• 정보처리학회논문지B
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• 제11B권5호
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• pp.611-618
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• 2004

본 논문에서는 인터넷상의 대용량 자료에서 원하는 정보를 검색하기 위한 지원 기능으로서 분산 객체지향 데이타베이스에서 클래스를 분할하여 여러 사이트에 분산시키는 기법에 관하여 설계 및 구현하였다 제안된 분산 기법은 클래스의 분할 과정과 할당 과정으로 구성된다. 클래스의 분할 과정에서는 메소드, 계승 및 복합 객체와 같은 객체지항 데이터베이스의 특성을 반영하여 클래스를 분할하였으며 할당 과정에서는 저장, 질의 처리 및 전송비용을 고려하여 할당수식을 정의하였으며 이를 유전자 알고리즘을 이용하여 구현하였다.

• 한국언론정보학보
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• 제59권
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• pp.211-232
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• 2012

스마트 미디어의 폭발적인 성장으로 최근 N스크린 서비스가 각광을 받고 있다. 그러나 N스크린 서비스가 실시간 채널을 제공하면서 콘텐츠 제작사와 서비스 제공 업체 간 저작권 문제를 초래하고 있다. 본고에서는 최근 슬링박스와 같이 N스크린을 활성화시키는 수단에 의해 야기된 공중송신권과 사적복제와 관련된 방송영상저작물의 권리관계를 살펴봄으로써 향후 예견되는 N스크린 시대의 저작권 문제를 조망하고자 한다.

• 한국기록관리학회지
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• 제7권1호
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• pp.145-170
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• 2007

종이기록과 달리 특정 하드웨어와 소프트웨어의 조합에 의해서만 접근 가능한 전자기록은 그들의 생산에 이용된 저장매체, 하드웨어와 소프트웨어, 포맷의 수명보다 훨씬 더 길뿐만 아니라 시간이 흐르면 퇴화되거나 노후화되기 때문에 이에 대한 대비가 철저하게 이루어져야만 디지털정보의 장기보존과 접근, 미래 특정시점에서의 재현성을 보장할 수 있다. 이에 본 연구에서는 전자기록의 장기보존과 장기 접근성 유지에 근간이 되는 기술정보요소를 지속적으로 수집 관리하여 마이그레이션이나 에뮬레이션과 같은 보존 전략을 효율적으로 지원하는 포맷등록시스템 개발 방안을 제안하였다.

• Journal of Information Technology Applications and Management
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• 제12권2호
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• pp.129-143
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• 2005

In recent years, two major streams in medical information systems are：1) system integration among OCS(Order Communication System), EMR(Electronic Medical Record), PACS(Picture Archiving and Communication System), and ERP(Enterprise Resource Planning) and 2) system integration through medical collaboration between East and West medical service providers. One of the characteristics which differentiate the Korean medical industry from the western medical industry is the East-West medical collaboration. In many respects there are many differences between East and West medical treatment. Although East and West medical treatment have developed from different medical philosophies and standards, we assume that the better medical care can be provided by integrating their medical procedures effectively. The two possible approaches to the integration of East and West medical information systems are suggested in this paper：One is loosely coupled model and the other is tightly coupled model. EMR improves the quality of medical record which reflects the quality of clinical practice. It provides more efficient and convenient way of input, retrieval, storage, communication and management of medical data. We abstracted the standard medical procedures from the two medical procedures performed in Daejeon Oriental Hospital and Hehwa Clinic at Daejeon University and also abstracted database schema by analyzing the characteristics of information needed in East-West medical collaboration. Our EMR is composed of two types of data：one is structured data and the other is unstructured data, which are formalized by SOAP(Subjective, Objective, Assessment, Plan) format. Currently the integrated system is implemented and operated successfully for six months.

• Journal of Information Technology Applications and Management
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• 제12권3호
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• pp.27-39
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• 2005

The Semantic Web has increased the interest in ontologies recently Ontology is an essential component of the semantic web and continues to change and evolve. We consider versions management schemes in ontology. We study a set of changes based on domain changes, changes in conceptualization, metadata changes, and temporal dimension. Our change specification is represented by a set of changes. A set of changes consists of instance data change, structural change, and identifier change. In order to support a query in ontology versions, we consider temporal dimension includes valid time. Ontology versioning brings about massive amount of versions to be stored and maintained. We present the ontology versions management schemes that are 1) storing all the change sets, 2) storing the aggregation of change sets periodically, and 3) storing the aggregation of change sets using an adaptive criterion. We conduct a set of experiments to compare the performance of each versions management schemes. We present the experimental results for evaluating the performance of the three version management schemes from scheme 1 to scheme 3. Scheme 1 has the least storage usage. The average response time in Scheme 1 is extremely large, those of Scheme 3 is smaller than Scheme 2. Scheme 3 shows a good performance relatively.

• Journal of Information Technology Applications and Management
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• 제18권1호
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• pp.125-141
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• 2011

As the sales volume of online shops increases, the job burden in the back-offices of the online shops also increases. Order picking is the most labor-intensive operation among the jobs in a back-office and mid-size pure click online shops are experiencing the time delay and complexity in order picking nowadays while fulfilling their customers' orders. Those warehouses of the mid-size shops are based on manual systems, and as order pickings are repeated, the warehouses get a mess and lots of products in those warehouses are getting missing, which results in severe delay in order picking. To overcome this kind of problem in online clothing shops, we research a methodology to locate warehousing products. When products arrive at a warehouse, they are packed into a box and located on a rack in the warehouse. At this point, the operator should determine the box to be put in and the location on the rack for the box to be put on. This problem could be formulated as an Integer Programming model, but the branch-and bound algorithm to solve the IP model requires enormous computation, and sometimes it is even impossible to get a solution in a proper time. So, we relaxed the problem, developed a set of heuristics as a methodology to get a semi-optimum in an acceptable time, and proved by an experiment that the solutions by our methodology are satisfactory and acceptable by field managers.

• 전기학회논문지
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• 제64권12호
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• pp.1666-1672
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• 2015

Small islands are quite adequate places where microgrid system with renewable sources can replace diesel engines as operation costs of diesel engine in most small islands are very high. To get the large amount of renewable energy, the microgrid system has very large capacity of renewable sources. The system with large capacity of renewable sources can meet the case when supplied energy is greater than the load and the fluctuation of source output is very large. The battery energy storage system can be a solution to stabilize the system with large capacity of renewable sources. In this case, BESS can be utilized as a master source for the synchronous operation of all sources including diesel engine, wind turbine and PV. The diesel generators can be used as a backup in case the BESS SOC goes below a certain level. In this paper, we suggest a novel unit commitment of diesel generators and operation schedule of pump for water supply service with the information of wind forecast, PV forecast, and load forecast. The proposed methods has been implemented and tested at the test bed in Gasa-Island.

• Nuclear Engineering and Technology
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• 제28권3호
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• pp.257-264
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• 1996

The conventional Equipment Environment Qualification (EEQ) envelope is developed based on the containment responses during the design basis events. The Safety Depressurization System (SDS) design without In-containment Refueling Water Storage Tank (IRWST) adopted in the Ulchin 3&4 challenges the conventional EEQ envelope during long term Feed and Bleed (F&B) operation due to the direct discharge of high mass and energy into the containment. Therefore, it is necessary to confirm that the containment pressure and temperature history during the long term F&B operation does not violate the conventional EEQ envelope. However, this subject has never been quantitatively assessed before. To investigate the success path of long term F&B operation this paper analyzes the thermal hydraulic response of the containment and Reactor Coolant System (RCS) until the completion of depressurization and cooldown of RCS into Shutdown Cooling System (SCS) entry condition. It is found that the SCS entry condition can be reached within 6 hours without violating the EEQ curve by proper operation of SDS valves, High Pressure Safety Injection (HPSI) pumps and active Containment Heat Removal System (CHRS). The suggested strategy not only demonstrates the feasibility of long term F&B operation but also can be utilized in the preparation of Emergency Procedure Guidelines (EPGs)

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권12호
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• pp.5654-5668
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• 2018

Driven by security and real-time demands of Internet of Things (IoT), the timing of fog computing and edge computing have gradually come into place. Gateways bear more nearby computing, storage, analysis and as an intelligent broker of the whole computing lifecycle in between local devices and the remote cloud. In fog computing, the edge broker requires X-aware capabilities that combines software programmability, stream processing, hardware optimization and various connectivity to deal with such as security, data abstraction, network latency, service classification and workload allocation strategy. The prosperous of Field Programmable Gate Array (FPGA) pushes the possibility of gateway capabilities further landed. In this paper, we propose a software-defined gateway (SDG) scheme for fog computing paradigm termed as Fog Computing Zero-Knowledge Gateway that strengthens data protection and resilience merits designed for industrial internet of things or highly privacy concerned hybrid cloud scenarios. It is a proxy for fog nodes and able to integrate with existing commodity gateways. The contribution is that it converts Privacy-Enhancing Technologies rules into provable statements without knowing original sensitive data and guarantees privacy rules applied to the sensitive data before being propagated while preventing potential leakage threats. Some logical functions can be offloaded to any programmable micro-controller embedded to achieve higher computing efficiency.

• 한국표면공학회지
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• 제54권4호
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• pp.164-170
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• 2021

Vanadium redox flow batteries (VRFB) have emerged as large-scale energy storage systems (ESS) due to their advantages such as low cross-contamination, long life, and flexible design. However, Hydrogen evolution reaction (HER) in the negative half-cell causes a harmful influence on the performance of the VRFB by consuming current. Moreover, HER hinders V²⁺/V³⁺ redox reaction between electrode and electrolyte by forming a bubble. To address the HER problem, carbon nanotube/graphite felt electrode (CNT/GF) with oxygen functional groups was synthesized through the hydrothermal method in the H₂SO₄ + HNO₃ (3:1) mixed acid solution. These oxygen functional groups on the CNT/GF succeed in suppressing the HER and improving charge transfer for V²⁺/V³⁺ redox reaction. As a result, the oxygen functional group applied electrode exhibited a low overpotential of 0.395 V for V²⁺/V³⁺ redox reaction. Hence, this work could offer a new strategy to design and synthesize effective electrodes for HER suppression and improving the energy density of VRFB.