• ETRI Journal
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• v.28 no.3
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• pp.364-366
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• 2006

This letter introduces an efficient transmission of traffic information through a terrestrial digital multimedia broadcasting system, which is a multimedia and mobility empowered option of the European digital audio broadcasting system. By adapting Korean characteristic traffic information into the transport protocol expert group messages in the traffic information delivery, a highly efficient traffic information system was implemented and tested in Korea.

• Fire Science and Engineering
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• v.29 no.6
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• pp.13-19
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• 2015

This study was performed to test the combustive properties of Pinus rigida specimens treated with phosphorus (P) and nitrogen (N) additives. Each Pinus rigida specimen was painted three times with 15 wt% P-N additive solutions at room temperature. After drying the treated specimens, the combustion properties were examined using a cone calorimeter (ISO 5660-1). The time to ignition (TTI) for the treated specimens was 90 to 148 s except for the specimen treated with PP/$4NH_4^+$, and the time to flameout (TF) was 556 to 633 s, which was longer than that of virgin plate. While the The specimens treated with P-N additives showed 12.5 to 43.4% higher mean heat release rate ($HRR_{mean}$) and 11.8 to 43.1% higher total heat release (THR) than virgin plate. The effective heat of combustion (EHC) was by 2.9 to 17.5% lower than that of virgin plate. It can thus be concluded that the combustion-retardation properties were partially improved compared to those of virgin plate.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.127-130
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• 2005

우수한 이동수신 성능을 지닌 지상파 DMB(T-DMB: Terrestrial-Digital Multimedia Broadcasting)의 킬러앱(Killer App)이라 불리는 교통 및 여행정보(TTI: Traffic and Travel Information) 서비스는 주 5일 근무제 실시와 지속적인 자동차수 증가로 인해 그 중요성이 부각되고 있다. 지상파 DMB 기반의 TTI 서비스 전송을 위한 프로토콜로 국제 표준인 TPEG(Transport Protocol Expert Group)이 유력시 되고 있으나, 현재 국제 표준화가 완료된 서비스 규격으로는 속도 ${\cdot}$ 유고정보 및 대중교통수단 관련 정보 전송이 가능한 RTM(Raod Traffic Message)과 PTI(Public Transport Information) 뿐이다. 국내의 경우, 속도 정보 제공을 위한 새로운 서비스 규격으로 CTT(Congestion and Travel Time Information)에 대한 표준화 작업이 진행 중에 있다. 최근 이동통신 인프라 대신 지상파 DMB를 기반으로 한 새로운 위치기반서비스의 규격 제정의 필요성이 대두되었으며, 이에 따라 이를 위한 국내 표준화 활동이 본격적으로 추진될 예정이다. 본 논문에서는 기존 TPEG 규격과 완벽히 호환되는 위치기반서비스 전송을 위한 새로운 POI(Point Of Interest) 프로토콜을 제안하였다. 이의 검증을 위해 POI 데이터 서비스 저작 및 전송서버 및 POI 수신 플랫폼을 설계 ${\cdot}$ 구현하여 송수신 플랫폼을 구성하였으며, 구축된 플랫폼을 이용한 방송실험을 통해 제안된 POI 서비스 응용 프로토콜의 안정성 및 전송 효율성을 확인하였다.

• Journal of the Korea Convergence Society
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• v.5 no.3
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• pp.1-5
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• 2014

The development of communication method for a variety of intelligent automobiles are delivering comfortable and safe information. However the development of such communication method must also think about security. Even the update of navigation to be used for intelligent automobiles uses the wireless updating methods but the updating methods currently being used has no reliable security measures. The navigation communications used in the intelligent automobiles are being provided with TTI(Traffic and Travel Information) service using a variety of methods by the countries. In the case of Korea, most are based on T-DMB using the TPEG method for transmitting the information. By identifying the characteristics on the navigation wireless update, a security solution is proposed for delivering the reliable update information after creating the attack scenario.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.5
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• pp.508-516
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• 1992

In this study, dielectric and piezoelectric properties of 0.05Pb(AlS12/3TWS11/3T)OS13T-0.95Pb(ZrS10.52TTiS10.48T)OS13T system ceramics were investigated with respect to the variations of MnOS12T and FeS12TOS13T additions amounts. The results obtained in this study are summarized as follows: 1. As the amounts of MnOS12T and FeS12TOS13T are increased, tetragonality(c/a) and apparent density were decreased but grain size was increased, also the limits of solubility were revealed because pores were formed at the amounts of 0.3wt% MnOS12T and 0.5wt% FeS12TOS13T. 2. AS the increasing of amounts of MnOS12T and FeS12TOS13T, the temperature of phase transition(TS1cT) was decreased, and pemeability had maximum value at the amount of 0.3wt% MnOS12T but were sharply decreasd for the increasing FeS12TOS13T amounts. 3. As the amounts of MnOS12T and FeS12TOS13T are increased, the electro-mechanical coupling factor(kS1pT) was decreased from 60% to 41%, 19% respectively, but mechanical quality factor(QS1mT) had maximum values 720 for amount of 0.3wt% MnOS12T and 320 the amount of 0.5wt% FeS12TOS13T.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.462-470
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• 2011

ARS (Automatic Response Systems) based on VUI (Voice User Interface) and TTI (Touch Tone Interface) are one of the most widely used communication systems. Despite common usages, however, inconvenience of ARS is continually pointed out. This may stem from lack of human-centered studies aside from technological development. In this paper, we provide guidelines for designing ARS by analyzing hindrance factors of usability of ARS menu structure. We had selected two call-centers using ARS, and carried out an experimental study where subjects performed the task of "returning books." After that, they completed questionnaires and interviews. We identified four problems: the complex menu structure, lack of representativeness on the menu name, users' awareness of location, and a difficulty to move among menus. And we partially discussed the ways of avoiding the problems.

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.57-62
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• 2016

PURPOSES : Reflection cracking has been one of the major causes of distress when asphalt pavement is laid on top of concrete pavement. This study evaluated the reflection cracking resistance of asphalt mixtures reinforced with asphalt embedded glass fiber and carbon fiber using a Texas Transportation Institute (TTI) overlay tester. METHODS : Different asphalt mixtures such as polymer-modified mastic asphalt (PSMA) and a dense graded asphalt mixture were reinforced with asphalt-embedded carbon fiber and glass fiber. For comparison purposes, two PSMA asphalt mixtures and one dense graded asphalt mixture were evaluated without fiber reinforcement. Two different overlay test modes, the repeated overlay test (R-OT) and monotonic overlay test (M-OT), were used to evaluate the reflection cracking resistance of asphalt mixtures at $0^{\circ}C$. In the R-OT test, the number of repeated load when the specimen failed was obtained. In the M-OT test, the tensile strength at the peak load and tensile strain were obtained. RESULTS : As expected, the fiber-reinforced asphalt mixture showed a higher reflection cracking resistance than the conventional nonreinforced asphalt mixtures based on the R-OT test and M-OT test. The dense graded asphalt mixture showed the least reflection cracking resistance and less resistance than the PSMA. CONCLUSIONS : The TTI overlay tester could be used to differentiate the reflection cracking resistance values of asphalt mixtures. Based on the R-OT and M-OT results, the carbon-fiber-reinforced asphalt mixture showed the highest reflection cracking resistance among the nonreinforced asphalt mixtures and glass-fiber-reinforced asphalt mixture.

• Ocean and Polar Research
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• v.43 no.1
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• pp.31-43
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• 2021

To understand the temporal variation of prokaryotic communities in a temperate coastal area, prokaryotic abundance, activity, and community composition were investigated every week for over a year at a coastal monitoring station of Yeong-do, Busan. The prokaryotic abundances fluctuated about 10 times, ranging from 2.0 to 20.1 × 10⁵ cells mL^-1 and tended to be high in spring when phytoplankton bloom occurred. The prokaryotic thymidine incorporation rates (TTI) varied in a low range between 0.2 and 11.5 pmol L^-1 h^-1 in winter. However, in summer, TTI were increased up to a range of 8.3 to 17.4 pmol L^-1 h^-1, showing an increasing pattern in summer. During the study period, Alphaproteobacteria was the most dominant class for most of the year, followed by Flavobacteria. While the seasonal variation of prokaryotic composition was not apparent at the class level, many prokaryotic species showed a distinct temporal or seasonal variation for the year. In the coastal site, prokaryotic biomass and activity did not show significant correlations with temperature and chlorophyll-a, which are well known to regulate prokaryotic growth in marine environments, suggesting that the study area may be affected by diverse sources of organic matter for their growth.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2007.05a
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• pp.179-188
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• 2007

디지털 기기 가 보편 화 되 면서 많 은 디지털 컨텐츠가 생성되고 있다. 또한, 인터넷 서비스의 발전으로 이들 컨텐츠를 과거에 비해 손쉽게 웹 상에 개제할 수 있게 되 었다. 따라서, 많은 컨텐츠를 추 천해 주기 위해 추천 시스템에 관한 연구가 활발히 진행되고 있다. 이들 컨텐츠가 기존의 텍스트 기반에서 사진이나 동영상, 사운드 등 컴퓨터가 자동으로 내용을 파악하기 힘든 컨텐츠로 변화하면서, 내용의 파악이 필요 없 는 협력적 여 과(Collaborative Filtering)가 추천 시스템에서 유 용하게 이 용될 수 있다. 또한 web 2.0의 영향으로 컨텐츠를 분류하고 재검색을 용이하게 하기 위해 태깅(tagging)을 제공하는 서비스가 많아지고 있다. 본 논문에서는 내용 파 악이 힘든 컨텐츠의 효과적인 추천을 위해 협력적 여과(Collaborative Filtering)와 협력적 태깅(Collaborative Tagging)을 접목시킨 방법을 제안하고, 전통적인 협력적 여과 방법과 제안한 방법의 비교 실험을 통하여 협력적 여과 방법에서의 태 깅의 효과에 대 해 논한다.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.121-126
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• 1994

To elucidate the effect on the reactive extraction of acetic acid, various carriers and modifiers were investigated. Carriers used were secondary and tertiary amines and solvation extractant. Diluent was n-butylacetate. Modifiers were 4-nonylphenol, TBP(Tti-n-butyl phospate) and isodecanol. Besides the effect of temperature and pH in aqueous phase were studied. The mixture of 50% tri-n-octyl/n-decylamine tertiary amine, gave higher degree of extraction and selectivity than other extractants in the extraction of acetic acid. It was found that 4-nonylphenol as modifier fairly good. The degree of extraction was higher with decreasing the pH in aquous phase and the temperature of extraction system.