• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.6
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• pp.1312-1317
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• 2013

Pseudolite is a contraction of the term "pseudo-satellite", used to refer to something that is not a satellite which performs a function commonly in the domain of satellites. Pseudolite are most often small transceivers that are used to create a local, ground-based GPS alternative. Pseudo-range measurement of pseudolite has around 300m range error, when time synchronization error of $1{\mu}sec$ occurs. Therefore the time synchronization methods play an important part in navigation augmentation using pseudolite. This paper proposes three clock synchronization methods that are installation method of pseudolite station, method using KRISS-UTC and method using PRN code phase difference for pseudolite. The simulation platform structure is presented for evaluating proposed clock synchronization performance.

• Communications for Statistical Applications and Methods
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• v.16 no.3
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• pp.421-428
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• 2009

On the visualization of categorical data, if the number of categories is small, we can consider Hayashi Quantification Method 3 for visualization of the categories of the variables. But it is known that the method is unstable because it quantifies more significantly for the small frequency categories rather than large frequency categories. The purpose of this research is to propose the visualization of large two-way crosstabulation data by PLS methods for checking the relationship between the categories of row and column variables. In this research, we utilize the PLS visualization methods (Huh et al., 2007) that is proposed for visualization of the qualitative data to visualize the categories of the large categorical data. We also compared both methods by applying them to real data, and studied the results from PLS visualization method on the real categorized data with many categories.

• Journal of Digital Convergence
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• v.18 no.11
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• pp.443-448
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• 2020

The purpose of research is identifying visual factors affecting purchase of convenient store packed-meals through mobile applications. Previous studies have not covered mobile applications on purchase of convenient store packed-meals and this inspired the research topic. Document analysis and online survey are mainly implemented and 4 visual factors; typography, product image, main color, brand logo have been set as a research variables. It is revealed that consumers recognize product image prior to the rest and their purchase intentions are most significantly affected by product image. In conclusion, the product image should encourage consumers to have expectation on packed-meal and need to deliver credibility at the same time. Hence, the application should be designed to solely spotlight product image to lead consumer's concentration on it. The research can be further expanded by including non-visual factors as its variables or increasing scale of survey samples.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.38 no.5
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• pp.1-15
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• 2001

Expressing complex query conditions in a concise and intuitive way has been a challenge in the design of visual object-oriented query languages. We propose a visual query language called VOQL (Visual Object oriented Query Language) for object oriented databases. By employing the visual notation of graph and Venn diagram, the database schema and the advanced features of object oriented queries such as multi-valued path expressions and quantifiers can be represented in a simple way. VOQL has such good features as simple and intuitive syntax, well-defined semantics, and excellent expressive power of object-oriented queries compared with previous visual object-oriented query languages.

• Journal of the Korean Chemical Society
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• v.51 no.5
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• pp.423-432
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• 2007

In this study we investigated the types of inscriptions representing the concept of atom and molecule in the 9th grade science textbooks developed under the 7th National Curriculum, and analyzed the processes of interpreting those inscriptions on the view of semiotics. The concept of atom and molecule was represented in various ways such as circular diagram, matters of everyday life, ball-and-stick, and STM graphic, etc. We identified two kinds of inscriptions on the basis of the possibilities of handling models: the inscriptions that represent concept of atom and molecule by image; the inscriptions that represent concept of atom and molecule by using specific matters. We analyzed the processes of interpreting inscriptions systematically with a semiotic model that includes ‘structuring processes' and ‘translating processes'. The interpretation of inscriptions representing concept of atom and molecule was a complex process requiring many steps of interpreting works. Educational implications of these findings are discussed.

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.59-71
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• 2020

The purpose of this study is to determine whether vision therapy improves symptom and visual perceptual skills in children with attention deficit hyperactivity disorder tendency who have visual problems. The subjects of this study were 10 children. Before and after vision therapy, the visual function test, developmental test of visual-motor integration, test of visual perceptual skills, and ADHD rating scale test were performed. Vision therapy was conducted twice a week for a period of 6 months to 1 year. After vision therapy, all subjects achieved normal ranges of visual function, sensory fusion, stereoacuity, vergence function, and convergence. The visual function and visual perceptual skill were improved and the score for ADHD symptoms was reduced. Therefore, it seems that vision therapy can be used to improve the symptoms and visual perception of children with ADHD.

• 한국벤처창업학회:학술대회논문집
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• 2016.04a
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• pp.154-156
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• 2016

이 연구의 목적은 소비자의 구매의도를 자극하고, 판매를 촉진시켜주는 구매시점광고(POP Ad: Point Of Purchase Advertising)의 소매판매 유통점 활용영역에서 정보전달형태 변화에 따른 광고효과 차이가 있는지를 연구하는데 있다. 연구의 배경과 방법은 통상의 구매시점광고가 정보전달 방법에 있어서 소비자 구매활동 장소 내 외에서 단순 비치, 설치된 상태로서 기능과 역할을 수행하고 있음을 착안, 광고소구형태를 시각, 청각 그리고 인적판매원이 관여된 혼합(시각, 청각)형으로 분류하여 정보를 전달 한 후 소비자의 태도 및 매출 비교를 위해 실증적 실험을 했다. 본 연구의 핵심 가설은 '인적판매원이 개입된 혼합형(시각, 청각) 구매시점광고가 소비자 태도(신뢰도/호감도/구매의도) 및 매출( + / -)영향도가 더욱 높게 나타날 것이다'이다. 이는 소비자에게 시각, 청각이 동시에 전달되는 혼합소구유형은 정보전달력이 우수하고, 광고 효과성이 높을 것이다를 검증하기 위한 것이다. 본격 연구 전에 실시한 1차 사전적 실증 실험결과 소비자가 지각하는 관점에 따라 시각형(광고의 정보내용을 인쇄물로 제공), 청각형(광고의 정보내용을 소리전달형태로 제공), 시각, 청각 혼합형(인적판매원이 시각형 정보를 활용 광고내용을 직접 전달)분류한 3가지 유형간 정보전달 효과의 차이는 없는 것으로 나왔다. 하지만, 본 연구는 생계형 소매유통 창업현장에서 활동하고 있는 소상공인들이 구매시점광고를 광고의 활용측면에서 능동형 마케팅 활동 도구로 사용할 수 있는지에 대한 실증적 사례 분석을 했다는 것에 의의를 두고자 한다. 업종별 차이는 있지만 대부분의 소상공인들의 마케팅 환경은 열악하다. 마케팅 전담 인력의 부재, 마케팅 지식의 부족, 전방위적 마케팅 전개 시간의 한계 등으로 인해 체계적으로 마케팅활동을 펼 칠 수 없는게 현실이다. 이에 현장 활용성이 높은 효율적이고 효과적인 구매시점광고의 광고정보전달 연구 및 개발이 요구된다고 보며, 이에 관한 지속적인 후행적 연구와 노력이 필요하다고 사료된다.

• Journal of Internet Computing and Services
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• v.15 no.6
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• pp.65-75
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• 2014

The main focus of this paper is to analyze trend of event informations in a variety of mass media by graphical visualization in axis of the time and location. Especially, continuity analysis based on user-generated social media can reflect the social impact of a certain event according to change time and location and their directional changes. To reveal the characteristics of continuous events, we survey the data set collected from news articles and tweets during two years. Based on case studies on 'disease' and 'leisure', we verify the effectiveness and usefulness of our proposed method. Even though some events occurred during same period, we showed directional changes which have high-impact in social media referred user interest's, compared with fact-based continuous visualization results.

• Journal of Science and Technology Studies
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• v.11 no.2
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• pp.67-96
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• 2011

Studies in scientific visualization have disclosed a visual chain among many scientific visualizations, which starts from the photographs that have many details to diagrams that enable scientists to make specific claims due to their abstract characters. Located at both ends of the visual chain, photographs and diagrams are regarded as being different kinds and having different characteristics. The photographs - or microphotographs to be precise - that this paper discusses, however, had been removed of unnecessary details and were prepared with carful attention to illustrative functions that diagrams usually perform. Following microphotographic changes in a Korean laboratory, this article shows that the knowledge of specimen preparation was transmitted from an American leading group to the Korean laboratory through a direct contact, and that with this, the technique of taking microphotographs of the laboratory was much improved. The specimen preparation method is, however, a tacit knowledge that is invisible in both group's papers. This article argues that the method of specimen preparation is the driving force that made the microphotographs act like carefully prepared diagrams and acquire objectivity.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.7
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• pp.273-281
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• 2003

This paper proposes a new time synchronization scheme for the Automatic Identification System(AIS). The proposed scheme utilizes a Temperature Compensated Crystal Oscillator(TCXO) as a local reference clock, and consists of a Digitally Controlled Oscillator(DCO), a divider, a phase comparator, and register blocks. Primary time reference is IPPS from GPS receiver that is synchronized to Universal Time Coordinated(UTC). And if GPS is unavailable, other station's signal is utilized as secondary time reference. The phase comparator measures time difference between the 1PPS and the generated transmit clock. The measured time difference is compensated by controlling the DCO and the transmit clock is synchronized to the Universal Time Coordinated(UTC). The synchronized transmit clock(9600Hz) is divided into the transmitting time slot(37.5Hz). The proposed scheme is tested in an experimental AIS transponder set. The experimental result shows that the proposed module satisfies the timing specification of the AIS technical standard, ITU-R M.1371-1.