate on potential risk to human and environment, it is considered as one of alternative tools to address food supply issue for its potential to create a number of variations in genetic resource. The new technology, phenomics, is developing to improve efficiency of crop improvement. Phenomics is concerned with the measurement of phenomes which are the physical, morphological, physiological and/or biochemical traits of organisms as they change in response to genetic mutation and environmental influences. It can be served to provide better understanding of phenotypes at whole plant. For last decades, high-throughput screening (HTS) systems have been developed to measure phenomes, rapidly and quantitatively. Imaging technology such as thermal and chlorophyll fluorescence imaging systems is an area of HTS which has been used in agriculture. In this article, we review the current statues of high-throughput screening system in phenomics and its application for crop improvement.