• 제목/요약/키워드: Boundaries

검색결과 3,825건 처리시간 0.031초

WAVELETS ON THE UNIT INTERVAL WITH BOUNDARY TREATMENT

  • Kim, Dai-Gyoung
    • 대한수학회논문집
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    • 제12권2호
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    • pp.427-456
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    • 1997
  • This paper concerns constructing wavelet bases on the unit interval, where a new boundary treatment is provided to overcome certain drawbacks of eariler constructions. Wavelet expansions on the unit interval usually suffer from artificial boundary effects and poor convergence at the boundaries. Many researchers have suggested a solution to the drawbacks. From a practical point of view, their solutions also have a common disadvantage. This paper provides a new solution using biorthogonality near the boundaries, that avoids the disadvantage while preserving their advantages.

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HOMOGENEOUS POLYNOMIAL HYPERSURFACE ISOLATED SINGULARITIES

  • Akahori, Takao
    • 대한수학회지
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    • 제40권4호
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    • pp.667-680
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    • 2003
  • The mirror conjecture means originally the deep relation between complex and symplectic geometry in Calabi-Yau manifolds. Recently, this conjecture is posed beyond Calabi-Yau, and even to, open manifolds (e.g. $A_{n}$ singularities and its resolution) is discussed. While if we treat open manifolds, we can't avoid the boundary (in our case, CR manifolds). Therefore we pose the more precise conjecture (mirror symmetry with boundaries). Namely, in mirror symmetry, for boundaries, what kind of structure should correspond\ulcorner For this problem, the $A_{n}$ case is studied.

Abrikosov 볼텍스에 의한 결정입계 볼텍스의 속박 현상 (Possible pinning of grain-boundary vortices by neighboring Abrikosov vortices in the nearby grains)

  • 김동호
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.1-5
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    • 1999
  • The critical currents I$_c$ of the YBCO grain boundaries of 90-degree [100] symmetric tilt showed a hysteretic behavior depending on how the external magnetic fields were applied. Near 77K for fields less than ${\sim}$1 T, the field-cooled I$_c$ of grain boundaries was larger than the zero-field-cooled I$_c$. This result is consistent with the model in which the grain-boundary vortices can be pinned by neighboring Abrikosov vortices in the nearby grains.

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무인 자동차 개발 연구 (Development of the autnomous road vehicle)

  • 최진욱;한민홍
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.88-93
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    • 1993
  • This paper introduces an ARV(Autonomous Road Vehicle) system which can run on orads without help of a driver by detecting road boundaries through computer vision. This vehicle can also detect obstacles in front through sonar sensors and infrared sensors. This system largely consists of a handle steering module and a braking module. From road boundaries, the steering module determines handle turn angle. The braking module stops or decelerates to avoid collision depending on the relative speeds and distance to the obstacles detected by different sensors. This ARV system has been implemented in a small jeep and can run 30-40 km/h city traffic. In this paper, we illustrate the structure of the ARV systems and its operation principle.

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A new object recognition algorithm using generalized incremental circle transform

  • Han, Dong-Il;You, Bum-Jae;Zeungnam Bien
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.933-938
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    • 1990
  • A method of recognizing 2-dimensional polygonal object is proposed by using a concept of generalized incremental circle transform. The generalized incremental circle transform, which maps boundaries of an object into a circular disc, represents efficiently the shape of the boundaries that are obtained from digirized binary images of the objects. It is proved that the generalized incremental circle transform of an object is invariant to object translation, rotation, and size, and can be used as feature information for recognizing two dimensional polygonal object efficiently.

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Regularity of solutions to Helmholtz-type problems with absorbing boundary conditions in nonsmooth domains

  • Kim, Jinsoo;Dongwoo Sheen
    • 대한수학회보
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    • 제34권1호
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    • pp.135-146
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    • 1997
  • For the numerical simulation of wave phenomena either in unbounded domains that it is not feasible to compute solutions on the entire region, it is needed to truncate the original domains to manageable bounded domains whose geometries are simple but usually nonsmooth. On the artificial boundaries thus created, absorbing boundary conditions are taken so that the significant part of waves arriving at the artificial boundaries can be transmitted [5,10,11,16,17,26]$.

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Two domain TN structure with stable TN boundaries

  • Hong, Hyung-Ki;Kim, Gi-Hong;Lee, Won-Ho;Ham, Mi-Suk;Shin, Hyun-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.456-458
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    • 2002
  • On the half area of a pixel, pretilt angle was decreased by UV radiation and two domain TN was induced by the pretilt difference. In this structure, ITO slit was made inside pixel electrode on the TFT substrate to stabilize domain boundaries. The result shows that this structure is more resistant to outside stress and unwanted domain deformation is prevented.

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Prosodic Features at "Sentence Boundaries" in Oral Presentations

  • Umesaki, Atsuko-Furuta
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2000년도 7월 학술대회지
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    • pp.149-164
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    • 2000
  • It is generally said that falling intonation is used at the end of a declarative sentence. However, this is not the case with all stretches of spontaneous speech which are marked in transcription as sentences. The present paper examines intonation patterns appearing at the end of declarative sentences in oral presentations, and discusses instances where falling intonation does not appear. The texts used for analysis are eight oral presentations collected at international conferences in the field of physics. Quantitative and qualitative analyses are carried out. Three major factors related to discourse structure have been found for nonoccurrence of falling intonation at sentence boundaries.

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Managing Knowledge Creating Relationships

  • Gadman, Sean
    • International Journal of Quality Innovation
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    • 제6권2호
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    • pp.46-58
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    • 2005
  • The internet is enabling a new economy based on the networking of human knowledge. While the benefits of connecting people to people, people to information and people to data within an organization are becoming more recognized and appreciated, much less is known about managing knowledge creation and dissemination across corporate boundaries. This paper addresses the challenges associated with selecting the best collaborative strategy and managing relationships which span organizational cultures and boundaries.

고강도 알루미늄합금 용접부의 고온균열 Mechanism (Mechanism of Hot Cracking in High Strength Al Welds)

  • 이창희;조성석
    • Journal of Welding and Joining
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    • 제14권3호
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    • pp.93-104
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    • 1996
  • This study evaluated relative hot cracking susceptibility of commercial aluminum alloy welds, and then suggested possible mechanisms operated in the weld fusion zone and in the heat affected zone based on the observed cracking morphologies, fractography and microstructural features. The fusion zone solidification cracking was found to be mainly due to a microsegregation of Cu, Si, and Mg in grain boundaries, while liquation cracking in the HAZ was by the incipient melting of the segregated grain boundaries and the consitutional liquation of large aging precipitates and intermetallic compounds in the partially melted zone adjacent to the fusion line which experienced a rapid thermal excursion during welding.

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