• Title/Summary/Keyword: natural pattern

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Spatial Point-pattern Analysis of a Population of Lodgepole Pine

  • Chhin, Sophan;Huang, Shongming
    • Journal of Forest and Environmental Science
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    • v.34 no.6
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    • pp.419-428
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    • 2018
  • Spatial point-patterns analyses were conducted to provide insight into the ecological process behind competition and mortality in two lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) stands, one in the Lower Foothills, and the other in the Upper Foothills natural subregions in the boreal forest of Alberta, Canada. Spatial statistical tests were applied to live and dead trees and included Clark-Evans nearest neighbor statistic (R), nearest neighbor distribution function (G(r)), and a variant of Ripley's K function (L(r)). In both lodgepole pine plots, the results indicated that there was significant regularity in the spatial point-pattern of the surviving trees which indicates that competition has been a key driver of mortality and forest dynamics in these plots. Dead trees generally showed a clumping pattern in higher density patches. There were also significant bivariate relationships between live and dead trees, but the relationships differed by natural subregion. In the Lower Foothills plot there was significant attraction between live and dead tees which suggests mainly one-sided competition for light. In contrast, in the Upper Foothills plot, there was significant repulsion between live and dead trees which suggests two-sided competition for soil nutrients and soil moisture.

The Color Effect of Half-linen by DTP with Natural Ink - Apply Floral Textile Design with Motif of Korean Endemic Plants - (천연 잉크로 DTP한 half-linen의 색상 효과 - 한국 고유식물을 모티프로 한 텍스타일 디자인 적용 -)

  • Sim, Juyeon;Park, Youngmi
    • Textile Coloration and Finishing
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    • v.33 no.4
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    • pp.220-229
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    • 2021
  • This study is aimed to a textile design with a motif of korean endemic plants and a method for printing it in an eco-friendly manner. The floral pattern with the motif of korean endemic plants was designed using Illustrator and Photoshop program. CMYK color, which is the basic color of Digital Textile Printing (DTP), is based on natural dyes, and various colors, achromatic colors and pastel tones are applied. As a result, half-linen and cotton were suitable as a result of designing and applying a floral pattern of a korean special plants. Also, as a result of analyzing the printing effect by colorway and DTP for each material, it was printed uniformly and the washing fastness was good. However, fastness of color change showed low, indicating that a follow-up study was needed. This study contributes to environmental conservation through eco-friendly printing and the korean endemic plants will be interested in people around the world beyond korea.

Modal characteristics of partially perforated rectangular plate with triangular penetration pattern

  • Jhung, Myung J.;Jeong, Kyeong H.
    • Structural Engineering and Mechanics
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    • v.55 no.3
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    • pp.583-603
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    • 2015
  • There are so many applications of perforated pates with various penetration patterns. If they are penetrated regularly, it can be represented by solid plate with equivalent material properties, which has a benefit of finite element modelling and reducing computation time for the analysis. Because the equivalent material properties suggested already are not proper to be applicable for the dynamic analysis, it is necessary to extract the equivalent material properties for the dynamic analysis. Therefore, in this study, the equivalent modulus of elasticity are obtained for the perforated plate with a triangular penetration pattern by comparing the natural frequencies of the perforated plate with those of solid plate, which are represented with respect to the ligament efficacy. Using the equivalent material properties suggested, the modal analyses of the partially perforated rectangular plate with a triangular penetration pattern are performed and its applicability is shown by comparing natural frequencies of perforated and homogeneous solid plates from finite element method and analytical method.

Analysis of Vibration Characteristics by Using Electro-Optic Holography Method (전자광학 Holography법을 이용한 진동 특성 해석)

  • 김경석;차용훈;김형택;정현철;양승필;김정호
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.98-104
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    • 1998
  • Recently. a new technique called Electronic Speckle Pattern Interferometry(ESPI) has been developed to overcome the drawbacks of existing holography. This technique enable real-time interference fringes to be displayed directly on TV monitor without recourse to any form of photographic processing. This research was carried out for the purpose of applying the vibration analysis method employing Electronic Speckle Pattern Interference technique to the vibration analysis of uniform rectangular cantilever plate. The natural vibration frequencies found by ESPI were in fair agreement with theoretical eigen frequencies acquired using theoretical formula G. B. Warburton proposed.

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Pattern-Analysis of Panax ginseng Polysaccharide (고려인삼 다당류의 패턴-분석)

  • Han, Yong-Nam;Kim, Sun-Young;Lee, Hee-Joo;Hwang, Woo-Ik;Han, Byung-Hoon
    • Journal of Ginseng Research
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    • v.16 no.3
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    • pp.217-221
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    • 1992
  • Total polysaccharide contents in Panax ginseng roots were evaluated by a spectrophotometry, utilizing the complex formation of ginseng polysaccharide with alcian blue dye in 50 mM ammonium biphosphate, pH 4.2. The total polysaccharide content in red ginseng was about three times higher than that in fresh ginseng when both were extracted with water, and was increased about two times when red ginseng was extracted with an alkaline solution. The determination of total polysaccharide in various parts of ginseng revealed that main roots contained the component more than fine roots. Fresh ginseng sections stained by the dye showed polysaccharide mainly found in cortex and cambium but not in epidermis. Pattern-analysis on total and acidic polysaccharides from fresh and red ginsengs exhibited that the chemical compositions of the polysaccharides extracted from both ginsengs quite differed from each other.

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SPEECH SYNTHESIS USING LARGE SPEECH DATA-BASE

  • Lee, Kyu-Keon;Mochida, Takemi;Sakurai, Naohiro;Shirai, Katasuhiko
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1994.06a
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    • pp.949-956
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    • 1994
  • In this paper, we introduce a new speech synthesis method for Japanese and Korean arbitrary sentences using the natural speech data-base. Also, application of this method to a CAI system is discussed. In our synthesis method, a basic sentence and basic accent-phrases are selected from the data-base against a target sentence. Factors for those selections are phrase dependency structure (separation degree), number of morae, type of accent and phonemic labels. The target pitch pattern and phonemic parameter series are generated using those selected basic units. As the pitch pattern is generated using patterns which are directly extracted form real speech, it is expected to be more natural than any other pattern which is estimated by any model. Until now, we have examined this method on Japanese sentence speech and affirmed that the synthetic sound preserves human-like features fairly well. Now we extend this method to Korean sentence speech synthesis. Further more, we are trying to apply this synthesis unit to a CAI system.

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A Study on the Vibration Characteristics Analysis of Composite Materials by Using Electronic Speckle Pattern Interferometry Method (전자처리 스페클 패턴 간섭법(ESPI)을 이용한 복합재료의 진동 특성 해석에 관한 연구)

  • 김경석;정성균;정현철;양승필;김형택;김동일;이승환
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.9
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    • pp.68-74
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    • 1998
  • The ESPI(Electronic Speckle Pattern Interferometry) is a real time, full-field, non-destructive optical measurement technique that allows static and dynamic deformation analysis and surface shape measurements of engineering structures. e .g. turbine blades. vehicle engine components, body panels, etc. This technique is very similar to holographic interferometry, but uses a solid static camera and an image processing board for recording and digital processing of speckle patterns. In this paper it is presented that FEM results for the free vibration of symmetrically laminated composite as [30/-30/90]s. The natural frequencies of laminated composite rectangular plates having the particular boundary condition are experimentally obtained. In order to demonstrate the validity of the experiment, FEM analysis using ANSYS was performed and natural frequencies experimentally obtained is compared with calculation by FEM analysis. The results obtained from both experiment and FEM analysis show a good agreement.

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Experimental Modal Analysis of Perforated Rectangular Plates Submerged in Water (물에 잠긴 다공 직사각평판의 실험적 모드 해석)

  • Yoo, Gye-Hyoung;Lee, Myung-Gyu;Jeong, Kyeong-Hoon;Lee, Seong-Cheol
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.416-421
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    • 2002
  • This paper dealt with an experimental study on the hydro-elastic vibration of clamped perforated rectangular plates submerged in water. The penetration of holes in the plates had a triangular pattern with P/D (pitch to diameter) 1.750, 2.125, 2.500, 3.000 and 3.750. The natural frequencies of the perforated plates in air were obtained by the analytical method based n the relation between the reference kinetic and maximum potential energy and compared with the experimental results. Good agreement between the results was found for the natural frequencies of the perforated plates in air. It was empirically found that the natural frequencies of the perforated plate in air increase with an increase of P/D, on the other hand, the natural frequencies of the perforated plate in contact with water decrease with an increase of P/D. Additionally, the effect of the submerged depth on the natural frequency was investigated.

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Experimental Modal Analysis of Perforated Rectangular Plates Submerged In Water (물에 잠긴 다공 직사각평판의 실험적 모드 해석)

  • 유계형;이명규;정경훈;이성철
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.13 no.1
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    • pp.70-78
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    • 2003
  • This paper dealt with an experimental study on the hydroelastic vibration of clamped perforated rectangular plates submerged in water. The penetration of holes in the plates had a triangular pattern with P/D (pitch to diameter) 1.750, 2.125, 2.500, 3.000 and 3.750. The natural frequencies of the perforated plates in air were obtained by the analytical method based on the relation between the reference kinetic and maximum potential energy and compared with the experimental results. Good agreement between the results was found for the natural frequencies of the perforated plates in air. It was empirically found that the natural frequencies of the perforated plate in air increase with an increase of P/D, on the other hand, the natural frequencies of the perforated plate in contact with water decrease with an increase of P/D. Additionally. the effect of the submerged depth on the natural frequency was investigated.

Surface Error Generation of Freeform Mirror Based on Zernike Polynomial for Optical Performance Prediction

  • Lee, Sunwoo;Park, Woojin;Han, Jimin;Ahn, Hojae;Kim, Yunjong;Lee, Dae-Hee;Kim, Geon Hee;Pak, Soojong
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.67.2-67.2
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    • 2020
  • Not only the magnitude of the mirror surface error, the pattern matters as it produces certain aberrations. In particular, the surface error of the freeform mirrors, which are optimized to eliminate specific aberrations, might show much higher sensitivity in optical performance. Therefore, we analyze the mirror surface error with Zernike polynomials with the goal of generating a realistic error surface. We investigate the surface error of the freeform mirror fabricated by diamond turning machine to analyze the realistic tendency of the error. The surface error with 0.22 ㎛ root-mean-square value is fitted to the Zernike terms using the incremental fitting method, which increases the number of the fitting coefficients through steps. Furthermore, optical performance via surface error pattern based on Zernike terms is studied to see the influences of each term. With this study, realistic error surface generation may allow higher accuracy not only for the feasibility test but also for all tests and predictions using optical simulations.

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