• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.941-944
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• 2000

This paper proposes, for the first time, the design of class I pull-push power amplifier. With the new design, the output power is increased by four times when compared to conventional single-end class I connection amplifier with the same supply voltage. The performance of the proposed amplifier is verified by with a 100-kHz power amplifier constructed using general-purpose NPN transistors.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.1
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• pp.339-363
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• 2023

In response to the changing needs of users and library services, there is a need to develop a library information science curriculum that reflects such change and to foster competent librarians. Recent studies abroad have emphasized the need for librarians who can apply design thinking methods which is a problem-solving methodology that expansively explores various alternatives and derives results, in response to recent changes and problems occurring in libraries. In this study, in order to understand how design thinking methods can be taught and to understand the perceptions of the students and librarians involved in the course, a case study is conducted of a class that applied design thinking methods and students and librarians have been interviewed who had experience participating in the class. By reflecting on the needs of students and librarians', this study explored new directions of what forms courses can take for future librarians. Based on the results of the analysis, among the different characteristics of design thinking, the value of cooperation, problem-solving ability, flexibility and iteration of design characteristics was considered as the value of a class for LIS students and librarians where design thinking methods were applied. From the findings, the research suggests future directions of creating more structured courses that involve an element of design thinking.

• Korean Medical Education Review
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• v.26 no.1
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• pp.55-69
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• 2024

Amid the increasing interest in medical humanities education, this study developed a medical humanities course that utilized design thinking to foster creative thinking, problem-solving, and collaboration skills that pre-medical students should possess. The course's efficacy was assessed by evaluating improvements in core design thinking skills. The present study was conducted among 83 first-year medical students after planning and implementing a design thinking course. The reflection journals written by students along the course of the class were examined using the template analysis technique to evaluate the effectiveness of the class. The study's primary findings showed the successful development of step-by-step medical humanities education content utilizing design thinking and its practical implementation in a class. Moreover, the course improved students' core design thinking skills effectively, and in a balanced way. These results illustrate the effective application of design thinking in medical school through a medical humanities course. These findings indicate that a medical humanities course can help medical students showcase their abilities to collaborate and solve problems in the real world. This paper suggests the need for further research to develop a curriculum that integrates design thinking and investigate the relationship between medical students' core competencies and design thinking-based courses.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.87-90
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• 2005

High-efficiency switched-mode circuits such as the class-E amplifier are well-known in the MHz frequency range. The class-E amplifier is a type of switching mode amplifier offering very high efficiency approaching 100%. In this paper of the class-E amplifier by using pHEMT device, the design has been done theoretically and experimentally, with simulation by using the harmonic balance method using circuit simulator. The amplifier using microstrip circuit and the pHEMT demonstrate 66% power-added- efficiency (PAE) at 2.4GHz with 17.6dBm of output power.

• Journal of Distribution Science
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• v.13 no.6
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• pp.5-10
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• 2015

Purpose - Conspicuous consumption is the public display of wealth to impress others. In this study, consumption patterns by social class and economic development of countries were theoretically examined. Research design, Data, and Methodology - A qualitative approach of historical investigation and literature review was employed to identify current trends and emerging phenomena in the areas of consumer behavior and conspicuous consumption. Result - The main participants of conspicuous consumption have changed from the upper class in developing countries to the middle class in developed countries. While the main purpose of conspicuous consumption, that is, achieving higher status, remains unchanged, a leisure upper class has emerged as a new consumer group for conspicuous consumption in developed countries. Conclusions - To satisfy consumers'demands for new conspicuous consumption, marketers are encouraged to offer luxury experience and hybrid products.

• Journal of electromagnetic engineering and science
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• v.16 no.1
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• pp.52-56
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• 2016

This paper suggests a class-F power amplifier with split open-end stubs to provide a broadband high-efficiency operation. These stubs are designed to have wide bandwidth by splitting wide open-end stubs into narrower stubs connected in shunt in an output matching network for class-F operation. In contrast to conventional wideband class-F designs, which theoretically need a large number of matching lines, this method requires fewer transmission lines, resulting in a compact circuit implementation. In addition, the open-end stubs are designed with slant ends to achieve additional wide bandwidth. To verify the suggested design, a 10-W class-F power amplifier operating at 1.7 GHz was implemented using a commercial GaN transistor. The measurement results showed a peak drain efficiency of 82.1% and 750 MHz of bandwidth for an efficiency higher than 63%. Additionally, the maximum output power was 14.45 W at 1.7 GHz.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1605-1607
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• 2000

In this paper, the design of class AB BiCMOS log-domain filter for low-voltage and low-power was proposed. This filter is consist of a log-domain integrator using folded junctions with capacitor connected to emitter and it's class AB structure. A comparison between the proposed class AB BiCMOS log-domain filter and classical class A BiCMOS log-domain filter is drawn on the basis of SNR, THD and the frequency response. This comparison shows proposed filter are more than good SNR, THD and frequency characteristics than more class A log-domain filter for low voltage and low power.

• Journal of Korean Home Economics Education Association
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• v.13 no.1
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• pp.39-53
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• 2001

The purpose of this study is to develop lesson plan and to evaluate its application for the chapter of 'family life and housing'in the class of Home Economics in the third grade of middle school through the application of the Universal Design. This study has been done in three phases : analysis. development. and evaluation phase. The results of this study were as follows : First. in the development of the concept of the Universal Design. the objective of learning aimed to build the housing and utilities for all family members. Moreover. the various learning materials such as computer program. video materials. and worksheets of the group work were utilized to enhance the effectiveness of the lesson plan. Second. the evaluation of the students was examined through the assessment of the concept of the design. and the degree of class participation of student at the end of class. The LT cooperative learning as an instructional method was perceived to be appropriate and the participation of the cooperative work was also enhanced. The use of the computer programs. and video tapes was considered to be useful. Third. the response of the teachers was found to be both positive and negative. Teachers'positive reactions indicated that the use of the Universal Design facilitated student's participation in class stimulating their motivations and creative ideas not only in the classroom but also in the real life as for the negative reactions. teachers perceived understanding of the concept of the Universal Design. the activities of the students and class hours were relatively shout. These should be added to by the further study with the teachers endeavor.

• Journal of Ocean Engineering and Technology
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• v.32 no.5
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• pp.310-323
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• 2018

In order to protect lives and prevent large-scale injuries in the event of a fire on a ship or an offshore plant, most classification societies are strengthening their fire resistance designs of relevant cargo holds and accommodation compartments to keep flames from being transferred from a fire point to other compartments. Particularly in critical compartments, where flames should not propagate for a certain period of time, such as the A60 class division, both the airtightness and fire-resistant design of a piece passing through a bulkhead are subject to the Safety of Life at Sea Convention (SOLAS) issued by the International Maritime Organization (IMO). In order to verify the suitability of a fire-resistant design for such a penetrating piece, the fire test procedure prescribed by the Maritime Safety Committee (MSC) must be carried out. However, a numerical simulation should first be conducted to minimize the time and cost of the fire resistance test. In this study, transient thermal analyses based on the finite element method were applied to investigate the heat transfer characteristics of a bulkhead penetration piece for the A60 class compartment. In order to determine a rational bulkhead penetration piece design, the transient heat transfer characteristics according to the variation of design parameters such as the diameter, length, and material were reviewed. The verification of the design specification based on a numerical analysis of the transient heat transfer performed in this study will be discussed in the following research paper for the actual fire protection test of the A60 class bulkhead penetration piece.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2099-2101
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• 2005

The problem of observer design for a class of Lipschitz nonlinear systems is considered. We propose a new observer design method which takes into account the structure of perturbed nonlinear terms with a scaling factor ${\epsilon}$. An example is provided to demonstrate the usefulness of our result over the existing method.