• The Korean Journal of Ecology
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• v.20 no.6
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• pp.451-459
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• 1997

Seasonal and spatial distribution of vascular plants were examined and related to soil texture, pH, moisture and nutrient contents in the riparian zone of the Balan Stream. In spring the area was dominated by Alopecurus aequalis var. amurensis, was displaced by Persicaria thunbergii and Humulus japonicus in summer. From the stream channel to bank, soil texture and pH were not significantly differentiated, moisture decreased, organic matter and K increased, and TKN and available P increased in June and decreased in August. DCA ordination analysis by species distribution showed spatially and seasonally distinct patterns seasonal difference was evident on axis 1, and spatial difference according to the distance from stream channel was clear, too. Both axis 1 and axis 2 scores were significantly correlated with biomass, pH, and phosphate. Species richness increased were significantly correlated with biomass, pH, and phosphate. Species richness increaed with increasing organic matter and phosphate, and decreased with increasing soil moisture and K. Biomass increased with increasing organic matter, but was negatively related to pH, moisture, TKN, available P and K. Available P was significantly correlated with biomass, pH, and total soil nitrogen. In conclusion, the distribution of riparian vegetation was governed by soil physico-chemical properties, which are primarily determined by how far it is from the stream channel.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.6
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• pp.133-144
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• 2010

The objective of this planning proposal is to rehabilitate the urban stream which has been ecologically disturbed in the urban process. The experimental stream, Su-am stream located in Anyang City is typical urban stream in adjacent land use and the spatial condition. The stream in the watershed context, is the second tributary of Han River, in the Anyangcheon watershed. The Characteristics of the stream reach were analyzed by the river corridor survey. In the conceptual phase, Rehabilitation Programs were established based on the hydrological, ecological and spatial characteristics of the stream. Spatial zoning concept according to the characteristics of the stream and adjacent land use, was suggested 4 types of zoning; ecological preservation zone, natural landscape zone, neighborhood water-friendly zone and CBD water-friendly zone. Implementation Practices can be summarized as follow: For The longitudinal river continuum, some In-stream practices were suggested and implemented; such as channel alignment, step & pool, pool & riffle and low-flow channel bank. For latitudinal continuum and intimate spatial relationship between Sam-duk Park & Su-am stream, gentle sloped bank was planned and implemented. After stream improvement & ecological Implementation, follow-up monitoring and adaptive management programs will be a meaningful process for ecological rehabilitation.

• Journal of Environmental Impact Assessment
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• v.19 no.2
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• pp.127-140
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• 2010

This study investigates the relation between the location of a habitat and the ecological connections according to the habitat type in the riparian zone at the Nonsan Stream and Yanghwa Stream. Stream habitat is classified into nine types for the aquatic insects and fish. For vegetation and birds, habitat is classified into two types of medium-scale streams, including both physical and chemical streams are analyzed accordingly. Nowadays, The fundamental goal of the river environment restoration enterprise is the rehabilitation or the restoration of the characteristic the river scenic or environment. For instance, The Channel habitats which has physical nature environment such as flat, speedy rapids, or closed-channel wetland, pool are constructed by artificial, Consequently, make them autogenesis smoothy eco-environment. However, the river environment are controlled not only physical environment, but it also need reasonable the quality of the water to compose smoothly. Finally, understanding what influence are effecting on physical habitat environment which are made by natural factors to water quality are very important factor for the river environment restoration enterprise Therefore, In this research, we are targeting to a basin to investigate the environment of the physical channel habitat and evaluate the changing of the water quality. This results will be a important characteristic that can judge the physical habitat and reciprocality connected to the water quality or adequacy of restoration technology. Therefore in this study, as a step to quantify functions and values of habitats and definite factors to perform habitat, we selected a representative stream of sand-stream, gravel-stream to classify habitat characteristics and quantified the physical, chemical, biological characteristics.

• Ecology and Resilient Infrastructure
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• v.5 no.4
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• pp.229-245
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• 2018

This study aims to investigate the changes in the riparian vegetated area in the Naeseong stream, an unregulated river, in order to analyze the main factors leading to these changes. For this purpose, the land surface cover in the channel area of the Naeseong stream was classified into 9 categories using past aerial photographs collected between 1970 and 2016, which recorded the long-term changes of the Naeseong stream. The increase or decrease in the vegetated area was calculated for each category using a pair of before and after images. The changes in the vegetated area were divided into 6 periods: the unvegetated channel period (1970 - 1980), the first rapid increase (1980 - 1986), the period of decrease due to flood (1986 - 1988), the period of repetitive man-induced disturbance and vegetation increase (1988 - 2008), the period of gradual vegetation increase (2008 - 2013), and the period of second rapid increase (2013 - 2016). Multiple regression analysis was performed using independent variables representing hydrology, climate, and geomorphology. The major variables found to be involved in the changes in the vegetated area of the Naeseong stream were the discharge during June - July, channel width, and temperature during April - June. Among the three variables, discharge and temperature were respectively the main independent variables in the downstream and the upstream reaches as per a single variable model. Channel width was the variable that distinguished the upstream and downstream reaches of the stream. The implication of the long-term increase in the vegetated area in the Naeseong stream was discussed based on the result of this study.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.576-586
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• 2023

In this study, a numerical particle tracking experiment was conducted to assess the distribution characteristics of freshwater exclusion resulting from the discharge of Gahwa Stream into Sacheon, Jinju, and Gangjin bays, located downstream of the Namgang Dam. The number of particles discharged into Noryang Channel, Daebang Channel, and Changseon Strait was compared by releasing 1000 particles through Gahwa Stream under three discharge conditions: no discharge, discharge during rainfall, and discharge during flood. Evidently, the percentage of particles in the Noryang Channel increased, whereas that in the Daebang Channel decreased as the discharge from the Gahwa Stream increased. Approximately 95% of the material located downstream of the Gahwa Stream generally escaped through the Daebang Channel. However, as the discharge from the Namgang Dam increased due to rainfall, the percentage of particles in the Noryang Channel increased, reaching 45.5% during floods.

• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.89-97
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• 1997

Most of urban streams in Korea have been changed channel forms and suffered from direct inflow of domestic sewage, etc. Therefore, maintenance of structure and function of those ecosystem are hard. The present study was carried out to examine the life survival maintenance ability of the stream by community analysis of aquatic animals in typical urban stream (Jungrang stream) in Seoul. The aquatic animals were composed of 31 species, 18 families, 8 orders, 5 classes in 4 phyla. Seasonal species number showed big fluctuation between 8 species in Winter and 24 species in Autumn. Major dominant species in Jungrang stream were Tubificidae sp.1, Chironomidae sp.1, Chironomidae sp.2 and Physa acuta, and above endurance species for water pollution occupied very high dominance indices. But, Cercion hieroglyphicum, Ischnura asiatica, Rantra chinensis, Herochares striatus, Agabus japonicus in benthic macroinvertebrates of a few individuals are appeared. Also, fry of Carassius auratus and Silurus asotus in fish are occurred. Therefore, we can be inferred on posibility of growth and spawning of above species in the stream. Jungrang stream has a small quantity of natural riffle areas, ponds and watergrass areas by channel form of water course. Aquatic animals in Jungrang stream has been suffered by reduction of self-purification reaction ability and have mass production of attached algae on the stream bed. For analysis of fluctuation of life survival maintenance ability in Jungrang stream, long-term survey is needed.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1215-1218
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• 1998

본 논문은 Digital Audio Compression(AC-3) Standard 인 A-52를 기반으로 하였으며 Borland C++3.1 Compiler를 사용하여 AC-3 Decoding Algorithm 구현하였다. Input Stream은 DVD VOB File에서 AC-3 Stream만을 분리하여 사용하며 최종 출력은 16 Bit PCM File이다. AC-3의 Frame구조는 Synchronization Information, Bit Stream Information, Audio Block, Auxiliary Data, Error Check로 구성된다. Aduio Block 은 모두 6개의 Block으로 나뉘어져 있다. BSI와 Side Information을 참조하여 Exponent를 추출하여 Exponent Strategy에 따라 Exponent를 복원한다. 복원된 Exponent 정보를 이용하여 Bit Allocation을 수행하여 각각의 Mantissa에 할당된 Bit수를 계산하고 Stream으로부터 Mantissa를 추출한다. Coupling Parameter를 참조하ㅕ Coupling Channel을 Original Channel로 복원시킨다. Stereo Mode에 대해서는 Rematrixing을 수행한다. Dynamic Range는 Mantissa와 Exponent의 Magnitude를 바꾸는 것으로 선택적으로 사용할 수 있다. Mantissa와 Exponent를 결합하여 Floating Point coefficient로 만든 후 Inverse Transform을 수행하면 PCM Data를 얻을 수 있다. PC에서 듣기 위해서는 Multi Channel을 Stereo나 Mono로 Downmix를 수행한다. 이렇게 만들어진 PCM data는 PCM Data를 재생하는 프로그램으로 재생할 수 있다.

• Journal of Environmental Science International
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• v.13 no.1
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• pp.19-26
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• 2004

The purpose of the study was to construct a forecast system of flood inundation area at natural stream channels. The study built the system to interpret the flood inundation area in four stages ; constructing topography data around the stream channel, interpreting flood discharge, interpreting flood elevation in the stream channel, and interpreting the flood inundation and mapping. According to the result of the analysis, as for the characteristic of flood inundation around the area within the purview of this study, although there were areas where flood inundation over a bank caused a flooded area, the failure of the internal drainage in the ground lower than flood elevation caused more serious problems. Rather than the existing method where only the estimated flood elevation data is used based on the hydrographical stream channel trace model(such as the HEC-RAS model) to establish the flood inundation area, if the procedure introduced in this study was applied to interpret the floodplain, actual flood inundation area could be visibly confirmed.

• Journal of the korean society of oceanography
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• v.38 no.2
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• pp.45-51
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• 2003

Recent observations reveal that the Tsushima Current has a double-cored structure downstream of the Tsushima Island. To explain this, a simple analytical model is proposed based on the assumption of small lateral eddy viscosity. This model suggests that an otherwise uniform current becomes to have a stream core immediately after it enters a channel due to the action of lateral friction. The core is initially broad but becomes sharper downstream. The speed at which the core develops depends on the intensity of lateral eddy viscosity. Likewise, a single-cored stream changes rapidly to a double-cored stream when it passes through an island located in the center of the channel. When the stream leaves the island behind, the reverse process from the double-to single-cored structures takes place. In this case, however, the double-cored structure is retained for a significant distance from the island. Overall, this model suggests that the double-cored structure of the Tsushima Current observed downstream of the Tsushima Island Is created by the lateral friction exerted by the Tsushima Island.

• Journal of The Geomorphological Association of Korea
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• v.28 no.3
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• pp.1-11
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• 2021

The drainage area of the Miho stream is composed of granitic basins, gneissic and sedimentary mountains. 80 percent of the Miho stream flows through the Jincheon basin and the Cheongju inner-plain within the Daebo granite belt. Because the deep weathering of granitic hills provides a large amount of sands to the streams, there are wide floodplains with thick alluvium developed in the basin and plain. The thickness of the alluvium is 5~10m and the width of the floodplains is 2~2.5km. In the basin outlet area where a stream passes through the mountain canyon, wide floodplains and deep alluvium are developed in other riverside. The Miho stream is a sand-gravel channel flowing through the Cheongju inner-plain with wide floodplains and deep alluvium formed by deep weathering of granite.