• 제목/요약/키워드: internal energy

검색결과 2,161건 처리시간 0.041초

이중에너지 컴퓨터 단층촬영을 통해 진단된 폐의 미세혈관종양색전증 (Microvascular Pulmonary Tumor Embolism Detected by Perfusion Images of Dual-Energy Computed Tomography)

  • 옥태진;조민수;장선주;박한승;박환성;박세정;윤신교;이호수;백충희;김광운;김달용;홍윤기;서준범;오연목
    • Tuberculosis and Respiratory Diseases
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    • 제72권1호
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    • pp.63-67
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    • 2012
  • Although advances in multi-detector computed tomography (CT) technique make it possible to evaluate peripheral subsegmental pulmonary arteries, several studies have reported that small peripheral embolisms may still be missed. Recently, some reports demonstrated that dual-energy CT improved the capability to detect peripheral pulmonary embolism. We report a case of lymphoma presenting as disseminated microvascular pulmonary tumor embolism, detected by perfusion images using dual energy CT.

내부 유동유체에 의한 송수관의 동적안정성과 진동제어 (Vibration Control and Dynamic Stability of Pipes by means of Internal Flowing Fluid)

  • 류봉조;정승호;엄재섭
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.550-554
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    • 1995
  • The present paper deals with the dynamic stability and vibration suppression of a cantilevered flexible pipe with a concetrated mass under an internal fluid flow. The equations of motion are derived by energy expressions using Hamilton's pronciple, and some analytical results using Galerkin's method are presented. Finally, the vibration suppression technique by means of an internal fluid flow is demonstrated experimentally.

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대한해협주변 내부조석의 계절적 변동성: 3차원 고해상도 모델 연구 (Seasonal Variability of Internal Tides around the Korea Strait: 3-D High-resolution Model Simulation)

  • 이현정;이호진;박재훈;하호경
    • Ocean and Polar Research
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    • 제36권1호
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    • pp.1-12
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    • 2014
  • This study investigates spatial and temporal variations in the generation and propagation of internal tides around the Korea Strait using a three-dimensional high resolution model (Regional Ocean Modeling System; ROMS). The model results were verified through comparison with in-situ current measurements from an array of 12 acoustic Doppler current profilers (ADCPs) deployed in the Korea Strait. Fluxes and distributions of internal tidal energy were calculated using simulation results gathered in February and August. Our analyses reveal that energetic semidiurnal internal tides are generated in a region around the Korea Strait shelf break ($35.5^{\circ}N$, $130^{\circ}{\sim}130.5^{\circ}E$), where the strong cross-slope semidiurnal barotropic tidal currents interact with a sudden topographical change. The semidiurnal internal tidal energy generated in summer displays values about twice as large as values in winter. Propagation of semidiurnal internal tides also reveals seasonal variability. In February, most of the semidiurnal internal tides propagate only into the open basin of the East Sea due to weak stratification in the Korea Strait, which inhibits their southwestward propagation. In August, they propagate southwestward to $35.2^{\circ}N$ along the western channel of the Korea Strait because of strong stratification. In addition, semidiurnal internal tides generated in a region west of Tsushima Island are found to propagate to the coast of Busan. This can be explained by the intensified stratification due to the strong intrusion of bottom cold water in the western channel of the Korea Strait during summer.

A Shared Compliant Control Scheme based on Internal Model Control

  • Ahn, Sung-Ho;Jin, Jae-Hyun;Park, Byung-Suk;Yoon, Ji-Sup
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1571-1574
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    • 2003
  • A shared compliant control scheme based on IMC is proposed for the position-force force reflecting control system. The controller of the slave manipulator is designed by IMC method for the open loop unstable plant. The compliant control is implemented by first order low pass filter. In the proposed scheme, the slave manipulator well tracks the position of the master manipulator in free space and the compliance of the slave manipulator is autonomously controlled in contact condition. The simulation results show that the excellence of the proposed controller.

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초소형 전자기 유도방식 에너지 하베스터용 연성 박막 다적층 평판 코일 설계 및 제작 (Design and Fabrication of Flexible Thin Multilayered Planar Coil for Micro Electromagnetic Induction Energy Harvester)

  • 박현철
    • 한국정밀공학회지
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    • 제33권7호
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    • pp.601-606
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    • 2016
  • In this paper, an energy harvester is developed that has advantages regarding piezoelectric noise minimization, mass production, and an easily available environmental energy source, electromagnetic induction, as well as low-frequency bandwidth and high amplitude. A process for fabricating a three-dimensional multilayered planar coil using micro-electro-mechanical systems (MEMS) on a flexible printed circuit board FPCB is introduced. Optimal shape and size were calculated via internal resistance and inductance, and a prototype was fabricated through the MEMS procedure while considering the possibility of mass production. Although the internal resistance matched the designed value, the electromotive force generated did not reach the intended amount. The main reason for the decrease in efficiency was the low area of coil outskirt exposed to the magnetic field while there was relative motion between the magnet and the coil.

물속에서의 지방족 및 방향족 탄화수소들의 열역학적 성질 (Thermodynamic Properties of Aliphatic and Aromatic Hydrocarbons in Liquid Water)

  • 성용길;김은식;전무식
    • 대한화학회지
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    • 제16권5호
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    • pp.265-270
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    • 1972
  • 지방족 및 방향족 탄화수소의 수용액을 Jhon 등이 제창한 liquid water의 significant structure theory 를 이용하여 연구하였으며 Helmholtz free energy, internal energy, entropy, heat capacity 등의 열역학적 성질을 계산하였다. 계산결과는 문헌에 발표된 실험치와 잘 일치됨을 볼 수 있다

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9.9MW급 바이오매스 열병합발전 타당성 연구 (The Feasibility Analysis of 9.9 MW Biomass Cogeneration System)

  • 최재영;설용건
    • 신재생에너지
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    • 제10권2호
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    • pp.40-47
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    • 2014
  • This study is intended to analyze the appropriate scope for 9.9MW biomass cogeneration, feasibility and sensitivity according to changing market situation. In the study, the heat load is classified into three types to predict heat sales and find out the appropriate scope of thermal business that is operated in CHP 34.42 Gcal/h, PLBwg 70 Gcal/h of cogeneration. the feasibility is estimated based on internal rate of return (IRR) and net present value(NPV). the sensitivity is analyzed in terms of biomass fuel cost, unit price of heating cost, investment cost, SMP unit price and REC unit price.

평판에 충동하는 사각봉의 소성응력해석 (An Analysis of Plastic Stress in Square Bar Impacting Plate)

  • 김기선;조재웅;최두석
    • 한국자동차공학회논문집
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    • 제12권5호
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    • pp.198-204
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    • 2004
  • Dynamic fracture is investigated in plate applied by impacting bar. Numerical simulations of the experiments are made by using a finite element method(FEM) code, LS-DYNA. The eroding surface-to-surface contact allows between impacting bar and impacted plate. The occurrence of hourglass deformations in an analysis can invalidate results and hourglass energy is minimized to obtain the good accuracy of result. Total, internal and kinetic energies, von Mises plastic stress and X,Y,Z velocities of impacting bar are analyzed in this study.

전면형 이중외피의 절기별 운용성능 분석 (Analysis for Seasonal Operation Performance of Multistory Facade)

  • 임혜진;조수;성욱주;임상훈;한찬훈
    • 설비공학논문집
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    • 제24권2호
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    • pp.111-120
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    • 2012
  • In this study, to present the data in the internal thermal condition of Double skin facade were measured internal temperature and inlet and outlet openings wind speed of double skin facade. Measurements were similar to temperatures in the upper double skin facade. Especially in summer, temperature stratification is through to be unfulfilled seamlessly despite inlet and outlet openings open. Double skin facade inlet and outlet openings of the air flow rate was slower outlet openings of the air flow rate than inlet openings of the air flow rate.

Development of Radiopharmaceutical DW-166HC for Anticancer drug

  • Man, Ryu-Jei
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1999년도 춘계학술대회
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    • pp.53-61
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    • 1999
  • Radiation therapy has been used for the cancer treatment and radiation synovectomy$\^$1-3)/. There are two kinds of radiation therapy; the external radiation therapy and the internal radiation therapy. Hitherto, the external radiation therapy has been widely used, but for the lack of its selectivity it requires strong radiation dose and causes the irritation and damage of the normal tissue or organ. Therefore many researchers give their interests to the internal radiation therapy in which the radioactive materials are injected directly into the target organ or tissue. Many ${\beta}$-emitting radionuclides have been studied for the application of the internal radiation theraily. Among them, Holmium-166 has the many beneficial physical characteristics for the internal radiation therapy such as appropriate half life (26.8hr), high ${\beta}$ energy (max. 1.85 MeV(51%), 1.77 MeV (48%), mean 0.67MeV), and low ${\gamma}$ energy (0.081MeV) easily detected by ${\gamma}$-camera. In the internal radiation therapy, the administered radioactive materials should be retained in the target long enough to increase the therapeutic effects and avoid the damage in the normal tissue or organ. For this purpose, radionuclides are used as complex form with carriers. Carriers should have a high affinity with radionuclides in vivo and in vitro, so the complex can be evenly distributed in the lesion but can not be leaked out from the lesion.

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