• 제목/요약/키워드: physical transition

검색결과 622건 처리시간 0.032초

2D transition-metal dichalcogenide (WSe2) doping methods for hydrochloric acid

  • Nam, Hyo-Jik;Park, Jin-Hong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.291.2-291.2
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    • 2016
  • 3D semiconductor material of silicon that is used throughout the semiconductor industry currently faces a physical limitation of the development of semiconductor process technology. The research into the next generation of nano-semiconductor materials such as semiconductor properties superior to replace silicon in order to overcome the physical limitations, such as the 2-dimensional graphene material in 2D transition-metal dichalcogenide (TMD) has been researched. In particular, 2D TMD doping without severely damage of crystal structure is required different conventional methods such as ion implantation in 3D semiconductor device. Here, we study a p-type doping technique on tungsten diselenide (WSe2) for p-channel 2D transistors by adjusting the concentration of hydrochloric acid through Raman spectroscopy and electrical/optical measurements. Where the performance parameters of WSe2 - based electronic device can be properly designed or optimized. (on currents increasing and threshold voltage positive shift.) We expect that our p-doping method will make it possible to successfully integrate future layered semiconductor devices.

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부모역할 전환 후 부모로서의 긴장감이 취업모의 결혼적응에 미치는 영향과 사회적 지지의 완충효과에 관한 연구 (The influence of parental strain on the marital adjustment of employed mothers after transition to the parenthood and the buffering effect of social support)

  • 고선주
    • 한국생활과학회지
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    • 제13권5호
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    • pp.637-646
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    • 2004
  • The purpose of this study is to examine the relation between parental strain and marital adjustment of employed mothers after their transition to the parenthood, and to investigate buffering effect of social support on the relation. The parental strain variables (physical strain and emotional strain) appear to be significant predictors of marital adjustment for employed mothers with first baby. The analysis on interaction effect indicates that social support can be a positive buffering indicator. A comparison reveals that mothers with high physical strain have significantly higher marital adjustment than those with low strain. But in the context of high social support, the difference of marital adjustment between the two mothers is reduced.

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취업부부의 부모기 전이후 부모로서의 긴장감, 지배감, 성역할태도와 결혼적응 (Parental strain, mastery, sex role attitude, and dyadic adjustment after the transition to parenthood in the dual earner family)

  • 고선주
    • 대한가정학회지
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    • 제35권5호
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    • pp.17-32
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    • 1997
  • The purpose of this study is to explore parental strain, mastery, sex role attitude and dyadic adjustment after the transition to parenthood in dual earner family. Using couple data from a sample of 284 dual earner couple, pair t-test, multiple regression analysis, one was ANOVA was used. Major findings were as follows. 1) There were differences between wives and husbands in dyadic adjustment, physical strain, mastery, sex role attitude. Specially, couples experience more emotional strain than physical strain, and wives experience more parental strain than husbands. 2) Couple's parental strain is considered personal attribution rather than family one, but mastery is different. 3) Couple's psychological variables have an effect on the dyadic adjustment sores, especially husband's sex role attitude influences own dyadic adjustment and wife's dyadic adjustment. Wife's mastery also own dyadic adjustment and husband's dyadic adujstment.

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Generation of Maxwell Displacement Current Across Single monolayers due to Phase transition

  • Mitsumasa Iwamoto;Wu, Chen-Xu
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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    • pp.6.1-10
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    • 1996
  • Starting from the Debye theory of rotational Brownian motion equation, we derive an expression for explaining the generation of Maxwell displacement current (MDC) across single monolayers on a material surface. The orientational order parameter and the dielectric relaxation the of monolayers are derived. Based on fille analyses developed here, we examine the MDC across phospholipid monolayers with thermal stimulation due to the change in the spontaneous polarization, and the generation of MDC from 4-cyano-4\`-5-alkayl-biphenyl(5CB) Langmuir-film at the onset of transition by monolayer compression

장애청소년의 전환프로그램 : 연구 동향 분석과 체계적 고찰 (Transition Program for Youth With Disabilities: Research Trend Analysis and Systematic Review)

  • 안수빈;박혜연
    • 재활치료과학
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    • 제11권3호
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    • pp.23-36
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    • 2022
  • 목적 : 본 연구는 전환프로그램 연구동향과 장애청소년을 대상으로 국내외 전환프로그램의 중재 및 효과를 체계적으로 분석함으로써 학교 및 지역사회 관련 기관들과 협력하여 성인생활의 모든 측면을 포함할 수 있는 중재 전략에 대한 기초자료를 제공하는 것을 목적으로 한다. 연구방법 : 학술연구정보서비스(Research Information Sharing Service: RISS), Pubmed, Web of Science(WoS) 데이터베이스를 사용하여 2006년부터 2021년까지의 게재된 논문을 검색하였다. 주요 검색어는 'Disability' AND ('Adolescents' OR 'Young adult') AND ('Transition education' OR 'Transition program')를 사용하였다. 최종적으로 7편의 국내외 논문을 본 연구의 분석 대상으로 선정하여 전문을 검토하였다. 또한, WoS(Web of Science) 플랫폼과 VOSviewer(version 1.6.16, CWTS, Netherlands, 2020) 프로그램을 이용하여 키워드와 국가 관계를 분석하고 시각화하였다. 결과 : 7개의 논문에서 참여한 대상자를 유형별로 분석한 결과, 대상자는 ASD, ADHD, ID, DD, physical disability 총 5가지로 분류되었다. 중재에 사용된 영역은 크게 직업(학업), 자기관리(시간), 상호작용(대인관계, 의사소통) 3가지 범주로 혼합되어 실시되었다. 중재 결과 7편 중 1편을 제외하고는 사회성 및 적응, 삶의 질, 일상생활활동 세 가지 분류 중 적어도 하나 이상의 부분에서 유의미한 향상을 보였다. 결론 : 본 연구는 전환프로그램의 연구동향을 파악하면서 프로그램의 적용과 그 효과를 정리하여 다양한 전문가와의 교류하는 방향성을 제시하는 동시에 단편적인 측면이 아닌 성인생활의 모든 측면을 확대하는 기초자료로 활용될 수 있을 것이다.

Tunable Metal-Insulator Phase Transition in $VO_2$ Nanowires

  • Seong, Won-Kyung;Lee, Ji-Yeong;Moon, Myoung-Woon;Lee, Kwang-Ryeol
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.385-385
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    • 2012
  • Understanding the thermodynamics and structural transformation during the Metal-Insulator Transition (MIT) is critical to better understand the underlying physical origin of phase transition in the vanadiumdioxide ($VO_2$). Here, through the temperature-dependent in-situ high resolutiontransmission electron microscopy (HR-TEM), and systematic electrical transport study, we have shown that the tunable MIT transition of $VO_2$ nanowires is strongly affected by interplay between strain and domain nucleation by ion beam irradiation. Surprsingly, we have also observed that the $VO_2$ rutile (R) metallic phase could form directly in a strain-induced metastable monoclinic (M2) phase. These insights open the door toward more systematic approaches to synthesis for $VO_2$ nanostructures in desired phase and to use for applications including ultrafast optical switching, smart window, metamaterial, resistance RAM and synapse devices.

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Bonding And Anti-bonding Nature of Magnetic Semiconductor Thin Film of Fe(TCNQ:tetracyanoquinodimethane)

  • Jo, Junhyeon;Jin, Mi-jin;Park, Jungmin;Modepalli, Vijayakumar;Yoo, Jung-Woo
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.294-294
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    • 2014
  • Developing magnetic thin films with desirable physical properties is a key step to promote research in spintronics. Organic-based magnetic material is a relatively new kind of materials which has magnetic properties in a molecular and microscopic level. These materials have been constructed by the coordination between 3d transition metal and organic materials producing long-range magnetic orders with a relatively high transition temperature. However, these materials were mostly synthesized as a form of powder, which is difficult to study for their physical properties as well as apply for electronic/spintronic devices. In this study, we have employed physical vapor deposition (PVD) to develop a new organic-based hybrid magnetic film that is achieved by the coordination of Fe and tetracyanoquinodimethane (TCNQ). The IR spectra of the grown film show modified CN vibration modes in TCNQ, which suggest a strong bonding between Fe and TCNQ. The thin film has both ferromagnetic and semiconducting behaviors, which is suitable for molecular spintronic applications. The high resolution photoemission (HRPES) spectra also show shift of 1s peak point of nitrogen and the carbon 1s peaks display traces of charge transfer from Fe to TCNQ as well as shake-up features, which suggest strong bonding and anti-bonding nature of coordination between Fe and TCNQ.

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87Rb D1 전이선에서 원자결맞음을 이용한 비선형 광자기 효과 신호의 특성 (The characteristics of nonlinear magneto-optical effect based on coherent population trapping in the D1 line of Rh atoms)

  • 이림;문한섭;김중복
    • 한국광학회지
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    • 제17권1호
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    • pp.1-6
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    • 2006
  • 우리는 6.7 kPa의 네온 버퍼가스가 포함된 루비듐 증기셀을 이용하여 $^{87}Rb$원자 $D_1$ 전이선에서 레이저의 세기, 증기 셀의 온도, 전이 선에 따른 비선형 광자기 신호(NMOE)의 특성을 조사하였다. 비선형 광자기 신호는 레이저의 세기와 증기셀의 온도가 증가함에 따라 F=2$\to$F'=2 전이선에서는 광자기 신호의 크기와 선폭이 증가하였지만, F=2$\to$F'=1 전이선에서는 확대 없이 신호의 크기만 증가됨으로써 자장 측정 민감도가 향상되는 것을 확인하였으며, 이러한 효과를 자기부준위 사이에서의 원자결맞음 구도의 차이로 설명하였다. 관측된 최적 조건에서 자기장변화에 대한 민감도는 $70pT/\sqrt{Hz}$ 이하로 계산되었다.

Non-stoichiometry-induced metal-to-insulator transition in nickelate thin films grown by pulsed laser deposition

  • Lee, Jongmin;Choi, Kyoung Soon;Lee, Tae Kwon;Jeong, Il-Seok;Kim, Sangmo;Song, Jaesun;Bark, Chung Wung;Lee, Joo-Hyoung;Jung, Jong Hoon;Lee, Jouhahn;Kim, Tae Heon;Lee, Sanghan
    • Current Applied Physics
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    • 제18권12호
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    • pp.1577-1582
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    • 2018
  • While controlling the cation contents in perovskite rare-earth nickelate thin films, a metal-to-insulator phase transition is reported. Systematic control of cation stoichiometry has been achieved by manipulating the irradiation of excimer laser in pulsed laser deposition. Two rare-earth nickelate bilayer thin-film heterostructures with the controlled cation stoichiometry (i.e. stoichiometric and Ni-excessive) have been fabricated. It is found that the Ni-excessive nickelate film is structurally less dense than the stoichiometric film, albeit both of them are epitaxial and coherent with respect to the underlying substrate. More interestingly, as a temperature decreases, a metal-to-insulator transition is only observed in the Ni-excessive nickelate films, which can be associated with the enhanced disproportionation of the Ni charge valence. Based on our theoretical results, possible origins (e.g. anti-site defects) of the low-temperature insulating state are discussed with the need of future work for deeper understanding. Our work can be utilized to realize unusual physical phenomena (e.g. metal-to-insulator phase transitions) in complex oxide films by manipulating the chemical stoichiometry in pulsed laser deposition.