• 한국통신학회논문지
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• 제30권4B호
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• pp.186-191
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• 2005

To provide fairness among different ONUs in EPON, the upstream channel remains idle for some time after OLT receives the buffer status from all ONUs every cycle, which decreases the utilization and increases the delay. To solve this deficiency, we present a new grant scheduling method. The method consists of dividing ONUs into several sets where OLT can schedule ONUs in one set while others will be transmitting their traffic. This method will better utilize the bandwidth of EPON. The numerical results show that the larger the number of ONU sets is the smaller the minimum overhead becomes.

• Journal of Communications and Networks
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• 제17권2호
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• pp.203-209
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• 2015

Although mobile applications are an essential characteristic of wireless sensor networks, most existing media access control (MAC) protocols focus primarily on static networks. In these protocols, fixed periodic neighbor discovery and schedule updating are used to connect and synchronize neighbors to provide successful data transmission; however, they cannot adapt to mobile speed variation and degrade the network performance dramatically. In this paper, we propose a mobile-supporting mechanism for MAC protocols, in which the decision to update the neighbors of a mobile node is made adaptively according to the mobile speed. Analysis and simulation results demonstrate that the mechanism efficiently avoids the disconnection of amobile node from its neighbors and achieves a better performance as compared with fixed periodic neighbor discovery.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2006년도 추계학술발표대회
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• pp.491-494
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• 2006

최근 국내에서도 IT 프로젝트 관리의 중요성이 대두 되고 있으나, 중소규모의 프로젝트를 관리 함에 있어서 PMBOK(Project Management Body Of Knowledge)의 프로젝트 관리 이론과 PERT/CPM(Program Evaluation and Review Technique/Critical Path Method)과 같은 관리 기법들을 이용한 효율적인 프로젝트 평가 및 관리 사례는 많지 않는 실정이다. 철저한 프로젝트 관리를 위해서 소요되는 추가적인 인적 및 시간적 자원에 대한 투자가 현실적으로 어려우며, 평가 기준이나 기법들이 너무 복잡하고 난해한 것이 주된 원인이라 생각된다. 이 논문은 이러한 현실적인 상황을 고려하여, 중소규모의 IT 프로젝트에 적용하기 쉬우면서 효율적으로 활용할 수있는 시간과 인적자원에 대한 일정 시뮬레이션 모델을 통해 프로젝트를 평가하는 정량적 기준을 제공하고 이를 통해 프로젝트의 성공적 완수를 돕는데 의의가 있다.

• 한국정보처리학회논문지
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• 제7권3호
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• pp.862-870
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• 2000

Recently, according to the rapid development of internet and communication technologies, a lot of works based on network techniques have been developed. In relation to this trend, the agent systems that had been studied in the early AI have been being studied greatly in association with the network techniques. This paper present a design model of a secretary agent system in which each secretary agent can manage the schedules of her/his superior, and the descriptions about the implementation of the secretary agent system. In the presented secretary agent system, a database system and a knowledge-based systems are included and cooperated with each secretary agent to provide the ability of manipulating lots of schedule data and making decisions on them. This paper also shows that the presented secretary agent system can behavior like a real secretary through the various superior-secretary-meeting-requester interactions, which is different from the roup scheduling programs or personal scheduling programs.

• 품질경영학회지
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• 제39권2호
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• pp.271-280
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• 2011

In this paper, the relationships between code-share networks and performances in airline industry were analyzed by using Social Network Analysis (SNA). We first analyzed the schedule data from OAG (Official Airline Guide) to obtain core-share information of airline industries. SNA was, then, applied to the code-share information. Finally, statistical analysis was conducted to analyze the relationships between code-share social networks and performances. The result shows that the size and out-degree centrality have relatively significant effects on the performance of airline industries, while in-degree and betweenness centrality has less significant effects.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.2781-2798
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• 2019

Thanks to internet, as one of indispensable parts of our lives, many devices that we use in our daily lives like TV, air conditioner, refrigerator, washing machine, can be monitored and controlled remotely by becoming more intelligent via Internet of Things (IoT) technology. Smart Home applications as one of the elements of smart cities, are individually the most demanded application without question. In this study, Smart Energy Management (SEM) system, based on NodeMCU and Android, has been designed for SEM, which is a part of the smart home application. With this system, household energy consumption can be monitored in real time, as well as having the ability to record the data comprising of operation times and energy consumption information for each device. Additionally, it is ensured to meet the energy needs on a maximized level possible, during the hours when the energy costs are lower owing to the SEM system. The Android interface provides the users with the opportunity to monitor and change their electricity consumption habits in order to optimize the energy efficiency, along with the opportunity to draw up of a daily and weekly schedule.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.534-537
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• 2009

센서 네트워크에서 클러스터링은 클러스터 헤드 노드가 일반 노드의 데이터를 모아 싱크로 전송함으로써 노드 간의 통신의 양을 줄이게 하고 일반 노드의 스케쥴을 조정함으로써 노드의 슬립타임을 연장하게 한다. 제안하는 CHS(Cluster Head Self-election) 알고리즘은 노드 자신만의 변수 즉, 자신의 초기 에너지 및 현재 에너지, 클러스터 헤드에 의해 병합된 클러스터 내 노드들의 데이터가 싱크로 전송되는 각 라운드, 노드 자신이 클러스터 헤드로 선출된 수를 이용하여 확률적인 방법으로 클러스터 헤드를 스스로 선출하여 에너지가 제한되는 센서 네트워크의 수명을 연장하였다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1548-1552
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• 2009

In the construction industry, IT has been an alternative for the enhancement of productivity and technical advances through a paradigm shift. While it has been recognized that the IT system will have a substantial influence on the industry, a quantitative valuation has been very limited. This paper has chosen EVMS (Earned Value Management System), which supports the integrated management of cost and schedule by utilizing IT tools, and which is the largest trend in the construction IT industry in Korea, in order to suggest an analysis model for the valuation of IT. The CVM (Contingent Valuation Method) is used to quantitatively measure intangible value of IT application. Then, a valuation and analysis model were suggested for the quantitative valuation of the effect of IT adoption. In terms of willingness to pay for EVMS, the expected benefits from the adoption of EVMS were US$ 584.52 per man annually. This research should be helpful for construction companies evaluating their investment to Project Management Information System.

• Journal of Electrical Engineering and information Science
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• 제1권1호
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• pp.118-128
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• 1996

In safety critical hard real-time systems, a timing fault may yield catastrophic results. In order to eliminate the timing faults from the fast responsive real-time control systems, it is necessary to schedule a code based on high precision timing analysis. Further, the schedulability enhancement by having multiple processors is of wide spread interest. However, although an instruction level parallel processing is quite effective to improve the schedulability of such a system, none of the real-time applications employ instruction level parallel scheduling techniques because most of the real-time scheduling models have not been designed for fine-grain execution. In this paper, we present a timing constraint model specifying high precision timing constraints, and a practical approach for constructing static schedules for a VLIW execution model. The new model and analysis can guarantee timing accuracy to within a single machine clock cycle.

• 한국도서관정보학회지
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• 제44권1호
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• pp.143-175
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• 2013

본 연구에서는 지식정보사회의 능력있는 전문사서 양성을 위한 주요 전공과목의 교과내용을 개발, 제안하고자 하였다. 이를 위해 국내 39개 문헌정보학과에 개설된 핵심 전공과목의 강의계획서를 조사 분석하여 국내 문헌정보학 교육내용의 현황을 파악하였다. 주요 교과목의 교과내용인 강의계획서 개발대상과목은 2011년 선행연구에서 제안된 핵심 교과목으로, "문헌정보학개론", "정보조직론", "정보서비스론", "도서관경영론", "정보검색론", "도서관실습" 6개 과목이다. 강의계획서는 강의개요(목표 및 목적), 교수법, 평가방법, 주요 교재, 15주 또는 16주의 강의일정 및 내용(강의계획서)을 포함한다.