Spring and summer acquired Thematic Mapper data of a spruce forest growing in southeastern Austria show the normalised differences ND1 and ND3, ratio R41, band differences BD1 and BD3, and the greenness index TMG empl...
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Spaceborne stereo-imagery can serve two major purposes: relief mapping and extraction of thematic information. Not only camera-acquired photogrammetric data of conventional and super-large format, but also hand-held p...
For existing image-guided radiation therapy systems (IGRT), the limited angular range of the cone-beam computed tomography (CBCT) scanning improves the compactness of the system and compatibility between CBCT and line...
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This paper investigates how to maintain an efficient dynamic ordered set of bit strings, which is an important problem in the field of information search and information processing. Generally, a dynamic ordered set is...
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This paper investigates how to maintain an efficient dynamic ordered set of bit strings, which is an important problem in the field of information search and information processing. Generally, a dynamic ordered set is required to support 5 essential operations including search, insertion, deletion, max-value retrieval and next-larger-value retrieval. Based on previous research fruits, we present an advanced data structure named rich binary tree (RBT), which follows both the binary-search-tree property and the digital-search-tree property. Also, every key K keeps the most significant difference bit (MSDB) between itself and the next larger value among K's ancestors, as well as that between itself and the next smaller one among its ancestors. With the new data structure, we can maintain a dynamic ordered set in O(L) time. Since computers represent objects in binary mode, our method has a big potential in application. In fact, RBT can be viewed as a general-purpose data structure for problems concerning order, such as search, sorting and maintaining a priority queue. For example, when RBT is applied in sorting, we get a linear-time algorithm with regard to the key number and its performance is far better than quick-sort. What is more powerful than quick-sort is that RBT supports constant-time dynamic insertion/deletion.
The analysis of images can take advantage of existing knowledge;this may be denoted as data-driven or knowledge-based image analysis. One example is the use of topographic maps in the study of aerial imagery. We repor...
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We present a framework and a set of techniques for the analysis and display of three-dimensional experimental data or images. We assume that the data are available in the form of two-dimensional cross sections of the ...
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We present a method to couple particle-based fluid simulation methods such as Smoothed Particle Hydrodynamics (SPH) and volume rendering in order to visualize the fluid. A volume is generated from the fluid's impl...
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In this paper we consider the limitations of Linear Discriminative Analysis (LDA) when applying it for large-scale problems. Since LDA was originally developed for two-class problems the obtained transformation is sub...
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ISBN:
(纸本)9789898111692
In this paper we consider the limitations of Linear Discriminative Analysis (LDA) when applying it for large-scale problems. Since LDA was originally developed for two-class problems the obtained transformation is sub-optimal if multiple classes are considered. In fact, the separability between the classes is reduced, which decreases the classification power. To overcome this problem several approaches including weighting strategies and mixture models were proposed. But these approaches are complex and computational expensive. Moreover, they were only tested for a small number of classes. In contrast, our approach allows to handle a huge number of classes showing excellent classification performance at low computational costs. The main idea is to split the original data into multiple sub-sets and to compute a single LDA space for each sub-set. Thus, the separability in the obtained subspaces is increased and the overall classification power is improved. Moreover, since smaller matrices have to be handled the computational complexity is reduced for both, training and classification. These benefits are demonstrated on different publicly available datasets. In particular, we consider the task of object recognition, where we can handle up to 1000 classes.
Unlike a B'ezier curve,a spline curve is hard to be obtained through geometric corner cutting on control polygons because the degree elevation operator is difficult to be obtained and geometric convergence is hard...
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Unlike a B'ezier curve,a spline curve is hard to be obtained through geometric corner cutting on control polygons because the degree elevation operator is difficult to be obtained and geometric convergence is hard to be *** order to obtain geometric construction algorithm on C-B-splines,firstly we construct the degree elevation operator by using bi-order splines in this *** we can obtain a control polygon sequence by degree elevation based on the degree elevation operator derived from a C-B-spline ***,we prove that this polygon sequence will converge to initial C-B-spline *** geometric construction algorithm possesses strong geometric *** is also simple,stable and suitable for hardware to *** algorithm is important for CAD modeling systems,since many common engineering curves such as ellipse,helix,*** be represented explicitly by C-B-splines.
We present a method to efficiently simulate fluid flows through tubular structures such as pipes and blood vessels. The method relies on the structure's centerline and for that purpose we present an algorithm to g...
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