• 제목/요약/키워드: Field wall

검색결과 1,608건 처리시간 0.033초

변압기 철심용 Fe-B-Si비정질 합금의 철손 특성 (Core Losses of Amorphous Fe-B-Si Alloy for Transformer Core)

  • 김기욱;송재성;홍진완;강원구
    • 대한전기학회논문지
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    • 제40권1호
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    • pp.67-72
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    • 1991
  • For improving the magnetic properties of the amorphous Fe-B-Si alloy, we annealed the sample in a magnetic field oriented in the plane of the ribbon longitudinal to its long axis. By field annealing, coercive force and total core loss are reduced from 0.04 Oe to 0.02 Oe, and from 0.25 watt/kg to 0.15 watt/kg respectively in comparsion with non-field annealed specimen. These reductions were caused by the formation of 180 dcmain wall parallel to the annealing field due to the induced anisotropy.

침투성 코팅 처리된 벽면 주위의 벽 압력 특성 (Characteristics of Wall Pressure over Wall with Permeable Coating)

  • 송우석;신승열;이승배
    • 대한기계학회논문집B
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    • 제36권11호
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    • pp.1055-1063
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    • 2012
  • 16채널 어레이 마이크로폰을 이용하여 난류 유동장 내 벽면 압력섭동에 대한 측정을 수행하였다. 본 실험에 사용된 코팅재질은 약 50 ppi (pores per inch)의 다공성 구조로 이루어진 우레탄 물질로 이루어져 있다. 코팅의 주된 목적은 난류 유동장 내 최소한의 공간을 유지하면서 대류속도로 진행하는 난류 와들을 필터링하는 역할을 하는 것이다. 평판 위 경계층의 측정은 열선 유속계를 이용하였으며 표면 마찰계수 값을 얻기위해 CPM법을 사용하였다. 벽압력 스펙트럼과 파수-주파수 스펙트럼 측정은 코팅에 의해 얼마나 에너지가 저감되는 지를 비교하기 위해 사용되었다. 벽면 코팅은 대류하는 무차원 벽면섭동압력에너지를 저감시켰지만, 컴플라이언트 코팅된 벽면 거칠기로 인해 일반 강체 평판에 비해 상대적으로 발달된 경계층을 형성하였으며 벽면 평균전단응력과 저주파수 압력스펙트럼 레벨도 함께 증가하였다.

점성토 시료추출관이 시료교란에 미치는 영향 (Effect of Thin Wall Tube on Clay Soil Disturbance during Sampling)

  • 임성훈
    • 한국농공학회논문집
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    • 제51권5호
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    • pp.51-58
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    • 2009
  • The total recovery ratio test on undisturbed clay soil sampling in the field and the finite element method analysis on modified static state of penetration process were conducted for the purpose of deciding the most important factor among the shape factors of thin wall tube. The adhesion between tube wall and soil did not decrease although internal clearance ratio of tube increased within the little change of tube area ratio. The most part of disturbance occurred in the tip of sampling tube during the penetration. The longitudinal displacement was larger than the lateral displacement because soil was confined laterally after being entered into tube, and also the longitudinal displacement was larger in the upper part of the sample tube than in the lower part.

보강토 옹벽의 지진시 거동 (Behavior of Soil-Reinforced Segmental Retaining Walls Subjected to Earthquake Loading)

  • 유충식
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.379-386
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    • 2000
  • This paper presents the results of finite element analysis on the seismic response of a soil-reinforced segmental retaining wall subjected to a prescribed earthquake record. The results of finite element analysis indicate that the maximum wall displacement occurs at the top, exhibiting a cantilever type of wall movement. Also revealed is that the increase in reinforcement force is more pronounced in the upper part of the reinforced zone, resulting in a more or less uniform distribution. None of the design guidelines appears to be able to correctly predict the dynamic force increase when compared with the results of finite element analysis. The calculation model adopted by the NCMA guideline, however, appears to compare better with the results of finite element analysis as well as field survey than the FHWA guideline. Based on the findings from this study, a number of implications to the current design methods are discussed.

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결핵성 흉벽농양 (Tuberculous chest wall abscess)

  • 조규석;우세영
    • Journal of Chest Surgery
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    • 제17권1호
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    • pp.140-143
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    • 1984
  • We have experienced 30 patients of tuberculous chest wall abscess which was surgically treated at Kyung Hee University hospital during 6 years from Jan, 1978 to Dec, 1983. We analyze 30 cases of clinical findings and surgically treated, and 20 cases of chest X-rays are available. The results of this sturdy are as follows: 1.Sex ratio ; Male: Female = 1:1.72. 2.Chief complaints are fluctuated mass with or without tenderness or pain and pus from wound. 3.Out of 20 cases of chest x-rays revealed 8 cases of osteolytic lesion, 11 cases of soft tissue swelling, 5 cases of pleural changes and 4 cases of negative findings. 4.We resected partially 43 ribs of 30 patients [average: 1.43 resected] in tuberculous chest wall abscess. 5.Operative methods of tuberculous chest wall abscess were partial resection of destructed or denuded periosteum of ribs and curettage of its surrounding tissues in operative field.

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Hot Wall Epitaxy (HWE)에 의한 성장된 $ZnIn_2S_4$ 단결정 박막의 광전류 특성 (Opto-electric Properties of $ZnIn_2S_4$ single crystal thin film Grown by Hot Wall Epitaxy method)

  • 홍광준;이상열
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.71-72
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    • 2006
  • The stochiometric mixture of evaporating materials for the $ZnIn_2S_4$ single crystal thin film was prepared from horizontal furnace. To obtain the $ZnIn_2S_4$ single crystal thin film. $ZnIn_2S_4$ mixed crystal was deposited on throughly etched semi-insulating GaAs(100). In the Hot Wall Epitaxy(HWE) system. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the $ZnIn_2S_4$ single crystal thin film, we have found that the values of spin orbit splitting ${\Delta}So$ and the crystal field splitting ${\Delta}Cr$ were 0.0148 eV and 0.1678 eV at $10_{\circ}K$, respectively.

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Activation Volumes of Wall-Motion and Nucleation Processes in Co/Pd Multilayers

  • Choe, Sug-Bong;Shin, Sung-Chul
    • Journal of Magnetics
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    • 제5권2호
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    • pp.35-39
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    • 2000
  • The correlation between the activation volumes of wall-motion and nucleation processes in Co/Pd multilayers has been investigated. Each activation volume was estimated from the field dependence of the wall-motion speed and the nucleation rate, respectively, based on time-resolved domain patterns grabbed by a MOKE microscope system. Both the activation volumes are changed in the same manner around $0.2\sim1.1\times10^{-17}cm^3$ with changes in the multilayered structure. Interestingly, the correlation between the activation volumes is sensitive to the multilayered structure; the wall-motion activation volume is smaller than the nucleation activation volume for a sample having a smaller number of repeats and a thinner Co-layer thickness, and vice versa. The correlation is closely related with the contrasting reversal modes; the process having the smaller activation volume dominates.

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건식벽체에 폴리싱타일을 적용하기 위한 유기.무기질 혼합계 타일접착제 종류에 따른 부착안정성 평가 연구 (A Study on the Estimation of Adhesive Stability According to Organic Inorganic Mixed Tile Bond Type for Application of Polishing Tile to Dry Wall System)

  • 유재강;박성규;배기선;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2001년도 학술논문발표회
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    • pp.8-13
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    • 2001
  • In recently, polishing tile(porcelain homogeneous polished tile) was used in the construction field as a finishing material. But, there happened some problems such as tile exfoliation by construction condition in early ages. Also, in the dry wall system which used to lightweight wall, for use of polishing tile on dry wall, the examination of adhesive stability of polishing tile is needed. In this Paper, adhesive strength of Polishing tile was investigated by tile bond types on gypsum board and non asbestos board coated by tar-urethane and polymer modified cementitious waterproofing membrane(Series I). Then, the effect of heat stress and vibration was estimated on gypsum and non asbestos board(Series II).

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창덕궁 담에 접한 자생주거지에 관한 연구 - 원서동 무허가 94번지의 실측 및 개선 안 기초연구 - (A Field Survey of Idiosyncratic Dwelling Space attached to Chang-Duk Palace's West Fence)

  • 윤숙희;정진원
    • 한국주거학회논문집
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    • 제14권1호
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    • pp.29-40
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    • 2003
  • The purpose of this research is to document and analyse spatial transformation of an unauthorized dwelling units on a peculiar site of Seoul. It's physically attached to the behind part of the west boundary wall of Chang-Duk Palace. These dwelling units took not only the site, the narrow street which had been a stream, but also the two parallel walls of others for their home. The two walls, one from the palace wall and the other from the wall of a house which distanced itself from the palace wall about 3.5 m for the reason of the Cultural Properties Protection Law, have been held as the main structural members in forming the shelter. With examining the realm of time which provide the base of the spatial realm, this research shows how the multiple linkages tangled in an illegal shack did gain and actualize an architectural language of idiosyncrasy with spontaneous order inherent in inhabitants.

An Overview of Liquid Spray Modeling Formed by High-Shear Nozzle/Swirler Assembly

  • Koo, Ja-Ye
    • Journal of Mechanical Science and Technology
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    • 제17권5호
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    • pp.726-739
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    • 2003
  • A multi-dimensioanl model is being increasingly used to predict the thermo-flow field in the gas turbine combustor. This article addresses an integrated survey of modeling of the liquid spray formation and fuel distribution in gas turbine with high-shear nozzle/swirler assembly. The processes of concern include breakup of a liquid jet injected through a hole type orifice into air stream, spray-wall interaction and spray-film interaction, breakup of liquid sheet into ligaments and droplet,5, and secondary droplet breakup. Atomization of liquid through hole nozzle is described using a liquid blobs model and hybrid model of Kelvin-Helmholtz wave and Rayleigh-Taylor wave. The high-speed viscous liquid sheet atomization on the pre-filmer is modeled by a linear stability analysis. Spray-wall interaction model and liquid film model over the wall surface are also considered.