• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.289-303
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• 2009

The chemical and meteorological effects on the concentration variations of ozone ($O_3$) were evaluated based on the intensive air quality measurement (5 pollutants and aromatic volatile organic compounds (AVOCs)) in and out-side an urban valley during spring and summer of 2006. The 5 pollutants measured in the study area include $O_3$, $NO_2$, NO, $PM_{10}$, and CO; the AVOCs include benzene (BEN), toluene (TOL), ethylbenzene (EB), m,p-xylene (MPX), and o-xylene (OX). For the purpose of this study, study areas were classified into two categories: valley area (VA) with a semi-closed topography covering a number of industrial complex, public building, and mountains and non-valley area (NVA) surrounding the suburban and residential areas. In general, the mean concentration levels of most pollutants (except for $PM_{10}$) in the VA were higher than those in the NVA. It was found that the average $O_3$ increase in the VA during spring might result from the combined effects such as the photochemical production from diverse anthropogenic sources and the $O_3$ accumulation due to geographical features (e.g., the semi-closed topography) and wind conditions (e.g., a low wind speed). In addition, the nocturnal $O_3$ increase in the VA during spring was primarily caused by local wind conditions (e.g., mountain and valley winds) with the low wind speed (approximately $1{\sim}2\;m\;s^{-1}$). On the other hand, the $O_3$ difference between the two areas during summer might be because of the photo-chemical production with the $O_3$ precursors (especially the AVOCs) rather than the contribution of wind conditions.

• Journal of Korean Society of Rural Planning
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• v.3 no.2
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• pp.71-80
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• 1997

The city's countryside is adjusting to change by urbanization. The recent changes in rural landuse and damages of local landscape characteristics are very serious. But, few studies address the relationship between land-use and quality of landscape for these area. The aim of this study is to clarify causes and problems of the change through investigating changes of landscape as a function of land-use. The results are as follows 1) The change of landscape can be seen as a functional of land-use. Landscapes are characterized by changes of regional environments. These are the urban-rural fringe area which need special consideration for urban development and also for rural landscape quality. 2) 11 types of landscape patterns are found for landscape management. these are Regional commercial area, Apartment development, Recreation & seisure, Golfs, Housing complex, Industrial complex, Vinyl house, Rural village, Evaded facilities, Rivers, Cultural heritages. These landscape types are explained as 'stimuli-responses model'in Bryant's Forces of urbanization. 3) The policy implications of these study are as follows : First is the necessity of landscape management in Grown Management Zone and Natural Reserved Zone in the Metropolitan level, Second is the necessity of development control in semi- agricultural area. The last is the necessary of long range management plan in the urban-rural fringe area.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.1048-1051
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• 2004

The environmental pollution by noise is recognized by the pollution source made it not only to carry out harm of the Quality of a life of people seriously in most countries, but was generated for most actual problems. The measure to such environmental noise must conduct first investigation which noise generating currently regarded as questionable says in what grade has resulted and the suitable measure by that is studied. The concern of the residents who demand such a comfortable living environment is increasing rapidly. Therefore, the three areas of Jeollabuk-Do judged that noise is comparatively severe was selected. It is going to grasp delicately the noise actual condition of a residential, semi-residential, commercial, industrial area.

• Journal of Marine Bioscience and Biotechnology
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• v.3 no.1
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• pp.42-47
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• 2008

Sudan is the largest country in Africa with an area of $2,505,810km^2$, of water constitutes $129,810km^2$, and cultivable land is 34%. Sudan has a total land boundary of 7,687 km with 9 border countries. This vast country embraces different vegetation patterns reflecting various climatic zones, grading from tropical rain forests in the south through semi-tropical savannah to arid zone in the extreme north, with annual rainfall ranging from 1,600 mm in the south to 25 mm in the north. The aquaculture industry is not developed as yet. Because of their basic characteristics, the Sudan inland and marine capture fisheries are of a small-scale and semi-industrial nature. The demand for fish and fish preparations is growing steadily. The animal resources sector (which includes fisheries) contributes 21% of Sudan GDP. The contribution of fisheries to Sudanese GDP is currently marginal. The per caput supply is only 1.6 kg/year, which is mostly obtained by capture fish landings. Despite the fact that fisheries GDP is extremely low, fish and fish preparations contribute to the food security of a wide sector of the rural and urban communities. Fisheries also provide work opportunities in the form of secondary employment as a source of income that indirectly contributes to household food security.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.422-426
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• 2009

Sweetpotato is one of the important starch crops, current more considered as an industrial crop rather than food because it has higher starch content (over 80% of biomass), it is used for bio resources for industrial area. In this study, we generated S598A (a mutant gene of oat phytochrome A) sweetpotato plant using Agrobacterium-transformation method. Morphological characteristics of S598A plant were compared with the wild type sweetpotato, S598A had darker green leaves, increased chlorophyll content higher than to two-fold, delayed leaf senescence, shorter plant height (60% shorter than that of the wild type), more number of leaves and petioles about 1.8-fold, shorter petiole length (30% shorter), 1.2-fold more branches and 1.6-fold thicker stem diameters. From this study, S598A plants with such phenotypic characteristics might be able to use the solar energy efficiently, to have increased tolerance to biotic and abiotic stresses and finally to increase productivity (not only starch yield but also root biomass yield). S598A sweetpotato lines are under field trials.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1D
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• pp.141-148
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• 2011

City of Incheon opened rapid transit(urban railroad line 1) in 1999 in order to relieve traffic congestion on major arterials. This research analyzed urban space changes of each station influenced area by examining the changes of residents, industrial employees, and floor area ratios before and after the open of Incheon urban railroad line 1. Analysis of variance was applied to change of station influence area. This research found out that the types of central business and agricultural station influence area had been changed significantly after the open of urban railroad. However, the residential, semi-residential, and suburban type of station influence area had not been changed after the open of urban railroad. Thus, it is necessary to provide diverse facilities for inducing residents and employees to the station influence area of residential and semi-residential. Furthermore, the suburban type of station influence area which is difficult to develop naturally by the law of Green Belt is needed to develop station influence area simultaneously with the construction of a station building.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.188-195
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• 2018

Time series analysis was conducted to identify the factors affecting short-term variation of water temperature in Wando. Spectrum analysis showed that air temperature peaks at diurnal period, while water temperature and tide level peak at both semi-diurnal and diurnal periods. Coherence between water temperature and the tide level presented 0.92 at semi-diurnal period. Numerical experiment were carried out to understand the spatio-temporal distribution of water temperature in the study area. Average water temperature difference between maximum ebb and flood was $0.3^{\circ}C$ in spring tide, but $0.13^{\circ}C$ in neap tide. The reason for the large difference in spring tide is that relatively cold water entered with strong tidal currents at flood tide and flowed out at ebb tide. Water temperature on coasts was higher than out at sea. This is because the depth in the coast is shallower than at sea, and water temperature increases rapidly due to solar radiation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.258-263
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• 2005

Because of its high performance and accuracy, electron beam welding has an important role in industrial applications such as semi-conductor and LCD manufactures. Since its operation has been done in a vacuum room, it is very difficult to check out their weldability as well as the correct welding area of the specimen. In this study, a measurement system of the electron beam welding has been developed based on the 3-axis LVDT controlled table. In addition, the algorithm to tracking the welding line has been developed. Welded regions were measured by using an A-scan ultrasonic sensor only. Weldability of the aluminum specimen has been tested by newly developed measuring system. The results are compared with those by using an C-scan ultrasonic sensor, which show good agreements with each other.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.155-161
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• 1999

The land reclamation area of Saemangeum(Kunsan) is located between 126$^{\circ}$10' E~126$^{\circ}$50' E and 35$^{\circ}$35' N~356$^{\circ}$05'N at the western coast of the Korean peninsula. The are many small islands including extensive areas of semi-diurnally flooded and dewatered tidal flats. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about 1.41m s-1 in ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Manjyung river and The Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m . The wind in winter is strong from the direction of northwest. In the past twenty years, land reclamation projects for agricutural purpose or industrial cocmplex have been mostly implemented along the western coast of Korea. Saemangeum coastal area is being constructed the33km sea dike and 40, 100ha reclamation area. The purpose of this study is to find the residual circulations in four seasons after the dike construction by a robust diagnostic and prognostic numerical model. Heat flux at the sea surface in January ,May , August , October was asopted on the basis on the daily inflow of solar radiation at the earth surface, assuming an average atomospheric transmission and no clouds , as a function of latitude and time of year(George L.P.J.E William, 1990). The discharge from the Geum , the Mankyung and the Dongjin rivers was adopted on the basis of experience formula of river flow in January , May ,August, October (The M. of C.Korea, 1993) . Water temperature and salinity along the open boundaries are obtained from the results of field observation s.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.92-106
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• 2004

Elemental dry deposition fluxes were measured using dry deposition plates from March to June 1998 in Seoul, Korea. During this spring sampling period several yellow sand events characterized by long-range transport from China and Mongolia impacted the area. Understanding the impact of yellow-sand events on atmospheric dry deposition is critical to managing the heavy metal levels in the environment in Korea. In this study, the measured flux of a primarily crustal metal, Al and an anthropogenic metal, Pb was used with two hybrid receptor models, potential source contribution function (PSCF) and residence time weighted concentration (RTWC) for locating sources of heavy metals associated with atmospheric dry deposition fluxes during the yellow-sand events in Seoul, Korea. The PSCF using a criterion value of the 75th percentile of the measured dry deposition fluxes and RTWC results using the measured elemental dry deposition fluxes agreed well and consistently showed that there were large potential source areas in the Gobi Desert in China and Mongolia and industrial areas near Tianjin, Tangshan, and Shenyang in China. Major industrial areas of Shenyang, Fushun, and Anshan, the Central China loess plateau, the Gobi Desert, and the Alaskan semi-desert in China were identified to be major source areas for the measured Pb flux in Seoul, Korea. For Al, the main industrial areas of Tangshan, Tianjin and Beijing, the Gobi Desert, the Alashan semi-desert, and the Central China loess plateau were found to be the major source areas. These results indicate that both anthropogenic sources such as industrial areas and natural sources such as deserts contribute to the high dry deposition fluxes of both Pb and Al in Seoul, Korea during yellow-sand events. RTWC resolved several high potential source areas. Modeling results indicated that the long-range transport of Al and Pb from China during yellow-sand events as well as non yellow-sand spring daytimes increased atmospheric dry deposition of heavy metals in Korea.