• Journal of Environmental Science International
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• v.27 no.7
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• pp.489-497
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• 2018

In this study, the ion index characteristics of small and medium urban land use types were investigated in the city of Chungju. The average temperature for each land use type was in the order: general commercial district ($29.59^{\circ}C$) > general residential district ($28.34^{\circ}C$) > productive green district ($28.31^{\circ}C$). The average relative humidity was in the order: productive green district (70.12%) > general residential district (69.93%) > general commercial district (66.48%). The average wind speed was in the order: productive green district (0.95 m/s) > general commercial district (0.87 m/s) > general residential district (0.54 m/s). Positive and negative ions were investigated to determine the ion index by land use type. The average amount of positive ion generated was in the order: general commercial district ($737ea/cm^3$) > general residential district ($492ea/cm^3$) > productive green district ($445ea/cm^3$). The average negative ion production decreased in the order: productive green district ($930ea/cm^3$) > general residential district ($754ea/cm^3$) > general commercial district ($744ea/cm^3$). The ion index calculated from measured data can be arranged in the order: productive green district (2.09) > general residential district (1.53) > general commercial district (1.01). These results confirm the state of positive and negative ion generation in each land use type. Further, the differences in the ion index by land use type were confirmed. However, a limitation of this study is that simple summer measurements were conducted, and seasonal characteristics were not considered. Therefore, any future investigation and research should consider seasonal variation characteristics.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.879-891
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• 2012

The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.337-341
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• 2005

It is difficult to use average sewage water quality as a design parameter for the individual sewage wastewater treatment plant(ISWTP), because sewage water quality is very various according to the building use type. So, in this study, we estimated daily, seasonal and weekly trend of sewage water quality and flow rate in various kind of building to comprehend operating state of ISWTP. The sewage water quality and flow rate were higher in the business building than household building. The seasonal difference of the water quality was not detected but that of flow rate was high. The flow rate of the sewage in the business building was higher in summer than in other seasons and in weekend than in weekday. The treatment efficiency of IWSTP was about $70{\sim}80%$ with BOD, $40{\sim}50%$ with TN and TP, which was very low. The unit loads of the individual house were 36.05 gpcd with BOD, 37.91 gpcd with SS, 23.91 gpcd with T-N, and 7.90 gpcd with T-P respectively, and those values were higher than other studies. It is because, as distinct from other studies, sewage water quality was monitored at the inlet point of the IWSTP in this study. We can use this results as an one of basic parameters for the design of IWSTP.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.150-158
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• 2001

Maintenance open spaces and community development in large scale housing development is one of the most important issues. We(UDC) established a resident participation activity for maintenance and use open space with community development in Hachioji New Town from 1997. The purpose of this study is to establish resident participation activities for maintenance and use open space with community development in Hajichioji New Town, and to clarify the characteristics and to on sider about efficiency of the activity. We established Minamino Shizen-Juku as a methodology for maintenance and use open spaces at the same time Hachioji New Town was opened in 1997. The activity has continued by now in 2001. We conducted questionnaire survey to make sure efficiency and characteristics of the activity past three years. Minamino Shizen-Juku (nature friendly lessons) is a resident participation activity in Hachioji New Town. It was established in 1997 as soon as the new town was opened, this year is fifth since it was started. It has three objects. 1)Maintenance and use woody environment, 2) Community development, 3) Continuation and renewal native culture. And it has general course, three special courses and one extra course were established in the activity. 1) General course is an activity participated all of member. It's included farming experience in the native field and seasonal events. 2) Rice growing and woods maintenance course is rice growing and wild wood maintenance in the park as a series of annual farming activities. 3) Benefaction from farm course is started from planting spring vegetable at Mizukoshi(Leader of Minamino Shezen-Juku)'s field. There is the number of participant limit because of the area of the field. 4) Watching nature course is watching seasonal wild flowers, trees, animals and plants to know about native nature. 5) Extra program is programmed to know about native history and tradition. It's planned including participant's ideas. Not member can participate in this course too.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.210-215
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• 2004

The Purpose of this study are to develop the simulation(Tank model, Rainfall-runoff model) for the estimation of wily river discharge and for evaluation of wily pollutant loads from the watersheds of the objected basin area. As apply this constructed Tank model to Nakdong river region, we evaluated the wily river discharge of Nakdong river from use-land conditions, precipitation and evaporation data of 3 years(from 1998 to 2000) and investigate the seasonal fluctuation of SS, COD, TN, TP inflowing into Nakdong river. The result shows that summer has high pollutant level than winter in seasonal characteristic and the down stream has high pollutant level than the upper stream. The annual average of SS, COD, TN, TP flawing in Nakdong river(Samranjin) was estimated each 691ton-COD/year, 1854.2ton-SS/year, 382.8ton-TN/year and 13.0ton- TP/year.

• Proceedings of the KSRS Conference
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• v.1
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• pp.352-355
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• 2006

In this study, the seasonal and inter-annual variation of sea surface current in the Gulf of Thailand were revealed through the use of WOD temperature and salinity data and monthly sea surface dynamic heights (SSDH) from TOPEX/Poseidon and ERS-2 altimetry data during 1995-2001. The mean dynamic height and mean geostrohic current were derived from the climatological data while SSDH data gave monthly dynamic heights and their geopstrophic currents. The mean geostrophic current showed strong southward and westward flow of South China Sea water along the gulf entrance. Counterclockwise eddy in the inner gulf and the western side of the gulf entrance associated with upwelling in the area. Seasonal geostrophic currents show basin-wide counterclockwise circulation during the southwest monsoon season and clockwise circulation during the northeast monsoon season. Upwelling was enhanced during the southwest monsoon season. The circulation patterns varied seasonally and inter-annually probably due to the variation in wind regime. And finally we found that congregation, spawning, and migration routes of short-bodied mackerel conform well with coastal upwelling and surface circulation in the gulf.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.41-50
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• 2009

Chain-linking is a method for aggregating volume measures which would improve the quality of estimates of economic growth over the present fixed base in Korea. There is a risk that choice of chain-linking techniques such annual overlap, one-quarter overlap or over-the-year overlap may create an artificial seasonality to the volume series. The empirical results on Korean GDP suggest that the use of the annual overlap is recommended. And conducting seasonal adjustment after chain-linking to produce the chain-linked seasonally adjusted GDP is more appropriated in Korea.

• Journal of Environmental Science International
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• v.14 no.8
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• pp.739-748
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• 2005

The purpose of this study is to analyze seasonal changes in structure and landscape of Gongji stream corridor in Chuncheon, and to suggest some guidelines to contribute to creating a desirable close-to- nature stream. The study seasonally surveyed floodplain and revetment conditions, channel micro-topography, streamflow level and velocity, and vegetational cover. Flooding, water level, and vegetation were major factors of affecting seasonal changes in streambed structure and stream landscape. Small sand bars and islands were considerably disturbed by flooding and water level change. However, large islands and sand bars in the upper and middle section of the study stream remained or reappeared even after flooding. Flooding also tended to repeat channel sedimentation at the same spot. Controlling water volume of the Euiam Lake, which is adjacent to the study stream, caused higher water level downstream in the dry seasons. The majority of vegetation in sand bars and islands was washed away by the floods. Vehicle passing, crop cultivation, and ball game were other elements which disturbed vegetation in the floodplain. Creating a close-to-nature stream should reflect micro-topographical changes of channel by flooding, prevent improper vehicle entry and human use, and remove concrete material in the revetment and floodplain.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2008.04a
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• pp.52-54
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• 2008

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.68-70
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• 2003

This paper proposes the demand-side management(DSM) monitoring system of high efficient end-use appliances considering demand-side bidding (DSB). The effect on the market propagation of high efficient appliances by demand side bidding is analysed. Seasonal Peak demand forecasting and propagation capacity of these appliances are analysed.