• Particle and aerosol research
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• v.7 no.3
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• pp.87-97
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• 2011

In this study, we organized the test results obtained from the performance tests for the CA certificated air cleaners which had been commercially available in Korea since 2003, and analyzed the correlation among the test parameters such as flow rate, particle collection efficiency, clean air delivery rate (CADR), ozone emission, odor removal efficiency and noise level etc. The noise level of 267 air cleaners were increased as concentrated at the 45, 50, 55 dB, which are the required noise level for CA certification according to flow rate, and ozone emissions from the CA air cleaners were significantly lower than the requirement limit, 50 ppb for 24 hour operation. The average particle collection efficiency and odor removal efficiency were 89.3 and 80.8%, approximately 20% higher than the requirement of CA certification, regardless of flow rates. The particle removal performance of an air cleaner was clearly discriminated by its CADR, and the CADR was obtained with a simple calculation: 0.79 x flow rate. The low differentiation of gas removal performance of air cleaners by the current CA gas test method was improved by 3.2, 751.3, 13.4 times for ammonia, acetic acid, respectively, by adopting the CADR concept and the real time measurement method, FTIR, for gas removal performance test.

• Journal of Science Education
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• v.37 no.2
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• pp.348-358
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• 2013

The purpose of this study is to develop the science item on computer-based performance assessment which is able to replace the assessment with actual experimental apparatus. The survey on the necessities and the difficulties of the assessment with actual experimental apparatus was conducted with 57 physics teachers. By reflecting the results of the survey, the computer-based assessment items which are related with constructing circuits with an ammeter and a voltmeter were developed. The developed computer-based assessment items were organized in similarity to assessment conducted with actual experimental apparatus, proper feedback was provided by students' performance in the process of assessment so as to grading performance results automatically. To achieve them, the algorithm was developed so that computer can judge the accuracy of students' performance results.

• The Korean Journal of Emergency Medical Services
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• v.28 no.1
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• pp.47-62
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• 2024

Purpose: This study aimed to provide basic data for infection control education plans based on infection control awareness and performance of paramedic students during clinical field training. Methods: Data were collected from paramedic students with experience in clinical field training. The data collection period was from May 4, 2023, to June 4, 2023, and 132 copies of the collected survey were analyzed using the SPSS27.0 program. Results: Infection control awareness and performance were 4.80±0.24 points and 4.49±0.55 points out of 5, respectively. The infection control awareness of the participants according to clinical field training-related characteristics differed significantly in university education before clinical field training (t=2.100, p=.038). In addition, there were significant differences in performance in the number of clinical field training sessions (F=9.149, p=.000), hospital education before clinical field training (t=5.365, p=.000), and hospital education during clinical field training (t=3.094, p=.002). Conclusion: Before clinical field training, schools should provide infection control education that combines theory and practice suitable for hospital practice so that students can complete the infection control education organized by the hospital. Furthermore, if a university develops infection control in the clinical field training guidelines, it will have a positive impact on students' infection control performance through prior education.

• Journal of Korea Port Economic Association
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• v.30 no.2
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• pp.93-112
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• 2014

To study the business performance, this research reviewed the revenue of 2012 for shipping and logistics companies in Korea, then selected 10 shipping companies and 10 logistics companies according to annual sales amount. These 20 companies are divided into four groups considering their business structure and their financial performance are organized from 2005 to 2012. Then CCR, BCC model has been applied to static efficiency and dynamic changes in productivity for analysis. As an overall result, logistics companies are proven to be better than shipping company in efficiency, change of productivity, growth and profitability. Among the logistics companies, the performance of second party logistics companies are relatively better in those factor above than the third party logistics companies.

• Journal of the Korea Society of Computer and Information
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• v.20 no.2
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• pp.169-180
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• 2015

This study looked into these companies and organizations that were working with the knowledge management system in order to verify how practically such introduction of the knowledge management system would affect the organizational performances. The purpose of this study is to present the strategic guidelines should to consider the introduction of the knowledge management system operated by the organization to analyze how factors affect the performance of the introduction of knowledge management systems are organized in empirical. According to the results, the sub-variables of the management factors such as learning organization, evaluation and reward system, organizational trust and knowledge-sharing activity had all the significant effects on the organizational performance, and of the sub-variables of the information technology factors, the information technology-based structure presented statistically significant results which confirmed that the structure itself also had an influence on the organizational performance. However, the study learned that both the information technology maturity and the system structural excellence had nothing to do with the organizational performance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.6
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• pp.379-383
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• 2015

Some insulating materials are organized and analyzed with variables to obtain the optimized profile of encapsulated three phase of epoxy barrier which is applied to gas compartment and supporting conductors for high voltage GIS (gas insulated switchgear). The high voltage GIS is used in electrical power system and operating reliability. In this paper, optimization possibility of barrier shape including both electrical insulation performance and mechanical strength, premised on that condition minimizing volume and light weight should be kept for high voltage GIS, could be achieved by analysis simulation. As a result, filling material which is lower permittivity such as $SiO_2$ instead of $Al_2O_3$ properly to the epoxy material, can be improved to increase the electrical insulation performance and mechanical strength for an optimized profile barrier of a high voltage GIS.

• Tribology and Lubricants
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• v.28 no.2
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• pp.81-92
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• 2012

To product multi-grade oil like engine oil, a sort of mineral base oil is mixed with a fundamental additive liquid package and a polymer liquid as viscosity index improver in order to improve the lubricating property of oil. That is, engine oil is the mixture of more than two fluids. In this paper, it will be systematically organized the governing equation describing non-Newtonian thermo-hydrodynamic lubrication related with the mixture of incompressible fluids based on the principle of continuum mechanics. Then, in order to find how the thermal analysis effect on the bearing performance lubricated with the mixture of multi-fluids, it will be compared to the performances between the mixture of each liquid to be blended and multi-grade engine oil as a single fluid in a high speed journal bearing. It is found that, in the case of lower viscosity oil, the difference of pressure distribution between the above two cases turns out to be existed, even if the load capacity is same level.

• Journal of Korean Academy of Nursing
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• v.38 no.1
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• pp.83-91
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• 2008

Purpose: The purpose of this study was to test the validity of a modified clinical performance examination (CPX) for preclinical students in nursing. Method: 70 nursing students in their second semester of the junior year at C University participated in CPX. Scenarios and checklists were developed by our research team from September to October 2005. Six stations were organized. Evaluation included physical examination of a patient with lung cancer, education on usage of a metered dosage inhaler, and lobectomy postoperative care. Students were randomly assigned to a station. Result: There was a difference in the CPX scores according to stations. The agreement of scoring between trained faculty members and SPs was more than moderate (r=.647). The correlation between the CPX score and the average grade in the previous semester and between the CPX score and the average grade of a paper and pen test of the pulmonary system of adults was low (r=.276; r=.048). Conclusion: Traditional CPX is generally recommended, however, modified CPX is appropriate for preclinical students in the current Korean Nursing school setting if there are additional scoring systems to balance the testing level at each station.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.1
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• pp.108-114
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• 2011

Steam reformer was organized with steam reforming process and CO removing process. The steam reforming process needed high temperature, 600~900 $^{\circ}C$, for catalytic-reaction which was extract of hydrogen from steam and hydrocarbon. The effects of the evaporator configuration on its heat transfer characteristics were investigated both experimentally and numerically to pursue the miniaturization. In this study, three configurations were considered where the different structures were tested; empty, embossing and mesh filled. For the comparison of heat transfer performance of shape evaporator disk, numerical analysis using SC-Tetra code and experiment were carried out. In case of reformer system design, it should be considered heat transfer rate, differential pressure and fluid flow direction.

• Structural Engineering and Mechanics
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• v.50 no.4
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• pp.459-469
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• 2014

One of the most important structural components of steel structures is the column-base connections which are obliged to transfer horizontal and vertical loads safely to the reinforced concrete (RC) or concrete base. The column-base connections of steel or composite steel structures can be organized both moment resistant and non-moment resistant leading to different connection styles. Some of these connection styles are ordinary bolded systems, socket systems and embedded systems. The structures are frequently exposed to cycling lateral loading effects causing fatal damages on connections like columns-to-beams or columns-to-base. In this paper, connection of steel column with RC base was investigated analytically and experimentally. In the experiments, bolded connections, socket and embedded connection systems are taken into consideration by applying cyclic lateral loads. Performance curves for each connection were obtained according to experimental and analytical studies conducted and inelastic behavior of connections was evaluated accordingly. The cyclic lateral performance of the connection style of embedding the steel column into the reinforced concrete base and strengthening of steel column in upper level of base connection was found to be higher and effective than other connection systems. Also, all relevant test results were discussed.