• 한국정보통신학회논문지
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• 제3권4호
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• pp.747-754
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• 1999

Mobile Agent는 네트워크 환경에서 관리자의 작업을 자율적으로 대신 수행하는 이동이 가능한 소프트웨어 프로그램으로 현재 여러 분야에서 응용되어지고 있는 기술이다. 본 논문에서는 분산환경에서 mobile agent 기술을 이용한 네트워크 관리 구조를 제안하였다. Mobile agent를 생성한 후 네이밍 서비스에 의해 분산 객체인 SNMP 대리자 프록시를 찾아내고 이후 mobile agent와 프록시 사이의 통신을 통해 필요한 관리정보를 획득하여 관리 시스템으로 전달하게 하였다. 분산환경에서 투명성 제공을 위해 CORBA를 기반으로 하였다. 또한 SNMP 대리자를 위한 프록시를 두어 SNMP 대리자와 CORBA 객체인 mobile agent 간의 통신을 가능하게 하였다. 제안된 구조에서 mobile agent는 자동화된 관리 기능 수행이 가능하며 새로운 관리 기능 추가 및 변경을 용이하게 하므로 효율적인 관리 방식을 제공함을 알 수 있었다.

• 품질경영학회지
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• 제50권3호
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• pp.617-634
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• 2022

Purpose: This paper introduces Pohang University of Science Technology (POSTECH) advanced metering infrastructure (AMI) and Open Innovation Big Data Center (OIBC) platform and analysis results of electricity consumption data collected via the AMI in POSTECH campus. Methods: We installed 248 sensors in seven buildings at POSTECH for the AMI and collected electricity consumption data from the buildings. To identify the amounts and trends of electricity consumption of the seven buildings, electricity consumption data collected from March to June 2019 were analyzed. In addition, this study compared the differences between the amounts and trends of electricity consumption of the seven buildings before and after the COVID-19 outbreak by using electricity consumption data collected from March to June 2019 and 2020. Results: Users can monitor, visualize, and download electricity consumption data collected via the AMI on the OIBC platform. The analysis results show that the seven buildings consume different amounts of electricity and have different consumption trends. In addition, the amounts of most buildings were significantly reduced after the COVID-19 outbreak. Conclusion: POSTECH AMI and OIBC platform can be a good reference for other universities that prepare their own microgrid. The analysis results provides a proof that POSTECH needs to establish customized strategies on reducing electricity for each building. Such results would be useful for energy-efficient operation and preparation of unusual energy consumptions due to unexpected situations like the COVID-19 pandemic.

• Journal of Communications and Networks
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• 제6권4호
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• pp.295-306
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• 2004

In this paper, a novel air-interface is presented for Fleet-Net1, a self-organizing network for inter-vehicle and vehicle-toroadsidecommunication. The air-interface is based upon the lowchip-rate version of UMTS/TDD. To adapt the cellular UMTS standard to an air-interface for ad hoc networks, changes of the physical layer, medium access control sub-layer and radio resource management are required. An overview of the required modifications is given here. Particularly, a decentralized synchronization mechanism is presented and analyzed by means of simulations. Furthermore, changes for the medium access control are explained in detail, which allow for an efficient operation in partly meshed networks and prioritization. Performance results of the overall system considering throughput and delay are derived by means of analytical evaluations and event-driven simulations. Based on realistic mobility models, it is shown that the presented solution provides a robust communication platform even in vehicular environments. The proposed air-interface is a cost-effective solution not only for inter-vehicle communication, but also for ad hoc networking in general, benefiting from the mass-market of UMTS.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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• pp.112-114
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• 2005

In today's hyper-competitive business environment, Radio Frequency Identification (RFID) technology is expected to enhance the operation efficiency of supplying chain management in both manufactures and retail industries. However, the widespread deployment of RFID tags may create new threats to user privacy, due to the powerful tracking capability of the tags. Many authentication protocols for RFID have been proposed. They are helpful preventing passersby being scanned to determine what articles they are carrying. However, most of them would not prevent the bigger physical tracking problem of RFID, especially when being tracked by the 'constellation' of products they carry. We proposed this RFID scheme to prevent these tracking problems.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2077-2081
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• 2011

Recently the train indusrty come to the fore because of Punctual, eco-friendly transportation system and becoming the main transportation. The construction plans for the trian depot for train's maintenance and storage increase constantly. For past few years, there were many construction plans, Bubal train depot, Gwangju train depot, Duckha train depot. Proper track distribution plan is important to carry out the design of railway depot for efficient maintenance operation and train storage. Through the proper design of track distribution plan, we can shorten the moving time, train movement distance, waiting time in train depot. In this paper, the verification of the track distribution plan's efficiency and appropriateness for railway depot as Bubal train depot's plan is studied and analyzed with the train depot management simulation program-Posrail(v1.0).

• 수산해양교육연구
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• 제26권2호
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• pp.444-454
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• 2014

The range of optimization problem in aquaculture is very wide, resulting from the range of species, mode of operation. Quite a few studies focus marine net-cages, but studies on land based culture farm are few or no. This paper considers a allocation problem to meet production planning in land based aquaculture system. A water pool allocation model in land based aquaculture system was developed. The solution finds the value of decision variable to minimize yearly production costs that sums up the water pool usage cost and sorting cost. The model inputs were (1) the fish growth rate (2) critical standing corp (3) number of water pool (4) number of fish. The model outputs were (5) number of water pool in growing phase (6) cost of cultivation (6) optimal facility allocation(number of water pool for each growing phase). To solve the problem, an efficient heuristic algorithm based on a greedy manner is developed. Branch and bound and heuristic is evaluated through numerical examples.

• 한국신뢰성학회지:신뢰성응용연구
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• 제15권4호
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• pp.276-281
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• 2015

Purpose : The purpose of this study is to propose that domestic rail must the work to be done in the RCM system and railway operators are to present a direction to establish the efficient and systematic system based on this. Methods : In recent years, domestic railway accidents has decreased year rapidly every year. In particular, suicidal ideation was greater than 50% of the accidents is showing a larger decrease in the influence of the screen-door construction. However, the train delay has been maintained without major changes since 2010. The most important cause of the delay operation is a vehicle breakdown. This fact demonstrates that effective maintenance of the most important activities in the railway accident prevention activities. So we have to build a RCM system in which the characteristics of the domestic railway accident. Conclusion : We proposed what is necessary functionality and the function requires a railway operators in RCM railway systeml.

• 한국컴퓨터정보학회논문지
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• 제6권2호
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• pp.27-33
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• 2001

본 논문에서는 ARIES를 기반으로 하는 ARIES/SR이라 명명된 간단하고 효과적인 회복 기법을 제안한다. ARIES는 거래가 완료되었거나 완료되지 않았거나 관계없이 모든 거래에 의해 수행된 갱신 연산에 대해 재수행을 수행한다. 따라서 시스템 고장 후 회복시 큰 부담이 존재한다. 따라서 이러한 부담을 줄이기 위해 ARIES/SR이란 새로운 회복기법을 제안한다. 이 기법에서는 재수행 연산을 줄이기 위해 완료된 거래에 대해서만 재수행 연산을 수행한다. 또한 미 완료된 거래에 대해 조건적인 철회를 수행함으로써 회복에 필요한 연산의 횟수를 줄일 수 있는 방법이다.

• Asia pacific journal of information systems
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• 제7권3호
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• pp.109-124
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• 1997

Pricing information services, where congestion can threaten the efficient operation of information systems, has been studied in economics and information systems literature, Recent explosion of the Internet ana proliferation of multimedia content over the Internet have rekindled the research interest in designing pricing schedules for differentiated information services, In order for the information system to effectively serve users having heterogeneous needs, pricing rules for discriminated services should be considered. At the same time, when individual users' interest does not align with that of the organization that individual users belong to, organization-wide pricing policy should be devised to improve the value of the services rendered by the system. This paper, using a priority queuing model, addresses the need for such on incentive-compatible pricing for different information services.

• 대한가정학회지
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• 제48권9호
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• pp.113-123
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• 2010

This study describes the beginning and further development of a collection web-based materials for an efficient approach to culinary practice education. A database was created using a five-step process of analysis, design, development, operation and evaluation. The menu for the web-based culinary practice educational materials included cooking basics, the real status of cooking, cooking related knowledge, performance evaluation, a data room and a bulletin board. As at 30 July, 2010, the datadase of educational materials, contained a total of 571 items. These comprised 139 cooking pictures, 33 recipes, 22 cooking videos, 74 cooking animations, 57 collections of basic knowledge, 14 evaluation reports, 21 supplementary textbooks, and 211 sets of other related information. The webbased materials are adequate for culinary education purposes, and their use is expected to be very highly valued.