• 한국주조공학회지
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• 제30권1호
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• pp.34-45
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• 2010

The effects of alloy elements and cooling rate on the solidification path and the formation behavior of $\beta$ phase in Fe-containing Al-Si alloys were studied based on the thermodynamic analysis and the pertinent experiments. The thermodynamic calculation was systematically performed by using Thermo-Calc program. For the thermodynamic analysis in high alloy region of Al-Si-Fe ternary system, a thermodynamic database for Thermo-Calc was correctly updated and revised by the collected up-to-date references. For the thermodynamic-based prediction of various solidification paths in Fe-containing Al-Si system, liquidus projection of Al-Si-Fe ternary system, including isotherms, invariant, monovariant, bivariant reactions and equilibrium temperatures, was calculated and analyzed as functions of composition and temperature. The calculated results were compared to the experimental results using various casting specimens. In order to analyze various solidification sequences as functions of Si and Fe content, 4 representative alloy compositions, low Fe content in both low and high Si contents and high Fe content again in both low and high Si contents, were designed in this study. For better understanding of the influence of cooling rate on the formation behavior of $\beta$ phase, 4 alloys were solidified under furnace and rapidly cooled conditions. Cooling curves of solidified alloys were recorded by thermal analysis. Various important solidification events were evaluated using the first derivative-cooling curves. Microstructures of the casting samples were studied by the combined analysis of optical microscopy (OM) and scanning electron microscopy (SEM).

• 패션비즈니스
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• 제27권4호
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• pp.88-100
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• 2023

This study analyzed the compositional characteristics of fashion videos and the characteristics of fashion design spreading as trends through Subversive Basics. Literature research and case studies were conducted concurrently. Based on the literature review, an analysis method was designed, focusing on the concept of online video content, Subversive Basics, and the video content type. For the case analysis, videos were collected and classified using Subversive Basics as the keyword. The content was observed, and design features were analyzed. Based on the results, the collected videos were classified into tutorial, curation, and creative content types according to their compositional characteristics. Tutorial content emphasizes practical actions that demonstrate how to make or modify clothing, thereby promoting user-generated content for dissemination. Curation contents provide users with style ideas and information about clothing and purchases to encourage clothing purchases and influence purchase decisions that lead to dissemination through clothing consumption and wear. Creative content showcases the process of modifying and creating clothes to enhance understanding and value of creative design. The characteristics of fashion design utilized in these contents include bold designs with high visual effects as the first category, designs that can be easily and quickly modified due to intentional incompleteness as the second category, and prominently featured body-positive, individualistic designs as the third category. The results of this study can be associated with balanced development between basic design elements and personalized unique designs, catering to consumer needs.

• Advances in concrete construction
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• 제11권4호
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• pp.285-298
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• 2021

This study focused on experimental evaluation of mechanical properties of pervious concrete mixtures with the aim of achieving higher values of strength while considering the associated costs. The effectiveness of key parameters, including cement content, water to cement ratio (W/C), aggregate to cement ratio (A/C), and sand replacement was statistically analyzed using paired-samples t-test, Taguchi method and one-way ANOVA. Taguchi analysis determined that in general, the role of W/C was more significant in increasing strength, both compressive and flexural, than cement content and A/C. It was found that increase in replacing percent of coarse aggregate with sand could undermine specimens to percolate water, though one-way ANOVA analysis determined statistically significant increases in values of strength of mixtures. Cost analysis revealed that higher strengths did not necessarily correspond to higher costs; in addition, increasing the cement content was not an appropriate scenario to optimize both strength and cost. In order to obtain the optimal values, response surface method (RSM) was carried out. RSM optimization helped to find out that W/C of 0.40, A/C of 4.0, cement content of about 330 kg/m3 and replacing about 12% of coarse aggregate with sand could result in the best values for strength and cost while maintaining adequate permeability.

• ETRI Journal
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• 제27권5호
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• pp.595-607
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• 2005

The widespread use of the Internet has led to the problem of intellectual property and copyright infringement. Digital rights management (DRM) technologies have been developed to protect digital content items. Digital content can be classified into static content (for example, text or media files) and dynamic content (for example, VOD or multicast streams). This paper deals with the protection of a multicast stream on set-top boxes connected to an IP network. In this paper, we examine the following design and architectural issues to be considered when applying DRM functions to multicast streaming service environments: transparent streaming service and large-scale user environments. To address the transparency issue, we introduce a 'selective encryption scheme'. To address the second issue, a 'key packet insertion scheme' and 'hierarchical key management scheme' are introduced. Based on the above design and architecture, we developed a prototype of a multicasting DRM system. The analysis of our implementation shows that it supports transparent and scalable DRM multicasting service in a large-scale user environment.

• 한국콘텐츠학회논문지
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• 제13권3호
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• pp.485-494
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• 2013

본 논문에서는 내용 분석법(content analysis)과 Romey 분석법을 적용하여 공업계 고등학교 '정보 기술 기초' 교과서를 분석하였다. 내용 분석법으로 교과서의 구성 체계와 내용을 분석하였으며, Romey 분석법으로 4개의 분석요소인 본문, 자료, 활동, 평가에 대한 탐구적 경향을 분석하였다. 내용 분석법을 적용한 결과, 교과서를 구성하는 전체 페이지, 읽을거리, 영역별 개념의 수, 응용 소프트웨어 활용에서 교과서별로 차이가 있는 것으로 나타났다. Romey 분석법을 적용한 결과, 교과서 본문이 탐구적 경향이 낮은 권위적인 형태인 것으로 확인되었으며, 분석요소 중 활동에서 2개 교과서 모두 탐구적 경향이 높은 것으로 나타났다. 본 논문에서는 분석 결과를 바탕으로 '정보 기술 기초' 교과서의 개선 방안을 제안하였다.

• Journal of Plant Biotechnology
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• 제45권3호
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• pp.273-278
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• 2018

We performed an analysis of the effect of postharvest treatment of rhizomes of Aconitum septentrionale Koelle with the biological preparation of Bacispecin based on a cytokinin producing strain of Paenibacillus ehimensis IB-739 on the content of alkaloid lappaconitine in rhizomes. The total alkaloid content was assayed based on exhaustive extraction method. The lappaconitine content was measured by HPLC. The efficiency of the preparation was dependant on either the concentration or intensity of the growth processes in rhizomes. Both parameters varied depending on the stage of development of plants and the amount of precipitation. In the years with normal precipitation, concentrations of Bacispecin ranging from 5 to 10 g/l were found to be most effective for increasing lappaconitine content in rhizomes of A. septentrionale. Whereas, under local drought conditions, the concentration of preparation should be less than 2 g/l.

• Journal of Information Science Theory and Practice
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• 제5권2호
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• pp.6-16
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• 2017

Populating information-rich online environments through crowdsourcing is increasingly becoming popular. One approach to motivate participation is via games. That is, a crowdsourcing game offers entertainment while generating useful outputs as byproducts of gameplay. A gap in current research is that actual usage patterns of crowdsourcing games have not been investigated thoroughly. We thus compare content creation patterns in a game for crowdsourcing mobile content against a non-game version. Our analysis of 3,323 contributions in both apps reveal 10 categories including those that conform to the traditional notion of mobile content created to describe locations of interest, and those that are social in nature. We contend that both types of content are potentially useful as they meet different needs. Further, the distribution of categories varied across the apps suggests that games shape behavior differently from non-game-based approaches to crowdsourcing.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2319-2337
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• 2019

In this paper, we study the distributed cooperative caching for Internet content providers in a small cell of heterogeneous network (HetNet). A general framework based on bankruptcy game model is put forth for finding the optimal caching policy. In this framework, the small cell and different content providers are modeled as bankrupt company and players, respectively. By introducing strategic decisions into the bankruptcy game, we propose a caching value assessment algorithm based on analytic hierarchy process in the framework of bankruptcy game theory to optimize the caching strategy and increase cache hit ratio. Our analysis shows that resource utilization can be improved through cooperative sharing while considering content providers' satisfaction. When the cache value is measured by multiple factors, not just popularity, the cache hit rate for user access is also increased. Simulation results show that our approach can improve the cache hit rate while ensuring the fairness of the distribution.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.229-232
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• 2004

In this paper, we propose a robust music retrieval system based on the content analysis of music. New feature extraction method called Multi-Feature Clustering (MFC) is proposed for the robust and optimum performance of the music retrieval system. It is demonstrated that the use of MFC significantly improves the system stability of music retrieval with better classification accuracy.

• 성인간호학회지
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• 제17권3호
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• pp.411-424
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• 2005

Purpose: The purpose of this study was to develop and evaluate e-EBPP(Evidence-based Practice Protocol) system for nursing care for patients with dementia to facilitate the best evidence-based decision in their dementia care settings. Method: The system was developed based on system development life cycle and software prototyping using the following 5 processes: Analysis, Planning, Developing, Program Operation, and Final Evaluation. Result: The system consisted of modules for evidence-based nursing and protocol, guide for developing protocol, tool for saving, revising, and deleting the protocol, interface tool among users, and tool for evaluating users' satisfaction of the system. On the main page, there were 7 menu bars that consisted of Introduction of site, EBN info, Dementia info, Evidence Based Practice Protocol, Protocol Bank, Community, and Site Link. In the operation of the system, HTML, JavaScript, and Flash were utilized and the content consisted of text content, interactive content, animation, and quiz. Conclusion: This system can support nurses' best and cost-effective clinical decision using sharable standardized protocols consisting of the best evidence in dementia care. In addition, it can be utilized as an e-learning program for nurses and nursing students to learn use of evidence based information.