팔당호 연안생태계의 수생식물상과 생태적 특성

임용석,마선미,나성태,최홍근,신현철 한국육수학회 2005 생태와 환경 Vol.38 No.1

팔당호 연안대의 수생식물상과 식생을 파악하기 위하여 2003년 4월부터 2004년 4월까지 9곳의 조사 지점을 선정하여 선방형구법을 이용하여 조사하였다. 팔당호 연안대에는 128종류의 관속식물이 생육하고 있는 것으로 조사되었고, 이중 수생식물은 38종류였다. 수생식물의 경우 정수식물이 21종류로 가장 많았고, 침수식물은 8종류 였고, 침수식물 종류수는 이전 조사보다 감소한 것으로 파악되었다. 팔당호 주요 식생은 애기부들, 줄, 갈대가 우점하는 정수식물대로 파악되었고, 특히 두물머리, 광동교 근처에 넓게 정수식물대가 넓게 발달하였다. 귀화식물은 11종류가 분포하고 있었으나, 출현 빈도는 상대적으로 높았다. 팔당호 연안대에 분포하는 식물의 출현 빈도를 조사 지점을 기준으로 살펴보면, 조사 지점당 수생식물은 2.7종류, 습생식물은 2.5종류, 육지식물은 1.8종류로 파악 되었고, 수직대상분포 식생이 팔당호 연안대에서 발견되었다. 이러한 조사 결과는 팔당호 연안대가 수생태계의 전형적인 특성들을 지니고 있는 것으로 풀이된다. To investigate the flora and vegetation structure of vascular plants in the littoral zone of Paldang Reservoir, from April, 2003 to April 2004, nine sampling sites were selected. Along the Paldang Reservoir, 128 taxa, consisted of 51 families and 96 genera, were identified, among them, hydrophytes were confirmed as 38 taxa, which was comprised 29.7% to total taxa, whereas hygrophytes were 44 taxa and terrestrial plants were 46 taxa. Emergent hydrophytes consists of 21 taxa, including Phragmites australis and Typha angustifolia, and next, submerged hydrophytes were 8 taxa. However, the kinds and vegetation area of submerged hydorphytes were reduced compared to previous studies. In the littoral zone of Paldang Reservoir, the aquatic vegetation was widely developed near Dumulmori, Yangsuri, and Kwangdong Bridge, downstream of Kyungancheon. The average number of hydrophyte per sampling sites were 2.7 taxa, whereas hygrophytes were 2.5, and land plants were 1.8. In addition, the hydrophytes in the littoral zone of Paldang Reservoir showed the typical vertical zonation pattern like a natural swamp. These results mean that the littoral zone of Paldang Reservoir has the typical characteristics of aquatic plant ecosystem.

Application of diffusive gel-type probes for assessing redox zonation and mercury methylation in the Mekong Delta sediment

Hong, Yongseok,Dan, Nguyen Phuoc,Kim, Eunhee,Choi, Hyo-Jung,Han, Seunghee The Royal Society of Chemistry 2014 Environmental science Vol.16 No.7

<P>The vertical profiles of PO43-, Mn, Fe, S2-, Hg, and CH3Hg+ in sediment pore water were investigated using DGT and DET probes in the Tien River, the northern branch of Vietnam's Mekong Delta. Although some of the DGT measurements could be lower than the actual pore water concentrations due to the depletion of the species, the measurements provided information for understanding redox zonation and Hg methylation. The gradual increases in the measured species concentrations with the sediment depth were observed and the diffusive fluxes of the species to overlying water were expected. The vertical profiles suggested that (1) SO42- seemed to be reduced before Fe3+, or the two electron acceptors were reduced simultaneously; (2) the release of PO43 was more closely related to S-2 than Fe release; and (3) Hg methylation was active in the micro-niche between the aerobic and anaerobic transition zones. The maximum pore water CH3Hg+ concentrations were observed at depths just above where the maximum S2- concentrations were detected. Hence, the maximum CH3Hg+ concentration was observed near surficial sediments (less than 1 cm from the surface) in brackish water, and at a depth of 3 cm in fresh water. The different vertical profiles led to a CH3Hg+ diffusive flux eight-times greater in brackish than in fresh water. The present study showed that the in situ application of DGT and DET probes was helpful to understand coupled biogeochemical reactions and mercury methylation by measuring pore water redox species.</P>

베트남 메콩강 유역의 티엔강 퇴적물 공극수에서 존인농도 측정을 위한 박막분산탐침 적용

홍용석(Yongseok Hong),임지혜(Lim Jihye),이동학(Lee Donghak),얀 뉘엔 푸옥(Nguyen Phuoc Da),노샘(No Seam),카심 굴람 후세인(Ghulam Hussain Qasim),김은석(Eunseok Kim),한승희(Seunghee Han) 적정기술학회 2015 적정기술학회지(Journal of Appropriate Technology) Vol.1 No.1

퇴적토에서 유해오염물질 거동 및 모니터링 방법

홍용석 ( Hong Yongseok ) 한국물환경학회(구 한국수질보전학회) 2018 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2018 No.-

가축분뇨실태조사를 위한 우선 조사 대상지역 선정 방안 도출

류홍덕 ( Hong Duck Ryu ),박배경 ( Bae Kyung Park ),정유진 ( Eu Gene Chung ),안기홍 ( Ki Hong Ahn ),최원식 ( Won Sik Choi ),김용석 ( Yongseok Kim ),류덕희 ( Doughee Rhew ) 한국환경과학회 2015 한국환경과학회지 Vol.24 No.8

The purposes of this study were to suggest the methodology to select prior areas in the environmental pollution survey for livestock excreta (EPSLE) as well as to elucidate the validity of the methodology. In this study, the prior areas in the EPSLE were determined by examining the number of compost facilities categorized according to the three levels of size including the basin, the sub-basin and the watershed, respectively, based on the data from “Annual Nation-wide Pollution Sources Survey (2012)”. The results suggested that the list of prior basins were Nakdong, Geum, Youngsan and Han river basins in order. Also, it was examined that the prior sub-basins in the four river basins including Nakdong, Geum, Youngsan and Han rivers were Naesung Stream, Geumgang Gongju, Juam Dam and Namhan Downstream, respectively. The prior watersheds in the sub-basins of Naesung stream, Geumgang Gongju, Juam Dam and Namhan Downstream were Seocheon Downstream, Geum Stream, Gyeombaek Suwipyo and Yanghwa Stream, respectively. The validity of the methodology used in this study was elucidated by analyzing the correlation of the number of compost facilities with the concentrations of T-N and T-P observed in the end-points of sub-basins. The results of correlation analysis showed that the concentrations of T-N and T-P increased with the number of compost facilities. Specifically, there was the stronger correlation between the number of compost facilities and the concentrations of T-N than that for T-P. Consequently, it was proved that the methodology used in this work was valid and rational for the selection of prior areas in environmental pollution survey for EPSLE.

가축분뇨로부터 struvite 결정화에 의한 질소 (N), 인 (P) 회수 및 자원화 방안 고찰

류홍덕 ( Hong-duck Ryu ),안기홍 ( Ki Hong Ahn ),정유진 ( Eu Gene Chung ),김용석 ( Yongseok Kim ),류덕희 ( Doughee Rhew ) 한국환경과학회 2017 한국환경과학회지 Vol.26 No.1

This study evaluated the feasibility of recovering and recycling nitrogen (N) and phosphorus (P) from livestock excreta as struvite (MgNH₄PO₄·6H₂O) in South Korea. Our experimental results showed that struvite precipitation was a very effective way to recover N and P from livestock excreta. Moreover, our study demonstrated that struvite precipitates from livestock excreta (SPL) contain higher concentrations of N, P, and magnesium (Mg) as compared to compost and liquid manure from livestock excreta. In addition, although SPL contain high concentrations of copper (Cu) and zinc (Zn), they meet the fertilizer criteria for concentrations of heavy metals. In South Korea, SPL cannot currently be used as a fertilizer due to legal constraints. Legal permission for SPL use would offer greater choice in livestock excreta management. In conclusion, recovery and recycling of N and P from livestock excreta as struvite can be an effective tool for managing nutrients in livestock excreta.

3D환경에서 계층적 정보의 조작을 위한 제스처 인터랙션

홍용석(Yongseok Hong),최용순(Yongsoon Choi) 한국HCI학회 2017 한국HCI학회 학술대회 Vol.2017 No.2

족보와 같은 계층적 정보는 하위단계로 갈수록 정보의 양의 급격한 증가를 보이기 때문에 이를 효율적으로 시각화하기 위한 다양한 방법론이 제시되었다. 콘 트리 다이어그램(Cone Tree Diagram)과 같이 3차원 구조의 시각화 방법도 제시되어 왔지만 이는 2차원 화면에 3차원 구조를 재현한 것에 지나지 않았다. 본 연구는 가상현실(VR)과 같이 3차원 구조의 그래픽을 입체적으로 인식할 수 있게 하는 기술의 환경에서, 3차원 구조로 구축된 계층적 정보에 사용자가 접근, 조작하는데 있어 제스처 인터랙션에 대해 사용자 조사를 진행하였고, 대부분의 사용자들이 기존에 사용해온 컴퓨터와 모바일 디바이스의 제스처 인터랙션과 비슷한 멘탈모델을 공유하고 있으며, 가상공간 내의 3차원의 정보구조에 대한 인식에 있어 사용자 간의 차이를 보여주었다.

Photometric Properties of the HW Vir-type Binary OGLE-GD-ECL-11388

Hong, Kyeongsoo,Lee, Jae Woo,Lee, Dong-Joo,Kim, Seung-Lee,Koo, Jae-Rim,Park, Jang-Ho,Lee, Chung-Uk,Kim, Dong-Jin,Cha, Sang-Mok,Lee, Yongseok Astronomical Society of the Pacific 2017 Publications of the Astronomical Society of the Pa Vol.129 No.971

<P>We present the first extensive photometric results for the eclipsing binary OGLE-GD-ECL-11388 with a period of about 3.5 hours located in the Galactic disk. For the photometric solutions, we obtained the BVI light curves from both the KMTNet observations in 2015 and the OGLE -III survey data from 2001-2009, which show striking reflection effects and very sharp eclipses. The light curve synthesis indicates that the eclipsing system is a HW Virtype binary with a mass ratio of q = 0.289, an orbital inclination of i = 81.9 deg, and a temperature ratio between both components of T-2/T-1 = 0.091. A frequency analysis was applied to the light residuals from our binary model; however, no pulsating periodicity from the subdwarf B -type primary component was detected under signal-tonoise amplitude ratios larger than 4 0 A total of 27 minimum epochs spanning 15 yr were used to analyze the eclipse timing variations of OGLE-GD-ECL-11388. It was found that the orbital period has varied due to a continuous period decrease at a rate of dP/dt = -1.1 x 10(-8) day yr(-1) or a sinusoidal oscillation with a semiamplitude of K = 35 s and a cycle of P-3 = 8.9 yr. The period decrease may be explained by an angular momentum loss via magnetic stellar wind braking or may be only a part of the sinusoidal variation. We think the most likely interpretation of the orbital period change, at present, is the light -time effect via the presence of a third body with a mass of M-3 sin i(3) = 12.5 M-Jup, putting it in the boundary zone between planets and brown dwarfs.</P>

Maintenance and Improvement of KMTNet Telescope and Enclosure

Yongseok Lee,Sang-Mok Cha,Chung-Uk Lee,Seung-Lee Kim,Dong-Joo Lee,Young-Beom Jeon,Hong Soo Park,Ho Jin 한국천문학회 2018 天文學會報 Vol.43 No.1

안드로이드 기반 스마트폰의 사용자 응답성 향상을 위한 프레임워크 지원 우선순위 부스트 기법과 로드 밸런싱 기법

손용석(Yongseok Son),허승주(Sungju Huh),유종훈(Jonghun Yoo),홍성수(Seongsoo Hong) 한국정보과학회 2012 정보과학회논문지 : 시스템 및 이론 Vol.39 No.6

최근 안드로이드 플랫폼을 탑재한 스마트폰이 널리 보급되면서 안드로이드 플랫폼에 대한 관심은 더욱 커지고 있다. 하지만 안드로이드 스마트폰은 종종 양질의 사용자 응답성을 제공하지 못하는 것으로 알려져 있다. 이는 안드로이드 상에서 대화형 태스크가 다른 태스크와 구별되지 않고 동일한 우선순위로 스케줄링 되기 때문에 사용자 입력을 처리하는 동안 여러 번의 선점을 당해 긴 응답시간을 초래할수 있기 때문이다. 이 논문은 안드로이드 스마트폰의 사용자 응답성 향상을 위해 프레임워크 지원 우선순위 부스트 기법과 로드 밸런싱 기법을 제시한다. 프레임워크 지원 우선순위기법은 프레임워크 레벨에서 대화형 태스크를 식별하고 이를 커널에게 전달하며, 커널 레벨에서는 식별된 태스크의 우선순위를 선별적으로 부스트 시킴으로써 사용자 입력을 처리할 만큼 충분한 시간을 보장해 준다. 로드 밸런싱 기법은 부스트 된 태스크를 여전히 방해하는 태스크들을 다른 실행 큐로 이주시킴으로써, 대화형 태스크의 응답시간을 최소화 한다. 실험 결과 대화형 태스크의 응답시간이 우선순위 부스트 기법을 통해서는 기존 시스템보다 최대 22% 단축됨을 보였고 로드 밸런싱 기법을 통해서는 최대 43.31% 단축됨을 보여 제안된 기법의 효용성을 입증하였다. Smartphones on Android platform recently have been come into wide use. However, it is often reported that Android smartphones cannot provide enough interactivity because Android cannot distinguish interactive tasks and non-interactive tasks and they are scheduled with the same priority and preempted. Thus, it occurs poor response time. This paper proposes a framework assisted priority boosting and load balancing for improving interactivity of Android smartphones. The framework assisted priority boosting technique distinguishes the interactive task in the framework level and send the task ID to the kernel. The kernel ensures enough time to process user input by boosting the priority of distinguished task. The load balancing technique minimizes response time of boosted task by migrating tasks disturbing boosted task to other run-queue. The experiment results demonstrate the priority boosting technique reduces response time up to 22% and the load balancing technique along with priority boosting reduces response time up to 43.31% compared to the previous techniques.