• Title/Summary/Keyword: scattered spaces

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ON $\mathcal{I}$-SCATTERED SPACES

  • Li, Zhaowen;Lu, Shizhan
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.3
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    • pp.667-680
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    • 2014
  • In this paper, $\mathcal{I}$-scattered spaces are introduced, and their characterizations and properties are given. We prove that (X, ${\tau}$) is scattered if and only if (X, ${\tau}$, $\mathcal{I}$) is $\mathcal{I}$-scattered for any ideal $\mathcal{I}$ on X.

SOBOLEV TYPE APPROXIMATION ORDER BY SCATTERED SHIFTS OF A RADIAL BASIS FUNCTION

  • Yoon, Jung-Ho
    • Journal of applied mathematics & informatics
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    • v.23 no.1_2
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    • pp.435-443
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    • 2007
  • An important approach towards solving the scattered data problem is by using radial basis functions. However, for a large class of smooth basis functions such as Gaussians, the existing theories guarantee the interpolant to approximate well only for a very small class of very smooth approximate which is the so-called 'native' space. The approximands f need to be extremely smooth. Hence, the purpose of this paper is to study approximation by a scattered shifts of a radial basis functions. We provide error estimates on larger spaces, especially on the homogeneous Sobolev spaces.

Using reverberation time to evaluate the amount of scattered sound energy from a tree (잔향시간지표를 이용한 나무의 음향확산성 평가)

  • Yang, Hong-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.04a
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    • pp.141-144
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    • 2014
  • In urban spaces surrounded by buildings, trees could disperse sound energy, which affect sound level distribution and street canyon reverberation. Therefore, this paper examines the amount of scattered sound energy from a tree in open field by means of a reverberation time (RT). Five trees of different species and crown sizes were considered. The influential factors include crown size and shape, foliage condition, and source-receiver distance. The results show that RT is proportionally increased with the increase of tree crown sizes, which is the most determining factor. The maximum RT measured was 0.34 sec at 4000 Hz for the studied trees in leaf. The presence of leaves increased RT at high frequencies, typically by 0.14 sec at 4000 Hz. With increasing source-receiver distance within 40 m, RT was slightly changed.

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An Exploratory Study on Urban Parks and Green Space System in Terms of the Open Space Network - Focused on the City of Daejeon - (오픈스페이스 네트워크 측면에서의 도시공원녹지체계에 관한 탐색적 연구 - 대전광역시를 대상으로 -)

  • Lee, Shi-Young;Lim, Byong-Ho;Shim, Joon-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.5
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    • pp.53-63
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    • 2009
  • This study aims at presenting a plan to build an open space network system in the city of Daejeon, assuming that parks and the green space system as a broad concept are to make a network by connecting open spaces such as parks, green spaces, squares, pedestrian roads, historical spots, etc. In the case of old downtown in Daejeon, this study examined the possibility of applying an open space network in the city of Daejeon and categorize them according to the findings from examining the case area, which enables to make a plan for building an open space network system in Daejeon. As a result, public offices and business buildings as an active open space have public open spaces in front of buildings and these front public open spaces are connected to pedestrian roads(gray open space). Since these pedestrian roads are consequently connected to large parks and rivers(green or blue open space), this overall spatial sequence can form an open space system. In addition, parks and green spaces, which have been fundamental elements so far, exist in relatively small and scattered areas at the center of the city. Hence, more parks and green space are needed to improve a park and green space system. However, it is very difficult to create new parks and green spaces in downtown, especially in old downtown areas. Therefore making an open space network system which spreads out over the whole city will form a healthy open space network in the downtown area.

Elastic Wave Propagation in Monoclinic System Due to Transient Line Load

  • Kim, Yong-Yun
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.2E
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    • pp.53-58
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    • 1998
  • In this paper, we study the response of several anisotropic systems to buried transient line loads. The problem is mathematically formulated based on the equations of motion in the constitutive relations. The load is in form of a normal stress acting with arbitrary axis on the plane of monoclinic symmetry. Plane wave equation is coupled with vertical shear wave, longitudinal wave and horizontal shear wave. We first considered the equation of motion in reference coordinate system, where the line load is coincident with symmetry axis of the orthotrioic material. Then the equation of motion is transformed with respect to general coordiante system with azimuthal angle by using transformation tensor. The load is first described as a body force in the equations of the motion for the infinite media and then it is mathematically characterized. Subsequently the results for semi-infinite spaces is also obtained by using superposition of the infinite medium solution together with a scattered solution from the free surface. Consequently explicit solutions for the displacements are obtained by using Cargniard-DeHoop contour. Numerical results which are drawn from concrete examples of orthotropic material belonging to monoclinic symmetry are demonstrated.

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The Role of Electronic Trade Specialized Service Provider under Global Trade Environment

  • Lee, Bong Soo
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.60
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    • pp.235-255
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    • 2013
  • This thesis examines the problems faced in the electronic trade specialized service provider for which improvements are necessary, and suggests various ways of overcoming those problems. First, from the legal aspect, it is necessary to clarify the scope of duties as well as to expand the threshold for entrance and business areas through the amendment of related laws. Second, from the operating aspect, the e-trade specialized service provider should be able to provide convenient work spaces through user-centered interface by connecting, integrating, automating and simplifying various services scattered around through the establishment of an operating system. Third, from the institutional aspect, trade firms should be able to perform e-trade duties without difficulties by specializing and increasing the size of the e-trade specialized service provider system and strengthening job competence. For this, it is required to improve legal registration requirements to enhance the reliability of the e-trade specialized service provider system and secure its financial capacity.

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Cases of Tracheopathia Osteochondroplastica in German shepherd (German shepherd에서 발생한 기관 골.연골형성증)

  • 한정희;김준기;서강문
    • Journal of Veterinary Clinics
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    • v.17 no.1
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    • pp.129-133
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    • 2000
  • Based on pathological findings, 5 German shepherds, revealed a mean age of 7.6 years, showing no clinical signs were diagnosed as tracheopathia osteochondroplastica(TOC). Grossly, multiple small-sizecd nodules, appeared as cobble-stones, on the cartilage rings situated in the anterior trachea and the mucosal surface of the epiglottis were showed. Numerous tiny nodules were scattered on the pleural surface of the lung. The vascular walls of the heart were irregular and coarse apearance with calcification. Histopathologically, nodules in the trachea represented an irregular expansion of the underlying tracheal ring with protrusion into the submucosa and consisted of proliferated and calcified cartilage and bone with marrow spaces containing numbers of hematopoietic cells. Pulmonary calcinosis and calcification of the vascular walls of the heart were observed. Our observations suggested that TOC arises form eccondroses and exostoses of the tracheal cartilage rings.

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Fine Needle Aspiration Cytology of Unusual Epidermoid Cyst with Diffuse Parakeratosis and Aggressive Growth - A Case Report - (미만성 이상각화증을 동반한 침습성 표피양 낭의 세침흡인 세포학적 소견 - 1예 보고 -)

  • Nam, Hae-Joo
    • The Korean Journal of Cytopathology
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    • v.10 no.1
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    • pp.85-89
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    • 1999
  • An extremely unusual case of epidermoid cyst showing diffuse parakeratosis and aggressive clinical behavior is presented. A destructive bone lesion with surrounding ill-defined soft tissue lesion was found by computed tomography in a 63 year-old man complaining of painful swelling of the right buttock. He had a history of surgical excision twice for epidermoid cysts of soft tissue of the right hip during recent one year On aspiration cytology, the aspirate was highly cellular and mostly composed of desquamated nucleated squamous cells. Operation finding revealed that the iliac bone was Irregularly destroyed and filled with gray-white cheesy material and necrotic bone bedris. Adjacent gluteus muscle showed scattered gray-white lesions. The curettage specimen showed bone necrosis and desquamated squamous cells filling the marrow spaces. The lesion within muscle revealed epidermoid cyst with diffuse parakeratosis.

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Fine Needle Aspiration Cytology of Eccrine Spiradenoma -Report of a Case- (에크린 땀샘종의 세침흡인 세포소견 -1예 보고-)

  • Kim, Dong-Ja
    • The Korean Journal of Cytopathology
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    • v.16 no.2
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    • pp.98-101
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    • 2005
  • Eccrine spiradenoma is a rare adnexal tumor of the skin and its cytomorphology has seldom been described in literature. To evaluate the cytologic features and diagnostic pitfalls of eccrine spiradenoma, we report a case of 33-year-old male whose clinical presentation was a painful subcutaneous mass at the right preauricular area. Fine needle aspirates revealed tight clusters of multilayered, uniform, cuboidal cells arranged around hyalinized perivascular spaces. Some epithelial cells showed tubules or rosette formations. The background showed scattered, naked nuclei. The histologic findings confirmed the eccrine spiradenoma. The recognition of peculiar cytologic features and clinical correlation could be helpful in the diagnosis of skin adnexal tumors.

Dynamic Responses in Orthotropic Media Due to Pulsating Line Source

  • Kim, Yong-Yun
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.1E
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    • pp.70-75
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    • 1998
  • The analysis of dynamic responses are carried out on several anisotropic systems due to buried pulsating line sources. These include infinite, semi-infinite spaces. The media possess orthotropic or higher symmetry. The load is in the from of a normal stress acting with parallel to symmetry axis on the plane of symmetry within the materials. The results are first derived for infinite media. Subsequently the results for semi-infinite are derived by using superposition of the solution in the infinite medium together with a scattered solution from the boundaries. The sum of both solutions has to satisfy stress free boundary conditions, thereby leading to the complete solutions. The solutions are simplified to the systems possessing of higher symmetry, such as orthotropic, transversely isotropic, cubic, and isotropic symmetry.

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