• 대한환경공학회지
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• 제31권11호
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• pp.1007-1018
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• 2009

Hydrocyclone은 높은 수면적부하율 운전이 가능하고, 구동부분이 없고, 운전 및 유지관리비가 적게 소요되어 미세입자물질제거에 효과적인 장치로 다양한 산업 분야에서 활용되고 있다. Hydrocyclone에 나선형 유입부를 통해 직각으로 유입되어 중력이 아닌 원심력에 의해 입자물질이 하부배출구로 분리되고 처리수는 vortex finder를 통해 배출된다. 입자분리에 hydrocyclone은 많은 장점을 가지고 있음에도 불구하고 도시지역 강우유출수 처리사례는 드문 실정이다. 본 연구에서는 변형된 hydrocyclone과 perlite 여재를 조합한 hydrocyclone filter (HCF)을 이용하여 강우유출수내 미세입자의 제거능을 분석하였다. 입자물질들은 인공입자들을 이용하여 강우유출수내 입자농도를 모의 실험하였다. 인공입자들을 물에 분산시켜 강우유출수를 재현하였는데 사용한 입자들은 이온교환 수지, 도로측구 퇴적물질, 상업지역 맨홀퇴적물질, 그리고 실리카겔 등이다. 하부배출부와 vortex finder 구조를 달리하여 HCFopen system과 HCF-closed system으로 구분하여 처리능을 분석하였다. HCF장치는 아크릴 수지를 이용하였는데 hydrocyclone의 직경은 120 mm이고 여과조의 직경은 250 mm이고 전체적인 높이는 800 mm로 제작하였다. 운전조건별 유입수 농도와 입경을 다양하게 적용하였고 SS와 COD농도를 분석하여 처리효율을 산정하였다. HCF-open system의 경우 운전 가능한 최대 수면적부하율은 700 $m^3/m^2$/day이었고 HCF-closed system의 경우 수면적부하율 1,200 $m^3/m^2$/day까지이다. HCF-open system 운전결과 HCFclosed system에 비교하여 평균 수면적부하율은 2배 이상 높게 운전이 가능하며 처리효율도 8~20% 이상 향상되는 것으로 분석되었다. 또한 유입수 SS농도가 높을수록 처리효율이 증가하며, 입경이 클수록 수면적부하율의 변화에 대한 처리효율의 영향이 적은 것으로 분석되었다. HCF-closed system의 실험을 통한 수면적부하율 변화에 대한 실리카겔입자의 제거 효율과 CFD입자추적기법을 이용한 예측 처리효율을 비교한 결과 CFD에 예측효율이 실제실험결과와 비교하여 다소 높게 나타나지만 처리효율의 경향은 매우 유사하게 나타나 CFD추적기법을 이용한 HDS유형 처리장치 설계 시 유용한 도구로 활용될 수 있을 것으로 판단된다.

• 농촌계획
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• 제23권3호
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• pp.163-174
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• 2017

This study developed the prototype of the system and implemented its main functions, which is the intelligent integrated agricultural water management information system and service (IaWAMISS). The developed system was designed to be able to collect, process and analyze the agricultural water information of spatially dispersed reservoirs in whole country and spatial geographic information distributed in various systems of other organizations. The system, IaWAMISS, is also possible to provide the reproduced information services in each reservoir and space units, such as agricultural water demand and supply analysis and drought prediction, to the people, experts, and policy makers. This study defined the 6 step modules to develop the system, which are to design the components of intelligent integrated information system, to derive the utilization contents of existing systems, to design the new development elements for IaWAMISS, to design the reservoir information system can be used by managers of city and county, to designate the monitoring reservoirs managed by city and county, and finally to prepare the sharing system between organizations with the existing information systems. In order to implement the prototype of the system, this study shows the results for three important functions of the system: spatial integration of reservoirs' information, data link integration between the existing systems, and intelligent analysis program development to assist decision support for agricultural water management. For the spatial integration with the reservoir water information of the Korea Rural Community Corporation, this study get IaWAMISS to receive the real-time reservoir storage information from the measurement facility installed in the municipal management reservoir. The data link integration connecting databases of the existing systems, was implemented by integrating the meteorological information of the Korea Meteorological Administration with IaWAMISS, so that the rainfall forecast data could be derived and used. For the implementation of the intelligent analysis program, this study also showed the results of analysis and prediction of agricultural water demand and supply amount, estimation of Palmer drought index, analysis of flood risk area in typhoon course region, and analysis of the storage status of reservoirs related to each storm. This study confirmed the possibility and efficiency of an useful system development through the prototype design and implementation of IaWAMISS. By solving the preliminary 6 step modules presented in this study, it is possible not only to efficiently manage water by spatial unit, but also to provide the service of information and to enhance the relevant policy and national understanding to the people.

• 상하수도학회지
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• 제23권6호
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• pp.719-726
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• 2009

One of the alternative runoff management measures is on-site runoff mitigation, such as rainwater retention tank and infiltration facilities especially the latter that is possible to manage simultaneously runoff quality and quantity as a perspective of water-cycle. This study was conducted to develop a particle separator, inclined-pipe settling system, that could improve particle removal efficiency of road runoff as a pre-treatment device of stormwater infiltration. Solid particles larger than $100{\mu}m$ are separated by simple sedimentation; however, the significant amount of pollutants with a diameter less than $100{\mu}m$ remain in suspension. Without any treatment in that case of the runoff into infiltrate, groundwater would be deteriorated and also infiltration rate would be decreased by clogging. Therefore, we suggest optimal design parameters (inclined angle, pipe length, and surface loading rate) of inclined-pipe settling system which can be designed to effectively remove particles diameter smaller then $70{\mu}m$. Thus, the results showed TSS removal efficiency more than 80% with a particle diameter between $20{\mu}m$ and $70{\mu}m$, 100% above particle diameter $70{\mu}m$ for the inflow rate $0.018 m^3/m^2{\cdot}hr$ with pipe inclined at angle $15^{\circ}$.

• 한국방재학회 논문집
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• 제8권6호
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• pp.93-100
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• 2008

부산은 해안과 접해 있는 지형적 특성과 인구집중에 따른 과밀, 고층건축물의 신축, 높은 건축밀도에 따라 자연재난(태풍, 해일, 홍수, 폭풍 지진 등) 인적재난(화재, 붕괴, 폭발 교통사고 등)의 발생규모 및 피해 정도가 날로 증가하고 있다. 이를 해결하기 위하여 부산시에는 2007년 부산 Ubiquitous-Safety Busan 모델 전략 및 설계를 통해 2020년을 목표로 Ubiquitous-Safety 실현하여 시민들의 재산과 생명을 보호할 수 있는 안전 시스템을 구축하기 위한 기본계획을 수립하였다. 이에 본 연구에서는 부산지역의 Ubiquitous-Safety 실현을 통해 지역 경제에 미치는 파급효과를 정량적으로 분석하였다. Ubiquitous-Safety 실현에 따른 부산지역의 생산유발파급효과는 약 2,500억의 직 간접효과가 발생할 것으로 예측되었다. 또한 부가가치유발효과 는 약 1,155억원의 직 간접효과가 발생한 것으로 예측되었고, 고용유발효과는 약 5,580명의 직럭 Ａc 고용 파급효과가 창출될 것으로 예측되었으며 소득유발효과는 약 518억의 직 간접적인 부가가치 파급효과가 발생한 것으로 예측되었다. 부산 Ubiquitous-Safety 실현에 따른 지역경제 파급 분석에 관한 연구이다.

• 한국지리정보학회지
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• 제9권1호
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• pp.78-88
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• 2006

본 연구에서는 GIS기법을 활용한 산악지역의 돌발홍수 기준우량을 산정하기위해 지형기후학적 순간단위유량도(geomorphoclimatic instantaneous unit hydrograph, GCIUH)와 연계하여 유출해석을 수행하였다. 천동계곡 유역의 평균경사, 면적, 유로특성등 지형자료 구축에 GIS기법을 적용하였으며, 특히 GCIUH의 중요 입력변수인 하천차수 결정시 GIS기법을 활용하여 차수를 선정하였다. 산악지역 유출량 산정의 적합성을 위해 천동계곡 유역($14.58km^2$)에 대한 확률강우량으로 GCIUH의 첨두유량과 기본 보고서의 확률홍수량 자료를 비교하여 적합성을 확인하였다. 적합성이 확인된 GCIUH를 이용하여 천동계곡 유역의 돌발홍수 기준우량을 산정한 결과 한계유출량이 $11.42m^3/sec$일때, 최초 20분간 기준우량이 12.57mm가 발생하면 위험한 것으로 분석되었다.

• 한국환경복원기술학회지
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• 제3권2호
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• pp.53-65
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• 2000

The objectives of this study are to develop a stormwater management system that would contribute to improving water circulation, recycling storm water and promoting biodiversity in urban areas, to apply the system in an actual site, and to verify its effectiveness in order to generate a stormwater management system applicable in Korea. This study reviewed former researches and case studies, categorized stormwater management system into pre-treatment, retention and infiltration phases, and analyzed the strength and weakness of the techniques by synthesizing unit techniques of each stage. As a result, the process of the stormwater management system includes the following phases: 1) a rubble filtration layer; 2) a retention pond; 3) a infiltration pond; and 4) a stormwater retention pool (recirculation and recycling). Then, an empirical study to design and create the generated system according to the features of a site and to verify its effectiveness was conducted. The future study direction is to verify the effectiveness of the developed stormwater retention and infiltration ponds. To this end, it is planned to perform hydrological monitoring using automatic measuring equipment and monitoring on habitat bases and the biota living on the base. Based on its outcome, the applied model would be refined and improved to develop an alternative stormwater management system that would allow to achieve the improvement of urban water circulation, increase of biodiversity and efficient use of water resources.

• 상하수도학회지
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• 제22권1호
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• pp.65-71
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• 2008

급속 혼화공정에서 응집제의 동력학적 수화반응 특성을 고려하여 1초 이내의 순간혼합을 제시하고 있으며, 이러한 이론에 근거하여 설치된 Pump Diffusion Mixer(PDM)의 관내 응집제 확산 분포특성을 조사하였다. D=1,200mm 관경에서 압력수 유량비에 따라 응집제 주입지점으로부터 4.5D되는 지점에서 관 단면의 지점별 제타 전위를 측정하여 평가한 결과, 압력수의 유량비가 2%에서는 분사속도가 낮아 관 단면에 응집제가 골고루 분사되지 못하는 것으로 조사되었다. 그러나 압력수 유량비가 4% 이상이 되면 비교적 균등하게 혼합되며, 8%에서는 관 단면 전체에 균등하게 확산 분포되는 것으로 나타났다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1199-1203
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• 2005

Combined sewer overflows(CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available(which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a contiunous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban dranage system used analytical Probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics or the subject area using analytical Probabilistic model. Runoff characteristics manifasted the unique characteristics of the subject area with the infiltration capacity of soil and recovery of depression storage and was examined appropriately by sensitivity analysis. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range 3xDWF(dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a dicision of storage volume for CSOs reduction and water quality protection.

• Wind and Structures
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• 제26권6호
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• pp.369-382
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• 2018

Tornadoes are vertical swirling air formed because of the existence of layers of air with contrasting features of temperature, wind flow, moisture, and density. Tornadoes induce completely different wind forces than a straight-line (SL) wind. A suitably designed building for an SL wind may fail when exposed to a tornado-wind of the same wind speed. It is necessary to design buildings that are more resistant to tornadoes. In tornado-damaged areas, dome buildings seem to have less damage. As a dome structure is naturally wind resistant, domes have been used in back yards, as single family homes, as in-law quarters, man caves, game rooms, storm shelters, etc. However, little attention has been paid to the tornadic wind interactions with dome buildings. In this work, the tornado forces on a dome are computed using Computational Fluid Dynamics (CFD) for tornadic and SL wind. Then, the interaction of a tornado with a dome and a prism building are compared and analyzed. This work describes the results of the tornado wind effect on dome and prism buildings. The conclusions drawn from this study are illustrated in visualizations. The tornado force coefficients on a dome building are larger than SL wind forces, about 120% more in x- and y-directions and 280% more in z-direction. The tornado maximum pressure coefficients are also higher than SL wind by 150%. The tornado force coefficients on the prism are larger than the forces on the dome, about 100% more in x- and y-directions, and about 180% more in z-direction. The tornado maximum pressure coefficients on prism also are greater those on dome by 150% more. Hence, a dome building has less tornadic load than a prism because of its aerodynamic shape.

• Ocean Systems Engineering
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• 제6권3호
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• pp.265-287
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• 2016

The change of the global performance of a turret-moored FPSO (Floating Production Storage Offloading) with DP (Dynamic Positioning) control is simulated, analyzed, and compared for two different internal turret location cases; bow and midship. Both collinear and non-collinear 100-yr GOM (Gulf of Mexico) storm environments and three cases (mooring-only, with DP position control, with DP position+heading control) are considered. The horizontal trajectory, 6DOF (degree of freedom) motions, fairlead mooring and riser tension, and fuel consumptions are compared. The PID (Proportional-Integral-Derivative) controller based on LQR (linear quadratic regulator) theory and the thrust-allocation algorithm which is based on the penalty optimization theory are implemented in the fully-coupled time-domain hull-mooring-riser-DP simulation program. Both in collinear and non-collinear 100-yr WWC (wind-wave-current) environments, the advantage of mid-ship turret is demonstrated by the significant reduction in heave at the turret location due to the minimal coupling with pitch mode, which is beneficial to mooring and riser design. However, in the non-collinear WWC environment, the mid-turret case exhibits unfavorable weathervaning characteristics, which can be reduced by employing DP position and heading controls as demonstrated in the present case studies. The present study also reveals the plausible cause of the failure of mid-turret Gryphon Alpha FPSO in milder environment than its survival condition.