• The KIPS Transactions:PartC
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• v.18C no.5
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• pp.339-342
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• 2011

This paper proposes a network-based mobility control scheme in wireless/mobile networks, which is based on the Locator-Identifier Separation Protocol (LISP). Compared to the existing LISP mobility scheme, the proposed scheme is featured by the following two points: 1) each LISP Tunnel Router (TR) is implemented at the first-hop access router that mobile nodes are attached to, and 2) for handover support, the LISP Routing Locator (RLOC) update operation is performed between Ingress TR and Egress TR. By numerical analysis, it is shown that the proposed scheme can reduce the handover latency much more than the other candidate schemes.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.1
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• pp.47-52
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• 2016

Fault location identification in the transmission line is an essential part of quick service restoration for maintaining a stable in power system. The application of digital schemes to protection IEDs has led to the development of digital fault locators. Normally, the impedance measurement had been used to for the location detection of transmission line faults. It is well known that the most accurate fault location scheme uses two-ended measurements. This paper deals with the complete design of a fault locator using GPS time-synchronized phasor for transmission line fault detection. The fault location algorithm uses the transmitted relaying signals from the two-ended terminal. The fault locator hardware consists of a Main Processor Unit, Analog Digital Processor Unit, Signal Interface Unit, and Power module. In this paper, sample real-time test cases using COMTRADE format of Omicron apparatus are included. We can see that the implemented fault locator identified all the test faults.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.2
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• pp.209-217
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• 2014

Of several approaches for future Internet, separating two properties of IP address into locator and identifier, is being considered as a highly likely solution. IETF's LISP (Locator ID Separation Protocol) is proposed for this architecture. In particular, the LISP model easily allows for device mobility through simple update of information at MS (Mapping Server) without a separate protocol. In recent years, some of the models supporting device mobility using such LISP attributes have emerged; however, most of them have the limitation for seamless mobility support due to the frequent MS information updates and the time required for the updates. In this paper, PMIPv6 (Proxy Mobile IPv6) model is applied for mobility support in LISP model. PMIPv6 is a method that can support mobility based on network without the help of device; thus, this we define anew the behavior of functional modules (LMA, MAG and MS) to fit this model to the LISP environment and present specifically procedures of device registration, data transfer, route optimization and handover. In addition, our approach improves the communication performance using three tunnels identified with locators between mobile node and corresponding node and using a route optimized tunnel between MN's MAG and CN's MAG. Finally, it allows for seamless mobility by designing a sophisticated handover procedure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.3
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• pp.504-510
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• 2016

In general, a fault locator is installed in Sub-Station of AT(Auto-transformer) feeding system to estimate the fault location and to protect the Korean AT feeding system. Since the line impedance characteristic is different to normal 3-phase transmission line, we need particular modification factors, which can be calculated using fault location recording data, to estimate the accurate fault location. Up to recently, forcible ground test has been used to calculate the modification factors of the fault locator. However, large amount of current is occurred when the forcible ground test is performed, and this current affects to adjacent equipments. Therefore, we proposed a novel calculation method of modification factors, arbitrary trip test, using boosting current of the operating electric train. Through several field test, we confirmed that modification factors for fault locator can be easily calculated by using proposed method. Moreover, we verified the accuracy and stability of the proposed calculation method.

• The Journal of Advanced Prosthodontics
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• v.4 no.2
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• pp.116-120
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• 2012

Various options have been introduced for the selection of implant overdenture attachments. Attachment wear due to the repeated insertion and removal of dentures has caused problems such as decreased retention and the requirement for suprastructure remanufacturing. In these cases, a Locator bar system was applied using the drill and tapping technique to achieve total retrievability. In a 55-year-old female patient who showed three degrees of mobility in most of her teeth due to severe alveolar bone loss, a complete denture in the maxilla and an implant supported type overdenture in the mandible were planned after extracting all the remaining teeth. Six implants were placed from canine region to the distal molar region, and the locator was connected to the milled bar using the drill and tapping technique. For a 61-year-old female edentulous patient who complained of poor retention with old denture, a complete denture in the maxilla and an implant-tissue supported type overdenture in the mandible were planned. Four implants were placed in front of mental foramen, and the Locator was also connected to the Hader bar using the drill and tapping technique. With this technique, female parts can be easily replaced, and retention can be continuously maintained.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.368-374
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• 2018

In this case, the patient was restored with gold Hader bar mandibular implant overdenture using two implants about 10 years ago, and the retentive force was lost due to severe wear of the bar due to 3.5 years use. The overdenture was repaired using a Locator attachment, but the male part was completely worn after 6.5 years use. Finally, we used a hybrid telescopic double crown with a friction pin to fabricate a new implant overdenture, which was observed for 2 years and showed excellent prognosis. So, we describe the cause of failure of each attachment (Gold Hader bar, Locator) in two implant overdentures and report on the advantages and disadvantages of double crown implant overdenture and the conditions for success.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.1
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• pp.55-62
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• 2017

Overdenture using dental implants could improve the problems of conventional complete denture function which are pain during mastication, insufficient retention and stability. Locator attachment used widely for implant-retained overdenture has advantages that it needs the smallest vertical space and also its nylon male cap allows personalized retention for each case. However its retention force decreases rapidly with function rather than the bar and ball attachment. So, implant fixture should be positioned as parallel as possible.

• Restorative Dentistry and Endodontics
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• v.41 no.1
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• pp.6-11
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• 2016

Objectives: The purpose of this in vitro study was to evaluate the accuracy of working length (WL) determination of four electronic apex locators (EALs), namely, Root ZX (RZX), Elements diagnostic unit and apex locator (ELE), SybronEndo Mini Apex locator (MINI) and Propex pixi (PIXI) using Stainless steel (SS) and nickel-titanium (NiTi) hand files. The null hypothesis was that there was no difference between canal length determination by SS and NiTi files of 4 EALs. Materials and Methods: Sixty extracted, single rooted human teeth were decoronated and the canal orifice flared. The actual length (AL) was assessed visually, and the teeth were embedded in an alginate model. The electronic length (EL) measurements were recorded with all four EALs using SS and NiTi files at '0.5' reading on display. The differences between the AL and EL were compared. Results: The results obtained with each EAL with SS and NiTi files were compared with AL. A paired sample t test showed that there was a statistical significant difference between EAL readings with SS and NiTi files for RZX and MINI (p < 0.05). The accuracy of RZX, ELE, MINI and PIXI within ${\pm}0.5 mm$ of AL with SS/NiTi files were 93.3%/70%, 90%/91.7%, 95%/68.3%, and 83.3%/83.3%, respectively. Conclusions: The results of this study indicate that Root ZX was statistically more accurate with NiTi files compared to SS files, while MINI was statistically more accurate with SS files compared to NiTi files. ELE and PIXI were not affected by the alloy type of the file used to determine WL.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.338-340
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• 2016

최근 사물인터넷에 대한 관심이 증가함에 따라 미래인터넷에 대한 연구가 증가하고 있다. 각기 다른 사물인터넷을 연결하기 위하여 다양한 네트워크 인프라가 필요하며, 사용자뿐만 아니라 다양한 네트워크 자원에서 요구하는 서비스나 콘텐츠 등이 증가하고 있다. 이에 따라 이들을 식별하기 위한 통일된 식별 체계가 필요하다. 이를 위하여 미국에서는 NDN에 대한 연구가 진행 중이며, 이외에도 MobilityFirst, XIA와 같은 프로젝트성 연구들이 활발히 이루어지고 있다. 따라서, 본 논문에서는 기존의 연구들을 보완하고 새로운 미래인터넷에 확장 가능한 통합된 Name-Identifier-Locator 프레임워크를 제안한다.

• Electronics and Telecommunications Trends
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• v.28 no.3
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• pp.95-105
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• 2013

현재의 인터넷은 라우팅과 어드레싱에 대한 심각한 확장성 문제를 가지고 있다. 이러한 확장성의 가장 큰 원인은 멀티호밍, 트래픽 엔지니어링, 집적되지 못하는 주소 할당 등이며, 이로 인하여 백본 지역의 라우팅 테이블 크기가 기하급수적으로 증가하는 현상을 보이고 있다. 또한 현재의 IP 주소는 호스트의 식별자와 위치자의 의미를 함께 사용하기 때문에 호스트의 이동성 및 멀티호밍을 지원하는 데 한계점이 있다. 이러한 현재 인터넷의 문제점 해결 방안으로 식별자와 위치자 분리 구조가 연구되고 있다. 본고에서는 식별자와 위치자 분리 구조에서 필수적으로 요구되는 식별자와 위치자 간의 매핑 시스템에 관한 연구들을 소개하고 각각의 장단점을 분석한다. 본고에서는 현재 인터넷 기반의 대표적 식별자와 위치자 분리 구조 중 IETF(Internet Engineering Task Force)에서 잘 알려진 LISP(Locator Identifier Separation Protocol), HIP(Host Identity Protocol), ILNP(Identifier Locator Network Protocol)에서 제안하는 매핑 시스템들과 미래인터넷 기반의 대표적 식별자와 위치자 분리 구조 중 미국의 MobilityFirst와 한국의 MOFI(Mobile-Oriented Future Internet)에서 제안하는 매핑 시스템들을 중점적으로 소개한다.