• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.1
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• pp.85-92
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• 2011

The role of RCDs(Residual Current Protective Device) that are installed before the load is very important for preventing electric shock and electrical fire. However, although fault rate of RCD is increasing due to deterioration and long period usage, the RCD is permanently used without a checking of performance evaluation and it causes the electrical accident. In this paper, the amount of airborne chloride is researched in domestic costal area and the accelerated life test is conducted using a salt water spray tester in order to decide the life time of RCD. Aa a result of an accelerated life test, the MTTF(Mean Time To Failure) of RCD is 110.81 hours and B10 life time of RCD is 45.81 hours for the all samples. when an accelerated life test result is applied to within 2 km costal area, the life time of RCD is predicted about 5 years.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.1
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• pp.37-41
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• 2020

The Nuclear containment building is a main safety-related structure that performs shielding and conservation functions to prevent highly radioactive materials from leakage to the outside environment in the case of various environmental conditions and postulated accidents. The containment building contains a reactor, steam generator, pressurizer, tank, reactor coolant system, auxiliary system and engineering safety system, and is designed so that highly radioactive materials above the limits specified in 10 CFR 100 do not escape to the outside environment in the case of LOCA(Loss of Coolant Accident) for instance. The containment metal liner plate(CLP) is a carbon steel plate with a nominal plate thickness of 6 mm, which functions as a mold for the wall and dome of the containment building when concrete is filled, fulfills airtightness to prevent leakage of seriously radioactive materials. In recent years, backside corrosion was found on the liner plate in some domestic nuclear power plants. The main cause of backside corrosion was unfilled concrete. In this paper, an inspection technique of assessing filling suitability for CLP backside concrete is developed. Results show that the validity of inspection technique for CLP backside concrete using vibration sensor is successfully verified.

• Transactions of Materials Processing
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• v.27 no.4
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• pp.201-210
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• 2018

An airbag is an essential automotive component used in all kinds of vehicles such as an internal combustion engine and an electric motor vehicle and is used to minimize the damage of an occupant in the event of an accident. Airbag-related parts are being monopolized by a small number of foreign companies around the world. In this situation, it is necessary to develop and research the airbag-related part molding technology for expansion of the domestic airbag-related market and corporate export. As a part of this research, we have developed a mold for airbag inflator cap. The development consists of three steps which are the design of components, analysis of the design and verification of it. In the case of the design, the transfer type mold was designed for the multi-cylindrical shaped feature. Analysis was then conducted on the design. By examining the results of analysis, changing features and numbers of punches and dies were added in the analysis and repeatedly analyzed. After the addition, proper dimensions from the analysis were achieved, and prototypes were practically produced and verified. In the case of prototype verification, Pressurizing Burst Test was conducted on the existing products and the prototype. By comparing the results of the test, the possibility of replacing the existing product of the airbag inflator cap is presented in this paper.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.4 no.2
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• pp.197-209
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• 2009

Objectives : The purpose of this study is finding tendencies of diagnosis and treatment of the traffic accidental patients. Methods : We reviewed and analyzed all theses published by Korean research institution. And these theses were classified by year, field of study, reviewed by focusing on diagnosis and evaluation, treatment type. Results : 1. 72 articles were published since 1993. 2. Classified by the major field of study, the korean academy of oriental rehabilitation medicine accounted for 33 papers. 3. 7-Zone-Diagnostic system and Minnesota Multiphasic Personality Inventory were studied mostly. 4. To add pharmacopuncture or chuna treatments are effective. 5. Traffic accidental patients get satisfaction about Oriental medicine therapy but methods of medical treatment are restrictively. Conclusions : Oriental medicine treatment is the effective way to cure traffic accidental sequela, but we need further studies.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.4 s.70
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• pp.373-383
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• 2005

The cask is used to transfer the radioactive material in various fields required to withstand hypothetical accident condition such as 9m drop impact in accordance with the requirement of the domestic requlations and IAEA. So far the impact force has been obtained by the finite element method with complex computational procedure. In this study, the dynamic impact response of the cask body is analyzed using the mode superposition method, and the analysis method is proposed. The results we also validated by comparing with previous experimental results and finite element analysis results. The present method Is simpler than finite element method and can be used to predict the global impact response of cask

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.267-270
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• 2013

Hacking damage is increasing year by year in the Internet payment service credit card applying the digital signature method of PKI-based first domestic, secure payment, was 180 million won in 2012. Revenues have soared for phishing that Smishing using smartphone after entering 2013. Hacking accident to the secure payment system using Smishing has occurred took over personal information and financial direct damage. In this paper, we analyzed for Smishing, to prevent the damage of secure payment using Smishing to study the hacking attack of secure payment. In addition, it would be studies to allow through the smartphone, online payment safer and more convenient.

• The KIPS Transactions:PartD
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• v.14D no.4 s.114
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• pp.363-372
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• 2007

Password, a traditional user confirmation method that is used for more than 100 years, has become useless as a lot of transactions are dealt by indirect contacts. As a result, an alternative for password is required now. In this paper, we propose a novel confirmation method, which is called Brain-Key. It uses an indirect password input method. It reduces the risks due to hacking, and prevents a big credit accident because it prevents passwords to be reused. Our proposed model has general applicability so that it can be applied in domestic market as well as international markets. This research may provide solutions for the security problems in the electronic commerce.

• Journal of the Korea Safety Management & Science
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• v.18 no.2
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• pp.37-46
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• 2016

Due to increased demand for remodeling and repair in construction market in recent year, the usage of horse scaffold is increasing in the indoor finish works. Injuries related horse scaffold are mainly caused by poor installation or of careless handling of scaffold. Approximately 300 workers are injuried at construction site every year, it is accounting for about 1.5% of the total construction sector and has increased on a year-to-year trends. But the main contents between national standards and speccifications related to the manufacture and usage of horse scaffolds are mutually inconsistent, In particular, the rules on occupational safety and health standards are the basis for the prevention of industrial injuries, there is no explicit application being made to the horse scaffold commonly used on construction sites. The purpose of this study was to analye the manufacture and usage situations in order to reduce construction injuries that occur at the horse scaffolds. It will be utilized the results of the analysis as the basis data for unifying the major domestic standards and specifications associated with the manufacture and usage of horse scaffold.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.6
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• pp.157-167
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• 2008

Through this study, the standard design guidelines for high speed train with power cars have been derived to meet the crashworthiness requirements of the Korean rollingstock safety regulation. The crashworthiness regulation requires some performance requirements for two heavy collision accident scenarios; a train-to-train collision at the relative speed of 36 kph, and a collision against a standard deformable obstacle of 15 ton at 110 kph. A standard high speed train composition was defined as 2PC-2ET-6T with 17ton axle load, similar to KTX-2 for the Honam express line. Using theoretical and numerical analyses, some crashworthy design guidelines were derived in terms of mean crush forces and energy absorptions for major crushable components. The derived design guidelines were evaluated and improved using one dimensional spring-mass dynamic simulation. It is shown from the simulation results that the suggested design guidelines can easily satisfy the domestic crashworthiness requirements.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.87-96
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• 2015

This study analyzed the safety management efficiency through input-oriented BCC Model using DEA by making of Models, in which this study selected the number of staff affiliated with the construction site, number of staff members on the construction team, and number of safety personnel as Input Factor, along with the number of disaster victims and zero-accident accomplished hours as output elements, targeting 40-or-so apartment building construction sites which are being built by 3 domestic construction companies. As a result of efficiency, it was 0.643, the number of efficient DMU was 4. In the aspect of returns to scale, 21 construction sites(52.5%) found to be in a state of increasing returns while 14 construction sites(35%) was in a state of Decreasing returns. The reason for inefficiency was found to lie in technical factors in case of 30 construction sites(75%). Lastly, inefficient DMU is in need of 38.9 % and 66% reduction in site personnel and safety personnel. Based on study results, the 29 construction sites accounting for 72.5% of DMU for safety management efficiency evaluation object turned out to do inefficient safety management that doesn't fit the size of each company.