• Title/Summary/Keyword: Environmental Studies

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Physicochemical Characteristics of Particulate Matter Emissions of Different Vehicles' Fuel Types (자동차 연료유형에 따른 배출 입자상 물질의 화학적 특성)

  • Son, Jihwan;Kim, Jounghwa;Park, Gyutae;Kim, Sunmoon;Hong, Heekyoung;Moon, Sunhee;Park, Taehyun;Kang, Seokwon;Sung, Kijae;Chung, Taekho;Kim, Ingu;Kim, KyungHoon;Yu, Dong-Gil;Choi, Kwangho;Kim, Jeong Soo;Lee, Taehyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.6
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    • pp.593-602
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    • 2016
  • The physicochemical characteristics of particulate matter emissions from various vehicle's fuel types were studied at the facility of Transport Pollution Research Center(TPRC), National Institute of Environmental Research (NIER), Korea. Three different types of fuels such as gasoline, liquefied petroleum gas (LPG) and diesel were tested on the NIER driving mode and the constant speed modes(30, 70, and 110 km/h). Chemical composition of submicron particles from vehicle emissions was measured by the High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) during running cycles. Organics were dominant chemical species of particulate matter emissions for all three different vehicles' fuel types. Moreover, regardless of fuel types, emission rate of organics and inorganics decreased as the average speed of vehicle increased. The portion of fully oxidized fragment families of $C_xH_yO_z$ accounted for over 98% of organic aerosol(OA) in LPG and diesel vehicles, while the relatively high fraction of $C_xH_y$ in OA was observed in gasoline vehicle.

The Role of Gene-environment Interaction in Environmental Carcinogenesis (환경성 발암 기전에서 유전자-환경 상호작용의 역할)

  • Han, So-Hee;Lee, Kyoung-Mu
    • Journal of Environmental Health Sciences
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    • v.36 no.1
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    • pp.1-13
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    • 2010
  • Evidences supporting gene-environment interaction are accumulating in terms of environmental exposure including lifestyle factors and related genetic variants. One form of defense mechanism against cancer development involves a series of genes whose role is to metabolize (activation/detoxification) and excrete potentially toxic compounds and to repair subtle mistakes in DNA. The purpose of this article is to provide a brief review of the notion of gene-environment interaction, environmental/occupational carcinogens and related cancers, and previous studies of gene-environment interaction on cancers caused by exposure to carcinogenesis. With a number of studies on the interaction between lifestyle factors (e.g., smoking and diet) and genetic polymorphisms in genes involved in xenobiotic metabolism and DNA repair excluded, only several studies have been conducted on the interactive effects between polymorphisms of CYPs, GSTs, ERCCs, XRCCs and environmental/occupational carcinogens such as vinyl chloride, benzo[a]pyrene, and chloroform on carcinogenesis or genotoxicity. Future studies may need to be conducted with sufficient number of subjects and based on occupational cohorts to provide useful information in terms of advanced risk assessment and regulation of exposure level.

The physical geography in general:yesterday and tomorrow (자연지리학 일반: 회고와 전망)

  • Son, Ill
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.138-159
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    • 1996
  • There has been a tendency for Geomorphology and Climatology to be dominant in Physical Geography for 50 years in Korea. Physical Geography is concerned with the study of the totality of natural environment through the integrated approaches. But, an overall direction or a certain paradigm could not be found, because major sub-divisions of Physical Geography have been studied individually and the subjects and the approaches in studying Physical Geography are enormously diverse. A consensus of opinion could not also exist in deciding what kind of the sub-divisions should be included in the physical geography in general and how those should be summarized. Furthermore it would be considered imprudent to survey the studies of Physical Geography besides those of Geomorphology and Climatology due to the small number of researchers. Assuming that the rest of Physical Geographical studies with the exception of Geomorphological and Climatological studies are the Physical Geography in general, the studies of Physical Geogrpahy in general are summarized and several aspects are drown out as follows. First the descliption of all possible factors of natural environments was the pattern of early studies of Physical Geography and the tendency is maintained in the various kinds of research and project reports. Recently Physical Geographers have published several introductory textbooks or research monographs. In those books, however, the integrated approaches to Physical Geography were not suggested and the relationship between man and nature are dealt with in the elementary level. Second, the authentic soil studies of Physical Geographers are insignificant, because the studies of soil in Physical Geography have been mostly considered as the subsidiary means of Geomorphology Summarizing the studies of Soil Gegraphy by physical geographers and other Pedologists, the subjects are classified as soil-forming processes, soil erosions, soil in the tidal flat and reclaimed land, and soil pollution. Physical Geographers have focused upon the soil-forming processes in order to elucidate the geomorphic processes and the past climatic environment. The results of other subjects are trifling. Thirdy Byogeygrayhers and the results of studies are extremely of small number and the studies of Biogeography in Korea lines in the starting point. But, Biogeography could be a more unifying theme for the Physical-human Geography interface, and it would be expected to play an active part in the field of environmental conservation and resource management. Forth, the studies of Hydrogeography (Geographical Hydrology) in Korea have run through the studies of water balance and the morphometric studies such as the drainage network analysis and the relations of various kinds of morphometric elements in river. Recently, the hydrological model have introduced and developed to predict the flow of sediment, discharge, and ground water. The growth of groundwater studies is worthy of close attention. Finally, the studies on environmental problems was no mole than the general description about environmental destruction, resource development, environmental conservation, etc. until 1970s. The ecological perspectives on the relationship between man and nature were suggested in some studies of natural hazard. The new environmentalism having been introduced since 1980s. Human geographers have lead the studies of Environmental Perception. Environmental Ethics, Environmental Sociology, environmental policy. The Physical geographers have stay out of phase with the climate of the time and concentrate upon the publication of introductory textbooks. Recently, several studies on the human interference and modification of natural environments have been made an attempt in the fields of Geomorphology and climatology. Summarizing the studies of Physical Geography for 50 years in Korea, the integrated approaches inherent in Physical Geography disappeared little by little and the majol sub-divisions of Physical Ceography have develop in connection with the nearby earth sciences such as Geology, Meteorology, Pedology, Biology, Hydrology, etc been rediscovered by non-geographers under the guise of environmental science. It is expected that Physical Geography would revive as the dominant subject to cope with environmental problems, rearming with the innate integrated approaches.

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A Review of the Survey Method of the Korean National Household Travel Survey: Focusing on the Comparison of International Cases

  • Gim, Tae-Hyoung Tommy;Cho, Hyung-Wook;Kim, Moon-Hyun;Park, Jae-Hee;Bayarsaikhan, Tsolmon;Joo, Hee-Soo
    • Land and Housing Review
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    • v.13 no.1
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    • pp.85-98
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    • 2022
  • The increasing use of various types of data to capture travel behavior relatively discredits the utility of traditional national-scale household travel surveys. However, the surveys are still arguably meaningful in their clarification of purposes and means of travel. Accordingly, this study reviews travel survey cases and related literature, to identify the status of the Korean National Household Travel Survey (KNHTS). It discusses improving the KNHTS's survey method, focusing on its long investigation cycle, short survey period, reduction in sample size, and questionnaire format biased toward mandatory travel. To address these issues, this study suggests reducing the survey cycle, conducting a year-round survey, combining weekday and weekend surveys, and specifying items on nonmandatory travel. These practical suggestions duly consider the validity and reliability of the KNHTS within budget constraints and its applicability to related fields, such as tourism, public health, and sociology.

Research on Influence Factors on Pulmonary Functions in Korean-Chinese Children

  • Kim, Dae-Seon;Yu, Seung-Do;Cha, Jung-Hoon;Na, Jin-Gyun
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2003.06a
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    • pp.192-195
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    • 2003
  • To identify the difference between Korean-Chinese and Korean children's variation of pulmonary function with personal factors (suck as age, height, and weight), we performed pulmonary function test (PFT) and measured personal factors of 200 Korean-Chinese children participants from two elementary schools of Beijing and Melons city in China. Regression analysis was utilized to determine which personal factors were significantly correlated with PFT measure (FVC and FEV$_1$). We compared the regression model from this study with those of other studies of Korean children. Similar to other studies, we found that the most important variable, influencing PFT measure, was height, whereas addition of either age or weight in the regression virtually did not increase the accuracy. As the result of comparison of the regression model from this study with those of other studies of Korean children, variation in FVC or FEV$_1$ with height were similar.

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Ion Concentrations of Particulate Matter in Yongin in Spring and Fall (봄철과 가을철 용인지역 입자상 물질의 이온 농도)

  • Won, Soo-Ran;Choi, Yong-Joo;Kim, A-Rong;Choi, Soon-Ho;Ghim, Young-Sung
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.3
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    • pp.265-275
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    • 2010
  • Mass and ion concentrations of $PM_{10}$ and $PM_{2.5}$ were measured in Yongin, downwind of the Seoul metropolitan area. Twenty-four hour average samples were collected daily for a month or so in spring and fall of both 2007 and 2008. Asian dust occurred twice in each period except in the fall of 2007. During the Asian dust period, nitrate in fine particles decreased since large amount of cations in coarse particles of Asian dust absorbed it. In spring 2008, sulfate as well as ammonium also increased in coarse particles. In spite of occasional Asian dust events, the influence of secondary formation was dominant over the period. Excessive ammonium over sulfate was enough to neutralize nitrate as well. High correlation coefficients between $K^+$ and sulfate, nitrate, and ammonium indicate a close relationship between secondary formation and biomass burning. Biomass burning and open burning are considered to be important sources of chloride.

Current Trend of Studies on 'Culture' in the field of Environmental Design (국제학술논문에 나타난 '문화' 에 관한 연구의 최근 경향 분석 - 환경디자인 분야를 중심으로 -)

  • 박지연;이연숙
    • Korean Institute of Interior Design Journal
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    • no.38
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    • pp.21-29
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    • 2003
  • This study began to classify the studies on 'culture' in the field of environmental design overall. The classifying process adopted not the approach to preselect the criteria but the phenomenological inductive approach and content analysis method focusing on environmental design in order to understand which place the environmental design had taken. As a result, following aspects were reviewed: what is the area in which the studies on culture is made under the environmental design; what is the trend of using the word 'culture' in terms of logical connection; what is the level of approach to culture from the viewpoint of search, correspondence or application stage. On the whole, followings were drawn as conclusions. First, the interest of the studies on culture has been increased with time especially in the field of interior design. Second, the word 'culture' has become to be used a lot as 'cultural', and was used together with traditional, enterprise and material. Lastly, culture was studied at a starting point by and large. Although the papers, the objects of this study, are confined to five kinds of journals, the analysis of them is helpful to preestimate the trend of studies on culture because they have propensity to lead the international professional academic world.

Population Dynamics of Phage-Host System of Microlunatus phosphovorus Indigenous in Activated Sludge

  • Lee, Sang-Hyon;Otawa, Kenichi;Onuki, Motoharu;Satoh, Hiroyasu;Mino, Takashi
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1704-1707
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    • 2007
  • Monitoring of the phage-host system of Microlunatus phosphovorus indigenous in activated sludge was attempted. A laboratory-scale activated sludge process was operated for 5 weeks with synthetic wastewater. The phage-host system population in the process was monitored by plaque assay and FISH methods at every 3 days. During the process operation, the phage-host system populations were more or less steady, except for 1 week in the middle of the operation. In that period, initially M. phosphovorus decreased significantly and its lytic bacteriophages increased, and then M. phosphovorus increased back to its original level while its lytic bacteriophages decreased. This observation suggests that lytic bacteriophages should be considered as one of the biological factors affecting the bacterial population dynamics in activated sludge processes.