• Title/Summary/Keyword: Single Principles

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First-Principles Study on the Electronic Structure of Bulk and Single-Layer Boehmite

  • Son, Seungwook;Kim, Dongwook;Na-Phattalung, Sutassana;Ihm, Jisoon
    • Nano
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    • 제13권12호
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    • pp.1850138.1-1850138.6
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    • 2018
  • Two-dimensional (2D) or layered materials have a great potential for applications in energy storage, catalysis, optoelectronics and gas separation. Fabricating novel 2D or quasi-2D layered materials composed of relatively abundant and inexpensive atomic species is an important issue for practical usage in industry. Here, we suggest the layer-structured AlOOH (Boehmite) as a promising candidate for such applications. Boehmite is a well-known layer-structured material and a single-layer can be exfoliated from the bulk boehmite by breaking the interlayer hydrogen bonding. We study atomic and electronic band structures of both bulk and single-layer boehmite, and also obtain the single-layer exfoliation energy using first-principles calculations.

Principles of Flexible-Use Spectrum Rights

  • Matheson Robert J.
    • Journal of Communications and Networks
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    • 제8권2호
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    • pp.144-150
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    • 2006
  • A serious problem with traditional 'command & control' spectrum management techniques is that they do not easily accommodate new technologies and new services. This paper describes the necessary principles of flexible-use spectrum rights which may allow a wide variety of spectrum uses in a single general-purpose band. Based on the electrospace description of the radio spectrum, these principles allow general aggregation or division of licensed electrospace regions via secondary markets, providing rules for how regulatory limits change under aggregation or division. These flexible-use principles limit transmitter behaviors that tend to create a more difficult operating environment for receivers, while making receivers responsible for handling any remaining interference. The author shows how flexible-use principles could provide a basis for real-world flexible-use frequency bands.

Single-period Stochastic Inventory Problems with Quadratic Costs

  • Song, Moon-Ho
    • 한국국방경영분석학회지
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    • 제5권2호
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    • pp.15-25
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    • 1979
  • Single-period inventory problems such as the newspaper boy problem having quadratic cost functions for both shortages and overage are examined to determine the optimal order level under various principles of choice such as minimum expected cost, aspiration level, and minimax regret. Procedures for finding the optimum order levels are developed for both continuous and discrete demand patterns.

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Single-Chip Microprocessor Control for Switched Reluctance Motor Drive

  • Hao Chen;Ahn, Jin-Woo
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제2B권4호
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    • pp.207-213
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    • 2002
  • The paper introduces a switched reluctance motor drive system based on an 80C31 and an Intel 80C 196KB single-chip microprocessor control. Advance schemes are used in turn-on and turn-off angles with the power converter's main switches during traction and regenerative braking. The principles of traction speed control and braking torque control are given. The hardware and software patterns in the 80c31 and the Intel 80C196KB single-chip microprocessor control system are also presented.

Clinical Application of Chromosomal Microarray for Germline Disorders

  • Chang Ahn Seol
    • Journal of Interdisciplinary Genomics
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    • 제5권2호
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    • pp.24-28
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    • 2023
  • Chromosomal microarray (CMA) is primarily recommended for detecting clinically significant copy number variants (CNVs) in the genetic diagnosis of developmental delay, intellectual disability, autism, and congenital malformations. Prenatal CMA is recommended when a fetus has major congenital malformations. The main principles of CMA can be divided into array comparative genomic hybridization and single-nucleotide polymorphism arrays. In the current CMA platforms, these two principles are combined, and detection of genetic abnormalities including CNVs and absence of heterozygosity is facilitated. In this review, I described practical assessment of CMA testing regarding to laboratory management of CMA, interpretation of CNVs, and special considerations for comprehensive genetic counseling.

단일 빔 음향 집게를 이용한 바이오메디컬 응용 연구 (Single beam acoustic tweezers for biomedical applications)

  • 임해균
    • 한국음향학회지
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    • 제42권5호
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    • pp.452-459
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    • 2023
  • 음파의 힘을 이용하는 음향집게는 나노 단위의 세포외소포에서 밀리미터 단위의 대규모 다세포생 물체까지 다양한 생체 입자를 조작하는 데 사용되는 매우 유용한 도구이다. 해당 분야는 수십년간 점진적인 개발이 이루어지고 있으며, 단일 초음파 빔을 사용하는 단일 빔 음향 집게(Single Beam Acoustic Tweezers, SBAT)기술 또한 세포 및 생물체 정밀 이동 및 분석이 가능한 플랫폼으로 발전했다. 최근 혁신적인 발전으로 SBAT를 이용하여 입자/세포 분리, 단일 세포 변형 기술이 개발되었으며 이로 인해 의공학 분야에서 학문적인 관심을 모으고 있다. 본 종설에서 SBAT기술의 기초 원리와 작동 방법에 대해서 설명하며 그간의 연구를 요약하고 이를 바탕으로 향후 연구에 대해서 전망한다.

고효율, 저손실을 갖는 1단 교류/직류 변환기의 역률제어 (Power Factor Correction of the Single Stage AC/DC Converter with Low Conduction Loss and High Efficiency)

  • 류명효;차영길;최병조;김흥근
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 전력전자학술대회 논문집
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    • pp.418-422
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    • 1998
  • A new single stage AC/DC converter based on the forward converter is proposed. The proposed converter offers both the high power factor and the direct conversion from ac line to dc output voltage. Also, the proposed converter reduces the diode conduction loss, so improves the overall efficiency of the converter, compared with other alternatives. The principles of operation and the simulation results of the proposed converter are presented. A 100 W prototype was built and tested to show the potential of applications of the proposed converter.

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Determination of energetically preferable Au-S contact atomic structure in stretched single-molecule junctions

  • Ko, Kwan Ho
    • EDISON SW 활용 경진대회 논문집
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    • 제3회(2014년)
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    • pp.409-411
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    • 2014
  • Based on the first-principles computations, the nature of the microscopic geometry of the molecule-electrode contacts was addressed. The single-molecule junction was prepared by connecting hexanediothiolate (HDT) to Au(111) electrodes via one, two, and three Au adatoms having coordination number of one (CN1), two (CN2), and, three (CN3), respectively. The contact atomic structure and energy of the stretched Au-HDT-Au junction was observed. The analysis revealed that the contact geometry with lowest coordination number (CN1) is energetically more stable than CN2 and CN3.

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