• The Journal of the Acoustical Society of Korea
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• v.15 no.6
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• pp.52-58
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• 1996

Using the acoustic resonances and oscillatory pulsations considered as the branch of wave technologies, the concept of the acoustic resonance diffusers for waste water treatment which maximize the oxygen transfer efficiency in gas-liquid two phase medium have been proposed, and studies for the principles and performance tests were accomplished. Besides, the design concepts for the low pressure Helmholtz resonator, cylinder and annular type reflection resonator and combined type resonance system have been implemented. The acoustic resonance energy which can speed up the mass transfer process increase the oxygen transfer efficiency, and periodic pulsations generated from the instability of air jet from nozzle make very small air bubbles. Then, the annular type jet resonator(AJR) applying these two principles successfully was evalulated as the most promising device and also the efficiency showing $20{\sim}30%$ better than conventional diffusers has been verified experimentally.

• Architectural research
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• v.18 no.1
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• pp.1-12
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• 2016

This thesis explores Vitruvius and his impact upon other Renaissance architects who compare a city to a building or a building to a city, who match the city and the building into a human body, and who develop their own works. The objective of this study is to furnish an interpretation of their theory and practice through their literature and designs. In this point of view, this article takes notice of Vitruvius's six concepts coined from venustas and divides them into two parts: i.e. aesthetic quality (ordinatio, dispositio, and distributio) and technical activity (eurythmia, symmetria, and $d{\acute{e}}cor$) each. This thesis indicates that Vitruvius's successive impacts from the concepts bring about concrete design principles through proportional measurements, placing together, and hierarchic values for the former, as well as appropriate use through beautiful look, symmetrical harmony, and appropriate uses for the latter, tracking notions between a city as a house and vice versa, and either the ideas of the house or the city in the synthesis of the human body, which follows the perfect number and module based on the human body. The thesis shows that the representations of architecture and the city take place with the form of a circle and a square that express the religious belief and the cosmos, substantiating the connection between the proportions of the human body and numbers, and ultimately satisfying a concept of centrality, which is slowly extended to the enclosed plaza at the urban level from chambers, atrium, and corridors at the residence level.

• Journal of Digital Contents Society
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• v.8 no.2
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• pp.235-243
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• 2007

Students develop mathematical concepts through concrete operations in the area of mathematics. However, most of the learning contents provided on the web are not interactive and limit interactions with learners. To overcome the limitations, there have been needs to develop learning contents to support active interactions with students according to their cognitive levels. In this study, the curriculum of numbers and number operations in elementary mathematics was analyzed. Based on the object-oriented design principle, "Number Classes" on numbers and number operations were designed and implemented. A class-based learning applet was developed with theses "Number Classes". It was developed in small unit programs based on learning themes of mathematics in elementary schools. With this learning applet, the active explorations through easy operations will help students to learn concepts and principles of numbers and number operations. It will strengthen active interactions of students with computer.

• ETRI Journal
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• v.31 no.5
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• pp.534-544
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• 2009

Finding link-disjoint or node-disjoint paths under multiple constraints is an effective way to improve network QoS ability, reliability, and so on. However, existing algorithms for such scheme cannot ensure a feasible solution for arbitrary networks. We propose design principles of an algorithm to fill this gap, which we arrive at by analyzing the properties of optimal solutions for the multi-constrained link-disjoint path pair problem. Based on this, we propose the link-disjoint optimal multi-constrained paths algorithm (LIDOMPA), to find the shortest link-disjoint path pair for any network. Three concepts, namely, the candidate optimal solution, the contractive constraint vector, and structure-aware non-dominance, are introduced to reduce its search space without loss of exactness. Extensive simulations show that LIDOMPA outperforms existing schemes and achieves acceptable complexity. Moreover, LIDOMPA is extended to the node-disjoint optimal multi-constrained paths algorithm (NODOMPA) for the multi-constrained node-disjoint path pair problem.

• Journal of Distribution Science
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• v.10 no.10
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• pp.5-9
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• 2012

Purpose - The purpose of this study is to explore, examine, and analyze Journal of Distribution Science and its articles based on five key factors of journal selection process by Thompson and to provide foundations for further knowledge creation and theory building in the areas of distribution and distribution science. Research design, data, methodology - This study used an exploratory case study method to engage article analysis and reviews of Journal of Distribution Science. Thompson's five journal selection factors were used as criteria for the journal and article analyses and review. Results - Journal of Distribution Science is currently meeting or at least in the progress of meeting the following factors: timeliness of publication, international editorial convention, international diversity, and citation analysis. However, JDS is short of meeting the factor of editorial content. The research topics were not new, emerging, and/or distinctive, and they were not directly associated with specific region or country other than Korea. Conclusions - The findings from this study could lead the field of distribution to reexamine the core knowledge, to reestablish the fundamental concepts and principles, to formulate and propose academically and practically sound research methods, and to develop and focus on unique research topics in the area of distribution.

• The Journal of Korean Association of Computer Education
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• v.11 no.4
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• pp.23-36
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• 2008

It's known by recent surveys that many students have difficulty in understanding the concepts of programming algorithms, and don't feel interested in learning them. Dynamic programming, one of the most important and widely-used algorithms in computer science, is especially feared by students and unlike other algorithms, it also requires understanding of the process of problem solving and storage space design as well as basic principles of the algorithm. And so it has not been properly covered in classes. In this paper, we developed a visual simulator to solve the above problems in learning dynamic programming. This learning simulator is designed for students to run the algorithms themselves and learn how it works by visualizing each step of dynamic programming and corresponding states of storage space.

• Journal of the Korea Society of Computer and Information
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• v.5 no.2
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• pp.37-42
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• 2000

Object technologies like the OMG's CORBA are enabling technologies the aim to facilitate integration implementation of diverse software components in distributed. heterogeneous environment. CORBA and similar object integration technologies define a standard component interconnection and inter-operation model , promote object-oriented principles to encapsulate incompatible component implementations. In this Paper. we present a connector model for software architectural representation of complex component collaborations. Our Connector model is base on research in software achitecture and object-oriented modeling. and part of a design framework for modeling component-based system. We believe the connector concepts to be vary benificial for a clear expression of dependencies between multiple component in Java Bean-based system.

• The Research Journal of the Costume Culture
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• v.27 no.6
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• pp.599-614
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• 2019

The aim of this study to provide basic reference data for the development of video contents used in pattern drafting education and to explore the possibility of utilizing YouTube videos in such education. Subject videos were selected using the number of views. A total of 596 videos and 28 channels were analyzed for the period July to September 2019 and the results are as follows. With regard to content, there were 27 pattern drafting items, the majority being dress, pants, skirt, blouse and sleeve drafting, although high-level content such as cowl, bustier, corset patterns were also available. Therefore, there is a high likelihood that YouTube videos could be used as educational material, especially as supplementary references to provide specific examples and easy explanations for difficult concepts or method, for students majoring in this field. However, as most videos currently focus on a few items, expanding video content to features a wider variety of clothing items at different levels is necessary. With regard to video length, it mostly ranged from 10 to 15 minutes. It is not advisable to create lengthy lecture-style videos expounding on different principles or variations in pattern drafting when developing educational video material.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.1
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• pp.67-76
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• 2012

Due to the increasing amount of applications of power electronic ac-dc converters, it is necessary to design a single-stage converter that can reliably perform both buck and boost operations. Traditionally, this can be achieved by double-stage conversion (ac/dc-dc/dc) which ultimately leads to less efficiency and a more complex control system. This paper discusses two types of modern ac-dc converters. First, the novel impedance-source ac-dc converter, abbreviated as custom Z-source rectifier, is analyzed; and then, switched inductor (SL) Z-source ac-dc converter is proposed. This paper describes the Z-source rectifiers' operating principles, the concepts behind them, and their superiorities. Analysis and simulation results show that the proposed custom Z-source rectifier can step up and step down voltage; and the main advantage of the SL Z-source ac-dc converter is its high step-up capability. Low ripple of the output dc voltage is the other advantage of the proposed converters. Finally, the SL Z-source ac-dc converter is compared with the custom Z-source ac-dc converter.

• Journal of Digital Contents Society
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• v.6 no.4
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• pp.217-222
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• 2005

The purpose of this study is to design and implement a sign language dictionary for the deaf to understand information communication terminologies. When the deafs who have difficulties in communication use the internet, they an get help from this dictionary in accessing various types of information and expressing their intension. In order for the deaf to utilize the internet as efficiently as ordinary people, they must understand information communication terminologies first In order to implement the dictionary, we defined the concepts of the deaf and examined their characteristics. In addition, we established principles in designing this dictionary and selected some terminologies. When explaining the terminologies. we tried to use expressions common to the deaf, but sometimes modified them to keep the original meanings of the terms in producing sign language videos. This studies are applied as learning aid to information education for the deaf, and the deaf's understanding of ICT was measured through two tests.