• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1460-1478
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• 2020

This paper proposes a novel anti-collision protocol for large-scale RFID tags identification, named Bi-response Collision Tree Protocol (BCT). In BCT, two group of tags answer the reader's same query in two response-cycles respectively and independently according to the bi-response pattern. BCT improves the RFID tag identification performance significantly by decreasing the query cycles and the bits transmitted by the reader and tags during the identification. Computation and simulation results indicate that BCT improves the RFID tag identification performance effectively, e.g. the tag identification speed is improved more than 13.0%, 16.9%, and 22.9% compared to that of Collision Tree Protocol (CT), M-ary Collision Tree Protocol (MCT), and Dual Prefix Probe Scheme (DPPS) respectively when tags IDs are distributed uniformly.

• 기술혁신학회지
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• 제5권2호
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• pp.228-244
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• 2002

The survey of research and development (R&D) in science and technology (S&T) covers the current status of R&D activities in S&T in Korea, and provides a basis for decision making regarding S&T policy. Continuous improvement of the survey is widely needed to present reliable national basic statistics. Therefore, the purpose of the study is two-fold: to introduce sampling survey method in industrial sector and to make statistical technique to deal with non-response data from industrial sector. To these ends, first, case studies of the United States and Japan are illustrated. A new sampling design for the R&D survey is proposed and implementing stratified random sampling scheme is suggested. Moreover, statistical analysis of the non-response data is dealt with. Based on several screening criteria, we develop a new imputation method suitable for the R&D survey and also provide more detailed implementation plan. Various solutions to a problem arising from non-response item are also presented. Finally, some implications of the results are discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.691-694
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• 2006

So far, we have done much research improving quality of LCD TV. Recently, we have developed 26" WXGA LCD TV by advance fringe field switching (AFFS) technology with smooth and every scene realistic in color image that obtained from the amazing authentic color delivery, optical characteristic and fast response time. Our upgrade device has shown the brightness over 600nits (Color shift <0.015 and Transmittance ratio > 5.5%), gray to gray response time under 6ms, contrast ratio over 1200:1 and viewing angle over 178/178, respectively. And also, motion artifacts improved by fast response of LC with low viscosity, cell gap and dielectric constant.

• Wind and Structures
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• 제38권3호
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• pp.215-229
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• 2024

Guyed mast structures exhibit characteristics such as high flexibility, low mass, small damping ratio, and large aspect ratio, leading to a complex wind-induced vibration response mechanism. This study analyzed the time- and frequency-domain characteristics of the wind-induced response of a guyed mast structure using measured acceleration response data obtained from the Shenzhen Meteorological Gradient Tower (SZMGT). Firstly, 734 sets of 1-hour acceleration samples measured from 0:00 October 1, 2021, to 0:00 November 1, 2021, were selected to study the vibration shapes of the mast and the characteristics of the generalized extreme value (GEV) distribution. Secondly, six sets of typical samples with different vibration intensities were further selected to explore the Gaussian property and modal parameter characteristics of the mast. Finally, the modal parameters of the SZMGT are identified and the identification results are verified by finite element analysis. The findings revealed that the guyed mast vibration shape exhibits remarkable diversity, which increases nonlinearly along the height in most cases and reaches a maximum at the top of the tower. Moreover, the GEV distribution characteristics of the 734 sets of samples are closer to the Weibull distribution. The probability distribution of the structural wind vibration response under strong wind is in good agreement with the Gaussian distribution. The structural response of the mast under wind loading exhibits multiple modes. As the structural response escalates, the first three orders of modal energy in the tower display a gradual increase in proportion.

• 센서학회지
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• 제27권2호
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• pp.132-136
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• 2018

We report the development of a room-temperature hydrogen ($H_2$) gas sensor based on carbon nanotubes (CNT) yarn. To detect $H_2$ gas in room temperature, a highly ordered CNT yarn was placed on a substrate from a spin-capable CNT forest, followed by the deposition of a platinum (Pt) layer on surface of the CNT yarn. To examine the effect of the Pt-layer on the response of the CNT sensor, a comparative sensing performance was characterized on both the Pt deposited and non-deposited CNT yarn at room temperature. The Pt-CNT yarn yielded high response, whereas the non-deposited CNT yarn showed negligible response for $H_2$ detection at room temperature. Pt is a reliable and efficient catalyst that can substantially improve the detection of $H_2$ gas by chemical sensitization via a "spillover" effect. It can be efficiently utilized to increase the sensitivity and selectivity as well as to obtain fast response and recovery times.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1489-1515
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• 2022

The number of interconnected real-world devices such as sensors, actuators, and physical devices has increased with the advancement of technology. Due to this advancement, users face difficulties searching for the location of these devices, and the central issue is the findability of Things. In the WoT environment, keyword-based and geospatial searching approaches are used to locate these devices anywhere and on the web interface. A few static methods of indexing and ranking are discussed in the literature, but they are not suitable for finding devices dynamically. The authors have proposed a mechanism for dynamic and efficient searching of the devices in this paper. Indexing and ranking approaches can improve dynamic searching in different ways. The present paper has focused on indexing for improving dynamic searching and has indexed the Things Description in Solr. This paper presents the Things Description according to the model of W3C JSON-LD along with the open-access APIs. Search efficiency can be analyzed with query response timings, and the accuracy of response timings is critical for search results. Therefore, in this paper, the authors have evaluated their approach by analyzing the search query response timings and the accuracy of their search results. This study utilized different indexing approaches such as key-words-based, spatial, and hybrid. Results indicate that response time and accuracy are better with the hybrid approach than with keyword-based and spatial indexing approaches.

• 해양환경안전학회지
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• 제25권4호
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• pp.413-422
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• 2019

해양사고는 항상 인적/물적 피해를 동반한다. 이러한 해양사고가 발생하였을 때 선박의 관리급 해기사가 정확한 지식을 바탕으로 비상 상황에 적절히 대응 한다면 이러한 인적/물적 피해는 최소화 할 수 있을 것이다. 본 연구에서는 해양사고 사례분석을 바탕으로 해양사고 발생 시 부족했던 해기능력 식별, 국제협약에서 요구하는 비상대응 능력을 비교, 선사가 보유하고 있는 다양한 비상대응 매뉴얼 분석 및 설문을 통해 해기사의 비상대응능력 향상을 위한 개선 사항을 제안하였다. 주요 해양사고사례를 통해서 많은 관리급 항해사가 손상복원력, 비손상복원력에 대한 지식의 부재를 식별하였고, 국제협약에서 요구하는 비상대응 해기능력의 경우 일부 축소해서 제공되고 있다는 것을 확인할 수 있었다. 더불어 선사의 비상대응 매뉴얼은 대체로 잘 갖추어져 있으나 실제 비상시 활용 측면에서는 한계가 있다는 것을 식별하였다. 이러한 분석을 바탕으로 선원 및 선사 관계자를 대상으로 설문을 시행하여 국제협약에서 요구하는 비상대응 해기교육의 확대, 시뮬레이터를 활용한 비상상황에 대한 간접경험 기회제공 확대 및 비상 시 효과적이고 효율적인 대응을 위한 지침 또는 매뉴얼의 개발 등을 제안하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(A)
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• pp.305-307
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• 2012

World Wide Web (WWW)의 지속적인 성장으로 인해 Web Service의 Response Time을 수집하는 방식에 관한 연구가 진행되고 있다. 현재 Client Response Time을 수집하는 방식은 sniffer[1] 를 이용한 Agent 방식을 사용하고 있다. 하지만, 기존의 방식은 클라이언트 PC에 설치되어 수집하게 되므로 Agent의 설치가 쉽지 않고, 관리 또한 어려운 문제점을 갖고 있다. 이러한 문제점을 개선하기 위하여, 본 논문에서는 Web Application Server (WAS)[2] 에서의 Dynamic HTML 변경을 통해 Client에 추가적인 Application을 설치하지 않고도 Client의 Response Time을 Collection하는 방식에 대하여 제안하였다. 이를 통해, 사용자 (End-User)에게 추가적인 응용 프로그램을 설치하지 않고도 Dynamic HTML 을 이용하여 Client Response Time을 수집함과 동시에 Server에 Feedback할 수 있다.

• 한국환경복원기술학회지
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• 제2권1호
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• pp.66-71
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• 1999

Main concern is to figure out the growth response of Pinus densiflora to hydrologic conditions in the central Korea. Continuous measurements were carried out with six trees with dendrometers in the Chungbuk National University experimental forest (Wolak-san) during 1995~1996. Surrounding hydrological conditions reflected by the solar radiation, air temperature, precipitation, soil water were included in measurements. Their effects on the biological response of trees was investigated and expressed as response functions. With these response functions, tree growth model was developed. Soil water availability was more related to the tree growth than air temperature. Limited number of biological measurements with dendrometer could permit determination of dynamics of radial tree growth to the hydrological conditions. Tree growth model could be used to check and revise the statistical transfer function of dendrohydrology.

• 한국생산제조학회지
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• 제19권4호
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• pp.582-588
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• 2010

This paper presents the Application of Response Surface Method for Optimal Transfer Conditions of MLCC Alignment System. his paper is composed of two parts: (1) Testing performance verification of MLCC alignment system, compared with manual operation; (2) Applying response surface method to figuring out the optimal transfer conditions of MLCC transfer system. Based on the successfully developed MLCC alignment system, the optimal transfer conditions have been explored by using RSM. The simulations using $ADAMS^{(R)}$ has been performed according to the cube model of CCD. By using $MiniTAB^{(R)}$, we have established the model of response surface based on the simulation results. The optimal conditions resulted from the response optimization tool of $MiniTAB^{(R)}$ has been verified by being assigned to the prototype of MLCC alignment system.