• Journal of Aerospace System Engineering
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• v.16 no.6
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• pp.35-44
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• 2022

This study aims to evaluate the stress and life of cylindrical roller bearings used in aircraft gearboxes, and to select a roller profile that minimises the contact stress between bearing rollers and raceways. The mounting clearance of four points contact ball bearing was determined, so that cylindrical roller bearings support all radial loads, and the bearing mounting position was determined to maximise the bearing lives. In addition, the static safety factor and dynamic life of bearing were predicted according to ISO 76 & ISO/TS 16281 using the load spectrum determined based on the operating load cases of aircraft gearboxes. Furthermore, the optimal roller profile was selected by analysing the contact stress according to the roller profile shape, and the safety of each roller was evaluated. The results stated that the required safety factor and lifetime were satisfied, and Johns Gohar roller profile was optimal.

• Journal of Korean Association for Spatial Structures
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• v.18 no.2
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• pp.87-97
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• 2018

Stone pagoda structures have continued to be aged due to the combination of various damage factors. However, some studies on nonstructural damage have been carried out, but assessment studies on structural damage have not been done in various ways. Therefore, in this study, structural and nonstructural influencing factors according to the damage types are classified and the damage assessment according to the structural influencing factors affecting the behavior of the stone pagoda structure is performed. In addition, the damage rating classification criteria for each type of structural damages or damage locations are presented, and the damage index is calculated by providing the criteria for the classification of damage according to the degree of damage to which the damage is caused. Therefore, this study can evaluate quantitatively the damage status of stone pagoda structures.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.213-218
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• 2019

In this study, a high-temperature vulcanizing (HTV) method was used to achieve a shore a hardness of 70. The basic base was composed of 60% silicon gum (GUM) which is a high-viscosity polymer, 30% fumed silica (FS), and 5% of plasticizer. The GUM and FS were mixed well with less than 1% silane to improve rubber strength. Expanded vermiculite was added as a filler at 10%, 15%, and 20%. The curing conditions were $170^{\circ}C$ for 10 min and a molding method was applied. We report herein, the results of inorganic analysis and flame-retardant and tracking tests on the expanded vermiculite. The flame retardance and tracking test outcomes for a shore a hardness of 70 were found to be optimal when the expanded vermiculite content was 10%.

• Journal of Korean Critical Care Nursing
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• v.10 no.3
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• pp.41-52
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• 2017

Purpose : This concept analysis identified attributes and defined triage competency among emergency nurses. Method : Walker and Avant's approach was used to guide the concept analysis. A literature review was completed including 26 studies, 5 reports of related associations, and 5 books. Results : The concept of triage competency in emergency nurses was identified as five attributes: clinical judgment, expert assessment, management of medical resources, timely decision, and communication. Antecedents of the concept were triage education and emergency room experience. The consequences of the concept were efficiency of care, patient rating, and safety. Triage competency in emergency nurses was defined as the comprehensive ability to prioritize patients' urgency and allocate limited medical resources. Conclusion : This study is meaningful since it clarified triage competency among emergency nurses. The attributes and empirical indicators of this study will likely lay the foundation for development of triage competency metrics.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.188-191
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• 2004

We experimented variables of four kinds(a/d=1.5, 2.5, 3.5, 4.5) of shear span ratio to consider a structural characteristic of high-strength lightweight concrete beam used industrial by-product. Through the research of serials, the more increase of shear span ratio, the more ductility is superior. Rating the capacity of high-strength concrete beam and the capacity of lightweight concrete beam, in existing lightweight concrete beam evaluation formula, if a shear strength formula for normal concrete multiplies 0.85(reduction factor), it is rated as safety side over shear span ratio 2.5, but it is riskful at low shear span ratio. Therefore it is important that these factors are considered as the evaluation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.4
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• pp.140-145
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• 2015

In the present study, the structural safety of the bolt portion and collet tool structure of the pipe-fitting tool is analyzed by using the finite element technique. Two forces as piston forces with the magnitude of 187.5 Tons are applied to the inner and outer portions of the collet tool, respectively. A structural load of 750 Tons is applied to the bolt portion. In the analysis results, it is found that the structure becomes safe under the current loading conditions. The reliability rating of the pipe is calculated in this study. The material properties of the actual material are evaluated by using mechanical testing. Therefore, the material properties are used to carry out static structural and optimization analysis.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.313-321
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• 1996

Our laboratoy has been participated in Proficiency Analytical Testing (PAT) program which is operated by the Americal Industrial Hygiene Association in cooperation with the National Institute for Occupational Safety and Health (NIOSH). The program is designed to assist a laboratory improve its analytical performance by providing samples on a quarterly basis, evaluating the results, and providing reports on how well the laboratory performed. Evaluation of the results reported here covers five rounds of the PAT program (round 121~round 125). The way a laboratory is evaluated by PAT program is as follows: 1) There is no overall proficiency rating given to a laboratory. 2) A proficiency rating is given for each type of analyze (i.e., metals, silica, asbestos, solvents) that a laboratory analyzed. 3) Proficiency is rated acceptable ("A") if Z score lies between -3 and +3, and unacceptable if Z score is either higher than +3 ("H") or lower than -3 ("Lo"). Z score = (reported data - reference value) / standard deviation 4) For a laboratory to be rated proficient it must either have had no outliers over the most recent two rounds or of the samples actually analyzed over the past year (past four rounds), 75 % or more of the analyze sample results must be acceptable. According to the above rating criteria of PAT program, performance of metals including cadmium, lead, chromium and zinc, and asbestos sample analyses were rated acceptable ("A"). For silica analyses, all samples except one out of four samples in round 122 was rated high("H") were acceptable showing 95 % of ing 95 % of acceptance rate (19/20) throughout the rounds. Analyses of organic solvents were done on 52 samples in 9 types including methanol(MOH), 1,1,1-trichloroethane(MCM), tetrachloroethylene(PCE), trichloroethylene(TCE), benzene(BNZ), o-xylene(OXY), toluene(TOL), chloroform(CFM), 1,2-dichloroethane(DCE). All samples analyzed were rated acceptable except 2 samples that were rated high; one out of each four MCM and TCE samples in round 121, and one that was low out of four o-xylene analyses in round 122 indicating 94 % of acceptance rate(49/52) throughout the rounds. According to the laboratory rating criteria, our laboratory is rated proficient so far for all types of contaminants.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.8
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• pp.3636-3643
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• 2011

To prevent the electrical accidents in the laboratory, we identify problems for periodic inspections of the electric field and develop a fuzzy inference system that can be practically applied to check items. Focusing on electrical safety in the lab environment, we draw check items that can be applied in common and develop a standard checklist that is consistent with the laboratory electrical safety and the periodic inspections. Using the standard checklist we select the items that may contain a linguistic ambiguity and define the membership functions for these items. We also have a safety rating defined by the membership function. Using these fuzzy variables we form the fuzzy rules in the form of 'If-Then' and develop a fuzzy inference system through the fuzzy engine. From this, electrical accidents could be prevented in advance continuously by managing the intelligent and efficient inspection and electrical safety to prevent the electrical accidents in the laboratory.

• Archives of Plastic Surgery
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• v.42 no.6
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• pp.721-728
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• 2015

Background We conducted this clinical study to compare the efficacy and safety between Neuramis Deep and Restylane in the correction of nasolabial folds. Methods In this phase III, randomized, multi-center, double-masked, matched-pairs, active-controlled trial (ClinicalTrials.gov Identifier: NCT01585220), we evaluated a total of 67 subjects (n=67). All the subjects underwent Neuramis Deep treatment on one side and Restylane on the contralateral side of the bilateral nasolabial folds at a ratio of 1:1. To compare the efficacy of Neuramis Deep and Restylane, we evaluated the Wrinkle Severity Rating Scale scores and those of the Global Aesthetic Improvement Scale. In addition, we compared the safety of Neuramis Deep and Restylane based on adverse events, physical examination, and clinical laboratory tests. Results Neuramis Deep was not inferior in improving the nasolabial folds as compared with Restylane. In addition, there was no significant difference in the efficacy between Neuramis Deep and Restylane. There were no significant differences in safety parameters between Neuramis Deep and Restylane. Conclusions In conclusion, our results indicate that Neuramis Deep may be a safe, effective material for improving the nasolabial folds. However, further studies are warranted to compare the tolerability of Neuramis Deep and Restylane based on histopathologic findings.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.89-101
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• 2022

The study was conducted in Erhe Park, a neighborhood park in Dali City, China, to derive the influence of environmental factors in the park on the elderly's satisfaction and to analyze the satisfaction in order to provide improvement recommendations. First, the evaluation indicators were selected, by referencing previous research into the elderly's evaluation of external spatial environments and the influence of various factors was determined from the questionnaire and factor analysis. Second, a fuzzy comprehensive evaluation was conducted to understand the satisfaction of the elderly, and then an Importance-Performance Analysis(IPA) analysis was conducted to develop improvement recommendations. Results of the factor analysis showed that park's environmental factors were grouped into four categories: facility suitability and comfort, safety and convenience of use, natural environment comfort, and parkway convenience. Based on this, the overall satisfaction rating for the environmental factors in Erhe Park was between satisfactory and average. The natural environment comfort was rated satisfactory, the facility suitability and comfort, and convenience and safety were rated average, and parkway convenience was rated near to satisfaction. The IPA analysis revealed that the suitability of rest facilities, suitability of convenience facilities, facility management status, safety of entrances and exits, and nighttime lighting facilities were items of high importance but low satisfaction that needed to be improved. The results of this study can be utilized as a guide for future building or readjustment of senior-friendly parks, and they are critical for increasing senior-friendly park satisfaction.