• 제목/요약/키워드: Novel phenomena

검색결과 144건 처리시간 0.025초

STATISTICAL PHYSICS APPROACH TO BIOLOGICAL PHENOMENA

  • Sung, Wokyng
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1996년도 정기총회 및 학술발표회
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    • pp.7-7
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    • 1996
  • A new trend that emerges at the turn of the century is the physical approach to biological phenomena. It is expected that biology provides novel materials for condensed matter physics and, most importantly, a revolutionary paradigm for physics at large. On the other hand, physics, if properly extended, is expected to provide systematic and quantitative understanding of biological phenomena, and multitude of biotechnological applications. (omitted)

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Self-Pulsation in Multisection Distributed Feedback Laser Diode with a Novel Dual Grating Structure

  • Park, Kyung-Hyun;Leem, Young-Ahn;Yee, Dae-Su;Baek, Yong-Soon;Kim, Dong-Churl;Kim, Sung-Bock;Sim, Eun-Deok
    • ETRI Journal
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    • 제25권3호
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    • pp.149-155
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    • 2003
  • A self-pulsating multisection distributed-feedback laser diode (DFB LD) can potentially realize all-optical clock extraction. This device generally consists of three sections, two DFB sections and one waveguide section. The most important variable in this device is detuning, which is the relative spectral position between the stop bands of two DFB sections. We fabricated a novel structure in which two gratings were located one over and one under the active layers. Each grating structure was independently defined in processing so that detuning, which is the prerequisite for self-pulsation, could be easily controlled. Observing various self-pulsating phenomena in these devices under several detuning conditions, we characterized the phenomena as dispersive Q-switching, mode beating, and self-mode-locking.

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A Novel Body-tied Silicon-On-Insulator(SOI) n-channel Metal-Oxide-Semiconductor Field-Effect Transistor with Grounded Body Electrode

  • Kang, Won-Gu;Lyu, Jong-Son;Yoo, Hyung-Joun
    • ETRI Journal
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    • 제17권4호
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    • pp.1-12
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    • 1996
  • A novel body-tied silicon-on-insulator(SOI) n-channel metal-oxide-semiconductor field-effect transistor with grounded body electrode named GBSOI nMOSFET has been developed by wafer bonding and etch-back technology. It has no floating body effect such as kink phenomena on the drain current curves, single-transistor latch and drain current overshoot inherent in a normal SOI device with floating body. We have characterized the interface trap density, kink phenomena on the drain current ($I_{DS}-V_{DS}$) curves, substrate resistance effect on the $I_{DS}-V_{DS}$ curves, subthreshold current characteristics and single transistor latch of these transistors. We have confirmed that the GBSOI structure is suitable for high-speed and low-voltage VLSI circuits.

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A refined HSDT for bending and dynamic analysis of FGM plates

  • Zaoui, Fatima Zohra;Tounsi, Abdelouahed;Ouinas, Djamel;Olay, Jaime A. Vina
    • Structural Engineering and Mechanics
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    • 제74권1호
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    • pp.105-119
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    • 2020
  • In this work, a novel higher-order shear deformation theory (HSDT) for static and free vibration analysis of functionally graded (FG) plates is proposed. Unlike the conventional HSDTs, the proposed theory has a novel displacement field which includes undetermined integral terms and contains fewer unknowns. Equations of motion are obtained by using Hamilton's principle. Analytical solutions for the bending and dynamic investigation are determined for simply supported FG plates. The computed results are compared with 3D and quasi-3D solutions and those provided by other plate theories. Numerical results demonstrate that the proposed HSDT can achieve the same accuracy of the conventional HSDTs which have more number of variables.

Probing and Control of Surface Polarization Phenomena in Molecular Films for Organic Electronics

  • Iwamoto, Mitsumasa
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.3-4
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    • 2007
  • Orientational ordering of polar molecules and excess charges at the interface are main origins of surface polarization. For organic electronics, probing and control of these two surface polarization phenomena are key issues. In this presentation, I report a novel electrical measurement that can directly probe orientational dipolar motion in surface monolayers by Maxwell-displacement-current, and also report a novel optical technique that allows carrier motions in organic materials by measuring the optical second harmonic signals activated by the electric field. Then I discuss how the control of dipolar motions and carrier motions are linked to organic electronics applications such as organic field effect transistors.

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Molecular Dynamics Simulation for Size-Dependent Properties and Various Nanoscale Phenomena

  • Seungho;Joon Sik;Young Ki;Sung San;Jung Soo
    • International Journal of Precision Engineering and Manufacturing
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    • 제5권4호
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    • pp.28-35
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    • 2004
  • Stimulated by novel phenomena observed in molecular aggregates, recent developments in engineering fields of microscopic scales are creating tremendous opportunities for future nanotechnology-based applications. Investigation in the field involves sub-nanosecond or sub-micrometer interactions between extremely small systems, but researches, to date in these physical extremes have been quite limited. Here, we shed light on some of nanoscale phenomena using molecular dynamics simulation: visualization of various phenomena of nanoscales and exploration of size-dependent mechanical properties.

Novel properties of erbium-silicided n-type Schottky barrier metal-oxide-semiconductor field-effect-transistors

  • Jang, Moon-Gyu;Kim, Yark-Yeon;Shin, Jae-Heon;Lee, Seong-Jae;Park, Kyoung-Wan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제4권2호
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    • pp.94-99
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    • 2004
  • silicided 50-nm-gate-length n-type Schottky barrier metal-oxide-semiconductor field-effect-transistors (SB-MOSFETs) with 5 nm gate oxide thickness are manufactured. The saturation current is $120{\mu}A/{\mu}m$ and on/off-current ratio is higher than $10^5$ with low leakage current less than $10{\mu}A/{\mu}m$. Novel phenomena of this device are discussed. The increase of tunneling current with the increase of drain voltage is explained using drain induced Schottky barrier thickness thinning effect. The abnormal increase of drain current with the decrease of gate voltage is explained by hole carrier injection from drain into channel. The mechanism of threshold voltage increase in SB-MOSFETs is discussed. Based on the extracted model parameters, the performance of 10-nm-gate-length SB-MOSFETs is predicted. The results show that the subthreshold swing value can be lower than 60 mV/decade.

Embodiment of all-optical switching phenomena on a GaAs waveguide

  • 이상재
    • 센서학회지
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    • 제5권5호
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    • pp.85-95
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    • 1996
  • Based on the transmission of coupled gap solitons in nonlinear periodic media, we present an all-optical switching scheme which has a novel architecture and principle. The proposed switch with an extremely small switching element can be realized on a semiconductor waveguide. We here investigate the switching performance with a GaAs waveguide in order to give criteria for the experimental realization of the all-optical switching phenomena. We also suggest a variation of an index-matching scheme to solve the technical problem such as the input-energy coupling into a periodic waveguide.

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데이터베이스의 과학에 대한 고찰 및 연구 사례 분석 (A Review of Science of Databases and Analysis of Its Case Studies)

  • 서영균;김종욱
    • 정보과학회 논문지
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    • 제43권2호
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    • pp.237-245
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    • 2016
  • 본 논문은 새로운 연구 분야인, 데이터베이스의 과학을 소개하고 그에 대한 연구 사례들을 분석한다. 데이터베이스에 대한 과학은 다중의 데이터베이스 관리 시스템에서 교차되어 관찰되는 흥미로운 현상을 더 잘 이해하는데 목적이 있다. 그동안 데이터베이스 연구 분야에서 수학적이고 공학적인 연구가 주류를 이루어 온데 반해, 데이터베이스 관리 시스템을 잘 이해할 수 있는 과학적인 연구는 다소 덜 주목받아 왔다. 사실 과학적인 연구는 질의 최적화 및 트랜잭션 처리에 대한 더 깊은 이해를 이끌어 내어 궁극적으로 기존 데이터베이스 관리 시스템의 성능을 개선하는데 간접적으로 기여할 수 있다. 데이터베이스에 대한 과학 분야는 현재까지 서로 다른 데이터베이스 관리 시스템으로부터 관찰된 다수의 현상 사례들을 연구하고 발견된 결과를 토대로 다수의 공학적 함의를 제공해 왔다. 본 논문은 데이터베이스에 대한 과학적, 실증적 연구 방법론을 살펴보고, 이를 지원하는 사이버 인프라를 소개한다. 이어서 지금까지 다뤄진 현상 연구 사례들을 복개하고 각 현상의 설명을 위해 제안된 실증적으로 검증된 구조 인과 모델을 논의한다. 끝으로, 연구 사례들을 종합적으로 분석 한 후, 관심 연구자들을 위한 향후 연구 방향을 제시한다.

등각사상법과 유한요소법을 이용한 2단계 최적설계법 (A Novel Optimization Procedure Utilizing the Conformal Transformation Method)

  • 임지원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 학술대회 논문집 전문대학교육위원
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    • pp.7-12
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    • 2001
  • A large number of methods for the design optimization have been proposed in recent years. However, it is not easy to apply these methods to practical use because of many iterations. So, in the design optimization, physical and engineering investigation of the given model are very important, which results in an overall increase in the optimization speed. This paper describes a novel optimization procedure utilizing the conformal transformation method. This approach consists of two phases and has the advantage of grasping the physical phenomena of the model easily. Some numerical results that demonstrate the validity of the proposed method are also presented.

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