• 제목/요약/키워드: Strong Edge

검색결과 296건 처리시간 0.039초

PECVD에 의한 TiN 코팅의 마모특성 연구 (Wear Characteristics of TiN Coating by Plasma Enhanced CVD)

  • 송건;안효석
    • Tribology and Lubricants
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    • 제6권1호
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    • pp.116-125
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    • 1990
  • An experimental programme was established to determine the wear behaviour of TiN coatings of thickness 1 $\mu$m and 3 $\mu$m. by PECVD with the variation of applied load, sliding velocity and sliding distance. It was shown that oxidation of transferred metal as sliding speed increased formed oxide film so that it contributed in decreasing the wear rate. With the roller-on-disc tribometer employed, the wear rate of the roller specimen was decreased with the increase in sliding distance due to the reduction in effective contact pressure. Finally, the severe cracks concentrated at the trailing edge of contact surface were explained in terms of high tensile stress prevailing at the trailing edge of the contact and were identified as a dominant wear mechanism as well as the strong local welding between coating layer and the counter surface, leading to the debonding of the coating layer.

잠자리 모사 모형 주변의 유동가시화 실험 (Flow Visualization on the Bio-Mimic Model of Dragonfly)

  • 윤준용;엄상진;지영무;박준상
    • 한국가시화정보학회지
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    • 제8권2호
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    • pp.16-22
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    • 2010
  • A flow visualization has been conducted to investigate unsteady flight characteristics of a model of dragonfly. The mechanism of lift generation by flapping wings is analyzed using smoke-wire and high speed camera. The experimental results of flow visualization show a discernible sequential dynamics that three mechanisms and high incidence angle of the wings are responsible for the lift generation. The leading edge vortex by the rapid acceleration of leading edge of the wing during initial stage of stroke causes a strong lift enhancement. Delayed stall during the stroke, fast supination and pronation of the wing near the end of each stroke are also responsible for the lift generation.

자율 적응 최소-최대 유전 군집호와 퍼지 벌레 검색을 이용한 영상 영역화 (Image segmentation using adaptive MIN-MAX genetic clustering and fuzzy worm searching)

  • 하성욱;서석배;강대성
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.781-784
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    • 1998
  • An image segmentation approach based on the fuzzy worm searching and MIN-MAx clusterng algorithm is proposed in this paper. This algorithm deals with fuzzy worm value and min-max node at a gross scene level, which investigates the edge information including fuzzy worm action. But current segmentation methods based edge extraction methods generally need the mask information for the algebraic model, and take long run times at mask operation, wheras the proposed algorithm has single operation ccording to active searching of fuzzy worms. In addition, we also genetic min-max clustering using genetic algorithm to complete clustering and fuzyz searching on grey-histogram of image for the optimum solution, which can automatically determine the size of rnages and has both strong robust and speedy calculation. The simulation results showed that the proposed algorithm adaptively divided the quantized images in histogram region and performed single searching methods, significantly alleviating the increase of the computational load and the memory requirements.

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A No-Reference Adaptive Metric for Digital Image Quality Assessment

  • Lim, Jin-Young;Kang, Dong-Wook;Kim, Ki-Doo;Jung, Kyeong-Hoon
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.316-320
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    • 2009
  • In this paper, a reference-free perceptual quality metric is proposed for image assessment. It measures the amount of overall blockiness and blurring in the image. And edge-oriented artifacts, such as ringing, mosaic and staircase noise are also considered. In order to give a single quality score, the individual artifact scores are adaptively combined according to the difference between the edge-oriented artifacts and other artifacts. The quality score obtained by the proposed algorithm shows strong correlation with the MOS values by VQEG.

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이온주입식 자기버블 전산기 기억소자에서의 자기버블 전파실패에 관한 연구 (A Study On The Propagation Failure Modes of Ion Implanted Magnetic Bubble Computer Memory Devices)

  • 조순철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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    • pp.339-342
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    • 1988
  • Typical magnetic bubble propagation failure modes of ion implanted magnetic bubble computer memory devices were observed and their failure mechanisms were analize. The skidding failure mode is due to the pushing of a strong repulsive charged wall. If this pushing is stronger than the edge affinity of the bubble in the cusp, the bubble moves out of the cusp when it is supposed to stay there. The stripeout failure modes across the adjacent track or along the track can be explained by considering the relative strength of the charged wall and the edge affinity encountered by both ends of the stripe. The skipping of the first cusp of a track is believed to be due to the whipping motion of the charged wall. The bubble moves directly to the second cusp via the long charged wall pointing to the second cusp skipping the first cusp.

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에너지 비를 이용한 손실 블록 (Lost Block Recovery Using Energy Ratio)

  • 현승화;엄일규;김유신
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.329-330
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    • 2006
  • This paper presents a recovery technique for images with block-based corruption by transmission losses. Conventional methods that do not consider edge directions can cause blocked blurring artifacts. In this paper, we present a block recovery scheme using Haar wavelet features. The adaptive selection of neighboring blocks is performed based on the energy ratio f wavelet subbands. The lost blocks are recovered by linear interpolation in the spatial domain using selected block pairs. The proposed directional recovery method is effective for the strong edge because it exploits the varying neighboring blocks adaptively according to the edges and the directional information in the image. The proposed method outperforms the previous methods that used only a predefined set of neighboring blocks.

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An assessment of code designed, torsionally stiff, asymmetric steel buildings under strong earthquake excitations

  • Kyrkos, M.T.;Anagnostopoulos, S.A.
    • Earthquakes and Structures
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    • 제2권2호
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    • pp.109-126
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    • 2011
  • The inelastic earthquake response of non-symmetric, braced steel buildings, designed according to the EC3 (steel structures) and EC8 (earthquake resistant design) codes, is investigated using 1, 3 and 5-story models, subjected to a set of 10, two-component, semi-artificial motions, generated to match the design spectrum. It is found that in these buildings, the so-called "flexible" edge frames exhibit higher ductility demands and interstory drifts than the "stiff" edge frames. We note that the same results were reported in an earlier study for reinforced concrete buildings and are the opposite of what was predicted in several other studies based on the over simplified, hence very popular, one-story, shear-beam type models. The substantial differences in such demands between the two sides suggest a need for reassessment of the pertinent code provisions. In a follow up paper, a design modification will be introduced that can lead to a more uniform distribution of ductility demands in the elements of all building edges. This investigation is another step towards more rational design of non-symmetric steel buildings.

LEX가 델타형 날개의 와류 유동장에 미치는 영향 (Effects of LEX on the Vortex Field over a Delta Wing)

  • 백승욱;손명환
    • 한국군사과학기술학회지
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    • 제5권2호
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    • pp.83-90
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    • 2002
  • An experimental study was conducted to investigate the effects of a leading edge extension(LEX) on the vortex flow field over a delta wing by measuring the total pressure distribution in a subsonic wind tunnel. Freestream velocity was 40m/sec and Reynolds number per meter was $1.76{\times}10^6$. The wing with the LEX experienced a strong interaction between the LEX and wing vortices. As the angle of attack increased, the coupled vortex field of these two vortices maintained its strength and concentricity much better than the vortex field over the wing without the LEX.

Electronic structure studies of CoFeRO (R=Hf,La,Nb) thin films by X-ray absorption spectroscopy

  • Song, J.H.;Gautam, S.;Chae, K.H.;Asokan, K.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.378-378
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    • 2010
  • We report the electronic structure of CoFeO-R (R=Hf, La, Nb) thin films studied by x-ray absorption spectroscopy (XAS). These ferrites thin films were prepared by pulsed laser deposition method and characterized by XAS measurements at O K-, Co and Fe L-edges. The O K-edge spectra suggest that there is a strong hybridization between O 2p and 3d electrons of transition metal cations and Fe $L_{3,2}$-edge spectra indicate that Fe-ions exist in $Fe^{2+}$ with tetrahedral site of the spinel structure. Divalent Co ions is also distributed in tetrahedral site with rare earth ions goes to octahedral sites of spinel structure. X-ray magnetic circular dichroism (XMCD) is also used to explain the symmetry and magnetic nature dependence on rare-earth ions.

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On the Basis Number of the Semi-Strong Product of Bipartite Graphs with Cycles

  • Jaradat, M.M.M.;Alzoubi, Maref Y.
    • Kyungpook Mathematical Journal
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    • 제45권1호
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    • pp.45-53
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    • 2005
  • A basis of the cycle space C (G) is d-fold if each edge occurs in at most d cycles of C(G). The basis number, b(G), of a graph G is defined to be the least integer d such that G has a d-fold basis for its cycle space. MacLane proved that a graph G is planar if and only if $b(G)\;{\leq}\;2$. Schmeichel showed that for $n\;{\geq}\;5,\;b(K_{n}\;{\bullet}\;P_{2})\;{\leq}\;1\;+\;b(K_n)$. Ali proved that for n, $m\;{\geq}\;5,\;b(K_n\;{\bullet}\;K_m)\;{\leq}\;3\;+\;b(K_n)\;+\;b(K_m)$. In this paper, we give an upper bound for the basis number of the semi-strong product of a bipartite graph with a cycle.

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