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A BALANCED HIERARCHICAL data STRUCTURE FOR MULTIDIMENSIONAL data WITH HIGHLY EFFICIENT DYNAMIC CHARACTERISTICS

IEEE TRANSACTIONS ON KNOWLEDGE AND data ENGINEERING 1993年第4期5卷 682-694页

作者： NAKAMURA, Y ABE, S OHSAWA, Y SAKAUCHI, M SAITAMA UNIV FAC ENGNURAWASAITAMA 338JAPAN UNIV TOKYO INST IND SCIMINATO KUTOKYO 106JAPAN

A new multidimensional data structure, multidimensional tree (MD-tree), is proposed. The MD-tree is developed by extending the concept of the B-tree to the multidimensional data, so that the MD-tree is a height balanced tree similar to the B-tree. The theoretical worst-case storage utilization is guaranteed to hold more than 66.7%(2/3) of full capacity. In this paper, the structure of the MD-tree and the algorithms to perform the insertion, deletion, and spatial searching am described. By the series of simulation tests, the performances of the MD-tree and conventional methods are compared. The results indicate that storage utilization is more than 80% in practice, and that retrieval performance and dynamic characteristics are superior to conventional methods.

关键词： B-TREE BINARY TREE HEIGHT BALANCED TREES HIERARCHICAL data structures GEOGRAPHIC INFORMATION SYSTEM MULTIDIMENSIONAL data structures RANGE QUERIES spatial data structures TREE structures 2-3 TREE

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Continuous versus exclusive classification for fingerprint retrieval

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PATTERN RECOGNITION LETTERS 1997年第10期18卷 1027-1034页

作者： Lumini, A Maio, D Maltoni, D Univ Bologna Corso Laurea Sci Informaz I-47023 Cesena Italy Univ Bologna DEIS CSITE CNR I-40136 Bologna Italy

This work addresses the problem of fingerprint retrieval in a large database. Traditional approaches adopt exclusive classification of fingerprints;the paper shows that a continuous classification can improve the performance of fingerprint retrieval tasks significantly. The proposed approach is based on the extraction of numerical vectors from the directional images of the fingerprints;the retrieval is thus performed in a multidimensional space by using similarity criteria. (C) 1997 Elsevier Science B.V.

关键词： fingerprint classification fingerprint retrieval Karhunen-Loeve transform spatial data structures

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Level compression-based image representation and its applications

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PATTERN RECOGNITION 1998年第3期31卷 327-332页

作者： Chung, KL Hong, KB Natl Taiwan Univ Sci & Technol Dept Informat Management Taipei 10672 Taiwan

In this paper, a level compression-based image representation (LCBIR) is presented. This new image representation method improves the bintree representation for compressing digital binary images. Then we present a fast search algorithm on the LCBIR, which can support fast search and query in pictorial database. Experimental results show that our search algorithm on the LCBIR is faster than the one on the bintree representation.

关键词： spatial data structures bintree image compression level compression search algorithm pictorial database

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Errors in Time-Series Remote Sensing and an Open Access Application for Detecting and Visualizing spatial data Outliers Using Google Earth Engine

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IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING 2019年第4期12卷 1165-1174页

作者： Peter, Brad G. Messina, Joseph P. Michigan State Univ Dept Geog Environm & Spatial Sci E Lansing MI 48823 USA Michigan State Univ Ctr Global Change & Earth Observat E Lansing MI 48823 USA

Remotely sensed measures of productivity are frequently used to characterize global agriculture and vegetated ecosystems, and are often downscaled to describe local, remote areas where finer spatial and temporal resolution data are regularly unavailable. While data errors may propagate throughout any analytical procedure, those that are missed during delivery and preliminary data mining require more attention. Here, a collection of formerly and presently available global remote sensing products are compiled to demonstrate the temporal and geographic breadth of remote sensing uncertainty. Vegetation productivity measures are invaluable for monitoring global health, but erroneous estimates that go unrecognized may result in serious policy mistakes. It is eminently clear that generalizable and accessible a priori methods for anomaly detection are lacking and urgently needed so that data errors are recognized before public delivery and before widespread use. Simple yet effective statistics such as the modified Z-score, Tukey's outliers, and Geary's C are leveraged here to identify, locate, and visualize the types of outliers that remote sensing data users may elect to omit or correct. Contributing to the growing ensemble of Google Earth Engine methodologies, we propose this generalizable method of detecting spatial outliers for remote sensing error management by users across scientific domains.

关键词： data handling error detection coding remote sensing spatial data structures vegetation mapping

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FGNG: A fast multi-dimensional growing neural gas implementation

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NEUROCOMPUTING 2014年第0期128卷 328-340页

作者： Teixeira Mendes, Carlos Augusto Gattass, Marcelo Lopes, Helio Pontificia Univ Catolica Rio de Janeiro Dept Informat Rio De Janeiro Brazil

The Growing Neural Gas algorithm (GNG) is a well-known classification algorithm that is capable of capturing topological relationships that exist in the input data. Unfortunately, simple implementations of the GNG algorithm have time complexity O(n(2)), where n is the number of nodes in the graph. This fact makes these implementations impractical for use in production environments where large data sets are used. This paper aims to propose an optimized implementation that breaks the O(n(2)) barrier and that addresses data in high-dimensional spaces without changing the GNG semantics. The experimental results show speedups of over 50 times for graphs with 200,000 nodes. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Growing neural gas Multi-dimensional data spatial data structures Algorithms

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Privacy-Aware Traffic Monitoring

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IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS 2010年第1期11卷 61-70页

作者： Xie, Hairuo Kulik, Lars Tanin, Egemen Univ Melbourne Natl ICT Australia Victoria Lab Melbourne Vic 3010 Australia Univ Melbourne Dept Comp Sci & Software Engn Melbourne Vic 3010 Australia

Traffic-monitoring systems (TMSs) are vital for safety and traffic optimization. However, these systems may compromise the privacy of drivers once they track the position of each driver with a high degree of temporal precision. In this paper, we argue that aggregated data can protect location privacy while providing accurate information for traffic monitoring. We identify a range of aggregate query types. Our proposed privacy-aware monitoring system (PAMS) works as an aggregate query processor that protects the location privacy of drivers as it anonymizes the IDs of cars. Our experiments show that PAMS answers queries with high accuracy and efficiency.

关键词： Privacy road transportation road vehicle identification road vehicle location monitoring spatial data structures

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A new double sorting-based node splitting algorithm for R-tree

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PROGRAMMING AND COMPUTER SOFTWARE 2012年第3期38卷 109-118页

作者： Korotkov, A. Natl Res Nucl Univ MEPhI Moscow 115522 Russia

A storing of spatial data and processing of spatial queries are important tasks for modern data-bases. The execution efficiency of spatial query depends on underlying index structure. R-tree is a well-known spatial index structure. Currently there exist various versions of R-tree, and one of the most common variations between them is node splitting algorithm. The problem of node splitting in one-dimensional R-tree may seem to be too trivial to be considered separately. One-dimensional intervals can be split on the base of their sorting. Some of the node splitting algorithms for R-tree with two or more dimensions comprise one-dimensional split as their part. However, under detailed consideration, existing algorithms for one-dimensional split do not perform ideally in some complicated cases. This paper introduces a novel one-dimensional node splitting algorithm based on two sortings that can handle such complicated cases better. Also this paper introduces node splitting algorithm for R-tree with two or more dimensions that is based on the one-dimensional algorithm mentioned above. The tests show significantly better behavior of the proposed algorithms in the case of highly overlapping data.

关键词： ALGORITHMS spatial data structures ONE-dimensional flow ALGEBRA FLUID dynamics MATHEMATICS

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GPU-Accelerated Interactive Visualization and Planning of Neurosurgical Interventions

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IEEE COMPUTER GRAPHICS AND APPLICATIONS 2014年第1期34卷 22-31页

作者： Rincon-Nigro, Mario Navkar, Nikhil V. Tsekos, Nikolaos V. Deng, Zhigang Univ Houston Dept Comp Sci Houston TX 77004 USA Univ Houston Houston TX 77004 USA

Advances in computational methods and hardware platforms provide efficient processing of medical-imaging datasets for surgical planning. For neurosurgical interventions employing a straight access path, planning entails selecting a path from the scalp to the target area that's of minimal risk to the patient. A proposed GPU-accelerated method enables interactive quantitative estimation of the risk for a particular path. It exploits acceleration spatial data structures and efficient implementation of algorithms on GPUs. In evaluations of its computational efficiency and scalability, it achieved interactive rates even for high-resolution meshes. A user study and feedback from neurosurgeons identified this methods' potential benefits for preoperative planning and intraoperative replanning.

关键词： GPU acceleration computer graphics interactive visualizations neurosurgical interventions risk maps straight access visualizations Visualization COMPUTER GRAPHICS HAZARD MAPPING Interactive Planning Neurosurgeons Hardware Platform spatial data structures traffic routes

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A new binary image representation: Logicodes

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JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 1997年第3期8卷 291-298页

作者： Wu, JG Chung, KL Natl Taiwan Univ Sci Technol Dept Informat Management Taipei 10672 Taiwan Natl Taiwan Univ Sci Technol Grad Program Informat Engn Taipei 10672 Taiwan Natl Taiwan Normal Univ Dept Informat & Comp Educ Taipei 10610 Taiwan

Using bincodes to represent binary images is shown to be very simple and storage-saving. Given a set of bincodes, this paper presents two improved codes, namely, the logicodes and the restricted logicodes to represent binary images. We first transform the given bincodes into a set of logical expressions. Then a minimization technique is employed to reduce the storage space required for these logical expressions, thus obtaining the logicodes, on which set operations can be applied directly. Further, we put some restrictions into these logicodes to make each resulting logicode, called the restricted logicode, representing a connected black block. Given 20 different-type real images, experimental results show that our logicodes (restricted logicodes) present a saving of 29% to 44% (12% to 34%) with respect to bincodes. When compared to Sarkar's method, except spending a little more space, our proposed codes do have three advantages: (1) it is easier to extract the related geometrical coordinates;(2) the bincodes can be used as direct input;i.e., they do compress the bincodes further;and (3) each restricted logicode represents a connected block block. (C) 1997 Academic Press.

关键词： Binary image compression Bincodes Logical expressions Logicodes Minimization Sarkar's codes Set operations spatial data structures

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A robust software watermarking for copyright protection

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COMPUTERS & SECURITY 2009年第6期28卷 395-409页

作者： Kamel, Ibrahim Albluwi, Qutaiba Sharjah Univ Dept Comp Engn Sharjah U Arab Emirates Queens Univ Sch Comp Kingston ON K7L 3N6 Canada

This paper advocates protecting software copyright through hiding watermarks in various data structures used by the code, e.g., B+-trees, R-trees, linked lists, etc. Prior proposals hide the watermarks in dummy data structures, e.g., linked lists and graphs that are created, solely for this reason, during the execution of the hosting software. This makes them vulnerable to subtractive attacks, because the attacker can remove the dummy data structures without altering the functionality or the semantic of the software program. We argue that hiding watermarks in one or more data structures that are used by the program would make the watermark more robust because disturbing the watermark would affect the semantic and the functionality of the underlying software. The challenge is that the insertion of the watermark should have a minimal effect on the operations and performance of the data structure. This paper proposes a novel method for watermarking R-tree data structure and its variants. The proposed watermarking technique does not change the values of the stored data objects. It takes advantage of the redundancy in the order of entries inside the R-tree nodes. Entries are arranged relative to a "secret" initial order, known only to the software owner, using a technique based on a numbering system that uses variable radix with factorial base. The addition of the watermark in the R-tree data structure does not affect the performance nor does it increase the size of the R-tree. The paper provides a detailed security analysis and performance evaluation to show that the embedded watermarks are robust and can withstand various types of attacks. (C) 2009 Elsevier Ltd. All rights reserved.

关键词： Information security R-trees Watermarking Multimedia indexes spatial data structures Copyright protection

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