• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.9 s.100
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• pp.949-956
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• 2005

In this paper, a new CPW-fed cross shape fractal antenna having a self-affinity is presented. This novel configuration, which has anisotropic scaling symmetry, makes smaller profile characteristic compared to the fractal antenna using a self-similarity. Increase of the iteration coefficient, which leads to decrease of the fundamental resonant frequency, shows a good impedance matching condition and multi-band characteristics due to new surface current paths. The radiation patterns are similar to those of monopole antennas. In the K3 stage of iteration, the proposed antenna shows a measured maximum gain 2.27 dBi at 940 MHz. A commercially available software based on the FDTD algorithm has been used to obtain the predicted results. In addition, an RT/Duroid 5880 substrate has been employed for the experimental results.

• Spatial Information Research
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• v.8 no.2
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• pp.243-255
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• 2000

The spatial distribution characteristics and patterns of geographic features in space can be understood through a variety of analysis techniques. The scale is one of most important factors in spatial analysis techniques. This study is aimed at identifying the characteristics of spatial data with a coarser spatial resolution and finding procedures for spatial resolution in operational scale. To achieve these objectives, this study selected LANSAT TM imagery for Sunchon Bay, a coastal wetland for a study site, applied the indices for representing scale characteristics with resolution, and compared those indices. Local variance and fractal dimension developed by previous studies were applied to measure the textual characteristics. In this study, Moran s I was applied to measure spatial pattern change of variance data which were generated from the process of coarser resolution. Drawing upon the Moran s I of variancedata was optimum technique for analysing spatial structure than those of previous studies (local variance and fractal dimension). When the variance data represents maximum Moran´s I at certainly resolution, spatial data reveals maximum change at that resolution. The optimum resolution for spatial data can be explored by applying these results.

• Journal of Digital Convergence
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• v.17 no.6
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• pp.365-371
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• 2019

In this study, VR contents were produced by using the rose which is the material of the tomb of the surrealistic work wrestler of Rene Magritte, an artistic genre, as a motive. In conclusion, the distortion (spatial modulation) of the image scale is connected to the dynamic-curve and texture-soft areas, and the superposition (combination of contradictory images) is called the big-size, irregular-depth area, Are connected to the positions of big-size and irregular-space regions. The theme of the work was Dream, and the plants and roses patterns were produced in each timeline, and overlap, scale, distortion, overlap, distortion, and scale were used.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.333-338
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• 2001

Fractal geometry is a non-Euclidean geometry which has been developed to quantitative analysis irregular or fractional shapes. Fractal dimension of irregular surface has fractal values ranging from 2 to 3 and of irregular line profile has fractal values ranging from 1 to 2. In this paper, quantitative analysis of crack growth patterns during the fracture processing of fiber-reinforced cement composites based on fractal geometry. The fracture behaviors of fiber reinforced mortar beams subjected to three-point loading in flexure. The beams all had a single notch depth, but varing volume fractions of polypropylene, cellulose fibers. The crack growth behaviors, as observed through the image processing system, and the box counting method was used to determine the fractal dimension, Df. The results showed that the linear correlation exists between fractal dimension and fracture energy of the fiber reinforced cement mortar.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.39-43
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• 2008

경관을 구성하는 다양한 요소들의 공간적 분포 패턴과 상호 관계를 정량적으로 분석하기 위하여 다양한 경관지수가 개발되어 사용되고 있다. 경관구조 및 변화특성을 정량적으로 해석하기 위한 노력은 1950년대 후반부터 기하학적 이론을 기초로 하여 제기되어 왔으며, 최근에는 원격탐사, GIS, 정보이론, 프랙탈 이론에 근거한 지표 등이 도입되어 사용되고 있다. 본 연구에서는 연안습지 식생의 발달과 분포 특성을 공간적으로 해석하기 위해 Landsat 영상에 분광혼합분석 기법을 적용하여 선정한 지표면 식생비율을 10개 클래스로 구분한 후 각 클래스에 대해 경관지수를 적용하여 식생비율의 시-공간적 변동 특성을 분석하였다. 새만금방조제를 비롯한 많은 연안습지에 생성되는 습지식생의 공간적 분포를 변화탐지 하고 이들의 시-공간적 분포에 영향을 미치는 요인을 해석하여 연안습지의 보존과 개발에 대한 기초 정보를 위성자료를 통해 추출 분석하였다.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.57-58
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• 2006

과거 2003년 북미 대 정전 이후 전력기기의 사고 발생 후 얼마나 빨리 사고를 제거하고 피해가 적도록 신속하게 복구하는 개념에서 사고이전에 사고를 미연에 방지하는 예방개념으로 관심이 높아지고 있다. 전력기기를 사고로부터 보호하는 보호기기도 중요하지만 사고이전의 상태를 감시하여 미연에 사고를 방지할 수 있도록 하는 예방진단시스템의 중요성도 높아지고 있다. 이렇듯 관심이 높아짐에 따라 각종 진단알고리즘의 개발이 신속히 이루어지고 있다. 보호기기처럼 어떤 설정된 정정 값 이상의 값이 입력되면 보호동작을 수행하는 단순 동작과는 달리 예방진단 시스템은 입력되는 신호의 패턴을 인식하여 열화/노화 등의 진행상황 및 정비조치에 대한 정보를 만들므로 인공지능적인 요소가 많이 적용되고 있다. 따라서 각종 Fuzzy, Neural Network, Expert 등 각종 판단 알고리즘과 패턴을 인식하는 확률통계, 프랙탈 기하학 등이 적용되고 있다. 모두가 틀리다는 것은 아니지만 보다 정확한 예방진단을 위해 각종 알고리즘이 추가 및 수정이 자주이루어지고 있는 실정이다. 그러나 새로운 알고리즘을 적용하기 위해서 기 개발되어 운영 중이거나 설치된 예방진단시스템을 멈추고 전반적으로 수정을 수행하는 것은 감시진단시스템의 본래 모습을 무시하는 행동이라고 할 수 있다. 본 연구에서는 이런 문제를 해결하기 위하여 온라인 상태에서 장비를 감시하는 예방진단 시스템의 알고리즘 변형 시 시스템의 운영이 문제되지 않도록하는 다이나믹 인터페이스를 개발하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.712-715
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• 1999

Treeing has a profit to observe processing electrical breakdown because it gives degradation steps of insulation material by optical method. But, reappearance properly of treeing is not so good and precise quantization of tree growth is not so easy because tree Patterns are very complicate. The study on tree growth using image processing is predicted to precision of tree degradation and possible to quality measurement of tree pattern. In this paper, degradation steps are analyzed by image processing, therefore precision and realiability of tree growth are increased. Also, processing of tree degradation is quantized by fractal.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.9
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• pp.921-932
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• 2010

This paper presents a dual-band array antenna based on a modified Sierpinski fractal structure. Array structure is mirror symmetric, and forms broadside radiation pattern for dual frequency band if the ports are fed with $180^{\circ}C$ phase difference between upper and lower $2{\times}1$ array. To use in-phase corporate feeding circuit, the phase inversion structure is designed by changing the position of patch and ground for upper and lower array. The dimensions of the array antenna is $28{\times}30{\times}5\;cm^3$ and the bandwidth of 855~1,380 MHz(47 %), 1,770~2,330 MHz(27 %) were achieved for -10 dB return loss. The measured gain is 9.06~12.44 dBi for the first band and 11.76~14.84 dBi for the second band. The half power beam width is $57^{\circ}$ for x-z plane and $46^{\circ}$ for y-z plane at 1,100 MHz and $43^{\circ}$ and $28^{\circ}$ at 2,050 MHz, respectively.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.55-56
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• 2006

In prevention and diagnostic system of GIS, pattern classification is focused on the detection of unnatural patterns in PD(Partial discharge) image data. Fractals have been used extensively to provide a description and to model mathematically many of the naturally occurring complex shapes, such as coastlines, mountain ranges, clouds, etc., and have also received increased attention in the field of image processing, for purposes of segmentation and recognition of regions and objects present in natural scenes. Among the numerous fractal features that could be defined and used for image data, fractal dimension and lacunarity have been found to be useful for recognition purposes Partial discharge(PD) occuring in GIS system is a very complex phenomenon, and more so are the shapes of the various 2-d patterns obtained during routine tests and measurements. It has been fairly well established that these pattern shapes and underlying defects causing PD have a 1:1 correspondence, and therefore methods to describe and qunatify these pattern shapes must be explored, before recognition systems based on them could be developed. The computed fractal features(fractal dimension and lacunarity) for standard library of PD data were analyzed and found to possess fairly reasonable pattern discriminating abilities. This new approach appears promising, and further research is essential before any long-term predictions can be made.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4831-4843
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• 2014

Magazines on specific genres have been operating collaborative, co-working and collective production systems for value maximization using an adaptation strategy on the dynamic, complex and uncertain value network of the magazine industry. The study used a case study method, and data collection was performed by observational research, depth interviews and survey research. The subjects of the study were 'magazine industry', 'magazine firm and community', and 'collaboration system within creative users'. According to the research results, the ecosystem of magazines on a specific genre has been evolving into an innovative value network system, which is combined with the magazine firm, community users and magazine platform. Second, the rapid introduction of smart device environment changes the way of the collaborating system, in which an action and interaction came out within the community, creative users and magazine firms. Third, the production agency shows strong action and interaction, which fits the magazine platform within the ecosystem of a magazine on a specific genre well. This model has a similar fractal structure to the game, publishing, drama, movie, comic, and animation contents industry, converging to an innovative technology-based-creative-industry.