비정형 데이터를 활용한 가뭄평가 - 보령지역을 중심으로 -

정진홍,박동혁,안재현,Jung, Jinhong,Park, Dong-Hyeok,Ahn, Jaehyun 한국수자원학회 2020 한국수자원학회논문집 Vol.53 No.12

Drought is caused by a combination of various hydrological or meteorological factor, so it is difficult to accurately assess drought event, but various drought indices have been developed to interpret them quantitatively. However, the drought indexes currently being used are calculated from the lack of a single variable, which is a problem that does not accurately determine the drought event caused by complex causes. Shortage of a single variable may not be a drought, but it is judged to be a drought. On the other hand, research on developing indices using unstructured data, which is widely used in big data analysis, is being carried out in other fields and proven to be superior. Therefore, in this study, we intend to calculate the drought index by combining unstructured data (news data) with weather and hydrologic information (rainfall and dam inflow) that are being used for the existing drought index, and to evaluate the utilization of drought interpretation through verification of the calculated drought index. The Clayton Copula function was used to calculate the joint drought index, and the parameter estimation was used by the calibration method. The analysis showed that the drought index, which combines unstructured data, properly expresses the drought period compared to the existing drought index (SPI, SDI). In addition, ROC scores were calculated higher than existing drought indices, making them more useful in drought interpretation. The joint drought index calculated in this study is considered highly useful in that it complements the analytical limits of the existing single variable drought index and provides excellent utilization of the drought index using unstructured data.

플럭크기를 이용한 응집공정 진단에 관한 연구

정진홍(Jung, Jinhong),최계운(Choi, Gye-Woon),박재로(Park, Jae-Roh) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.12

정수처리공정 중 응집공정의 효율을 평가하기 위하여 Floc Size 분포를 분석하여 응집공정의 효율 평가를 수행하였 다. 응집 효율은 탁도를 기준으로 평가하는 방법보다 응집 상태를 직접 평가하는 Floc의 크기 및 개수를 분석하여 정량화하는 기법을 제시하였다. 원수의 탁도 분포에 따른 Floc의 성장 상태를 분석하였다. 응집지에서 원수 탁도가 5.0 NTU 내외로 유입되었을 경우 응집지 각 단의 G값이 각각 50 sec-1,, 30 sec-1, 10 sec-1일 때 효율이 가장 높게 나타났으며, 원수 탁도가 263 NTU로 유입되었을 경우 G값을 각각 65 sec-1, 40 sec-1, 10 sec-1으로 운전한 경우 효율이 가장 높게 나타났으며, 이 때 1200㎛ 이상의 Floc 개수는 약 14개로 분석되었다. G값에 따라 응집효율을 평가할 수 있는 지표인자로 Floc의 크기 및 개수로 공정 진단 수행이 가능할 것으로 판단된다. An assessment of flocculation was performed by measuring the distribution of the floc size during sedimentation in water works. The size and number of flocs have a greater effect on an evaluation of the efficiency of flocculation rather than the turbidity. The data was collected in situ using particle image velocimetry and image analysis. The measurements were carried out at a water depth of 1m. The removal efficiency of the total organic compounds, UV absorbance and turbidity depended on the size and floc size distribution in flocculation as the G value. The G value of 50 sec-1, 30 sec-1 and 10 sec-1 showed the highest degree of efficiency in the case of an inlet water turbidity of 5 NTU, and the highest degree of efficiency was observed at a G value of 65 sec-1, 40 sec-1 and 10 sec-1 when the inlet water turbidity was 263 NTU. The number of flocs with a distribution of above 1,200㎛ was 14. The dynamics between two important growth mechanisms were investigated as the energy input changed. This is a certain method that makes use of the size and number of flocs as an efficiency assessment.

공동주거단지 유출 잡배수의 전처리를 위한 침전부상공정 적용 연구

정진홍 ( Jinhong Jung ),박나리 ( Nari Park ),장향연 ( Hyangyoun Chang ),임현만 ( Hyunman Lim ),김원재 ( Weonjae Kim ) 한국물환경학회 2021 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2021 No.-

다중홉 통신 기법을 활용한 네트워크 로봇의 협력적 경로 탐색

정진홍(Jinhong Jung),김성륜(Seong-Lyun Kim) 한국통신학회 2008 韓國通信學會論文誌 Vol.33 No.11B

본 논문에서는 다중 로봇 (multi-robot)을 활용한 응용분야 중, 미지의 영역에 대한 탐색 (exploration) 능력을 향상시켜서, 주어진 미로 (maze)에서 다중 로봇이 통신을 통해서 협력적으로 출구를 찾아가는 효율적인 방안을 제안하였다. 즉, 미로 형태의 임의의 환경을 생성한 후, 로봇을 무작위로 배치시켜 상호간에 통신을 통하여 출구로 신속히 모두 빠져나오는 문제를 다루고 있다. 미로탐색을 위해 다중 로봇의 지역 탐색에서 사용되었던, 프론티어 셀, 셀 유틸리티등 기존 연구를 활용하였다. 또한 로봇간의 다중홉 무선 통신 (multihop wireless communications)을 위해서 이동성 (mobility)에 강한 일종의 홉기반 (hop-by-hop) 라우팅인, 랜덤 베스킷 볼 라우팅을 채용하였다. 또한, 출구를 찾은 로봇이 일정한 확률에 의거하여 출구 앞에서 정지하거나 혹은, 빠져나가는 의사 결정을 하여, 이 확률적인 결정이 다른 로봇의 행동에 어떻게 영향을 주는지를 실험적으로 조사하였다. 즉, 출구를 찾은 로봇이 현재 위치에서 멈추어서, 통신 중계 지점 (relay)으로 어떻게 활동되어야 최적인지에 대한 문제를 모의 실험을 통해 파악해보았다. This paper presents an algorithm for the path-finding problem in unknown environments with cooperative and commutative multi-robots. To verify the algorithm, we investigate the problem of escaping through the exit of a randomly generated maze by muti-robots. For the purpose, we adopt the so called frontier cells and cell utility functions, which were used in the exploration problem for the multi-robots. For the wireless communications among the mobile robots, we modify and utilize the so called the random basket routing, a kind of hop-by-hop opportunistic routing. A mobile robot, once it finds the exit, will choose its next action, either escape immediately or stay-and-relay the exit information for the others, where the robot takes one action based on a given probability. We investigate the optimal probability that minimizes the average escaping time (out of the maze to the exit) of a mobile robot.

공동주거단지에서의 잡배수 유출특성에 관한 연구

정진홍 ( Jinhong Jung ),박나리 ( Nari Park ),장향연 ( Hyangyoun Chang ),안광호 ( Kwanho Ahn ),김원재 ( Weonjae Kim ) 한국물환경학회 2021 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2021 No.-

도시 용수 통합관리 방안 연구

정진홍(Jung, Jinhong),최계운(Choi, Gye-Woon),오현제(Oh, Hyunje) 한국산학기술학회 2013 한국산학기술학회논문지 Vol.14 No.12

인구 증가와 함께 도시개발로 인한 지구온난화의 심각, 대기질 악화, 수질 오염 및 수생태계 파괴 등 도시환 경 문제가 심화되고 있다. 또한 도시 개발 시 토지 피복면적 변화에 따른 불투수층 면적이 증가되는 인공적 요인과 이상기후에 의해 강우특성이 변화하는 자연적 요인으로 도시 열섬현황 심화, 용수 부족, 지하수위 저하, 침수 피해 등 을 야기하여 물순환 건전성을 저해시키고 있다. 이를 해결하기 위해서는 체계적인 정보기술 인프라 및 환경센서 기술 을 활용하여 도시 물순환 건전성을 제고시키기 위한 물순환시스템 구축기술 개발이 필요하다. 본 연구에서는 도시 내 에서 물순환 건전성을 평가하는 방법으로 자연계 물순환 건전화율 및 인공계 물순환 건전화율 평가식을 제시하여, 도 시화 및 산업화로 인해 발생하는 물순환 왜곡 정도를 정량적으로 분석하고, 도시 개발 후 물순환 건전성을 확보하기 위한 방법론을 제시하였다. This study aims at suggesting a evaluation method of water cycle soundness in U-City. The distortion of water cycle soundness induced industrialization and urbanization was quantitatively analyzed. In order to evaluate the soundness of water cycle in U-City the reduction ratio of runoff was evaluated in comparison of before the construction of the water recycling facilities for natural water cycle, the reduction ratio of urban water was evaluated in comparison of before the introduction of the artificial recycling facilities for artificial water cycle.

간세포암종에서의 체부정위방사선치료

정진홍 ( Jinhong Jung ),윤상민 ( Sang Min Yoon ) 대한간암학회 2018 대한간암학회지 Vol.18 No.2

With recent remarkable technological advances in radiation therapy, stereotactic body radiation therapy (SBRT) is regarded as an alternative treatment option for hepatocellular carcinoma (HCC) that is not suitable for curative treatment. Several prospective and retrospective studies on the use of SBRT in patients with HCC showed promising results. Furthermore, on-going prospective studies are examining the role of SBRT as a single ablative modality or a combination treatment in patients with HCC. Here, we summarize previous studies and recent updates and discuss the future perspectives of SBRT for HCC. (J Liver Cancer 2018;18:94-102)

하수처리시설에서 인 고도처리를 위한 일체형 침전부상공정(SeDAF)의 응집제 주입농도 자동제어기법 검토

장여주,정진홍,김원재,Jang, Yeoju,Jung, Jinhong,Kim, Weonjae 대한상하수도학회 2020 상하수도학회지 Vol.34 No.6

To remove phosphorus from the effluent of public wastewater treatment facilities, hundreds of enhanced phosphorus treatment processes have been introduced nationwide. However, these processes have a few problems including excessive maintenance cost and sludge production caused by inappropriate coagulant injection. Therefore, the optimal decision of coagulant dosage and automatic control of coagulant injection are essential. To overcome the drawbacks of conventional phosphorus removal processes, the integrated sedimentation and dissolved air flotation(SeDAF) process has been developed and a demonstration plant(capacity: 100 ㎥/d) has also been installed. In this study, various jar-tests(sedimentation and / or sedimentation·flotation) and multiple regression analyses have been performed. Particularly, we have highlighted the decision-making algorithms of optimal coagulant dosage to improve the applicability of the SeDAF process. As a result, the sedimentation jar-test could be a simple and reliable method for the decision of appropriate coagulant dosage in field condition of the SeDAF process. And, we have found that the SeDAF process can save 30 - 40% of coagulant dosage compared with conventional sedimentation processes to achieve total phosphorus (T-P) concentration below 0.2 mg/L of treated water, and it can also reduce same portion of sludge production.

인 고도처리를 위한 일체형 침전부상공정(SeDAF)의 최적 응집제 주입조건 결정

장여주 ( Yeoju Jang ),정진홍 ( Jinhong Jung ),장향연 ( Hyangyoun Chang ),박나리 ( Nari Park ),임현만 ( Hyunman Lim ),김원재 ( Weonjae Kim ) 한국수처리학회(구 한국수처리기술연구회) 2020 한국수처리학회지 Vol.28 No.4

Algal blooms are caused by eutrophication, increased water temperature, and reduced water flow rate, and produce taste·odor compounds and health problems associated with cyanobacterial toxins. To prevent eutrophication and algal blooms, the Ministry of Environment (MOE) in Korea reinforced effluent standards for wastewater treatment facilities and, as a result, spurred the implementation of various advanced wastewater treatment processes to achieve compliance. Current tertiary wastewater treatment techniques are conventionally single processes, such as sedimentation or flotation, and have high operational costs and produce undesirable sludge problems due to excessive coagulant injection. Here, we develop a sedimentation and dissolved air flotation (SeDAF) process that integrates sedimentation and flotation for applications in advanced wastewater treatment. Jar-tests were used to evaluate water quality and treatment efficiency for sedimentation and sedimentation·flotation processes, respectively. Equations that estimate the optimal coagulant dosage are proposed to enhance the field applicability of the SeDAF process. Two types of jar-tests, both sedimentation and sedimentation·flotation, and multiple regression analyses are comprehensively examined to identify appropriate operation conditions for the SeDAF process considering fluctuations in field conditions such as T-P concentration, PO4-P / T-P ratio, turbidity, and flow rate etc.

능동 추천을 통한 추천 시스템 성능 향상

이민경(Minkyung Lee),정진홍(Jinhong Jung),강유(U Kang) 한국정보과학회 2016 한국정보과학회 학술발표논문집 Vol.2016 No.12