• 한국통신학회논문지
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• 제18권8호
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• pp.1108-1116
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• 1993

두개의 다른 결합길이를 갖는 Y분기 방향성 결합기 광스위치를 z-cut LiNbO3로 제작하였고, r = 1.3rm에서 체스트하였다. 소자와 결합길이를 계산하기 위하여 정상모드 이론과 결합모드 이론을 사용하였다. 망전송 이론의 전산모의를 통하여 소자의 결합길이를 재 확인하였다. 직류동작시 실험 결과치들이 결합모드 이론에 의한 예측치와 잘 부합 하였다.

• Progress in Superconductivity
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• 제6권1호
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• pp.52-55
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• 2004

The inductive coupling theory in serially stacked $Bi_2$$Sr_2$$CaCu_2$$O_{8+x}$ intrinsic Josephson junctions predicts that the lattice structure of the Josephson vortices along the c axis gradually changes from the triangular to the rectangular lattice with increasing the vortex velocity. This lattice transition appears as voltage jumps or sub-branch splitting in the Josephson vortex-flow region of current-voltage characteristics (IVC). We report the IVC in external magnetic fields from 2 to 4 T. The stack, with the lateral size of 1.4${\times}$15 $u\m^2$, was fabricated by using the double-side cleaving technique. The sub-branches in the Josephson vortex-flow region, corresponding to a plasma propagation mode in serially coupled intrinsic Josephson junctions, were also observed in the range of 2∼4T. Switching from one branch to another in Josephson vortex-flow region suggests the structural transition of the moving Josephson vortex lattice.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2008년도 동계학술대회
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• pp.25-28
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• 2008

Shirai 등은 FSE'04에서 DSM 설계 원리를 적용하여 증명 가능한 Feistal 구조를 제안하였다. 제안된 구조는 임의의 라운드 수에 대하여 능동 S-box의 최소 개수를 증명할 수 있다. 그러나 제안된 구조에 제약된 조건을 만족하는 행렬이 존재함을 증명하지 못하였다. 본 논문에서는 DSM 설계 원리에 최대 branch number를 갖는 $m{\times}m$ 이진 행렬을 적용하였을 경우 동일한 최대 branch number를 가지지 못함을 증명 한다$(m{\leq}34)$. 이는 이진 행렬을 이용하여 Shirai 등이 제안한 구조를 설계할 수 없음을 의미한다.

• 전기의세계
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• 제17권4호
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• pp.18-27
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• 1968

Analysis of the transient stability of power systems following disturbances involves many sets of non-linear differential equations. This paper attempts to analyze the transient stability of multi-machine power systems by the step by step method, using the electronic digital computer. The critical switching times and phase angles for the main 154KV transmission system in Korea, are given from the swing curves of the probable conditions. It is concluded that the system is, in general, stable if the relay is cut off within 12 cycles after the fault. However the fault of DAEGU-SANGJU branch, accompanying much real power, makes the system unstable when the raly is cut off within 4 cycles after fault or automatic voltage regulators are equipped in this branch.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.258_259
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• 2009

This paper describes the development of robust processor for analyzing network state in Korean Energy Management System. The important function of topology processing is to convert the switching/device model into a bus/branch model by the status of switching devices. The state estimator also provides a consistent unified solution, not only for measurement of the observable system, but also for the unobservable system. The primary function of the online power flow is to provide a highly reliable and flexible power flow solution that can be used to solve a wide variety of power systems problems. The validity of the newly developed functions has been verified through comparative simulations with the existing EMS functions, which are currently in use in the Korean power system.

• Journal of Power Electronics
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• 제13권6호
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• pp.1058-1069
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• 2013

This paper proposes and designs a new output filter called an LCFL filter for application to three phase three wire shunt active power filters (SAPF). This LCFL filter is derived from a traditional LCL filter by replacing its capacitor with a C-type filter, and then constructing an L-C-type Filter-L (LCFL) topology. The LCFL filter can provide better switching ripple attenuation capability than traditional passive damped LCL filters. The LC branch series resonant frequency of the LCFL filter is set at the switching frequency, which can bypass most of the switching harmonic current generated by a SAPF converter. As a result, the power losses in the damping resistor of the LCFL filter can be reduced when compared to traditional passive damped LCL filters. The principle and parameter design of the LCFL filter are presented in this paper, as well as a comparison to traditional passive damped LCL filters. Simulation and experimental results are presented to validate the theoretical analyses and effectiveness of the LCFL filter.

• 한국통신학회논문지
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• 제28권8A호
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• pp.581-590
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• 2003

본 논문은 ATM 시스템에서 동적 소스 기반의 점대다중점 호를 위한 라우팅 경로 택 방법을 제안한다. 특히 최적의 경로 선택보다는 리소스를 최대한 공유할 수 있고, 경로 계산 시간 단축 및 cycle 방지를 쉽게 보장할 수 있는 점대다중점 라우팅 경로 선택 방법을 제안하였다. 리소스를 최대한 공유할 수 있도록 하기 위해 착신지(destination) 노드로부터 가장 근거리의 branch point를 찾는 것이 이 알고리즘의 목표이다. 그러므로 목적(destination) 노드로부터 역 추적에 의해 인접한 노드중 같은 Call ID를 갖는 기존 경로상의 노드와 최초로 크로스(cross)되는 노드를 branch노드로 정하여 최적의 점대다중점 라우팅 경로를 구성하는 알고리즘이다. 크로스 노드를 찾을 때까지 역추적에 의해 선택되는 최적의 노트는 다익스트라 알고리즘을 이용하여 선택된다. 즉 점대다중점 라우팅 경로 선택은 역추적에 의한 인접 노드중 기존 경로와 크로스되는 노드 선택 단계와 각 인접 노드중 최적의 노드를 선택하는 단계를 수행한다. 이 기법은 경로 선정을 위한 라우팅 정보 테이블의 검색 및 경로 계산 과정을 단축시키고, 경로 설정시 cycle방지도 쉽게 해결한다.

• 한국통신학회논문지
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• 제29권9A호
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• pp.1091-1100
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• 2004

본 논문은 최적 모듈 선택 아키텍쳐 합성을 위한 천력 감소 Force-directed 스케줄링을 제안한다. 제안한 전력 강소 스케줄링은 행위 수준 언어를 업력으로 스위칭 활동-(switching activity) 을 고려하여 기존의 FDS 스케쥴링을 저 전력으로 고려한 FDS_LP 앙고리듬을 수행한다. 제안한 FDSL LP 알고리듬은 스위칭 활동을 최소로 하는 동적 파워를 포스 개념에 적용하여 전력 감소를 수행한다. 모듈 선택에서는 전력, 면적, 지연의 매개 변수를 고려하여 최척 모율 성택 RT 라이브러리를 구축한다. 구축한 RT 라이브러리에서 최적 파라메터를 구하기 위해서 프렌치 앤드 바운드 방법을 사용한 최걱 요율 선택 방법을 제안한다. 비교 실험에서는 최적 모율 선택을 고려한 제안한 FDS LP 앙고리듬과 기존의 FDS 알고리듬간의 전력 차이를 비교하여 최대 23.9 % 까지 전력 감소를 얻을 수 있다.

• Molecules and Cells
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• 제26권1호
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• pp.5-11
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• 2008

Stalled DNA replication forks activate specific DNA repair mechanism called post-replication repair (PRR) pathways that simply bypass DNA damage. The bypassing of DNA damage by PRR prevents prolonged stalling of DNA replication that could result in double strand breaks (DSBs). Proliferating cell nuclear antigen (PCNA) functions to initiate and choose different bypassing pathways of PRR. In yeast, DNA replication forks stalled by DNA damage induces monoubiquitination of PCNA at K164, which is catalyzed by Rad6/Rad18 complex. PCNA monoubiquitination triggers the replacement of replicative polymerase with special translesion synthesis (TLS) polymerases that are able to replicate past DNA lesions. The PCNA interaction motif and/or the ubiquitin binding motif in most TLS polymerases seem to be important for the regulation of TLS. The TLS pathway is usually error-prone because TLS polymerases have low fidelity and no proofreading activity. PCNA can also be further polyubiquitinated by Ubc13/ Mms2/Rad5 complex, which adds an ubiquitin chain onto monoubiquitinated K164 of PCNA. PCNA polyubiquitination directs a different PRR pathway known as error-free damage avoidance, which uses the newly synthesized sister chromatid as a template to bypass DNA damage presumably through template switching mechanism. Mammalian homologues of all of the yeast PRR proteins have been identified, thus PRR is well conserved throughout evolution. Mutations of some PRR genes are associated with a higher risk for cancers in mice and human patients, strongly supporting the importance of PRR as a tumor suppressor pathway.

• 한국프랜차이즈경영연구
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• 제7권1호
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• pp.31-44
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• 2016

Purpose - This study aims to examine different impacts of franchisor's leadership and franchisee's marketing efforts on franchisee dissatisfaction and switching intentions, and to investigate how franchisee dissatisfaction plays a mediating role in the relationship between these constructs. This study attempted to fill the gap in the literature by treating the franchisee dissatisfaction as a mediator in the relationship between these constructs, identify how franchisor's leadership and franchisee's marketing efforts have effects on franchisee dissatisfaction, in turn, reduce switching intentions, and provide the managerial implications for building a long-term relationship to achieve mutual goals between franchisors and franchisees Research design, data, and methodology - In order to test the hypotheses, the data were collected from franchisees in Seoul and Gyeonggi Province. The franchisee owners were informed about the purpose of this study by the trained interviewers. The respondents received a letter introducing the purpose of this study and another letter that the owners wrote to encourage their active participation. Among the 300 questionnaires distributed, 260 (86.7%) questionnaires were returned. Of those collected questionnaires, 6 uncompleted responses were excluded, and 254 questionnaires with an effective response rate of 84.7% were coded and analyzed using frequency, confirmatory factor analysis, and correlations analysis, and structural equation modeling with SPSS 21.0 and SmartPLS 3.0. Results - The findings of the study are as follows. First, franchisor leadership had a negative effect on franchisee dissatisfaction, but franchisee marketing efforts did not have a significant effect on franchisee dissatisfaction. Second, franchisee dissatisfaction had a positive effect on switching intentions. Third, franchisor leadership had a negative effect on switching intentions, but franchisee marketing efforts did not have a significant effect on switching intentions. Conclusions - This study researched the franchisor's leadership as a single factor of transformational leadership. Thus, it may have limits in measuring leadership. Future studies shall include emotional, loyal, and transactional leadership. In addition, the future studies shall also research the effect of franchisor's leadership and franchisees' marketing efforts on dissatisfaction and switching intentions. For example, the franchisor's relationship-oriented efforts can be a crucial parameter that reduces dissatisfaction and switching intentions.