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Estimating ground-level PM2.5 in Texas from remote sensing satellite data with interpolation and regression methodsJiang, Xiaoyan 2009 August 1900 (has links)
The integration of remote sensing satellite data in air quality monitoring system at a regional scale is an important method to provide high spatial / temporal resolution information. This work focuses on estimating high spatial / temporal resolution ground-level information about particulate matter with aerodynamic diameters less than 2.5 um (PM2.5), with the utilization of MODIS aerosol optical thickness (AOT) data and meteorological data. Several missing data reconstruction techniques including Bayesian inversion, regularization and prediction-error filter are employed to estimate PM2.5 from satellite data. The results show that several direct missing data interpolation methods have the capability to estimate some distinctive features on the basis of available ground-based measurements, while the PEF method tends to generate more information with the aid of satellite AOT information.
In addition to interpolation methods, general linear regression methods are used to predict ground-level PM2.5 with the consideration of other factors that have been shown to play an important role in predictions. Ordinary Least Square (OLS) method, when natural log taken on dependent and independent variables, is able to reduce the violation of homoscedasticity. The scatterplot of predicted and measured PM2.5 shows a strong correlation over the validation region, indicating the ability of the regression model to predict PM2.5. Weighted Least Square (WLS) method also has advantage in improving homoscedasticity. The predicted and measured PM2.5 has a relatively high correlation. / text
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On extension of the generalized sampling theorem /Jerri, Abdul J., January 1967 (has links)
Thesis (Ph. D.)--Oregon State University, 1967. / Typescript (photocopy). Includes bibliographical references (p. 89-93). Also available on the World Wide Web.
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Adaptive bilateral extensor for image interpolationRiehle, Thomas J. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 23, 2007) Includes bibliographical references.
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A ROM-less DDFS Using A Parabolic Polynomial Interpoltion Method with An Offset Adjustment and Fabrication of Silcon-based OEIC Comprising Photodetector and Transimpedance AmplifierLee, Chia-Chuan 14 July 2008 (has links)
This thesis includes two topics. The first topic is a ROM-less DDFS (Direct Digital Frequency Synthesizer) using a parabolic polynomial in-terpolation method with an offset adjustment. The second one is the de-sign and fabrication of a silicon-based OEIC(optoelectronic integrated circuit) comprising photodetectors and transimpedance amplifiers.
The ROM-less DDFS employs a parabolic polynomial interpola?tion method with an offset adjustment, where an initial phase offset is added into parabolic polynomials. Besides, the pipelining architecture is adopted to improve the speed of the proposed DDFS.
The OEIC uses the hybrid integration technique to integrate the III-V optoelectronic devices (photodetector) and CMOS integrated circuits (transimpedance amplifier) onto the same substrate (silicon substrate) by the wafer bounding technique. With the realization of the hybrid in-tegration, the bandwidth degeneration resulted from the traditional wire bounding can be avoided.
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Verification of a Western Pacific Circulation Model Using Global Drifter DataYu, Sing-ru 29 August 2008 (has links)
The marine currents around the Pacific Northwest are researched by lots of scholars. The methods of the on-site observation, such as the shipping measurements and data buoys, were applied by researcher in the past. However, it is difficult to get comprehensive information on space by early methods, and it is often limited by the manpower and funding. With computer technology advances, numerical models get improving the accuracy and resolution. Therefore, development of the numerical models also becomes one of the methods to understand the ocean.
There are many current models and large databases which are developed. However, few studies combine the two. Therefore, this study adopts the simulated results of POLCOMS (Proudman Oceanographic Laboratory Coastal-Ocean Modeling System) in 2002 near the northwest Pacific (9.9¢X N ~ 41.9¢X N, 104.9¢X E ~ 139.9¢X E) to analyze some situations. The result can be compared with the measured data, and test the model.
In order to evaluate the accuracy of the results of the model, the simulated tracks can be calculated by the result of the model and the initial location of the measured data. However, the resolutions of time and space are only one day and 7.5 degree. Hence, the methods of linear interpolation and bilinear interpolation are applied to interpolate the model result in the time dimension and space dimension. By using the latitude and longitude of the initial points, the azimuth, and the geographic distance, the simulated tracks can be calculated. Therefore, the results of POLCOMS can be confirmed by global drifter data from NOAA/AOML.
According to the results of evaluating, the simulation trends of the seasons are similar to measured data. It can prove that this model has a certain degree of accuracy. However, simulation and the measured data can not be completely similar when abnormal weather phenomenon occurs. It is because the model was driven by the average wind field. There are suggestions to make the model complete by adding the weather information during the periods of the typhoons. Besides, the model can simulate the temperature and salinity of the ocean. Increasing the comparison of them will make the model integrated in the future, and obtain more correct information of the flow fields around the Pacific Northwest.
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Caractérisation de SER Basse Fréquence et Modes CaractéristiquesCognault, Aurore Magoulès, Frédéric. January 2009 (has links)
Thèse de doctorat : mathématiques appliquées aux systèmes : Ecole centrale de Paris : 2009. / Titre provenant de l'écran-titre. Bibliogr. 45 réf.
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Video interpolation for deinterlacing and frame rate up conversion /Tu, Shing Fat. January 2009 (has links)
Includes bibliographical references (p. 73-75).
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An evaluation of the accuracy of readability of two dials suitable for system outputStewart, Sinclair Bingham, 1940- January 1967 (has links)
No description available.
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An investigation of sampled data interpolation errorKnight, Joseph Alexander 08 1900 (has links)
No description available.
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The synthesis of estuarine bathymetry from sparse sounding dataBurroughes, Janet Eirlys January 2001 (has links)
The two aims of the project involved: 1. Devising a system for prediction o f areas of bathymetric change within the Fal estuary 2. Formulating and evaluating a method for interpolating single beam acoustic bathymetry to avoid artefacts o f interpolation. In order to address these aims, sources of bathymetric data for the Fal estuary were identified as Truro Harbour Office, Cornwall County Council and the Environment Agency. The data collected from these sources included red wavelength Lidar, aerial photography and single beam acoustic bathymetry from a number of different years. These data were input into a Geographic Information System (GIS) and assessed for suitability for the purposes o f data comparison and hence assessment of temporal trends in bathymetry within the estuary Problems encountered during mterpolation of the acoustic bathymetry resulted in the later aim of the project, to formulate an interpolation system suitable for interpolation of the single beam, bathymetric data in a realistic way, avoiding serious artefacts of interpolation. This aim was met, successfully, through the following processes: 1. An interpolation system was developed, using polygonal zones, bounded by channels and coastlines, to prevent interpolation across these boundaries. This system, based on Inverse Distance Weighting (IDW) interpolation, was referred to as Zoned Inverse Distance Weighting (ZIDW). 2. ZIDW was found, by visual inspection, to eliminate the interpolation artefacts described above. 3. The processes of identification of sounding lines and charmels, and the allocation of soundings and output grid cells to polygons, were successfully automated to allow ZIDW to be applied to large and multiple data sets. Manual intervention was maintained for processes performed most successfully by the human brain to optimise the results o f ZIDW. 4. To formalise the theory of ZIDW it was applied to a range of idealised, mathematically defined chaimels. For simple straight and regular curved, mathematical channels interpolation by the standard TIN method was found to perform as well as ZIDW. 5. Investigation of sinusoidal channels within a rectangular estuary, however, revealed that the TIN method begins to produce serious interpolation artefacts where sounding lines are not parallel to the centre lines o f channels and ridges. Hence, overall ZIDW was determined mathematically to represent the optimum method o f interpolation for single beam, bathymelric data. 6. Finally, ZIDW was refined, using data from the Humber and Gironde estuaries, to achieve universal applicability for interpolation of single beam, echo soimding data from any estuary. 7. The refinements involved allowance for non-continuous, flood and ebb type charmels; consideration of the effects of the scale of the estuary; smoothing of the channels using cubic splines; interpolation using a 'smart' ellipse and the option to reconstruct sounding lines from data that had previously been re-ordered.
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