• Title/Summary/Keyword: Sihwa embankment

Search Result 6, Processing Time 0.018 seconds

Vegetation Change Detection in the Sihwa Embankment using Multi-Temporal Satellite Data (다중시기 위성영상을 이용한 시화 방조제 내만 식생변화탐지)

  • Jeong, Jong-Chul;Suh, Young-Sang;Kim, Sang-Wook
    • Journal of Environmental Science International
    • /
    • v.15 no.4
    • /
    • pp.373-378
    • /
    • 2006
  • The western coast of South Korea is famous for its large and broad tidal lands. Nevertheless, land reclamation, which has been conducted on a large scale, such as Sihwa embankment construction project has accelerated coastal environmental changes in the embankment inland. For monitoring of environmental change, vegetation change detecting of the embankment inland were carried out and field survey data compared with Landsat TM, ETM+, IKONOS, and EOC satellite remotely sensed data. In order to utilize multi-temporal remotely sensed images effectively, all data set with pixel size were analyzed by same geometric correction method. To detect the tidal land vegetation change, the spectral characteristics and spatial resolution of Landsat TM and ETM+ images were analyzed by SMA(spectral mixture analysis). We obtained the 78.96% classification accuracy and Kappa index 0.2376 using March 2000 Landsat data. The SMA(spectral mixture analysis) results were considered with comparing of vegetation seasonal change detection method.

Dynamic Characteristic Analysis of Water-Turbine Generator Control System of Sihwa Tidal Power Plant (시화조력발전소 수차발전기 제어시스템의 동적 특성 해석)

  • Ahn, Sang-Ji;Ban, Yu-Hyeon;Park, Chul-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.61 no.4
    • /
    • pp.180-185
    • /
    • 2012
  • Tidal power is one of new and renewable energy sources. The seawater is stored inside a tidal embankment built at the mouth of a river or bay, where tides ebb and flow. The water turbine-generators produce power by exploiting the gap in the water level between the water outside and inside the embankment. Tidal power plant is a large plant that is installed on the sea. And then, the facility's operations and a separate control system for monitoring and maintenance is required. However, this plant predictive control of building systems and technologies have been avoided the transfer of technology from advanced global companies. Accordingly, the control system for core technology development and localization is urgently needed. This paper presents modeling and simulation using by PSS/E about generator, governor, exciter, and power system stabilizer for control system in Sihwa tidal power plant to improve the efficiency and develope of core technology. And the dynamic characteristics of governor and exciter were analyzed.

Interpretation of Soft Ground Deformation under Embankment using the Electrical Resistivity Survey (전기비저항탐사를 이용한 성토하부 연약지반의 변형 해석)

  • Kim, Jae-Hong;Hong, Won-Pyo;Kim, Gyoo-Bum
    • The Journal of Engineering Geology
    • /
    • v.21 no.2
    • /
    • pp.117-124
    • /
    • 2011
  • Soil deformations such as settlement, heaving and lateral flow have frequently happened on marine reclaimed soft grounds due to embankment filling or banking. The electrical resistivity survey was applied to investigate on ground surface such soil deformation without disturbance of ground. A test embankment was performed to assess soil deformation in marine reclaimed soft grounds, where was located at Sihwa area in western coast of Korean peninsula. The soft ground was composed of clayey sediments. After embankment filling, the boundary of soil deformation affected by the filling could be investigated with application of the electrical resistivity survey. The result of electric resistivity survey shows that the extent of deformation is about 5 m laterally to the southern direction of embankment and about 5~6 m vertically in depth, which is about 1-1.2 times of embankment height. This shows that the electric resistivity survey can be applied to interpret the ground deformation in a soft ground region.

A Study on Start·Stop System at Water Turbine-Generator for Tidal Power Plant (조력발전용 수차발전기의 기동·정지시스템에 관한 연구)

  • Oh, Min-Hwan;Park, Chul-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.63 no.2
    • /
    • pp.113-118
    • /
    • 2014
  • Tidal power is one of new and renewable energy sources. Tidal power is generated by using the gap in the water level between the water outside and inside the embankment. All tidal power plant in Korea were being operated by import of turn-key from abroad. The know-how and technology which are the most important to build predictive control system has become increasingly difficult to obtain from advanced countries because most of them avoid to transfer, which the domestic development of the control system is needed. In this paper, a study on start stop system at water turbine-generator for tidal power plant at the beginning of development was presented. For improvement the efficiency and develope of core technology of the start stop system, the technique and characteristics of tidal power, modeling, maximum generation calculation method, and optimal control of joint control system in Sihwa tidal power plant were studied.

Effects of NaCl Concentration on the Growth of Native Willow Species Collected in a Coastal Reclaimed Land (간척지 자생 버드나무의 NaCl 농도별 생육반응)

  • Yeo, Jin-Kie;Park, Jung-Hyun;Koo, Yeong-Bon;Kim, Hyun-Chul;Shin, Han-Na
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.43 no.2
    • /
    • pp.124-131
    • /
    • 2010
  • This study was conducted to investigate the potentials for the forest restoration on reclaimed land by using willow trees (Salix koreensis Anderson) selected from a coastal reclaimed land made in inside of the Sihwa tide embankment. We first collected six individual willow trees that were the only tree species grown in the reclaimed land. Total 7 clones from cuttings of the collected trees and the control were grown in a greenhouse for two months prior to applying the different concentrations of NaCl solutions (0.0%, 0.1%, 0.5%, and 1.0%). One month after the NaCl application, the survival rates of clones from both the collected trees, and the control were significantly decreased in a NaCl dose-dependent manner. However, there was no significant difference between the collected trees and the control in terms of survival rate, hight and diameter of cuttings, and the numbers of leaves in greenhouse condition. In conclusion, the willow trees collected from the coastal reclaimed land showed no tolerance against NaCl compared to the control grown in ordinary soil, suggesting that further study is required to determine what the most important factor is to select salt tolerant tree species.