107,188 research outputs found
Multi-dimensional modelling for the national mapping agency: a discussion of initial ideas, considerations, and challenges
The Ordnance Survey, the National Mapping Agency (NMA) for Great Britain, has recently
begun to research the possible extension of its 2-dimensional geographic information into a
multi-dimensional environment. Such a move creates a number of data creation and storage
issues which the NMA must consider. Many of these issues are highly relevant to all NMA’s
and their customers alike, and are presented and explored here.
This paper offers a discussion of initial considerations which NMA’s face in the creation of
multi-dimensional datasets. Such issues include assessing which objects should be mapped in
3 dimensions by a National Mapping Agency, what should be sensibly represented
dynamically, and whether resolution of multi-dimensional models should change over space.
This paper also offers some preliminary suggestions for the optimal creation method for any
future enhanced national height model for the Ordnance Survey. This discussion includes
examples of problem areas and issues in both the extraction of 3-D data and in the
topological reconstruction of such. 3-D feature extraction is not a new problem. However, the
degree of automation which may be achieved and the suitability of current techniques for
NMA’s remains a largely unchartered research area, which this research aims to tackle.
The issues presented in this paper require immediate research, and if solved adequately
would mark a cartographic paradigm shift in the communication of geographic information –
and could signify the beginning of the way in which NMA’s both present and interact with
their customers in the future
Image mining: trends and developments
[Abstract]: Advances in image acquisition and storage technology have led to tremendous growth in very large and detailed image databases. These images, if analyzed, can reveal useful information to the human users. Image mining deals with the extraction of implicit knowledge, image data relationship, or other patterns not explicitly stored in the images. Image mining is more than just an extension of data mining to image domain. It is an interdisciplinary endeavor that draws upon expertise in computer vision, image processing, image retrieval, data mining, machine learning, database, and artificial intelligence. In this paper, we will examine the research issues in image mining, current developments in image mining, particularly, image mining frameworks, state-of-the-art techniques and systems. We will also identify some future research directions for image mining
Platonic model of mind as an approximation to neurodynamics
Hierarchy of approximations involved in simplification of microscopic theories, from sub-cellural to the whole brain level, is presented. A new approximation to neural dynamics is described, leading to a Platonic-like model of mind based on psychological spaces. Objects and events in these spaces correspond to quasi-stable states of brain dynamics and may be interpreted from psychological point of view. Platonic model bridges the gap between neurosciences and psychological sciences. Static and dynamic versions of this model are outlined and Feature Space Mapping, a neurofuzzy realization of the static version of Platonic model, described. Categorization experiments with human subjects are analyzed from the neurodynamical and Platonic model points of view
Moving-edge detection via heat flow analogy
In this paper, a new and automatic moving-edge detection algorithm is proposed, based on using the heat flow analogy. This algorithm starts with anisotropic heat diffusion in the spatial domain, to remove noise and sharpen region boundaries for the purpose of obtaining high quality edge data. Then, isotropic and linear heat diffusion is applied in the temporal domain to calculate the total amount of heat flow. The moving-edges are represented as the total amount of heat flow out from the reference frame. The overall process is completed by non-maxima suppression and hysteresis thresholding to obtain binary moving edges. Evaluation, on a variety of data, indicates that this approach can handle noise in the temporal domain because of the averaging inherent of isotropic heat flow. Results also show that this technique can detect moving-edges in image sequences, without background image subtraction
Hyperspectral colon tissue cell classification
A novel algorithm to discriminate between normal and malignant tissue cells of the human colon is presented. The microscopic level images of human colon tissue cells were acquired using hyperspectral imaging technology at contiguous wavelength intervals of visible light. While hyperspectral imagery data provides a wealth of information, its large size normally means high computational processing complexity. Several methods exist to avoid the so-called curse of dimensionality and hence reduce the computational complexity. In this study, we experimented with Principal Component Analysis (PCA) and two modifications of Independent Component Analysis (ICA). In the first stage of the algorithm, the extracted components are used to separate four constituent parts of the colon tissue: nuclei, cytoplasm, lamina propria, and lumen. The segmentation is performed in an unsupervised fashion using the nearest centroid clustering algorithm. The segmented image is further used, in the second stage of the classification algorithm, to exploit the spatial relationship between the labeled constituent parts. Experimental results using supervised Support Vector Machines (SVM) classification based on multiscale morphological features reveal the discrimination between normal and malignant tissue cells with a reasonable degree of accuracy
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