• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.744-749
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• 2013

The protection switching technology is widely adopted in the fiber-optical transmission equipments based on TDM(Time Division Multiplexing), such as PDH, SDH/SONET. A variety of protection switching algorithms for Ethernet networks and the progress of standardization are summarized in the document. There are several kinds of protection switching algorithms for Ethernet networks, such as STP, RSTP, MSTP and etc. However, since Ethernet signal move through detour route, it causes much time to recover. Accordingly, it is difficult to secure a usability of Ethernet networks and QOS(Quality of Service). Also, if the protection switching protocol standardized by IEEE and ITU-T is used, it remains a inherent network switching time for protection. Therefore, a specific protection switching algorithm for Ethernet are needed for seamless and stable operation of Ethernet networks service for Distribution Automation System(DAS). A reliable protection algorithm with no switching delay time is very important to implement Self-healing service for DAS. This study of FPGA based protection switching algorithm for Ethernet networks shows that in case of faults occurrence on distribution power network, immediate fault isolation and restoration are conducted through interaction with distribution equipments using P2P(Peer to Peer) communication for protection coordination. It is concluded that FPGA based protection switching algorithm for Ethernet networks available 0ms switching time is crucial technology to secure reliability of DAS.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.30 no.2
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• pp.102-111
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• 2021

Implant placement in the anterior region is performed in several stages, and harmonization of both hard and soft tissues is essential. In addition, adequate esthetic and functional evaluations are necessary in the process of transitioning from the provisional to the final prosthesis to attain patient satisfaction. Although gingiva can be molded in the anterior region, depression in the occlusal view can yield good results through the augmentation procedure. However, the harvesting of connective tissue from the palate is not suitable for various reasons, such as postoperative discomfort and intraoperative bleeding. Compared to the palatal area, the harvesting of connective tissue from the maxillary tuberosity can easily result in relatively thick tissue and quick healing of the donor site, thus proving to be a good modality for graft procedures. The purpose of this report is to examine the relevant evidence from previous studies and evaluate the process of soft tissue augmentation through a case presentation.

• The Korean Journal of Health Service Management
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• v.11 no.4
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• pp.157-168
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• 2017

Objectives : The purpose of the study was to provide basic data for the improvement of their happiness through the use of effective denture-related services and restoration of healthy oral function. Methods : The subjects of the study were 452 denture wearers using the elderly welfare facilities in Seoul. Results : The main variables influencing the happiness of the denture wearers were living with the family, subjective health, oral health status, duration of denture use, and regular oral examinations. Living with one's family had the greatest influence on the happiness of the denture wearers. Conclusions : This study discusses the effect of satisfaction and behavior factors on effective denture use with reference to the happiness of denture wearers. This information will help improve denture management programs.

• Korean Journal of Veterinary Service
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• v.30 no.3
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• pp.459-466
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• 2007

The Korean Musk deer (Moschus Moschiferus) is endangered due to heavy hunting and Massive destructions of natural habitat. They are included in CITES appendix II. In addition they are designated as a precious natural product in 1968 and listed as endangered species by the Government and Cultural Heritage Administration. At present, the number of musk deer in Korea is smaller than minimum viable population. Without increment of the population size, natural restoration is impossible. It is necessary to develop the artificial growth and re-enforcement methods in order to conservation Korean musk deer. Furthermore, It is necessary to ensure that we have an adequate individual group for artificial growth and re-enforcement. To ensure that we have an adequate individual group, it is necessary to know ecology of musk deer. This study is conducted to confirm and investigate of habitat of musk deer in order to capture individual musk deer. we investigated, confirmed habitats, found traces and captured using trap and decoy. Captured musk deer is male and 5.5 kg, this have canine tooth of 1.5cm, is estimated 15 months old. After capture, we measured each parts of body and tested to research of parasite infection. Strongyloides papillous was founded in the feces. It is essential to get healthy individual and establish of artificial growth technique.

• Journal of the military operations research society of Korea
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• v.28 no.1
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• pp.115-135
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• 2002

The limits of current DN(Defense networks), private and closed network, become to reality; for Example, high expense of construction and maintenance of networks, restriction of new subscribers on DN. Therefore, a network using web environment that reflect fast development of If and IS(Information Security) technology is demanded for MND. Meeting the requirement of reliable IS system and extension and improvement of DN using common network, we can reduce the expense to extend, maintain, repair DN, form the environment that makes military business cooperate better with civil company and government agency, advance implementing Defense computing and networking service for field small size units that was a exception of Defense digitalization. But it is essential to construct DN based on common network that there are security requisites; confidentiality, integrity, availability, efficiency, log, backup, restoration, that have to be realized at demanding level for IS. This thesis suggested four measurements; replacement DN with common network to resolve the requirements of building new network and improvement of performance for private DN, linkage with common network for new requirement, distribution of traffic using common network, configuration of DN using Internet and Proposed a refinement of IS management organization to treat security threat of common network flexibly, and LAN IS standard model of DN based on the web environment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.2
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• pp.43-48
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• 2016

Operational applications such as service restoration, voltage control and protection coordination are calculated based on the active and reactive power loading of the sections in the distribution networks. Loadings of the sections are estimated using the voltage and current measured from the automatic switches deployed along the primary feeders. But, due to the characteristics of the potential transformer attached to the switches, accuracy of the voltage magnitude is not acceptable to be used for section loading calculation. This paper proposes a new accurate section loading estimation method through voltage measurement error compensation by calculating voltage drop of the distribution line. In order to establish feasibility of the proposed method, various case studies based on Matlab simulation have been performed.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.486-493
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• 2010

This paper demonstrates the design and implementation of fruit larder system that is able to monitor and control restoration environment using mobile equipment. Based on RFID/USN technology, it builds wireless sensor network to enhance its efficiency to fruit larder environment and inventory management and performs automated environment management through window-based application that works in desktop environment. Additionally, using WINC service, it provides remote control function for fruit larder using mobile equipment.

• Journal of Electrical Engineering and Technology
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• v.3 no.3
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• pp.331-336
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• 2008

Electric load components have different characteristics according to the variation of voltage and frequency. This paper presents the load modeling of an electric locomotive by the parameter identification method. The proposed method for load modeling is very simple and easy for application. The proposed load model of the electric locomotive is represented by the combination of the loads that have static and dynamic characteristics. This load modeling is applied to the KTX in Korea to verify the effectiveness of the proposed method. The results of proposed load modeling by the parameter identification follow the field measurements very exactly.

• KIEE International Transactions on Power Engineering
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• v.4A no.1
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• pp.42-47
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• 2004

This paper presents the various application programs for the Distribution Automation System (DAS) of the Korea Electric Power Corporation (KEPCO)'s distribution system. These programs are developed to allow for optimal operation in the areas of feeder automation, relay coordination, loss minimization and so on. They are single line diagram auto creation programs for the feeder, service restoration program, protection coordination program, data error detection program, and optimal network reconfiguration program. The details of these programs are presented for validity and effectiveness.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.382-384
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• 2000

산업의 발달에 따라 배전계통의 자동화가 서서히 자리 매김하고 있다. 이에 따라 배전계통에서 발생하는 사고를 계통의 상태와 신뢰도를 동시에 만족시키고, 빠른 시간 내에 복구하는 문제는 매우 중요한 문제로 대두되고 있다. 배전계통 사고복구 문제는 많은 개폐기들의 조합에 의해 구성되어 있고, 계통의 구성상태 와 연계선로의 예비력 등 많은 제약조건들로 인하여 사고복구에 많은 시간이 걸린다. 본 논문에서는 유전 알고리즘과 Tabu Search (TS) 기법을 이용하여 계통의 사고 후 선로손실과 신뢰도손실을 최소로하는 배전계통 사고복구 알고리즘을 제안하고자 한다. 전역 최적해 탐색 및 여러 해의 동시 탐색이 가능한 유전알고리즘과 전역적 탐색은 약하지만 빠른 시간 내의 국부적 탐색(local search)이 우수한 TS를 서로 연계한 알고리즘의 우수성을 계통의 모의실험을 통하여 증명하였다.