• Title/Summary/Keyword: 한국 지형학회

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Generation mechanisms of coastal low level jets associated with baroclinicity along the Texas Gulf coast (텍사스 연안의에 의한 연안저층 제트의 생성 역학)

  • ChoiHyo
    • 한국해양학회지
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    • v.20 no.2
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    • pp.28-39
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    • 1985
  • The driving mechanisms for low level jets(LLJ) and coastal surface maximum winds are studied with observed wind data from June, 1976 through August, 1980 at Port Aransas and Victoria, Texas, in connection with a baroclinic model. This model is developed considering the forcing functions such as the synoptic and meso-scale pressure gradient, the frictional force, and the atmospheric stability. The results show that a LLJis observed on over 95% of the occasions when a nighttime coastal wind maximum occurred. Baroclinicity generated by sloping terrain during the summertime causes the diurnal variation in the thermal field. This thermal wind component would then decrease the prevailing synoptic-scale southerly wind by day and allow it to increase at night. Nighttime atmospheric stability leads to frictional decoupling which enhances the nocturnal LLJ. At the coastal site neutral stability prevails, thus all owing downward transfer of momentum from the nocturnal LLJ and results in the nocturnal coastal surface wind maximum. The height of LLJis not uniquely related to the inversion layer, and the results of the computations using this model show a good agreement with the observations.

Treatment of hazardous chemicals by Nanoscale Iron powder (나노크기 철 분말을 이용한 난분해성 유해화합물질의 처리)

  • 최승희;장윤영;황경엽;김지형
    • Journal of Korea Soil Environment Society
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    • v.4 no.3
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    • pp.85-93
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    • 1999
  • The destruction of hazardous chemicals such as chlorinated organic compounds(COCs) and nitroaromatic compounds(NACs) by zero-valent iron powder is one of the latest innovative technologies. In this paper. the rapid dechlorination of chlorinated compounds as well as transformation of nitro functional group to amine functional group in the nitroaromatic compounds using synthesized zero-valent iron powder with nanoscale were studied in anaerobic batch system. Nanoscale iron, characterized by high surface area to mass ratios(31.4$\textrm{m}^2$/g) and high reactivity, could quickly reacts with compounds such as TCE, chloroform, nitrobenzene, nitrotoluene, dinitrobenzene and dinitrotoluene, at concentration of 10mg/L in aqueous solution at room temperature and pressure. In this study, the TCE was dechlorinated to ethane and chloroform to methane and nitro groups in NACs were transformed to amino groups in less than 30min. These results indicated that this chemical method using nanoscale iron powder has the high potential for the remediation of soils and groundwater contaminated with hazardous toxic chemicals including chlorinated organic compounds and nitro aromatic compounds.

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Isolation and Characterization of Morganella morganii from Asian Water Monitor Varanus salvator (아시아 물왕도마뱀에서 분리된 모가넬라 모가니의 분리동정)

  • Shin, Sang-Phil;Kim, Ji-Hyung;Gomez, Dennis K.;Choresca Jr., Casiano H.;Han, Jee-Eun;Park, Se-Chang
    • Journal of Veterinary Clinics
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    • v.26 no.4
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    • pp.391-394
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    • 2009
  • An Asian water monitor Varanus salvator with physical wound due to bite which was subsequently infected with bacterium resulting to hemorrhage and pus in the skin blisters, abdominal distention and septicemia. Morganella morganii was isolated and identified from the blood and kidney of the reptile, and confirmed by PCR and biochemical tests. The sensitivity of isolated strains to different groups of antibiotics was also evaluated using the disc diffusion method. Pathogenicity test using M. morganii (SNUFPC-MM01) (1.6 ${\times}$ $10^{11}$CFU/mouse) to suckling and adult mice resulted to the death of all mice. This paper describes the first isolation of M. morganii from Asian water monitor in Korea.

Improvement of Water Quality and Streamflow Monitoring to Quantify Point and Nonpoint Source Pollutant Loads (점오염원과 비점오염원 부하량 정량화를 위한 수질 유량 모니터링 개선)

  • Jang, Ju-Hyoung;Lee, Hyung-Jin;Kim, Hyun-Koo;Park, Ji-Hyoung;Kim, Ji-Ho;Rhew, Doug-Hee
    • Journal of Korean Society on Water Environment
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    • v.26 no.5
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    • pp.860-870
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    • 2010
  • Long term monthly monitoring data showed that the water quality of streams flowing into Lake Paldang has been improved by various strategy for water. However, the effect of quality on Lake Paldang is still insufficient because of nonpoint source from watershed. In order to evaluate quantifying methods for pollution source and make a suggestion on improvements, Storm Water Management Model (SWMM) was constructed by using data set from the water quality and streamflow monitoring network in the Kyoungan watershed for Total Maximum Daily Loads (TMDLs). Load duration curve (LDC) based on the result of the Kyoungan watershed SWMM indicated that the water quality criterion on $BOD_5$ was often exceeded in up-stream than down-stream. From flowrate-load correlation curve, SS load significantly increased as streamflow increases. 75.3% of streamflow and 62.1% of $BOD_5$ loads is discharged especially in the zone of high flows, but monitoring data set didn't provide proper information about the conditions and the patterns associated with storm events. Therefore, it is necessary to acquire representative data set for comparing hydrograph and pollutograph through monitoring experimental watershed and to establish methods for quantifying point and nonpoint source pollutant loads.

Functional Assessment of Yongdam Dam-wetland by HGM (HGM을 이용한 용담댐습지의 기능평가 연구)

  • Kim, Duck-Gil;Shin, Han-Kyu;Kim, Jae-Geun;Kim, Hung-Soo;Yoo, Byong-Kook;Ahn, Kyung-Soo;Jang, Seok-Won
    • Journal of Wetlands Research
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    • v.13 no.3
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    • pp.665-675
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    • 2011
  • Dam as a Wetland can provide functions of ecological conservation, water quality improvement, landscape, and so on as well as. Dam's own various functions. Here we tried to assess function and value of Yongdam dam as a wetland by Hydrogeomorphic(HGM) Method which was developed by U.S. Army Corps of Engineers. In this study, the Upo wetland and Boryeong dam were selected as reference wetlands to assess the functional index of the Yongdam dam. As the results, we obtained the functional index values over 0.6 for total index of the Yongdam dam. It describes that Yong dam dam-wetland is providing over 60% functions of the Upo wetland and Boryung dam-wetland. This result suggests that dam-wetland can provide good wetland functions efficiently if we conserve and manage well.

A Study on the Estimation of Soil Erosion Quantity Using USLE in the Upper Region of ManKyoung River Basin (USLE를 활용한 만경강 상류지역에서의 토양침식량 산정에 관한 연구)

  • Lee, Jae Hyug;Shim, Eun Jeung;Lee, Yeon Kil;Kim, Tae Woong
    • Journal of Wetlands Research
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    • v.14 no.3
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    • pp.317-328
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    • 2012
  • The objects of this study are to perform appropriateness analysis of USLE(universal soil loss equation) model and to accumulate the data measured in field. The basin area of Bongdong station is $342.27km^2$. This study simulated sediment outflows in the basin and performed a comparative analysis of simulated outputs with actual measurement values. Also annual rainfall was used to calculate rainfall-runoff erosivity factor which can influence soil erosion. The calculation of annual average soil erosion was made by soil erosion maps. The maps with a resolution of ($30m{\times}30m$) were created by multiplication of factors(R, LS, K, C, P) from ArcView Map Calculator. In this paper, it was shown that soil erosion was not occur in the most of basin.

3D Stereo Display of Spatial Data from Various Sensors (다양한 센서로부터 획득한 공간데이터의 3D 입체 디스플레이)

  • Park, So-Young;Yun, Seong-Goo;Lee, Young-Wook;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.6
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    • pp.669-676
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    • 2010
  • Visualization requires for effective analysis of the spatial data collected by various sensors. The best way to convey 3D digital spatial information which is modeling of the real world to the users, realistic 3D visualization and display technology. Since most of the display is based on 2D or 2.5D projection to the plane, there is limitation in representing real world in 3D space. In this paper, data from airborne LiDAR for topographic mapping, Flashi-LiDAR as emerging sensor with great potential to 3D data acquisition, and multibeam echo-sounder for underwater measurement, were stereoscopically visualized. 3D monitors are getting popular and could be information media and platform in geoinformatics. Therefore, study on creating 3D stereoscopic contents of spatial information is essential for new technology of stereo viewing systems.

Pheontypic Characterization of Non-molting Mutants in Postembryonic Development of the Silkworm, Bomyx mori. (누에의 후배자발생 초기에 있어서 돌연변이 불면잠계통간의 형질발현 특성)

  • No, Si-Gap;Seon, Hui-Suk;Banno, Yutaka
    • Journal of Sericultural and Entomological Science
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    • v.40 no.1
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    • pp.43-51
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    • 1998
  • Studies were carried out to investigate phenotypic expression, mortality and biochemical analysis of haemolymph proteins of nm-d, nm-f, nm-k and nmn bib-molting mutants of the silkworm, Bombyx mori. The non-molting mutants characters were expressed in the homozygote of each mutant genes. All strains of non-molting mutants were similar with each other in physiological characteristics, but the expression varied with each strains. The larvae of nm-d, nm-i and nmn died between day 5 and day 9 after hatching without the first molt. The nm-f and nm-k mutants died between day 5 and day 16 with a slight increase of body weight and, more than 90% of the mutants larvae died before the first molt and a few of them survived to the 2nd and the 3rd instar and died. The haemolymph protein components of nm-d, nm-i, and nmn were rapidly reduced, and on the other hand those of nm-f and nm-k consistently until they died. And there were no distinguishable difference in haemolymph components of non-molting mutants, as compared to those normals.

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Stabilization of As in Soil Contaminated with Chromated Copper Arsenate (CCA) Using Calcinated Oyster Shells (목재방부제(CCA) 오염토양의 소성가공 굴껍질을 이용한 비소 안정화)

  • Moon, Deok-Hyun;Cheong, Kyung-Hoon;Kim, Tae-Sung;Khim, Jee-Hyeong;Choi, Su-Bin;Moon, Ok-Ran;Ok, Yong-Sik
    • Korean Journal of Environmental Agriculture
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    • v.28 no.4
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    • pp.378-385
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    • 2009
  • Arsenic (As) is known to be very toxic and carcinogenic to human beings. Arsenic contaminated soil was collected from a timber mill site at Busan Metropolitan City, Korea, where chromated copper arsenate (CCA) had been used to protect wood from rotting caused by insects and microbial agents. The soil was stabilized using both natural oyster shells (NOS) and calcinated oyster shells (POS). The calcination of natural oyster shells was accomplished at a high temperature in order to activate quicklime from calcite. Two different oyster shell particle sizes (-#10 mesh and -#20 mesh) and curing periods of up to 28 days were investigated. The stabilization effectiveness was evaluated based on the Korean Standard Test (KST) method (1N HCl extraction). The stabilization results showed that the POS treatment was more effective than the NOS treatment at immobilizing the As in the contaminated soils. A significant As reduction (96%) was attained upon a POS treatment at 20 wt% and passed the Korean warning standard of 20 mg/kg ('Na' area). However, an As reduction of only 47% (169 mg/kg) was achieved upon a NOS treatment at 20 wt%. The -#20 mesh oyster shells seem to perform better than the -#10 materials. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that As immobilization was strongly associated with Ca and O in the presence of Al and Si.

Formation and Variation of Turbidity Maximum in the Neuse River Estuary, North Carolina, U.S.A. (Neuse강 하구의 최대혼탁수 형성과 변동)

  • KIM Seok-Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.6
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    • pp.754-770
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    • 1994
  • Suspended sediment distribution and water column processes in the upper Neuse River estuary, North Carolina, were monitored monthly from February 1988 through February 1989, in order to identify the turbidity maximum, to determine its temporal and spatial variation under changing conditions(freshwater runoff, wind, and tide). During most of the observation periods a weak turbidity maximum, associated with the estuarine circulation processes, developed at a flow convergence zone, near the upstream limit of salt intrusion. No turbidity maximum was found when the water column was vertically homogeneous with respect to salinity and when there was no consistent upstream bottom flow. Annual migration of the turbidity maximum, accompanied by migration of salt intrusion, was over 20 km of the upper estuary. Due to the coincidence of dominant wind direction(NE-SW) with the main orientation of the Pamlico-Neuse system, wind played the dominant role in dynamics of the turbidity maximum by influencing the degree of salinity stratification and the extent and strength of estuarine circulation. Tidal effects on the sediment dynamics were negligible.

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