• 전자통신동향분석
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• 제34권4호
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• pp.117-128
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• 2019

As companies use increasing amounts of data more and more, people are more concerned about protecting their privacy. Many researches studies have been conducted with a to securely view of manage managing and share sharing private information securely using the Bblockchain technology. These studies have suggested a Bblockchain-based approaches to provide efficiency, scalability, data ownership, and systematic data lifecycles that were are the limitations of lacking in traditional access controls. More Sspecifically, these studies have introduced a new access control models, distributed hash tables, trusted execution environments, and hierarchical ID-based cryptographic mechanisms to provide reliable access control even in complex environments such as IoT Internet of Things. In this paperstudy, we present the criteria to for classifying the functional characteristics of the Bblockchain-based access control methods and derive the differentiateion between of each the several methods.

• International Journal of Internet, Broadcasting and Communication
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• 제11권1호
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• pp.17-26
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• 2019

The Constrained Application Protocol (CoAP) is a specialized web transfer protocol proposed by the IETF for use in IoT environments. CoAP was designed as a lightweight machine-to-machine protocol for resource constrained environments. Due to the strength of low overhead, the number of CoAP devices is expected to rise rapidly. When CoAP runs over UDP for wireless sensor networks, CoAP needs to support congestion control mechanisms. Since the default CoAP defines a minimal mechanism for congestion control, several schemes to improve the mechanism have been proposed. To keep CoAP lightweight, the majority of the schemes have been focused mainly on how to measure RTT accurately and how to set RTO adaptively according to network conditions, but other approaches such as rate-based congestion control were proposed more recently. In this paper, we survey the literature on congestion control for CoAP and discuss the future research directions.

• ETRI Journal
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• 제43권4호
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• pp.594-602
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• 2021

Recently, quantitative and repetitive inspections of the old urban area were conducted because many structures exceed their designed lifetime. The health of a building can be validated from the condition of the outer wall, while the slant angle of the wall widely serves as an indicator of urban regeneration projects. Mostly, the inspector directly measures the inclination of the wall or partially uses 3D point measurements using a static light detection and ranging (LiDAR). These approaches are costly, time-consuming, and only limited space can be measured. Therefore, we propose a mobile mapping system and automatic slant map generation algorithm, configured to capture urban environments online. Additionally, we use the LiDAR-inertial mapping algorithm to construct raw point clouds with gravity information. The proposed method extracts walls from raw point clouds and measures the slant angle of walls accurately. The generated slant angle map is evaluated in indoor and outdoor environments, and the accuracy is compared with real tiltmeter measurements.

• 전기학회논문지
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• 제60권9호
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• pp.1668-1673
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• 2011

Recent power industries are to be progressed as moving into horizontal markets and expanding of competitive systems through promoting SmartGrid. In these environments, the information on power consumers leads to establish a part of power markets through active and real-time participations instead of participating it as a passive manner presented by a vertical integration. Also, such information should be established as a way that effectively reflects changes and market behaviors occurred in power market participants. Therefore, in this study, a method that develops consumer information models, performs integrated managements, implements registration and distribution, and forms integrated management centers is presented to commonly use the consumer information according to the change in the environment of power industries.

• 한국정보시스템학회지:정보시스템연구
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• 제17권3호
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• pp.153-174
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• 2008

Mobile commerce is defined as any direct or indirect transaction conducted and facilitated through a wireless telecommunication network such as payment, ticketing, auction and mobile banking. Despite the importance of mobile commerce, there have not been so many academic studies on the unique characteristics of mobile commerce environments. In this study, our research model is developed based on TAM(Technology Acceptance Model) to investigate the user's technology acceptance process in mobile commerce environment. The factors, such as ubiquity, compatibility, perceived usefulness, perceived ease of use, cost, security, attitude and behavior intention for mobile commerce were selected from pier study in information systems area. The data for empirical analysis of the research model is collected online-questionnaire of 167 mobile commerce users in South Korea. The hypotheses were analyzed using SPSS 15.0 and AMOS 7.0. The results of our study show that: (1) compatibility, perceived usefulness and security had influences on the attitude whereas perceived ease of use and cost did not have any significant impact on the attitude, (2) compatibility influenced perceived usefulness whereas perceived ease of use did not, and finally (3) ubiquity, perceived usefulness and attitude had considerable influences on intention for mobile commerce. Therefore, practitioners should focus on enhancing security, quality of contents and services as well as offering what mobile commerce users want. The results of this study may useful for academicians and practitioners alike.

• 정보처리학회논문지D
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• 제10D권4호
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• pp.613-620
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• 2003

RPC는 분산 시스템에서 가장 많이 활용되고 있는 통신 메커니즘 중의 하나이다. 본 연구는 현재 많이 활용되고 있는 RPC 프로토콜 중, XML-RPC를 이용하여 분산 환경하에서 데이터베이스를 활용하기 위한 단일화된 인터페이스 설계에 목적을 둔다. 기존의 RDB를 이용한 프로그램에 있어서 데이터베이스의 접근은 프로그래밍 언어, 플랫폼, 사용 데이터베이스의 종류 등에 따라서 특정한 API를 사용해야만 하는 프로그래밍 형태를 취했으나, XML-RPC 프로토콜을 이용하여 구현한 미들웨어를 둠으로써 데이터베이스 접근 인터페이스를 단일화하여 특정 언어와 환경에서 여러 상이한 데이터베이스에 대한 접근 및 조작을 용이하고 편리하게 하였다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권1호
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• pp.45-49
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• 2010

RTLS(Real Time Locating Systems)는 실시간으로 대상들의 위치를 추적하고 파악하는데 사용된다. RTLS는 태그, 리더, 엔진 등으로 구성되고, 다양한 환경에 적용된다. RTLS 의 문제점 중 하나는 환경에 따라 리더를 설치하는데 제약사항이 발생할 수 있다는 것이다. 이러한 환경에서는 이동형 리더를 사용할 수 있는 기술을 개발할 필요가 있다. 이동형 리더가 많아지면 전체 리더 개수도 늘어난다. 그리고 그 중에서 일부 유용한 리더들만 선택하여 이용한다. 선택된 리더들은 RTLS의 성능에 영향을 미친다. 이 논문에서는 convex hull 알고리즘을 사용하여 좋은 리더를 선택하는 기술을 소개한다. 성능 평가 결과, 위치오차가 작고, 네트워크 오버헤드를 줄여 RTLS의 성능이 개선되었음을 보여준다.

• 대한임베디드공학회논문지
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• 제4권3호
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• pp.139-147
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• 2009

This paper proposed the context awareness reasoning system to provide the personalized services dynamically in a ubiquitous mobile environments. The proposed system is designed to provide the personalized services to mobile users and consists of the context aggregator and the knowledge manager. The context aggregator can collect information from networks through Open API Gateway as well as sensors in a various ubiquitous environment. And it can also extract the place types through the geocoding and the social address domain ontology. The knowledge manager is the core component to provide the personalized services, and consists of activity reasoner, user pattern learner and service recommender to provide the services predict by extracting the optimized service from user situations. Activity reasoner uses the ontology reasoning and user pattern learner learns with previous service usage history and contexts. And to design service recommender easy to flexibly apply in dynamic environments, service recommender recommends service in the only use of current accessible contexts. Finally, we evaluate the learner and recommender of proposed system by simulation.

• 한국도서관정보학회지
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• 제35권2호
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• pp.155-173
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• 2004

이 연구는 21세기 지식기반사회에서 우리나라 전문도서관ㆍ정보센터가 서비스를 향상하고 조직의 경쟁력을 강화하기 위한 방안을 모색하였다. 이를 위해 우선 전문도서관ㆍ정보센터의 특성을 살펴보고 현재 전문도서관ㆍ정보센터가 처한 경쟁환경을 진단하였다. 다음으로 지식경영과 경쟁정보의 관점에서 전문도서관ㆍ정보센터의 경영전략을 모색하였다 나아가 우리 사회의 전문도서관ㆍ정보센터 현실에서 지식경영과 경쟁정보를 활용하기 위한 전략을 제시하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제15권4호
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• pp.73-98
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• 2006

The purpose of this study was to verify and analyze the factors that influence the acceptance intention of u-Commerce users under ubiquitous computing environments. To accomplish this, the Technology Acceptance Model(TAM) of Davis(1989), which has widely been cited in new technologies such as information technology(IT) and information systems(IS) studies was used to develop the research model. First of all, personal characteristics affecting the acceptance intention of u-Commerce were identified as individual variables through literature review. Utilizing the use of the individual variables and the TAM model, the u-Commerce acceptance intention model was established. The research findings indicated that IT acceptance forms and frequencies in IT use did not have a significant impact on perceived usefulness and perceived ease of use of u-Commerce. It was also found that the perceived usefulness proposed in the u-Commerce acceptance model influenced the perceived usefulness. Both ease of use and usefulness were identified to influence attitude for use. Finally, usefulness and attitude for use also positively influenced acceptance intention. The contribution of this study was the examination of the factors affecting acceptance intention of users in u-Commerce and the verification of the usefulness of the TAM model in describing the acceptance of u-Commerce users using structure acceptance model. Furthermore, this study has empirically analyzed how personal characteristics widely used in the study of acceptance of IT can influence the acceptance of u-Commerce.