• Earthquakes and Structures
• /
• v.12 no.6
• /
• pp.653-663
• /
• 2017

A seismic margin assessment evaluates how much margin exists for the system under beyond design basis earthquake events. Specifically, the seismic margin for the entire system is evaluated by utilizing a systems analysis based on the sub-system and component seismic fragility data. Each seismic fragility curve is obtained by using empirical, experimental, and/or numerical simulation data. The systems analysis is generally performed by employing a fault tree analysis. However, the current practice has clear limitations in that it cannot deal with the uncertainties of basic components and accommodate the newly observed data. Therefore, in this paper, we present a Bayesian-based seismic margin assessment that is conducted using seismic fragility data and fault tree analysis including Bayesian inference. This proposed approach is first applied to the pooltype nuclear research reactor system for the quantitative evaluation of the seismic margin. The results show that the applied approach can allow updating by considering the newly available data/information at any level of the fault tree, and can identify critical scenarios modified due to new information. Also, given the seismic hazard information, this approach is further extended to the real-time risk evaluation. Thus, the proposed approach can finally be expected to solve the fundamental restrictions of the current method.

• Journal of Korean Society for Geospatial Information Science
• /
• v.14 no.1 s.35
• /
• pp.75-83
• /
• 2006

Satellite imagery is generally used for investigating the damage from natural disaster for wide area and remotely piloted vehicle or aerial photos are used for the local damage. But for more detailed information such as damages of public facilities, these methods are inadequate and so in this case field surveying has been carried out. We tried to estimate the damage of public facilities faster and more accurately using photogrammetric method. We developed a digital stereo camera system by fixing two digital cameras on a frame, and with this system the photos of actually damaged areas were collected. The damages were estimated from these stereo photos. Then the estimated data was compared with field surveying data in order to verify our system.

• Journal of Korean Society for Geospatial Information Science
• /
• v.12 no.1 s.28
• /
• pp.21-29
• /
• 2004

Floods are disastrous natural phenomena which result in numerous losses of life and property. It is possible to minimize the potential risk by adopting a disaster management system. Nowadays, Geo-Spatial Information System(GSIS) and computer-modelling techniques have assisted scientists and engineers with determining flood disaster assessments, GIS technologies especially have the advantage of performing spatial analysis as well as generating the model for a flood hazard. Therefore, this paper presents the flood management system based on 3D GSIS that can cope with natural disasters actively and manage flood hazard systematically by constructing the database using hydrological data, digital map, DEM, and high-resolution satellite images.

• Journal of Korean Society for Quality Management
• /
• v.34 no.1
• /
• pp.40-47
• /
• 2006

Claim history data of rather long period were collected to assess reliability and warranty cost analyses. The data were appropriately organized to be used for further statistical analyses. For each critical component, nonparametric statistical method was applied to obtain reliability plot. Hazard plots of the components in a subsystem or system level were also obtained. Competing risk model was assumed to obtain the performance of the subsystem or system level.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.5A
• /
• pp.451-459
• /
• 2007

RFID it reads information which is it writes, the semiconductor chip for and the radio frequency system which uses the hazard antenna it has built-in transmission of information it talks. Formation which is transmitted like this collection and America which it filtrates wey the RFID search service back to inform the location of the server which has commodity information which relates with an object past record server. The hazard where measurement analysis result the leader for electronic interference does not occur consequently together from with verification test the power level which is received from the antenna grade where it stands must maintain minimum -55dBm and the electronic interference will not occur with the fact that, antenna and reel his recognition distance the maximum 7m until the recognition which is possible but smooth hazard it must stand and and with the fact that it will do from within and and and 3-4m it must be used Jig it is thought.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.10
• /
• pp.47-55
• /
• 1999

In this paper, a new function hazard elimination algorithm is proposed for asynchronous circuit synthesis. In previous approach, function hazard is eliminated by using state graph which is obtained from the state assignment on STG(signal transition graph) representing transition relationship among signals. These algorithms can use conventional hazard removal and synthesis method applied in synchronous system, but it has much computational complexity and takes much time to handle the state graph. Although some hazard elimination algorithm from STG were proposed, it could not reduce the area overhead due to the addition of new signals. The proposed algorithm eliminate function hazard directly on STG and also control the number of minterms and product-term of added signal in order to minimize the area overhead. Experimental results on benchmark data shows that overall circuit area after hazard elimination is decreased about 15% on the average than that of previous method.

• Journal of KIISE
• /
• v.43 no.6
• /
• pp.662-667
• /
• 2016

As electric and electronic control systems have sharply increased in vehicles, safety accident has emerged as an important issue. Therefore, in order to ensure safety of the vehicle, engineers are required to identify the hazards utilizing PHA and HAZOP, etc. in the early phase of development and implement safety mechanisms to prevent them. HAZOP has been widely used in a systematic manner based on guidewords. However, HAZOP identifies malfunctions from the top-level functionality provided by the system, so it cannot sufficiently identify hazards during the system operation. This leads to restrictions in designing testcases, because the safety requirements are derived from only some of the hazards. This research aimed to provide a hazard identification method utilizing Use case description, which defines operation procedure of the system and HAZOP and a testcase design method based on safety requirements. We introduced a case study on Smart Key Control System in vehicles and compared with hazards identification results based on HAZOP, to demonstrate the effectiveness of this study. The result of this study could potentially reduce development cost and increase system quality by adequately identifying hazards and safety requirements and designing the related testcase.

• KSCI Review
• /
• v.14 no.1
• /
• pp.231-239
• /
• 2006

Geographic information system (GIS) geography reference it talks the software system which is possible. When like this geographic information system in key feature trying to observe the problem which is an expression of geography information in the center, the research and development with 3 dimension expressions is active from 2 dimension expressions of existing and it is advanced. double meaning geography information which is huge to be quick, the place where it controls efficiently there is a many problem, the ring from the dissertation which it sees and 3 dimensions and efficient scene of the GIS rendering compared to the ring from hazard image base modeling and rendering compared to hazard proposal LDI (Layered Depth Images) it uses GIS rendering compared to the ring to sleep it does. It acquired the terrain data of 3 dimensions from thread side base method. terrain data of 3 dimensions which are acquired like this the place where it has depth information like this depth information in base and the LDI, it did it created. Also it was a traditional modeling method and 3DS-Max it used and it created the LDI. It used LDI information which is acquired like this and the GIS of more efficient 3 dimensions rendering compared to the possibility of ring it was.

• Journal of the Korean earth science society
• /
• v.43 no.1
• /
• pp.176-187
• /
• 2022

Due to recent mid-scale earthquakes in the Korean Peninsula, the Korean central and local governments are preparing new measures for earthquake hazard mitigation. Geological and geotechnical information is essential for earthquake hazard assessment. Thus, related data have been collected and assimilated as DBs by various national organizations. However, several problems arise when local governments intend to use this information to establish earthquake hazard mitigation measures. In the case of the geological information, small-scale geological maps make it difficult to acquire detailed information, whereas lithofacies and faults do not often match at the boundaries of large-scale geological maps. Significant geotechnical information is lost due to lack of digitalization. Present study proposes four policy plans for geological and geological information management. First, it is necessary to link industry-academictechnology fields to use the information that has already been or to be produced more efficiently and professionally. Second, local government regulations are required to be enacted and revised to accumulate a lot of geological and geotechnical information. Third an expert system should be prepared to improve the quality of the information. Fourth, it is necessary to establish a dedicated department and expand budget support for efficient information management.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.44 no.3
• /
• pp.23-30
• /
• 2007

RFID it reads information which is it writes, the semiconductor chip for and the radio frequency system which uses the hazard antenna it has built-in transmission of information it talks. Formation which is transmitted like this collection and America which it filtrates wey the RFID search service back to inform the location of the server which has commodity information which relates with an object past record server. The hazard where measurement analysis result the leader for electronic interference does not occur consequently together from with verification test the power level which is received from the antenna grade where it stands must maintain minimum -55dBm and the electronic interference will not occur with the fact that, antenna and reel his recognition distance the maximum 7m until the recognition which is possible but smooth hazard it must stand and and with the fact that it will do from within and and and 3-4m it must be used Jig it is thought.