• Korean Journal of Human Ecology
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• v.9 no.3
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• pp.37-45
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• 2006

The purpose of this study was university student's preference for own house in future according to gender. This was the investigation of which 512 university students in Jeollabukdo province. In this statistical analysis, SPSS 11.5 program was utilized to calculate percentage, mean and standard deviation. Also, these materials were verified by factor analysis, t-test and $x^2$-test. The results of this study were as follows: The university students' future housing environment preferences has been appeared to be higher in the environmental equipment and the natural scenery. In the case of the gender variables was appeared to be higher for female than male students. The future housing area most of the university students wanted the medium city or over, $25{\sim}33\;p'y{\breve{o}}ng$ apartment, 3 bed rooms, 2 bathroom. In case most students have a yard in their future house, they'd like to grow lawn and trees. Also, they wanted to live in a short distance with their future parents-in-law. Therefore, It was desirable that make a plan based on the results of this study future-residing for the new generation.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1137-1143
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• 2006

In this study we investigated the removal characteristics of NOM and bromate formation characteristics in SOMT reactor. The system was recently developed as a novel ozone reactor and installed in SJ pilot plant. DOC values were decreased within 3% after treatment of 0.5~2.0 mg/L ozone dosage in SOMT reactor while the $UV_{254}$ value was 69% decreased at 2.0 mg/L ozone dosage. The composition of NOM was analysed by LC-OCD (Organic Cabon Detector) after ozone treatment in SOMT reactor to elucidate the variation of NOM character. Polysaccharide (more than 20,000 g/mol) fraction of NOM was decomposed while building blocks (350~500 g/mol) and neutral (less than 350 g/mol) fraction increased. Spiked bromide reacted with 0.5~2.0 mg/L ozone dosage in the SOMT reactor. The bromate formation was proportional to the ozone dosage ($R^2=0.978$) but not proportional to reaction time. The maximum concentration of formated bromate was not exceeded to 10% of spiked bromide concentration.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.63-66
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• 2003

This study applied a hydrogeological field survey and isotope investigation to identify source locations and delineate pathways of groundwater contamination by nitrogen compounds. The infiltration and recharge processes were analyzed with groundwater-level fluctuation data and oxygen-hydrogen stable isotope data. The groundwater flow pattern was investigated through groundwater flow modeling and spatial and temporal variation of oxygen isotope data. Based on the flow analysis and nitrogen isotope data, source types of nitrate contamination in groundwater are identified. Groundwater recharge largely occurs in spring and summer due to precipitation or irrigation water in rice fields. Based on oxygen isotope data and cross-correlation between precipitation and groundwater level changes, groundwater recharge was found to be mainly caused by irrigation in spring and by precipitation at other times. The groundwater flow velocity calculated by a time series of spatial correlations, 231 m/yr, is in good accordance with the linear velocity estimated from hydrogeologic data. Nitrate contamination sources are natural and fertilized soils as non-point sources, and septic and animal wastes as point sources. Seasonal loading and spatial distribution of nitrate sources are estimated by using oxygen and nitrogen isotopic data.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.73-76
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• 2003

SF$_{6}$ (Sulfur Hexafluoride) is a gaseous compound whose use is being greatly increased recently. The compound has a negligible background concentration from natural sources and is stable in most of groundwater environments. Therefore, SF$_{6}$ has potential for a dating tool for young groundwater. It has many advantages over chlorofluorocarbons (CFCs) for groundwater investigation that sampling procedure is much simpler than CFCs and its growth is continued up to at least near future in the atmosphere. However, solubility of SF$^{6}$ is so low that excess air causes large uncertainties in recharge date of groundwater. To compensate the limitation, $N_2$/Ar method can be employed to estimate excess air content. A groundwater study is currently carrying out in Jeju Island using SF$_{6}$ as an environmental tracer, Well waters and spring waters were sampled for SF$_{6}$ and $N_2$/Ar. To establish SF$_{6}$ input history in the study area, air sampling is being conducted in the area near the center of the island on a monthly and weekly basis. Based on the present data, the level of SF$_{6}$ concentration in the atmosphere of the Island is corresponding to the trend of the Northern Hemisphere.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.28-35
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• 1997

Biosystematic study on Euphorbia ebracteolata Hayata was carried out by comparing ecology and morphology between wild and cultivated ones. As the result of this study, cultivation method about this medicinal plant was established, and ecologically, the shape of leaf or root of this plant appeared to be dependent on ecological environment while the hair of ovary and the involucel were considered to be fixed characters. From the investigation of natural conditions of habitats, this plant was considered to be a facultive sciofytes and a day neutral plant.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.65-73
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• 2015

The hydrofluoric acid (HF) leakage accident occurred on September 2012 in Gumi, Korea affected the surrounding soils and plants. In this study, we investigated fluoride migration in Gumi area through geochemical properties of soil-liquid phase (pore water F and water-soluble F). The concentrations of porewater F and water-soluble F were obtained from N.D (Not detected) to 9.79 mg/L and from 0.001 to 21.4 mg/L, respectively. F in pore water seemed to be affected by artificial and natural origin, and PHREEQC results implied that fluorite is F control factor. F concentrations of soil and soil-liquid phase did not exceed concern level of regulatory criteria and showed similar trends compared by previous studies. Therefore, F contents remained in the soil and soil-liquid phase were considered to be not affected by HF leakage accident.

• Advances in environmental research
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• v.3 no.3
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• pp.253-281
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• 2014

The quest for enhanced thermal comfort for dwellings encompasses the holistic utilization of improved building fabric, impact of weather variation and amongst passive cooling design consideration the provision of appropriate ventilation and shading strategy. Whilst thermal comfort is prime to dwellings considerations, limited research has been done in this area with the attention focused mostly on non-dwellings. This paper examines the current and future thermal comfort implications of four different standard construction specifications which show a progressive increase in thermal mass and airtightness and is underpinned by the newly developed CIBSE adaptive thermal comfort method for assessing the risk of overheating in naturally ventilated dwellings. Interactive investigation on the impact of building fabric variation, natural ventilation scenarios, external shading and varying occupants' characteristics to analyse dwellings thermal comfort based on non-heating season of current and future weather patterns of London and Birmingham is conducted. The overheating analysis focus on the whole building and individual zones. The findings from the thermal analysis simulation are illustrated graphically coupled with statistical analysis of data collected from the simulation. The results indicate that, judicious integrated approach of improved design options could substantially reduce the operating temperatures in dwellings and enhance thermal comfort.

• Mycobiology
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• v.49 no.6
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• pp.551-558
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• 2021

The Federated States of Micronesia (FSM) is an island country in the western Pacific and is a known biodiversity hotspot. However, a relatively small number of fungi (236 species) have been reported till July 2021. Since fungi play major ecological roles in ecosystems, we investigated the fungal diversity of FSM from various sources over 2016 and 2017 and constructed a local fungal inventory, which also included the previously reported species. Fruiting bodies were collected from various host trees and fungal strains were isolated from marine and terrestrial environments. A total of 99 species, of which 78 were newly reported in the FSM, were identified at the species level using a combination of molecular and morphological approaches. Many fungal species were specific to the environment, host, or source. Upon construction of the fungal inventory, 314 species were confirmed to reside in the FSM. This inventory will serve as an important basis for monitoring fungal diversity and identifying novel biological resources in FSM.

• Environmental Engineering Research
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• v.22 no.4
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• pp.407-416
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• 2017

$CO_2$ emission is increasingly focused by public. Beijing and Tianjin are conceived to be a new economic point of growth in China. However, both of them are suffering serious environmental stress. In order to seek for the effect of socioeconomic factors on the $CO_2$ emission of this region, a novel methodology -symbolic regression- is adopted to investigate the relationship between $CO_2$ emission and influential factors of Beijing and Tianjin. Based on this method, $CO_2$ emission models of Beijing and Tianjin are built respectively. The models results manifested that Beijing and Tianjin own different $CO_2$ emission indicators. The RMSE of models in Beijing and Tianjin are 255.39 and 603.99, respectively. Further analysis on indicators and forecast trend shows that $CO_2$ emission of Beijing expresses an inverted-U shaped curve, whilst Tianjin owns a monotonically increasing trend. From analytical results, it could be argued that the diversity rooted in different development orientation and the mixture of different natural and industrial environment. This research further expands the investigation on $CO_2$ emission of Beijing and Tianjin region, and can be used for reference in the study of carbon emissions in similar regions. Based on the investigation, several policy suggestions are presented.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.431-440
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• 2008

Turbid water or suspended sediment is associated with negative effects on aquatic organisms; fish, aquatic invertebrate, and periphyton. Effects of turbid water on fish differ depending on their developmental stage and a level of turbidity. Low turbid water may cause feeding and predation rates, reaction distance, and avoidance in fish, and it could make fish to die under high turbidity and long period. Therefore, it is very important to find out how turbid water or suspended sediment can affect fish in domestic watersheds. The objectives of this study were 1) to introduce international case studies and their standards to deal with suspended sediment, 2) to determine acute toxicity in 4 major freshwater fishes, and 3) to determine in relation to adverse effect of macroinvertebrates and fish. Impacts of turbid water on fish can be categorized into direct and indirect effects, and some factors such as duration and frequency of exposure, toxicity, temperature, life stage of fish, size of particle, time of occurrence, availability of and access to refugia, etc, play important role to decide magnitude of effect. A review of turbidity standard in USA, Canada, and Europe indicated that each standard varied with natural condition, and Alaska allowed liberal increase of turbidity over natural conditions in streams. Even though acute toxicity with four different species did not show any fatal effect, it should be considered to conduct a chronic test (long-term) for more detailed assessment. Compared to the control, dominance index of macroinvertebrates was greater in the turbid site, whereas biotic index, species diversity index, species richness index, and ecological score were smaller in the turbid site. According to histopathological analysis with gills of macroinvertebrate and fishes, morphological and physiological modification of gills due to suspended sediments can cause disturbance of respiration, excretion and secretion. In conclusion, in order to maintain good and healthy aquatic ecosystem, it is the best to minimize or prevent impact by occurrence of turbid water in stream and reservoir. We must make every effort to maintain and manage healthy aquatic ecosystem with additional investigation using various assessment tools and periodic biomonitoring of fish.