Ministry of Economy, Trade and Industry (METI) of Japan is developing the hyperspectral sensor that is planned to be installed in the next generation earth observation satellite. Hyperspectral sensor is able to collect information as a set of images in high spectral resolution. It has begun to spread into fields of agriculture and environmental surveillance in Japan. The aim of this study is to study the estimation formula of rice grain protein contents using hyperspectral data. Especially, it aimed to standardize the estimation formula for the same observation area and the same rice species. We investigated the standardized estimation formula of rice grain protein contents as paddy growing information through two approaches. One is to use the vegetation indices as biophysical indicator in previous research. Another one is to use Normalized Difference Spectral Index (NDSI). For the estimation rice grain protein contents in Osaki city, Miyagi prefecture, the standardized estimation formula in year of 2007, 2008, and 2009 was obtained. Obtained formula uses ratio of R460 and R510 as independent variable and coefficient of determination R2 is 0.72.
Error budget analysis and sensitivity analysis of the method for aerosol refractive index and size distribution estimation with ground based polarization measurement data for vicarious calibration of solar reflection channels of mission instruments onboard satellites are performed. The proposed method uses a relation between aerosol refractive index and p and s polarized downwelling solar diffuse irradiance. It is much easy to measure p and s polarized irradiance on the ground with a portable measuring instrument rather than solar direct, diffuse and aureole measurements. Through theoretical and simulation studies, it is found that the proposed method shows an acceptable estimation accuracy of refractive index and size distribution using measured downwelling p and s polarized irradiance data with a measuring instrument. It found that Degree of Polarization : DP is most sensitive to imaginary part refractive index followed by real part of refractive index, aerosol optical depth, surface reflectance and Junge parameter. It is also found that 5% of error of DP measurement is acceptable for less than 3% of estimation accuracy of aerosol refractive index and size distribution. The instrument is pointing to the several directions from the center of perpendicular to the sun in the principal plane. Field experimental results also show a validity of the proposed method in comparison to the estimated results from the conventional method with solar direct, diffuse and aureole measurement data.
Nowadays, high resolution satellite imageries can be used in various fields. The imageries are expected to measure precise coordinates. Then accurate geometric model is required to calculate image coordinates (u, v) from ground coordinates (x, y, z). Generally, RPC model is applied as the accurate geometric model. However, the RPC model has a systematic error with several pixels. To correct the RPC model, information of GCP (Ground Control Points) should be used. GCP are consisted with precise ground coordinates and corresponded image coordinates. An accuracy of ground coordinates is required less than 1/5 of ground sampling distance of satellite imagery. GCP database in Shikoku Japan has been established by authors. Over 550 points were finished to survey within 4cm accuracy by GPS VRS observation. However, point based GCP doesn't have enough accuracy for high resolution satellite imageries. Because, image coordinates are selected by visual interpretation. Poly-lines or polygon type GCP should be prepared to select accurate image coordinates by image processing. In this study, Poly-line type GCP were suggested. Target satellite imageries are ALOS PRISM which are panchromatic imageries with 2.5m ground sampling distance. In the test area, 5 intersections and 4 curves of road were surveyed, and Poly-line type GCP were prepared. Corresponding coordinates of Poly-line type GCP in PRISM imageries can be computed by image matching process. Least squares matching method was applied in this study. Then, precise image coordinates can be obtained. Poly-line type GCP were validated using bias corrected RPC model. The root mean square error showed 0.5 pixel. On the other hand, point based GCP were also validated. In the case of point based GCP, corresponding coordinates were selected by visual interpretation. The root mean square error showed around 1.0 pixel. The results showed poly-line type GCP were effective for precise image registration.
The goal of this study is to use NDVI and LST (land surface temperature) time series NOAA/AVHRR data to estimate global tendencies in land cover changes from 1982 to 1999. As a preprocessing step, Temporal Window Operation-correction (TWO Method) was performed to reduce the effects of clouds. The mean (AVG_NDVI and AVG_LST) and standard deviation (STD_NDVI and STD_LST) values were calculated for each NDVI and LST data over the 18 period. The results showed that NDVI varied according to rate of vegetation coverage ; and LST varied by latitude, altitude and whether or not the area was vegetated. In order to identify any abnormal trends, AVG_NDVI and STD_NDVI were used to calculate the monthly deviation. These calculations revealed that Africa suffered a period of drought from July 1984 to January 1985. In addition, in order to reveal changes in land cover by season, profile matching, taking into consideration phonological shifts, was implemented, and the difference between these results and average (DIF_NDVI and DIF_LST) values were determined. The results of these comparisons allowed identification of regional changes in NDVI under the influence of abnormal weather patterns. Furthermore, the gradient was extracted for 18 years of NDVI and LST data, using the linear regression analysis from DIF_NDVI and DIF_LST. The two gradient values plotted for NDVI and LST gradient indicated several important trends, such as an increase in NDVI in many grassland areas, including farmland ; and a increase in LST in desert areas.
Zoom lenses are widely accepted in vision system. However, the use of zoom lenses is not general in close range photogrammetry from the view point of instability by zooming. With the spread of consumer grade digital cameras with integrated zoom lenses, in particular high zooming lens such as 35× were appeared on the market in Japan. In these circumstances, digital photogrammetry using the consumer grade digital cameras is enormously expected in various application fields. There is a large body of literature on the calibration of zoom lenses. However, there is still problem for effective digital photogrammetry using the consumer grade digital cameras. The problem is practical calibration technique of zoom lens. In this paper, a newly calibration technique is proposed based on correction of zoom lens misalignment. In order to evaluate the newly calibration technique of zoom lens, calibration tests were conducted using 5 kinds of consumer grade digital camera (3-5×), 3 kinds of high zooming consumer grade digital camera (12-30×) and digital SLR camera with zoom lens (11×). The results show that the newly calibration technique is simple and stable for all zoom setting.
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