This paper presents a new data structure, Slice-based Binary Shell (SBS), for efficient manipulation and rendering of binary volume data. Since SBS stores only surface voxels with selected attributes ...of the voxels in a slice-based data structure that allows direct access to the voxels, it shows high storage and computational efficiency. This efficiency becomes more prominent when representing multiple binary objects. We also present an efficient rendering algorithm for SBS. The algorithm, based on the shear-warp technique, provides high-speed interactive rendering for binary volumes of many objects on a PC with no specialized hardware.
G-tree, combining the features of both grids and B-trees, is a disk-based spatial data structure for organizing multidimensional data. This paper presents an efficient access method for retrieving ...similar pictures from iconic databases using G-tree. The proposed method preserves the merits of G-tree, and hence indexing the pictures in the database, processing range queries for similarity retrieval, inserting/deleting a picture into/from the database, and effective memory utilization can be achieved in practical applications. In order to improve the acceptability of similarity retrieval as compared to previous works, we define a similarity function by the usage of query ranges, and each range corresponds to one object in the query. This similarity function reflects both the direction and the distance knowledge among objects in the pictures. Besides, the result of similarity retrieval can be further refined by simply adjusting the query ranges or increasing the threshold value of the predefined similarity function.
The extensive amount of spatial databases accumulated from various computed technology requires automated data mining tools to discover hidden and novel information from large and complex databases. ...In other words, the major concern is high dimensionality and complexity of spatial data which has created serious concerns among the researchers to retrieve effective and efficient clusters from large and complex spatial features. In this paper we have proposed a spatial clustering algorithm (SPAS) and Knowledge driven framework to discover clusters of variant shapes and size with domain specific knowledge. The application of our proposed algorithm is tested on real world spatial medical databases collected from SEER datasets which has record of Lung cancer patients from the year 1975 - 2008. The case includes information on patient's gender, ZIP code of a patient's residence, year of diagnosis, primary site, stage at diagnosis, and age group. Each record represents a diagnosed cancer case assigned to the patient's residence at time of diagnosis. The objective of study was to discover effective and efficient spatial clusters with domain specific knowledge for futuristic decision making.
Traditionally most camera-based position estimation systems use only a few points to calibrate cameras. In this paper, we investigate a novel and alternate approach for 3D position estimation by ...using a larger number of points arranged in a 3D grid. We present an implementation of the active-space indexing mechanism which uses three cameras. Given the corresponding points in camera images, a precise estimation of the position can be obtained. The active-space indexing method can be also used as a spatial filter to eliminate the large number of possible corresponding pairs from consideration. This capability, unique only to the active-space indexing method, provides a tractable algorithm to the otherwise intractable situation.
The spatial data structure known as bincode is a simple and storage–saving encoding scheme for representing binary images. In this paper, we first present eight efficient operations for mirroring and ...rotating bincode–based images. Among the operations, certain special operations on individual bits within bincodes are needed. Then we present a newly proposed logical representation for implementing the bitwise operations in the operations. Finally, we implement the bitwise operations in hardware to speed up the special manipulations.
Cloud computing system comprises of a set of cloud nodes scattered over a large geographical surface. These cloud nodes usually helps to handle efficiently a new arrived job in cloud system. Now a ...day's researchers used to work for logically partitioning the earth surface such that every partition contains at least one cloud node which will be prime dedicated for handling jobs arrived in that partition. This phenomenon of partitioning the cloud system is called as `Cloud Division Rule'. Using spatial data structure we have recursively broken down the earth surface in small zone, namely cloud cluster, containing single cloud node. For getting nodes' information (like load status, network bandwidth etc.) from the master cloud node traversing all the child cloud node is one of the way. Traversal of each cloud node is recursively performed in order to provide some services to users' request in considered cloud system. As millions of cloud nodes over the earth surface are to be clustered and recursively traversed, so a huge number of stack space and stack operations are internally initiated. To optimize these operations we have constructed a threaded k-d tree and do non-recursive inorder traversal over it. This novel approach makes the searching of ancestor and descendant cloud nodes from the current cloud node very easy and also optimizes the computation time and internal memory space of the computation unit which is one of the prime aspect for today's cloud computing Infrastructure as a Service (IaaS).
Concerns about the protection of the global transport network have risen the need of new security and surveillance systems. Ontology-based and fusion systems represent an attractive alternative for ...practical applications focused on fast and accurate responses. This paper presents an architecture based on a geometric model to efficiently predict and calculate the topological relationships between spatial objects. This model aims to reduce the number of calculations by relying on a spatial data structure. The goal is the detection of threatening behaviors next to points of interest without a noticeable loss of efficiency. The architecture has been embedded in an ontology-based prototype compliant with the Joint Directors of Laboratories (JDL) model for Information Fusion. The prototype capabilities are illustrated by applying international protection rules in maritime scenarios.
The Fractal Nature of Geographic Phenomena Goodchild, Michael F.; Mark, David M.
Annals of the Association of American Geographers,
June 1987, Letnik:
77, Številka:
2
Journal Article
Recenzirano
Fractal concepts have attracted substantial popular attention in the past few years. The key ideas originated in studies of map data, and many of the applications continue to be concerned with ...spatial phenomena. We review the relevance of fractals to geography under three headings; the response of measure to scale, self-similarity, and the recursive subdivision of space. A fractional dimension provides a means of characterizing the effects of cartographic generalization and of predicting the behavior of estimates derived from data that are subject to spatial sampling. The self-similarity property of fractal surfaces makes them useful as initial or null hypothesis landscapes in the study of geomorphic processes. A wide variety of spatial phenomena have been shown to be statistically self-similar over many scales, suggesting the importance of scale-independence as a geographic norm. In the third area, recursive subdivision is shown to lead to novel and efficient ways of representing spatial data in digital form and to be a property of familiar models of spatial organization. We conclude that fractals should be regarded as a significant change in conventional ways of thinking about spatial forms and as providing new and important norms and standards of spatial phenomena rather than empirically verifiable models.
We first propose a modified S-tree. Let the memory required in the modified S-tree be O(
m), then our derived fast search algorithm can be performed in O(
t) time,
t ⩽ m. Our algorithm is quite ...competitive with the algorithm of
Jonge, Scheuermann, and Schijf (1994). The application to pictorial database is also addressed.
Linear Quadtree Construction in Real Time 黃其彥(CHI-YEN HUANG); 陳育威(YU-WEI CHEN)
Journal of Information Science and Engineering,
09/2010, Letnik:
26, Številka:
5
Journal Article
The paper presents a novel method for encoding the linear quadtree of a given image. In this method, the pixels of the image are scanned in row major order. In each encountered pixel, the result ...codes in the linear quadtree are updated simultaneously in real time. The linear quadtree is thus obtained after all pixels are processed. This method is quite different from those in previous studies, which need huge memory space to store the input pixels for further processing, or need post processing to rearrange the sequence of the final codes to put them back in increasing order. Moreover, since this method adopts simpler and more efficient operations than previous methods, it is found to be faster in experiments.
