• Title/Summary/Keyword: Resolution Characteristics

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The Characteristics of Computer-Generated Holographic Optical Low-Pass Filter (컴퓨터로 설계한 홀로그램 광 저대역 필터의 특성 분석)

  • 김인길;고춘수;임성우;오용호;이재철
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.12S
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    • pp.1261-1267
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    • 2003
  • Since the grating optical low-pass fillet degrades the resolution of images, we developed a hologram optical low-pass filter that show low degradation of the image and studied its characteristics. We designed the hologram that divides input beam into circular shaped 21 beams with a Monte-Carlo based hologram generation program and calculated its MTE characteristics to compare it with that of a grating filter. The hologram was manufactured through the optical lithography process and attached to a digital imaging device (Zoran 732212) for measurement. The moirfiltering is compared with zone plate images and the resolution loss is measured with USAF resolution chart. The hologram optical low-pass filter showed better characteristics in both moly filtering and resolution.

Characteristics of Multi-Spatial Resolution Satellite Images for the Extraction of Urban Environmental Information

  • Seo, Dong-Jo;Park, Chong-Hwa;Tateishi, Ryutaro
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.218-224
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    • 1998
  • The coefficients of variation obtained from three typical vegetation indices of eight levels of multi-spatial resolution images in urban areas were employed to identify the optimum spatial resolution in terms of maintaining information quality. These multi-spatial resolution images were prepared by degrading 1 meter simulated, 16 meter ADEOS/AVNIR, and 30 meter Landsat-TM images. Normalized Difference Vegetation Index (NDVI), Perpendicular Vegetation Index (PVI) and Soil Adjusted Ratio Vegetation Index (SARVI) were applied to reduce data redundancy and compare the characteristics of multi-spatial resolution image of vegetation indices. The threshold point on the curve of the coefficient of variation was defined as the optimum resolution level for the analysis with multi-spatial resolution image sets. Also, the results from the image segmentation approach of region growing to extract man-made features were compared with these multi-spatial resolution image sets.

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Gender, Cultural Disposition and Peer Conflict Resolution Strategies of Elementary School Children (초등학생의 성별, 문화성향과 친구간 갈등해결전략)

  • Kim, Eun-Jin;Lee, Hee-Yeong
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.1
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    • pp.181-191
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    • 2013
  • In this study, characteristics of cultural disposition and peer conflict resolution strategies and the relationship between cultural dispositions and peer conflict resolution strategies of elementary school children were investigated. In order to achieve this research purpose, the following research questions were established. First, what are the characteristics of cultural dispositions that children have? Second, what are the characteristics of conflict resolution strategies that children use? Third, what are the relationships between cultural dispositions and peer conflict resolution strategies? The subjects of this study were 564(283 male and 281 female) 5th and 6th graders. Research instruments used to collect data were INDCOL and Conflict Resolution Strategy Scale. Collected data were analyzed using Descriptives, t-test, Pearson's Correlation Coefficient, Cross-tabs and Two-way ANOVA. As a whole, children strongly showed collectivistic pattern and there were no sex differences in terms of cultural dispositions. The distributions of styles were in the order of HC>VI>VC>HI. The distribution of conflict resolution strategies generally were in the order of integrating and compromising>Avoiding>Dominating>Obliging for total sample and there were significant sex differences in the styles of conflict resolution strategies. This study also found that there were significant correlations between cultural dispositions and conflict resolution strategies. integrating/compromising and dominating style were different according to cultural dispositions but there were no interactive effect of sex and cultural dispositions in conflict resolution strategies. Finally, the implications of this study on theory and practice were discussed and suggestions for further study were made.

Analysis of Spatial Structure in Geographic Data with Changing Spatial Resolution (해상도 변화에 따른 공간 데이터의 구조특성 분석)

  • 구자용
    • 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.

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Improvement of Microstep Characteristics in Hydrostatic Table with Ballscrew (볼스크류로 구동되는 유정압테이블의 미소이송특성 향상)

  • 황주호;박천홍;이찬홍;이후상
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.1
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    • pp.94-100
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    • 1998
  • Microstep characteristics largely depends on the variation of friction force induced by the geometric accuracy of ballscrew, guide rail and the control characteristics of servo unit. In this paper, for improving the microstep characteristics of hydrostatic table with ballscrew, microstep resolution according to the control mode of servo amplifier and response characteristic by the variation of integral gain are tested and compared. Relationship between micro motion behavior of hydrostatic table and the output torque is also tested for acquiring the effective variables on control characteristics. From the results. it is confirmed that the torque control mode has a advantage in microstep resolution, and more stable than velocity control mode in low feed rate, and by the increase of integral gain in the elastic motion realm, response characteristics can be improved.

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RADIOMETRIC CHARACTERISTICS OF KOMPSAT-2 HIGH RESOLUTION IMAGES

  • Chi, Jun-Hwa;Yoon, Jong-Suk;Lee, Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.390-393
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    • 2007
  • KOMPSAT-2, the first Korean high resolution earth observing satellite, continuously acquires high resolution images since July 2006. The quality of satellite images should be geometrically and radiometrically ensured before distribution to users. This study focused on absolute radiometric calibration which is a prerequisite procedure to ensure the radiometric quality of optical satellite images. In this study, we performed reflectance-based vicarious calibration methods on several uniform targets collected through several field campaigns in 2007. The radiative transfer model, MODTRAN, was used to estimate the amount of energy received at the sensor. The energy reached at the sensor are affected by several factors such as reflectance of targets, atmospheric condition, geometry condition between Sun and the sensor, etc. This study proposes the absolute radiometric calibration coefficients of KOMPSAT-2 MSC images combining several types of collected data through field works and tried to compare dynamic range of sensor-detected energy with other commercial high resolution sensors.

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Multi-Temporal Spectral Analysis of Rice Fields in South Korea Using MODIS and RapidEye Satellite Imagery

  • Kim, Hyun Ok;Yeom, Jong Min
    • Journal of Astronomy and Space Sciences
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    • v.29 no.4
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    • pp.407-411
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    • 2012
  • Space-borne remote sensing is an effective and inexpensive way to identify crop fields and detect the crop condition. We examined the multi-temporal spectral characteristics of rice fields in South Korea to detect their phenological development and condition. These rice fields are compact, small-scale parcels of land. For the analysis, moderate resolution imaging spectroradiometer (MODIS) and RapidEye images acquired in 2011 were used. The annual spectral tendencies of different crop types could be detected using MODIS data because of its high temporal resolution, despite its relatively low spatial resolution. A comparison between MODIS and RapidEye showed that the spectral characteristics changed with the spatial resolution. The vegetation index (VI) derived from MODIS revealed more moderate values among different land-cover types than the index derived from RapidEye. Additionally, an analysis of various VIs using RapidEye satellite data showed that the VI adopting the red edge band reflected crop conditions better than the traditionally used normalized difference VI.

A Procedure to Select the Optimum Resolution for Satellite Imagery (위성영상의 적정 해상도 탐색 방안에 관한 연구)

  • 구자용;황철수
    • Korean Journal of Remote Sensing
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    • v.17 no.1
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    • pp.71-84
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    • 2001
  • The geographical phenomena in space are well observed in the specific scale. This scale is called the operational scale. For an analysis of the optimum scale, it is needed to measure and represent the characteristics of attribute information extracted from the satellite imagery. The development of remote sensing technique makes various images with different resolution available. Researchers can select the image with optimum resolution for their analysis among various resolutions. For an effective analysis of the scale characteristics of satellite image, we investigated the characteristics of attribute information extracted from satellite image with different resolution. The two stage-procedure for exploring the optimum resolution proposed in this study was tested by applying to the satellite imagery covering Sunchon bay. This procedure can be an effective tool utilizing the scale characteristics of attribute information extracted from satellite imagery.

An Assessment on the Hydraulic Characteristics of a Multi-dimensional Model in Response to Measurement Resolution and Spatial Interpolation Methods (지형자료의 해상도와 공간보간기법에 따른 다차원 수리모형의 유출 특성 평가)

  • Ahn, Jung-Min;Park, In-Hyeok
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.1
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    • pp.43-51
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    • 2012
  • Due to the increasing demand to utilize water fronts and water resource effectively, a multi-dimensional model that provides detailed hydraulic characteristics is required in order to improve the decision making process. An EFDC model is a kind of multi-dimension model, and it requires detailed 3D (3-dimensional) terrain in order to simulate the hydraulic characteristics of stream flow. In the case of 3D terrain creation, especially river reaches, measurement resolution and spatial interpolation methods affect the detailed 3D topography which uses input data for EFDC simulation. Such results make hydraulic characteristics to be varied. This study aims to examine EFDC simulation results depending on the 3D topographies derived by separate measurement resolution and spatial interpolation methods. The study area is at the confluence of the Nakdong and Kuemho Rivers and the event rain implemented was Typhoon Ewiniar in 2006. As a result, in the case of the area-elevation curve, the difference by means of the interpolation methods was significant when applying the same measurement resolution, except at 160m resolution. Furthermore, when the measurement resolution was 80m or above, the difference in a cross-section was occurred. Meanwhile, the water level changes between interpolation methods were insignificant by the measurement resolution except when the Kriging method was used for the 160m measurement data. Velocity changes emerged according to the interpolation methods when measurement resolution was 80m or above and the Kriging method resulted in a velocity that had a considerable gap in relation to the results from other methods at a measurement resolution of 160m.

COMPOUNDED METHOD FOR LAND COVERING CLASSIFICATION BASED ON MULTI-RESOLUTION SATELLITE DATA

  • HE WENJU;QIN HUA;SUN WEIDONG
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.116-119
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    • 2005
  • As to the synthetical estimation of land covering parameters or the compounded land covering classification for multi-resolution satellite data, former researches mainly adopted linear or nonlinear regression models to describe the regression relationship of land covering parameters caused by the degradation of spatial resolution, in order to improve the retrieval accuracy of global land covering parameters based on 1;he lower resolution satellite data. However, these methods can't authentically represent the complementary characteristics of spatial resolutions among different satellite data at arithmetic level. To resolve the problem above, a new compounded land covering classification method at arithmetic level for multi-resolution satellite data is proposed in this .paper. Firstly, on the basis of unsupervised clustering analysis of the higher resolution satellite data, the likelihood distribution scatterplot of each cover type is obtained according to multiple-to-single spatial correspondence between the higher and lower resolution satellite data in some local test regions, then Parzen window approach is adopted to derive the real likelihood functions from the scatterplots, and finally the likelihood functions are extended from the local test regions to the full covering area of the lower resolution satellite data and the global covering area of the lower resolution satellite is classified under the maximum likelihood rule. Some experimental results indicate that this proposed compounded method can improve the classification accuracy of large-scale lower resolution satellite data with the support of some local-area higher resolution satellite data.

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