• 전력전자학회:학술대회논문집
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• 전력전자학회 2020년도 전력전자학술대회
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• pp.79-81
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• 2020

임계모드 (Critical conduction mode, CrM) 동작을 하는 PFC 컨버터는 주파수 변동을 통한 Valley switching 동작으로 인하여 높은 효율 및 양호한 EMI 특성을 가진다. 하지만 Peak 부하가 큰 시스템에서 CrM 설계를 하게 되면 정격부하에서 비교적 높은 주파수의 동작이 불가피하여 시스템 효율이 나빠지고 높은 DC-bias 확보를 위해 인덕터 크기가 커지게 된다. 따라서 본 논문에서는 고효율 및 인덕터 사이즈 저감을 위한 임계모드에서 동작하는 두 개의 교차형 PFC 컨버터의 병렬 구동에 대해서 이야기하고자 한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2012년도 추계학술발표대회
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• pp.1736-1738
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• 2012

광대역 유무선 네트워크 기술과 컴퓨팅 기술의 발전으로 스마트 TV, 스마트 폰, 태블릿 PC와 같은 스마트단말의 등장으로 사용자가 여러 단말을 가지게 되었으며, 상황에 따라 가장 적합한 단말을 사용하거나 보유한 여러 단말을 함께 사용하여 새로운 멀티미디어 사용 경험을 하게 되었다. 또한 W3C은 웹 환경에서 다양한 웹 어플리케이션 개발의 기반이 되는 HTML5 표준과 개방형 웹 플랫폼을 제안하고 있다. 본 논문에서는 다양한 단말에서 지원하고 있는 웹 기반 플랫폼을 기반으로 웹 콘텐츠와 웹 서비스를 공유할 수 있는 공유 스크린 서비스 플랫폼의 기능을 도출하고 플랫폼을 설계한다.

• 정보보호학회논문지
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• 제7권4호
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• pp.37-50
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• 1997

시각암호는 기존의 비밀 분산법이 비밀을 분산/복호시의 방대한 연산량을 수반하는 것과는 달리 인간의 시각에 의해 직접 복호되기 때문에 복잡한 연산이 필요없는 방식이다. 본 논문에서는 중첩하는 슬라이드의 매수에 따라 복수의 비밀화상이 복원되는 시각암호에 대해 알아보고, 그 안전성을 검증한다. 분산하고자 하는 비밀화상의 수가 증가함에 따라 크기가 기하 급수적으로 커지기 때문에 복원화성의 인식이 어렵게 된다. 따라서 고정 가중치 부호의 해밍 거리를 조정하여 줄임으로서 복원화상의 해상도를 개선하는 방법을 제안한다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권5호
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• pp.658-665
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• 2014

The neural stimulators have been employed to the visual prostheses system based on the functional electrical stimulation (FES). Due to the size limitation of the implantable device, the smaller area of the unit current driver pixel is highly desired for higher resolution current stimulation system. This paper presents a 16-channel compact current-mode neural stimulator IC with digital to analog converter (DAC) sharing scheme for artificial retinal prostheses. The individual pixel circuits in the stimulator IC share a single 6 bit DAC using the sample-and-hold scheme. The DAC sharing scheme enables the simultaneous stimulation on multiple active pixels with a single DAC while maintaining small size and low power. The layout size of the stimulator circuit with the DAC sharing scheme is reduced to be 51.98 %, compared to the conventional scheme. The stimulator IC is designed using standard $0.18{\mu}m$ 1P6M process. The chip size except the I/O cells is $437{\mu}m{\times}501{\mu}m$.

• 대한음성학회지:말소리
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• 제60호
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• pp.29-45
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• 2006

We investigated whether the first syllable plays an important role in lexical access in Korean visual word recognition. To do so, one lexical decision task (LDT) and two form primed LDT experiments examined the nature of the syllabic neighborhood effect. In Experiment 1, the syllabic neighborhood density and the syllabic neighborhood frequency was manipulated. The results showed that lexical decision latencies were only influenced by the syllabic neighborhood frequency. The purpose of experiment 2 was to confirm the results of experiment 1 with form-primed LDT task. The lexical decision latency was slower in form-related condition compared to form-unrelated condition. The effect of syllabic neighborhood density was significant only in form-related condition. This means that the first syllable plays an important role in the sub-lexical process. In Experiment 3, we conducted another form-primed LDT task manipulating the number of syllabic neighbors in words with higher frequency neighborhood. The interaction of syllabic neighborhood density and form relation was significant. This result confirmed that the words with higher frequency neighborhood are more inhibited by neighbors sharing the first syllable than words with no higher frequency neighborhood in the lexical level. These findings suggest that the first syllable is the unit of neighborhood and the unit of representation in sub-lexical representation is syllable in Korea.

• 한국콘텐츠학회논문지
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• 제11권2호
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• pp.303-311
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• 2011

21C를 살아가는 우리에게 TV나 영화, 잡지, 인터넷 등 다양한 매체나 영상물은 이제 없어서는 안 될 존재이다. 시대가 바뀌고 무한한 정보의 공유와 기계의 발전으로 인해 유행과 사상이 빠르게 전달되고 있으며, 좀 더 감각적이고 자극적인 것을 추구하는 경향이 있다. 우리 주위에는 마치 공기처럼 특별한 존재감 없이 인간의 식별능력을 넘어선 수많은 색(컬러)이 있다. 이러한 컬러는 시각문화에 직접적인 영향을 주게 되고, 그 시대의 트렌드(trend)를 가장 빠르게 반영하게 된다. 바로 이 점에서 최근 각광받고 있는 네온컬러의 중요성이 부각되어 나타나고 있다. 그러나 여러 선행 연구에서 컬러에 대한 연구는 많이 이루어져 왔으나 네온컬러에 대한 연구는 이루어 지지 않고 있어 네온컬러 연구의 필요성을 느끼게 되었다. 이와 같이 시각문화 속에서의 컬러의 중요성과 그 심리를 파악하며 네온컬러의 특성과 시각문화가 연관성이 있는지 알아내고 그것을 어떻게 미술교육에 응용하여 실연(實演)할 것인가를 연구 하였다.

• International Journal of Computer Science & Network Security
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• 제22권6호
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• pp.230-240
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• 2022

Sharing of online videos via internet is an emerging and important concept in different types of applications like surveillance and video mobile search in different web related applications. So there is need to manage personalized web video retrieval system necessary to explore relevant videos and it helps to peoples who are searching for efficient video relates to specific big data content. To evaluate this process, attributes/features with reduction of dimensionality are computed from videos to explore discriminative aspects of scene in video based on shape, histogram, and texture, annotation of object, co-ordination, color and contour data. Dimensionality reduction is mainly depends on extraction of feature and selection of feature in multi labeled data retrieval from multimedia related data. Many of the researchers are implemented different techniques/approaches to reduce dimensionality based on visual features of video data. But all the techniques have disadvantages and advantages in reduction of dimensionality with advanced features in video retrieval. In this research, we present a Novel Intent based Dimension Reduction Semi-Supervised Learning Approach (NIDRSLA) that examine the reduction of dimensionality with explore exact and fast video retrieval based on different visual features. For dimensionality reduction, NIDRSLA learns the matrix of projection by increasing the dependence between enlarged data and projected space features. Proposed approach also addressed the aforementioned issue (i.e. Segmentation of video with frame selection using low level features and high level features) with efficient object annotation for video representation. Experiments performed on synthetic data set, it demonstrate the efficiency of proposed approach with traditional state-of-the-art video retrieval methodologies.

• 정보기술과데이타베이스저널
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• 제8권1호
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• pp.1-11
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• 2001

More and more cyber shopping malls, one of the new promising Internet businesses of today, are opening business everyday. And instead of the ordinary image and text type of product display, buyers can now view products from any viewpoint through 3D images and also get more detail information on the product more easily thanks to the new VP technology, visual tools, and statecharts. However the currently used virtual prototyping supporting method does not consist of any database support for sharing the data from different virtual prototype developments and reusing the data in developing other prototypes. And in cases of custom order products, there is no linkage with the virtual product database that enables buyers in cyberspace such as cybermalls to try out the products before purchasing. This paper is purported for being applied as the basis for planning the construction of a complete CRM method applied cyber shopping mall that can accommodata all the demands and requests from customers. And the database supporting VP framework that supports data sharing and collaboration between virtual prototype developers and manufacturing custom order products is suggested for this purpose.

• 복식
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• 제61권7호
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• pp.80-100
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• 2011

The purpose of this research is to classify that fashion and art in the twentieth century broadened the creative field by individually applying each other's ideas or through collaboration. This paper analyses the work of individual artists and fashion designers who created work on the boundaries of fashion and art. These samples are selected to extract features related to specific periods as it is proposed that contemporary creation has been developed from a combination of fashion and art, sharing their distinct concerns. Accordingly, this research will focus on the collaboration between fashion and art in the twentieth century from the aspect of 'fashion into art'/'art into fashion' in order to analyse the historical flow, and thereby examine the relationship between fashion and art. The cross-fertilization between fashion and art was initiated as an imitation of form in the early twentieth century, and led to a 'new cross-disciplinary form' which exists on the boundary of fashion and art. This paper considers the relationship between fashion and art from the perspective of sharing intrinsic concepts and the creation of a new creative sphere. It analyses the characteristics of the works of fashion designers and artists whose works lie on the boundary between fashion and art.

• Computers and Concrete
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• 제7권3호
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• pp.249-269
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• 2010

Managing and reusing knowledge in engineering and construction sectors can lead to greater competitive advantage, improved designs, and more effective management of constructed facilities. The use of Information Technology (IT) in design and construction can exploit strategic opportunities for new ways of integration, sharing and facilitating information and knowledge in any field of engineering. The integrating of separate areas of IT can be used to bring a group of experts and specialists in any field of engineering closer together by allowing them to communicate and exchange information and expertise that facilitate knowledge capture, sharing, and reuse. A lack of an advisory management system and a need to marshal all available data in a common format has indicated the need for an integrated engineering computing environment to investigate concrete repair problems. The research described in this paper is based upon an evaluation management system (EMS) which comprising a database management system (REPCON) alongside visualisation technologies and evaluation system (ECON) is developed to produce an innovative platform which will facilitate and encourage the development of knowledge in educational, evolution and evaluation modes of concrete repair. This allows us to create assessment procedures that will allow the current condition of the concrete structure and its components to be expressed numerically using a confidence level (CL) so as to take the best course of action in the repair and maintenance management. The explained rating system, which is related to structural integrity and serviceability of the structure, allows the confidence level to be determined by visual inspection and the descriptive information and pictures taken from an available REPair of CONcrete (REPCON) database.