• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.154-157
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• 2003

In order for testing faults of combinatorial logic circuit, the authors have developed a new diagnosis method: "Neural Network (NN) fault diagnosis", based on fm error back propagation functions. This method has proved the capability to test gate faults of wider range including so called SSA (single stuck-at) faults, without assuming neither any set of test data nor diagnosis dictionaries. In this paper, it is further shown that what kind of fault models can be detected in the NN fault diagnosis, and the simply modified one can extend to test delay faults, e.g. logic hazard as long as the delays are confined to those due to gates, not to signal lines.

• Earthquakes and Structures
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• v.15 no.3
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• pp.253-261
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• 2018

This article details a bridge-specific fragility method developed to enhance the seismic design and resilience of bridges. Current seismic design processes provide guidance for the design of a bridge that will not collapse during a design hazard event. However, they do not provide performance information of the bridge at different hazard levels or due to design changes. Therefore, there is a need for a supplement to this design process that will provide statistical information on the performance of a bridge, beyond traditional emphases on collapse prevention. This article proposes a bridge-specific parameterized fragility method to enable efficient estimation of various levels of damage probability for alternative bridge design parameters. A multi-parameter demand model is developed to incorporate bridge design details directly in the fragility estimation. Monte Carlo simulation and Logistic regression are used to determine the fragility of the bridge or bridge component. The resulting parameterized fragility model offers a basis for a bridge-specific design tool to explore the influence of design parameter variation on the expected performance of a bridge. When used as part of the design process, these tools can help to transform a prescriptive approach into a more performance-based approach, efficiently providing probabilistic performance information about a new bridge design. An example of the method and resulting fragility estimation is presented.

• Architectural research
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• v.14 no.3
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• pp.99-108
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• 2012

An innovative multi-story Semi-Active Tuned Mass Damper (SATMD) building system is proposed to control seismic response of existing structures. The application of adding new stories as large tuned mass and semi-active (SA) resettable actuators as central features of the control scheme is derived. For the effective control of the structures, the optimal tuning parameters are considered for the large mass ratio, for which a previously proposed equation is used and the practical optimal stiffness is allocated to the actuator stiffness and rubber bearing stiffness. A two-degree-of freedom (2-DOF) model is adopted to verify the principal efficiency of the suggested structural control concept. The simulations for this study utilizes the three ground motions, from SAC project, having probability of exceedance of 50% in 50 years, 10% in 50 years, and 2% in 50 years for the Los Angeles region. 12-story moment resisting frames, which are modified as '12+2' and '12+4' story structures, are investigated to assess the viability and effectiveness of the system that aims to reduce the response of the buildings to earthquakes. The control ability of the SATMD scheme is compared to that of an uncontrolled and an ideal Passive Tuned Mass Damper (PTMD) building system. From the performance results of suggested '12+2' and '12+4' story retrofitting case studies, SATMD systems shows significant promise for application of structural control where extra stories might be added.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.53-59
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• 2006

Standard safety management costs can not be applied to each site with same rate, it is very difficult, because it depends on the experience, work method, work kind, work progress schedule, and hazard level of each construction company. Therefore, this study is to find out hazard level of each work kinds through questionnaire and interview and investigate analyze the status which standard safety management costs have been used. Also, this study is to show reasonable rates of standard safety management costs in construction industry and to set up countermeasures against those problem after reviewing its status in korea with in Japan and Europe. The domestic system of standard safety management costs is not considered in the foreign country, while only related subjective items have been investigated and evaluated for this study. This study is to investigate eleven project kinds of domestic system, first, and to investigate eleven items of apartment bldg, office, civil work such as bridge, tunnel, dam, plant etc, secondly. Additionally, three items of gymnasium, railway, particular steel tower are investigated in this study. Also this study is to investigate and analyze performed costs of presently processing worker finished work so that it shows a new reasonable rate against standard safety management costs in construction industry, in order to make basial data and material to be systemized.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.123-133
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• 2003

A practical statistical approach that can be used to model various sources of uncertainty systematically is presented in the context of reliability analysis of slope stability. New expressions for probabilistic characterization of soil properties incorporate sampling and measurement errors, as well as spatial variability and its reduced variance due to spatial averaging. The stochastic nature of seismic loading is studied by generating a large series of hazard-compatible artificial motions, and by using them in subsequent response analyses. The analyses indicate that in a seismically less active region such as the Korean Peninsular, a moderate variability in soil properties has an effect as large as the characterization of earthquake hazard on the computed risk of slope failure and excessive slope deformations.

• Journal of the Korean Society of Safety
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• v.28 no.6
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• pp.90-96
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• 2013

Since the last 50 years, the terminology 'risk' has been widely used in general and industrial applications, with different meanings. The different definitions of risk can lead to the different risk assessments and risk management process elements, and the misunderstandings. For the reasons, the ISO(International Standard Organization) has recently defined a new risk concept through the publication of IS0 31000:2009. Although the new concept of risk was globally accepted, it seem to be argued in its definition debate. Thus, this paper reviews the definition and meaning of the concept of risk in terms of risk origin, general and industrial applications, related domestic laws and risk management standards published to improve an understanding of risk concept.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.421-423
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• 2008

The development of remediation technologies in the contaminated coastal area from oil spill is essential for solving environmental disaster. Many countries including USA, France and United Kingdom have tried to make novel remediation techniques and predict oil dispersion in the ocean and coastal line by using their own models. To develop new technology of remediation, this research in advance was carried out the status of domestic and international remediation technologies and tried to suggest future research plan for developing new remediation technologies considering geographical characteristics of Korea peninsula.

• Analytical Science and Technology
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• v.21 no.6
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• pp.543-552
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• 2008

This paper described the relatively sensitive and simultaneous analytical method for 3-monochloropropane-1,2-diol (3-MCDP, $C_3H_7ClO_2$, MW. 110) as well as 1,3-dichloropropan-2-ol (1,3-DCP, $C_3H_6Cl_2O$, MW. 128) in various foods. Food samples were homogenized in 5M NaCl solution, mixed with aluminum oxide and eluted with dichloromethane. The extracted chloropropanols were concentrated by rotary evaporator and $N_2$ blow serially were derivatized with HFBA (Heptafluorobutyric anhydride, $C_8F_{14}O_3$, MW. 410) and were determined by GC/MS using isotope dilution method. The characteristic molecular ions at m/z 253, 275, 289, 291, and 453 for HFBA derivatives of 3-MCPD (MW. 502) and 110, 275, and 277 for HFBA derivatives of 1,3-DCP (MW. 325) were chosen in selected ion mode. The method validation data showed sufficiently good properties of LOD (0.003 mg/kg), LOQ (0.010 mg/kg), linearity ($R^2{\geq}0.999$ at 0.010~1.000 mg/kg), and recovery rate (${\approx}97%$). The levels of chloropropanols in soy sauce, sauces, processed meat products, fishery products, and seasonings (n=56/157) determined by the presented method were 0.0~0.3 mg/kg.

• Journal of the Korean Professional Engineers Association
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• v.44 no.4
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• pp.34-38
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• 2011

Following the relocation of the Korea Food and Drug Administration(KFDA) to the Osong Bio-Health Technopolis in 2011, KFDA established 6 development strategies for Global Top 5 by 2020. 6 detailed strategies aim at systematic support for corresponding to the necessity of risk management and an instantaneous response according to environmental changes which have ever-present hazard, and to the development of Fusion Technology-combined new technology. These comprehensive strategies pursue to improve the quality of national life through wise food and drug consumption. Contents for future development is a summary of KFDA's Major Work Plan 2011 related food safety policies. The plan was released in reception hall of the Blue House on Dec. 22, 2010.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.131-134
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• 2008

Increasing the need of national safety management system in order to an epoch-making improvement to scientific disaster management which appears new types of disasters through the exchange of traditional disaster environment and responds actively to the rapid exchange of social environment based on u-IT. Requiring the development of systematical information sharing networking system and sharing realtime data amongst government, local authorities and related organisations under both safety management in normal times and circumstance management in disaster times, and need for the establishment of national safety strategy, which has been strengthened function such as prevention and preparation. This research provides a basic scheme and strategic tasks in order to constitute preventing scientific national disaster prevention structure at anytime and anywhere from disaster which is based on ubiquitous technology and realise the intelligent national disaster prevention system of u-safe Korea.