• Title/Summary/Keyword: transition Process

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Sl Transitions in BSCCO Mixed Crystal Thin Films

  • Ahn, Joon-Ho;Yi, Keon-Young;Park, Yong-Pil
    • Transactions on Electrical and Electronic Materials
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    • 제3권2호
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    • pp.20-23
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    • 2002
  • Temperature (T) dependence of the sheet resistance (R$\_$$\square$/) has been investigated an the c-axis oriented thin films of the (Bi2212/Bi2201) mixed crystal with different molar fractions. The R$\_$$\square$/-T superconducting characteristic deteriorated with reduction of the Bi2212 fraction, and almost disappears at 48 mol% where a superconductor-to-insulator transition too k place, with the resistance on the normal state, R$\_$N/, reaching 4.1 kΩka at 80 K. This R$\_$$\square$/ value is close to the universal quantum number, h/(2e)$_2$≡ 6.5 kΩ predicted by the Kosterlitz-Thouless (KT) transition theory. The R$\_$$\square$/-T characteristics of the 48 mol% thin film can be elucidated as a competitive process of KT transition brought about by charge or vortex in the two-dimensional layer structure.

Development of Wave Overtopping-Overflow Transition Model Based on Full-scale Experiments

  • Mase, Hajime;Kim, Sooyoul;Hasegawa, Makoto;Jeong, Jae-Hoon;Yoon, Jong-Sung
    • 한국해양공학회지
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    • 제34권2호
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    • pp.128-135
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    • 2020
  • When high waves and storm surge strike simultaneously, the characteristics of the fluid field change drastically from overtopping according to the wave runup height to overflow through a transition state that combines overtopping and overflows. However, an estimation model or evaluation method has not yet been established because there is not enough engineering data. This study developed a wave overtopping-overflow transition model based on a full-scale experiment involving wave overtopping and overflow transition, which appropriately reproduced the effect of waves or the temporal change in inundation flow. Using this model to perform a calculation for the wave overtopping and overflow transition process under typical circumstances, this study determined the wave runup height and features of the inundation flow under time series changes as an example.

기술통합관계를 이용한 핵심요소기술(CTEs) 선정방안 연구 (A Study on the Selection of Critical Technology Elements(CTEs) Using Integration Relations between Technologies or Components)

  • 배윤호;최석철
    • 한국군사과학기술학회지
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    • 제13권1호
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    • pp.50-56
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    • 2010
  • Military technology transition is the process of transition from the science and technology environment to systems to supply effective weapon systems and support systems to the fighters. In case of technology transition decision, immatured technologies result in increasing acquisition cost and delaying schedule toward the objective system. In this paper, we proposed a method to identify and select critical technology elements by integration relations between technologies or components, for supporting technology transition and risk management of military R&D projects.

동경중심부에 있어서 대가로형성과정에 관한 연구 (A Study on the Transitional Patterns of Main Streets in Tokyo)

  • 배현미
    • 한국조경학회지
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    • 제20권2호
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    • pp.43-61
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    • 1992
  • Recently, people in urban areas ask for the creation of space for amenity and improvement of environmental problems, in such a condition the activation and reformation of city have become an important subject. The basic element of a city structure is the street. Therefore in this study, a transition of street spaces of a city was investigated. This study will be a basis for the planning of urban space in order to realize a comfortable and fascination urban life. In this paper, the study areas chosen were "Ginza", "Kyobashicho", "Nihonbashicho", "Honcho", "Tsukizi", "Hatchoboricho", "Ningyocho", "Ningyocho" which are the central places and business areas of capital Tokyo of Japan. The main streets were chosen for investigative subjects because they were planned as making a division of block in a city planning. Using maps and references the data was illustrated and the investigation was focused on the period from the Edo era to present time. (1) A periodical division for the basis of a street transition. (2) Consideration of methods in a plan and design for street spaces in each period. (3) A special feature and process of a street transition in each period. (4) A structure of a street and a construction form. (5) A classified structure of streets. (6) A process of a transition for each street.

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독일 DLR의 듀얼 벨 노즐 특성 및 핵심 변수 (Characteristics and Key Parameters of Dual Bell Nozzles of the DLR, Germany)

  • 김정훈;허환일
    • 한국항공우주학회지
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    • 제43권11호
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    • pp.952-962
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    • 2015
  • 효율적인 추진기관 개발을 위해 여러 종류의 고도 보정 노즐에 대한 연구가 진행되고 있다. 본 논문에서는 향후 듀얼 벨 노즐 연구를 위한 기초자료로서의 활용을 위해 독일 DLR에서 수행한 연구내용을 바탕으로 듀얼 벨 노즐의 주요 특성을 조사하고 핵심 변수를 도출하였다. DLR은 다양한 실험을 통해 변곡각과 천이 NPR은 비례한다는 것과 확장부 길이와 측하중은 비례하지만 천이 NPR과 천이 지속시간과는 반비례한다는 것을 밝혔다. 성능 예측 과정을 통해 노즐의 형상이 결정될 수 있고 요구 성능에 맞게 변수간의 최적화가 필요하다.

연속고체 표면 위의 단순유체 홑층에 대한 시늉연구 (A Simulational Study of a Simple Fluid Monolayer on a Smooth Solid Surface)

  • 한규광
    • 자연과학논문집
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    • 제10권1호
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    • pp.1-7
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    • 1998
  • 대정준 몬테카를로 시늉을 집중적으로 수행하여 무결정 연속고체 표면 위에 흡착된 Lennard-Jones 유체의 홑층에 대해 덮힘률 $\theta$ ~ 0.8에서 1.8 까지를 연구하였다. 시늉 결과는 최근 흑연위의 알곤 홑층 녹기에 대한 열역학적 실험측정에서 관찰되어졌던 두 단계의 녹음 행태를 뚜렷이 보여 주었다. 본 연구에서 관찰된 녹음 행태는 갑작스러운 밀도 변화 후에 점진적인 상전이로 이루어진다. 홑층 구조에 대한 스냅 사진들은 녹기과정에 어긋나기 짝의 형성과 그 짝의 분리가 연루되어 있다는 것을 가르키고 있다. 계의 크기에 의한 효과를 감안하여, 갑작스러운 밀도 변화는 Kosterlitz, Thouless, Halperin, Nelson, and Young (KTHNY)의 이론과 무관할 것인 반면에, 두 번째의 점진적 전이는 KTHNY 타입의 녹기 상전이일 것이라고 사료된다.

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젊은 나이에 발병한 파킨슨병 환자의 건강-질병 전환 경험 과정 (Health-Illness Transition of Patients with Young-Onset Parkinson's Disease)

  • 김성렬;이숙자
    • 대한간호학회지
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    • 제43권5호
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    • pp.636-648
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    • 2013
  • Purpose: The purpose of this study was to explore the health-illness transition of patients with Young-Onset Parkinson's Disease (YOPD). Methods: From June to November 2011, 17 patients with YOPD who visited a neurologic clinic in a tertiary hospital participated in the study. Data were collected through in-depth interviews and analyzed using the grounded theory of Strauss and Corbin. Results: The core category of the participants' health-illness transition emerged as 'reshaping identity following uncontrollable changes'. The participants' health-illness transition process consisted of six phases in sequence: ego withdrawal, loss of role, frustration, change of thought, modification of life tract, and second life. Although most participants proceeded through the six phases chronologically, some returned to the frustration phase and then took up the remaining phases. Conclusion: The study results provide an in-depth understanding of health-illness transition experiences in the participants. These findings suggest a need to develop appropriate nursing intervention strategies according to the different phases in the health-illness transition of patients with YOPD.

전환연구와 탈추격론의 확장 (Transition Studies and Post Catch-up)

  • 송위진
    • 과학기술학연구
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    • 제16권1호
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    • pp.63-89
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    • 2016
  • 이 글에서는 새롭게 부상하고 있는 전환연구의 관점에서 우리나라 혁신정책담론 중의 하나인 탈추격론을 재해석하는 작업을 수행했다. 탈추격론의 지향점, 주요 연구 대상, 시스템 혁신에 대한 논의를 전환연구의 관점에서 확장하여 지속가능성, 산업과 사회의 공진화, 전환관리 등의 개념을 탈추격론에 도입했다. 이를 통해 탈추격 혁신과 정책은, 기존 시스템의 개선과 최적화가 아니라 탈추격 지속가능 시스템으로의 전환을 지향하고, 사회 환경문제의 해결을 수반하는 탈추격 혁신을 진행해야 하며, 탈추격과 지속가능성의 맹아를 담고 있는 니치를 전환의 관점에서 전략적으로 관리해야 한다는 점을 지적하였다.

간호대학 시뮬레이션 교육의 이행(transition)에 대한 개념 분석 (Transition of Simulation-Based Learning in Nursing Schools: A Concept Analysis)

  • 하이경;방활란;이연희
    • 중환자간호학회지
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    • 제12권2호
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    • pp.50-60
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    • 2019
  • Purpose : The purpose of this study was to identify the attributes, antecedents, and consequences of the transition of simulation-based learning (SBL) in nursing schools. Methods : The study was conducted in accordance with Walker and Avant's conceptual analysis process. We searched MEDLINE, CINAHL, EMBASE, Google Scholar, and RISS (Korean Education and Research Information Service) databases, resulting in nine studies for an in-depth review. Results : The attributes of transition of SBL include (1) preparing for a professional role, (2) practicing in a real clinical setting, and (3) progressing toward expected competency. Antecedents of the concept include novice status, changing roles, clinical experience in controlled settings, and expected competency in the clinical setting. Conclusion : The transition of SBL includes the important feature of progression toward expected competency. Further research is needed to identify graduate nurses' experiences during this transition to establish a strategy for improving it and developing a measurement tool that reflects attributes of the concept.

Fabrication, temperature-dependent local structural and electrical properties of VO2 thin films

  • Jin, Zhenlan;Hwang, In-Hui;Park, Chang-In;Han, Sang-Wook
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.169.2-169.2
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    • 2015
  • $VO_2$ is a well-known a metal-to-insulator-transition (MIT) material, accompanied with a first order structural phase transition near room temperature. Because of the structural phase transition and the MIT occur near a same temperature, there is an ongoing argument whether the MIT is induced by the structural phase transition. $VO_2$ exhibits a relatively weak anti-oxidization ability and can be oxidized to higher-valence oxides (e.g., $V_4$ $O_7$ or $V_2$ $O_5$) when annealed at a high temperature in an oxygen-rich atmosphere. We fabricated $VO_2$ films on $Al_2$ $O_3$ (0001) substrates using a DC magnetron sputtering deposition process with carefully control the $O_2$ percentage in an atmosphere. X-ray diffraction measurements from the films showed only (0l0) peaks with no extra peaks, indicating b-oriented films. The temperature-dependent local structural properties of $VO_2$ films were investigated by using in-situ X-ray absorption fine structure (XAFS) measurements at the V K edge. XAFS revealed that the structural phase transition was occurred nearly $70^{\circ}C$ for heating process and reproducible. Resistance measurements as a function of temperature (R-T) demonstrated that the resistance of $VO_2$ films was changed by a factor of 4 near $75^{\circ}C$ which was higher than $68^{\circ}C$ reported from a $VO_2$ bulk. We will discuss the MIT of $VO_2$ films, comparing with the local structural properties determined by XAFS measurements.

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