• 제목/요약/키워드: 수막

검색결과 314건 처리시간 0.022초

부인두강 종양으로 발현한 두개외 수막종 (Extracranial Meningioma as a Parapharyngeal Space Tumor)

  • 이대웅;최정욱;오승은;이준규;임상철
    • 대한두경부종양학회지
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    • 제26권2호
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    • pp.259-261
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    • 2010
  • The meningiomas are slowly growing tumors arising from meningoepithelial cells and they generally occur in the intracranial space. Tumor extension to the extracranial structures occurred in about 20 percent of intracranial meningiomas. Meningiomas extending to the cervical area are uncommom. Beacuse these patients complain of localized symptoms, sometimes those tumors have been operated as cervical tumors. In this report, we incidentally found a meningioma in the left parapharyngeal space in a 63-year-old female, who was confirmed by histopathologic diagnosis to have meningioma. We report herewith this case with the review of literatures.

수막을 가지는 선형 젖음성 패턴 표면에서의 액적 거동 특성 (The Behavioral Characteristics of a Droplet on the Line Patterned Surface Including Water Film)

  • 이창우;박진영;조한동;황운봉
    • 한국정밀공학회지
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    • 제30권12호
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    • pp.1335-1340
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    • 2013
  • Herein the water film was introduced to the hydrophilic area on the line patterned surface to solve the contradiction caused by surface roughness (high different wettability has advantage to control the droplet but high roughness for that high wettability difference causes obstruction of droplet moving). Thus the droplet on the water film could not be hindered to line direction but restricted to orthogonal direction, effectively. In addition, droplet behaviors according to droplet volume and line thickness were studied. Droplet fell off the line with narrowing the interface between the droplet and the water film on the line. When the droplet fell off the line, the plate angle was designated as a critical plate angle and it used as an indicator of surface capability to control the droplet. As a result critical plate angle increases as droplet volume decreases and line thickness increases.

채널이 수막으로 완전히 덮여 있는 증발식 냉각기에서의 열 및 물질전달 해석 (Analysis of Heat and Mass Transfer in an Evaporative Cooler with Fully Wetted Channel)

  • 송찬호;이대영;노승탁
    • 대한기계학회논문집B
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    • 제25권12호
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    • pp.1766-1775
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    • 2001
  • A theoretical analysis on the heat and mass transfer in an evaporative cooler is presented in this work. The evaporative cooler is modeled as a channel filled with porous media the interstitial surface of which is covered by thin water film. Assuming that the Lewis number is unity and the water vapor saturation curve is linear, exact solutions to the energy and vapor concentration equations are obtained. Based on the exact solutions, the characteristics of the heat and mass transfer in the evaporative cooler are investigated. The comparison of the cooling performance between the evaporative cooler and the usual sensible heat exchanger is also carried out. Obviously, the evaporative heat exchanger shows better cooling performance than the sensible heat exchanger. This is due to the latent heat of water vaporization, which results in apparent increases both in the interstitial heat transfer coefficient and the specific heat of the air stream in the evaporative cooler.

흑색 코발트 태양 선택흡수막의 열퇴화 (Thermal Degradation of Black Cobalt Solar Selective Coatings)

  • 이길동
    • 한국태양에너지학회 논문집
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    • 제35권4호
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    • pp.9-15
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    • 2015
  • Black cobalt solar selective coatings were prepared by using an electroplating method. The changes in the optical properties of the black cobalt selective coating due to thermal degradation were analyzed by using the Auger electron spectroscopy (AES) and spectrophotometer. The black cobalt selective coating was prepared on a copper substrate by using a synthesized electrolyte with $CoCl_2$ and KSCN at a current density of ${\sim}0.5A/dm^2$ for 45s ~ 60s. Its optical properties were a solar absorptance (${\alpha}$) of the order of 0.80 ~ 0.84 and a thermal emittance (${\epsilon}$) of 0.01. From the AES depth profile analysis of heated sample, thermal degradation of the black cobalt selective coating heated for 33 hours at temperature of $350^{\circ}C$ occurred primarily due to interdiffusion at interface of cobalt and copper substrate. This results were predictable that the ${\alpha}$ decreases due to the thermal oxidation and diffusion.

고온용 태양 선택흡수막의 제작 (Deposition of Solar Selective Coatings for High Temperature Applications)

  • 이길동
    • 한국태양에너지학회 논문집
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    • 제28권1호
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    • pp.33-42
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    • 2008
  • Zr-O ($Zr-ZrO_2$) cermets solar selective coatings with a double cermets layer film structure were prepared using a DC (direct current) magnetron sputtering method. The typical film structure from surface to bottom substrate were an $Al_2O_3$ anti-reflection layer on a double Zr-O cermets layer on an Al metal infrared reflection layer. Optical properties of optimized Zr-O cermets solar selective coating had an absorptance of ${\alpha}\;=\;0.95$ and thermal omittance of ${\epsilon}\;=\;0.10\;(100^{\circ}C)$. The absorbing layer of Zr-O cermets coatings on glass and silicon substrate was identified as being amorphous by using XRD. AFM showed that ZF-O cermets layers were very smooth and their surface roughness were approximately $0.1{\sim}0.2 nm$. The chemical analysis of the cermets coatings were determined by using XPS. Chemical shift of photoelectron binding energy was occurred due to the change of Zr-O cermets coating structure deposited with increase in oxygen flow rate. The result of thermal stability test showed that the Zr-O cermets solar selective coating was stable for use at temperature below $350^{\circ}C$.

범발성 두개내 결핵종 완치 1례 (A Case of Complete Treatment of Multiple Intracranial Tuberculoma)

  • 라은영;이창우
    • Pediatric Infection and Vaccine
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    • 제9권1호
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    • pp.117-121
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    • 2002
  • 어린 영유아에서 결핵성 육아종 및 결핵성 수막염, 속립성 결핵 등의 중증 결핵은 치료 시작시 임상상태와 밀접한 연관이 있으며 경과가 진행될수록 예후가 좋지 못하다. 본 증례에서는 결핵성 육아종과 함께 결핵성 수막염 및 속립성 결핵이 동반된 영아에서 12개월 동안 항결핵 요법을 시행한 후 특별한 임상적, 이학적, 신경학적 이상 소견 없는 완치를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

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흑색 코발트 태양 선택흡수막의 광학적특성과 구조 (Optical Properties and Structure of Black Cobalt Solar Selective Coatings)

  • 이길동
    • 한국태양에너지학회 논문집
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    • 제31권4호
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    • pp.48-56
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    • 2011
  • Black cobalt solar selective coatings were prepared by thermal oxidation of electroplated cobalt metal on copper and nickel substrates. The optical properties and structure of the black cobalt selective coating for solar energy utilizations were characterized by glow discharge spectrometry (GDS), ultraviolet-visible-near infrared (UV-VIS-NIR) spectrometer, atom force microscopy(AFM) and X-ray photoelectron spectroscopy(XPS). The optical properties of optimum black cobalt selective coating prepared on copper substrate were a solar absorptance of 0.82 and a thermal emittance of 0.01. From the GDS depth profile analysis of these coatings, the concentration of cobalt particles near the interface was higher than at the surface, but oxygen concentration at the surface was higher than at the interface. These results suggest that the selective absorption was dominated by this chemical composition variation in the coating. The surface of this film exhibited morphology with root-mean-square(rms) roughness of about 144.3nm. XPS measurements data showed that several phases of Co coexist($Co_3O_4$,CoO) in the film.

수막뇌염을 모방한 드문 뇌 자기공명영상 소견을 보인 하시모토 뇌병증: 증례 보고 및 문헌고찰 (Hashimoto's Encephalopathy with Unusual MRI Findings Mimicking Meningoencephalitis: A Case Report and Literature Review)

  • 서희붐;김현석;김학진
    • 대한영상의학회지
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    • 제81권2호
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    • pp.453-458
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    • 2020
  • 하시모토 뇌병증은 다른 대뇌 질환의 증거가 없이 항갑상선 항체의 높은 혈청 농도를 특징으로 하는 드문 자가 면역 질환이다. 하시모토 뇌병증의 자기공명영상 소견은 비특이적이고, 현재까지 미만성 또는 국소 백질 변화가 보고 된 바 있다. 저자는 증가된 항갑상선 항체와 동반하여 수막뇌염과 유사한 영상 소견을 보인 79세 여성의 하시모토 뇌병증을 경험하여 이에 대해 보고하고자 한다. 환자의 일련의 자기공명영상에서 치료 전 관찰되던 여러 T2-고강도 병변과 미만성의 뇌수막 조영증강은 스테로이드 요법 후 소실되었다.

순환식 지하수 수막시스템 그린하우스 난방을 위한 스탠딩컬럼웰 열교환율 산정 (Estimation of Heat Exchange Rate of Standing Column Well for Sustainable Groundwater Curtain for Greenhouse Heating)

  • 심병완;백승균;정성훈
    • 한국지열·수열에너지학회논문집
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    • 제20권2호
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    • pp.11-23
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    • 2024
  • In order to design a standing column well (SCW) for a sustainable groundwater curtain system for greenhouse heating, we conducted parameter sensitivity tests. These tests simulated the outlet temperature changes of the SCW in a groundwater recirculating greenhouse cultivation system. Our modeling considered ground thermal conductivity and hydrogeological conditions. Specifically, we examined several factors, including SCW length, enhanced thermal conductivity of the ground, and groundwater circulation rate. The simulation results indicated that there was not a significant difference in the heat exchange rate based on the characteristics of enhanced thermal conductivity. However, we anticipate a substantial difference in the case of varying SCW lengths. Therefore, we conclude that the simulation results are primarily influenced by conductive heat exchange values, as the circulating water remains at a constant groundwater level.