• 대한산업공학회지
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• 제43권1호
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• pp.1-11
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• 2017

Stochastic resource-constrained project scheduling problem is an extension of resource-constrained project scheduling problem such that activity duration has stochastic nature. In real situation where activity duration is not known until the activity is finished, open-loop based static policies such as activity-based policy and priority-based policy will not well cope with duration variability. Then, a dynamic policy based on closed-loop decision making will be regarded as an alternative toward achievement of minimal makespan. In this study, a dynamic policy designed to select activities to start at each decision time point is illustrated. The performance of static and dynamic policies based on variable neighborhood search is evaluated under the discrete-event simulation environment. Experiments with J120 sets in PSPLIB and several probability distributions of activity duration show that the dynamic policy is superior to static policies. Even when the variability is high, the dynamic policy provides stable and good solutions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.100-105
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• 1990

Associated with the protection and control functions in the substations, a new network scheme based on the IEEE 802.4 is proposed in this paper. This network is designed for supporting 3 data classes: 1st, it includes the highly time-critical data for the fault detection function. 2nd, routine data with a period is to served for monitoring the power status. Finally, it contains the control data which is used for reporting an event about protection or tuning some values related with power status. The way to allocate target_token_rotation timer is provided to guarantee the protection and control activities in the suggested network for the substation.

• Asia pacific journal of information systems
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• 제11권3호
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• pp.185-208
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• 2001

A growing number of firms are competitively entering into e-business because they see the high potential of e-business growth as an opportunity. The positive expectation of e-business market leads most firms to go into e-business, but it is not clarified what kinds of benefits firms gain through e-business. In this paper, we examine whether firms' economic benefits are related to e-business activities. For this purpose, we employ event study methodology and assess the cumulative abnormal returns for 782 e-business initiatives made by firms listed in Korean capital markets. The well-known "Dot Com Effect" is empirically verified through this study. The results of this study indicate that the e-business potential is highly evaluated in the capital market, and e-business firms are expected to create significant benefits in the future period.

• 정보관리연구
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• 제35권2호
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• pp.107-130
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• 2004

MPEG-21은 상호운용성이 확보되고 저작권이 보호되는 방법으로 디지털 콘텐츠가 생성, 배포, 소비될 수 있도록 하기 위한 개방형 표준 프레임워크이다. 이 글은 DRM 기술을 중심으로 MPEG-21의 각 분야별-거래와 배포의 기본단위인 디지털 아이템 선언(DID), 디지털 아이템 식별(DII), 저작권 관리 및 보호(IPMP), 권리데이터사전(RDD), 권리표현언어(REL), 영구연결기술(PAT), 이벤트 리포팅(ER)-기술 표준화의 개념과 내용을 살펴본다.

• 천문학회보
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• 제41권1호
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• pp.61.1-61.1
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• 2016

As a new way to explore the universe, astronomers are now performing time-domain astronomy by surveying the universe looking for new transient phenomena and taking movies of the universe with telescopes. Large-area, time-series survey of astronomical objects are uncovering many interesting, fast-changing objects that have now been poorly understood before, such as GRBs, tidal disruption phenomena, and new types of supernova. In order to characterize these new, exciting events, it is very critical to perform follow-up observations, and 1-2m telescopes can effectively contribute to such efforts. Since 2007, our group has been performing follow-up observations of gamma-ray bursts (GRBs) and interesting transients using BOAO and other KASI facilities. Here, we present results from several key transient studies that were done by using BOAO: (1) tidal disruption event Swift J1644+57; (2) SN 2011fe that occurred in M101; and (3) several GRB events. These study demonstrates the usefulness of BOAO as a powerful transient follow-up facility. Finally, we will discuss how BOAO research activities can possibly be bolstered in this newly emerging field of astronomy.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.123-124
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• 2015

The project participants make use of floats for their benefits. The owner may consume floats in an event of issuing change order(s) and may avoid the risk factors attributed by them; the contractor may reduce activities' costs by substituting the activity with alternative construction method and by leveling the resources, hence consuming floats. There are a lot of disputes and claims involved in the float ownership issue. The ownership of floats should be stipulated in the contract stage. To alleviate these disputes and claims, it is commendable to develop a computational method that quantifies the float value. This paper presents the method that computes the values of total floats which changes over the project life span. The system calculates CPM, compute the ratio of area of banana curve which is enclosed by earliest start curve and latest start-curve.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.779-782
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• 2008

During the dry periods, many types of pollutant are accumulating on the paved surface by vehicle activities and accumulated various pollutants are inflowing to the near watershed areas for the rainfall periods. Also, the metals, toxic chemicals and sediments originated from bridges could be strongly influenced to the watershed areas during the runoff. The result shows that the EMC ranges for 95% confidence intervals in a bridge land use are $10.12\sim128.09mg/L$ for TSS, $6.07\sim21.15mg/L$ for BOD, $2.10\sim6.70mg/L$ for TN and $0.06\sim0.85mg/L$ for TP.

• 한국컴퓨터정보학회논문지
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• 제24권9호
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• pp.29-34
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• 2019

In Recently, as the interest in health has increased and the spread of smart phones has become common, the development of smart health care related contents has been active. In this paper, we introduce the design, implementation and effects of game-based content that can make walking exercise fun in the Internet of Things environment. This content calculates the consumed calories by walking the stairs with the Beacon installed, and incorporates games to encourage continuous fun activities. It also provides event functions that enable on-off-line coordination. The goal of this content is to enable busy modern people to exercise lightly, funly, and constantly in the surrounding activity space. The effect of this content has been confirmed through the review of many users participating in offline events. This content is expected to be able to converge with various types of healthcare systems with the expansion of the application space.

• Journal of Positioning, Navigation, and Timing
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• 제11권1호
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• pp.51-58
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• 2022

Korea Augmentation Satellite System (KASS) is a Satellite Based Augmentation System (SBAS) system under development in South Korea and aims to provide air navigation services after 2023. In order to provide reliable service, detailed design for the operation of this system is required. This paper proposes a detailed operation-based designs based on mission, architecture, operation definition of the system. For the stable operation of the system, an operation organization was designed and operation activities were classified in consideration of the architecture and function of the system. Detailed operation procedures were designed according to this classification and operation procedures related to the command and configuration of subsystem were verified on the Integration, Verification and Qualification (IVQ) platform for integrated testing and verification. The proposed operation concepts and procedures will be continuously confirmed and verified during verification, qualification and service preparation, and will be updated event after official KASS service.

• 한국군사과학기술학회지
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• 제26권2호
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• pp.179-187
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• 2023

APT cyber attacks have been a problem for over a past decade, but still remain a challenge today as attackers use more sophisticated techniques and the number of objects to be protected increases. 'Cyberattack Tracing System' allows analysts to find undetected attack codes that penetrated and hid in enterprises, and to investigate their lateral movement propagation activities. The enterprise is characterized by multiple networks and mass hosts (PCs/servers). This paper presents a data processing procedure that collects event data, generates a temporally and spatially extended provenance graph and cyberattack tracing paths. In each data process procedure phases, system design considerations are suggested. With reflecting the data processing procedure and the characteristics of enterprise environment, an operational architecture for CyberAttack Tracing System is presented. The operational architecture will be lead to the detailed design of the system.