• 제목/요약/키워드: Re-direction

검색결과 463건 처리시간 0.029초

반경비 및 각속도의 변화에 따른 Taylor 유동에 관한 연구 (A STUDY ON TAYLOR FLOW ACCORDING TO RADIUS RATION AND ANGULAR VELOCITY)

  • 배강열;김형범;정희택
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 추계 학술대회논문집
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    • pp.127-133
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    • 2007
  • This paper represents the numerical study on Taylor flow according to the radius ratio and the angular velocity for flow between tow cylinder. The numerical model is consisted of two cylinder which inner cylinder is rotating and outer cylinder is fix, and the axial direction is used the cyclic condition because of the length for axial direction is assumed infinite. The diameter of inner cylinder is assumed 86.8 mm, the numerical parameters are angular velocity and radius ratio. The numerical method is compared with the experimental results by Wereley, and the results are very good agreement. The critical Taylor number is calculated by theoretical and numerical analysis, and the results is showed the difference about ${\pm}10\;%$. As $Re/Re_c$ is increased, Taylor vortex is changed to wavy vortex, and then the wave number for azimuthal direction is increased. Azimuthal wave according to the radius ratio is showed high amplitude and low frequence in case of small radius ratio, and is showed low amplitude and high frequence in case of large radius ratio.

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4차 산업혁명 시대를 대비한 교육과정재구성 담론의 재구성 (Reconstruction of Discourse on Curriculum Reconstruction)

  • 김대영;우옥희
    • 한국융합학회논문지
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    • 제9권6호
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    • pp.9-16
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    • 2018
  • 본 연구는 최근 교육과정 분야에서 강조되고 있는 교사의 교육과정 재구성 담론의 한계를 지적하고 대안적 담론을 제시하는데 그 목적이 있다. 먼저 선행연구 분석을 통해 기존 교육과정 재구성 담론이 교사의 전문성 신장을 통한 교육내용 선정 및 조직이라는 큰 틀에서 진행되고 있음을 밝히고 이러한 논의가 교육내용 선정의 방향을 결정하는데 한계가 있다는 점을 지적하고 있다. 이에 대한 대안으로 본 논문은 학습자 흥미를 교육과정 재구성 담론에 포함시킴으로써 그 방향성을 설정하는데 도움을 주고 있다. 보다 구체적으로 Dewey의 성장, 습관, 흥미의 개념이 어떻게 교육과정 재구성 담론과 연계될 수 있는지를 제시함으로써 향후 교육과정 재구성 논의를 풍부하게 할 수 있도록 하고 있으며, 실제 학교 수업에서 교사가 학습자의 흥미를 바탕으로 교육내용을 어떻게 선정하고 조직해야 할지를 제안하고 있다.

PIV measurements of near wake behind a sinusoidal cylinder

  • Zhang W.;Daichin Daichin;Lee S. J.
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2003년도 추계학술대회 논문집
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    • pp.59-62
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    • 2003
  • The near wake behind a sinusoidal cylinder at Re=5200 has been investigated using DPIV system. The velocity fields, streamlines and vorticity contours of the mean flow were compared at the nodal, saddle and middle planes with those of a right circular cylinder. For the sinusoidal cylinder, the vortex core moves downstream and the vortex formation region is expanded in streamwise direction while suppressed in transverse direction at the nodal plane. At the saddle and the middle plane the vortex spread in both streamwise and transverse directions, forming the maximum vortex region at the saddle plane.

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국제물품매매에서 물품검사시기에 관한 고찰 (A Study on the Buyer's Timely Inspection of the Goods in International Sale of Goods)

  • 하강헌
    • 무역상무연구
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    • 제74권
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    • pp.1-23
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    • 2017
  • The buyer must examine the goods, or cause them to be examined, within as short a period as is practicable in the circumstances. Article 38 lays down a fundamental principle that requires the buyer to examine quickly the goods delivered by the seller. Article 38 (1) provides that the examination be made within as short a period as practicable in the circumstances. The goods have to be examined within as short a period as is practicable in the circumstances. The rule is based on the fundamental idea of reasonableness, meaning that the buyer must examine the goods as soon as reasonably possible. It may be said that the buyer should act reasonably fast. Article 38 (2), (3) concerns sales involving carriage of the goods, where the seller's obligation to deliver consists in handing the goods over to the first carrier for transmission to the buyer. In this case the buyer is generally able to examine the goods only after they have come to destination. Article 38 (3) takes into account the case where the buyer redirects the goods in transit or re-dispatches them to another destination. Redirection in transit occurs when the destination is changed before the goods are received by the buyer. The buyer could re-dispatch the goods without having them unloaded, or re-dispatch them through another carrier.

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정육면체 주위 층류 유동에 근처 벽면이 미치는 영향 (WALL EFFECTS ON LAMINAR FLOW OVER A CUBE)

  • 김동주
    • 한국전산유체공학회지
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    • 제16권1호
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    • pp.83-89
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    • 2011
  • Laminar flow over a cube near a plane wall is numerically investigated in order to understand the effects of the cube-wall gap on the flow characteristics as well as the drag and lift coefficients. The main focus is placed on the three-dimensional vortical structures and its relation to the lift force applied on the cube. Numerical simulations are performed for the Reynolds numbers between 100 and 300, covering several different flow regimes. Without a wall nearby, the flow at Re=100 is planar symmetric with no vortical structure in the wake. However, when the wall is located close to the cube, a pair of streamwise vortices is induced behind the cube. At Re=250, the wall strengthens the existing streamwise vortices and elongates them in the streamwise direction. As a result, the lift coefficients at Re=100 and 250 increase as the cube-wall gap decreases. On the other hand, without a wall, vortex shedding takes place at Re=300 in the form of a hairpin vortex whose strength changes in time. The head of hairpin vortex or loop vortex, which is closely related to the lift force, seems to disappear due to the nearby wall. Therefore, unlike at Re=100 and 250, the lift coefficient tends to decrease more or less as the cube approaches the wall.

Re-enterant 공동 공진기의 주파수 가변 특성에 관한 실험적 고찰 (An Experimental Study on the Tuning Characteristics of a Re-enterant cavity resonator)

  • 김진구;홍의석
    • 한국통신학회논문지
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    • 제12권2호
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    • pp.133-138
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    • 1987
  • 본 논문에서는 Re-enterant 공동 공진기의 내부 도체봉 길이 변화에 따른 공진 주파수의 가변특성을 실험정그로 고찰하였다. 실험시 제작된 공진기는 동축 케이블과 원형 도파관을 경합한 형태로서 동축 케이블의 내부 도체봉의 길이를 축방향으로 면화시킬 수 있도록 하여, 내부 도체봉의 임의의 길이에 대한 Tmonq 모드의 공진 주파수를 측정하였다. 경과의 타당성을 입증하기 위해서 실험 경과와 여러 사람들의 이론치를 비교하였다. 본 실험의 결과는 파장계, 공진기?l 증폭기의 공진 회로의 설계및 제작에 활용할 수 있으며 마이크로 웨이브 집적회로(MIC, Microwave Integrated Circuits)나 여과기에 사용되는 유전체 공진기의 공진 주파수를 가변시키는데도 사용할 수 있다.

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하프 PC판과 후타설콘크리트 접합면의 면내전단강도에 관한 실험적 연구 (An Experimental Study on In-Plane Shear Strength of the Interface between Half PC Plate and Cast-in-Place Concrete Plate)

  • 신동원;고만영;이동우;김용부
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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    • pp.513-518
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    • 1998
  • In Half Precast Concrete Method, such as composite slab and composite wall, Interface between half PC plate and cast-in-place concrete is occurred. And this interface endure lastly in-plane shear which is occurred by external force. Therefore, test was executed to study in-plane shear strength of interface between half PC plate and cast-in-place concrete. In this test, Experimental parameters are finishing condition of the interface, cohesion of concrete, existence and nonexistence of re-bar truss, and angle and direction of lattice of re-bar truss. Comparing and analyzing experimental results, conclusions are obtained as follows. (1) In-plane shear strength of wide interface in composite plate is more affected by the roughness of interface than re-bar truss. And cohesion of concrete contribute to increasing in-plane shear strength. Therefore it seems that the interface should be roughen and kept clean to improve in-plane shear strength. (2) It seems that shear friction equation in ACI code can be sagely available for design of in-plane shear of composite plate.

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농촌마을 조성모델에 기초한 환경친화적 주거단지 입지 적합성 분석 (The Suitability Analysis of Environmentally Friendly Housing Site Based on the Rural Villages Model)

  • 송병화;양병이
    • KIEAE Journal
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    • 제4권2호
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    • pp.3-10
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    • 2004
  • The purpose of this study is to suggest the guidelines for suitability analysis of the environmentally friendly rural village housing site. And then this study is based on the rural village model for the rural village (re)development. The suitability analysis of environmentally friendly rural village housing site is conducted on Suryon dong, Wonju, Gangwon-do. The method of analysis is to secure validaty and reliability of the exact analysis of a geographic data for a decision-making statistical analysis. The results of this study is useful to prove it conclusively site-suitability to establish a principles and to change direction for the environmentally friendly rural village and rural housing (re)development.

Preparation of TZM Alloys Having Elongated Coarse-grain Structure with High Aspect Ratio and their Mechanical Properties

  • Toyosima, Gouhei;Nagae, Masahiro;Yoshio, Tetsuo;Takada, Jun;Hiraoka, Yutaka;Takida, Tomohiro
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1163-1164
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    • 2006
  • TZM alloy having elongated coarse-grain structure was developed by three-step internal nitriding treatment at 1423 to 1873 K in $N_2$ and subsequent recrystallization treatment at 2173 K in vacuum. Some specimens were subjected to re-nitriding treatment at 1873 K for 16 h. After the recrystallization treatment, aspect ratio (L/W) of grains for rolling direction was about 50 at the maximum. Yield stress obtained at 1773 K after re-nitriding treatment was about 6 times as large as that of recrystallized specimen. Re-nitriding was very effective in the improvement in strength of TZM alloy having elongated coarse-grain structure.

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참여정부 대통령기록 연구 기록 재조직을 중심으로 (A Study on the Participatory Government's Presidential Archives : Focusing on Re-organization of Records and Archives)

  • 곽건홍
    • 기록학연구
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    • 제61호
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    • pp.5-29
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    • 2019
  • 참여정부 대통령기록은 기록 생산 방식 혁신의 결과로 남겨졌다. 그 기록은 의사결정 전 과정을 증거하고 있으며, 투명성과 설명책임성을 제고하는 수단으로 작용하였다. 본고는 기록의 존재형태를 분석하여 기록 재조직의 필요성을 주장하였다. 기록 재조직 방향으로 기록 분류체계 재설계, 기록의 논리적 재편철, 기록 건 상세정보의 기술 등을 제안하였다. 대통령기록의 이용을 활성화하기 위해서는 대통령기록관이 조속히 이러한 작업을 진행해야 한다.