• Title/Summary/Keyword: 프랙탈(fractal) 구조

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A Study on the Characteristics of Microstrip Patch Antenna with Frequency Selective Surface with Fractal Slot (프랙탈 슬롯을 가진 주파수 선택적 평면(FSS)에 의한 마이크로스트립 패치 안테나의 특성 연구)

  • Shim, Jae-Ruen
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.7
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    • pp.1242-1246
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    • 2007
  • In this study, FSS(Frequency Selective Surface) with Koch Fractal Curve slot is positioned on the conventional single layer microstrip patch antenna. Numerical results of the proposed antenna bandwidth and the antenna gain are increased compared with those of the conventional single layer microstrip patch antenna. In the future, the fractal geometry of the slot in FSS(Frequency Selective Surface) as a supplementary microstrip patch is researched for the enhancement of the microstrip patch antenna characteristics.

Automatic Composition Algorithm based on Fractal Tree (프랙탈 트리를 이용한 자동 작곡 방법)

  • Kwak, Sung-Ho;Yoo, Min-Joon;Lee, In-Kwon
    • 한국HCI학회:학술대회논문집
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    • 2008.02a
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    • pp.618-622
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    • 2008
  • In this paper, we suggest new music composition algorithm based on fractal theory. User can define and control fractal shape by setting an initial state and production rules in L-System. We generate an asymmetric fractal tree based on L-System and probability. Then a music is generated by the fractal tree image using sonification techniques. We introduce two composition algorithm using the fractal tree. First, monophonic music can be generated by mapping x and y axis to velocity and pitch, respectively Second, harmonic music also can be generated by mapping x and y axis to time and pitch, respectively Using our composition algorithm, user can easily generate a music which has repeated pattern created by recursive feature of fractal, and a music which has structure similar to fractal tree image.

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Crack Growth Behavior of Cement Composites by Fractal Analysis (시멘트 복합체의 균열성장거동에 관한 프랙탈 해석)

  • 원종필;김성애
    • Journal of the Korea Concrete Institute
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    • v.13 no.2
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    • pp.146-152
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    • 2001
  • The fractal geometry is a non-Euclidean geometry which discribes the naturally irregular or fragmented shaps, so that it can be applied to fracture behavior of materials to investigate the fracture process. Fractal curves have a characteristic that represents a self-similarity as an invariant based on the fractal dimension. This fractal geometry was applied to the crack growth of cementitious composites in order to correlate the fracture behavior to microstructures of cemposite composites. The purpose of this study was to find relationships between fractal dimensions and fracture energy. Fracture test was carried out in order to investigate the fracture behavior of plain and fiber reinforced cement composites. The load-CMOD curve and fracture energy of the beams were observed under the three point loading system. The crack profiles were obtained by the image processing system. Box counting method was used to determine the fractal dimension, D$_{f}$. It was known that the linear correlation exists between fractal dimension and fracture energy of the cement composites. The implications of the fractal nature for the crack growth behavior on the fracture energy, G$_{f}$ is appearent.ent.

Fractal Microstrip patch Antenna Design and Fabrication for WLAN/WiMax Applications (WLAN/WiMax용 프랙탈 마이크로스트립 패치 안테나설계 및 제작)

  • Kim, Kab-Ki
    • Journal of Advanced Navigation Technology
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    • v.15 no.6
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    • pp.1008-1014
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    • 2011
  • In this paper, multi-band fractal microstrip patch antenna which is possible for WLAN band and WiMax band is designed and made. For multi-resonance of developed antenna, resonance frequency, impedance matching, polarity and reflection pattern can mad perfectly, then to make satisfied multi-independent frequency three kind of half circle fractal patch is inserted. In the situation continuously happening half circle in designed structure, antennas one of half-circle band is shown.

Quantification Analysis of Element Surface by Fractal Dimension (프랙탈 차원에 의한 소자 표면의 정량화 분석)

  • Kyung-Jin, Hong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.1
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    • pp.145-149
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    • 2023
  • High-resolution images of surfaces provide detailed information on pores or shapes with specific sizes ranging from nano sizes to micrometers. However, it is not yet clear to determine an efficient association for pores or shapes from high-resolution images of surfaces. For the efficient association of pores and shapes, the surface characteristics of the device were considered as fractal dimensions by taking SEM photographs and binarizing the images. The fractal program was directly coded for surface analysis of the device. The device surface characteristics and electrical characteristics are thought to be related to the fractal dimension. The fractal dimension decreased with an increase in internal pores. The density and grain boundary of particles, which are structural characteristics of the device surface, were related to the fractal dimension. The particle size decreased with an increase in the fractal dimension and was uniformly formed. When the particles were uniformly formed, fewer pores were present and the fractal dimension increased.

Circular Polarization of Sierpinski Fractal Triangular Antenna by Sequential Rotation Techniques (Sierpinski 프랙탈 삼각형의 Sequential 회전 기법에 의한 원형 편파 특성)

  • 심재륜
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.3
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    • pp.440-444
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    • 2002
  • A microstrip patch antenna with circular polarization based on the Sierpinski fractal geometry is proposed. The Sierpinski fractal is composed of 3 equilaterial triangular patch and is easy to produce a circular polarization by sequentially rotation techniques. The characteristics of a 1x3 antenna array from Sierpinski geometry are investigated, i.e. port isolation and AR(axial Ratio).

Characteristics of Circular Polarization of Microstrip Patch Antenna Based on the Sierpinski Fractal Equilaterial Triangular (Sierpinski 프랙탈 삼각형에 기초한 마이크로스트립 패치 안테나의 원형 편파 특성)

  • 심재륜
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.05a
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    • pp.234-237
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    • 2002
  • A microstrip patch antenna with circular polarization based on the Sierpinski fractal is composed of 3 equilaterial triangular Polarization by sequentially rotation techniques. The characteristics of a $1\times3$ antenna array from Sierpinski geometry an investigated, i.e. port isolation and AR(axial Ratio).

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Design and Fabrication of the GPS Receiving Antenna using Hilbert Curve Fractal Structure (힐버트 커브 프랙탈 구조를 이용한 GPS 수신 안테나 설계 및 제작)

  • Kang, Sang-Won
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.125-129
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    • 2014
  • In this paper, design and fabrication of the GPS receiving antenna using Hilbert curve fractal structure was proposed. The size of the antenna was miniaturized by transforming dipole structure into monopole structure because its size increases if Hilbert curve fractal dipole structure is used. To use a Hilbert curve structure, the current directions of the radiator were made oppositely each other. The size of the antenna is $10{\times}10{\times}0.8[mm]$, the line width is 0.25[mm]. The resonant frequency is 1.58[GHz] and its range is 1.52[GHz] ~ 1.65[GHz]. Frequency bandwidth is 130[MHz]. Antenna maximum gain is 3.09[dBi].

Discontinuous Fracture Characteristics and Fractal Dimensions of Groundwater Flow Section in Youngchun Waterway Tunnel (영천댐 도수로터널내 지하수 유출구간의 불연속성 단열 특성 및 단열 프랙탈 차원)

  • 이병대;추창오;이인호;정교철;함세영;조병욱
    • The Journal of Engineering Geology
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    • v.12 no.3
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    • pp.333-344
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    • 2002
  • To clarify the relationship between groundwater flow tate and statistical distribution of fractures in Youngchun waterway tunnel, the fracture characteristics and fractal dimensions of groundwater flow section were evaluated. The flow rate of 84,465m$^3$/day was identified in fault, accounting for about 70 percent of the total How rate. The flow rate of 36,525m$^3$/day was identified in joint, accounting for about 30 percent of the total flow rate. The flow late in the NATM section of sedimentary rocks increased with the fractal dimensions. The fractal dimensions determined in fault or fracture zones show more positive relation with the flow rate than those in joint developed zones.

Design Principles of Fractal Geometry as Complex System (복잡계 구조로서 프랙탈 기하학의 조형원리)

  • Lim, Eun-Young
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2004.11a
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    • pp.195-196
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    • 2004
  • Fractal geometry based upon the latest complex theory shows different features of design pattern quite different from the past. It is not yet sure which kind of effects it would bring about in the future, we think that it would help to create various spaces and organic design vision. Therefore we will look into the significances and adaptabilities in space design by studying fractal design principles of today's new model in space design

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