• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
• /
• pp.728-733
• /
• 2002

The measurement of river discharge is among the most fundamental observations and is necessary for understanding many water-related issues, such as flooding hazards, sediment transportation, and nutrient movement. Traditionally river discharge is estimated by measuring the water stage and converting the measurement to discharge using a stage-discharge rating curve. The possibility of monitoring river discharge from satellites has been largely ignored, because it is difficult to measure water surface information from space with sufficient precision. In this paper, an efficient approach to discharge estimation using mainly satellite data is developed and described. The proposed method, which focuses on the measurement of water-surface width coupled with river width-stage and stage-discharge relationships, is applied to the Yangtze River with good results.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.1964-1968
• /
• 2007

The river water heat source heat pump has the advantage in the performance compared to air source heat pump. Although its better performance, the large temperature difference between load and source makes system performance worse by nature. In this study, 2-stage compression is considered as the solution of this problem. Generally, heat pump is designed for maximum capacity rate, but it actually operates at part load condition in many cases. Therefore, an information on the part-load character is very important in view of the system overall performance. In this study, part-load performance tests of a R134a 2-stage compression heat pump were carried out over the river water and supply heating water temperature changes. The experimental results show that the system performance is influenced by the part load rates, river water temperature, load temperature, etc.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2009년도 하계학술발표대회 논문집
• /
• pp.1424-1428
• /
• 2009

The performance of a heat pump using river water as a heat source was compared with that of a conventional air-conditioner for cooling and a boiler system for heating. The heat pump system using river water considered the 1-stage cycle for cooling and the 2-stage cycle for heating. The COPs of the river water source heat pump were $0.5{\sim}1.1$ higher than those of the conventional system in the cooling season. The LCC of the river water source heat pump system was lower 13.5% and 32.4% than that of the conventional system I and II. In addition, when the initial cost ratios of the river water source heat pump system to the conventional system I and II were less than 1.2 and 1.4, respectively, an acceptable payback was found to be less than 5 years.

• 한국지열·수열에너지학회논문집
• /
• 제5권1호
• /
• pp.13-17
• /
• 2009

The river water heat source heat pump has the advantage in the performance compared to air source heat pump. In this study, an experimental study on a 2-stage heat pump, which is designed to utilize a river water heat source, were carried out. Generally, a heat pump is designed for maximum capacity rate, but it actually operates at part load condition in most cases. Therefore, an information on the part-load characteristic is very important in view of the system overall performance. In this study, part-load performance tests of a R134a 2-stage compression heat pump were carried out over the river water and supply heating water temperature changes.

• 설비공학논문집
• /
• 제17권11호
• /
• pp.1005-1013
• /
• 2005

The use of river water as a heat source of a heat pump has the advantage in the performance compared to the use of atmospheric air because the temperature variation of river water over the year is relatively small. In this study, the performance of the heat pump system using river water as a heat source was numerically investigated. A simulation model for the 2-stage compression heat pump system was developed with each component model composed of compressors, heat exchangers, a flash tank and electronic expansion devices. The peformance of the heat pump system using river water was improved by $50\%$ compared to that using atmospheric air in winter conditions.

• 한국수자원학회논문집
• /
• 제42권10호
• /
• pp.867-876
• /
• 2009

본 연구에서는 하상이 경년별로 변화함에 따라 발생되는 수위-유량 관계곡선의 오차를 보완하기 위해 최근(2006 년)의 수위-유량 관계곡선을 기준으로 채택하여 일원화시키고, 과거의 하상상태와 경년별로 작성되어 왔던 수위-유량 관계곡선들과의 관계 및 수위, 단면적, 유속 등에 대한 수리기하학적 특성을 분석하였다. 연구 대상지점으로는 낙동강의 주요지점인 적포교와 진동 지점을 택하였으며, 과거의 실측 유량값을 최근(2006년)하에서의 유량으로 환산하였을 때 얻어지는 수위(환산수위)와 과거수위와의 관계 및 환산유속과 과거유속간의 관계 그리고 수위-통수단면적 관계, 수위-유속 관계 등의 상관식을 도출하여 기왕의 많은 자료들을 활용할 수 있도록 상관해석을 실시하였다.

• 한국항만학회지
• /
• 제12권1호
• /
• pp.131-143
• /
• 1998

This paper presents derivation of stage-discharge curve for Yangsan river. To derivate of stage-discharge lationship is one of the essential research areas in the water resource field. It provides reliable data a long term planning and hydrologic quantity on water resource development by quantitative analysis. The rating curve derivated through 15 discharge-observation on Yangsan river basin in 1997 has been estimated Q=1283.0262-1553.3158H+477.2702H2. According to the rating curve, the highest water level 2.6m, the limited water-level should be bound to the maximum of 2.6m. Before this research, stage-discharge curve of Yangsan river has not been developed, and only 15 discharge observation(hydrometry) has been carried out though this research. Therefore it seems necessary to collect observation data through a long term process to obtain a reliable rating curve equation.

• 한국항만학회지
• /
• 제14권1호
• /
• pp.107-114
• /
• 2000

Derivation of stage-discharge relationship and characteristics for Yangsan river is presented in this paper. This research has been conducted as the second one after the first trial in 1997. The determination of discharge at a Yangsan river gauging was best made by measuring the flow velocities with a current meter and rod float. The rating curve obtained through 52 stage-discharge measurements on Yangsan river basin in 1999 is represented by Q=15.3540-140.6076H+182.44372H$^2$, which is discovered to be most excellent among other curves in reliability analysis. The observed stage-discharge data for Yangsan river was tested by HEC-RAS program, and reproduction of discharge by the induced curve was investigated and compared with the computational results. The rating curve of Yangsan river shows characteristics of Yangsan river more accurately compared with those separated in terms of water levels.

• 한국수자원학회논문집
• /
• 제33권5호
• /
• pp.635-645
• /
• 2000

감조하천에서는 수위, 유량과 조석이 상호관련이 있다. 특히 저수위에서 조석의 영향을 감안하지 않은 수위-유량관계는 부정확하다. 본 논문에서는 수위와 조위의 수면차를 변수로 하여 감조하천에서의 유량을 계산할 수 있도록 하였다. 이를 위해 태화강 감조부에 위치한 울산수위관측소 지점의 저수위 유량을 수위 및 수위와 조위의 수면차로 나타내는 다중회귀식을 개발하였으며, 기존의 수위-유량곡선식과 비교한 결과 우수한 적용성을 확인하였다.

• 대한임베디드공학회논문지
• /
• 제18권3호
• /
• pp.133-139
• /
• 2023

This paper proposes a two-stage Water Shield Automation System (WSAS) to predict the possibility of river overflow and vehicle flooding due to sudden rainfall. The WSAS uses a two-stage Deep Neural Network (DNN) model. First, a river overflow prediction module is designed with LSTM to decide whether the river is flooded by predicting the river's water level rise. Second, a vehicle flooding prediction module predicts flooding of underground parking lots by detecting flooded tires with YOLOv5 from CCTV images. Finally, the WSAS automatically installs the water barrier whenever the river overflow and vehicle flooding events happen in the underground parking lots. The only constraint to implementing is that collecting training data for flooded vehicle tires is challenging. This paper exploits the Image C&S data augmentation technique to synthesize flooded tire images. Experimental results validate the superiority of WSAS by showing that the river overflow prediction module can reduce RMSE by three times compared with the previous method, and the vehicle flooding detection module can increase mAP by 20% compared with the naive detection method, respectively.