• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.6
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• pp.449-456
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• 2009

The RMS(Root Mean Square) current stress reduction technique for the PFC link capacitor is proposed. Although the various parameter is exist for optimizing the link capacitor, the RMS current stress is the most weighty practical parameter. The proposed C-L filter can reduce effectively the RMS current stress by filtering the output current. And with the C-L-L-C filter proposed in this paper, the more RMS current stress can be reduce because it filters not only the output current, like C-L filter, but also the input current of DC/DC stage. The proposed filter is simple to design and have no effect on the control part of the PFC because of the very low crossover frequency. To confirm the validity of proposed filter, theoretical analysis, the design guide, verification of experimental results are presented.

• Applied Chemistry for Engineering
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• v.19 no.6
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• pp.583-591
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• 2008

Recently, as a demand for the portable device is surged, there are needs to develop a new fuel cell system for replacing the conventionally used secondary battery. For this purpose, it becomes important to develop direct formic acid fuel cell (DFAFC) that uses formic acid as a fuel. The formic acid can offer typical advantages such as excellent non-toxicity of the level to be used as food additive, smaller crossover flux through electrolyte, and high reaction capability caused by high theoretical electromotive force (EMF). With the typical merits of formic acid, the efforts for optimizing reaction catalyst and cell design are being made to enhance performance and long term stability of DFAFC. As a result, to date, the DFAFC having the power density of more than $300mW/cm^2$ was developed. In this paper, basic performing theory and configuration of DFAFC are initially introduced and future opportunities of DFAFC including the development of catalyst for the anode electrode and electrolyte, and design for the optimization of cell structure are discussed.

• Journal of Korean Medical Science
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• v.33 no.49
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• pp.314.1-314.15
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• 2018

Background: Despite its growing significance, studies on the burden of disease associated with natural disasters from the perspective of public health were few. This study aimed at estimating the national burden of disease associated with typhoons and torrential rains in Korea. Methods: During the period of 2002-2012, 11 typhoons and five torrential rains were selected. Mortality and morbidities were defined as accentual death, injury and injury-related infection, and mental health. Their incidences were estimated from National Health Insurance Service. Case-crossover design was used to define the disaster-related excess mortality and morbidity. Disability-adjusted life years (DALYs) were directly assessed from excess mortality and morbidity. Results: The burden of disease from typhoons increased with the intensity, with 107.7, 30.6, and 36.6 DALYs per 100,000 per event for strong, moderate, and weak typhoons, respectively. Burden of disease from torrential rains were 56.9, 52.8, and 26.4 DALYs per 100,000 per event for strong, moderate, and weak episodes, respectively. Mental disorders contributed more years lived with disability (YLDs) than did injuries in most cases, but the injury-induced YLDs associated with strong typhoon and torrential rain were higher than those of lower-intensity. The elderly was the most vulnerable to most types of disaster and storm intensities, and males younger than 65 years were more vulnerable to a strong torrential rain event. Conclusion: The intensity of torrential rain or typhoon was the strongest determinant of the burden of disease from natural disasters in Korea. Population vulnerable may vary depending on the nature and strength of the disasters.

• Journal of the Korea Society of Computer and Information
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• v.24 no.11
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• pp.179-185
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• 2019

In this paper, We purpose the basic data for the success of effective CPR using mirror in order to increase the quality of chest compression during CPR. The subject of this study was an experimental study based on a randomized crossover design of 28 people who completed the BLS Health Care Provider, and collected data were analyzed by SPSS Ver. 23.0 for Win statistics program. As the research methods, depth, speed, compression to relaxation ratio, arm angle and easiness during the chest compression were measured. Taken together, the results of this study showed that using a mirror-based chest compression method for chest compressions in adult CPR could make chest compressions easier, in addition, the quality of breast compression was improved by improving the posture of the rescuers, such as the average depth of compression, compression to relaxation ratio, and arm angle. However, it is necessary to confirm the feasibility of clinical application through additional studies on various environmental factors and job groups for mirror-based chest compression method.

• Journal of the Korea Society of Computer and Information
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• v.25 no.12
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• pp.227-233
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• 2020

The purpose of this study is to compare the speed, confidence, and ease of endotracheal intubation in a difficult posture by using the SALT(Supraglottic Airway Laryngopharyngeal Tube), and a direct laryngoscope to improve the ability to implement professional airway management. The subject of the study was an experimental study by a randomized crossover design, targeting 30 first-class emergency medical technicians working in J-do fire station, and the SPSS 20.0 version was used for data analysis. The endotracheal intubation by using SALT showed a significant difference in speed compared to endotracheal intubation by using a direct laryngoscope(p<.001), and also showed a significant difference in confidence and ease(p<.001). If it is difficult to endotracheal intubation by direct laryngoscope, or in the case of trauma patients, if SALT is used, safe and rapid intubation will be possible. In addition, to improve the efficiency of professional airway management, it is believed that the introduction of SALT in domestic sites is necessary.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.9
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• pp.1392-1398
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• 2022

This study was conducted for effective CPR by comparing the quality of chest compressions when using a new chest compression method during pediatric CPR. As an experimental study by Randomized Crossover Design, the depth, speed, compression-to-relaxation ratio, ease, and stability were measured when performing chest compressions for 28 Emergency Medical Technicians who completed the BLS Health Care-Provider qualification. The collected data were analyzed by using the SPSS Ver. 23.0 for Win statistical program. To summarize the results of this study, if the new chest compression method was used for chest compression in pediatric CPR, the qualitative indicators of chest compressions were improved. It is good to stick to the existing method, but through the new chest compression method, it will be necessary to confirm the possibility of clinical use based on additional research on various age groups and environmental factors.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.300-302
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• 2022

The purpose of this study is to compare the speed, confidence, and ease of endotracheal intubation in a transfer posture by using the SALT(Supraglottic Airway Laryngopharyngeal Tube), and a direct laryngoscope to improve the ability to implement professional airway management. The subject of the study was an experimental study by a randomized crossover design, targeting 28 first-class emergency medical technicians working in J-do fire station, and the SPSS 20.0 version was used for data analysis. The endotracheal intubation by using SALT showed a significant difference in speed compared to endotracheal intubation by using a direct laryngoscope(p<.001), and also showed a significant difference in confidence and ease(p<.001). If it is transfer to endotracheal intubation by direct laryngoscope, or in the case of transfer patients, if SALT is used, safe and rapid intubation will be possible.

• Korean Journal of Computational Design and Engineering
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• v.18 no.2
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• pp.129-137
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• 2013

This paper proposed the scheduling method for tire mixing processes using the genetic algorithm. The characteristics of tire mixing process have the manufacturing routing, operation machine and operation time by compound types. Therefore, the production scheduling has to consider characteristics of the tire mixing process. For the reflection of the characteristics, we reviewed tire mixing processes. Also, this paper introduces the genetic algorithm using the crossover and elitist preserving selection strategy. Fitness is measured by the makespan. The proposed genetic algorithm has been implemented and tested with two examples. Experimental results showed that the proposed algorithm is superior to conventional heuristic algorithm.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.495-503
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• 2011

When a patent of an innovative (brand-name) small-molecule drug expires, generic copies of the innovative drug may be marketed if their therapeutic equivalence to the innovative drug has been shown. The small-molecule drugs are considered therapeutically equivalent and can be used interchangeably if two drugs are shown to be pharmaceutically equivalent with identical active substance and bioequivalent with comparable pharmacokinetics in a crossover clinical trial. However, the therapeutic equivalence paradigm cannot be applied to biosimilars since the active ingredients of biosimilars are huge molecules with complex and heterogeneous structures, and these molecules are difficult to replicate in every detail. The European Medicine Agency(EMEA) has introduced a regulatory biosimilar pathway which mandates clinical trials to show therapeutic equivalence. In this paper, we discuss statistical considerations in the design and analysis of biosimilar cancer clinical trials.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.2
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• pp.2060-2064
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• 2020

Background: Recently, the kinesiology taping (KT) method was reported to be effective in improving walking ability in foot drop patients after stroke, but the clinical basis is still unclear. Objectives: The KT method was compared with ankle-foot orthotics (AFO) to investigate gait ability in foot drop patients after stroke. Design: Crossover study design. Methods: In this study, 11 stroke patients with foot drop participated. Walking ability of all subjects for both conditions (KT and AFO) was measured using the GAITRite system. The order of application of the two conditions was determined randomly by drawing lots. Wilcoxon signed-rank test was used to compare walking ability between the two conditions. The level of statistical significance was set at P<.05. Results: There were no significant differences between the KT and AFO methods in terms of velocity, cadence, step length, and stride length (P>.05, all). Conclusion: This study recommends KT as an alternative to the AFO, since KT provides evidence of preventing of foot drops and improving gait ability in stroke patient.