Open Access. Powered by Scholars. Published by Universities.®

OS and Networks Commons™

Open Access. Powered by Scholars. Published by Universities.®

Databases and Information Systems

Institution
Keyword
Publication Year
Publication
Publication Type

Articles 571 - 600 of 858

Full-Text Articles in OS and Networks

What, Where And When: Supporting Semantic, Spatial And Temporal Queries In A Dbms, Matthew Perry, Amit P. Sheth, Farshad Hakimpour, Prateek Jain Jan 2007

What, Where And When: Supporting Semantic, Spatial And Temporal Queries In A Dbms, Matthew Perry, Amit P. Sheth, Farshad Hakimpour, Prateek Jain

Kno.e.sis Publications

Spatial and temporal data are critical components in many applications. This is especially true in analytical domains such as national security and criminal investigation. The outcome of the analytical process in these applications often hinges on uncovering and analyzing complex relationships between disparate people, places and events. Fundamentally new query operators based on the graph structure of Semantic Web data models, such as semantic associations, are proving useful in these applications. However, these analysis mechanisms are primarily intended for thematic relationships. We describe a framework built around the RDF metadata model for analysis of thematic, spatial and temporal relationships between …

Go to article

Collecting Expertise Of Researchers For Finding Relevant Experts In A Peer-Review Setting, Delroy H. Cameron, Boanerges Aleman-Meza, Ismailcem Budak Arpinar Jan 2007

Collecting Expertise Of Researchers For Finding Relevant Experts In A Peer-Review Setting, Delroy H. Cameron, Boanerges Aleman-Meza, Ismailcem Budak Arpinar

Kno.e.sis Publications

We present ideas for determining the expertise of researchers across various areas of computer science and for finding relevant experts/reviewers in a peer review setting. We explain how Semantic Web techniques for data collection and data representation using ontologies can be used in addressing this specific 'ExpertFinder' problem.

Go to article

Brief Announcement: Space Adaptation: Privacy-Preserving Multiparty Collaborative Mining With Geometric Perturbation, Keke Chen, Ling Liu Jan 2007

Brief Announcement: Space Adaptation: Privacy-Preserving Multiparty Collaborative Mining With Geometric Perturbation, Keke Chen, Ling Liu

Kno.e.sis Publications

No abstract provided.

Go to article

Evolution And Maintenance Of Frequent Pattern Space When Transactions Are Removed, Mengling Feng, Guozhu Dong, Jinyan Li, Yap-Peng Tan, Limsoon Wong Jan 2007

Evolution And Maintenance Of Frequent Pattern Space When Transactions Are Removed, Mengling Feng, Guozhu Dong, Jinyan Li, Yap-Peng Tan, Limsoon Wong

Kno.e.sis Publications

This paper addresses the maintenance of discovered frequent patterns when a batch of transactions are removed from the original dataset. We conduct an in-depth investigation on how the frequent pattern space evolves under transaction removal updates using the concept of equivalence classes. Inspired by the evolution analysis, an effective and exact algorithm TRUM is proposed to maintain frequent patterns. Experimental results demonstrate that our algorithm outperforms representative state-of-the-art algorithms.

Go to article

Direct Code Access In Self-Organizing Neural Networks For Reinforcement Learning, Ah-Hwee Tan Jan 2007

Direct Code Access In Self-Organizing Neural Networks For Reinforcement Learning, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

TD-FALCON is a self-organizing neural network that incorporates Temporal Difference (TD) methods for reinforcement learning. Despite the advantages of fast and stable learning, TD-FALCON still relies on an iterative process to evaluate each available action in a decision cycle. To remove this deficiency, this paper presents a direct code access procedure whereby TD-FALCON conducts instantaneous searches for cognitive nodes that match with the current states and at the same time provide maximal reward values. Our comparative experiments show that TD-FALCON with direct code access produces comparable performance with the original TD-FALCON while improving significantly in computation efficiency and network complexity.

Go to article

Regression Cubes With Lossless Compression And Aggregation, Yixin Chen, Guozhu Dong, Jiawei Han, Jian Pei, Benjamin W. Wah, Jianyong Wang Dec 2006

Regression Cubes With Lossless Compression And Aggregation, Yixin Chen, Guozhu Dong, Jiawei Han, Jian Pei, Benjamin W. Wah, Jianyong Wang

Kno.e.sis Publications

As OLAP engines are widely used to support multidimensional data analysis, it is desirable to support in data cubes advanced statistical measures, such as regression and filtering, in addition to the traditional simple measures such as count and average. Such new measures will allow users to model, smooth, and predict the trends and patterns of data. Existing algorithms for simple distributive and algebraic measures are inadequate for efficient computation of statistical measures in a multidimensional space. In this paper, we propose a fundamentally new class of measures, compressible measures, in order to support efficient computation of the statistical models. For …

Go to article

Implicit Online Learning With Kernels, Li Cheng, S. V. N. Vishwanathan, Dale Schuurmans, Shaojun Wang, Terry Caelli Dec 2006

Implicit Online Learning With Kernels, Li Cheng, S. V. N. Vishwanathan, Dale Schuurmans, Shaojun Wang, Terry Caelli

Kno.e.sis Publications

We present two new algorithms for online learning in reproducing kernel Hilbert spaces. Our first algorithm, ILK (implicit online learning with kernels), employs a new, implicit update technique that can be applied to a wide variety of convex loss functions. We then introduce a bounded memory version, SILK (sparse ILK), that maintains a compact representation of the predictor without compromising solution quality, even in non-stationary environments. We prove loss bounds and analyze the convergence rate of both. Experimental evidence shows that our proposed algorithms outperform current methods on synthetic and real data.

Go to article

Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang Nov 2006

Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang

Computer Science Faculty Publications

Previous analytical results on the resilience of unstructured P2P systems have not explicitly modeled heterogeneity of user churn (i.e., difference in online behavior) or the impact of in-degree on system resilience. To overcome these limitations, we introduce a generic model of heterogeneous user churn, derive the distribution of the various metrics observed in prior experimental studies (e.g., lifetime distribution of joining users, joint distribution of session time of alive peers, and residual lifetime of a randomly selected user), derive several closed-form results on the transient behavior of in-degree, and eventually obtain the joint in/out degree isolation probability as a simple …

Go to article

{Ontology: Resource} X {Matching : Mapping} X {Schema : Instance} :: Components Of The Same Challenge, Amit P. Sheth Nov 2006

{Ontology: Resource} X {Matching : Mapping} X {Schema : Instance} :: Components Of The Same Challenge, Amit P. Sheth

Kno.e.sis Publications

Ontologies enable us to elevate syntactic and structural processing in an information system/Web to an information system/Web powered with semantic processing. Experience has shown that monolithic and tightly coupled approaches seldom succeed, and majority of information systems and applications will need to deal with plurality of ontologies in a loosely coupled environment (i.e., independently evolving ontologies and inter-ontology relationships, existence of different contexts for different users/applications etc.) Development of such loosely-coupled multi-ontology environments entails development of techniques for ontology mapping/alignment, multi-ontology query processing, and much more.

Go to article

Active Semantic Electronic Medical Record, Amit P. Sheth, Sangeeta Agrawal, Jonathan Lathem, Nicole Oldham, H. Wingate, K. Gallagher Nov 2006

Active Semantic Electronic Medical Record, Amit P. Sheth, Sangeeta Agrawal, Jonathan Lathem, Nicole Oldham, H. Wingate, K. Gallagher

Kno.e.sis Publications

The healthcare industry is rapidly advancing towards the widespread use of electronic medical records systems to manage the increasingly large amount of patient data and reduce medical errors. In addition to patient data there is a large amount of data describing procedures, treatments, diagnoses, drugs, insurance plans, coverage, formularies and the relationships between these data sets. While practices have benefited from the use of EMRs, infusing these essential programs with rich domain knowledge and rules can greatly enhance their performance and ability to support clinical decisions. Active Semantic Electronic Medical Record (ASEMR) application discussed here uses Semantic Web technologies to …

Go to article

On The Complexity Of Horn Description Logics, Markus Krotzsch, Sebastian Rudolph, Pascal Hitzler Nov 2006

On The Complexity Of Horn Description Logics, Markus Krotzsch, Sebastian Rudolph, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Horn-SHIQ has been identified as a fragment of the description logic SHIQ for which inferencing is in PTIME with respect to the size of the ABox. This enables reasoning with larger ABoxes in situations where the TBox is static, and represents one approach towards tractable description logic reasoning. In this paper, we show that reasoning in Horn-SHIQ, in spite of its low datacomplexity, is ExpTIME-hard with respect to the overall size of the knowledge base. While this result is not unexpected, the proof is not a mere modification of existing reductions since …

Go to article

A Framework For Schema-Driven Relationship Discovery From Unstructured Text, Cartic Ramakrishnan, Krzysztof Kochut, Amit P. Sheth Nov 2006

A Framework For Schema-Driven Relationship Discovery From Unstructured Text, Cartic Ramakrishnan, Krzysztof Kochut, Amit P. Sheth

Kno.e.sis Publications

We address the issue of extracting implicit and explicit relationships between entities in biomedical text. We argue that entities seldom occur in text in their simple form and that relationships in text relate the modified, complex forms of entities with each other. We present a rule-based method for (1) extraction of such complex entities and (2) relationships between them and (3) the conversion of such relationships into RDF. Furthermore, we present results that clearly demonstrate the utility of the generated RDF in discovering knowledge from text corpora by means of locating paths composed of the extracted relationships.

Go to article

How To Reason With Owl In A Logic Programming System, Markus Krotzsch, Pascal Hitzler, Denny Vrandecic, Michael Sintek Nov 2006

How To Reason With Owl In A Logic Programming System, Markus Krotzsch, Pascal Hitzler, Denny Vrandecic, Michael Sintek

Computer Science and Engineering Faculty Publications

Logic programming has always been a major ontology modeling paradigm, and is frequently being used in large research projects and industrial applications, e.g., by means of the F-Logic reasoning engine OntoBroker or the TRIPLE query, inference, and transformation language and system. At the same time, the Web Ontology Language OWL has been recommended by the W3C for modeling ontologies for the Web. Naturally, it is desirable to investigate the interoperability between both paradigms. In this paper, we do so by studying an expressive fragment of OWL DL for which reasoning can be reduced to the evaluation of Horn logic programs. …

Go to article

Semantic Interoperability Of Web Services - Challenges And Experiences, Meenakshi Nagarajan, Kunal Verma, Amit P. Sheth, John A. Miller, Jonathan Lathem Sep 2006

Semantic Interoperability Of Web Services - Challenges And Experiences, Meenakshi Nagarajan, Kunal Verma, Amit P. Sheth, John A. Miller, Jonathan Lathem

Kno.e.sis Publications

With the rising popularity of Web services, both academia and industry have invested considerably in Web service description standards, discovery, and composition techniques. The standards based approach utilized by Web services has supported interoperability at the syntax level. However, issues of structural and semantic heterogeneity between messages exchanged by Web services are far more complex and crucial to interoperability. It is for these reasons that we recognize the value that schema/data mappings bring to Web service descriptions. In this paper, we examine challenges to interoperability; classify the types of heterogeneities that can occur between interacting services and present a possible …

Go to article

Optimal Adaptation In Web Processes With Coordination Constraints, Kunal Verma, Prashant Doshi, Karthik Gomadam, John A. Miller, Amit P. Sheth Sep 2006

Optimal Adaptation In Web Processes With Coordination Constraints, Kunal Verma, Prashant Doshi, Karthik Gomadam, John A. Miller, Amit P. Sheth

Kno.e.sis Publications

We present methods for optimally adapting Web processes to exogenous events while preserving inter-service constraints that necessitate coordination. For example, in a supply chain process, orders placed by a manufacturer may get delayed in arriving. In response to this event, the manufacturer has the choice of either waiting out the delay or changing the supplier. Additionally, there may be compatibility constraints between the different orders, thereby introducing the problem of coordination between them if the manufacturer chooses to change the suppliers. We focus on formulating the decision making models of the managers, who must adapt to external events while satisfying …

Go to article

Flexible Querying Of Xml Documents, Krishnaprasad Thirunarayan, Trivikram Immaneni Sep 2006

Flexible Querying Of Xml Documents, Krishnaprasad Thirunarayan, Trivikram Immaneni

Kno.e.sis Publications

Text search engines are inadequate for indexing and searching XML documents because they ignore metadata and aggregation structure implicit in the XML documents. On the other hand, the query languages supported by specialized XML search engines are very complex. In this paper, we present a simple yet flexible query language, and develop its semantics to enable intuitively appealing extraction of relevant fragments of information while simultaneously falling back on retrieval through plain text search if necessary. We also present a simple yet robust relevance ranking for heterogeneous document-centric XML.

Go to article

Multi-Learner Based Recursive Supervised Training, Laxmi R. Iyer, Kiruthika Ramanathan, Sheng-Uei Guan Sep 2006

Multi-Learner Based Recursive Supervised Training, Laxmi R. Iyer, Kiruthika Ramanathan, Sheng-Uei Guan

Research Collection School Of Computing and Information Systems

In this paper, we propose the multi-learner based recursive supervised training (MLRT) algorithm, which uses the existing framework of recursive task decomposition, by training the entire dataset, picking out the best learnt patterns, and then repeating the process with the remaining patterns. Instead of having a single learner to classify all datasets during each recursion, an appropriate learner is chosen from a set of three learners, based on the subset of data being trained, thereby avoiding the time overhead associated with the genetic algorithm learner utilized in previous approaches. In this way MLRT seeks to identify the inherent characteristics of …

Go to article

Optimal Adaptation Of Web Processes With Inter-Service Dependencies, Kunal Verma, Prashant Doshi, Karthik Gomadam, John A. Miller, Amit P. Sheth Jul 2006

Optimal Adaptation Of Web Processes With Inter-Service Dependencies, Kunal Verma, Prashant Doshi, Karthik Gomadam, John A. Miller, Amit P. Sheth

Kno.e.sis Publications

We present methods for optimally adapting Web processes to exogenous events while preserving inter-service dependencies. For example, in a supply chain process, orders placed by the manufacturer may get delayed in arriving. In response to this event, the manufacturer has the choice of either waiting out the delay or changing the supplier. Additionally, there may be compatibility constraints between the different orders, thereby introducing the problem of coordination between them if the manufacturer chooses to change the suppliers. We present our methods within the framework of autonomic Web processes. This framework seeks to add properties of self-configuration, adaptation, and self-optimization …

Go to article

Querying Formal Contexts With Answer Set Programs, Pascal Hitzler, Markus Krotzsch Jul 2006

Querying Formal Contexts With Answer Set Programs, Pascal Hitzler, Markus Krotzsch

Computer Science and Engineering Faculty Publications

Recent studies showed how a seamless integration of formal concept analysis (FCA), logic of domains, and answer set programming (ASP) can be achieved. Based on these results for combining hierarchical knowledge with classical rule-based formalisms, we introduce an expressive common-sense query language for formal contexts. Although this approach is conceptually based on order-theoretic paradigms, we show how it can be implemented on top of standard ASP systems. Advanced features, such as default negation and disjunctive rules, thus become practically available for processing contextual data.

Go to article

Geospatial Ontology Development And Semantic Analytics, I. Budak Arpinar, Cartic Ramakrishnan, Molly Azami, Amit P. Sheth, E. Lynn Usery, Mei-Po Kwan Jul 2006

Geospatial Ontology Development And Semantic Analytics, I. Budak Arpinar, Cartic Ramakrishnan, Molly Azami, Amit P. Sheth, E. Lynn Usery, Mei-Po Kwan

Kno.e.sis Publications

Geospatial ontology development and semantic knowledge discovery addresses the need for modeling, analyzing and visualizing multimodal information, and is unique in offering integrated analytics that encompasses spatial, temporal and thematic dimensions of information and knowledge. The comprehensive ability to provide integrated analysis from multiple forms of information and use of explicit knowledge make this approach unique. This also involves specification of spatiotemporal thematic ontologies and populating such ontologies with high quality knowledge. Such ontologies form the basis for defining the meaning of important relations terms, such as near or surrounded by, and enable computation of spatiotemporal thematic proximity measures we …

Go to article

Masquerader Detection Using Oclep: One-Class Classification Using Length Statistics Of Emerging Patterns, Lijun Chen, Guozhu Dong Jun 2006

Masquerader Detection Using Oclep: One-Class Classification Using Length Statistics Of Emerging Patterns, Lijun Chen, Guozhu Dong

Kno.e.sis Publications

We introduce a new method for masquerader detection that only uses a user’s own data for training, called Oneclass Classification using Length statistics of Emerging Patterns (OCLEP). Emerging patterns (EPs) are patterns whose support increases from one dataset/class to another with a big ratio, and have been very useful in earlier studies. OCLEP classifies a case T as self or masquerader by using the average length of EPs obtained by contrasting T against sets of samples of a user’s normal data. It is based on the observation that one needs long EPs to differentiate instances from a common class, but …

Go to article

Interacting With Web Hierarchies, Saverio Perugini, Naren Ramakrishnan Jun 2006

Interacting With Web Hierarchies, Saverio Perugini, Naren Ramakrishnan

Computer Science Faculty Publications

Web site interfaces are a particularly good fit for hierarchies in the broadest sense of that idea, i.e. a classification with multiple attributes, not necessarily a tree structure. Several adaptive interface designs are emerging that support flexible navigation orders, exposing and exploring dependencies, and procedural information-seeking tasks. This paper provides a context and vocabulary for thinking about hierarchical Web sites and their design. The paper identifies three features that interface to information hierarchies. These are flexible navigation orders, the ability to expose and explore dependencies, and support for procedural tasks. A few examples of these features are also provided

Go to article

A Metamodel And Uml Profile For Rule-Extended Owl Dl Ontologies, Saartje Brockmans, Peter Haase, Pascal Hitzler, Rudi Studer Jun 2006

A Metamodel And Uml Profile For Rule-Extended Owl Dl Ontologies, Saartje Brockmans, Peter Haase, Pascal Hitzler, Rudi Studer

Computer Science and Engineering Faculty Publications

In this paper we present a MOF compliant metamodel and UML profile for the Semantic Web Rule Language (SWRL) that integrates with our previous work on a metamodel and UML profile for OWL DL. Based on this metamodel and profile, UML tools can be used for visual modeling of rule-extended ontologies.

Go to article

Semantic Empowerment Of Health Care And Life Science Applications, Amit P. Sheth May 2006

Semantic Empowerment Of Health Care And Life Science Applications, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Go to article

Semantic Analytics Visualization, Leonidas Deligiannidis, Amit P. Sheth, Boanerges Aleman-Meza May 2006

Semantic Analytics Visualization, Leonidas Deligiannidis, Amit P. Sheth, Boanerges Aleman-Meza

Kno.e.sis Publications

In this paper we present a new tool for semantic analytics through 3D visualization called “Semantic Analytics Visualization” (SAV). It has the capability for visualizing ontologies and meta-data including annotated web-documents, images, and digital media such as audio and video clips in a synthetic three-dimensional semi-immersive environment. More importantly, SAV supports visual semantic analytics, whereby an analyst can interactively investigate complex relationships between heterogeneous information. The tool is built using Virtual Reality technology which makes SAV a highly interactive system. The backend of SAV consists of a Semantic Analytics system that supports query processing and semantic association discovery. Using a …

Go to article

Ivibrate: Interactive Visualization Based Framework For Clustering Large Datasets, Keke Chen, Ling Liu Apr 2006

Ivibrate: Interactive Visualization Based Framework For Clustering Large Datasets, Keke Chen, Ling Liu

Kno.e.sis Publications

With continued advances in communication network technology and sensing technology, there is astounding growth in the amount of data produced and made available through cyberspace. Efficient and high-quality clustering of large datasets continues to be one of the most important problems in large-scale data analysis. A commonly used methodology for cluster analysis on large datasets is the three-phase framework of sampling/summarization, iterative cluster analysis, and disk-labeling. There are three known problems with this framework which demand effective solutions. The first problem is how to effectively define and validate irregularly shaped clusters, especially in large datasets. Automated algorithms and statistical methods …

Go to article

Detecting The Change Of Clustering Structure In Categorical Data Streams, Keke Chen, Ling Liu Apr 2006

Detecting The Change Of Clustering Structure In Categorical Data Streams, Keke Chen, Ling Liu

Kno.e.sis Publications

Analyzing clustering structures in data streams can provide critical information for making decision in real time. In this paper, we present a framework for detecting the change of critical clustering structure in categorical data streams. The framework consists of the Hierarchical Entropy Tree structure (HE-Tree) and the extended ACE clustering algorithm. HE-Tree can efficiently capture the entropy property of the categorical data streams and allow us to draw precise clustering information from the data stream for high-quality BkPLots with the extended ACE algorithm.

Go to article

Semantic Web Applications In Financial Industry, Government, Health Care And Life Sciences, Amit P. Sheth Mar 2006

Semantic Web Applications In Financial Industry, Government, Health Care And Life Sciences, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Go to article

Wsdl-S: Specification, Tools, Use Cases And Applications, Amit P. Sheth, Kunal Verma, Karthik Gomadam Mar 2006

Wsdl-S: Specification, Tools, Use Cases And Applications, Amit P. Sheth, Kunal Verma, Karthik Gomadam

Kno.e.sis Publications

No abstract provided.

Go to article

Visual Ontology Modeling For Electronic Markets, Saartje Brockmans, Andreas Geyer-Schulz, Pascal Hitzler, Rudi Studer Jan 2006

Visual Ontology Modeling For Electronic Markets, Saartje Brockmans, Andreas Geyer-Schulz, Pascal Hitzler, Rudi Studer

Computer Science and Engineering Faculty Publications

The research program, Information Management and Market Engineering, focuses on the analysis and the design of electronic markets. Taking a holistic view of the conceptualization and realization of solutions, the research integrates the disciplines business administration, economics, computer science, and law. Topics of interest range from the implementation, quality assurance, and further development of electronic markets to their integration into business processes, innovative business models, and legal frameworks.

Go to article

First Prev Next Last