• 대한전자공학회논문지SD
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• 제37권10호
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• pp.17-24
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• 2000

면적 효율이 높은 대칭 구조를 갖는 이중층 나선형 인덕터를 제시하였으며 그 특성을 일반적인 단일층 나선형 인덕터와 비교하여 분석하였다. 일반적인 예측과 달리 이중층 인덕터의 상하층 유도 계수가 인덕터의 권선수와 함께 증가하는 것을 확인하였고 이로 인하여 동일한 면적에 대하여 이중층 인덕터은 권선수에 따라 단일층에 비해 2.5-4배 정도 높은 인덕턴스값을 나타내었다. 또한 같은 인덕턴스 값에 대하여 이중층 구조로 단일층 구조 보다 높은 충실도를 가짐을 확인하였다. 본 논문에서는 이중층 나선형 인덕터가 단일층 나선형 인덕터보다 면적 효율과 충실도 측면에서 우수하여 RF집적회로에 활용되기에 적절한 보다 구조임을 제시하고자 한다. 제시된 이중층 나선형 인덕터는 완벽한 대칭 구조를 갖도록 설계되었으며 측정 결과에서 이와 같은 특성을 확인할 수 있었으며, 고주파용 초크로서 활용가능성을 확인하였다.

• 대한물리의학회지
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• 제15권3호
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• pp.99-108
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• 2020

PURPOSE: This study examined the effects of the confusion level in performing dual tasks using smartphones while walking in subjects with chronic ankle instability (CAI). METHODS: Twenty subjects with CAI and 20 healthy subjects participated in the study. The spatial, temporal, spatial-temporal, and variability gait parameters were measured using GAITRite under four different conditions: general gait, web surfing during gait, texting during gait, and gaming during gait. Two-way repeated-measures analysis of variance was used to analyze the interaction according to the group (2) and confusion level in dual-tasks (4). One-way repeated-measures analysis of variance was used to compare the changes within the group according to the confusion level in dual-tasks. The changes between groups were compared using an independent t-test. The statistical significance level was set to p = .05. RESULTS: Significant interactions in the temporal and spatial-temporal gait parameters were found between the dual-task conditions and the other groups (p < .05). Significant within-group differences in the spatial, temporal, and spatial-temporal gait parameters were found according to the confusion level in dual tasks (p < .05). Significant between-group differences were observed in the temporal and spatial-temporal gait parameters according to the confusion level in dual tasks (p < .05). CONCLUSION: The effect of the confusion level in dual tasks was greater in subjects with CAI than in healthy individuals. This study suggests that to prevent reinjury to the ankle, subjects with CAI should avoid dual tasks such as using smartphones while walking.

• 대한가정학회지
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• 제43권10호
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• pp.55-68
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• 2005

This research focused on the family stress, coping strategy, and job satisfaction in dual-earner couples. The subjects of this study were 150 dual-earner couples,300 people, in the Kyeongnam Area, Korea. The major findings from the study are as follows; 1) The degree of family stress of the husband and wife in dual-earner couples was 2.74 and 2.98, respectively, on a scale of 0-5.0. The most stressful event arose from their role as parents caring for their children. The significant variables were religion and the type of expended family in dual-earner couples' husband, and the age of the first child, job, economic level, conjugal period, and marital satisfaction in dual-earner couples' wife. 2) The coping strategy of family stress of the husband and wife in dual-earner couples was 3.41 and 3.45, respectively, on a scale of 0-5.0. Among the strategies, the 'cognitive restructuring' scored highest. The significant variables were religion, the degree of educational level, job, marital satisfaction, and self-esteem in dual-eamer couples' husband, and economic level, the type of expended family, marital satisfaction, and selfesteem in dual-earner couples' wife. 3) The degree of job satisfaction of the husband and wife in dual-earner couples was 3.72 and 3.89, respectively, on a scale of 0-5.0. The most effective variables of job satisfaction of the husband and wife in dual-earner couples was self-esteem and cognitive restructuring strategy, respectively.

• Journal of Power Electronics
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• 제16권1호
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• pp.133-141
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• 2016

This paper focuses on the development of a Five-Level Flying-Capacitor Dual Buck Inverter (FLFCDBI) based on the main circuit of dual buck inverters. This topology has been described as not having any shoot-through problems, no body-diode reverse recovery problems and the half-cycle work mode found in the traditional Multi-Level Flying-Capacitor Inverter (MLFCI). It has been shown that the flying-capacitor voltages of this inverter can be regulated by the redundant state selection within one pole. The voltage balance of the flying-capacitors can be achieved by charging or discharging in the positive (negative) half cycles by choosing the proper logical algorithms. This system has a simple structure but demonstrates improved performance and reliability. The validity of this inverter is conformed through computer-aided simulation and experimental investigations.

• Asia pacific journal of information systems
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• 제14권2호
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• pp.37-59
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• 2004

Team decision making is a collective behavior that needs to be understood by considering properties belonging to team and individual member domains together. This paper introduces a conceptual model called "Dual-Level(DL)" model that describes a team decision-making process in terms of team level, member level, and the relationship between them. The team-level view explains the decision-making process by considering the team as a wholeand divides the process into three stages: Problem Conceptualization, Alternative Generation, and Selection. The member-level view describes what happens to individual members when they go through the group process and splits it into the five phases: Individual Cognitive Mapping, Problem Decomposition, Subproblem Session, Subproblem Integration, and Team Decision. The DL model works as a theoretical framework to explore team decision making by using a set of computational models of team design and team members. In practice, the conceptual framework is used to build a computational model of decision making team, called "Team-Soar."

• 대한통합의학회지
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• 제8권4호
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• pp.107-115
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• 2020

Purpose: This study aims to systematically review the dual-task evaluation applied to the screening of mild cognitive impairment. It also aims to present various evaluation items and results analysis methods for dual tasks applied to patients with mild cognitive impairment. Methods: We conducted a systematic search of published studies in PubMed databases and KISS from January 2000 to August 2020 using the main keywords such as "Dual task," "Mild Cognitive impairment," "Elderly," and "Screening." We selected a total of 10 studies for the analysis from 1314 searched articles. Results: We analyzed the qualitative level of 10 studies that were nonrandomized two-group studies with evidence level II (100.0%). These results suggest that the evidence level of the studies was high. We analyzed 10 studies and identified 12 motor tasks and 19 cognitive tasks. Walking was the most commonly used evaluation motor task and counting backward by ones and naming animals were the most commonly used evaluation cognitive tasks. Moreover, the velocity speed was the most used result analysis method. The results indicate that there were significant differences in dual-task performance between patients with normal and mild cognitive impairment. Conclusion: The results of this study can be used as a basis for the selection of dual-task evaluation items and methods of analyzing the results for screening mild cognitive impairment. Furthermore, they are expected to be used for research on the development of dual-task evaluation tools. It is necessary to compare and analyze the usage trends of dual-task evaluation by cultural differences in future studies.

• PNF and Movement
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• 제7권4호
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• pp.31-36
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• 2009

Many daily activities require people to complete a motor task while walking. Substantial gait decrements during simultaneous attention to a variety of cognitive tasks have been shown by a group of severely injured neurological patients of mixed etiology. And previous studies have shown that the attentional load of a walking-associated task increased with its level of difficulty. The purpose of this study was to analyze subjects' gait changes are affected by the effects of arithmetic task difficulty and performance level. Participants performed a walking task alone, three different Arithmetic tasks while seated, and among them, two kinds of the simillar Arithmetic tasks in combination with walking. Reaction time and accuracy were recorded for two of the Arithmetic tasks. The mean values of the gait were measured using a Timed Up and Go test among 11 with post-stroke patients while walking with and without forward counting (WFC) and backward counting(WBC).There was significant Arithmetic Task Difficulty level between the 10-forward counting task condition(FC) and the 10-backward counting task condition(BC)(p=0.008). The mean values of T.U.G time were significantly higher under backward counting dual-task condition than during a simple walking task(p=0.009) and WFC(p=0.009). The change in T.U.G time during WFC was higher when compared with the change during a simple walking, but there was no significant difference (p=0.246). This study suggesting that a high interference could be linked with a high level of difficulty, whereas adaptive task enabled participants to perfectly share their attention between two concurrent tasks. Future research should determine whether dual task training can reduce gait decrements in dual task situations in people after stroke. And the dual-task-based exercise program is feasible and beneficial for improving walking ability in subjects with stroke.

• 전력전자학회논문지
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• 제22권2호
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• pp.150-158
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• 2017

This study proposes a new pulse-width modulation switching pattern for the low conduction loss of a three-level neutral point clamped (NPC)-based dual-active bridge (DAB) converter. The operational principle for a bidirectional power conversion is a phase-shift modulation. The conventional switching method of the three-level NPC-based DAB converter shows a symmetric switching pattern. This method has a disadvantage of high root-mean-square (RMS) value of the coupling inductor current, which leads to high conduction loss. The proposed switching method shows an asymmetrical pattern, which can reduce the RMS value of the inductor current with lower conduction loss than that of the conventional method. The performance of the proposed asymmetrical switching method is theoretically analyzed and practically verified using simulation and experiment.

• Journal of Power Electronics
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• 제14권6호
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• pp.1189-1196
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• 2014

A modular multilevel-clamped composited multilevel converter ($M-MC^2$) is proposed. $M-MC^2$ enables topology reconfiguration, power device reuse, and composited clamping. An advanced five-level converter ($5L-M-MC^2$) is derived from the concept of $M-MC^2$. $5L-M-MC^2$ integrates dual three-level T-type modules and one three-level neutral point clamped module. This converter can also integrate dual three-level T-type modules and one passive diode module by utilizing the device reuse scheme. The operation principle and SPWM modulation are discussed to highlight converter performance. The proposed $M-MC^2$ is comprehensively compared with state-of-the-art five-level converters. Finally, simulations and experimental results are presented to validate the effectiveness of the main contributions of this study.

• 대한가정학회지
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• 제32권4호
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• pp.97-116
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• 1994

The purpose of the stud is to present an model of the distress process for dual-earner couples. For the data set 340 husbands and wives in dual-earner families living in Pusan were chosen. The questionnaire was composed of Family Stressor Scale Family Resources Scale, Distress Scale. The data were analyzed with the SPSS statistical pacakage using t-test the one-rather than husband. And cothestion, adaptability and the level of stress recognition are important factors affecting the level of physical and psychological distress directly.