• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.334-336
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• 2006

본 논문에서는 계층적인 센서 네트워크에서 하위 센서 노드의 인증이나 센싱된 정보의 암호화를 위해 사용할 수 있는 키를 관리하기 위하여 키 선분배를 기본으로 키 재분배 방법을 제공하는 키 관리 메커니즘을 제안한다. 본 키 관리의 특징은 첫째, 중앙 관리의 약점을 극복하기 위해 키 관리를 다른 aggregator 노드들에 분산시켰다. 둘째, SINK 노드는 키의 재분배를 위한 키 스페이스를 제외하고, 이미 분배된 키에 대해서는 어느 노드에게 어떤 키를 분배했는지 또는 그 키 자체를 저장하지 않고, 키 계산을 위한 일부 정보만 저장하고 있다가 노드가 메시지에 첨부하여 주는 키 정보를 이용해 사용된 키를 간단히 계산하며, 키 풀의 확장이 용이하여 확장성을 제공한다. 마지막으로 계산 및 메모리 측면에서의 오버헤드 분석을 통해 제안된 키 관리의 확장성 제공을 입증한다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1705-1711
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• 2017

This paper analyzes the impact of DRA (Demand Response Aggregator) on market power when competing with power generation companies (Gencos) in the electricity market. If congestion occurs in the transmission line, the strategic choice of the power generation company increases exercise of market power. DRA's strategic reduction of power load impacts the strategy of Gencos, which in turn affects the outcome of the load reduction. As the strategy of Gencos changes according to the location of the congested transmission line, the impact on the market depends on the relative location of the congested line and the DRA.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.292-295
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• 2008

We propose a PON repeater system which transports multiple PON channels at the same time over the physical limit of the standard E-PON reach. To increase the physical reach up to 60km, we used the O-E-O (optic-electric-optic) signal regeneration on an active remote terminal which is placed between a central office and passive remote nodes. Also, by incorporating the well-established WDM technology to aggregate multiple E-PON channels, we successfully increased the split ratio (the number of subscribers per fiber core) to over 256.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.7 s.349
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• pp.1-13
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• 2006

In this paper, we introduce a novel key management scheme that is based on the key pre-distribution but provides the key re-distribution method, in order to manage keys for message encryption and authentication of lower-layer sensor nodes on hierarchical mobile sensor networks. The characteristics of our key management are as follows: First, the role of key management is distributed to aggregator nodes as well as a sink node, to overcome the weakness of centralized management. Second, a sink node generates keys using regression model, thus it stores only the information for calculating the keys using the key information received from nodes, but does not store the relationship between a node and a key, and the keys themselves. As the disadvantage of existing key pre-distributions, they do not support the key re-distribution after the deployment of nodes, and it is hard to extend the key information in the case that sensor nodes in the network enlarge. Thirdly, our mechanism provides the resilience to node capture(${\lambda}$-security), also provided by the existing key pre-distributions, and fourth offers the key freshness through key re-distribution, key distribution to mobile nodes, and scalability to make up for the weak points in the existing key pre-distributions. Fifth, our mechanism does not fix the relationship between a node and a key, thus supports the anonymity and untraceability of mobile nodes. Lastly, we compare ours with existing mechanisms, and verify our performance through the overhead analysis of communication, computation, and memory.

• Journal of Energy Engineering
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• v.16 no.4
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• pp.202-214
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• 2007

The concept of HSA (Home Service Aggregator) is derived from performing the energy IT business efficiently as well as successfully launcing a new service based on BPL (Broadband over Power Line). The HSA business using a BPL can extend the field of energy industry and an give a chance to create a new demand by consumer-oriented services. This study focuses on the exact evaluation of HSA business using BPL, and reasonable trusty evaluation should be the first step to launch the HSA business. In this study, the categories of cost are comprised of equipment (mainly RSM and MGW) cost, instalation cost, and maintenance cost. AMR (Automatic Meter Reading), internet integration billing service, integration charging service, internet service, sorority service, and electricity safety are listed for benefit. In this study, the ROI of HSA business is 0.9594, which is less than 1. However, that value does not consider the electricity safety benefit which is classified as a social benefit. Therefore, the value can be above 1 if it includes social and private benefits.

• Structural Engineering and Mechanics
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• v.75 no.3
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• pp.389-399
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• 2020

An infill wall made of high-performance fiber-reinforced cementitious composites (HPFRCC) was utilized in this study to strengthen the reinforced concrete (RC) frame structures that had not been designed for seismic loads. The seismic performance of the RC frame structures strengthened by the HPFRCC infill walls was investigated through the experimental tests, and the test results showed that they have improved strength and deformation capabilities compared to that strengthened by the RC infill wall. A simple numerical modeling method, called the modified longitudinal and diagonal line element model (LDLEM), was introduced to consider the seismic strengthening effect of the infill walls, in which a section aggregator approach was also utilized to reflect the effect of shear in the column members of the RC frames. The proposed model showed accurate estimations on the strength, stiffness, and failure modes of the test specimens strengthened by the infill walls with and without fibers.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.12a
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• pp.177-190
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• 1999

개방과 경쟁의 도입, 기술의 발달, 고객욕구의 다양화 및 고급화 등과 같은 제반 환경요인의 변화로 최근의 정보통신산업에서는 많은 변화가 야기되고 있다. 특히 별정통신이라는 이름으로 도입된 새로운 사업형태는 탄생상의 문제, 경험과 지식의 부족 및 상층되는 목표로 인하여 정착되어 가는 과정에서 문제와 불협화음이 발생하고 있다. 이러한 문제는 제도, 기능, 시장 그리고 사업자 관계라는 네가지 측면으로 집약될 수 있다. 이에 본 연구는 별정 2호 사업을 숭심으로 유통기능에 대한 검토 및 분석을 통해 유통구조 시스템의 전략적 설계 방향을 다음과 같이 제시하였다. 첫째, 기간통신사업자의 사내 유통망을 보완해주는 사외유통망을 설계함으로써 유통효율성과 마케팅 효과성을 동시에 제고해야 한다는 것이다. 둘째, 별정통신 유통경로 시스템을 발전적 마케팅 전략의 일환으로 통신서비스 제공이라는 단순한 차원을 뛰어넘어 고객생활의 질을 향상시키고 고객의 성공을 가져오는 폭넓고 고차원적인 개념으로 확대하여야 할 것이다. 이러한 기반 위에 통신사업에 대한 홍보활동을 강화하고 다양한 통신서비스를 제공할 수 있는 서비스 충실화를 기하여야 할 것이다. 셋째, 기간통신사업자가 강점을 갖고 있는 영역에 대해서는 기존의 직접마케팅을 활용하고, 약점을 가지고 있는 서비스나 기능에 대해서는 대체하거나 보완하는 역할을 별정사업자에게 부과함으로써 전체 서비스 제공 시스템의 목적을 달성할 수 있을 것이다.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.2
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• pp.145-157
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• 2015

Objective : This study aimed to analyze a comprehensive feature of experimental research on Insamyangyoungtang and develop a strategy that can be used for experimental studies on Insamyangyoung-tang in the future. Method : The journal search was performed using six databases : PubMed, Chinese database (China Network Knowledge Infrastructure, [CNKI]), Japan database (Japan Science and Technology Information Aggregator, Electronic, [J-STAGE]) and three Korean databases (Oriental Medicine Advanced Searching Integrated System [OASIS], Research Information Service System [RISS], and Korean Studies Information Service System [KISS]). We used limited keywords and analyzed studies by publication year, experimental models, and the subjects of biological activities. The mechanism of pharmacological activity in accordance with the therapeutic effects of Insamyangyoung-tang was noted. Results and Conclusion : A total of 43 studies (6 domestic studies and 37 foreign ones) were examined according to the inclusion criteria of the experimental study. Research on the pharmacological activities of Insamyangyoung-tang showed its therapeutic effects on the nervous and immune systems, as well as its anti-aging, anti-fatigue, and hematopoietic effects. Additional efficacy and safety assessments and experimental and clinical studies should be performed to evaluate the mechanism of Insamyangyoung-tang. The present review has provided preliminary information for further studies on Insamyangyoung-tang.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.720-725
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• 2009

SDI(Selective Dissemination of Information) is on demand service to inform to the user applies a service after inputting a search strategy, when new information is obtained. This Paper propose the ways to develope the dynamic RSS channel generator for supporting SDI service. The RSS which is a kind of syndication technology enables a part or the whole of the content which it provides from web site to be able to be used in different service. It is protocol to summarize and share various contents on web site. Also, the users register the channel RSS to the RSS aggregator system and recommend it. It can drive to share of knowledge between researchers.

• IEMEK Journal of Embedded Systems and Applications
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• v.7 no.1
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• pp.9-15
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• 2012

Recently, as the development of 3D contents service, production of 4D media that user can feel physical effects by the scene of movie has been increased. This 4D media uses the SMMD (Single Media Multiple Devices) method to give users enhanced effects with multiple devices playing rather than the SMSD (Single Media Single Device) method with single device playing in a smart TV environment. To give more sensible effects to users, from the beginning of making one media, we produced 4D media that consists of 3D contents and the SEM (Sensory Effect Metadata) to define effects of the scene. 4D media is transmitted to a HS (Home Server) to represent 3D contents in 3DTV and multiple devices with synchronized way. In this paper, we suggested the concept and overall 4D media broadcasting service system architecture, aggregator time acquisition, media time scheduling, real-sense device scheduling, evaluation results, user interfaces and implemented devices.