• Journal of the Korean Society of Safety
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• v.21 no.3 s.75
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• pp.137-142
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• 2006

Quantification of error possibility, in an HRA process, should be performed so that the result of the qualitative analysis can be utilized in other areas in conjunction with overall safety estimation results. And also, the quantification is an essential process to analyze the error possibility in detail and to obtain countermeasures for the errors through screening procedures. In previous studies for the quantification of error possibility, nominal values were assigned by the experts' judgements and utilized as corresponding probabilities. The values assigned by experts' experiences and judgements, however, require verifications on their reliability. In this study, the validity of new error possibility values in new MCR design was verified by using the Onisawa's model which utilizes fuzzy linguistic values to estimate human error probabilities. With the model of error probabilities are represented as analyst's estimations and natural language expression instead of numerical values. As results, the experts' estimation values about error probabilities are well agreed to the existing error probability estimation model. Thus, it was concluded that the occurrence probabilities of errors derived from the human error analysis process can be assessed by nominal values suggested in the previous studies. It is also expected that our analysis method can supplement the conventional HRA method because the nominal values are based on the consideration of various influencing factors such as PSFs.

• Environmental Engineering Research
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• v.25 no.3
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• pp.281-289
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• 2020

Environmental fate of ionizable organic pollutants such as perfluoroalkyl acids (PFAAs) are of increasing interest but has not been well understood because of uncertain values for parameters related with atmospheric interphase partitioning behavior. In the present study, not only the values for air-water partition coefficient (K_AW) and dissociation constant (pKa) of PFAAs were induced by adjusting to in situ measurements of air-water distribution coefficient between vapor phase and rainwater but also gas-particle partition coefficients were also estimated using three-phase partitioning model of ionizable organic pollutants, in situ measurements of PFAAs in aerosol and air vapor phase, and obtained parameter values. The pKa values of PFAAs we obtained were close to the minimum values suggested in literature except for perfluorooctane sulfonic acids, and COSMOtherm-modeled K_AW values were assessed to more appropriate among suggested values. When applying parameter values we obtained, it was predicted that air particle-associated fate and transport of PFAAs could be negligible and PFAAs could distribute ubiquitously along the transection from urban to rural region by pH-dependent phase transfer in air. Our study is expected to have some implications in prediction of the environmental redistribution of other ionizable organic compounds.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.10a
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• pp.386-393
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• 1996

The paper describes how a Maximum Length Sequence(MLS) and correlation technique in the form of Hadamard transformation may be applied for the measurement of airborne sound reduction. It is shown that in most cases, the values obtained by the MLS technique will be equal to the expected values obtained by the classical method. However, due to the correlation process involved, the MLS method will be much less sensitive to disturbances from extraneous noise. The described method has been implemented in an RTA acoustic analyser.

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.275-276
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• 2019

The purpose of this study was to assess condylar size in volumetric 3D imaging in patients with class I, class II, class III malocclusions. To evaluate the differences among the three experimental groups, the condylar values of men were analyzed. There was a significant difference in the measured values of height. Among the three experimental groups, the condylar measurements in women showed significant differences in height and width. This study is expected to be used for determining the connection between malocclusion and condyle as a base line data.

• The Korean Nurse
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• v.36 no.3
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• pp.70-80
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• 1997

This study of elderly in-patient subjects' expected level of care given by family members and nurses is intended to provide foundational information for use by nurses is attending to elderly patients. The objects of the study were elderly in-patients over the age of 65 hospitalized at two General hospitals in Chonju: 102 subjects filled out the 60 question survey between December 16 and 24. 1996. The analysis process was conducted using SPSS producing percentage. mean and standard deviation. maximum and minimum values. t-test, ANOVA. and so on. The results are as follows: 1. From the general results of the survey. one can observe that statistically significant differences appeared in various levels of education of the subjects: no education(2.98). primary school completed(2.91). middle school or higher completed(2.77). As shown. the lower level of education correlates with higher care-giving expectation. 2. On a scale of 1(minimum) to 4(maximum). the mean levels of care expected by elderly inpatients from their families is 2.93. with a standard deviation of 0.28. The level of psychological care expected(mean 3.02. standard deviation 0.31) is higher than the level of care expected(mean 2.83. standard deviation 0.34). 3. The level of care expected among those of different levels of dependency for daily living (differentiated as dependent. partially dependent. independent) was highest among the partially dependent(mean 2.98. standard deviation 0.17). but the results were not statistically significant. 4. Elderly in-patients with high levels of emotive interaction with their families expected relatively high levels of physical care. while the highest levels of socio-psychological care were expected from those who reported normal levels of emotive interaction with their families. However. We can see that low levels of care are expected from those reporting low levels of emotive interaction with their families. Overall. the differences in the level of care expected between those reporting different levels of emotive interaction with their families was not shown to be statistically significant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.612-618
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• 2020

In recent years, the demand for external window cleaning has increased, but the process is a very dangerous manpower-dependent operation. In addition, it is difficult to clean at the desired frequency in a business that values cleanliness. Therefore, there is a need to automate this work. This paper presents the concept of a device that can be attached to a specific window and clean the window continuously. The economic feasibility of this device was analyzed. The estimated manufacturing cost of the equipment was approximately 10 million won, but the possible investment cost was at least 9.8 million won for five years of endurance and 103 million won for 10 years of endurance. Therefore, the expected savings well exceed the equipment cost, and it was evaluated as having economic feasibility. Since this study analyzed only quantitative indicators, the expected cost reduction due to a reduction in safety accidents, productivity improvement, construction time reduction, and quality improvement was not considered. Therefore, it is expected that the calculated economic feasibility will be more accurate if the cost reduction effect by the automation equipment is calculated by adding the expected values not considered in this study.

• Journal of Welding and Joining
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• v.5 no.1
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• pp.42-56
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• 1987

Fatigue Fracture behaviors of the TIG-welded aluminum alloys, such as Al 2024-T4, A1 5050-0 and Al 7075-T7 were investigated when a crack propagated from tensile residual stress region and compressive residual stress region. The experimental values were compared with the values expected by the Forman equation. The experimental results are summarized as the following: (1) In case of fatigue crack propagation from residual stress region, the values predicted by Forman equation were Found to exactly corresponded to the experimental values. (2) When the stress intensityfactors affected by compressive residual stress, Kres, were greater than the stress intensity factors by minimum applied stresses. Kmin, the Forman equation was found to be improper to be applied directly, but the equation appeared to be proper, if the stress ratio was modified to zero. (3) The experimental results confirmed that residual stress was relaxed by repeated tensile loading and the relaxing trend was greater in case of compressive residual stress than that of tensile residual stress.

• Journal of Nutrition and Health
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• v.18 no.1
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• pp.46-54
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• 1985

Three types of infant food were experimentally prepared based on the average caloric requirement for, Koreans : Formula A, with 1/3 RDA for 4-6 month, formula B, with 1/2 RDA for 7-9 month, and formula C, with 2/3 RDA for 10-12 month old infants. Into each formula was added approximately 50% of rice. Analysis of the nutritive values on these formula showed no deviance Com the expected values in case of general nutrients while the percent of essential amino acids in protein was muck higher except methionine. Since iron content was found to be below the half of except values, a sufficient amount of iron as required in RDA should be additionally supplied, for example, in iron drops. The infant preference test on each formula showed much favorable acceptability : 50% of them responded as moderate, 33.3% as favorable, 12.5% as disliking, and 4.2% as disgusting. The test also showed no noticeable change in both feces and appetite.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.170-176
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• 2001

An optimization problem to obtain the optimal replacement interval considering the salvage values is studied. The system is minimally repaired at failure and is replaced by new one at age T(periodic replacement policy with minimal repair of Barlow and Hunter〔2〕). Our model assumes that the time horizon associated with the number of replacements is random The total expected cost considering the salvage values with random time horizon is obtained and the optimal replacement interval minimizing the cost is found by numerical methods. Comparisons between non-considered salvage values and this case are made by a numerical example.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.313-315
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• 2001

The power system automation, especially the substation automation is a major issue. so it has been widely studied each country in the world. Since the substation system includes lots of measuring devices. a lot of data and system information are transmitted to operators. The measured values usually have the error that results from the communication process, and it can degrade the reliability of estimated values. So. the detection and correction of measured values at a substation are important factors for substation automation. In this paper, we study the detection and col of measured values at the domestic 154kV/2 distribution substation of double bus structure study will be useful for expected economic dispatch measuring device's inspection and corr management by SCADA system operation, substation automation.