• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.9
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• pp.1373-1378
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• 2017

This paper presents a basic ECU(Electronic Control Unit) hardware development procedure for the functional safety of in-vehicle network systems. We consider complete hardware redundancy as a safety mechanism for in-vehicle communication network under the assumption of the wired network failure such as disconnection of a CAN bus. An ESC (Electronic Stability Control) system is selected as an item and the required ASIL(Automotive Safety Integrity Level) for this item is assigned by performing the HARA(Hazard Analysis and Risk Assessment). The basic hardware architecture of the ESC system is designed with a microcontroller, passive components, and communication transceivers. The required ASIL for ESC system is shown to be satisfied with the designed safety mechanism by calculation of hardware architecture metrics such as the SPFM(Single Point Fault Metric) and the LFM(Latent Fault Metric).

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.4
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• pp.257-267
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• 1997

This study focuses on the health risk assessment of airborne volatile organic compounds (VOCs) in a petrochemical complex, with several emphases on a risk assessment method. The first emphasis is on the importance of hazard identification to determine the likely carcinogenic potential of a VOC. Without considering this type of information, a direct comparison of the carcinogenic risks of two pollutants is meaningless. Therefore, wer suggest that this type of information be prepared and be listed with the estimate of cancer risk in parallel. The second emphasis is on the selection of a better dose-response model to estimate unit risk or cancer potency factor of a carcinogenic VOC. Finally, probilistic risk assessment method is discussed and recommended to use within a comparison of conventional point-estimate method. A health risk assessment has also been carried out. For non-carcinogenic risk, even the highest hazard index for carbon tetrachloride is estimated to be less than 1 with the other VOCs less than 0.03. However, the lifetime cancer risk from the inhalation of airborne VOCs is estimated to be about $2.6 \times 10^{-4}$ which is higher than the risk standard of $10^{-6}$ or even $10^{-5}$. Therefore, the investigation into domestic petrochemical complexes should be strengthened to obtain more fine long-term airborne VOC data.

• Journal of the Korean Society of Hazard Mitigation
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• v.5 no.1 s.16
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• pp.63-68
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• 2005

LSIV (Large Scale Image Velocimetry), a technique of image analysis on velocity measurement, was applied to a hydraulic model experiment of river confluence. The surface velocities measured by using LSIV showed similar results with the mean velocities by using a traditional velocimeter, While a general velocimeter can measure only local point velocity, LSIV can measure whole velocity field with one shot. When it is applied to river confluence or around a bridge pier where local flow is dominant, LSIV may be a powerful tool to measure velocity field.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.111-118
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• 2003

Kangwon province has been suffering from the various types of disasters and these disasters stand in the way to sustainable development. The heavy rainfall by typhoon RUSA in 2002 and HAEMI in 2003 damaged to property and bodily injury, and gave us a lesson. Even if the refuge activities plan by local government plan for disaster were established with rainfall event, it could not its role in practice. Beside it, the potential disaster risk remains still in existence because the disaster restoration work aims to original state. Therefore, in this study we focused on the point at issue of disaster countermeasure plan by local government and its integrated plan considering local characteristics.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.137-147
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• 2008

The relative magnitudes of the individual terms of the momentum equation are analyzed and compared by analytical methods. The temporal variations of each term are analyzed for the influence factors to runoff expressed by the parameters of the momentum equation, stream slopes and roughness coefficients. The magnitudes of local acceleration and convective acceleration offset each other. The peak time of each term except the gravity term coincides with inflection point of the hydrograph rising limb each other. The magnitudes of each term vary with the channel characteristics, especially when the roughness coefficients are dominant or for the mild stream slopes the pressure term can not be negligible.

• Journal of Advanced Navigation Technology
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• v.20 no.1
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• pp.1-7
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• 2016

Since 2014, MOLIT (Ministry of Land, Infrastructure, and Transport) is carrying out a KASS project to develop and construct Korean SBAS. KASS can cause damage of human & properties if it has some problem during operation. Therefore, system safety assessment for KASS development is very important. Principal point of system safety assessment is the allocation of DAL(design assurance level) based on the hazard identification and classification. In this parer, the author conducts the allocation of DAL for KASS & its sub-systems based on the international standard(SAE ARP4761), which suggests a best practice of aviation system safety assessment. The result of this paper are the first step of system safety assessment, and can be used for further system safety assessment of KASS project.

• Fire Science and Engineering
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• v.25 no.3
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• pp.107-112
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• 2011

We have considered the fire hazard by the static in anti-static film manufacturing factory on this study. Solvents that the flash point as ethanol, methanol and iso-propyl alcohol is low are used on the manufacturing process of anti-static film, and the minimum ignition energy of these solvents is ignited easily despite less discharge energy form 0.16 mJ to 0.65 mJ. After the static electric potential produced on each of the manufacturing plants was measured, electric potential on films of paste board is measured form 17 kV to 20 kV. But this exceeds 5 kV, which is electrifiable of objective of nonconductor for fire & explode protection. Therefore, We figure out the fire hazard was high by a static discharge in anti-static film manufacturing factory.

• Korean Journal of Remote Sensing
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• v.34 no.1
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• pp.45-74
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• 2018

Landslide is a natural hazard that threats lives and properties in many areas around the world. Landslides are difficult to recognize, particularly in rainforest regions. Thus, an accurate, detailed, and updated inventory map is required for landslide susceptibility, hazard, and risk analyses. The inconsistency in the results obtained using different features selection techniques in the literature has highlighted the importance of evaluating these techniques. Thus, in this study, six techniques of features selection were evaluated. Very-high-resolution LiDAR point clouds and orthophotos were acquired simultaneously in a rainforest area of Cameron Highlands, Malaysia by airborne laser scanning (LiDAR). A fuzzy-based segmentation parameter (FbSP optimizer) was used to optimize the segmentation parameters. Training samples were evaluated using a stratified random sampling method and set to 70% training samples. Two machine-learning algorithms, namely, Support Vector Machine (SVM) and Random Forest (RF), were used to evaluate the performance of each features selection algorithm. The overall accuracies of the SVM and RF models revealed that three of the six algorithms exhibited higher ranks in landslide detection. Results indicated that the classification accuracies of the RF classifier were higher than the SVM classifier using either all features or only the optimal features. The proposed techniques performed well in detecting the landslides in a rainforest area of Malaysia, and these techniques can be easily extended to similar regions.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2030-2036
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• 2016

This paper presents a hardware development procedure of the ASB(Active Seat Belt) control system to comply with ISO 26262. The ASIL(Automotive Safety Integrity Level) of an ASB system is determined through the HARA(Hazard Analysis and Risk Assessment) and the safety mechanism is applied to meet the reqired ASIL. The hardware architecture of the controller consists of a microcontroller, H-bridge circuits, passive components, and current sensors which are used for the input comparison. The required ASIL for the control systems is shown to be satisfied with the safety mechanism by calculation of the SPFM(Single Point Fault Metric) and the LFM(Latent Fault Metric) for the design circuits.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.6
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• pp.107-115
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• 2010

This study was surveyed to identify changes of flora during three years after restoration in Cheonggyecheon stream. There are four sections in Cheonggyecheon. One and two sections are upper streams and three and four sections are down streams. It was surveyed 328 species in 2006. In 2007 and 2008, 446 and 444 species were found, respectively. This result shows that Cheonggyecheon is unstable initial condition in restored stream ecosystem. Naturalized species were 58 species in 2006 and it was respectively 61 and 63 species in 2007 and 2008. Hazard species of ecosystem were three common species during survey period. In appearance of flora per section, three and four sections constituted by natural sites such as point bars, wide flood plains, riffles and ponds, marshes, etc. were surveyed more species than one and two constructed by concrete materials and narrow flow channel. Recently, as time goes by, introduced species are being increased. And succession has mainly been progressed by one year or binary herbs and perennial herbs. Compared with other restored streams, Cheonggyecheon showed more flora than Yangjaecheon and Anyangcheon. It is judged owing to length of surveyed site, various planted species and area of inhabitation space. To manage restored stream ecosystem, monitoring is essential. Further, because change of vegetation after restoration in Cheonggyecheon is very important, continuous monitoring about Flora and Naturalized species and Hazard species of ecosystem is also very important.