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Full-Text Articles in Engineering

On The Discovery Of Social Roles In Large Scale Social Systems, Derek Doran Dec 2015

On The Discovery Of Social Roles In Large Scale Social Systems, Derek Doran

Computer Science and Engineering Faculty Publications

The social role of a participant in a social system is a label conceptualizing the circumstances under which she interacts within it. They may be used as a theoretical tool that explains why and how users participate in an online social system. Social role analysis also serves practical purposes, such as reducing the structure of complex systems to relationships among roles rather than alters, and enabling a comparison of social systems that emerge in similar contexts. This article presents a data-driven approach for the discovery of social roles in large scale social systems. Motivated by an analysis of the present …


The Effect Of A Reversible Shear Transformation On Plastic Deformation Of An Amorphous Solid, Nikolai V. Priezjev Sep 2015

The Effect Of A Reversible Shear Transformation On Plastic Deformation Of An Amorphous Solid, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

Molecular dynamics simulations are performed to investigate the plastic response of a model glass to a local shear transformation in a quiescent system. The deformation of the material is induced by a spherical inclusion that is gradually strained into an ellipsoid of the same volume and then reverted back into the sphere. We show that the number of cage-breaking events increases with increasing strain amplitude of the shear transformation. The results of numerical simulations indicate that the density of cage jumps is larger in the cases of weak damping or slow shear transformation. Remarkably, we also found that, for a …


Analysis Of A Clinically Failed, Mechanically Intact, Reconstructive Compression Plate, Bharadwaj Cheruvu, Sunil Karmacharya, Richard T. Laughlin, Tarun Goswami Sep 2015

Analysis Of A Clinically Failed, Mechanically Intact, Reconstructive Compression Plate, Bharadwaj Cheruvu, Sunil Karmacharya, Richard T. Laughlin, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

A reconstructive orthopedic bone plate was submitted for analysis. Traditional failure analysis methods were used to assess the mode of the plate failure. Metallographic investigation of the plate was carried out in this report. Since limited data was available in the literature and clinical data related to subject demography, date of removal as well as reasons for removal unknown, in depth analysis was not possible. However, the plate was received in in-tact condition with minor biological deposits and scratches, it is speculated that the failure of the plate may have been due to biological/clinical reasons, likely infection, rejecting the device …


Stay Awhile And Listen: User Interactions In A Crowdsourced Platform Offering Emotional Support, Derek Doran, Samir P. Yelne, Luisa Massari, Maria-Carla Calzarossa, Latrelle D. Jackson, Glen Moriarty Aug 2015

Stay Awhile And Listen: User Interactions In A Crowdsourced Platform Offering Emotional Support, Derek Doran, Samir P. Yelne, Luisa Massari, Maria-Carla Calzarossa, Latrelle D. Jackson, Glen Moriarty

Computer Science and Engineering Faculty Publications

Internet and online-based social systems are rising as the dominant mode of communication in society. However, the public or semi-private environment under which most online communications operate under do not make them suitable channels for speaking with others about personal or emotional problems. This has led to the emergence of online platforms for emotional support offering free, anonymous, and confidential conversations with live listeners. Yet very little is known about the way these platforms are utilized, and if their features and design foster strong user engagement. This paper explores the utilization and the interaction features of hundreds of thousands of …


Safety And Efficacy Results Of Switch From Imiglucerase To Velaglucerase Alfa Treatment In Patients With Type 1 Gaucher Disease, Deborah Elstein, Atul Mehta, Derralynn A. Hughes, Pilar Giraldo, Joel Charrow, Laurie Smith, Suma P. Shankar, Thomas N. Hangartner, Yune Kunes, Nan Wang, Eric Crombez, Ari Zimran Jul 2015

Safety And Efficacy Results Of Switch From Imiglucerase To Velaglucerase Alfa Treatment In Patients With Type 1 Gaucher Disease, Deborah Elstein, Atul Mehta, Derralynn A. Hughes, Pilar Giraldo, Joel Charrow, Laurie Smith, Suma P. Shankar, Thomas N. Hangartner, Yune Kunes, Nan Wang, Eric Crombez, Ari Zimran

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Gaucher disease (GD) is a lysosomal storage disorder; symptomatic patients with type 1 GD need long-term disease-specific therapy of which the standard of care has been enzyme replacement therapy (ERT). Thirty-eight of 40 patients (aged 9–71 years) clinically stable on ERT with imiglucerase, safely switched to a comparable dose of velaglucerase alfa (units/kg) during TKT034, a 12-month, open-label clinical study, and for 10–50 months in an extension study. The most common adverse events (AEs) judged to be drug-related in the extension were fatigue and bone pain. No drug-related serious AEs were reported. No AEs led to study withdrawal. At 24 …


Velaglucerase Alfa (Vpriv) Enzyme Replacement Therapy In Patients With Gaucher Disease: Long-Term Data From Phase Iii Clinical Trials, Derralynn A. Hughes, Derlis Gonzalez, Elena A. Lukina, Atul Mehta, Madhulika Kabra, Deborah Elstein, Isaac Kisinovsky, Pilar Giraldo, Ashish Bavdekar, Thomas N. Hangartner, Nan Wang, Eric Crombez, Ari Zimran Jul 2015

Velaglucerase Alfa (Vpriv) Enzyme Replacement Therapy In Patients With Gaucher Disease: Long-Term Data From Phase Iii Clinical Trials, Derralynn A. Hughes, Derlis Gonzalez, Elena A. Lukina, Atul Mehta, Madhulika Kabra, Deborah Elstein, Isaac Kisinovsky, Pilar Giraldo, Ashish Bavdekar, Thomas N. Hangartner, Nan Wang, Eric Crombez, Ari Zimran

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Type 1 Gaucher disease is an inherited lysosomal enzyme deficiency with variable age of symptom onset. Common presenting signs include thrombocytopenia, anemia, hepatosplenomegaly, bone abnormalities, and, additionally in children, growth failure. Fifty-seven patients aged 3–62 years at the baseline of two phase III trials for velaglucerase alfa treatment were enrolled in the single extension study. In the extension, they received every-other-week velaglucerase alfa intravenous infusions for 1.2–4.8 years at 60 U/kg, although 10 patients experienced dose reduction. No patient experienced a drug-related serious adverse event or withdrew due to an adverse event. One patient died following a convulsion that was …


Diffusion Of A Janus Nanoparticle In An Explicit Solvent: A Molecular Dynamics Simulation Study, Ali Kharazmi, Nikolai V. Priezjev Jun 2015

Diffusion Of A Janus Nanoparticle In An Explicit Solvent: A Molecular Dynamics Simulation Study, Ali Kharazmi, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

Molecular dynamics simulations are carried out to study the translational and rotational diffusion of a single Janus particle immersed in a dense Lennard-Jones fluid. We consider a spherical particle with two hemispheres of different wettabilities. The analysis of the particle dynamics is based on the time-dependent orientation tensor, particle displacement, as well as the translational and angular velocity autocorrelation functions. It was found that both translational and rotational diffusion coefficients increase with decreasing surface energy at the nonwetting hemisphere, provided that the wettability of the other hemisphere remains unchanged. We also observed that in contrast to homogeneous particles, the nonwetting …


Toe Joint Replacement Models, Tarun Goswami, Allison L. Van Horn, Alexander O. Sheets Jun 2015

Toe Joint Replacement Models, Tarun Goswami, Allison L. Van Horn, Alexander O. Sheets

Biomedical, Industrial & Human Factors Engineering Faculty Publications

In various embodiments, provided are implantable devices for replacing all or a portion of a metatarsophalangeal joint, comprising (i) a metatarsal component comprising a Substan tially convex bearing Surface; or (ii) a phalanx component comprising a Substantially concave bearing Surface; or (iii) both. In various embodiments, also provided are methods of treating hallux Valgus by replacing all or a portion of a meta tarsophalangeal joint with one or more of the provided implantable devices.


Where Do We Develop? Discovering Regions For Urban Investment In Senegal, Derek Doran, Andrew Fox, Veena Mendiratta Apr 2015

Where Do We Develop? Discovering Regions For Urban Investment In Senegal, Derek Doran, Andrew Fox, Veena Mendiratta

Computer Science and Engineering Faculty Publications

The rate of urbanization in developing countries, defined as the speed with which a population shifts from rural to urban areas, is among the highest in the world. The disproportionate number of citizens that live in a small numbers of cities places incredible pressure on the largest cities in these countries, which may already be faced with limited resources, weak industrialization, and underdeveloped infrastructures. Urban planning researchers as well as policy makers have suggested that governments in developing countries make capital investments within and surrounding smaller cities to attract citizens away from large urban centers, thereby lowering the pressure placed …


Oculomotor Neurocircuitry, A Structural Connectivity Study Of Infantile Nystagmus Syndrome, Nasser H. Kashou, Angelica R. Zampini Apr 2015

Oculomotor Neurocircuitry, A Structural Connectivity Study Of Infantile Nystagmus Syndrome, Nasser H. Kashou, Angelica R. Zampini

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Infantile Nystagmus Syndrome (INS) is one of the leading causes of significant vision loss in children and affects about 1 in 1000 to 6000 births. In the present study, we are the first to investigate the structural pathways of patients and controls using diffusion tensor imaging (DTI). Specifically, three female INS patients from the same family were scanned, two sisters and a mother. Six regions of interest (ROIs) were created manually to analyze the number of tracks. Additionally, three ROI masks were analyzed using TBSS (Tract-Based Spatial Statistics). The number of fiber tracks was reduced in INS subjects, compared to …


Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev Mar 2015

Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that are identified based on the relative displacement of atoms before and after the shear transformation. We find that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of …


Compensatory Enlargement Of Ossabaw Miniature Swine Coronary Arteries In Diffuse Atherosclerosis, Jenny Susana Choy, Tong Luo, Yunlong Huo, Thomas Wischgoll, Kyle Schultz, Shawn D. Teague, Michael Sturek, Ghassan S. Kassab Mar 2015

Compensatory Enlargement Of Ossabaw Miniature Swine Coronary Arteries In Diffuse Atherosclerosis, Jenny Susana Choy, Tong Luo, Yunlong Huo, Thomas Wischgoll, Kyle Schultz, Shawn D. Teague, Michael Sturek, Ghassan S. Kassab

Computer Science and Engineering Faculty Publications

Studies in human and non-human primates have confirmed the compensatory enlargement or positive remodeling (Glagov phenomenon) of coronary vessels in the presence of focal stenosis. To our knowledge, this is the first study to document arterial enlargement in a metabolic syndrome animal model with diffuse coronary artery disease (DCAD) in the absence of severe focal stenosis. Two different groups of Ossabaw miniature pigs were fed a high fat atherogenic diet for 4 months (Group I) and 12 months (Group II), respectively. Group I (6 pigs) underwent contrast enhanced computed tomographic angiography (CCTA) and intravascular ultrasound (IVUS) at baseline and after …


Finite Element Analysis Of System-Level Electronic Packages For Space Applications, Adrien Lambert, Ahsan Mian, Justin Hogan, Todd Kaiser, Brock Lameres Jan 2015

Finite Element Analysis Of System-Level Electronic Packages For Space Applications, Adrien Lambert, Ahsan Mian, Justin Hogan, Todd Kaiser, Brock Lameres

Mechanical and Materials Engineering Faculty Publications

Thermal analysis was required in order to aid in the design and testing of a radiation tolerant computing (RTC) system using a radiation sensor. During development of the system, different test beds were employed in order to characterize the radiation sensor and its supporting electronic systems. The most common preliminary tests are high altitude balloon tests which allow the sensor to experience cosmic radiation at high altitudes, consistent with space flight operations. In this study, finite element analysis (FEA) was used to evaluate primary system architecture, system support structures, and the flight payload in order to determine if the system …


Multifunctional Nanomaterials For Biomedical Engineering: Unique Properties, Fabrications, And Diverse Applications, Jen-Jie Chieh, Sharmila M. Mukhopadhyay, Yali Cui Jan 2015

Multifunctional Nanomaterials For Biomedical Engineering: Unique Properties, Fabrications, And Diverse Applications, Jen-Jie Chieh, Sharmila M. Mukhopadhyay, Yali Cui

Mechanical and Materials Engineering Faculty Publications

Nanomaterials possess many unique properties useful for biomedical applications ranging from preoperative and intraoperative imaging to coatings, assays, and cell scaffolds. Their popularity and production value are full of competitiveness. Their related methodologies and instruments are also created or emphasized as the mainstream. Since multifunctional nanomaterials attract interests and attention of researchers, engineers, and businessmen in biomedical engineering, this journal is set up to publish a special issue devoted to this topic. The result is a collection of five original research articles, whose authors belong to academic or research institutions of five different countries from Asia, Europe, and America. Papers …


A Probabilistic Fracture Assessment Of Vertebral Cortical Bone, Tarun Goswami, Isaac Mabe Jan 2015

A Probabilistic Fracture Assessment Of Vertebral Cortical Bone, Tarun Goswami, Isaac Mabe

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Cortical bone is a material with a porous structure. The presence of pores creates local stress concentrations and the likelihood of premature failure. Assuming that pores are present in all bone, vertebral endplates, for example, can subside. Subsidence has taken place at rates as high as 77 percent. A computational probabilistic assessment of the pore size distribution and their contribution to the fracture toughness has been presented in this paper. A Monte Carlo simulation was used to develop and assign random pores. Also the model compared crack sizes to the thickness of the cortical bone present as a limiting case. …


Distributed Owl El Reasoning: The Story So Far, Raghava Mutharaju, Pascal Hitzler, Prabhaker Mateti Oct 2014

Distributed Owl El Reasoning: The Story So Far, Raghava Mutharaju, Pascal Hitzler, Prabhaker Mateti

Computer Science and Engineering Faculty Publications

Automated generation of axioms from streaming data, such as traffic and text, can result in very large ontologies that single machine reasoners cannot handle. Reasoning with large ontologies requires distributed solutions. Scalable reasoning techniques for RDFS, OWL Horst and OWL 2 RL now exist. For OWL 2 EL, several distributed reasoning approaches have been tried, but are all perceived to be inefficient. We analyze this perception. We analyze completion rule based distributed approaches, using different characteristics, such as dependency among the rules, implementation optimizations, how axioms and rules are distributed. We also present a distributed queue approach for the classification …


Pushing The Boundaries Of Tractable Ontology Reasoning, David Carral, Cristina Feier, Bernardo Cuenca Grau, Pascal Hitzler, Ian Horrocks Oct 2014

Pushing The Boundaries Of Tractable Ontology Reasoning, David Carral, Cristina Feier, Bernardo Cuenca Grau, Pascal Hitzler, Ian Horrocks

Computer Science and Engineering Faculty Publications

We identify a class of Horn ontologies for which standard reasoning tasks such as instance checking and classification are tractable. The class is general enough to include the OWL 2 EL, QL, and RL profiles. Verifying whether a Horn ontology belongs to the class can be done in polynomial time. We show empirically that the class includes many real-world ontologies that are not included in any OWL 2 profile, and thus that polynomial time reasoning is possible for these ontologies.


Effect Of Anthropometric Adjustments On Bmd And Bmc Z-Scores In A Population Of Prader-Willi Syndrome Pediatric Patients, Amanda E. Marker, David F. Short, Talia Eldar-Geva, Harry J. Hirsch, Varda Gross-Tsur, Maayan Tiomkin, Ari Zimran, Thomas N. Hangartner Oct 2014

Effect Of Anthropometric Adjustments On Bmd And Bmc Z-Scores In A Population Of Prader-Willi Syndrome Pediatric Patients, Amanda E. Marker, David F. Short, Talia Eldar-Geva, Harry J. Hirsch, Varda Gross-Tsur, Maayan Tiomkin, Ari Zimran, Thomas N. Hangartner

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Two adjustment models were applied to a dataset of bone-mineral density (BMD) and bone-mineral content (BMC) from dual-energy x-ray absorptiometry (DXA) measurements of pediatric patients with Prader-Willi Syndrome (PWS). One model used weight, height and % body fat (WHF) in the calculation of Z-scores in addition to race, sex and age already included in the standard model. As percent body fat is not always available, a second model with only weight and height was also examined (WH).


Wear Characteristics Of Wright State University Total Ankle Replacement Under Shear And Torsion Loads, Tarun Goswami Oct 2014

Wear Characteristics Of Wright State University Total Ankle Replacement Under Shear And Torsion Loads, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Introduction: Total ankle replacement (TAR) involves replacement of the damaged bone with prosthetic components and is usually performed in patients suffering with arthritis to relieve pain and maintain motion. There are several different factors that contribute to failure of TARs but aseptic loosening is the primary method of failure in total ankle replacements. Because of its superior mechanical properties UHMWPE is used as a liner material in TARs. Wear generated from the liner due to high contact stresses during gait causes osteolysis resulting in early loosening of the prostheses.

Most of the earlier studies have focused on wear due to …


Metabolomics Characterization Of U.S. And Japanese F-15 And C-130 Flight Line Crews Exposed To Jet Fuel Volatile Organic Compounds And Aerosols, Nicholas J. Delraso, David Mattie, Asao Kobayashi, Stephen W. Mitchell, Scott Dillard, Michael L. Raymer, Isaie Sibomana, Nicholas V. Reo Sep 2014

Metabolomics Characterization Of U.S. And Japanese F-15 And C-130 Flight Line Crews Exposed To Jet Fuel Volatile Organic Compounds And Aerosols, Nicholas J. Delraso, David Mattie, Asao Kobayashi, Stephen W. Mitchell, Scott Dillard, Michael L. Raymer, Isaie Sibomana, Nicholas V. Reo

Computer Science and Engineering Faculty Publications

Air and ground crews transfer a significant amount of jet fuel, and as a result of transfers, breathe its volatile emission from residues. Working on the flight line also exposes maintainers to exhaust from the jet fuel as engines are tested or run before and after flight. Since little is known concerning level of exposure and the corresponding biological response associated with human jet fuel exposure, nuclear magnetic resonance (NMR)-based metabolomics analysis of human urine was utilized for characterization of metabolite profiles of flight line personnel for potential biomarker discovery. This project was a collaborative research effort between the US …


Is Your Ontology As Hard As You Think? Rewriting Ontologies Into Simpler Dls, David Carral, Cristina Feier, Ana Armas Romero, Bernardo Cuenca-Grau, Pascal Hitzler, Ian Horrocks Jul 2014

Is Your Ontology As Hard As You Think? Rewriting Ontologies Into Simpler Dls, David Carral, Cristina Feier, Ana Armas Romero, Bernardo Cuenca-Grau, Pascal Hitzler, Ian Horrocks

Computer Science and Engineering Faculty Publications

We investigate cases where an ontology expressed in a seemingly hard DL can be polynomially reduced to one in a simpler logic, while preserving reasoning outcomes for classification and fact entailment. Our transformations target the elimination of inverse roles, universal and existential restrictions, and in the best case allow us to rewrite the given ontology into one of the OWL 2 profiles. Even if an ontology cannot be fully rewritten into a profile, in many cases our transformations allow us to exploit further optimisation techniques. Moreover, the elimination of some out-of-profile axioms can improve the performance of modular reasoners, such …


El-Ifying Ontologies, David Carral, Cristina Feier, Bernardo Cuenca Grau, Pascal Hitzler, Ian Horrocks Jul 2014

El-Ifying Ontologies, David Carral, Cristina Feier, Bernardo Cuenca Grau, Pascal Hitzler, Ian Horrocks

Computer Science and Engineering Faculty Publications

The OWL 2 profiles are fragments of the ontology language OWL 2 for which standard reasoning tasks are feasible in polynomial time. Many OWL ontologies, however, contain a typically small number of out-of-profile axioms, which may have little or no influence on reasoning outcomes. We investigate techniques for rewriting axioms into the EL and RL profiles of OWL 2. We have tested our techniques on both classification and data reasoning tasks with encouraging results.


Accurate Local Estimation Of Geo-Coordinates For Social Media Posts, Derek Doran, Swapna S. Gokhale, Aldo Dagnino Jul 2014

Accurate Local Estimation Of Geo-Coordinates For Social Media Posts, Derek Doran, Swapna S. Gokhale, Aldo Dagnino

Computer Science and Engineering Faculty Publications

Associating geo-coordinates with the content of social media posts can enhance many existing applications and services and enable a host of new ones. Unfortunately, a majority of social media posts are not tagged with geo-coordinates. Even when location data is available, it may be inaccurate, very broad or sometimes fictitious. Contemporary location estimation approaches based on analyzing the content of these posts can identify only broad areas such as a city, which limits their usefulness. To address these shortcomings, this paper proposes a methodology to narrowly estimate the geo-coordinates of social media posts with high accuracy. The methodology relies solely …


Visualization Support For Cognitive Sciences, Matt J. Marangoni, Thomas Wischgoll, Yue Zhou, Leslie M. Blaha, Ross Smith, Rhonda J. Vickery May 2014

Visualization Support For Cognitive Sciences, Matt J. Marangoni, Thomas Wischgoll, Yue Zhou, Leslie M. Blaha, Ross Smith, Rhonda J. Vickery

Computer Science and Engineering Faculty Publications

The science of computer graphics and visualization is intertwined in many ways with Cognitive Sciences. On the one hand, computer graphics can lead to virtual environments in which a person is exposed to a virtual scenario. Typically, 3D-capable display technology combined with tracking systems, which are capable of identifying where the person is located at, are deployed to achieve maximal immersion in that the persons point of view is recreated in the virtual scenario. As a result, an impressive experience is created such that that person is navigating the virtual scenario as if it was real. On the other hand, …


A Practical Guide To An Fmri Experiment, Nasser H. Kashou May 2014

A Practical Guide To An Fmri Experiment, Nasser H. Kashou

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Functional Magnetic Resonance Imaging (fMRI) has been around for two decades and research in this field has been exponentially rising. Much of this research has been dominated by basic science. Recent trends have brought the clinical realm into play in which valuable contributions can still be made. Helping the clinician understand the basic concepts behind an fMRI experiment is crucial to further developing and evaluating functional paradigms and research. Critical to designing an fMRI experiment is understanding the related physics and how fine tuning scanning parameters affects the image quality, which in turn affect the findings of an fMRI study. …


Ivus Validation Of Patient Coronary Artery Lumen Area Obtained From Ct Images, Tong Luo, Thomas Wischgoll, Bon Kwon Koo, Yunlong Huo, Ghassan S. Kassab Jan 2014

Ivus Validation Of Patient Coronary Artery Lumen Area Obtained From Ct Images, Tong Luo, Thomas Wischgoll, Bon Kwon Koo, Yunlong Huo, Ghassan S. Kassab

Computer Science and Engineering Faculty Publications

Aims

Accurate computed tomography (CT)-based reconstruction of coronary morphometry (diameters, length, bifurcation angles) is important for construction of patient-specific models to aid diagnosis and therapy. The objective of this study is to validate the accuracy of patient coronary artery lumen area obtained from CT images based on intravascular ultrasound (IVUS).

Methods and Results

Morphometric data of 5 patient CT scans with 11 arteries from IVUS were reconstructed including the lumen cross sectional area (CSA), diameter and length. The volumetric data from CT images were analyzed at sub-pixel accuracy to obtain accurate vessel center lines and CSA. A new center line …


Dynamical Heterogeneity In Periodically Deformed Polymer Glasses, Nikolai V. Priezjev Jan 2014

Dynamical Heterogeneity In Periodically Deformed Polymer Glasses, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The dynamics of structural relaxation in a model polymer glass subject to spatially homogeneous, time-periodic shear deformation is investigated using molecular dynamics simulations. We study a coarse-grained bead-spring model of short polymer chains below the glass transition temperature. It is found that at small strain amplitudes, the segmental dynamics is nearly reversible over about 104 cycles, while at strain amplitudes above a few percent, polymer chains become fully relaxed after a hundred cycles. At the critical strain amplitude, the transition from slow to fast relaxation dynamics is associated with the largest number of dynamically correlated monomers as indicated by the …


Ontology Design Patterns For Ocean Science Data Discovery, Pascal Hitzler Jan 2014

Ontology Design Patterns For Ocean Science Data Discovery, Pascal Hitzler

Computer Science and Engineering Faculty Publications

No abstract provided.


Why The Data Train Needs Semantic Rails, Krzysztof Janowicz, Frank Van Harmelen, James A. Hendler, Pascal Hitzler Jan 2014

Why The Data Train Needs Semantic Rails, Krzysztof Janowicz, Frank Van Harmelen, James A. Hendler, Pascal Hitzler

Computer Science and Engineering Faculty Publications

While catchphrases such as big data, smart data, data intensive science, or smart dust highlight different aspects, they share a common theme: Namely, a shift towards a data-centric perspective in which the synthesis and analysis of data at an ever-increasing spatial, temporal, and thematic resolution promises new insights, while, at the same time, reducing the need for strong domain theories as starting points. In terms of the envisioned methodologies, those catchphrases tend to emphasize the role of predictive analytics, i.e., statistical techniques including data mining and machine learning, as well as supercomputing. Interestingly, however, while this perspective takes the availability …


An Ontology Pattern For Oceanographic Cruises: Towards An Oceanographer's Dream Of Integrated Knowledge Discovery, Adila Krisnadhi, Robert Arko, Suzanne Carbotte, Cynthia Chandler, Michelle Cheatham, Timothy Finin, Pascal Hitzler, Krzysztof Janowicz, Thomas Narock, Lisa Raymond, Adam Shepherd, Peter Wiebe Jan 2014

An Ontology Pattern For Oceanographic Cruises: Towards An Oceanographer's Dream Of Integrated Knowledge Discovery, Adila Krisnadhi, Robert Arko, Suzanne Carbotte, Cynthia Chandler, Michelle Cheatham, Timothy Finin, Pascal Hitzler, Krzysztof Janowicz, Thomas Narock, Lisa Raymond, Adam Shepherd, Peter Wiebe

Computer Science and Engineering Faculty Publications

EarthCube is a major effort of the National Science Foundation to establish a next-generation knowledge architecture for the broader geosciences. Data storage, retrieval, access, and reuse are central parts of this new effort. Currently, EarthCube is organized around several building blocks and research coordination networks. OceanLink is a semantics enabled building block that aims at improving data retrieval and reuse via ontologies, Semantic Web technologies, and Linked Data for the ocean sciences. Cruises, in the sense of research expeditions, are central events for ocean scientists. Consequently, information about these cruises and the involved vessels has to be shared and made …