• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.272-277
• /
• 2005

Initial mixing characteristics in near field regions were analyzed by FLOW-3D, for analyzing mixing behavior of submerged discharge from freshwater lake in sea water. FLOW-3D model was applied to the region near Geum-ho dike for its verification. Simulation results from FLOW-3D were compared to the observed data for the verification periods. FLOW-3D showed resonable prediction results compared to the observed data, except underestimation in area near outfall. Particularly, FLOW-3D showed a good prediction for movement of buoyancy jets. In addition, FLOW-3D model was applied to the region near Saemangeum dike, which is to be constructed in near future. It was expected that the results of model application to Saemangeum area could provide substantial information in planning submerged discharge facilities. Based on the model applications to Saemangeum area, it was recommended that outfall should be located to the distance which gave an enough depth of outfall from water surface.

• Solar Energy
• /
• v.19 no.1
• /
• pp.47-57
• /
• 1999

A building and the solar are related to the privilege of solar benefit. To make step, it is required to build up an object, chase the position of object and the solar, find the shadow occurrence. On the subject of direct illuminance, an intensive emission of irradiation is proposed to directly project to the benefit area. Simultaneously on the indirect illuminance, the integration of a finite element incident to the benefit area can be multiplied by the hemisphere luminance. A caution should be paid to eliminate the occupation area of the object around on the hemispherical sky, which can help run more accurate prediction.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.1405-1410
• /
• 2006

Purpose of this research is that offers basic data for optimized design using neural network method to calculate consolidation settlement in study area. In this research, preformed the neural network method that analyzed the settlement characteristics of soft ground nearby study area. Thus, data base established on ground properties and consolidation settlement of neighboring area. In addition, designed the optimum neural network model for prediction of settlement through network learning and consolidation settlement prediction using consolidation settlement DB and ground properties DB. Optimized neural network model decided by repeated learning for various case of hidden layers. In this study, proposed that the optimized consolidation settlement calculation method using neural network and verified which is the optimized consolidation settlement calculation method using neural network.

• Journal of the Korean Society of Safety
• /
• v.12 no.2
• /
• pp.57-64
• /
• 1997

Fatigue crack propagation behaviors and life prediction for SUS 321 plate and its electron beam weld metal were investigated using compact tension specimens. The larger the stress ratio is, the faster the crack propagates, but the variation of crack propagation rate decreases. The effect of stress ratio is greater in the slow crack propagation area than in the faster one. The crack propagation rate of electron beam weld metal is faster than that of base metal because of hardening, weld defect and residual stress in welding area. The crack propagation rate of transverse weld metal has a lower than that of base metal due to the effect of residual stress, but in the time of passing through welding area, has a higher rate. The crack propagation rate using $\Delta$K$_{eff}$ can be well plotted regardless of stress ratio. The fatigue life prediction method of considering crack closure more exactly predicts fatigue life than conventional one. conventional one.e.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.38 no.6
• /
• pp.106-112
• /
• 2001

Unfortunately, the area without economical efficiency, especially the far distance sea, is much lower than that of a urban area-built-up area. It should be promoted the equivalent level to a urban area in the light of future-oriented universal service. Actually, Because propagation environment of mobile communication in the sea is greatly different from that for inland focused on built-up area, a propagation prediction model in the sea should be distinguished from inland-based one. Accordingly, the purpose of this study is to suggest the propagation prediction model for the sea service as a method to minimize unnecessary facilities investment and maintenance caused by additional or new building of a base station. If mobile phone service for far distance sea is provided by expanding limited communication zone of narrow band CDMA mobile communication whose spread band FA is 1.2288MHz. Suggested propagation prediction model includes five parameters to minimize facilities investment of a base station and maximize channel capacity: equivalent line of sight, chip delay by PN code, antenna altitude, power of base station and gain of antennas. Finally, suggested propagation prediction model is simulated and, the results are examined for its utility by comparing with loss of free space.

• Journal of the Korean Institute of Gas
• /
• v.22 no.2
• /
• pp.29-33
• /
• 2018

Accident likelihood is growing due to a correlation for gas and electricity installed in the area of dense energy consumption like traditional market and underground shopping center. In order to prevent and respond accident risks related to gas and electricity in this area, it should be monitored and predicted for factors of gas leak or electricity by developing safety management system. This study is about accident prediction model development considering fire risk factor related to gas accident. The temperature variation characteristic near a gas burner was analyzed. Also, accident prediction algorithm and related module were developed to prevent fire in the area of dense energy consumption.

• Tunnel and Underground Space
• /
• v.23 no.1
• /
• pp.31-41
• /
• 2013

Graphical method has been widely applied to the prediction of subsidence area, and is known to have advantages in analysis of trough subsidence which is common in horizontally seamed mine area. However, it is reported that most of the ore bodies in Korea are geologically inclined from sub-horizontal to steep, and therefore, the sinkhole subsidence is frequent in abandoned mine area. For these reasons, it is not to be desired that graphical method is applied for predicting the subsidence occurrence. This paper describes the results of subsidence zone prediction considering the dip direction and the opposite direction of inclined ore bodies from the case studies on the 163 subsidence occurrence regions. The results show also the assumed angle which can define the range of subsidence in the surface area. In conclusion, the limit of this angle is suggested after taking into account the comparison with graphical method and the application to the case histories.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.35 no.2
• /
• pp.113-122
• /
• 2017

Natural disasters caused by climate change are increasing globally. There are few studies on the quantitative analysis methods for predicting damages in the island area due to sea level rise. Therefore, it is necessary to study the damage prediction analysis method using the GIS which can quantitatively analyze. In this paper, we analyze the cause and status of sea level rise, quantify the vulnerability index, establish an integrated terrestrial modeling method of the ocean and land, and establish a method of analyzing the damage area and damage scale due to sea level rise using GIS and the method of making the damage prediction figure was studied. In order to extract the other affected areas to sea level rise are apart of the terrain model is generated by one requires a terrain modeling of target areas are offshore and vertical reference system differences in land, found the need for correction by a tidal observations and geoid model there was. Grading of terrain, coastline erosion rate, coastal slope, sea level rise rate, and even average by vulnerable factors due to sea level rise indicates that quantitative damage prediction is possible due to sea level rise in the island area. In the case of vulnerable areas extracted by GIS, residential areas and living areas are concentrated on the coastal area due to the nature of the book area, and field survey shows that coastal changes and erosion are caused by sea level rise or tsunami.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.50 no.3
• /
• pp.215-222
• /
• 2022

The purpose of air traffic flow management is to balance demand and capacity in the national airspace, and its performance relies on an accurate capacity prediction of the airport or airspace. This paper developed a regression model that predicts the number of aircraft actually departing and arriving in a terminal maneuvering area. The regression model is based on a boosting ensemble learning algorithm that learns past aircraft operational data such as time, weather, scheduled demand, and unfulfilled demand at a specific airport in the terminal maneuvering area. The developed model was tested using historical departure and arrival flight data at Incheon International Airport, and the coefficient of determination is greater than 0.95. Also, the capacity of the terminal maneuvering area of interest is implicitly predicted by using the model.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.10
• /
• pp.41-48
• /
• 2010

In this study, grain size distribution of dredged soil and suspended solid distribution of supernatant in containment area were measured and compared with design prediction for suitability evaluation on prediction of suspended solid concentration of supernatant in conventional design of containment area. In addition to that, relationship were also analyzed between current velocity and suspended solid concentration of supernatant. Evaluation results show a relatively good agreement between field measurement and design prediction. On contrast, field measurement and design prediction show a quite different value each other in the early stage of dredging or at a point that current velocity increases. It is believed that this is due to that conventional design method of containment area does not account for ponding depth and current velocity which change sensitively with dredging period. Since current velocity and distribution of suspended solid concentration measured simultaneously show a similar trend, it is observed that there exists a close relationship between current velocity and distribution of suspended solid concentration. Therefore, a new design method for containment area, which can consider sedimentation of suspended solid that changes with interface height of dredged soil, ponding depth, current speed of supernatant, is necessary in order to predict the situation change of containment area more precisely.