Data assimilation and its applications

In data assimilation, one prepares the grid data as the best possible estimate of the true initial state of a considered system by merging various measurements irregularly distributed in space and time, with a prior knowledge of the state given by a numerical model. Because it may improve forecasting or modeling and increase physical understanding of considered systems, data assimilation now plays a very important role in studies of atmospheric and oceanic problems. Here, three examples are presented to illustrate the use of new types of observations and the ability of improving forecasting or modeling.

Portable 3D laser-camera calibration system with color fusion for SLAM

Nowadays, the use of RGB-D sensors have focused a lot of research in computer vision and robotics. These kinds of sensors, like Kinect, allow to obtain 3D data together with color information. However, their working range is limited to less than 10 meters, making them useless in some robotics applications, like outdoor mapping. In these environments, 3D lasers, working in ranges of 20-80 meters, are better. But 3D lasers do not usually provide color information. A simple 2D camera can be used to provide color information to the point cloud, but a calibration process between camera and laser must be done. In this paper we present a portable calibration system to calibrate any traditional camera with a 3D laser in order to assign color information to the 3D points obtained. Thus, we can use laser precision and simultaneously make use of color information. Unlike other techniques that make use of a three-dimensional body of known dimensions in the calibration process, this system is highly portable because it makes use of small catadioptrics that can be placed in a simple manner in the environment. We use our calibration system in a 3D mapping system, including Simultaneous Location and Mapping (SLAM), in order to get a 3D colored map which can be used in different tasks. We show that an additional problem arises: 2D cameras information is different when lighting conditions change. So when we merge 3D point clouds from two different views, several points in a given neighborhood could have different color information. A new method for color fusion is presented, obtaining correct colored maps. The system will be tested by applying it to 3D reconstruction.

Portable 3D laser-camera calibration system with color fusion for SLAM

Paper submitted to the 43rd International Symposium on Robotics (ISR2012), Taipei, Taiwan, Aug. 29-31, 2012.

On the decorrelation filtering of RL05 GRACE data for global applications

In autumn 2012, the new release 05 (RL05) of monthly geopotencial spherical harmonics Stokes coefficients (SC) from GRACE (Gravity Recovery and Climate Experiment) mission was published. This release reduces the noise in high degree and order SC, but they still need to be filtered. One of the most common filtering processing is the combination of decorrelation and Gaussian filters. Both of them are parameters dependent and must be tuned by the users. Previous studies have analyzed the parameters choice for the RL05 GRACE data for oceanic applications, and for RL04 data for global application. This study updates the latter for RL05 data extending the statistics analysis. The choice of the parameters of the decorrelation filter has been optimized to: (1) balance the noise reduction and the geophysical signal attenuation produced by the filtering process; (2) minimize the differences between GRACE and model-based data; (3) maximize the ratio of variability between continents and oceans. The Gaussian filter has been optimized following the latter criteria. Besides, an anisotropic filter, the fan filter, has been analyzed as an alternative to the Gauss filter, producing better statistics.

Development of techniques and data for evaluating ride quality. Volume III: guidelines for development of ride quality models and their applications. Final report.

Transportation Department, Research and Special Programs Directorate, Washington, D.C.

Networking and other forms of cooperation : papers presented at the 1973 Clinic on Library Applications of Data Processing, April 29-May 2, 1973 /

Title on spine: Library applications of data processing, 1973.

Papers presented at the ... Clinic on Library Applications of Data Processing, ...

Title from half-title page.

The use of computers in literature searching and related reference activities in libraries : papers presented at the 1975 Clinic on Library Applications of Data Processing, April 27-30, 1975 /

Includes bibliographical references.

The economics of library automation : [papers presented at the 1976 Clinic on Library Applications of Data Processing, April 25-28, 1976] /

Spine title: Library applications of data processing: 1976.

MARC uses and users : papers presented at the 1970 Clinic on Library Applications of Data Processing conducted by the University of Illinois Graduate School of Library Science, April 26-29, 1970 /

Includes bibliographical references and index.

Applications of minicomputers to library and related problems : papers presented at the 1974 Clinic on Library Applications of Data Processing, April 28-May 1, 1974 /

Title on spine: Library applications of data processing.

Applications of on-line computers to library problems : papers presented at the 1972 Clinic on Library Applications of Data Processing, April 30-May 3, 1972 /

Title on spine: Library applications of data processing: 1972.

What is user friendly? : Clinic on Library Applications of Data Processing, 1986 /

Includes bibliographies and index.

Demonstration of photovoltaic power source in remote applications : lighting, weather data gathering and public demonstration systems : Wildlife Prairie Park, Peoria, Illinois.

"Printed: May 1990."