• 제목/요약/키워드: Separated Body

검색결과 428건 처리시간 0.021초

Mixing Enhancement/Suppression of Separated-and-Reattaching Flow by an Upstream Small Object

  • IINVMA, Yusuke;FUNAKI, Jiro;HIRATA, Katsuya
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.106-110
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    • 2004
  • Generally, flow around a bluff body such as a circular cylinder is complicated compared with that around a streamlined body because of the existence of separated shear layers. Long bluff body such as a flat blunt plate is more complicated than short bluff body, because of separated-and-reattaching flow on the after bodies.(omitted)

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항공기 탑재체의 분리 후 공력 특성 변화 효과 (Changing Effect in Aerodynamic Characteristics of a Captive Body Separated from Aircraft)

  • 조환기;이상현;강치행
    • 한국군사과학기술학회지
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    • 제14권3호
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    • pp.397-404
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    • 2011
  • The aerodynamic characteristics of a separated captive body in flow field around aircraft are studied to observe aerodynamic stability for safe separation from aircraft. Since the captive body separated from aircraft is initially exposed to unsteady flow pattern, the change of aerodynamic forces and moments should be measured to analyze how the flow pattern affects on the captive body at the vicinity of aircraft. Aerodynamic forces and moments of the separated captive body are measured at selected positions along predictable dropping trajectories. The measuring trajectories, generated by the free drop test of the dropping model in the wind tunnel, are consisted of 9 possible lines by free dropped trajectories. Experimental results show that the aerodynamic forces and moments are significantly varied with the distance between the captive body and aircraft. In conclusion, the change of aerodynamic characteristics within flow field around aircraft should be considered to simulate trajectories of the separated captive body from aircraft.

국산 공정석함유 혈암의 요업적 개발에 관한 연구 (Studies on the Utilization of Domestic Shale contained Chiastolite for Ceramics)

  • 정영기;오재현;이희수
    • 한국세라믹학회지
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    • 제12권3호
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    • pp.3-7
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    • 1975
  • The usefulness of the domestic shale contained chiastolite as additive were investigated. Crude mixed minerals were separated into shale and chiastolite. Refractory body added simple component or multiple components as additives was obtained when firing at 125$0^{\circ}C$ for each body. Compressive strength, refractories, apparent sp. gr., water absorption, corrosion test by slag, hot linear expansion were measured and X-ray diffraction analysis was observed. As the result of study, refractory body contained separated minerals as additives showed slightly increasing in refractoriness, lowering in sintering effect, the excellent effect for corrosion resistance by acidic slag. With more containing separated minerals, hot linear expansion for the body can be decreased.

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Motion Analysis of Two Floating Platforms with Mooring and Hawser Lines in Tandem Moored Operation by Combined Matrix Method and Separated Matrix Method

  • KOO BON-JUN;KIM MOO-HYUN
    • 한국해양공학회지
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    • 제19권5호
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    • pp.1-15
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    • 2005
  • The motion behaviors including hydrodynamic interaction and mechanical coupling effects on multiple-body floating platforms are simulated by using a time domain hull/mooring/riser coupled dynamics analysis program. The objective of this study is to evaluate off-diagonal hydrodynamic interaction effects and mechanical coupling effects on tandem moored FPSO and shuttle taker motions. In the multiple-body floating platforms interaction, hydrodynamic coupling effects with waves and mechanical coupling effects through the connectors should be considered. Thus, in this study, the multiple-body platform motions are calculated by Combined Matrix Method (CMM) as well as Separated Matrix Method (SMM). The advantage of the combined matrix method is that it can include all the 6Nx6N full hydrodynamic and mechanical interaction effects among N bodies. Whereas, due to the larger matrix size, the calculation time of Combined Matrix Method (CMM) is longer than the Separated Matrix Method (SMM). On the other hand, Separated Matrix Method (SMM) cannot include the off-diagonal 6x6 hydrodynamic interaction coefficients although it can fully include mechanical interactions among N bodies. To evaluate hydrodynamic interaction and mechanical coupling effects, tandem moored FPSO and shuttle tanker is simulated by Combined Matrix Method (CMM) and Separated Matrix Method (SMM). The calculation results give a good agreement between Combined Matrix Method (CMM) and Separated Matrix Method (SMM). The results show that the Separated Matrix Method (SMM) is more efficient for tandem moored FPSO and shuttle tanker. In the numerical calculation, the hydrodynamic coefficients are calculated from a 3D diffraction/radiation panel program WAMIT, and wind and current forces are generated by using the respective coefficients given in the OCIMF data sheet.

Albumin density gradient 방법에 의한 고활력 우정자 분리시의 정자두부크기의 비교관찰 (Effect of Isolation by Albumin Density Gradients on Head's Size of Bovine Sperm)

  • 김명철;조충호;정순오
    • Clinical and Experimental Reproductive Medicine
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    • 제11권2호
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    • pp.69-76
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    • 1984
  • In order to obtain high proportion of Y sperm the semen was laid over 6%,10% and 20% bovine serum albumin. Separated sperm were stained with quinacrine mustard in order to see F - body which could be seen in human Y sperm. But we could'nt find F-body in the bull sperm. So sperm were compared with size of sperm head. As a result of observation separated sperm was small in size of length and width of sperm head as compared with control sperm. So it was found that the proportion of Y sperm showed a marked increase in separated layer. Then the higher albumin density was, the higher the proportion of Y sperm which had smaller head and faster motility was. But the higher albumin density was, the lower the recovery rate of sperm was. So it was hard to separate Y sperm in oligospermia.

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Generation and Suppression of Non-uniform Flow in Scramjet Engines

  • Ben, Hidenori;Watanabe, Toshinori
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.69-74
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    • 2004
  • In scramjet engines with sidewall compression inlet, it is well known that a non-uniform flow appears since a separated region is generated near the flow centerline on the body side. The separated region is caused by shock-boundary layer interaction and likely to cause un-start phenomena since the flow in the separated region is subsonic and acts as a communication path between the isolator and the combustor. In the present study, the non-uniform flow characteristics in the scramjet inlet-isolator region are numerically studied in detail. Effect of flow suction from body sidewall surface on the non-uniform flow field numerically examined to clarify the flow mechanism to suppress the un-start transition.

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개구리 망막체와 수정체의 Amino 산 성분에 관한 연구 (Studies on the Composition of Amino Acid in Retina and Lens Body of the Frogs)

  • 강성호
    • 한국동물학회지
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    • 제2권2호
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    • pp.10-14
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    • 1959
  • The retinae and the lens bodies of the frogs were hydrolyzed with 20% hydrochloric acid, and their amino acids were separated by paper chromatography. As a result of it the following were confirmed : (1) The retinae and the lens bodies were the same incomposition, and aspartic acid, glutamic acid, serine ,tyrosine, glycine, lysine arginine, threonine, alanine, histidine, proline, methionine, valine , phenylalanine, leucine, and two unknown substances were separated. (2) The free amino acids in the retinae were extracted with 80% ethyl alcohol and then separated by paper chromatography. Though their separation was not so definite , serine, gultaminc acid, and glycine were always separated regardless of the amount of the sample. When the amount of the smaple was enough , $\beta$-alanine , ${\gamma}$-amino butyric acid and methionine +valine were also separated. (2) The free amino acids in the retinae were extracted with 80% ethyl alcohol and then separated by paper chromatography. Though their separation was not so definite, serine, glutamic acid, and glycine were always separated regardless of the amount of the sample . When the amount of the sample was enough, $\beta$-alanine , ${\gamma}$-amino butyric acid and methionine + valine were also separated.

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인체 유래 생물학적 물질의 소유권 - 사체를 중심으로 - (Ownership of Human Biological Material - Concerning on Dead Body -)

  • 정규원
    • 의료법학
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    • 제18권1호
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    • pp.37-60
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    • 2017
  • 전통적인 법이론에 의하여 인간은 권리의 주체이기 때문에 인체로부터 유래한 생물학적 물질은 권리의 객체가 될 수 없다. 하지만 의학과 생명과학의 발전으로 인하여 인체로 부터 유래한 생물학적 물질은 다양한 용도로 사용되고 있으며 인체로부터 유래한 생물학적 물질의 객체성 여부와 소유권 인정 여부에 대한 논의는 지속적으로 제기되고 있다. 인체로부터 유래한 생물학적 물질을 법적으로 파악하는 이론은 전통적으로 자율성에 근거한 모델이었으며 현재도 그것이 가장 보편적으로 받아들여지고 있다. 하지만 자율성 모델에 의하여 인체로부터 유래한 생물학적 물질을 파악할 경우 인체로부터 유래한 생물학적 물질을 다루는 현실을 제대로 설명할 수 없을 뿐만 아니라 오히려 배분적 정의의 측면에서 볼 때 적절하지 못한 결론에 도달할 수도 있다는 의문이 제기되고 있다. 인체 유래 생물학적 물질을 소유권의 객체로 파악하려는 소유권 모델은 인간의 존엄과 가치에 반하는 이론 구성이라는 의혹을 받고 있다. 하지만 소유권은 단일한 권리가 아니며 다양한 권리들의 집합체이며 그 내용이 어떻게 구성될 것인가는 객체의 특성 등을 고려하여 판단하면 될 것으로 생각된다. 본 논문은 인체 유래 생물학적 물질의 소유권 전체 보다는 일단 사체로부터 유래한 물질의 소유권 인정 여부를 중점적으로 다루었다. 이를 통하여 인체 유래 생물학적 물질전반에 대한 법이론적 고찰이 현재의 과학적 사실에 적합한 형태로 이루어지기를 기대한다.

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저항감소를 위한 물체후방의 형상설계에 관한 LES 해석 (Large Eddy Simulations on the Configuration Design of Afterbodies for Drag Reduction)

  • 박종천;강대환;전호환
    • 한국해양공학회지
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    • 제17권5호
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    • pp.1-10
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    • 2003
  • When a body with slant angle behind its shoulder is moving at a high speed, the turbulent motion around the afterbody is generally associated with the flow separation, and determines the normal component of the drag. By changing the slant angle of the afterbody, the drag coefficients can be changed, drastically. Understanding and controlling the turbulent separated flows has significant importance for the design of optimal configuration of the moving bodies. In this paper, a new Large Eddy Simulation technique has been developed to investigate turbulent vortical motions around the afterbodies, using slant angle. By understanding the structure of the turbulent flow around the body, the new configuration of afterbodies is designed to reduce the drag of body, and the nonlinear effects, due to the interaction between the body configuration and the turbulent separated flows, are investigated by use of the developed LES technique.

저항감소를 위한 물체후방의 형상설계에 관한 LES 해석 (Large Eddy Simulations on the Configuration Design of Afterbodies for Drag Reduction)

  • 박종천;강대환;전호환
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 춘계학술대회 논문집
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    • pp.49-55
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    • 2003
  • When a body with slant angle after its shoulder is moving at high speed, the turbulent motion around the afterbody is generally associated with the flaw separation and determines the normal component of the drag. By changing the slant angle of afterbody, there exists a critical angle at which the drag coefficients change drastically. Understanding and control of the turbulent separated flows are of significant importance for the design of optimal configuration of the moving bodies. In the present paper, a new Large Eddy Simulation technique has been developed to investigate turbulent vortical motions around the afterbodies with slant angle. By basis of understanding the structure of turbulent flaw around the body, the new configuration of afterbodies are designed to reduce the drag of body and the nonlinear effects due to the interaction between the body configuration and the turbulent separated flows are investigated by use of the developed LES technique.

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