• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.467-472
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• 2010

In this study, an analysis of the used RCD's condition is conducted to assess the effect on environment of installation area, terms of use, corrosion, contamination etc. According to KS C 4613, the used RCDs were tested to get date which is the RCD's life time. And then, the date is analysed using Minitab which is a statistical program for reliability analysis. As a result, The RCD's MTTF for the all samples is $12.7{\pm}0.23$ years. and the MTTF of RCDs which are used indoor area is $12.9{\pm}0.34$ years, the MTTF of RCDs which are used outdoor area is $11.9{\pm}0.30$ years. Futhermore, the MTTF of RCDs which are used in dry area is a $13.1{\pm}0.26$ years, the MTTF of RCDs which are used in dust area is $13.0{\pm}0.57$ years, the MTTF of RCDs which are used in moisture area is $8.4{\pm}0.77$ years.

• Journal of the Korean Society of Safety
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• v.37 no.6
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• pp.25-31
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• 2022

In this study, the spill and leak system is developed to provide real-time remote monitoring of industrial complexes where chemical accidents have been occurring every year. The spill and leak monitoring system uses IR-RCD equipment mounted on a 70m-high steel tower to detect chemical substances, thereby detecting chemical accidents such as leaks, fires, and explosions in real time. If IR-RCD equipment can actually detect chemical substances at a long distance, accurate and rapid initial response can be expected. Therefore, in order to confirm that IR-RCD equipment can detect chemical leakage accidents occurring at a long distance, acetone was selected as the experimental substance and a detection experiment was designed. The experiment was conducted using the acetone pool evaporation method at the wharf which was located 1.5 km away from IR-RCD equipment, and it was confirmed whether IR-RCD equipment could detect acetone in real time through the control monitor.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.279-281
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• 2012

CE RCD(Recreational Craft Directive, 2003/44/EC)는 24미터 미만의 레저선박을 포함하는 수상레저기구에 대한 설계, 생산 그리고 그 품질에 대한 규격을 정의하고 있는 EU 지침(European Directive)으로써, 유럽공동체는 물론이고 이를 인정하는 국가에 레저선박을 수출, 유통하기 위해서는 반드시 획득해야하는 인증규격이다. 국내의 경우 등록 및 검사에 있어 비교적 간소한 절차를 필요로 하는 소형 파워요트를 중심으로 레저선박 개발이 이루어져 왔으며, 이러한 국제인증에 기반한 설계, 생산기술에 대한 연구가 부족한 실정이다. 본 연구에서는 CE RCD의 평가 모듈과 절차를 분석하고 이를 레저보트 개발에 효과적으로 적용하기 위한 방안을 연구하였으며, 50피트급 레저보트 설계 사례연구를 통해 그 효용성을 보였다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.232-237
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• 2010

Fault rate of RCD is increasing due to deterioration and long period usage in domestic. According to Korean standards, the RCDs are installed in panel boards. When RCDs are installed at outdoor, the RCDs must be protected from uv, water etc. by using the housing. However, many RCDs are exposed to the external environment. As a results, many RCDs have malfunctions so that cause the electrical accidents. The RCDs manufactured by four makes were used as the sample to weathering test. Futhermore, those were analyzed the ingredients of RCD'S using SEM, EDX and FT-IR/TAR before and after weathering test.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.556-559
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• 2009

Compounds extracted from Platycodon grandiflorum were evaluated for an activation effect on nuclear factor-kappa B (NF-${\kappa}B$). In its active state, NF-${\kappa}B$ turns on the expression of genes related to cell proliferation or death. NF-${\kappa}B$ activators promote growth of neuron cells and can be used to control neurodegenerative diseases. The biological activity of P. grandiflorum extracts toward NF-${\kappa}B$ had not yet been studied. Although the biological activity of several compounds extracted from P. grandiflorum was evaluated, only three exhibited any significant activation effect on NF-${\kappa}B$.

• Journal of the Korean institute of surface engineering
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• v.47 no.6
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• pp.335-340
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• 2014

This study selected an outdoor RCD'S and verified behavior of change in the housing with time. Weathering tests were carried out as outdoor exposure test (90 degrees, 37 degrees) and laboratory test (xenon lamp), and the results were evaluated based on color difference, gloss, contact angle, and optical microscope. This study can provide basic data for standardization of development and performance evaluation on RCD'S housing products.

• Magazine of the Korea Concrete Institute
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• v.23 no.6
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• pp.60-63
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• 2011

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.3
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• pp.301-312
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• 2017

CE RCD (Recreational Craft Directive) is a certification for the design and construction of small vessels, including pleasure yachts, which are widely used not only in the countries within the European Union, but also in Japan and Southeast Asia. Recently, South Korean leisure craft shipyards have developed interest in exporting to foreign leisure craft markets such as Europe; however, they have encountered difficulties because of the CE RCD regulations, which are relatively complex and difficult to understand. The requirements for buoyancy and stability, which are essential properties that must be understood within the early stage of ship design, are defined based on ISO 12217. However, preparing this assessment according to ship classification regulations is an exceedingly complex task, even with knowledge of naval architecture. In this research, we have developed design support tools to systematically support assessments and preemptively define design information so that buoyancy and stability assessments based on ISO 12217 can be systematically prepared. Our research results were applied to actual examples of yacht design to confirm validity. We believe that the improved yacht design process presented in this research can act as a foundational reference for enhancing the effectiveness and systematic buoyancy and stability assessments.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.69-73
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• 2005

The arc dispersion and contacts characteristics were analyzed according to switching off Residual Current Protective Device(RCD) switch. Arc dispersion process was taken by high speed imaging system at a rate of 10,000 frames per second. When RCD was switched from on to off, art was observed and it took about 2.3[ms] from the generation of arc to the extinction of arc. When RCD was switched from off to on, arc was not observed. We repeated switching on and off 1000, 3000 and 6000 times. After repetition, the surface characteristics of contacts were taken by stereo microscope and Scanning Electron Microscope(SEM). From the scattering patterns analysis of arc and the analysis of deteriorated contacts, it could be applicable to the research of electric fire and arc suppression.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.198-207
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• 2008

The conventional Residual Current Protective Devices(RCD, or earth leakage circuit breaker, ELB) operates depending on the total leakage current which is the vector-sum of resistive and capacitive components of a leakage current. However, the electric disaster such as electric shock or fire is mainly caused by the resistive component. Therefore, in this view point, the RCD is more realistic when it operates by the resistive component of the leakage current. In this paper, a new algorithm for measuring the resistive leakage current from the total leakage current is suggested, and is realized to an actual circuit. According to the suggested algorithm, the resistive component of the leakage current can be found by integrating the total leakage current over only a half cycle of the line voltage, and it is realized by using analog switches and resettable integrators. It is confirmed through experiments that the suggested algorithm detects, within maximum average error of 6.74%, the resistive leakage current from the total leakage current, and the RCD employing the suggested algorithm brakes the circuit within the regular interrupt time(30msec).