• 품질경영학회지
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• 제50권1호
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• pp.125-138
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• 2022

Purpose: Failure Mode and Effect Analysis (FMEA) is a widely utilized technique to measure product reliability by identifying potential failure modes. Even though FMEA techniques have been studied, the form of Risk Priority Number (RPN) used to evaluate risk priority in FMEA is still questionable because of its shortcomings. In this study, we suggest common RPN(cRPN) to resolve shortcomings of the traditional RPN and show the extensibility of cRPN. Methods: We suggest cRPN which is based on Cobb-Douglas production function, and represent the various application on weighting risk factors, weighted RPN in a mathematical way, and show the possibility of statistical approach. We also conduct numerical study to examine the difference of the traditional RPN and cRPN as well as the potential application from the analysis on marginal effects of each risk factor. Results: cRPN successfully integrates previously suggested approaches especially on the relative importance of risk factors and weighting RPN. Moreover, we analyze the effect of corrective actions in terms of econometric analysis using cRPN. Since cRPN is rely on the reliable mathematical model, there would be numerous applications using cRPN such as smart factory based on A.I. techniques. Conclusion: We propose a reliable mathematical model of RPN based on Cobb-Douglas production function. Our suggested model, cRPN, resolves various shortcomings such as consideration of the relative importance, the effect of combinations among risk factors. In addition, by adopting a reliable mathematical model, quantitative approaches are expected to be applied using cRPN. We find that cRPN can be utilized to the field of industry because it is able to be applied without modifying the entire systems or the conventional actions.

• 한국식품영양과학회지
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• 제28권6호
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• pp.1212-1219
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• 1999

The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

• 전기학회논문지
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• 제60권4호
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• pp.862-870
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• 2011

In this paper, we introduce a new topology of Radial Basis Function-based Polynomial Neural Networks (RPNN) that is based on a genetically optimized multi-layer perceptron with Radial Polynomial Neurons (RPNs). This study offers a comprehensive design methodology involving mechanisms of optimization algorithms, especially Fuzzy C-Means (FCM) clustering method and Particle Swarm Optimization (PSO) algorithms. In contrast to the typical architectures encountered in Polynomial Neural Networks (PNNs), our main objective is to develop a design strategy of RPNNs as follows : (a) The architecture of the proposed network consists of Radial Polynomial Neurons (RPNs). In here, the RPN is fully reflective of the structure encountered in numeric data which are granulated with the aid of Fuzzy C-Means (FCM) clustering method. The RPN dwells on the concepts of a collection of radial basis function and the function-based nonlinear (polynomial) processing. (b) The PSO-based design procedure being applied at each layer of RPNN leads to the selection of preferred nodes of the network (RPNs) whose local characteristics (such as the number of input variables, a collection of the specific subset of input variables, the order of the polynomial, and the number of clusters as well as a fuzzification coefficient in the FCM clustering) can be easily adjusted. The performance of the RPNN is quantified through the experimentation where we use a number of modeling benchmarks - NOx emission process data of gas turbine power plant and learning machine data(Automobile Miles Per Gallon Data) already experimented with in fuzzy or neurofuzzy modeling. A comparative analysis reveals that the proposed RPNN exhibits higher accuracy and superb predictive capability in comparison to some previous models available in the literature.

• 한국가스학회지
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• 제13권1호
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• pp.45-51
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• 2009

본 논문은 국내에 건설된 충전소를 분석 검토하여 수소충전소에 대한 안전성 평가를 실시함으로써 수소충전 소의 안전성에 대한 확인과 충전소 설치 시 필요한 기준마련에 기초자료를 제공하는 것이 궁극적인 목표이다. 안전성 평가 방법으로 FMEA (Failure Mode and Effect Analysis)를 사용하였고, 충전소를 크게 4개의 공정(제조, 압축, 저장, 충전)으로 분류하였다. 또한 각각의 발견된 위험요소에 S (severity), O (occurrence), D (detection)의 점수를 부여하여 이 세 요소의 곱의 값인 RPN (Risk Priority Number)의 수치를 이용하여 위험의 우선순위를 정하고, 이를 바탕으로 시나리오를 생성하였다. 생성한 시나리오를 기반으로 사고피해영향평가 결과 주요한 사고 유형으로 jet fire와 폭발이 나타났고, PSA (pressure swing adsorption) 공정 feed line에서의 누출의 경우 원료물질에 따라 CO가스의 농도가 상이할 수도 있으나, CO가스중독 위험성을 함께 예측되었다.

• Journal of Pharmaceutical Investigation
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• 제40권6호
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• pp.367-372
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• 2010

Rabeprazole sodium (RPN) is known to be very unstable at acidic condition or some acidic pharmaceutical excipients such as acrylic acid polymer (carbomer 934) with carboxylic acids. Thus, degradation mechanism of binary blends of rabeprazole with pharmaceutical excipients in a solid state without using solvents at three different ratios (3:1, 1:1 and 1:3) was investigated using Fourier transform infrad (FTIR) spectroscopy. Alkalizer (MgO), neutral hydroxypropymethylcellulose (HPMC 4000) were also tested for comparison. The binary blends were stored under accelerated conditions ($40^{\circ}C$/75% relative humidity) for two weeks. The concentration of thioether rabeprazole from the binary blends with acidic carbomer 934 increased as the rabeprazole concentration decreased. In addition, the degradation half-life of rabeprazole as well as the relative peak area ratios obtained from FTIR spectra of S=O stretching at $1094.1\;cm^{-1}$ decreased consistently as the fraction of carbomer 934 increased due to its sensitivity between the basic benzimidazole nitrogen and carboxylic acid group of carbomer 934. The physical appearance also turned into strong brown color in the presence of carbomer 934. In contrast, there were no significant changes in the degradation kinetics of rabeprazole with MgO and HPMC 4000 in a solid state. This present study demonstrated that the solid-state compatibility test with the aid of HPLC chromatographic and FTIR spectral analyses could offer a valuable methodology to select suitable pharmaceutical excipients and to elucidate the degradation mechanism of RPN for drug formulations at the early formulation stages.

• 한국안전학회지
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• 제31권5호
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• pp.7-15
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• 2016

The purpose of this paper is to carry out Failure Modes and Effects Analysis (FMEA) and use criticality in order to determine risk priority number of the components of electric power installations in Engineering college building of D university. In risk priority number, GROUP A had 7 failure modes; more specifically, Transfomer had 4 modes, Filter(C)(1 mode), LA(1 mode), and CB(MCCB)(1 mode), and thus 4 components had failure modes. In terms of criticality, high-grade group a total of 16 failure modes, and 7 components-LA(1 mode), CB(MCCB)(1 mode), MOF(2 modes), PT(1 mode), Transformer(7 modes), Cable(3 modes), and Filter(C)(1 mode)-had failure modes. Comparison of risk priority number and criticality was made. The components which had high risk priority number and high criticality were Transformer, Filter(C), LA, and CB(MCCB). The components which had high criticality were MOF and cable. In particular, Transformer(RPN: 4 modes, Criticality: 7 modes) was chosen as an intensive management component.

• 원예과학기술지
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• 제30권5호
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• pp.613-616
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• 2012

The new Cymbidium variety 'Pink Glory' (Palace Court 'Jacky' ${\times}$ Lucky Rainbow 'Saint Rapine') was developed at the National Institute of Horticultural & Herbal Science, Rural Development Administration in 2006. A cross was made in 1995 between C. Palace Court 'Jacky' with a medium sized bright pink colored flowers, and C. Lucky Rainbow 'Saint Rapine' with pink colored flowers. In 1999, one line was selected based on the flower color, leaf shape, flower stalk, and vigorous growth. Evaluation and selection trials were conducted from 2000 to 2004. 'Pink Glory' has a light pink sepal (RHS, RPN66D), red lip (R52B) and a leaf length of 87.5 cm. The average number of flowers on each peduncle was 20.5 and the flower diameter was 8.6 cm. The general impression of petals and sepals showed some incurved and some spreading. 'Pink Glory' has a vigorous growth character and a rounded flower shape. It has an adequate peduncle height (66.5 cm) compared to leaf length (87.5 cm) and starts to bloom in late January under optimal cultural conditions.

• KSBB Journal
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• 제8권3호
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• pp.217-223
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• 1993

호알카리성 Alcaligenes속의 한 균종응 이용하여 peptide계 생분해성 고분자인 ${\gamma}$-PGA( p이yglutarnic a acid}의 회분 맺 연속배양어l 의한 대량 생산성을 조사하였다. 화분배양시 ${\gamma}$-PGA의 생생량 벚 생산생은 포도당 농도 50g/P 까지 포도당의 농도증가에 따라 증가하였으나 최대 생산수율은 10gjP 의 포도당 농도 에서 얻어졌으며, 이때의 수율은 63% 이였다. 또, 비 증식속도는 포도당 농도 50g/l 에셔 약 $0.25hr^{-1}$로 최대값을 나타냈으나, 이 이상의 농도에서는 고농도 기섣에 의한 균체생육의 저해륜 나타내였다. 온도, pH 및 교반속도(rpm)를 독랩변수로 한 반응표면 분 석에 의한 ${\gamma}$-PGA 생산의 최적 희분배양 조건은 배 양온도 $31^{\circ}C$, pH 10 및 회전속도 87rpm의 정상점에 서 얻어졌으며, 이 조건에서 ${\gamma}$-PGA의 생산량은 약 11g/l 로 추정되었다. 연속배양의 경우 wash out은 희석률 0.5hr-1에서 일어났으며, 희석률 $0.40hr^{-1}$일 때 최대 생산성을 나타내였고, 최대 생산생은 2.80g/l/h로 회분배양보다 약 9배 높았다.

• 한국안전학회지
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• 제36권2호
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• pp.10-17
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• 2021

This paper presents the robust design of each component used in the development of an induction bolt heating system for dismantling the high-temperature high-pressure casing heating bolts of turbines in power plants. The induction bolt heating system comprises seven assemblies, namely AC breaker, AC filter, inverter, transformer, work coil, cable, and CT/PT. For each of these assemblies, the various failure modes are identified by the failure mode and effects analysis (FMEA) method, and the causes and effects of these failure modes are presented. In addition, the risk priority numbers are deduced for the individual parts. To ensure robust design, the insulated-gate bipolar transistor (IGBT), switched-mode power supply (SMPS), C/T (adjusting current), capacitor, and coupling are selected. The IGBT is changed to a field-effect transistor (FET) to enhance the voltage applied to the induction heating system, and a dual-safety device is added to the SMPS. For C/T (adjusting current), the turns ratio is adjusted to ensure an appropriate amount of induced current. The capacitor is replaced by a product with heat resistance and durability; further, coupling with a water-resistant structure is improved such that the connecting parts are not easily destroyed. The ground connection is chosen for management priority.

• 대한안전경영과학회지
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• 제25권3호
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• pp.73-81
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• 2023

This study uses FMECA (Failure Modes, Effects, and Criticality Analysis) and HAZOP (Hazard and Operability), which are widely applied in industrial areas, among risk assessment methods, and applies them to the same system. While FMECA evaluates system failure conditions and analyzes risks, HAZOP evaluates the system comprehensively by evaluating operational risks that may occur based on system parameters. According to data released by the Ministry of Land, Infrastructure and Transport, as of December 2021, the length of roads in Korea is 113,405 km, and the repair of guardrails that have expired must be fixed urgently in terms of traffic safety. Replacing all of these guardrails with new ones requires a very large cost, but if the guardrails are repaired with a vehicle equipped with the G-Save method, carbon emissions are reduced, the repair period is shortened, and great economic benefits can be obtained. However, risk assessment for guardrail coating vehicles has not been done so far. Focusing on this point, this study aims to evaluate the risk of these coating vehicles and describe the results. Finally, we found that the Risk Priority Numbers(RPN) in the FMECA risk assessment were greatly reduced, and 6 risk factors from HAZOP risk assessment and actions were taken.