• Journal of the Korean Society of Safety
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• v.35 no.1
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• pp.1-11
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• 2020

Article 325 (Prevention of Fire Explosion due to Electrostatic) of the Rule for Occupational Safety and Health Standard specifies that in order to prevent the risk of disasters caused by static electricity, fire, explosion and static electricity in the production process, However, in order to do this, it is absolutely necessary to use a pre-detection technology and a detector for antistatic discharge prediction, which is a precautionary measure by static electricity in a fire / explosion hazard place, but in Korea, And there is no technical standard for the application of the technology of the explosion proof structure of the related equipment. Research methods include domestic and overseas electrostatic discharge detection technology and literature investigation of related equipment explosion proofing technology, domestic and foreign electrostatic discharge detection device production and use situation investigation, advanced foreign technology data analysis and benchmarking. In particular, we sought to verify the results of empirical experiments using electrostatic discharge detection technology through sample purchase and analysis of related major products, development of optimization technology through prototype production, evaluation, and supplementation, and expert knowledge through expert consultation. The results of this study were developed and fabricated two prototypes of electrostatic discharge detector based on the technology / standard related to electrostatic discharge detection technology in Korea and abroad through development of electrostatic discharge detection technology and development and production of detector. In addition, based on the development of electrostatic discharge detection technology, we developed an intrinsic safety explosion proof ib class explosion proof technology applicable to the process of using and handling flammable gas and flammable liquid vapor and combustible dust. In the case of the over voltage and minimum voltage are supplied to the explosion-proof structure ESD detector, check the state of the circuit and the transient and transient currents generated by the coil and capacitor elements during the input and standby of the signal pulse voltage. Explosion-proof equipment-Part 11: Intrinsically safe explosion proof structure The comparative evaluation with the reference curve in Annex A of "i" confirms that the characteristics of the intrinsically safe explosion protection structure are met.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.33-38
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• 2013

For the safe handling of 3-hexanone(ethyl propyl ketone), this study was investigated the explosion limits of 3-hexanone in the reference data. The flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash points of 3-hexanone by using closed-cup tester were experimented at $18^{\circ}C$. The lower flash points of 3-hexanone by using open cup tester were experimented in $27^{\circ}C{\sim}32^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for 3-hexanone. The experimental AIT of 3-hexanone was at $425^{\circ}C$. The lower explosion limit( LEL) by the measured lower flash point of 3-hexanone was calculated as 1.21 Vol%.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.22-27
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• 2014

The market of performance arts industry such as concert, musical and opera etc is now expanding in Korea. However, the inadequate safety management in theatres often causes some accidents. The guarantee of safety in theatres is very important since the accidents in theaters can lead to many casualties and serious property damages. In particular, the small theatres which have no obligation of safety inspection by law are very vulnerable to safety mattes. This study has done the research into the improvement of safety in small theaters through the inspection and analysis of their safety status. For the purpose, this study has inspected and analyzed the safety status of small theaters over 120 in the field of theater management and operation, fire protection, electrical facilities, ceiling structure and etc. Moreover, this study had investigated the law and technical standards related to theatre safety. This study shows that the essentials to make sure of the safety in small theaters are (1) the education to improve the sense of security of people who work in theaters (2) the training to strengthen the operating skills of the facilities in theaters (3) the cooperation and support of the related organization such as technical research center, central and local government.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.342-351
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• 2000

The paper is concerned about the discovery of new physics of the old oriental philosophy of the yin-Yang '||'&'||' five elements. the physical properties of Five Elements are defined, similarly as in thermodynamics, as five different characteristic state in a cyclic system of nature or a human body. Wood is defined as "warm and soft", Fire as "hot and dispersive", Earth as "agglomerating and sticky", Metal as "tensile and crystallizing", and Water as "cool and slippery" state, respectively. Based on the physics of Five Elements and Qi channel theory, five different constitution classification s are made according to the shape of human face, such as long, inverse triangle, circle, square, and triangle geometry, respectively.Since the constitution implies the relative size or strength of 5 major organs, this theory can be applies successfully to the prediction of the susceptibility to specific diseases as well as the analyses of personal character such as emotion and sensibility. The specific character is analyzed with four different aspects; that is, the first and second are caused by the positive and negative side of the strongest organ, the third character by determined the weakest organ, and finally the fourth by the abnormal psychology due to serious illness.bnormal psychology due to serious illness.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.346-351
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• 2020

The removal characteristics of copper (Cu) from electrochemical surface by voltage-activated reaction were reviewed to assess the applicability of electrochemical-mechanical polishing (ECMP) process in three types of electrolytes, such as HNO₃, KNO₃ and NaNO₃. Electrochemical surface conditions such as active, passive, transient and trans-passive states were monitored from its current-voltage (I-V) characteristic curves obtained by linear sweep voltammetry (LSV) method. In addition, the oxidation and reduction process of the Cu surface by repetitive input of positive and negative voltages were evaluated from the I-V curve obtained using the cyclic voltammetry (CV) method. Finally, the X-ray diffraction (XRD) patterns and energy dispersive spectroscopy (EDS) analyses were used to observe the structural surface states of a Cu electrode. The electrochemical analyses proposed in this study will help to accurately control the material removal rate (MRR) from the actual ECMP process because they are a good methodology for predicting optimal electrochemical process parameters such as current density, operating voltage, and operating time before performing the ECMP process.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.2
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• pp.70-79
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• 2020

The offshore installation units may be subjected to various accidental loads such as collision from supply vessels, impact from dropped objects, blast load from gas explosion and thermal load from fire. This paper deals with the design and strength evaluation method of the stiffened plate structures in response to a blast load caused by a gas explosion accident. It is a comprehensive review of various items used in actual project such as the size and type of the explosive loads, general design procedure/concept and analysis method. The structural analyses using simple analysis methods based on SDOF model and nonlinear finite element analysis are applied to the particular FPSO project. Also validation studies on the design guidance given by simple analysis method based on SDOF model have also considered several items such as backpressure effects, material behavior and duration time of the overpressure. A good correlation between the prediction made by simple analysis method based on SDOF model and nonlinear finite element analysis can be generally obtained up to the elastic limit.

• Journal of the Korean Institute of Gas
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• v.17 no.2
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• pp.21-27
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• 2013

The lowest values of the AITs(Autoignition temperatures) in the literature were normally used fire and explosion protection. In this study, the AITs of n-Propanol+n-Octane system were measured from ignition delay time(time lag) by using ASTM E659 apparatus. The AITs of n-Propanol and n-Octane which constituted binary systems were $435^{\circ}C$ and $218^{\circ}C$, respectively. The experimental ignition delay time of n-Propanol+n-Octane system were a good agreement with the calculated ignition delay time by the proposed equations with a few A.A.D.(average absolute deviation).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.1
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• pp.15-20
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• 2017

The summer climate is very hot and humid in Korea. The humidity is an important factor in determining thermal comfort. Recently, the research for dehumidification device development has been attempted to save energy that is required for the operation of the current dehumidifiers on the market. Existing dehumidification systems have disadvantages such as wasting energy to drive a compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature so it doesn't have to consume cooling energy. In this paper, the cooling energy savings was studied when a dehumidification system was applied in a model building instead of a chiller. The sensible heat load was almost the same result, but the latent heat load was decreased by 38.9% and the total heat load was decreased by 8.5%. As a result, electric energy used to drive the compressor in a chiller was saved by applying a membrane air-conditioning system instead.

• Journal of the Korean Institute of Gas
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• v.17 no.4
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• pp.70-76
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• 2013

For the safe handling of styrene, this study was investigated the explosion limits of styrene in the reference data. The flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. As a results, the lower and upper explosion limits of styrene recommended 0.9 Vol.% and 8.0 Vol.%, respectively. The lower flash points of styrene by using closed-cup tester were experimented $29^{\circ}C{\sim}31^{\circ}C$. The lower flash points of styrene by using open cup tester were experimented $32^{\circ}C{\sim}36^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for styrene. The experimental AIT of styrene was $460^{\circ}C$.

• Journal of the Korean Institute of Gas
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• v.19 no.2
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• pp.5-11
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• 2015

The explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. The explosion limit of aldehydes have been shown to be correlated the heat of combustion and the chemical stoichiometric coefficients. In this study, the lower explosion and upper explosion limits of aldehydes were predicted by using the heat of combustion and chemical stoichiometric coefficients. The values calculated by the proposed equations agreed with literature data above determination coefficient 0.99. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the aldehydes.