• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1602-1610
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• 2005

In this study was investigated and analyzed of damage characteristics for infrastructures by typhoon that have been many occur. The objective Structures were the road and hydraulic structure. The road structure was included the cut-slopes, retaining walls and bridges. The hydraulic structure is divided with the dike, small-scale dam, reservoir and floodgate. The analysis result of the bridge damage cause is river bottom height increase and passage ability decrease. The principal damage reasons of the cut-slope structure are weakening the ground due to the localized torrential downpour and drainage defective. Also, the principal damage reasons of the small-scale dam, reservoir, dike and the floodgate are continuous collapse of dike beside the floodgate.And we divided a typhoon damage occurrence cause with artificial and natural. As the result of analysis, the many damage occurrence cause will be removed by system improvement and technical development.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.831-837
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• 2005

In this study, a computer program to predict the behavior of laterally loaded single pile and pile groups was developed by using a beam-column analysis in which the soils are modeled as nonlinear springs by a family of p-y curves for subgrade modulus. The special attention was given to the lateral displacement of a single pile and pile groups due to the soil condition and the cap rigidity. The analysis considering group effect was carried out for $2\;{\times}\;2\;and\;3\;{\times}\;3$ pile groups with the pile spacing 3.0B, 4.0B and 5.0B. Based on the results obtained, it is found that the overall distributions of deflection, slope, moment, and shear force in a single pile give a reasonable results irrespective of cap connectivity conditions. It is also found that even though there are some deviations in deflection prediction compared with the observed ones, the prediction by present analysis simulates much better the general trend observed by the centrifuge tests than the numerical solution predicted by PIGLET.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.643-650
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• 2004

In general, slope failures are occurred by the interaction among various factors(slope shape, hydraulic condition, and geologic condition, etc.). In the area where has a heavy rainfall, a great portion of slope failures are caused by seepage increasement with suitable failure condition. Many studies have been performed to find the cause of large-scale failures. In this study, three Cut-Slope failures caused by typhoon 'MAEMI' were investigated to find out factors causing large-scale slope failures. It was confirmed in this research that major reason of slope failures was the weak layer working along with other unstable factor. The large-scaled investigation concerning Cut-Slope will be needed to find out the Weak Layer.

• 한국가스학회:학술대회논문집
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• 2000.09a
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• pp.8-13
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• 2000

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.276-280
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• 2007

In order to select the coating materials to perilla seed for reducing endosulfan residue greenhouse soil, this study was conducted to develop seed coating method and materials and also to evaluate the effects of seed coating on germination and color contrast between soil and perilla seed for convenient sowing work. Talc and kaoline were selected as seed coating materials because easy coating and better color contrast than shell powder or lime. Water was more effective on germination compared to alcohol, com oil and spray sticker as adhesives for seed coating.

• Journal of Powder Materials
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• v.31 no.2
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• pp.152-162
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• 2024

The directed energy deposited (DED) alloys show higher hardness values than the welded alloys due to the finer microstructure following the high cooling rate. However, defects such as microcracks, pores, and the residual stress are remained within the DED alloy. These defects deteriorate the wear behavior so post-processing such as heat treatment and hot isostatic pressing (HIP) are applied to DED alloys to reduce the defects. HIP was chosen in this study because the high pressure and temperature uniformly reduced the defects. The HIP is processed at 1150℃ under 100 MPa for 4 hours. After HIP, microcracks are disappeared and porosity is reduced by 86.9%. Carbides are spherodized due to the interdiffusion of Cr and C between the dendrite and interdendrite region. After HIP, the nanohardness (GPa) of carbides increased from 11.1 to 12, and the Co matrix decreased from 8.8 to 7.9. Vickers hardness (HV) decreased by 18.9 % after HIP. The dislocation density (10^-2/m²) decreased from 7.34 to 0.34 and the residual stress (MPa) changed from tensile 79 to a compressive -246 by HIP. This study indicates that HIP is effective in reducing defects, and the HIP DED Stellite 6 exhibits a higher HV than welded Stellite 6.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.47-54
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• 2014

The protection of nuclear safety software is essential in that a failure can result in significant economic loss and physical damage to the public. However, software security has often been ignored in nuclear safety software development. To enforce security considerations, nuclear regulator commission recently issued and revised the security regulations for nuclear computer-based systems. It is a great challenge for nuclear developers to comply with the security requirements. However, there is still no clear software development process regarding security activities. This paper proposes an integrated development process suitable for the secure development requirements and system security requirements described by various regulatory bodies. It provides a three-stage framework with eight security activities as the software development process. Detailed descriptions are useful for software developers and licensees to understand the regulatory requirements and to establish a detailed activity plan for software design and engineering.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.1031-1041
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• 2016

Interests in the Polar Regions have been growing due to various factors such as depletion of natural resources and advanced resource development technologies, accelerated rate of polar ice melting as a result of global warming, etc. In particular, demand for the workforce related to vessel passage using the Northern Sea Route and polar studies is still expanding. The International Maritime Organization adopted the Polar Code in 2015 for the safety of ship operation in polar waters and it will enter into force from 2017. But education and training section in the code has been prescribed only for the safe navigation in the ice covered waters intended for navigational offices. There is no basic safety training requirement that applies commonly for all personnel exposed to the risk of the polar regions and the relevant study or discussion has not been made so far. Therefore, this study provides basic data for developing safety training courses for crew and other personnel by analyzing relevant regulations on polar safety training and the contents of relevant safety training in offshore industry required by the costal states adjacent to arctic ocean.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.201-208
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• 2019

Since the introduction of the open innovation at the beginning of the 2000s, various studies have been carried out on the convergence of technologies, such as the development of new technologies and the development of the business domain. while exploring the technologies necessary for the convergence of appropriate technologies in this research, we propose a discovery process of challengeable research areas by means of the integration of heterogeneous fields which are based on the strategic formulation of ICT and chemical safety industry. In this paper, we consequently propose the 103 detailed convergent technologies based on ICT, especially including artificial intelligent technology and smart big-data platform architecture, were derived from the research areas of the chemical safety field, We expect that research related to the safety field will be frustrated in the future.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.195-204
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• 2015

The live fire test has been playing a critical role in evaluating the goals-to-meet of the weapon systems which utilize the power of explosives. As such, the successful development of the test systems therein is quite important. The test systems development covers that of ranges and facilities including system-level key components such as mission control, instrumentation or observation, safety control, electric power, launch pad, and so on. In addition, proper operational guidelines are needed with well-trained test and operation personnel. The emerging weapon systems to be deployed in future battle field would thus have to be more precise and dynamic, smarter, thereby requiring more elaboration. Furthermore, the safety consideration is becoming more serious due to the ever-increasing power of explosives. In such a situation, development of live fire test systems seems to be challenging. The objective of the paper is on how to incorporate the safety and other requirements in the development. To achieve the goal, an architectural approach is adopted by utilizing both the system components relationship and safety requirement when advanced instrumentation technology needs to be developed and deteriorated components of the range are replaced. As an evaluation method, it is studied how the level of maturity of the test systems development can be assessed particularly with the safety requirement considered. Based on the concepts of both systems engineering and SoS (System-of-Systems) engineering process, an enhanced model for the system readiness level is proposed by incorporating safety. The maturity model proposed would be helpful in assessing the maturity of safety-critical systems development whereas the costing model would provide a guide on how the reasonable test resource allocation plan can be made, which is based on the live fire test scenario of future complex weapon systems such as SoS.