• 한국IT서비스학회지
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• 제15권3호
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• pp.195-209
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• 2016

IoT (Internet of Things) is a collective term referring to application services that provide information through sensors/devices connected to the internet. The real world application of IoT is expanding fast along with growing number of sensors/devices. However, since IoT application relies on vertical combination of sensors/devices networks, information sharing within IoT services remains unresolved challenge. Consequently, IoT sensors/devices demand high construction and maintenance costs, rendering the creation of new IoT services potentially expensive. One solution is to launch an IoT open market for information sharing similar to that of App Store for smart-phones. Doing so will efficiently allow novel IoT services to emerge across various industries, because developers can purchase licenses to access IoT resources directly via an open market. Sharing IoT resource information through an open market will create an echo-system conducive for easy utilization of resources and communication between IoT service providers, resource owners, and developers. This paper proposes the new business model of IoT open market for information sharing, and the requirements for ensuring security and standardization of open markets.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.1129-1132
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• 1992

This paper proposes a high frequency resonant inverter consisting of equivalent half bridge model using MOSFET. In this paper time-sharing control method is applied. as a result the output frequency is two times as high as switching frequency of device, and average current of device is incresed because of decreasing switching loss.

• Journal of Advanced Marine Engineering and Technology
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• 제24권3호
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• pp.106-112
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• 2000

Since the oil crisis, we have been concerned about the energy saving techniques of electric generating systems. As a part of the effort to save energy, automatic electric load sharing device was developed. Usually, ship's electric generating system consists of two or three sets of generator. And, electric generating system is operated as single or parallel operation mode according to the demanded electric power. Therefore, it is important to investigate generators operating mode for the supply of required electric power in the ship in order to decrease the operating cost. So, this paper suggests the method to solve the optimal electric load distribution problem by dynamic programming. And, this thesis indicates that the proposed method is superior to the lagrange multiplier's method in obtaining optimal load distribution solution in the ship's electric generating system.

• 한국실내디자인학회논문집
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• 제26권4호
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• pp.75-83
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• 2017

The cultural tendency based on sharing and cooperation, which has recently been a hot issue, accelerates throughout the world. This study began with a perception that a sharing culture is inherent in urban public spaces. This study aims to conduct a theoretical study of the sharing culture and to analyze the characteristics of the design composition of public spaces. This study selected squares in 16 European cities as cases for analysis. The results are summarized as follows:1)To analyze the design characteristics of public spaces in which a sharing culture is inherent, this study drew the shape and type of planes and sharing elements such as accessibility, symbolism and activity with the squares in the cases. 2)The shape of planes in the squares in the cases has been formed in close relations with the historic meaning and events of the area and the process of the construction of buildings surrounding the square. The squares in the cases were classified into seven plane types, and these squares have developmentally contributed to the formation of a sharing culture as a place for free participation and communication concerning social issues. 3)In the squares in the cases, the weight of road-centered access appears high, and in terms of the construction of human-friendly / environment-friendly infrastructure in the city or judging from the trend of the recent increase of pedestrian-centered plans for public space, it is judged that approaches with a high utilization rate of sidewalk or public transportation would be desirable. 4)Symbolic elements of the square become a device by which citizens can share the historic symbolism, along with artistic inspiration. In addition, by serving as an observatory from which people can take a view of the landscape of the city, it allows visual sharing of the entire city as well as the square. 5)A square is common pool resources in the community, and it is necessary to vitalize that in a direction of increasing the possibility of sharing, through the characteristics and methods of the composition of public design.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2235-2239
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• 2003

The aim of this research is to study and develop enabling technologies for home healthcare device with ubiquitous network. The motivation of this paper is to enable healthcare in home, to development the device for smart home health care. To achieve the aim, we must develop the prototype platform based on home gateways, distributed context user interface based on UPnP and support for information sharing with high speed power line communication and mobile infra-structures. And IPv6 is the base technology of this platform. In this paper, we concern that physical health, mental health and medical emergencies is all of home healthcare. With the smart device, we evaluate the connectivity, automatic information extraction and private data exchange and event driven message. The result of this paper is demonstration of smart device for ubiquitous communication in a healthcare application such as patient monitoring device and several information services. In conclusion, home healthcare will support more healthy and easy living for a human.

• 한국컴퓨터정보학회논문지
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• 제16권9호
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• pp.19-26
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• 2011

최근 스마트 폰과 같은 다양한 모바일 장치들의 개발과 함께 사용자는 자신의 모바일 단말을 이용하여 개인화된 서비스를 제공받기를 원한다. 이러한 요구사항을 만족하기 위하여 모바일 장치들은 많은 기능을 제공해야하지만 모바일 장치가 소형화됨에 따라 작은 디스플레이 장치, 제한적인 입력 장치 그리고 부족한 파워와 같은 자원 제약성을 갖는다. 본논문은이러한자원의제약성을해결하고사용자에게개인화된서비스를제공하기위하여유비쿼터스환경에서 컴퓨팅 자원을 공유하여 사용자에게 서비스를 제공하기 위한 환경을 제안한다. 또한 다양한 자원들 가운데 사용자의 상황과 개인 선호도를 기반으로 최적의 자원을 추천하기 위한 방법을 제안한다. 이러한 자원 추천을 위하여 본 논문에서는 사용자의 사용 이력으로부터 행동 유형을 분석하고 이를 기반으로 개인화된 자원을 추천하기위한 방법을 사용한다. 또한 논문은 제안한 방법을 구현하고 만족도를 평가하여 유효성을 보인다.

• Journal of Multimedia Information System
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• 제3권4호
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• pp.135-140
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• 2016

To improve the throughput of Device-to-Device (D2D) communication, we focus on the scenario where D2D pair can reuse multi-channel of cellular communication. However, as sharing same channel with cellular communication can cause interference between D2D communication and cellular communication, a proper interference management is needed. In this paper, we propose interference-based channel allocation to select the channels to be used by D2D communication and a solution from game theory perspective to optimize the D2D communication throughput under multi-channel as well as guarantee the interference from it to cellular network. The simulation results verify the stability of the proposed method.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1415-1423
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• 2016

Interference in device-to-device (D2D) communication underlaying cellular network needs to be elaborately investigated because of channel sharing. The objective is to improve the quality of D2D communications while maintaining high performance for cellular users. In this paper, we solve the above problem by jointly considering channel allocation and power control using coalition formation game. Our cooperative game theoric approach allows to enhance network-wide performance. We design a merge-and-split algorithm to deal with the complexity of the combinatorial structure in coalition formation problem. The analytical and numerical results show that our algorithm converges to a stable point which achieves high network performance.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.323-324
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• 2021

This study is to develop a non-contact construction project management solution that can reduce cost and construction period through on-site information sharing, minimizing contact with others by COVID19, and improving the productivity of the construction industry. Decisions, checklists, and execution rates of construction costs can be checked with smart devices through sharing on-site photos and videos, exchanging opinions. Details and checklist data stored on cloud servers of sites that apply non-face-to-face construction project management solutions will be used as data for analyzing amounts and construction periods depending on the size of the construction. Real-time field information sharing will reduce expected problems and waste factors, expand communication channels with users to prevent or minimize construction disputes and claims, and contribute to the expansion and growth of new research industry markets in construction technology.

• 대한화학회지
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• 제68권2호
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• pp.93-106
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• 2024

이 연구에서는 증강현실을 활용한 소집단 학습에서 도구 공유 정도에 따른 학생들의 현존감, 몰입, 상황흥미의 차이를 조사하였다. 중학교 2학년 학생 84명이 각각 4명씩 소집단을 구성하여 연구에 참여하였다. 각 소집단을 마커와 스마트폰의 공유 여부에 따라 공유 환경(마커와 스마트폰 공유 사용), 혼합 환경(마커 공유 및 스마트폰 개별 사용), 개별 환경(마커와 스마트폰 개별 사용)으로 무선 배치하였다. '물질의 특성' 단원에서 증강현실을 활용한 소집단 학습을 3차시 동안 실시하였다. 종속 변인에 대한 일원 분산 분석 결과, 공유 환경 대비 혼합 환경에서는 현존감과 상황흥미가, 개별 환경에서는 몰입과 상황흥미가 각각 통계적으로 유의하게 더 높았다. 각 종속 변인의 하위요소에 대한 다변량 분산 분석 결과, 현존감에서는 실제성, 몰입에서는 선행요소와 경험요소, 상황흥미에서는 순간적 즐거움, 새로움, 전체 흥미에서 각각 통계적으로 유의한 차이가 있었다. 면담 및 수업 관찰 결과, 공유 환경과 개별 환경의 학생들은 증강현실을 활용할 때 개별적으로 스마트폰을 사용하는 경향이 있었지만 혼합 환경의 학생들은 스마트폰을 협력적으로 사용하며 더 활발하게 상호작용하는 경향이 나타났다. 연구 결과를 바탕으로 도구 사용 환경의 측면에서 증강현실을 활용한 소집단 학습의 효과를 높이기 위한 방안을 제안하였다.