• 한국물환경학회지
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• 제26권6호
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• pp.903-909
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• 2010

The purpose of this study was evaluated on the applicability of Load Duration Curve Method (LDC Method) using HSPF watershed model and sampling data for efficient TMDLs in Korea. The LDC Method was used for assessment pollutant characteristics in watershed and water quality variation in each water flow level. Load Duration Curve is applied for judge the level of impaired water-body and can be estimated the impaired level by pollutant, such as BOD, T-N, and T-P in this study depending on variation of stream flow. As a result, BOD, T-P was usually exceed the standard value at low flow and dry hydrologic period. Improvement of effluent concentration from WWTP and riparian buffer protection zone are effective to improve the water quality. T-N showed the worst condition at mid-range hydrologic period and moist hydrologic period. Therefore, soil erosion control program and BMPs for non-point source pollution control is effective for recovery the water quality, which can be useful method for management of water quality in the plan of recovery water quality spontaneously. Applicability of LDC Method was evaluated in the Nakbon A watershed. However, we need to consider more detailed and accumulated data set such as accurate GIS data and detail pollution data, and WWTP discharge water quality data for accurate evaluation of watershed. Overall, The LDC Method is adequate for evaluation of watersheds characteristics, and its application is recommended for watershed management and TMDL Implementation.

• 한국재료학회지
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• 제19권10호
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• pp.517-521
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• 2009

Si-C composite with hollow spherical structure was synthesized using ultrasonic treatment of organosilica powder formed by hydrolysis of phenyltrimethoxysilane. The prepared powder was pyrolyzed at various temperatures ranging from 900 to 1300 $^{\circ}C$ under nitrogen atmosphere to obtain optimum conditions for Li-ion battery anode materials with high capacity and cyclability. The XRD and elemental analysis results show that the pyrolyzed Si/C composite at 1100 $^{\circ}C$ has low oxygen and nitrogen levels, which is desirable for increasing the electrochemical capacity and reducing the irreversible capacity of the first discharge. The solid Si-C composite electrode shows a first charge capacity of $\sim$500 mAhg$^{-1}$ and a capacity fade within 30 cycles of 0.93% per cycle. On the other hand, the electrochemical performance of the hollow Si-C composite electrode exhibits a reversible charge capacity of $\sim$540 mAhg$^{-1}$ with an excellent capacity retention of capacity loss 0.43% per cycle up to 30 cycles. The improved electrochemical properties are attributed to facile diffusion of Li ions into the hollow shell with nanoscale thickness. In addition, the empty core space provides a buffer zone to relieve the mechanical stresses incurred during Li insertion.

• 대한토목학회논문집
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• 제36권1호
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• pp.169-180
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• 2016

항구도시에서 항만과 도시공간은 상이한 공간특성을 가지고 있지만 서로 상호의존적으로 발전되어 나가야 한다. 기능쇠퇴로 인한 기존 공간의 장소성 상실과 기능 저하는 도시 전체의 이미지를 나쁘게 만들 뿐만 아니라 나아가 지역 경제부흥에도 좋지 않은 영향을 미치고 있다. 이에 일부 선진국에서는 시대변화에 따른 항만공간 특성 및 기능의 변화로 인해 낙후되어가는 항만공간에 대한 연구를 오래전부터 지속적으로 진행해 오고 있다. 본 연구에서는 항만배후단지에 항만과 도시공간 사이의 완충지 역할을 할 수 있는 항만도시 인터페이스 공간의 특성 적용하여 향후 국내 항만배후단지가 주변 공간특성과 항만도시 인터페이스 특성이 부여된 효율적인 공간으로 활용되기 위한 방안을 모색하고자 한다.

• 한국조경학회지
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• 제33권2호
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• pp.71-82
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• 2005

A large scale of riverside rearrangement has been recently done in the major rivers in Korea. So inundation possibility in agricultural area closed by these rivers has been higher than the possibility a few years ago. However, land use in this area has not been adjusted to a change of this situation near the rivers. Therefore, when typhoon or heavy rain is happened on this area, it can cause a large damage in agricultural area. This study analyzed inundation potentiality in agricultural area at Ibang-myeon, Changnyeong-gun, Kyeongnam-province, Korea by using the logistic regression model and the piecewise regression model. The first thing we did was to transfer the inundation area per elevation to the accumulated inundation area per elevation. This accumulated inundation area per elevation as an distribution function could be described by the logistic regression model(LRM), and piecewise regression model(PRM) could make it much more accurate to analyze the inundation area per elevation. As a result, the regression models derived from LRM and PRM showed $R^2$ over 0.950. The models derived from LRM and PRM in Ibang-myeon noted that frequently inundated area(FIA) was shown up to 12.12m in elevation, and potentially inundated area(PIA) was shown up to 14.60m in elevation. In FIA, regular agricultural activity would be impossible. And It would be not easy to continue the regular agricultural activity in PIA. So, this land should be rearranged to be used for a buffer zone for ecosystem protection, landscape conservation and things like that in riverside.

• 한국환경복원기술학회지
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• 제16권4호
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• pp.1-14
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• 2013

A species restoration plan requires a process where the first is to thoroughly study the target species, second is to provide them with an onsite reproduction and adaptation period, and finally, third is to release them to their natural habitat. This study focuses on the space planning for target species' successful onsite reproduction and adaptation. For the study, a site planning near Sobaeksan National Park was implemented with Red Fox's behavior and habitat characteristics in mind for its recovery, reproduction, and natural adaptation. During site selection and planning, the basic aim was to incorporate the existing site as much as possible thus reducing the impact on the environment from the recovery plan. In addition, for a stable recovery of the Red Fox population, the site was classified into three different areas : core area, buffer zone, and transition area. Then, the facilities that help Red Fox's reproduction and adaptation such as reproduction center, foraging site, adaptation training center were planned. Under the condition that the site will be off limit to the public, a limited number of paths for monitoring was provided. For the site's vegetation, the existing species were planted as much as possible with the addition of plants that the Red Fox consume. The facilities included as Red Fox's habitat were fox burrows for hiding and ecological ponds for drinking. From this study, the recovery of the endangered fox species is expected as well as the contribution to an effort to increase of awareness toward the biological resources in Korea through Nagoya protocol. Furthermore, it has the potential to change the public's attitude toward endangered species recovery projects through publicizing and providing experience to the national park visitors.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.521-526
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• 2012

It is essential for the accurate time-domain prediction of broadband noise due to turbulence-cascade interaction to develop inflow/outflow boundary conditions to satisfy the following three requirements: to maintain the back ground mean flow, to nonreflect the outgoing disturbances and to generate the specified input gust. The preceding study(1) showed that Perfectly Matched Layer (PML) boundary condition was successfully applied to absorb the outgoing disturbances and to generate the specified gust in the time-domain computations of broadband noise due to interaction of incident gust with a cascade of flat-plates. In present study, PML boundary condition is extended in order to predict steady mean flow that is needed for the computation of noise due to interaction of incident gust with a cascade of airfoils. PML boundary condition is originally designed to absorb flow disturbances superimposed on the steady meanflow in the buffer zone. However, the steady meanflow must be computed before PML boundary condition is applied on the flow computation. In the present paper, PML equations are extended by introducing source term to maintain desired mean flow conditions. The extended boundary condition is applied to the benchmark problem where the meanflow around a cascade of airfoils is predicted. These illustrative computations reveal that the extended PML equations can effectively provide and maintain the target meanflow.

• 한국소음진동공학회논문집
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• 제22권7호
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• pp.685-691
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• 2012

It is essential for the accurate time-domain prediction of broadband noise due to turbulence-cascade interaction to develop inflow/outflow boundary conditions to satisfy the following three requirements: to maintain the back ground mean flow, to nonreflect the outgoing disturbances and to generate the specified input gust. The preceding study showed that perfectly matched layer(PML) boundary condition was successfully applied to absorb the outgoing disturbances and to generate the specified gust in the time-domain computations of broadband noise due to interaction of incident gust with a cascade of flat-plates. In present study, PML boundary condition is extended in order to predict steady mean flow that is needed for the computation of noise due to interaction of incident gust with a cascade of airfoils. PML boundary condition is originally designed to absorb flow disturbances superimposed on the steady meanflow in the buffer zone. However, the steady meanflow must be computed before PML boundary condition is applied on the flow computation. In the present paper, PML equations are extended by introducing source term to maintain desired mean flow conditions. The extended boundary condition is applied to the benchmark problem where the meanflow around a cascade of airfoils is predicted. These illustrative computations reveal that the extended PML equations can effectively provide and maintain the target meanflow.

• 한국실내디자인학회논문집
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• 제20권4호
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• pp.74-82
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• 2011

All the phenomena and subjects of nature and society are within correlation interconnection, and they are inseparably connected one another. The elements of this interaction can be found out through the concept of transparency in the space composition of Korean traditional architecture. This study is focusing on the access space, in other words, a gate-house that is a buffer zone playing a process role up to the main space among successive spaces. It was chosen to be the subject of the study since it strengthens convergence into the main building and with the effect connecting spaces, it could show well the spatial possibility of transparency. Besides, the subject of the study is limited to the Moonru Multi roofs that improves the functionality of spaces between gate-houses, and it is intended to progress contents by comparative analysis of two kinds such as Seo Won gate-house and temple gate-house. Korean traditional architecture places emphasis on harmony within the whole spaces. There are intimate relations between surrounding environment, external spaces and internal spaces, and it is important understand the spatial relations according to the shape appearing through interactions of parts in the whole spaces. In conclusion, the Moonru Multi roofs is analyzed with the method of extracting the concept that is contained in the frame of analysis and through ecological views through a visible and structural method. It can be understood what kinds of method for communication were used for ancestors to recognize and use spaces with the deduced concept through the analysis of the Moonru Multi roofs with different character.

• 한국멀티미디어학회논문지
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• 제13권1호
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• pp.38-46
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• 2010

P2P온라인 게임 시스템에서 대규모 사용자의 동시 접속을 수용할 수 있는 안전한 게임 운영 시스템이 필수적이다. 본 논문에서 제안하는 P2P 온라인 게임 시스템은 RS(Region Sever)들의 재구성 및 RS간의 숭호 정보 교환을 통해 한 영역에 플레이어가 집중되는 현상을 피하여 대규모 플레이어를 수용할 수 있으며, 안전한 게임을 운영할 수 있다. 또한 모니터링 서버의 광역 버퍼(Global Zone Buffer)를 이용한 부하분산으로 타임스탬프 시간 내의 게임 동기화가 가능하며고 미들웨어를 단위 영역별로 관리하여 게임 월드의 크기에 관계없이 수행 가능하다. 따라서, 서버 추가 문제의 해결 및 메시지 전송의 안정성을 확보할 수 있다. 또한, 시뮬레이션을 통하여 제안 시스템에 대한 효율성을 입증한다.

• 한국습지학회지
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• 제7권4호
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• pp.81-88
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• 2005

2001년부터 2004년동안 4년간에 걸쳐 조사된 태화강하류의 겨울철새는 11목 21과 58종 최대 출현개체수는 14,034개체이다. 연도별로 출현 사항을 보면 종수의 경우 2001년 48종에서 2004년 31종으로 매년 줄어들고 있다. 한편 개체수의 경우 2002년에 11,991개체로 가장 많이 조사되었고 2004년이 3,476개체로 가장 적게 조사되었다. 5% 이상의 우점종은 흰죽지 Aythya ferina(6,946개체), 떼까마귀 Corvus frugilegus(1,643개체), 붉은부리갈매기 Larus ridibundus(1,193개체), 괭이갈매기 Larus crassirostris(805개체)로서 이들 4종의 개체수 합(10,587개체)이 전체 개체수의 75.4%를 차지한다. 태화강에 도래하는 조류를 보호하기 위해서는 강변 가까운 곳에 조류들의 먹이장소 조성, 쉼터 등 완충지대를 만들어주고 도로와 고수부지 사이는 수목대 또는 차광대와 방음벽을 설치할 필요가 있다. 무엇보다도 시민들의 철새에 대한 보호 의지가 강해야 한다. 또한 철새들이 많이 도래하는 태화강과 동천의 합수부 일대, 조류들의 번식지와 잠자리로 이용하는 대밭 지역($2{\times}0.1km^2$)의 서식지 보호 및 관리방안이 필요하다.