Mete Celik, Student Member, Shashi Shekhar, James P. Rogers, James A. Shine
Abstract—Mixed-drove spatio-temporal co-occurrence patterns (MDCOPs) represent subsets of two or more different object-types whose instances are often located in spatial and temporal proximity....
Mete Celik, Shashi Shekhar, James P. Rogers, James A. Shine, Jin Soung Yoo
Detecting IEDs, suspicious vehicles Detecting patterns of enemy troop movement (manpack stinger, tank, and truck)
Graduate Program in Water Resources Science, (2009)
James M. Kang, Shashi Shekhar, Christine Wennen, Paige Novak
Given a percentage-threshold and readings from a pair of consecutive upstream and downstream sensors, flow anomaly discovery identifies dominant time intervals where the fraction of time instants of...
Spatio-temporal Conceptual Schema Development for Wide-Area Sensor Networks (2009)
Mallikarjun Shankar, Re Sorokine, Budhendra Bhaduri, David Resseguie, Shashi Shekhar, Jin Soung Yoo
Abstract. A Wide-Area Sensor Network (WASN) is a collection of heterogeneous sensor networks and data repositories spread over a wide geographic area. The diversity of sensor types and the regional...
TAPER: A two-step approach for all-strong-pairs correlation query in large databases (2008)
Hui Xiong, Shashi Shekhar, Pang-ning Tan, Vipin Kumar
Abstract—Given a user-specified minimum correlation threshold and a market-basket database with N items and T transactions, an all-strong-pairs correlation query finds all item pairs with...
Betsy George, James M. Kang, Shashi Shekhar
Developing a model that facilitates the representation and knowledge discovery on sensor data presents many challenges. With sensors reporting data at a very high frequency, resulting in large...
Vijay G, James M. Kang, Shashi Shekhar, Junchang Ju, Eric D. Kolaczyk, Sucharita Gopal
Many statistical queries such as maximum likelihood estimation involve finding the best candidate model given a set of candidate models and a quality estimation function. This problem is common in...
Spatial Dependency Modeling Using Spatial Auto-Regression * (2008)
Mete Celik, Baris M. Kazar, Shashi Shekhar, Daniel Boley, David J. Lilja
Parameter estimation of the spatial auto-regression model (SAR) is important because we can model the spatial dependency, i.e., spatial autocorrelation present in the geo-spatial data. SAR is a...
Hui Xiong, Shashi Shekhar, Pang-ning Tan, Vipin Kumar
Given a user-specified minimum correlation threshold ¢ and a transaction database with £ items, all-strongpairs correlation query finds all item pairs with correlations above the threshold ¢....
Tensile strength of sawdust reinforced phenolic resin composite materials (2008)
[Abstract]: The basic aim of this project is to study the tensile strength properties of sawdust reinforced phenolic resin composites. The phenolic resin composite materials with sawdust as filler...
Parallelizing Multiscale and Multigranular Spatial Data Mining Algorithms (2008)
Vijay G, Mete Celik, Shashi Shekhar
Multiscale and Multigranular (MSMG) Spatial Data Mining (SDM) algorithms are used to find the best granular class label from a hierarchical set of granular class labels for spatial classification,...
Consistency Checking for Euclidean Spatial Constraints: A Dimension Graph Approach * (2008)
Xuan Liu, Shashi Shekhar, Sanjay Chawla
In this paper, we address the problem of consistency checking for Euclidean spatial constraints. A dimension graph representation is pmposed to maintain the Euclidean spatial constraints among...
Zonal Co-location Pattern Discovery with Dynamic Parameters (2008)
Mete Celik, James M. Kang, Shashi Shekhar
Zonal co-location patterns represent subsets of featuretypes that are frequently located in a subset of space (i.e., zone). Discovering zonal spatial co-location patterns is an important problem with...
Discovering Personal Paths from Sparse GPS Traces (2008)
Changqing Zhou, Shashi Shekhar, Loren Terveen
Personal paths capture “personal meaningful places ” [13, 14] in temporal sequence. Knowledge of a user’s paths enables novel and useful features for location-aware applications, e.g., traffic...
TAPER: A two-step approach for all-strong-pairs correlation query in large databases (2008)
Hui Xiong, Shashi Shekhar, Pang-ning Tan, Vipin Kumar
Given a user-specified minimum correlation threshold θ and a market basket database with N items and T transactions, an all-strong-pairs correlation query finds all item pairs with correlations...
Chapter 3 Trends in Spatial Data Mining (2008)
Shashi Shekhar, Pusheng Zhang, Yan Huang, Raju Vatsavai
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful patterns from large spatial datasets. Extracting interesting and useful patterns from...
Chapter 3 Spatial Data Mining (2008)
Shashi Shekhar, Pusheng Zhang, Yan Huang, Raju Vatsavai
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful patterns from large spatial datasets. Extracting interesting and useful patterns from...
Given a query point and a collection of spatial features, a multi-type nearest neighbor (MTNN) query finds the shortest tour for the query point such that only one instance of each feature is visited...
3 Navigation Systems: A Spatial Database Perspective (2008)
Shashi Shekhar, Ranga Raju Vatsavai, Xiaobin Ma, Jin Soung Yoo
Discovering personally meaningful places: An interactive clustering approach (2008)
Changqing Zhou, Dan Frankowski, Pamela Ludford, Shashi Shekhar, Loren Terveen
The discovery of a person’s meaningful places involves obtaining the physical locations and their labels for a person’s places that matter to his daily life and routines. This problem is driven...
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
Spatial outliers represent locations which are signi®cantly different from their neighborhoods even though they may not be signi®cantly different from the entire population. Identi®cation of...
TAPER: A Two-Step Approach for All-strong-pairs Correlation Query in Large Databases (2008)
Hui Xiong, Student Member, Shashi Shekhar, Vipin Kumar, Pang-ning Tan
Given a user-specified minimum correlation threshold and a market basket database with N items and T transactions, an all-strong-pairs correlation query finds all item pairs with correlations above...
Exploiting A Support-based Upper Bound of Pearson's (2008)
Correlation Coefficient For, Hui Xiong, Shashi Shekhar
Given a user-specified minimum correlation threshold # and a market basket database with N items and T transactions, an all-strong-pairs correlation query finds all item pairs with correlations above...
Trends in Spatial Data Mining (2008)
Shashi Shekhar, Pusheng Zhang, Yan Huang, Ranga Raju Vatsavai
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful patterns from large spatial datasets. Extracting interesting and useful patterns from...
Tensile strength of sawdust reinforced phenolic resin composite materials (2008)
[Abstract]: The basic aim of this project is to study the tensile strength properties of sawdust reinforced phenolic resin composites. The phenolic resin composite materials with sawdust as filler...
Perfect Allocation Methods for Spatial Queries in Parallel Disk Systems. (2007)
A disk-allocation method assigns a disk-id to each unit of spatial data. Allocating spatial data over multiple disks to distribute the I/O cost of query processing uniformly over available disks can...
GIS-T Navigable Databases : A Conceptual Model and Challenges in Using Object Models (2007)
Shashi Shekhar Computer, Shashi Shekhar
this paper to list the challenges in using object data models for GIS-T:
Parallelizing Spatial Databases on Shared-Memory Multiprocessors (2007)
Vipin Kumar, Douglas Chubb, Greg Turner, Shashi Shekhar, Shashi Shekhar, Sivakumar Ravada, ...
Several emerging visualization applications such as flight simulators, distributed interactive simulation (DIS), and virtual reality are using geographic information systems (GISs) for high-fidelity...
Vipin Kumar, Douglas Chubb, Greg Turner, Shashi Shekhar, Shashi Shekhar, Sivakumar Ravada, ...
Several emerging visualization applications such as flight simulators, distributed interactive simulation (DIS), and virtual reality are using geographic information systems (GISs) for high-fidelity...
Shashi Shekhar, Yan Huang, Judy Djugash, Changqing Zhou
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University of Minnesota at Twin-Cities (2007)
Yan Huang, Hui Xiong, Shashi Shekhar, Jian Pei
Mining co-location patterns from spatial databases may reveal types of spatial features likely located as neighbors in space. In this paper, we address the problem of mining con-dent co-location...
Predicting Locations Using Map Similarity(PLUMS): A Framework for Spatial Data Mining * (2007)
Sanjay Chawla, Shashi Shekhar, Weili Wu
Spatial data mining is a process to discover interesting, potentially useful and high utility patterns embedded in spatial databases. Efficient tools for extracting information from spatial data sets...
Pusheng Zhang, Yan Huang, Shashi Shekhar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Applications(A Summary of Results) ABSTRACT (2007)
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Pusheng Zhang, Yan Huang, Shashi Shekhar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
Spatial outliers represent locations which are significantly different from may not be significantly different from the entire population. Identifica discovery of unexpected, interesting, and...
Chapter 3 Spatial Data Mining (2007)
Shashi Shekhar, Pusheng Zhang, Yan Huang, Raju Vatsavai
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful, patterns from large spatial datasets. Extracting interesting and useful patterns from...
IOS Press Detecting graph-based spatial outliers (2007)
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
Abstract. Identification of outliers can lead to the discovery of unexpected and interesting knowledge. Existing methods are designed for detecting spatial outliers in multidimensional geometric data...
Teaching Accomplishments (2007)
Some of my most important teaching is conducted outside the classroom in my role as a research advisor to graduate students. In this role, I advise graduate students to innovate in the context of an...
Spatial Data Mining Research by the Spatial Database Research Group, University of Minnesota (2007)
Shashi Shekhar, Ranga Raju Vatsavai
Explosive growth in geospatial data and the emergence of new spatial technologies emphasize the need for the automated discovery of spatial knowledge. Spatial data mining is the process of...
Performance Evaluation of Co-location Miner (2007)
Shashi Shekhar, Yan Huang, Hui Xiong
Given a collection of boolean spatial features, the co-location pattern discovery process finds the subsets of features frequently located together. For example, the analysis of an ecology dataset...
Using object-oriented database technology to model the real world. Data Models in Geographic (2007)
Shashi Shekhar, Mark Coyle, Brajesh Goyal, Duen-ren Liu, Shyamsundar Sarkar
Information Systems Geographic information systems are used to collect, analyze, and present information describing the physical and logical properties of the geographic world. Geographically...
A Clustering Approach." (2007)
Shashi Shekhar, Chang-tien Lu, Sanjay Chawla, Sivakumar Ravada
ffl Comment: Since the authors are concentrating on spatial join computation, the title should indicate that.
Chapter 1 WHAT'S SPATIAL ABOUT SPATIAL DATA MINING: THREE CASE STUDIES (2007)
Shashi Shekhar, Yan Huang, Weili Wu, C. T. Lu, S. Chawla
Abstract Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful, patterns from large spatial datasets. Extracting interesting and useful patterns...
Shashi Shekhar, Paul R. Schrater, Ranga R. Vatsavai, Weili Wu, Sanjay Chawla
Modeling spatial context (e.g. autocorrelation) is a key challenge in classication problems that arise in geospatial domains. Markov Random Fields (MRFs) is a popular model for incorporating spatial...
Acronym Full form Definition (2007)
Shashi Shekhar, Chang-tien Lu, Sanjay Chawla, Sivakumar Ravada, Graph Section
A Join Index is a data structure used for processing join queries in databases. Join indices use pre-computation techniques to speed up online query processing and are useful for data-sets which are...
Chapter 1 WHAT'S SPATIAL ABOUT SPATIAL DATA MINING: THREE CASE STUDIES (2007)
Shashi Shekhar, Yan Huang, Weili Wu, C. T. Lu, S. Chawla
Abstract Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful, patterns from large spatial datasets. Extracting interesting and useful patterns...
Spatial Cone Tree: An Index Structure for Correlation-based (2007)
Similarity Queries On, Pusheng Zhang, Shashi Shekhar, Vipin Kumar, Yan Huang
this paper, we develop the spatial cone tree, an index structure for spatial time series data. The spatial cone tree groups similar time series together based on spatial proximity. Correlationbased...
What's Spatial About Spatial Data Mining: Three Case Studies (2007)
Shashi Shekhar, Yan Huang, Weili Wu, C. T. Lu
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful, patterns from large spatial datasets. Extracting interesting and useful patterns from...
Ranga R. Vatsavai, Thomas E. Burk, Shashi Shekhar, Maria Gini
Abstract|Traditional statistical classiers rely exclusively on spectral characteristics of multi-dimensional remote sensing imagery, but thematic classes are often spectrally overlapping. The...
Ranga R. Vatsavai, Thomas E. Burk, Paul V. Bolstad, Marvin E. Bauer, Sonja K. Hansen, Tim Mack, ...
Classification of land cover from multi-spectral remotely sensed imagery for large geographic regions requires complex algorithms and feature selection techniques. Statistical classification methods...
Yan Huang, Shashi Shekhar, Hui Xiong
Given a collection of boolean spatial features, the co-location pattern discovery process finds the subsets of features frequently located together. For example, the analysis of an ecology dataset...
Genesis and Advanced Traveler Information Systems (ATIS) : (2007)
Killer Applications For, Shashi Shekhar, Duen-ren Liu
Genesis and ATIS are being developed under the umbrella of the Intelligent Vehicle Highway Systems to facilitate various kinds of travel, including daily commuting to work via private/public...
Vijay G, James Kang, Shashi Shekhar, Vijay G, James M. Kang, Shashi Shekhar
Spatial database research has continued to advance greatly since three decades ago, addressing the growing data management and analysis needs of spatial applications. This research has produced a...
Mining at most top-k mixed-drove spatio-temporal co-occurrence patterns: A summary of results (2007)
Mete Celik, Shashi Shekhar, James P. Rogers, James A. Shine, James M. Kang
Mixed-drove spatio-temporal co-occurrence patterns (MDCOPs) represent subsets of object-types that are located together in space and time. Discovering MDCOPs is an important problem with many...
Continuous evaluation of monochromatic and bichromatic reverse nearest neighbors (2007)
James M. Kang, Mohamed F. Mokbel, Shashi Shekhar, Tian Xia, Donghui Zhang
This paper presents a novel algorithm for Incremental and General Evaluation of continuous Reverse Nearest neighbor queries (IGERN, for short). The IGERN algorithm is general as it is applicable for...
Continuous evaluation of monochromatic and bichromatic reverse nearest neighbors (2007)
James M. Kang, Mohamed F. Mokbel, Shashi Shekhar, Tian Xia, Donghui Zhang
This paper presents a novel algorithm for Incremental and General Evaluation of continuous Reverse Nearest neighbor queries (IGERN, for short). The IGERN algorithm is general as it is applicable for...
Mining at most top-k mixed-drove spatio-temporal co-occurrence patterns: A summary of results (2007)
Shashi Shekhar, James P. Rogers, James A. Shine, James M. Kang
Mixed-drove spatio-temporal co-occurrence patterns (MDCOPs) represent subsets of object-types that are located together in space and time. Discovering MDCOPs is an important problem with many...
Vijay G, James M. Kang, Shashi Shekhar, Junchang Ju, Eric D. Kolaczyk, Sucharita Gopal
Many statistical queries such as maximum likelihood estimation involve finding the best candidate model given a set of candidate models and a quality estimation function. This problem is common in...
Mixed-drove spatio-temporal co-occurrence pattern mining: A summary of results (2006)
Mete Celik, Shashi Shekhar, James P. Rogers, James A. Shine, Jin Soung Yoo
Mixed-drove spatio-temporal co-occurrence patterns (MDCOPs) represent subsets of object-types that are located together in space and time. Discovering MDCOPs is an important problem with many...
Identifying Clusters in Marked Spatial Point Processes: A Summary of Results (2006)
Eep Mane, James Kang, Shashi Shekhar, Jaideep Srivastava, Carson Murray, Anne Pusey, ...
Clustering of marked spatial point process is an important problem in many application domains (e.g. Behavioral Ecology). Classical clustering approaches handle homogeneous spatial points and hence...
Mixed-drove spatio-temporal co-occurrence pattern mining: A summary of results (2006)
Mete Celik, Shashi Shekhar, James P. Rogers, James A. Shine, Jin Soung Yoo
Mixed-drove spatio-temporal co-occurrence patterns (MDCOPs) represent subsets of object-types that are located together in space and time. Discovering MDCOPs is an important problem with many...
Sustained emerging spatio-temporal co-occurrence pattern mining: A summary of results (2006)
Shashi Shekhar, James P. Rogers, James A. Shine
Sustained emerging spatio-temporal co-occurrence patterns (SECOPs) represent subsets of object-types that are increasingly located together in space and time. Discovering SECOPs is important due to...
Capacity Constrained Routing Algorithms for Evacuation Planning: A Summary of Results (2005)
Qingsong Lu, Betsy George, Shashi Shekhar
Abstract. Evacuation planning is critical for numerous important applications, e.g. disaster emergency management and homeland defense preparation. Efficient tools are needed to produce evacuation...
Mining TimeProfiled Associations: An Extended Abstract (2005)
Jin Soung Yoo, Pusheng Zhang, Shashi Shekhar
Abstract. A time-profiled association is an association pattern consistent with a query sequence over time, e.g., identifying the interacting relationship of droughts and wild fires in Australia with...
A join-less approach for co-location pattern mining: A summary of results (2005)
Jin Soung Yoo, Shashi Shekhar, Mete Celik
Spatial co-location patterns represent the subsets of features whose instances are frequently located together in geographic space. Co-location pattern discovery presents challenges since the...
A Partial Join Approach for Mining Co-location Patterns (2004)
Shashi Shekhar, Jin Soung Yoo, Jin Soung Yoo
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Discovering colocation patterns from spatial data sets: a general approach (2004)
Yan Huang, Shashi Shekhar, Hui Xiong
Given a collection of Boolean spatial features, the colocation pattern discovery process finds the subsets of features frequently located together. For example, the analysis of an ecology data set...
Discovering colocation patterns from spatial data sets: a general approach (2004)
Yan Huang, Shashi Shekhar, Hui Xiong
Given a collection of boolean spatial features, the co-location pattern discovery process nds the subsets of features frequently located together. For example, the analysis of an ecology dataset may...
In-Route Nearest Neighbor Queries (2004)
Nearest neighbor query is one of the most important operations in spatial databases and their application domains, such as location-based services and advanced traveler information systems. This...
Spatial data mining: Accomplishments and research needs. Keynote speech at GIScience (2004)
– Microarrays generating gene expression data ⋆ Challenges: • Volume (data) ≫ number of human analysts • Some automation needed ⋆ Data Mining may help! • Provide better and custmized...
Hui Xiong, Shashi Shekhar, Pang-Ning Tan, Vipin Kumar
Given a user-specified minimum correlation threshold # and a market basket database with N items and T transactions, an all-strong-pairs correlation query finds all item pairs with correlations above...
Discovering Personal Gazetteers: An Interactive Clustering Approach (2004)
Changqing Zhou, Dan Frankowski, Pamela Ludford, Shashi Shekhar, Loren Terveen
Personal gazetteers record individuals' most important places, such as home, work, grocery store, etc. Using personal gazetteers in location-aware applications o#ers additional functionality and...
Baris M. Kazar, Shashi Shekhar, David J. Lilja, Daniel Boley
The spatial auto-regression model (SAM) is a popular spatial data mining technique which has been used in many applications with geo-spatial datasets. However, serial procedures for estimating SAM...
A Partial Join Approach for Mining Co-location Patterns (2004)
Spatial co-location patterns represent the subsets of events whose instances are frequently located together in geographic space. We identified the computational bottleneck in the execution time of a...
Baris M. Kazar, Shashi Shekhar, David J. Lilja, Daniel Boley
The spatial auto-regression model (SAM) is a popular spatial data mining technique which has been used in many applications with geo-spatial datasets. However, serial procedures for estimating SAM...
Baris M. Kazar, Shashi Shekhar, David J. Lilja, Ranga R. Vatsavai, R. Kelley Pace
Abstract. The spatial auto-regression (SAR) model is a popular spatial data analysis technique, which has been used in many applications with geo-spatial datasets. However, exact solutions for...
A Partial Join Approach for Mining Co-location Patterns (2004)
Spatial co-location patterns represent the subsets of events whose instances are frequently located together in geographic space. We identified the computational bottleneck in the execution time of a...
Correlation Analysis of Spatial Time Series Datasets: A Filter-and-Refine Approach (2003)
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of interacting elements...
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Evacuation Planning: A Capacity Constrained Routing Approach (2003)
Qingsong Lu, Yan Huang, Shashi Shekhar
Evacuation planning is critical for applications such as disaster management and homeland defense preparation. Ecient tools are needed to produce evacuation plans to evacuate populations to safety in...
Processing In-Route Nearest Neighbor Queries: A Comparison of Alternative Approaches (2003)
Nearest neighbor query is one of the most important operations in spatial databases and their application domains, e.g., locationbased services, advanced traveler information systems, etc. This paper...
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Mining Confident Co-location Rules without A Support Threshold (2003)
Yan Huang, Hui Xiong, Shashi Shekhar
Mining co-location patterns from spatial databases may reveal types of spatial features likely located as neighbors in space. In this paper, we address the problem of mining confident co-location...
Correlation Analysis of Spatial Time Series Datasets: A Filter-and-Refine Approach (2003)
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Processing In-Route Nearest Neighbor Queries: A Comparison of Alternative Approaches (2003)
Nearest neighbor query is one of the most important operations in spatial databases and their application domains, e.g., locationbased services, advanced traveler information systems, etc. This paper...
Hui Xiong, Shashi Shekhar, Pang-ning Tan, Vipin Kumar, Hui Xiong, Shashi Shekhar, ...
Given a user-specified minimum correlation threshold ¢ and a transaction database with £ items, all-strongpairs correlation query finds all item pairs with correlations above the threshold ¢....
Mining Confident Co-location Rules without A Support Threshold (2003)
Yan Huang, Hui Xiong, Shashi Shekhar
ABSTRACT Mining co-location patterns from spatial databases may reveal types of spatial features likely located as neighbors in space. In this paper, we address the problem of mining confident...
Correlation Analysis of Spatial Time Series Datasets: A Filter-and-Refine Approach (2003)
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Shashi Shekhar, Pusheng Zhang, Yan Huang, Raju Vatsavai
Spatial data mining is the process of discovering interesting and previously unknown, but potentially useful patterns from large spatial datasets. Extracting interesting and useful patterns from...
Pusheng Zhang, Yan Huang, Shashi Shekhar, Vipin Kumar
Abstract. A spatial time series dataset is a collection of time series, each referencing a location in a common spatial framework. Correlation analysis is often used to identify pairs of potentially...
Shashi Shekhar, Yan Huang, Judy Djugash
The enormous size of vector maps and limited storage available in hand-held devices motivate the need for data compression techniques. Compression techniques for vector maps can allow PDAs to carry...
Vector Map Compression: A Clustering Approach ACMGIS (2002)
Shashi Shekhar, Yan Huang, Judy Djugash, Changqing Zhou
Vector maps (e.g. road maps) are widely used in a variety of applications such as Geographic Information Systems(GIS), Intelligent Transportation Systems(ITS) and mobile computing. However, the...
Spatial Contextual Classification and Prediction Models for Mining Geospatial Data (2002)
Shashi Shekhar, P. Schrater, Ranga Raju Vatsavai, Sanjay Chawla, Weili Wu
Modeling spatial context (e.g., autocorrelation) is a key challenge in classification problems that arise in geospatial domains. Markov Random Fields (MRFs) is a popular model for in-corporating...
Data Mining for Selective Visualization of Large Spatial Datasets (2002)
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang, Rulin Liu
Data mining is the process of extracting implicit, valuable, and interesting information from large sets of data. Visualization is the process of visually exploring data for pattern and trend...
Data Mining for Selective Visualization of Large Spatial Datasets (2002)
Shashi Shekhar, Pusheng Zhang, Rulin Liu
Data mining is the process of extracting implicit, valuable, and interesting information from large sets of data. Visualization is the process of visually exploring data for pattern and trend...
Spatial Contextual Classification and Prediction Models for Mining Geospatial Data (2002)
Shashi Shekhar, Senior Member, Paul R. Schrater, Ranga R. Vatsavai, Weili Wu, Sanjay Chawla
Modeling spatial context (e.g., autocorrelation) is a key challenge in classification problems that arise in geospatial domains. Markov random fields (MRF) is a popular model for incorporating...
Detecting Graph-based Spatial Outliers (2002)
Shashi Shekhar, Chang-Tien Lu, Pusheng Zhang
Identification of outliers can lead to the discovery of unexpected and interesting knowledge. Existing
Efficient join-index-based spatial-join processing: A clustering approach (2002)
Shashi Shekhar, Senior Member, Chang-tien Lu, Sanjay Chawla, Sivakumar Ravada
Abstract—A join-index is a data structure used for processing join queries in databases. Join-indices use precomputation techniques to speed up online query processing and are useful for data sets...
Vector Map Compression: A Clustering Approach ACMGIS (2002)
Shashi Shekhar, Yan Huang, Judy Djugash, Changqing Zhou
Categories and Subject Descriptors E.4 [Coding and Information Theory]: Data compaction and compression
Discovering spatial co-location patterns: A summary of results (2001)
Abstract. Given a collection of boolean spatial features, the co-location pattern discovery process nds the subsets of features frequently located together. For example, the analysis of an ecology...
Ajay Bhushan P, Jaideep Srivastava, Shashi Shekhar, Ajay Bhushan, Pandey Jaideep, Srivastava Shashi Shekhar
The growth of the World Wide Web has emphasized the need for improved user latency. Primarily, two techniques, i.e., caching and prefetching are being used for improving user latency. Several studies...
Detecting graph-based spatial outliers: algorithms and applications (a summary of results (2001)
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
Identification of outliers can lead to the discovery of unexpected, and interesting knowledge. Existing methods are designed for detecting spatial outliers in multidimensional geometric data sets,...
Detecting graph-based spatial outliers: algorithms and applications (a summary of results (2001)
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
Identi cation of outliers can lead to the discovery of unexpected, interesting, and useful knowledge. Existing methods are designed for detecting spatial outliers in multidimensional geometric data...
Discovering spatial co-location patterns: A summary of results (2001)
Abstract. Given a collection of boolean spatial features, the co-location pattern discovery process finds the subsets of features frequently located together. For example, the analysis of an ecology...
Detecting graph-based spatial outliers: algorithms and applications (a summary of results (2001)
Shashi Shekhar, Chang-tien Lu, Pusheng Zhang
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WMS and GML Based Interoperable Web Mapping System (2001)
Shashi Shekhar, Ranga Raju Vatsavai, Thomas E. Burk, Stephen Lime, Namita Sahay, ...
Recently the World Wide Web has become a popular vehicle for information distribution and web based geographic information systems (GIS) are rapidly evolving and adapting to these new environments....
Modeling Spatial Dependencies for Mining Geospatial Data: An Introduction (2000)
Sanjay Chawla, Shashi Shekhar, Wei Li Wu
Geo-spatial data mining is a process to discover interesting and potentially useful spatial patterns embedded in spatial databases. Efficient tools for extracting information from geo-spatial data...
Extending Data Mining for Spatial Applications: A Case Study in Predicting Nest Locations (2000)
Sanjay Chawla, Shashi Shekhar, Weili Wu, Uygar Ozesmi
Spatial data mining is a process to discover interesting and potentially useful spatial patterns embedded in spatial databases. Efficient tools for extracting information from spatial data sets can...
Consistency Checking for Euclidean Spatial Constraints: A Dimension Graph Approach (2000)
Xuan Liu, Shashi Shekhar, Sanjay Chawla
In this paper, we address the problem of consistency checking for Euclidean spatial constraints. A dimension graph representation is proposed to maintain the Euclidean spatial constraints among...
Processing Object-orientation-based Direction Queries: A summary of Results (2000)
Xuan Liu, Shashi Shekhar, Sanjay Chawla
Direction based spatial relationships are critical in many domains including geographic information systems(GIS) and image interpretation. They are also frequently used as selection conditions in...
Predicting Locations Using Map Similarity (PLUMS): A Framework for Spatial Data Mining (2000)
Sanjay Chawla, Shashi Shekhar, Weili Wu, Uygar Ozesmi
Spatial data mining is a process to discover interesting, potentially useful and high utility patterns embedded in spatial databases. Efficient tools for extracting information from spatial data sets...
Efficient Join-Index-Based Join Processing: A Clustering Approach (1999)
Shashi Shekhar, Chang-tien Lu, Sanjay Chawla, Sivakumar Ravada
A Join Index is a data structure used for processing join queries in databases. Join indices use pre-computation techniques to speed up online query processing and are useful for data-sets which are...
Shashi Shekhar, Ranga Raju Vatsavai, Thomas E. Burk
Abstract. The successful development ofany geographic information system project needs the careful design and implementation of spatial databases via conceptual and logical data-modeling. This...
Xuan Liu, Shashi Shekhar, Sanjay Chawla
Direction based spatial relationships are critical in many domains including geographic information systems(GIS) and image interpretation. They are also frequently used as selection conditions in...
Shashi Shekhar, Ranga Raju Vatsavai, Sanjay Chawla, Thomas E. Burk
. The successful development of any geographic information system project needs the careful design and implementation of spatial databases via conceptual and logical data-modeling. This involves...
Equivalence Classes of Direction Objects and Applications (1999)
Shashi Shekhar, Xuan Liu, Sanjay Chawla
Direction is an important spatial relationship that is used in many fields such as geographic information systems(GIS) and image interpretation. It is also frequently used as a selection condition in...
Shashi Shekhar, Ranga Raju Vatsavai, Sanjay Chawla, Thomas E. Burk
The successful development of any geographic information system project needs the careful design and implementation of spatial databases via conceptual and logical data-modeling. This involves...
High Performance Scalable Capacity Constrained Routing Algorithms for Evacuation Planning (1998)
Capacity constrained route planning tools are vital for increasing the survivability of troops in battlefields and for homeland defense preparation. Efficient tools are needed to produce plans which...
Shekhar, Shashi, Kazar, Baris M., Lilja, David J.
The spatial auto-regression (SAR) model is a popular spatial data analysis technique which has been used in many applications with geo-spatial datasets. However, exact solutions for estimating SAR...
A Partial Join Approach for Mining Co-Location Patterns: A Summary of Results (1998)
Spatial co-location patterns represent the subsets of events whose instances are frequently located together in geographic space. The authors identified the computational bottleneck in the execution...
Capacity Constrained Routing Algorithms for Evacuation Route Planning (1998)
Lu, Qingsong, George, Betsy, Shekhar, Shashi
Evacuation route planning identifies paths in a given transportation network to minimize the time needed to move vulnerable populations to safe destinations. Evacuation route planning is critical for...
Mining Time-Profiled Associations: A Preliminary Study (1998)
Jin Soung Yoo, Jin Soung Yoo, Pusheng Zhang, Pusheng Zhang, Shashi Shekhar, Shashi Shekhar
A time-profiled association is an association pattern consistent with a query sequence along time, e.g., identifying interacting relationship of droughts and wild fires in Australia with the El Nino...
S.Chawla Optimizing Join Index Based Spatial-Join Processing: A Graph Partitioning Approach (1998)
Shashi Shekhar, Chang-tien Lu, Sivakumar Ravada, Sanjay Chawla
A Join Index is a data structure that optimizes the join query processing in spatial databases. Join indices use pre-computation techniques to speed up online query processing and are useful for...
Direction as a Spatial Object: A Summary of Results (1998)
Direction is an important spatial relationship that is used in many fields such as geographic information systems(GIS) and image interpretation. It is also frequently used as a selection condition in...
Optimizing Join Index Based Spatial-Join Processing: (1998)
Graph Partitioning Approach, Shashi Shekhar, Chang-tien Lu, Sivakumar Ravada
A Join Index is a data structure that optimizes the join query processing in spatial databases.
Multilevel hypergraph partitioning: Application in VLSI domain (1997)
George Karypis, Rajat Aggarwal, Vipin Kumar, Senior Member, Shashi Shekhar, Senior Member
Abstract — In this paper, we present a new hypergraphpartitioning algorithm that is based on the multilevel paradigm. In the multilevel paradigm, a sequence of successively coarser hypergraphs is...
Multilevel hypergraph partitioning: Application in VLSI domain (1997)
George Karypis, Rajat Aggarwal, Vipin Kumar, Shashi Shekhar
In this paper, we present a new hypergraph partitioning algorithm that is based on the multilevel paradigm. In the multilevel paradigm, a sequence of successively coarser hypergraphs is constructed....
Multilevel hypergraph partitioning: Application in VLSI domain (1997)
George Karypis, Rajat Aggarwal, Vipin Kumar, Shashi Shekhar
In this paper, we present a new hypergraph partitioning algorithm that is based on the multilevel paradigm. In the multilevel paradigm, a sequence of successively coarser hypergraphs is constructed....
CCAM: A Connectivity-Clustered Access Method for Networks and Network Computations (1997)
CCAM is an access method for general networks. It uses connectivity clustering. The nodes of the network are assigned to disk pages via the graph partitioning approach to maximize the CRR, i.e., the...
CCAM: A Connectivity-Clustered Access Method for Networks and Network Computations (1997)
Current Spatial Database Management Systems (SDBMS) provide efficient access methods and operators for point and range queries over collections of spatial points, line segments, and polygons....
Materialization Trade-Offs in Hierarchical Shortest Path Algorithms (1997)
Shashi Shekhar, Andrew Fetterer, Brajesh Goyal
Materialization and hierarchical routing algorithms are becoming important tools in querying databases for the shortest paths in time-critical applications like Intelligent Transportation Systems...
Multilevel hypergraph partitioning: Application in VLSI domain (1997)
George Karypis, Rajat Aggarwal, Vipin Kumar, Shashi Shekhar
In this paper, we present a new hypergraph partitioning algorithm that is based on the multilevel paradigm. In the multilevel paradigm, a sequence of successively coarser hypergraphs is constructed....
Partitioning Similarity Graphs: A Framework for Declustering Problems (1996)
Declustering problems are well-known in the databases for parallel computing environments. In this paper, we propose a new similarity-based technique for declustering data. The proposed method can...
Genesis: An Approach to Data Dissemination in Advanced Traveler Information Systems (1996)
Shashi Shekhar, Andrew Fetterer, Duen-ren Liu
Genesis and ATIS are being developed under the umbrella of the Intelligent Transportation Systems to facilitate various kinds of travel, including daily commuting to work via private/public...
Partitioning Similarity Graphs: A Framework for Declustering Problems (1996)
Declustering problems are well-known in the databases for parallel computing environments. In this paper, we propose a new similarity-based technique for declustering data. The proposed method can...
Visual Data Mining: Framework and Algorithm Development (1996)
M. Ganesh, Eui-Hong (Sam) Han, Vipin Kumar, Shashi Shekhar, Jaideep Srivastava
Visual data mining is the use of visualization techniques to allow data miners and analysts to evaluate, monitor, and guide the inputs, products and process of data mining. It can help introduce user...
Search Framework for Mining Classification Decision Trees (1996)
Eui-Hong (Sam) Han, Shashi Shekhar, Vipin Kumar, M. Ganesh, Jaideep Srivastava
Classification-rule-learning task is presented as a search process of finding a classification-decision tree that meets users' preferences and requirements. Users can control the efficiency of...
Evaluation of Disk Allocation Methods for Parallelizing Spatial Queries on Grid Files (1995)
Mark Coyle Shashi, Mark Coyle, Shashi Shekhar, Yvonne Zhou
Spatial Database Systems are characterized by large amounts of geometric and geographic data. Query response times in these systems are crucial, since these systems are often used interactively for...
We propose a new similarity-based technique for declustering data. The proposed method can adapt to available information about query distributions, data distributions, data sizes and partition-size...
Load-Balancing in High Performance GIS: Declustering Polygonal Maps (1995)
Vipin Kumar, Douglas Chubb, Greg Turner, Shashi Shekhar, Shashi Shekhar, Sivakumar Ravada, ...
A high performance geographic information system (GIS) is a central component of many real-time applications of spatial decision making. The GIS may contain gigabytes of geometric and feature data...
Vipin Kumar, Shashi Shekhar, Minesh B. Amin
In this paper, we present a new technique for mapping the backpropagation algorithm on hypercubes and related architectures. A key component of this technique is a network partitioning scheme which...
Disk Allocation Methods for Parallelizing Grid Files (1994)
Yvonne Zhou Shashi, Yvonne Zhou, Shashi Shekhar, Mark Coyle
The grid file [1] is a well known access method for multi-dimensional and spatial data. The response time needed to process path and range queries on the grid file access method can be improved...
Shashi Shekhar And, Shashi Shekhar, Duen-ren Liu
Genesis and ATIS are being developed under the umbrella of the Intelligent Vehicle Highway Systems 1 to facilitate various kinds of travel, including daily commuting to work via private/public...
An Evaluation of Access Methods for Spatial Networks (1994)
Current Spatial Database Management Systems (SDBMS) provide efficient access methods and operators for point and range queries over collections of spatial points, line segments, and polygons....
Genesis and ATIS are being developed under the umbrella of the Intelligent Vehicle Highway Systems 1 to facilitate various kinds of travel, including daily commuting to work via private/public...
Resolving Attribute Incompatibility in Database Integration: An Evidential Reasoning Approach (1994)
Ee-Peng Lim, Jaideep Srivastava, Shashi Shekhar
Resolving domain incompatibility among independently developed databases often involves uncertain information. DeMichiel [5] showed that uncertain information can be generated by the mapping of...
Specification and analysis of real-time problem solvers (1993)
Babak Hamidzadeh, Shashi Shekhar
There has been a recent rise in research on real-time problem solving algorithms in artificial intelligence (AI). A real-time AI problem solver performs a task or a set of tasks in two phases. During...
Learning Transformation Rules for Semantic Query Optimization: A Data-Driven Approach (1993)
Shashi Shekhar, Shashi Shekhar, Babak Hamidzadeh, Babak Hamidzadeh, Ashim Kohli, Ashim Kohli, ...
Learning query transformation rules is vital for the success of semantic query optimization in domains where the user cannot provide a comprehensive set of integrity constraints. Finding these rules...
Learning Transformation Rules for Semantic Query Optimization: A Data-Driven Approach (1993)
Shashi Shekhar, Babak Hamidzadeh, Ashim Kohli, D Mark Coyle
Learning query transformation rules is vital for the success of semantic query optimization in domains where the user cannot provide a comprehensive set of integrity constraints. Finding these rules...
Generalization by Neural Networks (1992)
Shashi Shekhar, Minesh B. Amin
Neural networks have traditionally been applied to recognition problems, and most learning algorithms are tailored to those problems. We discuss the requirements of learning for generalization, where...
DYNORAII: A Real-Time Planning Algorithm (1992)
Babak Hamidzadeh, Shashi Shekhar
There has been a recent rise in research on real-time planning algorithms. Most of these algorithms address either the issue of response-time constraints or the issue of dynamic environments.
Cooperating expert systems :--models and techniques /--by Shashi Shekhar. (1989)
Thesis (Ph. D. in Computer Science)--University of California, Berkeley, Dec. 1989.
GIScience 2004- Spatial Data Mining: Accomplishments and Research Needs (1982)
⋆ The process of discovering • interesting,useful, non-trivial patterns • from large spatial datasets ⋆ Spatial patterns • Spatial outlier, discontinuities – bad traffic sensors on...
Shashi Shekhar, Pusheng Zhang, Yan Huang, Ranga Raju Vatsavai
⋆ The process of discovering • interesting,useful, non-trivial patterns • from large spatial datasets ⋆ Spatial patterns • Spatial outlier, discontinuities – bad traffic sensors on...
Spatial Data Mining: Accomplishments and Research Needs (1982)
Pusheng Zhang, Shashi Shekhar, Sky Survey
– Microarrays generating gene expression data ⋆ Challenges: • Volume (data) ≫ number of human analysts • Some automation needed ⋆ Data Mining may help! • Provide better and custmized...
⋆ Sample Local Questions from Epidemiology[TerraSeer] (1982)
Shashi Shekhar, Pusheng Zhang, Yan Huang, Ranga Raju Vatsavai
• How is the global Earth system changing? • What are the primary forcings of the Earth system? • How does the Earth system respond to natural and humanincluded changes? • What are the...
ffl interesting,useful, non-trivial patterns ffl from large spatial datasets? Spatial patterns ffl Spatial outlier, discontinuities- bad traffic sensors on highways (DOT) ffl Location prediction...
Data Models in Geographic Information Systems. (0000)
Geographic information systems (GIS) are used to collect, analyze, the present information describing the physical and logical properties of the geographic world. Geographically referenced data is...
Data Models in Geographic Information Systems.
Geographic information systems (GIS) are used to collect, analyze, the present information describing the physical and logical properties of the geographic world. Geographically referenced data is...
Consistency Checking for Euclidean Spatial Constraints: A Dimension Graph Approach
Xuan Liu Shashi, Xuan Liu, Shashi Shekhar, Sanjay Chawla
In this paper, we address the problem of consistency checking for Euclidean spatial constraints. A dimension graph representation is proposed to maintain the Euclidean spatial constraints among...
Processing Object-Orientation-based Direction Queries in Spatial Databases
Xuan Liu, Shashi Shekhar, Sanjay Chawla
Direction based spatial relationships are critical in many domains including geographic information systems(GIS) and image interpretation. They are also frequently used as selection conditions in...
Processing Object-Orientation-based Direction Queries in Spatial Databases
Xuan Liu Shashi, Xuan Liu, Shashi Shekhar, Sanjay Chawla
Direction based spatial relationships are critical in many domains including geographic information systems(GIS) and image interpretation. They are also frequently used as selection conditions in...
Declustering and Load-Balancing Methods for Parallelizing Geographic Information Systems
Vipin Kumar, Douglas Chubb, Greg Turner, Shashi Shekhar, Shashi Shekhar, Sivakumar Ravada, ...
Declustering and load-balancing are important issues in designing a high performance geographic information system (HPGIS) which is a central component of many interactive applications such as...
Declustering and Load-Balancing Methods for Parallelizing Geographic Information Systems
Vipin Kumar, Douglas Chubb, Greg Turner, Shashi Shekhar, Shashi Shekhar, Sivakumar Ravada, ...
Declustering and load-balancing are important issues in designing a high performance geographic information system (HPGIS) which is a central component of many interactive applications such as...