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Articles 10441 - 10470 of 10627

Full-Text Articles in Life Sciences

Boltzmann Machine Learning With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao Aug 2003

Boltzmann Machine Learning With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao

Kno.e.sis Publications

We present a new statistical learning paradigm for Boltzmann machines based on a new inference principle we have proposed: the latent maximum entropy principle (LME). LME is different both from Jaynes maximum entropy principle and from standard maximum likelihood estimation. We demonstrate the LME principle BY deriving new algorithms for Boltzmann machine parameter estimation, and show how robust and fast new variant of the EM algorithm can be developed. Our experiments show that estimation based on LME generally yields better results than maximum likelihood estimation, particularly when inferring hidden units from small amounts of data.

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Learning Mixture Models With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao Aug 2003

Learning Mixture Models With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao

Kno.e.sis Publications

We present a new approach to estimating mixture models based on a new inference principle we have proposed: the latent maximum entropy principle (LME). LME is different both from Jaynes’ maximum entropy principle and from standard maximum likelihood estimation. We demonstrate the LME principle by deriving new algorithms for mixture model estimation, and show how robust new variants of the EM algorithm can be developed. Our experiments show that estimation based on LME generally yields better results than maximum likelihood estimation, particularly when inferring latent variable models from small amounts of data.

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Genetic Polymorphisms Of The Interleukin-1 Gene And Early Marginal Bone Loss Around Endosseous Dental Implants, Hitomi Shimpuku, Yasuhiro Nosaka, Tatsuya Kawamura, Yoichi Tachi, Mitsuko Shinohara, Kiyoshi Ohura Aug 2003

Genetic Polymorphisms Of The Interleukin-1 Gene And Early Marginal Bone Loss Around Endosseous Dental Implants, Hitomi Shimpuku, Yasuhiro Nosaka, Tatsuya Kawamura, Yoichi Tachi, Mitsuko Shinohara, Kiyoshi Ohura

Faculty, Staff and Student Publications

Dental implant surgery commonly proceeds in two stages. It is generally accepted that bone loss around implants does not occur at stage-II surgery because implants do not receive mechanical loading. However, early marginal bone loss around implants occasionally does occur during the healing period. Genetic polymorphisms in the interleukin-1 (IL-1) gene have been reported to be important for bone homeostasis and susceptibility to bone disease. We therefore investigated whether the idiopathic early marginal bone loss around implants is related to polymorphisms in the IL-1 gene. We performed a case-control study. Patients demonstrating marginal bone loss around implants at stage-II surgery …

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A Visual Framework Invites Human Into The Clustering Process, Keke Chen, Ling Liu Jul 2003

A Visual Framework Invites Human Into The Clustering Process, Keke Chen, Ling Liu

Kno.e.sis Publications

Clustering is a technique commonly used in scientific research. The task of clustering inevitably involves human participation - the clustering is not finished when the computer/algorithm finishes but the user has evaluated, understood and accepted the patterns. This defines a human involved "clustering-analysis/evaluation" iteration. Instead of neglecting this human involvement, we provide a visual framework (VISTA) with all power of algorithmic approaches (since their result can be visualized), and in addition we allow the user to steer/monitor/refine the clustering process with domain knowledge. The visual-rendering result also provides a precise pattern for fast post-processing.

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Toward A Comprehensive Supplement For Language Courses, Krishnaprasad Thirunarayan, Stephen P. Carl Jul 2003

Toward A Comprehensive Supplement For Language Courses, Krishnaprasad Thirunarayan, Stephen P. Carl

Kno.e.sis Publications

No abstract provided.

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Fast And Space-Efficient Location Of Heavy Or Dense Segments In Run-Length Encoded Sequences, Ronald I. Greenberg Jul 2003

Fast And Space-Efficient Location Of Heavy Or Dense Segments In Run-Length Encoded Sequences, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This paper considers several variations of an optimization problem with potential applications in such areas as biomolecular sequence analysis and image processing. Given a sequence of items, each with a weight and a length, the goal is to find a subsequence of consecutive items of optimal value, where value is either total weight or total weight divided by total length. There may also be a specified lower and/or upper bound on the acceptable length of subsequences. This paper shows that all the variations of the problem are solvable in linear time and space even with non-uniform item lengths and divisible …

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Cluster Stability Scores For Microarray Data In Cancer Studies, Mark Smolkin, Debashis Ghosh Jun 2003

Cluster Stability Scores For Microarray Data In Cancer Studies, Mark Smolkin, Debashis Ghosh

The University of Michigan Department of Biostatistics Working Paper Series

A potential benefit of profiling of tissue samples using microarrays is the generation of molecular fingerprints that will define subtypes of disease. Hierarchical clustering has been the primary analytical tool used to define disease subtypes from microarray experiments in cancer settings. Assessing cluster reliability poses a major complication in analyzing output from these procedures. While much work has been done on assessing the global question of number of clusters in a dataset, relatively little research exists on assessing stability of individual clusters. A potential benefit of profiling of tissue samples using microarrays is the generation of molecular fingerprints that will …

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Adding Semantics To Web Services Standards, Kaarthik Sivashanmugam, Kunal Verma, Amit P. Sheth, John Miller Jun 2003

Adding Semantics To Web Services Standards, Kaarthik Sivashanmugam, Kunal Verma, Amit P. Sheth, John Miller

Kno.e.sis Publications

With the increasing growth in popularity of Web services, discovery of relevant Web services becomes a significant challenge. One approach is to develop semantic Web services where by the Web services are annotated based on shared ontologies, and use these annotations for semantics-based discovery of relevant Web services. We discuss one such approach that involves adding semantics to WSDL using DAML+OIL ontologies. Our approach also uses UDDI to store these semantic annotations and search for Web services based on them. We compare our approach with another initiative to add semantics to support Web service discovery, and show how our approach …

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Semantic Web Process Lifecycle: Role Of Semantics In Annotation, Discovery, Composition And Orchestration, Amit P. Sheth May 2003

Semantic Web Process Lifecycle: Role Of Semantics In Annotation, Discovery, Composition And Orchestration, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Healthcare Enterprise Process Development And Integration, Kemafor Anyanwu, Amit P. Sheth, Jorge Cardoso, John A. Miller, Krzysztof J. Kochut May 2003

Healthcare Enterprise Process Development And Integration, Kemafor Anyanwu, Amit P. Sheth, Jorge Cardoso, John A. Miller, Krzysztof J. Kochut

Kno.e.sis Publications

Healthcare enterprises involve complex processes that span diverse groups and organisations. These processes involve clinical and administrative tasks, large volumes of data, and large numbers of patients and personnel. The tasks can be performed either by humans or by automated systems. In the latter case, the tasks are supported by a variety of software applications and information systems which are very often heterogeneous, autonomous, and distributed. The development of systems to manage and automate these processes has increasingly played an important role in improving the efficiency of healthcare enterprises. In this paper we look at four healthcare and medical applications …

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Ρ-Queries: Enabling Querying For Semantic Associations On The Semantic Web, Kemafor Anyanwu, Amit P. Sheth May 2003

Ρ-Queries: Enabling Querying For Semantic Associations On The Semantic Web, Kemafor Anyanwu, Amit P. Sheth

Kno.e.sis Publications

This paper presents the notion of Semantic Associations as complex relationships between resource entities. These relationships capture both a connectivity of entities as well as similarity of entities based on a specific notion of similarity called ρ-isomorphism. It formalizes these notions for the RDF data model, by introducing a notion of a Property Sequence as a type. In the context of a graph model such as that for RDF, Semantic Associations amount to specific certain graph signatures. Specifically, they refer to sequences (i.e. directed paths) here called Property Sequences, between entities, networks of Property Sequences (i.e. undirected paths), or subgraphs …

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Exception Handling For Conflict Resolution In Cross-Organizational Workflows, Zongwei Luo, Amit P. Sheth, Krzysztof Kochut, I. Budak Arpinar May 2003

Exception Handling For Conflict Resolution In Cross-Organizational Workflows, Zongwei Luo, Amit P. Sheth, Krzysztof Kochut, I. Budak Arpinar

Kno.e.sis Publications

Workflow management systems (WfMSs) are being increasingly deployed to deliver e-business transactions across organizational boundaries. To ensure a high service quality in such transactions, exception-handling schemes for conflict resolution are needed. The conflicts primarily arise due to failure of a task in workflow execution because of underlying application, or controlling WfMS component failures or insufficient user input. So far, little progress has been reported in addressing conflict resolution in cross-organizational business processes, though its importance has been recognized. In this paper, we identify the exception handling techniques that support conflict resolution in cross-organizational settings. In particular, we propose a novel, …

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Identifying Patterns In Dna Change, Jason R. Gilder, Dan E. Krane, Travis E. Doom, Michael L. Raymer Apr 2003

Identifying Patterns In Dna Change, Jason R. Gilder, Dan E. Krane, Travis E. Doom, Michael L. Raymer

Kno.e.sis Publications

Now that a draft sequence of the human genome is nearly complete, questions regarding both the information contained within our genetic blueprints as well as the manner in which that information content changes over time can be addressed in ways that had not previously been possible. By their very nature, some of the nucleotide sequences present within our genome allow detailed examination of the mode and pattern of evolution that has shaped our genetic instructions over time spans of tens of millions of years. Alu repeats are one example. Using these relatively short, ubiquitous DNA sequences we explore the problem …

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Ontology Driven Information Systems In Action (Capturing And Applying Existing Knowledge To Semantic Applications), Amit P. Sheth Mar 2003

Ontology Driven Information Systems In Action (Capturing And Applying Existing Knowledge To Semantic Applications), Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Simple Parallel Statistical Computing In R, Anthony Rossini, Luke Tierney, Na Li Mar 2003

Simple Parallel Statistical Computing In R, Anthony Rossini, Luke Tierney, Na Li

UW Biostatistics Working Paper Series

Theoretically, many modern statistical procedures are trivial to parallelize. However, practical deployment of a parallelized implementation which is robust and reliably runs on different computational cluster configurations and environments is far from trivial. We present a framework for the R statistical computing language that provides a simple yet powerful programming interface to a computational cluster. This interface allows the development of R functions that distribute independent computations across the nodes of the computational cluster. The resulting framework allows statisticians to obtain significant speed-ups for some computations at little additional development cost. The particular implementation can be deployed in heterogeneous computing …

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Literate Statistical Practice, Anthony Rossini, Friedrich Leisch Mar 2003

Literate Statistical Practice, Anthony Rossini, Friedrich Leisch

UW Biostatistics Working Paper Series

Literate Statistical Practice (LSP, Rossini, 2001) describes an approach for creating self-documenting statistical results. It applies literate programming (Knuth, 1992) and related techniques in a natural fashion to the practice of statistics. In particular, documentation, specification, and descriptions of results are written concurrently with writing and evaluation of statistical programs. We discuss how and where LSP can be integrated into practice and illustrate this with an example derived from an actual statistical consulting project. The approach is simplified through the use of a comprehensive, open source toolset incorporating Noweb, Emacs Speaks Statistics (ESS), Sweave (Ramsey, 1994; Rossini, et al, 2002; …

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Generalized Metrics And Uniquely Determined Logic Programs, Pascal Hitzler, Anthony K. Seda Jan 2003

Generalized Metrics And Uniquely Determined Logic Programs, Pascal Hitzler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

The introduction of negation into logic programming brings the benefit of enhanced syntax and expressibility, but creates some semantical problems. Specifically, certain operators which are monotonic in the absence of negation become non-monotonic when it is introduced, with the result that standard approaches to denotational semantics then become inapplicable. In this paper, we show how generalized metric spaces can be used to obtain fixed-point semantics for several classes of programs relative to the supported model semantics, and investigate relationships between the underlying spaces we employ. Our methods allow the analysis of classes of programs which include the acyclic, locally hierarchical, …

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Semantic N-Gram Language Modeling With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao Jan 2003

Semantic N-Gram Language Modeling With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao

Kno.e.sis Publications

We describe a unified probabilistic framework for statistical language modeling-the latent maximum entropy principle-which can effectively incorporate various aspects of natural language, such as local word interaction, syntactic structure and semantic document information. Unlike previous work on maximum entropy methods for language modeling, which only allow explicit features to be modeled, our framework also allows relationships over hidden features to be captured, resulting in a more expressive language model. We describe efficient algorithms for marginalization, inference and normalization in our extended models. We then present experimental results for our approach on the Wall Street Journal corpus.

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Tools And Approaches For The Construction Of Knowledge Models From The Neuroscientific Literature, Gully Burns, Arshad Khan, Shahram Ghandeharizadeh, Mark O'Neill, Yi-Shin Chen Jan 2003

Tools And Approaches For The Construction Of Knowledge Models From The Neuroscientific Literature, Gully Burns, Arshad Khan, Shahram Ghandeharizadeh, Mark O'Neill, Yi-Shin Chen

Selected Works Temporary Series

Within this paper, we describe a neuroinformatics project (called "NeuroScholar," http://www.neuroscholar.org/) that enables researchers to examine, manage, manipulate, and use the information contained within the published neuroscientific literature. The project is built within a multi-level, multi-component framework constructed with the use of software engineering methods that themselves provide code-building functionality for neuroinformaticians. We describe the different software layers of the system. First, we present a hypothetical usage scenario illustrating how NeuroScholar permits users to address large-scale questions in a way that would otherwise be impossible. We do this by applying NeuroScholar to a "real-world" neuroscience question: How is stress-related information …

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Web Service: Been There, Done That?, Steffen Staab, Will Van Der Aalst, V. Richard Benjamins, Amit P. Sheth, John A. Miller, Chistoph Bussler, Alexander Maedche, Dieter Fensel, Dennis Gannon Jan 2003

Web Service: Been There, Done That?, Steffen Staab, Will Van Der Aalst, V. Richard Benjamins, Amit P. Sheth, John A. Miller, Chistoph Bussler, Alexander Maedche, Dieter Fensel, Dennis Gannon

Kno.e.sis Publications

Web services can be defined as loosely coupled, reusable software components that semantically encapsulate discrete functionality and are distributed and programmatically accessible over standard Internet protocols. Web services have received a lot of hype, the reasons for which are not easily determined. Some of their benefits might even seem to waste away, once we touch on the nitty-gritty details, because Web services per se do not offer a solution to underlying problems. The contributions included in this section delve into some of these issues, including: pitfalls of workflow issues; structuring procedural knowledge into problem-solving methods; discussing how a low initial …

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Tools And Approaches For The Construction Of Knowledge Models From The Neuroscientific Literature, Burns, Arshad Khan, Shahram Ghandeharizadeh, Mark O'Neill, Yi-Shin Chen Jan 2003

Tools And Approaches For The Construction Of Knowledge Models From The Neuroscientific Literature, Burns, Arshad Khan, Shahram Ghandeharizadeh, Mark O'Neill, Yi-Shin Chen

Departmental Papers (Biology)

Within this paper, we describe a neuroinformatics project (called "NeuroScholar," http://www.neuroscholar.org/) that enables researchers to examine, manage, manipulate, and use the information contained within the published neuroscientific literature. The project is built within a multi-level, multi-component framework constructed with the use of software engineering methods that themselves provide code-building functionality for neuroinformaticians. We describe the different software layers of the system. First, we present a hypothetical usage scenario illustrating how NeuroScholar permits users to address large-scale questions in a way that would otherwise be impossible. We do this by applying NeuroScholar to a "real-world" neuroscience question: How is stress-related information …

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An Extended Hierarchical Task Analysis For Error Prediction In Medical Devices, Phillip H. Chung, Jiajie Zhang, Todd R. Johnson, Vimla L. Patel Jan 2003

An Extended Hierarchical Task Analysis For Error Prediction In Medical Devices, Phillip H. Chung, Jiajie Zhang, Todd R. Johnson, Vimla L. Patel

Faculty, Staff and Student Publications

This paper introduces an extended hierarchical task analysis (HTA) methodology devised to evaluate and compare user interfaces on volumetric infusion pumps. The pumps were studied along the dimensions of overall usability and propensity for generating human error. With HTA as our framework, we analyzed six pumps on a variety of common tasks using Norman’s Action theory. The introduced method of evaluation divides the problem space between the external world of the device interface and the user’s internal cognitive world, allowing for predictions of potential user errors at the human-device level. In this paper, one detailed analysis is provided as an …

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Semantic Web Processes, Jorge Cardoso, Amit P. Sheth Jan 2003

Semantic Web Processes, Jorge Cardoso, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Formal Concept Analysis And Resolution On Algebraic Domains - Preliminary Report, Matthias Wendt, Pascal Hitzler Jan 2003

Formal Concept Analysis And Resolution On Algebraic Domains - Preliminary Report, Matthias Wendt, Pascal Hitzler

Computer Science and Engineering Faculty Publications

We relate two formerly independent areas: Formal concept analysis and logic of domains. We will establish a correspondence between contextual attribute logic on formal contexts resp. concept lattices and a clausal logic on coherent algebraic cpos. We show how to identify the notion of formal concept in the domain theoretic setting. In particular, we show that a special instance of the resolution rule from the domain logic coincides with the concept closure operator from formal concept analysis. The results shed light on the use of contexts and domains for knowledge representation and reasoning purposes.

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Learning Continuous Latent Variable Models With Bregman Divergences, Shaojun Wang, Dale Schuurmans Jan 2003

Learning Continuous Latent Variable Models With Bregman Divergences, Shaojun Wang, Dale Schuurmans

Kno.e.sis Publications

We present a class of unsupervised statistical learning algorithms that are formulated in terms of minimizing Bregman divergences— a family of generalized entropy measures defined by convex functions. We obtain novel training algorithms that extract hidden latent structure by minimizing a Bregman divergence on training data, subject to a set of non-linear constraints which consider hidden variables. An alternating minimization procedure with nested iterative scaling is proposed to find feasible solutions for the resulting constrained optimization problem. The convergence of this algorithm along with its information geometric properties are characterized.

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Encouraging Adolescents Toward Mental Health Careers Via Website Biographies, Irmi U. Willcockson, Prabhu R. Shankar, Cynthia L. Phelps, Craig W. Johnson Jan 2003

Encouraging Adolescents Toward Mental Health Careers Via Website Biographies, Irmi U. Willcockson, Prabhu R. Shankar, Cynthia L. Phelps, Craig W. Johnson

Faculty, Staff and Student Publications

This project designed, developed, implemented and is currently evaluating the effectiveness of an interactive, multi-media website designed to encourage adolescents to consider careers in mental health. This Web-based learning environment features biographies of mental health scientists. Evaluation is conducted in a systematic, structured way using cognitive achievement, usability (ease of use), and affective scales (e.g., fun to use) as outcome measures

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Rigorously Assessing Whether The Data Backs The Back School, David T. Vinh, Craig W. Johnson, Cynthia L. Phelps Jan 2003

Rigorously Assessing Whether The Data Backs The Back School, David T. Vinh, Craig W. Johnson, Cynthia L. Phelps

Faculty, Staff and Student Publications

A rigorous between-subjects methodology employing independent random samples and having broad clinical applicability was designed and implemented to evaluate the effectiveness of back safety and patient transfer training interventions for both hospital nurses and nursing assistants. Effects upon self-efficacy, cognitive, and affective measures are assessed for each of three back safety procedures. The design solves the problem of obtaining randomly assigned independent controls where all experimental subjects must participate in the training interventions.

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Randomized Comparisons Among Health Informatics Students Identify Hypertutorial Features As Improving Web-Based Instruction, Craig W. Johnson, Yan Xing, Lan Yang Jan 2003

Randomized Comparisons Among Health Informatics Students Identify Hypertutorial Features As Improving Web-Based Instruction, Craig W. Johnson, Yan Xing, Lan Yang

Faculty, Staff and Student Publications

Hypertutorials optimize five features - presentation, learner control, practice, feedback, and elaborative learning resources. Previous research showed graduate students significantly and overwhelmingly preferred Web-based hypertutorials to conventional "Book-on-the-Web" statistics or research design lessons. The current report shows that the source of hypertutorials' superiority in student evaluations of instruction lies in their hypertutorial features. Randomized comparisons between the two methodologies were conducted in two successive iterations of a graduate level health informatics research design and evaluation course. The two versions contained the same text and graphics, but differed in the presence or absence of hypertutorial features: Elaborative learning resources, practice, feedback, …

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The Physician's Perception Of Medical Error And Its Application To The Development Of An Educational Training Tool, Johnny E. Bates, Cynthia Phelps, Craig W. Johnson Jan 2003

The Physician's Perception Of Medical Error And Its Application To The Development Of An Educational Training Tool, Johnny E. Bates, Cynthia Phelps, Craig W. Johnson

Faculty, Staff and Student Publications

It is becoming clear that if we are to impact the rate of medical errors it will have to be done at the practicing physician level. The purpose of this project was to survey the attitude of physicians in Alabama concerning their perception of medical error, and to obtain their thoughts and desires for medical education in the area of medical errors. The information will be used in the development of a physician education program.

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Web Service Technologies And Their Synergy With Simulation, Senthilanand Chandrasekaran, Gregory S. Silver, John A. Miller, Jorge Cardoso, Amit P. Sheth Dec 2002

Web Service Technologies And Their Synergy With Simulation, Senthilanand Chandrasekaran, Gregory S. Silver, John A. Miller, Jorge Cardoso, Amit P. Sheth

Kno.e.sis Publications

The World Wide Web has had a huge influence on the computing field in general as well as simulation in particular (e.g., Web-Based Simulation). A new wave of development based upon XML has started. Two of the most interesting aspects of this development are the Semantic Web and Web Services. This paper examines the synergy between Web service technology and simulation. In one direction, Web service processes can be simulated for the purpose of correcting/improving the design. In the other direction, simulation models/components can be built out of Web services. Work on seamlessly using simulation as a part of Web …

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