• Title/Summary/Keyword: Fringe analysis

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A Study on the Urban Fringe Landscape Environment Model -The Analysis of Change in Land Uses of Chonan City using Landsat TM Data- (도농통합지역의 녹지환경정비모델에 관한 연구 I - 위성데이타를 이용한 천안시 토지이용 변화 -)

  • 심우경;이진희;김훈희
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.237-248
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    • 1998
  • Landcover has been largely influenced by human activities, especially in recent days. The analysis of the change of land use by urbanized development is useful for determining development plan hereafter. This study aimed to the quantitative analysis about the urban sprawl within 12 years from 1985 to 1996, at Chonan, and for extracting the characteristics of change. For this purpose, this study performed land cover classifications using Landsat TM data . A hybrid classification method was used to classify satellite images into seven types of land cover. Road network digitied from 1:25,000 topographic map was rasterized and overlaid on the landcover map. A result of this study showed that area of forest and paddy decreased due to urban sprawl. Especially from 1993 to 1996, the change of land use progressed rapidly because of merging a city and a country in Chonan. The size of patch in forest had been smaller and irregular form. It is a general progress that size of patch in forest had been smaller and irregular form. It is a general progress that the forest have changed the paddy and bare land paddy and bare land have changed low-density urban or high-density urban. This explained how urbanized Chonan was and applied the suggeston of plan in landuse with the result of this study.

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Quantitative Analysis of Holographic Fringe by using Phase Shifting Method (홀로그래피 간섭무늬 해석을 위한 위상변위법 응용연구)

  • 박승옥;권영하;고영욱;강대임
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.07a
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    • pp.73-77
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    • 1990
  • 홀로그래피 간섭무늬로부터 변형의 요철방향을 구하기 위하여 위상변위방법을 응용하였다. 위상변위법에 의하여 물체파의 위상을 변화시켜 이에따른 홀로그래피 간섭무늬의 이동을 측정하였다. 간섭무늬가 일정지점을 중심으로 좌우로 이동하는 현상으로부터 변형의 요철방향을 파악하고 최대지점의 위치를 구할 수 있었다.

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A Frequency Characteristic Analysis of Digital Hologram in Fresnel Transform Domain (Fresnel 변환영역에서 디지털 홀로그램의 주파수 특성분석)

  • Choi, Hyun-Jun;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1505-1511
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    • 2012
  • Since digital hologram includes an amount of data as can be seen at the process of digitization, it is necessary that the data representing digital hologram is reduced for storing, transmission, and processing. As the efforts that are to handle hologram with a type of digital information have been increased, various methods to compress digital hologram called by fringe pattern are groped. Suitable proposal is encoding of digital hologram. This paper analyzed the properties of digital hologram using tools of frequency transform, assuming that a generated digital hologram is a 2D image by introducing Fresnel Transform. The analysis results of digital hologram to be proposed in this paper are being expected to be used as the core techniques for an encoding of digital hologram.

A Photoelastic Study on the Stress Intensity Factor of Circular Disk with an Are-crack (광탄성법에 의한 원고형상크랙을 갖는 원판의 응력확대계수에 관한 연구)

  • Lee, Chi-Woo;Kim, Tae-Gyu;Yang, Jang-Hong;O, Se-Uk
    • Journal of Ocean Engineering and Technology
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    • v.2 no.2
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    • pp.96-103
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    • 1988
  • The stress distribution in the vicinity of the crack tip in the fracture mechanics is ordenarily indicated by the stress intensity factor. In the analysis of stress intensity factors, there are many theoretical and experimental methods. The stress analysis in photoelastic technique is usually made by using the difference of the principal stress of isochromatic fringe patterns. In this paper, the teflon molding technique is adopted to make a test specimen with a circular arc-crack, and that upgraded the accuracy of experiment. As the result, the experimental values of the stress intensity factors for the circular disk with a straight crack are coincided with the theoretical values. But, there is quite a difference between this expermental results on the finite plate for circular arc-crack and its theoretical values on the infinite one. Therefore, a boundary condition with regard to the loading condition on finite disk must be considered.

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The Type and Structure of Men's Belt in Early-Middle of Chosun Era (조선 초·중기 출토 허리끈의 유형과 구조 - 여산 송씨 출토 허리끈을 중심으로 -)

  • Son, Hee-Jin;Kwo, Young-Suk
    • Fashion & Textile Research Journal
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    • v.13 no.5
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    • pp.672-678
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    • 2011
  • This was written based on the type and structure of korean man's waist belt in the early and middle era of the Chosun era. The waist belt was excavated from the Mokdaldong in the Daejeon city. The types of korean man's waist belt in the Chosun era were classified into Wondahae (i.e., round shape belt) and Gwangdahae. The Wondahae consist of two types which are circle shaped and straight types. The circle shaped wondahae contain one fringe in the main body of the belt and its joint part is decorated with a small network such as lacing decoration with the size about 1 cm around. The shape of the Wondahae has been changed from the circle shaped into the straight types and also has a tendency to be wider and longer as time went by. The standard form of the Gwangdahae is straight with about 2-3 cm width and elaborated by lacelike fringe as well. This also has a tendency to be wider starting from the 1600s show. The structure of this belts were divided into braid and ornament parts. The ornament part was constructed with the lacelike netting and fringe parts. The sophisticated craft techniques have a great decorative beauty. Through an analysis of FT-IR, the materials of those three belt are known which are made of the silk and the core thread was filled with cotton. Moreover, it can be confirmed that the glitter material of the ornament part were designed with gold foil and has been analyzed with SEM-EDX.

Analysis of Photoelastic Stress Field Around Inclined Crack Tip by Using Hybrid Technique (하이브리드 기법에 의한 경사균열 팁 주위의 광탄성 응력장 해석)

  • Chen, Lei;Seo, Jin;Lee, Byung-Hee;Kim, Myung-Soo;Baek, Tae-Hyun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.9
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    • pp.1287-1292
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    • 2010
  • In this paper, a hybrid technique is presented. First, the isochromatic fringe data of a given set of points are calculated by the finite element method and are used as input data in complex variable formulations. Then the numerical model of the specimen with a central inclined crack is transformed from the physical plane to the complex plane by conformal mapping. The stress field is analyzed and the mixed-mode stress intensity factors are calculated for this complex plane. The stress intensity factors are calculated by the finite element method as well as by a theoretical method and compared with each other. In order to conveniently compare these values with each other, both actual and regenerated photoelastic fringe patterns are multiplied by a factor of two and sharpened by digital image processing.

The Characteristics of Land Use Change at the Urban Fringe - The Case of Daegu Metropolitan City - (대도시 주변 신개발지의 개발특성에 관한 연구 - 대구광역시를 사례지역으로 -)

  • Park, Sun-Hyung;Kim, Jae-Ik
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.2
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    • pp.36-46
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    • 2007
  • The primary purpose of this study is to identify the characteristics of land use change at the urban fringe. For this purpose, the Daegu Metropolitan City is selected as a study area. Land use changes between 1990 and 2000 in fringe areas are identified by processing Landsat TM5 imageries. The main findings are follows: First, land development has been driven by residential development, especially large-scale residential development encouraged by the two-million housing construction plan. Second, the type and size of the land use conversion are not identical across the study area. For example, the main land use type of the newly developed area of Buk-gu is residential use while that of Suseong-gu is public use. Third, most of residential development type is a high-density development which is quite different from American type of low-density development.

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Impact of Land Use Land Cover Change on the Forest Area of Okomu National Park, Edo State, Nigeria

  • Nosayaba Osadolor;Iveren Blessing Chenge
    • Journal of Forest and Environmental Science
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    • v.39 no.3
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    • pp.167-179
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    • 2023
  • The extent of change in the Land use/Land cover (LULC) of Okomu National Park (ONP) and fringe communities was evaluated. High resolution Landsat imagery was used to identify the major vegetation cover/land use systems and changes around the national park and fringe communities while field visits/ground truthing, involving the collection of coordinates of the locations was carried out to ascertain the various land cover/land use types identified on the images, and the extent of change over three-time series (2000, 2010 and 2020). The change detection was analyzed using area calculation, change detection by nature and normalized difference vegetation index (NDVI). The result of the classification and analysis of the LULC Change of ONP and fringe communities revealed an alarming rate of encroachment into the protected area. All the classification features analyzed had notable changes from 2000-2020. The forest, which was the dominant LULC feature in 2000, covering about 66.19% of the area reduced drastically to 36.12% in 2020. Agricultural land increased from 6.14% in 2000 to 34.06% in 2020 while vegetation (degraded land) increased from 27.18% in 2000 to 38.89% in 2020. The magnitude of the change in ONP and surroundings showed the forest lost -247.136 km2 (50.01%) to other land cover classes with annual rate change of 10%, implying that 10% of forest land was lost annually in the area for 20 years. The NDVI classification values of 2020 indicate that the increase in medium (399.62 km2 ) and secondary high (210.17 km2 ) vegetation classes which drastically reduced the size of the high (38.07 km2 ) vegetation class. Consequent disappearance of the high forests of Okomu is inevitable if this trend of exploitation is not checked. It is pertinent to explore other forest management strategies involving community participation.