• Title/Summary/Keyword: Spectral Adjustment

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Adjustment of Spectral Information of Different Facets in a Surface Material using Image Segmentation

  • Lee Jong Yeol
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.609-612
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    • 2004
  • Geometric shape in a surface material sometimes produces different slopes that have different illuminations. It causes some difficulties to get same classification results or to identify as an object for the different facets in a surface material. A regression method is suggested to adjust the spectral information of different facets in a surface material using image segments. The method to adjust spectral information in a building facets was very successful. The most important advantage of this method is to keep the intensity of spectral information as well as spectral response. This method can also be implemented in an adaptive way.

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Reduction of Spectral Distortion in PAN-sharpening Using Spectral Adjustment and Anisotropic Diffusion (분광 조정과 비등방성 확산에 의한 PAN-Sharpened 영상의 분광 왜곡 완화)

  • Lee, Sanghoon
    • Korean Journal of Remote Sensing
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    • v.31 no.6
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    • pp.571-582
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    • 2015
  • This paper proposes a scheme to reduce spectral distortion in PAN-sharpening which produces a MultiSpectral image (MS) with the higher resolution of PANchromatic image (PAN). The spectral distortion results from reconstructing spatial details of PAN image in the MS image. The proposed method employs Spectral Adjustment and Anisotropic Diffusion to make a reduction of the distortion. The spectral adjustment makes the PAN-sharpened image agree with the original MS image, but causes block distortion because the spectral response of a pixel in the lower resolution is assumed to be equal to the average response of the pixels belonging to the corresponding area in the higher resolution at a same wavelength. The block distortion is corrected by the anisotropic diffusion which uses a conduct coefficient estimating from a local computation of PAN image. It results in yielding a PAN-sharpened image with the spatial structure of PAN image. GSA is one of PAN-sharpening techniques which are efficient in computation as well as good in quantitative quality evaluation. This study suggests the GSA as a preliminary PAN-sharpening method. Two data sets were used in the experiment to evaluate the proposed scheme. One is a Dubaisat-2 image of $1024{\times}1024$ observed at Los Angeles area, USA on February, 2014, the other is an IKONOS of $2048{\times}2048$ observed at Anyang, Korea on March, 2002. The experimental results show that the proposed scheme yields the PAN-sharpened images which have much less spectral distortion and better quantitative quality evaluation.

Capacity Improvement of Dual-Polarized Antenna Systems in Non-Line-of-Sight Channels (비가시선 채널에서 이중 편파 안테나 시스템의 용량 증대)

  • Shin, Changyong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.7
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    • pp.4918-4924
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    • 2015
  • In this paper, we consider the capacity improvement of systems exploiting dual-polarized antennas for two-user transmission. To this end, we analyze the upper bounds of ergodic capacities for multicast and unicast data services in the systems, and propose the condition for adjusting the complex cross-polarization discriminations (XPDs) to maximize the ergodic capacities. In addition, we present the adjustment condition of the complex XPDs that can achieve spectral efficiencies close to the maximum ergodic capacities with lower system complexity. Lastly simulation results demonstrate that the systems using the proposed conditions can obtain higher spectral efficiencies than the ones employing different adjustment conditions including the exiting adjustment condition.

IKONOS Image Fusion Using a Fast Intensity-Hue-Saturation Fusion Technique (빠른 IHS 기법을 이용한 IKONOS 영상융합)

  • Yun, Kong-Hyun
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.1 s.35
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    • pp.21-27
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    • 2006
  • Among various image fusion methods, intensity-hue-saturation(IHS) technique is capable of quickly merging the massive volumes of data. For IKONOS imagery, IHS can yield satisfactory 'spatial' enhancement but may introduce 'spectral' distortion, appearing as a change in colors between compositions of resampled and fused multispectral bands. To solve this problem a fast IHS fusion technique with spectral adjustment is presented. The experimental results demonstrate that the proposed approach can provide better performance than the conventional IHS method, in both processing speed and image quality.

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Absolute Radiometric Calibration for KOMPSAT-3 AEISS and Cross Calibration Using Landsat-8 OLI

  • Ahn, Hoyong;Shin, Dongyoon;Lee, Sungu;Choi, Chuluong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.4
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    • pp.291-302
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    • 2017
  • Radiometric calibration is a prerequisite to quantitative remote sensing, and its accuracy has a direct impact on the reliability and accuracy of the quantitative application of remotely sensed data. This paper presents absolute radiometric calibration of the KOMPSAT-3 (KOrea Multi Purpose SATellite-3) and cross calibration using the Landsat-8 OLI (Operational Land Imager). Absolute radiometric calibration was performed using a reflectance-based method. Correlations between TOA (Top Of Atmosphere) radiances and the spectral band responses of the KOMPSAT-3 sensors in Goheung, South Korea, were significant for multispectral bands. A cross calibration method based on the Landsat-8 OLI was also used to assess the two sensors using near simultaneous image pairs over the Libya-4 PICS (Pseudo Invariant Calibration Sites). The spectral profile of the target was obtained from EO-1 (Earth Observing-1) Hyperion data over the Libya-4 PICS to derive the SBAF (Spectral Band Adjustment Factor). The results revealed that the TOA radiance of the KOMPSAT-3 agree with Landsat-8 within 5.14% for all bands after applying the SBAF. The radiometric coefficient presented here appears to be a good standard for maintaining the optical quality of the KOMPSAT-3.

Feasibility Assessment of Spectral Band Adjustment Factor of KOMPSAT-3 for Agriculture Remote Sensing (농업관측을 위한 KOMPSAT-3 위성의 Spectral Band Adjustment Factor 적용성 평가)

  • Ahn, Ho-yong;Kim, Kye-young;Lee, Kyung-do;Park, Chan-won;So, Kyu-ho;Na, Sang-il
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1369-1382
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    • 2018
  • As the number of multispectral satellites increases, it is expected that it will be possible to acquire and use images for periodically. However, there is a problem of data discrepancy due to different overpass time, period and spatial resolution. In particular, the difference in band bandwidths became different reflectance even for images taken at the same time and affect uncertainty in the analysis of vegetation activity such as vegetation index. The purpose of this study is to estimate the band adjustment factor according to the difference of bandwidth with other multispectral satellites for the application of KOMPSAT-3 satellite in agriculture field. The Spectral band adjustment factor (SBAF) were calculated using the hyperspectral satellite images acquired in the desert area. As a result of applying SBAF to the main crop area, the vegetation index showed a high agreement rate of relative percentage difference within 3% except for the Hapcheon area where the zenith angle was 25. For the estimation of SBAF, this study used only one set of images, which did not consider season and solar zenith angle of SBAF variation. Therefore, long-term analysis is necessary to solve SBAF uncertainty in the future.

Noisy Speech Recognition Based on Spectral Mapping Techniques (스펙트럼사상기법을 기초로 한 잡음음성인식)

  • Lee, Ki-Young
    • The Journal of the Acoustical Society of Korea
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    • v.14 no.1E
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    • pp.39-45
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    • 1995
  • This paper presents noisy speech recognition method based on spectral mapping techniques of speaker adaptation method. In the presented method, the spectral mapping training makes the spectral distortion of noisy speech reduced, and for the more correctively spectral mapping, let the adjustment window;s slope be adaptive to several word lengths. As a result of recognition experiment, the recognition rate is higher than that of the conventional method using VQ and DTW without noise processing. Even when SNR level is 0 dB, the recognition rate is 10 times more than that using the conventional method. It is confirmed that the speacker adaptation technique using the spectral mapping training has an ability to improve the recognition performance for noisy speech.

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Smooth Tests for Seasonality (평활 계절성 검정)

  • Lee, Geung-Hee
    • The Korean Journal of Applied Statistics
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    • v.24 no.1
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    • pp.45-59
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    • 2011
  • When using X-12-ARIMA for seasonal adjustment, we usually check whether the series has stable seasonality or not via D8 F-tests, Kruskal-Wallis test, and the spectral diagnostics. In this paper, we develop several smooth tests for seasonality based on a Fourier series to improve the spectral diagnostics of X-12-ARIMA. A simulation study is conducted to compare five smooth tests for seasonality and X-12-ARIMA's D8 F-test an Kruskal-Wallis test. The simulation study shows that smooth tests for seasonality performed well compared with D8 F-tests and a Kruskal-Wallis test.

Effect of pH Adjustment during Production of Egg White Powder on Foaming and Gelling Properties

  • Kim, Jeong-Yeon;Kim, Mi-Ra; Park, Ki-Hwan;Shim, Jae-Yong;Imm, Jee-Young
    • Food Science and Biotechnology
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    • v.15 no.3
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    • pp.418-423
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    • 2006
  • Egg white powders (EWPs) were produced after pH adjustment (PH 6-9) of fresh egg white, followed by spray-drying, and foaming and gelling properties of EWPs were examined. EWP produced after pH adjustment to 6.5 (EWP-6.5) resulted in significantly higher foaming ability and gel hardness than control and other pH-adjusted EWP. Significant increases in surface -SH content and surface hydrophobicity of EWP-6.5 coincided with improved foaming ability and gel hardness. Significantly higher consistency index for reconstituted EWP-6.5 indicates unfolding of egg white protein was substantially increased in EWP-6.5. Decreased a-helix content in EWP-6.5 was confirmed by circular dichroism spectral analysis. These results indicate pH adjustment prior to spray-drying leads to structural changes in egg white proteins, significantly affecting major functionalities of EWP.

Bootstrap methods for long-memory processes: a review

  • Kim, Young Min;Kim, Yongku
    • Communications for Statistical Applications and Methods
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    • v.24 no.1
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    • pp.1-13
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    • 2017
  • This manuscript summarized advances in bootstrap methods for long-range dependent time series data. The stationary linear long-memory process is briefly described, which is a target process for bootstrap methodologies on time-domain and frequency-domain in this review. We illustrate time-domain bootstrap under long-range dependence, moving or non-overlapping block bootstraps, and the autoregressive-sieve bootstrap. In particular, block bootstrap methodologies need an adjustment factor for the distribution estimation of the sample mean in contrast to applications to weak dependent time processes. However, the autoregressive-sieve bootstrap does not need any other modification for application to long-memory. The frequency domain bootstrap for Whittle estimation is provided using parametric spectral density estimates because there is no current nonparametric spectral density estimation method using a kernel function for the linear long-range dependent time process.