• 제목/요약/키워드: research specific field

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초전도 결정의 저온 비열 점프의 자기장 의존성 (Magnetic Field Dependence of Low Temperature Specific Heat Jump in Superconducting Crystal)

  • 김철호
    • 한국재료학회지
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    • 제21권2호
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    • pp.73-77
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    • 2011
  • Specific heat of a crystal is the sum of electronic specific heat, which is the specific heat of conduction electrons, and lattice specific heat, which is the specific heat of the lattice. Since properties such as crystal structure and Debye temperature do not change even in the superconducting state, the lattice specific heat may remain unchanged between the normal and the superconducting state. The difference of specific heat between the normal and superconducting state may be caused only by the electronic specific heat difference between the normal and superconducting states. Critical temperature, at which transition occurs, becomes lower than $T_{c0}$ under the influence of a magnetic field. It is well known that specific heat also changes abruptly at this critical temperature, but magnetic field dependence of jump of specific heat has not yet been developed theoretically. In this paper, specific heat jump of superconducting crystals at low temperature is derived as an explicit function of applied magnetic field H by using the thermodynamic relations of A. C. Rose-Innes and E. H. Rhoderick. The derived specific heat jump is compared with experimental data for superconducting crystals of $MgCNi_3$, $LiTi_2O_4$ and $Nd_{0.5}Ca_{0.5}MnO_3$. Our specific heat jump function well explains the jump up or down phenomena of superconducting crystals.

Characteristics of Specific Absorption Rate (SAR) in Electromagnetic (EM) Dosimetry

  • Hwang, Sun-Tae;Choi, Kil-Oung
    • Journal of Radiation Protection and Research
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    • 제25권2호
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    • pp.109-114
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    • 2000
  • The SI unit of specific absorption rate (SAR) in W/kg in the electromagnetic (EM) field as non-ionizing radiation is exactly same as the SI unit of absorbed dose rate in Gy/s in the ionizing radiation field. The SI unit of both physical quantities can be expressed in $[m^{\cdot}s^{-3}]$. Where, the unit of absorbed dose, Gy stands for Gray. In EM biological interactions, the SAR equations are derived and the characteristics of EM field energy absorption in terms of the SAR are discussed and described on the mathematical basis.

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Review on ICF-related Research Trends in Korean Clinical Field

  • Song, Ju-Min
    • 대한물리의학회지
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    • 제16권4호
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    • pp.33-44
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    • 2021
  • PURPOSE: This study analyzed the research trends related to the International Classification of Functioning, Disability, and Health (ICF) to suggest an ICF utilization plan in the Korean clinical field. METHODS: In the RISS, KISS, NSDL, and PubMed databases, papers published between 2016 and July 2021 were collected by applying the search terms, 'ICF', 'international classification of functioning, disability and health', 'clinic', 'patient', and 'diagno'. The 44 papers selected were classified according to the analysis criteria, and the frequency and percentage were calculated. RESULTS: In domestic clinical trials, the frequency of ICF-related studies was in the order of physical therapy (n = 19) and occupational therapy (n = 14). The frequency of each study subject was observed in the order of studies related to a specific disease (n = 34) and prior studies (n = 7). The research topics were in the order of studies using ICF as a measurement tool (n = 21) and case studies with patients with specific diseases (n = 11). There were 18 studies using ICF codes and 14 papers applying the ICF domains. CONCLUSION: Over the last five years, ICF-related research in the domestic clinical field targeted patients with more diverse diseases in more expertise fields. Research for the unification of terms should be conducted for communication among various experts in clinical practice. To promote the use of ICF in the clinical field, it will be necessary to conduct research, such as the unification of terms, standardized education, development of ICF casebook, and development of ICF coding programs and guidelines.

Abundance of the Toxic Dinoflagellate Alexandrium catenella in Jinhae Bay, Korea as Measured by Specific Real-time PCR Probe

  • Park, Tae-Gyu;Kang, Yang-Soon;Park, Young-Tae
    • Fisheries and Aquatic Sciences
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    • 제12권3호
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    • pp.227-235
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    • 2009
  • The marine toxic dinoflagellate Alexandrium catenella has been implicated in numerous paralytic shellfish poisoning (PSP) events in many countries. Due to difficulties in rapidly identifying A. catenella, field-based study of this species has been problematic. The present study developed a TaqMan format A. catenella-specific probe for real-time PCR assay (specific to Korean genotype) based on LSU rDNA sequence information for studying geographic and temporal distribution of the species in surface sediments and water columns of Jinhae Bay, Korea. The field survey from 2007 to 2008 revealed that A. catenella occurred in most seasons at low densities, mostly below 1 cell $mL^{-1}$, and was more abundant in spring (maximum cell density of 2 cells $mL^{-1}$) when shellfish exceed the quarantine toxin level for PSP toxins in Jinhae Bay.

Probabilistic Model and Analysis of a Conventional Preinstalled Mine Field Defense

  • Lee, Young-Uhn
    • 한국국방경영분석학회지
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    • 제6권2호
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    • pp.151-184
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    • 1980
  • Simple models for a defense consisting of a preinstalled mine field possibly defended by an anti-tank weapon are derived and analyzed. This paper uses a special Poisson process to model the one or two positions of mines in the mine field. The duel between the anti-tank weapon and offensive tanks crossing the field is modeled with a continuous time Markov chain. Some algebraic solutions and numerical results are obtained for specific scenarios.

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직류철도차량에 대한 자계측정 및 분석 (Measurement and Analysis of Electromagnetic field for DC electric railway train)

  • 장동욱;김민철;이장무;한문섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.1637-1639
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    • 2005
  • The measurement of magnetic field is performed about DC and AC magnetic field in test track of depot. The test point is cap, on the converter/inverter box, on the traction motor, on the APSE and on the line filter, the height of measurement is bottom and 50 cm height. In case of AC magnetic field, the selected specific frequency is measured on the converter/inverter box. The AC magnetic field is checked and analysis through RS-232C and notebook PC. The DC magnetic field is measured by using the Hall Probe, test result is saved and analysis by PXI system. On the line filter, the maximum value is 1.4 mT in case of DC magnetic field and 0.044 mT in case of AC magnetic field at 50 Hz.

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복잡한 지형상에서 실시간 피폭해석 시스템 검증 (Validation of a Real-Time Dose Assessment System over Complex Terrain)

  • 서경석;김은한;황원태;최영길;한문희;정성태
    • Journal of Radiation Protection and Research
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    • 제24권1호
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    • pp.31-38
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    • 1999
  • 원자력시설의 사고시 신속한 방재대책 결정지원 체계를 수립하기 위하여 실시간 방사선 피폭해석 시스템(FADAS : Following Accident Dose Assessment System)을 개발하였다. 개발된 시스템의 정확도 향상 및 국내 부지 특성자료의 모수화를 위하여 복잡한 지형상에 위치한 영광 원자력발전소 주변에서 야외 확산실험이 수행되었다. 확산실험을 통하여 얻어진 바람의 평균 및 난류장 성분은 부지 특성별 변수로 실시간 방사선 피폭해석 시스템에 반영되었다. 확산모형의 계산결과와 실험을 통하여 관측된 추적자 가스의 농도분포를 상호 비교한 바 어느 정도 일치하고 있었다. 개발된 시스템은 현재 구축중인 국가 규모의 비상대응지원체제에 기본 모듈로서 활용 중에 있으며 지속적인 확산실험을 통하여 부지 특성 변수들이 반영된 확산모형을 개선할 예정이다.

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Research Ethics in the Aviation Service Industry

  • Soyeon PARK
    • 연구윤리
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    • 제5권1호
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    • pp.7-11
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    • 2024
  • Purpose: This study seeks to discuss research ethics, not only the academic honesty and sincerity that researchers who study aviation services academically should have, but also the direction of the moral aspects that are fundamentally required as researchers. Additionally, this study seeks to examine the realistic problems of research related to the aviation service industry, a field of social science. Lastly, focusing on research ethics in the aviation service field, we will look at the theoretical background and the problems in the actual research field, and draw implications based on this. Research design, data and methodology: This study conducted an exploratory study through a selection process based on research ethics topics and research ethics related to the aviation service industry. Results: Efforts to systematize research ethics in research areas related to the aviation service industry, which is a field of social science, require efforts to expand the scope of systematization of research ethics related to the aviation service industry by referring to systemization efforts in other academic fields. In addition, specific systemization efforts will be needed through cooperation between universities, research institutes, and academic organizations. Also, concrete systematization efforts will be needed through cooperation between universities and academic organizations.

Characteristics of P-channel SOI LDMOS Transistor with Tapered Field Oxides

  • Kim, Jong-Dae;Kim, Sang-Gi;Roh, Tae-Moon;Park, Hoon-Soo;Koo, Jin-Gun;Kim, Dae-Yong
    • ETRI Journal
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    • 제21권3호
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    • pp.22-28
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    • 1999
  • A new tapered TEOS oxide technique has been developed to use field oxide of the power integrated circuits. It provides better uniformity of less than 3 % and reproducibility. On-resistance of P-channel RESURE (REduced SURface Field) LDMOS transistors has been optimized and improved by using a novel simulation and tapered TEOS field oxide on the drift region of the devices. With the similar breakdown voltage, at $V_{gs}$=-0.5V, the specific on-resistance of the LDMOS with the tapered field oxide is about $31.5{\Omega}{\cdot}cm^2$, while that of the LDMOS with the conventional field oxide is about $57m{\Omega}{\cdot}cm^2$.

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Development of Image Processing Software for Satellite Data

  • Chi, Kwang-Hoon;Suh, Jae-Young;Han, Jong-Kyu
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.361-369
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    • 1998
  • Recently, the improvement of on-board satellite sensors covering hyperspectral image sensors, high spatial resolution sensors provide data on earth in diverse aspect. The application field relating remotely sensed data also varies depending on what type of job one wants. The various resolution of sensors from low to extremely high is also available on the market with a user defined specific location. The expense to purchase remote sensed data is going down compare to the cost it need past few years ago in terms of research or private use. Now, the satellite remote sensed data is used on the field of forecasting, forestry, agriculture, urban reconstruction, geology, or other research field in order to extract meaningful information by applying special techniques of image processing. There are many image processing packages available worldwide and one common aspect is that they are expensive. There need to be a advanced satellite data processing package for people who can not afford commercial packages to apply special remote sensing techniques on their data and produce valued-added product. The study was carried out with the purpose of developing a special satellite data processing package which covers almost every satellite produced data with normal image processing functions and also special functions needed on specific research field with friendly graphical user interface (GUI). And for the people with any background of remote sensing with windows platform.

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