Science.gov

Sample records for online model server

  1. Web-accessible molecular modeling with Rosetta: The Rosetta Online Server That Includes Everyone (ROSIE).

    PubMed

    Moretti, Rocco; Lyskov, Sergey; Das, Rhiju; Meiler, Jens; Gray, Jeffrey J

    2017-09-28

    The Rosetta molecular modeling software package provides a large number of experimentally validated tools for modeling and designing proteins, nucleic acids, and other biopolymers, with new protocols being added continually. While freely available to academic users, external usage is limited by the need for expertise in the Unix command line environment. To make Rosetta protocols available to a wider audience, we previously created a web server called ROSIE (Rosetta Online Server that Includes Everyone), which provides a common environment for hosting web-accessible Rosetta protocols. Here we describe a simplification of the ROSIE protocol specification format, one that permits easier implementation of Rosetta protocols. Whereas the previous format required creating multiple separate files in different locations, the new format allows specification of the protocol in a single file. This new, simplified protocol specification has more than doubled the number of Rosetta protocols available under ROSIE. These new applications include pKa determination, lipid accessibility calculation, RNA redesign, protein-protein docking, protein-small molecule docking, symmetric docking, antibody docking, cyclic toxin docking, critical binding peptide determination, and mapping small molecule binding sites. ROSIE is freely available to academic users at http://rosie.rosettacommons.org. This article is protected by copyright. All rights reserved. © 2017 The Protein Society.

  2. Serverification of Molecular Modeling Applications: The Rosetta Online Server That Includes Everyone (ROSIE)

    PubMed Central

    Conchúir, Shane Ó.; Der, Bryan S.; Drew, Kevin; Kuroda, Daisuke; Xu, Jianqing; Weitzner, Brian D.; Renfrew, P. Douglas; Sripakdeevong, Parin; Borgo, Benjamin; Havranek, James J.; Kuhlman, Brian; Kortemme, Tanja; Bonneau, Richard; Gray, Jeffrey J.; Das, Rhiju

    2013-01-01

    The Rosetta molecular modeling software package provides experimentally tested and rapidly evolving tools for the 3D structure prediction and high-resolution design of proteins, nucleic acids, and a growing number of non-natural polymers. Despite its free availability to academic users and improving documentation, use of Rosetta has largely remained confined to developers and their immediate collaborators due to the code’s difficulty of use, the requirement for large computational resources, and the unavailability of servers for most of the Rosetta applications. Here, we present a unified web framework for Rosetta applications called ROSIE (Rosetta Online Server that Includes Everyone). ROSIE provides (a) a common user interface for Rosetta protocols, (b) a stable application programming interface for developers to add additional protocols, (c) a flexible back-end to allow leveraging of computer cluster resources shared by RosettaCommons member institutions, and (d) centralized administration by the RosettaCommons to ensure continuous maintenance. This paper describes the ROSIE server infrastructure, a step-by-step ‘serverification’ protocol for use by Rosetta developers, and the deployment of the first nine ROSIE applications by six separate developer teams: Docking, RNA de novo, ERRASER, Antibody, Sequence Tolerance, Supercharge, Beta peptide design, NCBB design, and VIP redesign. As illustrated by the number and diversity of these applications, ROSIE offers a general and speedy paradigm for serverification of Rosetta applications that incurs negligible cost to developers and lowers barriers to Rosetta use for the broader biological community. ROSIE is available at http://rosie.rosettacommons.org. PMID:23717507

  3. ModelTest Server: a web-based tool for the statistical selection of models of nucleotide substitution online.

    PubMed

    Posada, David

    2006-07-01

    ModelTest server is a web-based application for the selection of models of nucleotide substitution using the program ModelTest. The server takes as input a text file with likelihood scores for the set of candidate models. Models can be selected with hierarchical likelihood ratio tests, or with the Akaike or Bayesian information criteria. The output includes several statistics for the assessment of model selection uncertainty, for model averaging or to estimate the relative importance of model parameters. The server can be accessed at http://darwin.uvigo.es/software/modeltest_server.html.

  4. ModelTest Server: a web-based tool for the statistical selection of models of nucleotide substitution online

    PubMed Central

    Posada, David

    2006-01-01

    ModelTest server is a web-based application for the selection of models of nucleotide substitution using the program ModelTest. The server takes as input a text file with likelihood scores for the set of candidate models. Models can be selected with hierarchical likelihood ratio tests, or with the Akaike or Bayesian information criteria. The output includes several statistics for the assessment of model selection uncertainty, for model averaging or to estimate the relative importance of model parameters. The server can be accessed at . PMID:16845102

  5. Network characteristics for server selection in online games

    NASA Astrophysics Data System (ADS)

    Claypool, Mark

    2008-01-01

    Online gameplay is impacted by the network characteristics of players connected to the same server. Unfortunately, the network characteristics of online game servers are not well-understood, particularly for groups that wish to play together on the same server. As a step towards a remedy, this paper presents analysis of an extensive set of measurements of game servers on the Internet. Over the course of many months, actual Internet game servers were queried simultaneously by twenty-five emulated game clients, with both servers and clients spread out on the Internet. The data provides statistics on the uptime and populations of game servers over a month long period an an in-depth look at the suitability for game servers for multi-player server selection, concentrating on characteristics critical to playability--latency and fairness. Analysis finds most game servers have latencies suitable for third-person and omnipresent games, such as real-time strategy, sports and role-playing games, providing numerous server choices for game players. However, far fewer game servers have the low latencies required for first-person games, such as shooters or race games. In all cases, groups that wish to play together have a greatly reduced set of servers from which to choose because of inherent unfairness in server latencies and server selection is particularly limited as the group size increases. These results hold across different game types and even across different generations of games. The data should be useful for game developers and network researchers that seek to improve game server selection, whether for single or multiple players.

  6. Design of Accelerator Online Simulator Server Using Structured Data

    SciTech Connect

    Shen, Guobao; Chu, Chungming; Wu, Juhao; Kraimer, Martin; /Argonne

    2012-07-06

    Model based control plays an important role for a modern accelerator during beam commissioning, beam study, and even daily operation. With a realistic model, beam behaviour can be predicted and therefore effectively controlled. The approach used by most current high level application environments is to use a built-in simulation engine and feed a realistic model into that simulation engine. Instead of this traditional monolithic structure, a new approach using a client-server architecture is under development. An on-line simulator server is accessed via network accessible structured data. With this approach, a user can easily access multiple simulation codes. This paper describes the design, implementation, and current status of PVData, which defines the structured data, and PVAccess, which provides network access to the structured data.

  7. RCD+: Fast loop modeling server.

    PubMed

    López-Blanco, José Ramón; Canosa-Valls, Alejandro Jesús; Li, Yaohang; Chacón, Pablo

    2016-07-08

    Modeling loops is a critical and challenging step in protein modeling and prediction. We have developed a quick online service (http://rcd.chaconlab.org) for ab initio loop modeling combining a coarse-grained conformational search with a full-atom refinement. Our original Random Coordinate Descent (RCD) loop closure algorithm has been greatly improved to enrich the sampling distribution towards near-native conformations. These improvements include a new workflow optimization, MPI-parallelization and fast backbone angle sampling based on neighbor-dependent Ramachandran probability distributions. The server starts by efficiently searching the vast conformational space from only the loop sequence information and the environment atomic coordinates. The generated closed loop models are subsequently ranked using a fast distance-orientation dependent energy filter. Top ranked loops are refined with the Rosetta energy function to obtain accurate all-atom predictions that can be interactively inspected in an user-friendly web interface. Using standard benchmarks, the average root mean squared deviation (RMSD) is 0.8 and 1.4 Å for 8 and 12 residues loops, respectively, in the challenging modeling scenario in where the side chains of the loop environment are fully remodeled. These results are not only very competitive compared to those obtained with public state of the art methods, but also they are obtained ∼10-fold faster. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  8. RCD+: Fast loop modeling server

    PubMed Central

    López-Blanco, José Ramón; Canosa-Valls, Alejandro Jesús; Li, Yaohang; Chacón, Pablo

    2016-01-01

    Modeling loops is a critical and challenging step in protein modeling and prediction. We have developed a quick online service (http://rcd.chaconlab.org) for ab initio loop modeling combining a coarse-grained conformational search with a full-atom refinement. Our original Random Coordinate Descent (RCD) loop closure algorithm has been greatly improved to enrich the sampling distribution towards near-native conformations. These improvements include a new workflow optimization, MPI-parallelization and fast backbone angle sampling based on neighbor-dependent Ramachandran probability distributions. The server starts by efficiently searching the vast conformational space from only the loop sequence information and the environment atomic coordinates. The generated closed loop models are subsequently ranked using a fast distance-orientation dependent energy filter. Top ranked loops are refined with the Rosetta energy function to obtain accurate all-atom predictions that can be interactively inspected in an user-friendly web interface. Using standard benchmarks, the average root mean squared deviation (RMSD) is 0.8 and 1.4 Å for 8 and 12 residues loops, respectively, in the challenging modeling scenario in where the side chains of the loop environment are fully remodeled. These results are not only very competitive compared to those obtained with public state of the art methods, but also they are obtained ∼10-fold faster. PMID:27151199

  9. A Scalability Model for ECS's Data Server

    NASA Technical Reports Server (NTRS)

    Menasce, Daniel A.; Singhal, Mukesh

    1998-01-01

    This report presents in four chapters a model for the scalability analysis of the Data Server subsystem of the Earth Observing System Data and Information System (EOSDIS) Core System (ECS). The model analyzes if the planned architecture of the Data Server will support an increase in the workload with the possible upgrade and/or addition of processors, storage subsystems, and networks. The approaches in the report include a summary of the architecture of ECS's Data server as well as a high level description of the Ingest and Retrieval operations as they relate to ECS's Data Server. This description forms the basis for the development of the scalability model of the data server and the methodology used to solve it.

  10. SWISS-MODEL: an automated protein homology-modeling server

    PubMed Central

    Schwede, Torsten; Kopp, Jürgen; Guex, Nicolas; Peitsch, Manuel C.

    2003-01-01

    SWISS-MODEL (http://swissmodel.expasy.org) is a server for automated comparative modeling of three-dimensional (3D) protein structures. It pioneered the field of automated modeling starting in 1993 and is the most widely-used free web-based automated modeling facility today. In 2002 the server computed 120 000 user requests for 3D protein models. SWISS-MODEL provides several levels of user interaction through its World Wide Web interface: in the ‘first approach mode’ only an amino acid sequence of a protein is submitted to build a 3D model. Template selection, alignment and model building are done completely automated by the server. In the ‘alignment mode’, the modeling process is based on a user-defined target-template alignment. Complex modeling tasks can be handled with the ‘project mode’ using DeepView (Swiss-PdbViewer), an integrated sequence-to-structure workbench. All models are sent back via email with a detailed modeling report. WhatCheck analyses and ANOLEA evaluations are provided optionally. The reliability of SWISS-MODEL is continuously evaluated in the EVA-CM project. The SWISS-MODEL server is under constant development to improve the successful implementation of expert knowledge into an easy-to-use server. PMID:12824332

  11. PlanetServer: Innovative approaches for the online analysis of hyperspectral satellite data from Mars

    NASA Astrophysics Data System (ADS)

    Oosthoek, J. H. P.; Flahaut, J.; Rossi, A. P.; Baumann, P.; Misev, D.; Campalani, P.; Unnithan, V.

    2014-06-01

    PlanetServer is a WebGIS system, currently under development, enabling the online analysis of Compact Reconnaissance Imaging Spectrometer (CRISM) hyperspectral data from Mars. It is part of the EarthServer project which builds infrastructure for online access and analysis of huge Earth Science datasets. Core functionality consists of the rasdaman Array Database Management System (DBMS) for storage, and the Open Geospatial Consortium (OGC) Web Coverage Processing Service (WCPS) for data querying. Various WCPS queries have been designed to access spatial and spectral subsets of the CRISM data. The client WebGIS, consisting mainly of the OpenLayers javascript library, uses these queries to enable online spatial and spectral analysis. Currently the PlanetServer demonstration consists of two CRISM Full Resolution Target (FRT) observations, surrounding the NASA Curiosity rover landing site. A detailed analysis of one of these observations is performed in the Case Study section. The current PlanetServer functionality is described step by step, and is tested by focusing on detecting mineralogical evidence described in earlier Gale crater studies. Both the PlanetServer methodology and its possible use for mineralogical studies will be further discussed. Future work includes batch ingestion of CRISM data and further development of the WebGIS and analysis tools.

  12. "Just Another Tool for Online Studies" (JATOS): An Easy Solution for Setup and Management of Web Servers Supporting Online Studies.

    PubMed

    Lange, Kristian; Kühn, Simone; Filevich, Elisa

    2015-01-01

    We present here "Just Another Tool for Online Studies" (JATOS): an open source, cross-platform web application with a graphical user interface (GUI) that greatly simplifies setting up and communicating with a web server to host online studies that are written in JavaScript. JATOS is easy to install in all three major platforms (Microsoft Windows, Mac OS X, and Linux), and seamlessly pairs with a database for secure data storage. It can be installed on a server or locally, allowing researchers to try the application and feasibility of their studies within a browser environment, before engaging in setting up a server. All communication with the JATOS server takes place via a GUI (with no need to use a command line interface), making JATOS an especially accessible tool for researchers without a strong IT background. We describe JATOS' main features and implementation and provide a detailed tutorial along with example studies to help interested researchers to set up their online studies. JATOS can be found under the Internet address: www.jatos.org.

  13. "Just Another Tool for Online Studies” (JATOS): An Easy Solution for Setup and Management of Web Servers Supporting Online Studies

    PubMed Central

    Lange, Kristian; Kühn, Simone; Filevich, Elisa

    2015-01-01

    We present here “Just Another Tool for Online Studies” (JATOS): an open source, cross-platform web application with a graphical user interface (GUI) that greatly simplifies setting up and communicating with a web server to host online studies that are written in JavaScript. JATOS is easy to install in all three major platforms (Microsoft Windows, Mac OS X, and Linux), and seamlessly pairs with a database for secure data storage. It can be installed on a server or locally, allowing researchers to try the application and feasibility of their studies within a browser environment, before engaging in setting up a server. All communication with the JATOS server takes place via a GUI (with no need to use a command line interface), making JATOS an especially accessible tool for researchers without a strong IT background. We describe JATOS’ main features and implementation and provide a detailed tutorial along with example studies to help interested researchers to set up their online studies. JATOS can be found under the Internet address: www.jatos.org. PMID:26114751

  14. GrayStarServer: Stellar atmospheric modeling and spectrum synthesis

    NASA Astrophysics Data System (ADS)

    Short, C. Ian

    2017-01-01

    GrayStarServer is a stellar atmospheric modeling and spectrum synthesis code of pedagogical accuracy that is accessible in any web browser on commonplace computational devices and that runs on a timescale of a few seconds.

  15. MO/DSD online information server and global information repository access

    NASA Technical Reports Server (NTRS)

    Nguyen, Diem; Ghaffarian, Kam; Hogie, Keith; Mackey, William

    1994-01-01

    Often in the past, standards and new technology information have been available only in hardcopy form, with reproduction and mailing costs proving rather significant. In light of NASA's current budget constraints and in the interest of efficient communications, the Mission Operations and Data Systems Directorate (MO&DSD) New Technology and Data Standards Office recognizes the need for an online information server (OLIS). This server would allow: (1) dissemination of standards and new technology information throughout the Directorate more quickly and economically; (2) online browsing and retrieval of documents that have been published for and by MO&DSD; and (3) searching for current and past study activities on related topics within NASA before issuing a task. This paper explores a variety of available information servers and searching tools, their current capabilities and limitations, and the application of these tools to MO&DSD. Most importantly, the discussion focuses on the way this concept could be easily applied toward improving dissemination of standards and new technologies and improving documentation processes.

  16. Telematics-based online client-server/client collaborative environment for radiotherapy planning simulations.

    PubMed

    Kum, Oyeon

    2007-11-01

    Customized cancer radiation treatment planning for each patient is very useful for both a patient and a doctor because it provides the ability to deliver higher doses to a more accurately defined tumor and at the same time lower doses to organs at risk and normal tissues. This can be realized by building an accurate planning simulation system to provide better treatment strategies based on each patient's tomographic data such as CT, MRI, PET, or SPECT. In this study, we develop a real-time online client-server/client collaborative environment between the client (health care professionals or hospitals) and the server/client under a secure network using telematics (the integrated use of telecommunications and medical informatics). The implementation is based on a point-to-point communication scheme between client and server/client following the WYSIWIS (what you see is what I see) paradigm. After uploading the patient tomographic data, the client is able to collaborate with the server/client for treatment planning. Consequently, the level of health care services can be improved, specifically for small radiotherapy clinics in rural/remote-country areas that do not possess much experience or equipment such as a treatment planning simulator. The telematics service of the system can also be used to provide continued medical education in radiotherapy. Moreover, the system is easy to use. A client can use the system if s/he is familiar with the Windows(TM) operating system because it is designed and built based on a user-friendly concept. This system does not require the client to continue hardware and software maintenance and updates. These are performed automatically by the server.

  17. Client/server models for transparent, distributed computational resources

    SciTech Connect

    Hammer, K.E.; Gilman, T.L.

    1991-01-01

    Client/server models are proposed to address issues of shared resources in a distributed, heterogeneous UNIX environment. Recent development of automated Remote Procedure Call (RPC) interface generator has simplified the development of client/server models. Previously, implementation of the models was only possible at the UNIX socket level. An overview of RPCs and the interface generator will be presented and will include a discussion of generation and installation of remote services, the RPC paradigm, and the three levels of RPC programming. Two applications, the Nuclear Plant Analyzer (NPA) and a fluids simulation using molecular modelling, will be presented to demonstrate how client/server models using RPCs and External Data Representations (XDR) have been used production/computation situations. The NPA incorporates a client/server interface for transferring/translation of TRAC or RELAP results from the UNICOS Cray to a UNIX workstation. The fluids simulation program utilizes the client/server model to access the Cray via a single function allowing it to become a shared co-processor to the workstation application. 5 refs., 6 figs.

  18. Parmodel: a web server for automated comparative modeling of proteins.

    PubMed

    Uchôa, Hugo Brandão; Jorge, Guilherme Eberhart; Freitas Da Silveira, Nelson José; Camera, João Carlos; Canduri, Fernanda; De Azevedo, Walter Filgueira

    2004-12-24

    Parmodel is a web server for automated comparative modeling and evaluation of protein structures. The aim of this tool is to help inexperienced users to perform modeling, assessment, visualization, and optimization of protein models as well as crystallographers to evaluate structures solved experimentally. It is subdivided in four modules: Parmodel Modeling, Parmodel Assessment, Parmodel Visualization, and Parmodel Optimization. The main module is the Parmodel Modeling that allows the building of several models for a same protein in a reduced time, through the distribution of modeling processes on a Beowulf cluster. Parmodel automates and integrates the main softwares used in comparative modeling as MODELLER, Whatcheck, Procheck, Raster3D, Molscript, and Gromacs. This web server is freely accessible at .

  19. 3D-DART: a DNA structure modelling server

    PubMed Central

    van Dijk, Marc; Bonvin, Alexandre M. J. J.

    2009-01-01

    There is a growing interest in structural studies of DNA by both experimental and computational approaches. Often, 3D-structural models of DNA are required, for instance, to serve as templates for homology modeling, as starting structures for macro-molecular docking or as scaffold for NMR structure calculations. The conformational adaptability of DNA when binding to a protein is often an important factor and at the same time a limitation in such studies. As a response to the demand for 3D-structural models reflecting the intrinsic plasticity of DNA we present the 3D-DART server (3DNA-Driven DNA Analysis and Rebuilding Tool). The server provides an easy interface to a powerful collection of tools for the generation of DNA-structural models in custom conformations. The computational engine beyond the server makes use of the 3DNA software suite together with a collection of home-written python scripts. The server is freely available at http://haddock.chem.uu.nl/dna without any login requirement. PMID:19417072

  20. Group-oriented coordination models for distributed client-server computing

    NASA Technical Reports Server (NTRS)

    Adler, Richard M.; Hughes, Craig S.

    1994-01-01

    This paper describes group-oriented control models for distributed client-server interactions. These models transparently coordinate requests for services that involve multiple servers, such as queries across distributed databases. Specific capabilities include: decomposing and replicating client requests; dispatching request subtasks or copies to independent, networked servers; and combining server results into a single response for the client. The control models were implemented by combining request broker and process group technologies with an object-oriented communication middleware tool. The models are illustrated in the context of a distributed operations support application for space-based systems.

  1. A Predictive Performance Model to Evaluate the Contention Cost in Application Servers

    SciTech Connect

    Chen, Shiping; Gorton, Ian )

    2002-12-04

    In multi-tier enterprise systems, application servers are key components that implement business logic and provide application services. To support a large number of simultaneous accesses from clients over the Internet and intranet, most application servers use replication and multi-threading to handle concurrent requests. While multiple processes and multiple threads enhance the processing bandwidth of servers, they also increase the contention for resources in application servers. This paper investigates this issue empirically based on a middleware benchmark. A cost model is proposed to estimate the overall performance of application servers, including the contention overhead. This model is then used to determine the optimal degree of the concurrency of application servers for a specific client load. A case study based on CORBA is presented to validate our model and demonstrate its application.

  2. SciServer: An Online Collaborative Environment for Big Data in Research and Education

    NASA Astrophysics Data System (ADS)

    Raddick, Jordan; Souter, Barbara; Lemson, Gerard; Taghizadeh-Popp, Manuchehr

    2017-01-01

    For the past year, SciServer Compute (http://compute.sciserver.org) has offered access to big data resources running within server-side Docker containers. Compute has allowed thousands of researchers to bring advanced analysis to big datasets like the Sloan Digital Sky Survey and others, while keeping the analysis close to the data for better performance and easier read/write access. SciServer Compute is just one part of the SciServer system being developed at Johns Hopkins University, which provides an easy-to-use collaborative research environment for astronomy and many other sciences.SciServer enables these collaborative research strategies using Jupyter notebooks, in which users can write their own Python and R scripts and execute them on the same server as the data. We have written special-purpose libraries for querying, reading, and writing data. Intermediate results can be stored in large scratch space (hundreds of TBs) and analyzed directly from within Python or R with state-of-the-art visualization and machine learning libraries. Users can store science-ready results in their permanent allocation on SciDrive, a Dropbox-like system for sharing and publishing files.SciServer Compute’s virtual research environment has grown with the addition of task management and access control functions, allowing collaborators to share both data and analysis scripts securely across the world. These features also open up new possibilities for education, allowing instructors to share datasets with students and students to write analysis scripts to share with their instructors. We are leveraging these features into a new system called “SciServer Courseware,” which will allow instructors to share assignments with their students, allowing students to engage with big data in new ways.SciServer has also expanded to include more datasets beyond the Sloan Digital Sky Survey. A part of that growth has been the addition of the SkyQuery component, which allows for simple, fast

  3. TJ-II data retrieving by means of a client/server model

    NASA Astrophysics Data System (ADS)

    Vega, J.; Sánchez, E.; Crémy, C.; Portas, A.; Dulya, C. M.; Nilsson, J.

    1999-01-01

    The database of the TJ-II flexible heliac is centralized in a Unix server. This computer also commands the on-line processes related to data acquisition during TJ-II discharges: programming of measurement systems, connectivity with control systems, data visualization, and computations. The server has to provide access to the data so that signal analysis can be performed by local users or even from remote hosts. Data retrieving is accomplished by means of a client/server architecture in which two data servers are permanently running in the background of the Unix computer. One of them serves data requests from local clients and the other one sends data to remote clients. The communication protocol in both cases has been developed by using TCP/IP and Berkeley sockets. The client part consists of a set of routines (FORTRAN and C callable), which, in a transparent way, provide connectivity with the servers. This structure allows access to TJ-II data exactly in the same way from any computer, hiding not only specific aspects of the database, but hardware architecture of the server computer as well. In addition, the remote access makes it possible to distribute computations and to reduce the load on the Unix server from analysis and visualization tasks. At present, this software is running in four different environments: the Unix server itself, various types of Unix workstations, a CRAY J90 and a CRAY T3E. Finally, due to the fact that visualization is essential for TJ-II data analysis, a powerful and a very flexible visualization tool has been developed. It is a point and click application based on X Window/Motif. Data access is carried out through the client/server processes mentioned above and the software runs in the client computer.

  4. Real-Time Robust Adaptive Modeling and Scheduling for an Electronic Commerce Server

    NASA Astrophysics Data System (ADS)

    Du, Bing; Ruan, Chun

    With the increasing importance and pervasiveness of Internet services, it is becoming a challenge for the proliferation of electronic commerce services to provide performance guarantees under extreme overload. This paper describes a real-time optimization modeling and scheduling approach for performance guarantee of electronic commerce servers. We show that an electronic commerce server may be simulated as a multi-tank system. A robust adaptive server model is subject to unknown additive load disturbances and uncertain model matching. Overload control techniques are based on adaptive admission control to achieve timing guarantees. We evaluate the performance of the model using a complex simulation that is subjected to varying model parameters and massive overload.

  5. Online Collaboration: Two Models.

    ERIC Educational Resources Information Center

    Espinoza, Sue; McKinzie, LeAnn

    This paper describes two collaborative projects conducted with graduate students from Texas A&M University-Commerce and West Texas A&M University during the fall semesters of 1997 and 1998. The instructors, with a history of personal collaboration both in person and online, designed an activity to provide their graduate students with the…

  6. Performance model of the Argonne Voyager multimedia server

    SciTech Connect

    Disz, T.; Olson, R.; Stevens, R.

    1997-07-01

    The Argonne Voyager Multimedia Server is being developed in the Futures Lab of the Mathematics and Computer Science Division at Argonne National Laboratory. As a network-based service for recording and playing multimedia streams, it is important that the Voyager system be capable of sustaining certain minimal levels of performance in order for it to be a viable system. In this article, the authors examine the performance characteristics of the server. As they examine the architecture of the system, they try to determine where bottlenecks lie, show actual vs potential performance, and recommend areas for improvement through custom architectures and system tuning.

  7. RHIC injector complex online model status and plans

    SciTech Connect

    Schoefer,V.; Ahrens, L.; Brown, K.; Morris, J.; Nemesure, S.

    2009-05-04

    An online modeling system is being developed for the RHIC injector complex, which consists of the Booster, the AGS and the transfer lines connecting the Booster to the AGS and the AGS to RHIC. Historically the injectors have been operated using static values from design specifications or offline model runs, but tighter beam optics constraints required by polarized proton operations (e.g, accelerating with near-integer tunes) have necessitated a more dynamic system. An online model server for the AGS has been implemented using MAD-X [1] as the model engine, with plans to extend the system to the Booster and the injector transfer lines and to add the option of calculating optics using the Polymorphic Tracking Code (PTC [2]) as the model engine.

  8. Cybersecurity, massive data processing, community interaction, and other developments at WWW-based computational X-ray Server

    NASA Astrophysics Data System (ADS)

    Stepanov, Sergey

    2013-03-01

    X-Ray Server (x-server.gmca.aps.anl.gov) is a WWW-based computational server for modeling of X-ray diffraction, reflection and scattering data. The modeling software operates directly on the server and can be accessed remotely either from web browsers or from user software. In the later case the server can be deployed as a software library or a data fitting engine. As the server recently surpassed the milestones of 15 years online and 1.5 million calculations, it accumulated a number of technical solutions that are discussed in this paper. The developed approaches to detecting physical model limits and user calculations failures, solutions to spam and firewall problems, ways to involve the community in replenishing databases and methods to teach users automated access to the server programs may be helpful for X-ray researchers interested in using the server or sharing their own software online.

  9. Impact of malicious servers over trust and reputation models in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Verma, Vinod Kumar; Singh, Surinder; Pathak, N. P.

    2016-03-01

    This article deals with the impact of malicious servers over different trust and reputation models in wireless sensor networks. First, we analysed the five trust and reputation models, namely BTRM-WSN, Eigen trust, peer trust, power trust, linguistic fuzzy trust model. Further, we proposed wireless sensor network design for optimisation of these models. Finally, influence of malicious servers on the behaviour of above mentioned trust and reputation models is discussed. Statistical analysis has been carried out to prove the validity of our proposal.

  10. A distributed clients/distributed servers model for STARCAT

    NASA Technical Reports Server (NTRS)

    Pirenne, B.; Albrecht, M. A.; Durand, D.; Gaudet, S.

    1992-01-01

    STARCAT, the Space Telescope ARchive and CATalogue user interface has been along for a number of years already. During this time it has been enhanced and augmented in a number of different fields. This time, we would like to dwell on a new capability allowing geographically distributed user interfaces to connect to geographically distributed data servers. This new concept permits users anywhere on the internet running STARCAT on their local hardware to access e.g., whichever of the 3 existing HST archive sites is available, or get information on the CFHT archive through a transparent connection to the CADC in BC or to get the La Silla weather by connecting to the ESO database in Munich during the same session. Similarly PreView (or quick look) images and spectra will also flow directly to the user from wherever it is available. Moving towards an 'X'-based STARCAT is another goal being pursued: a graphic/image server and a help/doc server are currently being added to it. They should further enhance the user independence and access transparency.

  11. Vacation model for Markov machine repair problem with two heterogeneous unreliable servers and threshold recovery

    NASA Astrophysics Data System (ADS)

    Jain, Madhu; Meena, Rakesh Kumar

    2017-06-01

    Markov model of multi-component machining system comprising two unreliable heterogeneous servers and mixed type of standby support has been studied. The repair job of broken down machines is done on the basis of bi-level threshold policy for the activation of the servers. The server returns back to render repair job when the pre-specified workload of failed machines is build up. The first (second) repairman turns on only when the work load of N1 (N2) failed machines is accumulated in the system. The both servers may go for vacation in case when all the machines are in good condition and there are no pending repair jobs for the repairmen. Runge-Kutta method is implemented to solve the set of governing equations used to formulate the Markov model. Various system metrics including the mean queue length, machine availability, throughput, etc., are derived to determine the performance of the machining system. To provide the computational tractability of the present investigation, a numerical illustration is provided. A cost function is also constructed to determine the optimal repair rate of the server by minimizing the expected cost incurred on the system. The hybrid soft computing method is considered to develop the adaptive neuro-fuzzy inference system (ANFIS). The validation of the numerical results obtained by Runge-Kutta approach is also facilitated by computational results generated by ANFIS.

  12. RNAKinetics: a web server that models secondary structure kinetics of an elongating RNA.

    PubMed

    Danilova, Ludmila V; Pervouchine, Dmitri D; Favorov, Alexander V; Mironov, Andrei A

    2006-04-01

    The RNAKinetics server (http://www.ig-msk.ru/RNA/kinetics) is a web interface for the newly developed RNAKinetics software. The software models the dynamics of RNA secondary structure by the means of kinetic analysis of folding transitions of a growing RNA molecule. The result of the modeling is a kinetic ensemble, i.e. a collection of RNA structures that are endowed with probabilities, which depend on time. This approach gives comprehensive probabilistic description of RNA folding pathways, revealing important kinetic details that are not captured by the traditional structure prediction methods. The access to the RNAKinetics server is free.

  13. viwish: a visualization server for protein modelling and docking.

    PubMed

    Klein, T; Ackermann, F; Posch, S

    1996-12-12

    A visualization tool viwish for proteins based on the Tcl command language has been developed. The system is completely menu driven and can display arbitrary many proteins in arbitrary many windows. It isinstantly t o use, even for non computer experts and provides possibilities to modify menus, configurations, and windows. It may be used as a stand-alone molecular graphics package or as a graphics server for external programs. Communications with these client applications is established even across different machines (through the send command to Tk, an extension of Tcl). In addition, a wide rage of chemical data like molecular surfaces and 3D gridded samplings of chemical features can be displayed. Therefore the systmen is especially useful for the development of algorithms that need visual distributed freely, including the source code.

  14. SEED Servers: High-Performance Access to the SEED Genomes, Annotations, and Metabolic Models

    PubMed Central

    Aziz, Ramy K.; Devoid, Scott; Disz, Terrence; Edwards, Robert A.; Henry, Christopher S.; Olsen, Gary J.; Olson, Robert; Overbeek, Ross; Parrello, Bruce; Pusch, Gordon D.; Stevens, Rick L.; Vonstein, Veronika; Xia, Fangfang

    2012-01-01

    The remarkable advance in sequencing technology and the rising interest in medical and environmental microbiology, biotechnology, and synthetic biology resulted in a deluge of published microbial genomes. Yet, genome annotation, comparison, and modeling remain a major bottleneck to the translation of sequence information into biological knowledge, hence computational analysis tools are continuously being developed for rapid genome annotation and interpretation. Among the earliest, most comprehensive resources for prokaryotic genome analysis, the SEED project, initiated in 2003 as an integration of genomic data and analysis tools, now contains >5,000 complete genomes, a constantly updated set of curated annotations embodied in a large and growing collection of encoded subsystems, a derived set of protein families, and hundreds of genome-scale metabolic models. Until recently, however, maintaining current copies of the SEED code and data at remote locations has been a pressing issue. To allow high-performance remote access to the SEED database, we developed the SEED Servers (http://www.theseed.org/servers): four network-based servers intended to expose the data in the underlying relational database, support basic annotation services, offer programmatic access to the capabilities of the RAST annotation server, and provide access to a growing collection of metabolic models that support flux balance analysis. The SEED servers offer open access to regularly updated data, the ability to annotate prokaryotic genomes, the ability to create metabolic reconstructions and detailed models of metabolism, and access to hundreds of existing metabolic models. This work offers and supports a framework upon which other groups can build independent research efforts. Large integrations of genomic data represent one of the major intellectual resources driving research in biology, and programmatic access to the SEED data will provide significant utility to a broad collection of potential

  15. SEED servers: high-performance access to the SEED genomes, annotations, and metabolic models.

    PubMed

    Aziz, Ramy K; Devoid, Scott; Disz, Terrence; Edwards, Robert A; Henry, Christopher S; Olsen, Gary J; Olson, Robert; Overbeek, Ross; Parrello, Bruce; Pusch, Gordon D; Stevens, Rick L; Vonstein, Veronika; Xia, Fangfang

    2012-01-01

    The remarkable advance in sequencing technology and the rising interest in medical and environmental microbiology, biotechnology, and synthetic biology resulted in a deluge of published microbial genomes. Yet, genome annotation, comparison, and modeling remain a major bottleneck to the translation of sequence information into biological knowledge, hence computational analysis tools are continuously being developed for rapid genome annotation and interpretation. Among the earliest, most comprehensive resources for prokaryotic genome analysis, the SEED project, initiated in 2003 as an integration of genomic data and analysis tools, now contains >5,000 complete genomes, a constantly updated set of curated annotations embodied in a large and growing collection of encoded subsystems, a derived set of protein families, and hundreds of genome-scale metabolic models. Until recently, however, maintaining current copies of the SEED code and data at remote locations has been a pressing issue. To allow high-performance remote access to the SEED database, we developed the SEED Servers (http://www.theseed.org/servers): four network-based servers intended to expose the data in the underlying relational database, support basic annotation services, offer programmatic access to the capabilities of the RAST annotation server, and provide access to a growing collection of metabolic models that support flux balance analysis. The SEED servers offer open access to regularly updated data, the ability to annotate prokaryotic genomes, the ability to create metabolic reconstructions and detailed models of metabolism, and access to hundreds of existing metabolic models. This work offers and supports a framework upon which other groups can build independent research efforts. Large integrations of genomic data represent one of the major intellectual resources driving research in biology, and programmatic access to the SEED data will provide significant utility to a broad collection of potential

  16. Serving Collections of Forecast Model Runs with the THREDDS Data Server

    NASA Astrophysics Data System (ADS)

    Caron, J.

    2006-12-01

    The THREDDS Data Server (TDS) is a web server that provides metadata and data access for scientific datasets. It provides OPeNDAP, WCS, HTTP and netCDF subsetting services for a number of data formats, including netCDF, HDF5, GRIB, BUFR, etc. The TDS is 100% Java, and runs within the Tomcat web server. We have added a new way to serve model data, which takes a collection of Forecast Model Run datasets, and constructs a single dataset with a 2D time coordinate (run time, forecast time). In the case of Unidata's server, these are collections of GRIB files, and we deal correctly with missing data records by using the forecast and run dates, rather than array indices. The TDS also creates various other "synthetic" datasets from the collection: 1) all data from one analysis run; 2) data with the same forecast offset hour (eg all the 3 hour forecasts, from different runs); 3) data with a constant forecast date (eg all the data with forecast/valid time of 2006-08-08T12:00:00Z, from different runs); and 4) the "best" time series, taking the data from the most recent run available. We are currently working with a number of data partners to test and extend this functionality.

  17. Empirical cost models for estimating power and energy consumption in database servers

    NASA Astrophysics Data System (ADS)

    Valdivia Garcia, Harold Dwight

    The explosive growth in the size of data centers, coupled with the widespread use of virtualization technology has brought power and energy consumption as major concerns for data center administrators. Provisioning decisions must take into consideration not only target application performance but also the power demands and total energy consumption incurred by the hardware and software to be deployed at the data center. Failure to do so will result in damaged equipment, power outages, and inefficient operation. Since database servers comprise one of the most popular and important server applications deployed in such facilities, it becomes necessary to have accurate cost models that can predict the power and energy demands that each database workloads will impose in the system. In this work we present an empirical methodology to estimate the power and energy cost of database operations. Our methodology uses multiple-linear regression to derive accurate cost models that depend only on readily available statistics such as selectivity factors, tuple size, numbers columns and relational cardinality. Moreover, our method does not need measurement of individual hardware components, but rather total power and energy consumption measured at a server. We have implemented our methodology, and ran experiments with several server configurations. Our experiments indicate that we can predict power and energy more accurately than alternative methods found in the literature.

  18. THttpServer class in ROOT

    NASA Astrophysics Data System (ADS)

    Adamczewski-Musch, Joern; Linev, Sergey

    2015-12-01

    The new THttpServer class in ROOT implements HTTP server for arbitrary ROOT applications. It is based on Civetweb embeddable HTTP server and provides direct access to all objects registered for the server. Objects data could be provided in different formats: binary, XML, GIF/PNG, and JSON. A generic user interface for THttpServer has been implemented with HTML/JavaScript based on JavaScript ROOT development. With any modern web browser one could list, display, and monitor objects available on the server. THttpServer is used in Go4 framework to provide HTTP interface to the online analysis.

  19. Business Models in Emerging Online Services

    NASA Astrophysics Data System (ADS)

    Lyons, Kelly; Playford, Corrie; Messinger, Paul R.; Niu, Run H.; Stroulia, Eleni

    Due to advances in technology and the rapid growth of online services, a significant number of new and inventive web-based service models and delivery methods have been introduced. Although online resources and services are having an impact on more traditional service delivery mechanisms, it is not yet clear how these emerging mechanisms for online service delivery will result in profitable business models. In this paper, we consider emerging business models for online services and their implications for how services are delivered, used, and paid for.We demonstrate the changing roles of user / consumer and provider / seller. We also discuss the applicability of different business models for various domains.

  20. Analytical modeling and feasibility study of a multi-GPU cloud-based server (MGCS) framework for non-voxel-based dose calculations.

    PubMed

    Neylon, J; Min, Y; Kupelian, P; Low, D A; Santhanam, A

    2017-04-01

    In this paper, a multi-GPU cloud-based server (MGCS) framework is presented for dose calculations, exploring the feasibility of remote computing power for parallelization and acceleration of computationally and time intensive radiotherapy tasks in moving toward online adaptive therapies. An analytical model was developed to estimate theoretical MGCS performance acceleration and intelligently determine workload distribution. Numerical studies were performed with a computing setup of 14 GPUs distributed over 4 servers interconnected by a 1 Gigabits per second (Gbps) network. Inter-process communication methods were optimized to facilitate resource distribution and minimize data transfers over the server interconnect. The analytically predicted computation time predicted matched experimentally observations within 1-5 %. MGCS performance approached a theoretical limit of acceleration proportional to the number of GPUs utilized when computational tasks far outweighed memory operations. The MGCS implementation reproduced ground-truth dose computations with negligible differences, by distributing the work among several processes and implemented optimization strategies. The results showed that a cloud-based computation engine was a feasible solution for enabling clinics to make use of fast dose calculations for advanced treatment planning and adaptive radiotherapy. The cloud-based system was able to exceed the performance of a local machine even for optimized calculations, and provided significant acceleration for computationally intensive tasks. Such a framework can provide access to advanced technology and computational methods to many clinics, providing an avenue for standardization across institutions without the requirements of purchasing, maintaining, and continually updating hardware.

  1. Online Internships: A Successful Model

    ERIC Educational Resources Information Center

    DeWitt, Douglas M.; Rogers, Carolyn

    2009-01-01

    Online education has come of age, and along with the advent of online education, there have been numerous calls for improvement in administrator preparation programs. As a result, many administrative preparation programs have revised and reshaped their programs to address this concern. In this regard, this paper will discuss one component of the…

  2. Queueing system analysis of multi server model at XYZ insurance company in Tasikmalaya city

    NASA Astrophysics Data System (ADS)

    Muhajir, Ahmad; Binatari, Nikenasih

    2017-08-01

    Queueing theory or waiting line theory is a theory that deals with the queue process from the customer comes, queue to be served, served and left on service facilities. Queue occurs because of a mismatch between the numbers of customers that will be served with the available number of services, as an example at XYZ insurance company in Tasikmalaya. This research aims to determine the characteristics of the queue system which then to optimize the number of server in term of total cost. The result shows that the queue model can be represented by (M/M/4):(GD/∞/∞), where the arrivals are Poisson distributed while the service time is following exponential distribution. The probability of idle customer service is 2,39% of the working time, the average number of customer in the queue is 3 customers, the average number of customer in a system is 6 customers, the average time of a customer spent in the queue is 15,9979 minutes, the average time a customer spends in the system is 34,4141 minutes, and the average number of busy customer servicer is 3 server. The optimized number of customer service is 5 servers, and the operational cost has minimum cost at Rp 4.323.

  3. DelPhi Web Server: A comprehensive online suite for electrostatic calculations of biological macromolecules and their complexes.

    PubMed

    Sarkar, Subhra; Witham, Shawn; Zhang, Jie; Zhenirovskyy, Maxim; Rocchia, Walter; Alexov, Emil

    2013-01-01

    Here we report a web server, the DelPhi web server, which utilizes DelPhi program to calculate electrostatic energies and the corresponding electrostatic potential and ionic distributions, and dielectric map. The server provides extra services to fix structural defects, as missing atoms in the structural file and allows for generation of missing hydrogen atoms. The hydrogen placement and the corresponding DelPhi calculations can be done with user selected force field parameters being either Charmm22, Amber98 or OPLS. Upon completion of the calculations, the user is given option to download fixed and protonated structural file, together with the parameter and Delphi output files for further analysis. Utilizing Jmol viewer, the user can see the corresponding structural file, to manipulate it and to change the presentation. In addition, if the potential map is requested to be calculated, the potential can be mapped onto the molecule surface. The DelPhi web server is available from http://compbio.clemson.edu/delphi_webserver.

  4. DelPhi Web Server: A comprehensive online suite for electrostatic calculations of biological macromolecules and their complexes

    PubMed Central

    Sarkar, Subhra; Witham, Shawn; Zhang, Jie; Zhenirovskyy, Maxim; Rocchia, Walter; Alexov, Emil

    2011-01-01

    Here we report a web server, the DelPhi web server, which utilizes DelPhi program to calculate electrostatic energies and the corresponding electrostatic potential and ionic distributions, and dielectric map. The server provides extra services to fix structural defects, as missing atoms in the structural file and allows for generation of missing hydrogen atoms. The hydrogen placement and the corresponding DelPhi calculations can be done with user selected force field parameters being either Charmm22, Amber98 or OPLS. Upon completion of the calculations, the user is given option to download fixed and protonated structural file, together with the parameter and Delphi output files for further analysis. Utilizing Jmol viewer, the user can see the corresponding structural file, to manipulate it and to change the presentation. In addition, if the potential map is requested to be calculated, the potential can be mapped onto the molecule surface. The DelPhi web server is available from http://compbio.clemson.edu/delphi_webserver. PMID:24683424

  5. The 1-way on-line coupled atmospheric chemistry model system MECO(n) - Part 2: On-line coupling

    NASA Astrophysics Data System (ADS)

    Kerkweg, A.; Jöckel, P.

    2011-06-01

    A new, highly flexible model system for the seamless dynamical down-scaling of meteorological and chemical processes from the global to the meso-γ scale is presented. A global model and a cascade of an arbitrary number of limited-area model instances run concurrently in the same parallel environment, in which the coarser grained instances provide the boundary data for the finer grained instances. Thus, disk-space intensive and time consuming intermediate and pre-processing steps are entirely avoided and the time interpolation errors of common off-line nesting approaches are minimised. More specifically, the regional model COSMO of the German Weather Service (DWD) is nested on-line into the atmospheric general circulation model ECHAM5 within the Modular Earth Submodel System (MESSy) framework. ECHAM5 and COSMO have previously been equipped with the MESSy infrastructure, implying that the same process formulations (MESSy submodels) are available for both models. This guarantees the highest degree of achievable consistency, between both, the meteorological and chemical conditions at the domain boundaries of the nested limited-area model, and between the process formulations on all scales. The on-line nesting of the different models is established by a client-server approach with the newly developed Multi-Model-Driver (MMD), an additional component of the MESSy infrastructure. With MMD an arbitrary number of model instances can be run concurrently within the same message passing interface (MPI) environment, the respective coarser model (either global or regional) is the server for the nested finer (regional) client model, i.e., it provides the data required to calculate the initial and boundary fields to the client model. On-line nesting means that the coupled (client-server) models exchange their data via the computer memory, in contrast to the data exchange via files on disk in common off-line nesting approaches. MMD consists of a library (Fortran95 and some parts

  6. Scientific Inquiry: A Model for Online Searching.

    ERIC Educational Resources Information Center

    Harter, Stephen P.

    1984-01-01

    Explores scientific inquiry as philosophical and behavioral model for online search specialist and information retrieval process. Nature of scientific research is described and online analogs to research concepts of variable, hypothesis formulation and testing, operational definition, validity, reliability, assumption, and cyclical nature of…

  7. ReFOLD: a server for the refinement of 3D protein models guided by accurate quality estimates.

    PubMed

    Shuid, Ahmad N; Kempster, Robert; McGuffin, Liam J

    2017-04-10

    ReFOLD is a novel hybrid refinement server with integrated high performance global and local Accuracy Self Estimates (ASEs). The server attempts to identify and to fix likely errors in user supplied 3D models of proteins via successive rounds of refinement. The server is unique in providing output for multiple alternative refined models in a way that allows users to quickly visualize the key residue locations, which are likely to have been improved. This is important, as global refinement of a full chain model may not always be possible, whereas local regions, or individual domains, can often be much improved. Thus, users may easily compare the specific regions of the alternative refined models in which they are most interested e.g. key interaction sites or domains. ReFOLD was used to generate hundreds of alternative refined models for the CASP12 experiment, boosting our group's performance in the main tertiary structure prediction category. Our successful refinement of initial server models combined with our built-in ASEs were instrumental to our second place ranking on Template Based Modeling (TBM) and Free Modeling (FM)/TBM targets. The ReFOLD server is freely available at: http://www.reading.ac.uk/bioinf/ReFOLD/. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  8. Shanghai urban green landscape model system based on MapServer

    NASA Astrophysics Data System (ADS)

    Rui, Jianxun; Shi, Beiqi; Shen, Di; Yao, Weiqin

    2008-10-01

    Based on RS and GIS, the 2003a's aerial image data of Shanghai is taken as data source. According to the urban green landscape theory, the green landscapes are well classified to park, street green landscape, affiliation green landscape, inhabited green landscape, production green landscape and defending green landscape, et al. Several spatio-temporal models including the space expansion models and ecological analyzing models for urban green landscape have been constructed and calculated. Then, based on the ORDBMS platform PostgreSQL and OGIS MapServer, the urban green landscape database including the above six types green landscapes spatial data and model system of Shanghai have been developed. At last, using the powerful statistics analysis function of the model system, this paper discusses and reveals the impacts of urban space development on green landscape pattern, structure and function. At the same time, the general distribution characteristics of green landscape pattern have been researched at three levels such as green patch level, type level and mosaics structure of different green landscapes. The urban green landscapes model system of Shanghai based on MapServer provides a powerful interactive and perfect platform for governments to make urban planning decisions and landscape study.

  9. A Comprehensive Availability Modeling and Analysis of a Virtualized Servers System Using Stochastic Reward Nets

    PubMed Central

    Kim, Dong Seong; Park, Jong Sou

    2014-01-01

    It is important to assess availability of virtualized systems in IT business infrastructures. Previous work on availability modeling and analysis of the virtualized systems used a simplified configuration and assumption in which only one virtual machine (VM) runs on a virtual machine monitor (VMM) hosted on a physical server. In this paper, we show a comprehensive availability model using stochastic reward nets (SRN). The model takes into account (i) the detailed failures and recovery behaviors of multiple VMs, (ii) various other failure modes and corresponding recovery behaviors (e.g., hardware faults, failure and recovery due to Mandelbugs and aging-related bugs), and (iii) dependency between different subcomponents (e.g., between physical host failure and VMM, etc.) in a virtualized servers system. We also show numerical analysis on steady state availability, downtime in hours per year, transaction loss, and sensitivity analysis. This model provides a new finding on how to increase system availability by combining both software rejuvenations at VM and VMM in a wise manner. PMID:25165732

  10. An online educational atmospheric global circulation model

    NASA Astrophysics Data System (ADS)

    Navarro, T.; Schott, C.; Forget, F.

    2015-10-01

    As part of online courses on exoplanets of Observatoire de Paris, an online tool designed to vizualise outputs of the Laboratoire de Métérologie Dynamique (LMD) Global Circulation Model (GCM) for various atmospheric circulation regimes has been developed. It includes the possibility for students to visualize 1D and 2D plots along with animations of atmospheric quantities such as temperature, winds, surface pressure, mass flux, etc... from a state-of-the-art model.

  11. Towards second-generation smart card-based authentication in health information systems: the secure server model.

    PubMed

    Hallberg, J; Hallberg, N; Timpka, T

    2001-01-01

    Conventional smart card-based authentication systems used in health care alleviate some of the security issues in user and system authentication. Existing models still do not cover all security aspects. To enable new protective measures to be developed, an extended model of the authentication process is presented. This model includes a new entity referred to as secure server. Assuming a secure server, a method where the smart card is aware of the status of the terminal integrity verification becomes feasible. The card can then act upon this knowledge and restrict the exposure of sensitive information to the terminal as required in order to minimize the risks. The secure server model can be used to illuminate the weaknesses of current approaches and the need for extensions which alleviate the resulting risks.

  12. How Much? Cost Models for Online Education.

    ERIC Educational Resources Information Center

    Lorenzo, George

    2001-01-01

    Reviews some of the research being done in the area of cost models for online education. Describes a cost analysis handbook; an activity-based costing model that was based on an economic model for traditional instruction at the Indiana University Purdue University Indianapolis; and blending other costing models. (LRW)

  13. How Much? Cost Models for Online Education.

    ERIC Educational Resources Information Center

    Lorenzo, George

    2001-01-01

    Reviews some of the research being done in the area of cost models for online education. Describes a cost analysis handbook; an activity-based costing model that was based on an economic model for traditional instruction at the Indiana University Purdue University Indianapolis; and blending other costing models. (LRW)

  14. PRISM: a web server and repository for prediction of protein–protein interactions and modeling their 3D complexes

    PubMed Central

    Baspinar, Alper; Cukuroglu, Engin; Nussinov, Ruth; Keskin, Ozlem; Gursoy, Attila

    2014-01-01

    The PRISM web server enables fast and accurate prediction of protein–protein interactions (PPIs). The prediction algorithm is knowledge-based. It combines structural similarity and accounts for evolutionary conservation in the template interfaces. The predicted models are stored in its repository. Given two protein structures, PRISM will provide a structural model of their complex if a matching template interface is available. Users can download the complex structure, retrieve the interface residues and visualize the complex model. The PRISM web server is user friendly, free and open to all users at http://cosbi.ku.edu.tr/prism. PMID:24829450

  15. The 1-way on-line coupled atmospheric chemistry model system MECO(n) - Part 2: On-line coupling with the Multi-Model-Driver (MMD)

    NASA Astrophysics Data System (ADS)

    Kerkweg, A.; Jöckel, P.

    2012-01-01

    A new, highly flexible model system for the seamless dynamical down-scaling of meteorological and chemical processes from the global to the meso-γ scale is presented. A global model and a cascade of an arbitrary number of limited-area model instances run concurrently in the same parallel environment, in which the coarser grained instances provide the boundary data for the finer grained instances. Thus, disk-space intensive and time consuming intermediate and pre-processing steps are entirely avoided and the time interpolation errors of common off-line nesting approaches are minimised. More specifically, the regional model COSMO of the German Weather Service (DWD) is nested on-line into the atmospheric general circulation model ECHAM5 within the Modular Earth Submodel System (MESSy) framework. ECHAM5 and COSMO have previously been equipped with the MESSy infrastructure, implying that the same process formulations (MESSy submodels) are available for both models. This guarantees the highest degree of achievable consistency, between both, the meteorological and chemical conditions at the domain boundaries of the nested limited-area model, and between the process formulations on all scales. The on-line nesting of the different models is established by a client-server approach with the newly developed Multi-Model-Driver (MMD), an additional component of the MESSy infrastructure. With MMD an arbitrary number of model instances can be run concurrently within the same message passing interface (MPI) environment, the respective coarser model (either global or regional) is the server for the nested finer (regional) client model, i.e. it provides the data required to calculate the initial and boundary fields to the client model. On-line nesting means that the coupled (client-server) models exchange their data via the computer memory, in contrast to the data exchange via files on disk in common off-line nesting approaches. MMD consists of a library (Fortran95 and some parts in

  16. A satellite-driven, client-server hydro-economic model prototype for agricultural water management

    NASA Astrophysics Data System (ADS)

    Maneta, Marco; Kimball, John; He, Mingzhu; Payton Gardner, W.

    2017-04-01

    Anticipating agricultural water demand, land reallocation, and impact on farm revenues associated with different policy or climate constraints is a challenge for water managers and for policy makers. While current integrated decision support systems based on programming methods provide estimates of farmer reaction to external constraints, they have important shortcomings such as the high cost of data collection surveys necessary to calibrate the model, biases associated with inadequate farm sampling, infrequent model updates and recalibration, model overfitting, or their deterministic nature, among other problems. In addition, the administration of water supplies and the generation of policies that promote sustainable agricultural regions depend on more than one bureau or office. Unfortunately, managers from local and regional agencies often use different datasets of variable quality, which complicates coordinated action. To overcome these limitations, we present a client-server, integrated hydro-economic modeling and observation framework driven by satellite remote sensing and other ancillary information from regional monitoring networks. The core of the framework is a stochastic data assimilation system that sequentially ingests remote sensing observations and corrects the parameters of the hydro-economic model at unprecedented spatial and temporal resolutions. An economic model of agricultural production, based on mathematical programming, requires information on crop type and extent, crop yield, crop transpiration and irrigation technology. A regional hydro-climatologic model provides biophysical constraints to an economic model of agricultural production with a level of detail that permits the study of the spatial impact of large- and small-scale water use decisions. Crop type and extent is obtained from the Cropland Data Layer (CDL), which is multi-sensor operational classification of crops maintained by the United States Department of Agriculture. Because

  17. The anisotropic network model web server at 2015 (ANM 2.0).

    PubMed

    Eyal, Eran; Lum, Gengkon; Bahar, Ivet

    2015-05-01

    The anisotropic network model (ANM) is one of the simplest yet powerful tools for exploring protein dynamics. Its main utility is to predict and visualize the collective motions of large complexes and assemblies near their equilibrium structures. The ANM server, introduced by us in 2006 helped making this tool more accessible to non-sophisticated users. We now provide a new version (ANM 2.0), which allows inclusion of nucleic acids and ligands in the network model and thus enables the investigation of the collective motions of protein-DNA/RNA and -ligand systems. The new version offers the flexibility of defining the system nodes and the interaction types and cutoffs. It also includes extensive improvements in hardware, software and graphical interfaces. ANM 2.0 is available at http://anm.csb.pitt.edu eran.eyal@sheba.health.gov.il, eyal.eran@gmail.com. © The Author 2015. Published by Oxford University Press.

  18. Secure IRC Server

    SciTech Connect

    Perry, Marcia

    2003-08-25

    The IRCD is an IRC server that was originally distributed by the IRCD Hybrid developer team for use as a server in IRC message over the public Internet. By supporting the IRC protocol defined in the IRC RFC, IRCD allows the users to create and join channels for group or one-to-one text-based instant messaging. It stores information about channels (e.g., whether it is public, secret, or invite-only, the topic set, membership) and users (who is online and what channels they are members of). It receives messages for a specific user or channel and forwards these messages to the targeted destination. Since server-to-server communication is also supported, these targeted destinations may be connected to different IRC servers. Messages are exchanged over TCP connections that remain open between the client and the server. The IRCD is being used within the Pervasive Computing Collaboration Environment (PCCE) as the 'chat server' for message exchange over public and private channels. After an LBNLSecureMessaging(PCCE chat) client has been authenticated, the client connects to IRCD with its assigned nickname or 'nick.' The client can then create or join channels for group discussions or one-to-one conversations. These channels can have an initial mode of public or invite-only and the mode may be changed after creation. If a channel is public, any one online can join the discussion; if a channel is invite-only, users can only join if existing members of the channel explicity invite them. Users can be invited to any type of channel and users may be members of multiple channels simultaneously. For use with the PCCE environment, the IRCD application (which was written in C) was ported to Linux and has been tested and installed under Linux Redhat 7.2. The source code was also modified with SSL so that all messages exchanged over the network are encrypted. This modified IRC server also verifies with an authentication server that the client is who he or she claims to be and that

  19. Secure IRC Server

    SciTech Connect

    Perry, Marcia

    2003-08-25

    The IRCD is an IRC server that was originally distributed by the IRCD Hybrid developer team for use as a server in IRC message over the public Internet. By supporting the IRC protocol defined in the IRC RFC, IRCD allows the users to create and join channels for group or one-to-one text-based instant messaging. It stores information about channels (e.g., whether it is public, secret, or invite-only, the topic set, membership) and users (who is online and what channels they are members of). It receives messages for a specific user or channel and forwards these messages to the targeted destination. Since server-to-server communication is also supported, these targeted destinations may be connected to different IRC servers. Messages are exchanged over TCP connections that remain open between the client and the server. The IRCD is being used within the Pervasive Computing Collaboration Environment (PCCE) as the 'chat server' for message exchange over public and private channels. After an LBNLSecureMessaging(PCCE chat) client has been authenticated, the client connects to IRCD with its assigned nickname or 'nick.' The client can then create or join channels for group discussions or one-to-one conversations. These channels can have an initial mode of public or invite-only and the mode may be changed after creation. If a channel is public, any one online can join the discussion; if a channel is invite-only, users can only join if existing members of the channel explicity invite them. Users can be invited to any type of channel and users may be members of multiple channels simultaneously. For use with the PCCE environment, the IRCD application (which was written in C) was ported to Linux and has been tested and installed under Linux Redhat 7.2. The source code was also modified with SSL so that all messages exchanged over the network are encrypted. This modified IRC server also verifies with an authentication server that the client is who he or she claims to be and that

  20. HPC Server Performance and Power Consumption for Atmospheric Modeling on GPUs Configured with Different CPU Platforms

    NASA Astrophysics Data System (ADS)

    Posey, Stan; Messmer, Peter; Appleyard, Jeremy

    2015-04-01

    Current trends in high performance computing (HPC) are moving towards the use of graphics processing units (GPUs) to achieve speedups through the extraction of fine-grain parallelism of application software. GPUs have been developed exclusively for computational tasks as massively-parallel co-processors to the CPU, and during 2014 the latest NVIDIA GPU architecture can operate with as many as three CPU platforms. In addition to the conventional use of the x86 CPU architecture with GPUs starting from the mid-2000's, the POWER and ARM-64 architectures have recently become available as x86 alternatives. Today computational efficiency and increased performance per energy-cost are key drivers behind HPC decisions to implement GPU-based servers for atmospheric modeling. The choice of a server CPU platform will influence performance and overall power consumption of a system, and also the available configurations of CPU-to-GPU ratio. It follows that such system design configurations continue to be a critical factor behind scientific decisions to implement models at higher resolutions and possibly with an increased use of ensembles. This presentation will examine the current state of GPU developments for atmospheric modeling with examples from the COSMO dycore and from various WRF physics, and for different CPU platforms. The examples provided will be relevant to science-scale HPC practice of CPU-GPU system configurations based on model resolution requirements of a particular simulation. Performance results will compare use of the latest available CPUs from the three available CPU architectures, both with and without GPU acceleration. Finally a GPU outlook is provided on GPU hardware, software, tools, and programmability for each of the available CPU platforms.

  1. BioDataServer: a SQL-based service for the online integration of life science data.

    PubMed

    Freier, Andreas; Hofestädt, Ralf; Lange, Matthias; Scholz, Uwe; Stephanik, Andreas

    2002-01-01

    Regarding molecular biology, we see an exponential growth of data and knowledge. Among others, this fact is reflected in more than 300 molecular databases which are readily available on the Internet. The usage of these data requires integration tools capable of complex information fusion processes. This paper will present a novel concept for user specific integration of life science data. Our approach is based on a mediator architecture in conjunction with freely adjustable data schemes. The implemented prototype is called BioDataServer and can be accessed on the Internet: http://integration.genophen.de. To realize a comfortable usage of the resulted data sets of the integration process, a SQL-based query language and a XML data format were developed and implemented.

  2. Remote information service access system based on a client-server-service model

    DOEpatents

    Konrad, Allan M.

    1997-01-01

    A local host computing system, a remote host computing system as connected by a network, and service functionalities: a human interface service functionality, a starter service functionality, and a desired utility service functionality, and a Client-Server-Service (CSS) model is imposed on each service functionality. In one embodiment, this results in nine logical components and three physical components (a local host, a remote host, and an intervening network), where two of the logical components are integrated into one Remote Object Client component, and that Remote Object Client component and the other seven logical components are deployed among the local host and remote host in a manner which eases compatibility and upgrade problems, and provides an illusion to a user that a desired utility service supported on a remote host resides locally on the user's local host, thereby providing ease of use and minimal software maintenance for users of that remote service.

  3. Remote information service access system based on a client-server-service model

    DOEpatents

    Konrad, Allan M.

    1996-01-01

    A local host computing system, a remote host computing system as connected by a network, and service functionalities: a human interface service functionality, a starter service functionality, and a desired utility service functionality, and a Client-Server-Service (CSS) model is imposed on each service functionality. In one embodiment, this results in nine logical components and three physical components (a local host, a remote host, and an intervening network), where two of the logical components are integrated into one Remote Object Client component, and that Remote Object Client component and the other seven logical components are deployed among the local host and remote host in a manner which eases compatibility and upgrade problems, and provides an illusion to a user that a desired utility service supported on a remote host resides locally on the user's local host, thereby providing ease of use and minimal software maintenance for users of that remote service.

  4. Remote information service access system based on a client-server-service model

    DOEpatents

    Konrad, A.M.

    1996-08-06

    A local host computing system, a remote host computing system as connected by a network, and service functionalities: a human interface service functionality, a starter service functionality, and a desired utility service functionality, and a Client-Server-Service (CSS) model is imposed on each service functionality. In one embodiment, this results in nine logical components and three physical components (a local host, a remote host, and an intervening network), where two of the logical components are integrated into one Remote Object Client component, and that Remote Object Client component and the other seven logical components are deployed among the local host and remote host in a manner which eases compatibility and upgrade problems, and provides an illusion to a user that a desired utility service supported on a remote host resides locally on the user`s local host, thereby providing ease of use and minimal software maintenance for users of that remote service. 16 figs.

  5. Remote information service access system based on a client-server-service model

    DOEpatents

    Konrad, Allan M.

    1999-01-01

    A local host computing system, a remote host computing system as connected by a network, and service functionalities: a human interface service functionality, a starter service functionality, and a desired utility service functionality, and a Client-Server-Service (CSS) model is imposed on each service functionality. In one embodiment, this results in nine logical components and three physical components (a local host, a remote host, and an intervening network), where two of the logical components are integrated into one Remote Object Client component, and that Remote Object Client component and the other seven logical components are deployed among the local host and remote host in a manner which eases compatibility and upgrade problems, and provides an illusion to a user that a desired utility service supported on a remote host resides locally on the user's local host, thereby providing ease of use and minimal software maintenance for users of that remote service.

  6. Remote information service access system based on a client-server-service model

    DOEpatents

    Konrad, A.M.

    1997-12-09

    A local host computing system, a remote host computing system as connected by a network, and service functionalities: a human interface service functionality, a starter service functionality, and a desired utility service functionality, and a Client-Server-Service (CSS) model is imposed on each service functionality. In one embodiment, this results in nine logical components and three physical components (a local host, a remote host, and an intervening network), where two of the logical components are integrated into one Remote Object Client component, and that Remote Object Client component and the other seven logical components are deployed among the local host and remote host in a manner which eases compatibility and upgrade problems, and provides an illusion to a user that a desired utility service supported on a remote host resides locally on the user`s local host, thereby providing ease of use and minimal software maintenance for users of that remote service. 16 figs.

  7. A Two-Tiered Model for Analyzing Library Web Site Usage Statistics, Part 1: Web Server Logs.

    ERIC Educational Resources Information Center

    Cohen, Laura B.

    2003-01-01

    Proposes a two-tiered model for analyzing web site usage statistics for academic libraries: one tier for library administrators that analyzes measures indicating library use, and a second tier for web site managers that analyzes measures aiding in server maintenance and site design. Discusses the technology of web site usage statistics, and…

  8. An Online Learning Model to Facilitate Learners' Rights to Education

    ERIC Educational Resources Information Center

    Lin, Lin

    2008-01-01

    This paper connects an online learning model to the rights to education that the online educational environments can provide. The model emerges from a study of ninety-two online learners and is composed of three kinds of inquiries, namely, independent inquiry, collaborative inquiry, and formative inquiry towards expert knowledge. Online learners…

  9. Aviation System Analysis Capability Quick Response System Report Server User's Guide

    NASA Technical Reports Server (NTRS)

    Roberts, Eileen R.; Villani, James A.; Wingrove, Earl R., III

    1996-01-01

    This report is a user's guide for the Aviation System Analysis Capability Quick Response System (ASAC QRS) Report Server. The ASAC QRS is an automated online capability to access selected ASAC models and data repositories. It supports analysis by the aviation community. This system was designed by the Logistics Management Institute for the NASA Ames Research Center. The ASAC QRS Report Server allows users to obtain information stored in the ASAC Data Repositories.

  10. Modelling Typical Online Language Learning Activity

    ERIC Educational Resources Information Center

    Montoro, Carlos; Hampel, Regine; Stickler, Ursula

    2014-01-01

    This article presents the methods and results of a four-year-long research project focusing on the language learning activity of individual learners using online tasks conducted at the University of Guanajuato (Mexico) in 2009-2013. An activity-theoretical model (Blin, 2010; Engeström, 1987) of the typical language learning activity was used to…

  11. Scalable Online Network Modeling and Simulation

    DTIC Science & Technology

    2005-08-01

    ONLINE NETWORK MODELING AND SIMULATION 6. AUTHOR(S) Boleslaw Szymanski, Shivkumar Kalyanaraman, Biplab Sikdar and Christopher Carothers 5...PI of this project, Prof. Kenneth Vastola, replaced later by co-PI, Prof. Biplab Sikdar . With significant progress in silicon technologies, storage...Winter Simulation Conference (WSC 󈧈), December 2004. 3. K. Chandrayana, S. Ramakrishnan, B. Sikdar , S. Kalyanaraman, On randomizing the sending

  12. Technology and Online Education: Models for Change

    ERIC Educational Resources Information Center

    Cook, Catherine W.; Sonnenberg, Christian

    2014-01-01

    This paper contends that technology changes advance online education. A number of mobile computing and transformative technologies will be examined and incorporated into a descriptive study. The object of the study will be to design innovative mobile awareness models seeking to understand technology changes for mobile devices and how they can be…

  13. Structural modeling of G-protein coupled receptors: An overview on automatic web-servers.

    PubMed

    Busato, Mirko; Giorgetti, Alejandro

    2016-08-01

    Despite the significant efforts and discoveries during the last few years in G protein-coupled receptor (GPCR) expression and crystallization, the receptors with known structures to date are limited only to a small fraction of human GPCRs. The lack of experimental three-dimensional structures of the receptors represents a strong limitation that hampers a deep understanding of their function. Computational techniques are thus a valid alternative strategy to model three-dimensional structures. Indeed, recent advances in the field, together with extraordinary developments in crystallography, in particular due to its ability to capture GPCRs in different activation states, have led to encouraging results in the generation of accurate models. This, prompted the community of modelers to render their methods publicly available through dedicated databases and web-servers. Here, we present an extensive overview on these services, focusing on their advantages, drawbacks and their role in successful applications. Future challenges in the field of GPCR modeling, such as the predictions of long loop regions and the modeling of receptor activation states are presented as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. A two-tiered on-line server-side bandwidth reservation framework for the real-time delivery of multiple video streams

    NASA Astrophysics Data System (ADS)

    Londoño, Jorge M.; Bestavros, Azer

    2009-01-01

    The advent of virtualization and cloud computing technologies necessitates the development of effective mechanisms for the estimation and reservation of resources needed by content providers to deliver large numbers of video-on-demand (VOD) streams through the cloud. Unfortunately, capacity planning for the QoS-constrained delivery of a large number of VOD streams is inherently difficult as VBR encoding schemes exhibit significant bandwidth variability. In this paper, we present a novel resource management scheme to make such allocation decisions using a mixture of per-stream reservations and an aggregate reservation, shared across all streams to accommodate peak demands. The shared reservation provides capacity slack that enables statistical multiplexing of peak rates, while assuring analytically bounded frame-drop probabilities, which can be adjusted by trading off buffer space (and consequently delay) and bandwidth. Our two-tiered bandwidth allocation scheme enables the delivery of any set of streams with less bandwidth (or equivalently with higher link utilization) than state-of-the-art deterministic smoothing approaches. The algorithm underlying our proposed framework uses three per-stream parameters and is linear in the number of servers, making it particularly well suited for use in an on-line setting. We present results from extensive trace-driven simulations, which confirm the efficiency of our scheme especially for small buffer sizes and delay bounds, and which underscore the significant realizable bandwidth savings, typically yielding losses that are an order of magnitude or more below our analytically derived bounds.

  15. Drug-target interaction prediction: databases, web servers and computational models.

    PubMed

    Chen, Xing; Yan, Chenggang Clarence; Zhang, Xiaotian; Zhang, Xu; Dai, Feng; Yin, Jian; Zhang, Yongdong

    2016-07-01

    Identification of drug-target interactions is an important process in drug discovery. Although high-throughput screening and other biological assays are becoming available, experimental methods for drug-target interaction identification remain to be extremely costly, time-consuming and challenging even nowadays. Therefore, various computational models have been developed to predict potential drug-target associations on a large scale. In this review, databases and web servers involved in drug-target identification and drug discovery are summarized. In addition, we mainly introduced some state-of-the-art computational models for drug-target interactions prediction, including network-based method, machine learning-based method and so on. Specially, for the machine learning-based method, much attention was paid to supervised and semi-supervised models, which have essential difference in the adoption of negative samples. Although significant improvements for drug-target interaction prediction have been obtained by many effective computational models, both network-based and machine learning-based methods have their disadvantages, respectively. Furthermore, we discuss the future directions of the network-based drug discovery and network approach for personalized drug discovery based on personalized medicine, genome sequencing, tumor clone-based network and cancer hallmark-based network. Finally, we discussed the new evaluation validation framework and the formulation of drug-target interactions prediction problem by more realistic regression formulation based on quantitative bioactivity data. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  16. Servers for protein structure prediction.

    PubMed

    Fischer, Daniel

    2006-04-01

    The 1990s cultivated a generation of protein structure human predictors. As a result of structural genomics and genome sequencing projects, and significant improvements in the performance of protein structure prediction methods, a generation of automated servers has evolved in the past few years. Servers for close and distant homology modeling are now routinely used by many biologists, and have already been applied to the experimental structure determination process itself, and to the interpretation and annotation of genome sequences. Because dozens of servers are currently available, it is hard for a biologist to know which server(s) to use; however, the state of the art of these methods is now assessed through the LiveBench and CAFASP experiments. Meta-servers--servers that use the results of other autonomous servers to produce a consensus prediction--have proven to be the best performers, and are already challenging all but a handful of expert human predictors. The difference in performance of the top ten autonomous (non-meta) servers is small and hard to assess using relatively small test sets. Recent experiments suggest that servers will soon free humans from most of the burden of protein structure prediction.

  17. Online Instructors as Thinking Advisors: A Model for Online Learner Adaptation

    ERIC Educational Resources Information Center

    Benedetti, Christopher

    2015-01-01

    This article examines the characteristics and challenges of online instruction and presents a model for improving learner adaptation in an online classroom. Instruction in an online classroom presents many challenges, including learner individualization. Individual differences in learning styles and preferences are often not considered in the…

  18. Incorporating 3-dimensional models in online articles.

    PubMed

    Cevidanes, Lucia H S; Ruellas, Antonio C O; Jomier, Julien; Nguyen, Tung; Pieper, Steve; Budin, Francois; Styner, Martin; Paniagua, Beatriz

    2015-05-01

    The aims of this article are to introduce the capability to view and interact with 3-dimensional (3D) surface models in online publications, and to describe how to prepare surface models for such online 3D visualizations. Three-dimensional image analysis methods include image acquisition, construction of surface models, registration in a common coordinate system, visualization of overlays, and quantification of changes. Cone-beam computed tomography scans were acquired as volumetric images that can be visualized as 3D projected images or used to construct polygonal meshes or surfaces of specific anatomic structures of interest. The anatomic structures of interest in the scans can be labeled with color (3D volumetric label maps), and then the scans are registered in a common coordinate system using a target region as the reference. The registered 3D volumetric label maps can be saved in .obj, .ply, .stl, or .vtk file formats and used for overlays, quantification of differences in each of the 3 planes of space, or color-coded graphic displays of 3D surface distances. All registered 3D surface models in this study were saved in .vtk file format and loaded in the Elsevier 3D viewer. In this study, we describe possible ways to visualize the surface models constructed from cone-beam computed tomography images using 2D and 3D figures. The 3D surface models are available in the article's online version for viewing and downloading using the reader's software of choice. These 3D graphic displays are represented in the print version as 2D snapshots. Overlays and color-coded distance maps can be displayed using the reader's software of choice, allowing graphic assessment of the location and direction of changes or morphologic differences relative to the structure of reference. The interpretation of 3D overlays and quantitative color-coded maps requires basic knowledge of 3D image analysis. When submitting manuscripts, authors can now upload 3D models that will allow readers to

  19. Incorporating 3-dimensional models in online articles

    PubMed Central

    Cevidanes, Lucia H. S.; Ruellasa, Antonio C. O.; Jomier, Julien; Nguyen, Tung; Pieper, Steve; Budin, Francois; Styner, Martin; Paniagua, Beatriz

    2015-01-01

    Introduction The aims of this article were to introduce the capability to view and interact with 3-dimensional (3D) surface models in online publications, and to describe how to prepare surface models for such online 3D visualizations. Methods Three-dimensional image analysis methods include image acquisition, construction of surface models, registration in a common coordinate system, visualization of overlays, and quantification of changes. Cone-beam computed tomography scans were acquired as volumetric images that can be visualized as 3D projected images or used to construct polygonal meshes or surfaces of specific anatomic structures of interest. The anatomic structures of interest in the scans can be labeled with color (3D volumetric label maps), and then the scans are registered in a common coordinate system using a target region as the reference. The registered 3D volumetric label maps can be saved in .obj, .ply, .stl, or .vtk file formats and used for overlays, quantification of differences in each of the 3 planes of space, or color-coded graphic displays of 3D surface distances. Results All registered 3D surface models in this study were saved in .vtk file format and loaded in the Elsevier 3D viewer. In this study, we describe possible ways to visualize the surface models constructed from cone-beam computed tomography images using 2D and 3D figures. The 3D surface models are available in the article’s online version for viewing and downloading using the reader’s software of choice. These 3D graphic displays are represented in the print version as 2D snapshots. Overlays and color-coded distance maps can be displayed using the reader’s software of choice, allowing graphic assessment of the location and direction of changes or morphologic differences relative to the structure of reference. The interpretation of 3D overlays and quantitative color-coded maps requires basic knowledge of 3D image analysis. Conclusions When submitting manuscripts, authors can

  20. An evolving model of online bipartite networks

    NASA Astrophysics Data System (ADS)

    Zhang, Chu-Xu; Zhang, Zi-Ke; Liu, Chuang

    2013-12-01

    Understanding the structure and evolution of online bipartite networks is a significant task since they play a crucial role in various e-commerce services nowadays. Recently, various attempts have been tried to propose different models, resulting in either power-law or exponential degree distributions. However, many empirical results show that the user degree distribution actually follows a shifted power-law distribution, the so-called Mandelbrot’s law, which cannot be fully described by previous models. In this paper, we propose an evolving model, considering two different user behaviors: random and preferential attachment. Extensive empirical results on two real bipartite networks, Delicious and CiteULike, show that the theoretical model can well characterize the structure of real networks for both user and object degree distributions. In addition, we introduce a structural parameter p, to demonstrate that the hybrid user behavior leads to the shifted power-law degree distribution, and the region of power-law tail will increase with the increment of p. The proposed model might shed some lights in understanding the underlying laws governing the structure of real online bipartite networks.

  1. EXpectation Propagation LOgistic REgRession (EXPLORER): Distributed Privacy-Preserving Online Model Learning

    PubMed Central

    Wang, Shuang; Jiang, Xiaoqian; Wu, Yuan; Cui, Lijuan; Cheng, Samuel; Ohno-Machado, Lucila

    2013-01-01

    We developed an EXpectation Propagation LOgistic REgRession (EXPLORER) model for distributed privacy-preserving online learning. The proposed framework provides a high level guarantee for protecting sensitive information, since the information exchanged between the server and the client is the encrypted posterior distribution of coefficients. Through experimental results, EXPLORER shows the same performance (e.g., discrimination, calibration, feature selection etc.) as the traditional frequentist Logistic Regression model, but provides more flexibility in model updating. That is, EXPLORER can be updated one point at a time rather than having to retrain the entire data set when new observations are recorded. The proposed EXPLORER supports asynchronized communication, which relieves the participants from coordinating with one another, and prevents service breakdown from the absence of participants or interrupted communications. PMID:23562651

  2. Parallel Computing Using Web Servers and "Servlets".

    ERIC Educational Resources Information Center

    Lo, Alfred; Bloor, Chris; Choi, Y. K.

    2000-01-01

    Describes parallel computing and presents inexpensive ways to implement a virtual parallel computer with multiple Web servers. Highlights include performance measurement of parallel systems; models for using Java and intranet technology including single server, multiple clients and multiple servers, single client; and a comparison of CGI (common…

  3. Dynamic online sewer modelling in Helsingborg.

    PubMed

    Hernebring, C; Jönsson, L E; Thorén, U B; Møller, A

    2002-01-01

    Within the last decade, the sewer system in Helsingborg, Sweden has been rehabilitated in many ways along with the reconstruction of the WWTP Oresundsverket in order to obtain a high degree of nitrogen and phosphorus removal. In that context a holistic view has been applied in order to optimise the corrective measures as seen from the effects in the receiving waters. A sewer catchment model has been used to evaluate several operation strategies and the effect of introducing RTC. Recently, a MOUSE ONLINE system was installed. In this phase the objective is to establish a stable communication with the SCADA system and to generate short-term flow forecasts.

  4. Levels of Interaction Provided by Online Distance Education Models

    ERIC Educational Resources Information Center

    Alhih, Mohammed; Ossiannilsson, Ebba; Berigel, Muhammet

    2017-01-01

    Interaction plays a significant role to foster usability and quality in online education. It is one of the quality standard to reveal the evidence of practice in online distance education models. This research study aims to evaluate levels of interaction in the practices of distance education centres. It is aimed to provide online distance…

  5. CORAL Server and CORAL Server Proxy: Scalable Access to Relational Databases from CORAL Applications

    SciTech Connect

    Valassi, A.; Bartoldus, R.; Kalkhof, A.; Salnikov, A.; Wache, M.; /Mainz U., Inst. Phys.

    2012-04-19

    The CORAL software is widely used at CERN by the LHC experiments to access the data they store on relational databases, such as Oracle. Two new components have recently been added to implement a model involving a middle tier 'CORAL server' deployed close to the database and a tree of 'CORAL server proxies', providing data caching and multiplexing, deployed close to the client. A first implementation of the two new components, released in the summer 2009, is now deployed in the ATLAS online system to read the data needed by the High Level Trigger, allowing the configuration of a farm of several thousand processes. This paper reviews the architecture of the software, its development status and its usage in ATLAS.

  6. Model-based online learning with kernels.

    PubMed

    Li, Guoqi; Wen, Changyun; Li, Zheng Guo; Zhang, Aimin; Yang, Feng; Mao, Kezhi

    2013-03-01

    New optimization models and algorithms for online learning with Kernels (OLK) in classification, regression, and novelty detection are proposed in a reproducing Kernel Hilbert space. Unlike the stochastic gradient descent algorithm, called the naive online Reg minimization algorithm (NORMA), OLK algorithms are obtained by solving a constrained optimization problem based on the proposed models. By exploiting the techniques of the Lagrange dual problem like Vapnik's support vector machine (SVM), the solution of the optimization problem can be obtained iteratively and the iteration process is similar to that of the NORMA. This further strengthens the foundation of OLK and enriches the research area of SVM. We also apply the obtained OLK algorithms to problems in classification, regression, and novelty detection, including real time background substraction, to show their effectiveness. It is illustrated that, based on the experimental results of both classification and regression, the accuracy of OLK algorithms is comparable with traditional SVM-based algorithms, such as SVM and least square SVM (LS-SVM), and with the state-of-the-art algorithms, such as Kernel recursive least square (KRLS) method and projectron method, while it is slightly higher than that of NORMA. On the other hand, the computational cost of the OLK algorithm is comparable with or slightly lower than existing online methods, such as above mentioned NORMA, KRLS, and projectron methods, but much lower than that of SVM-based algorithms. In addition, different from SVM and LS-SVM, it is possible for OLK algorithms to be applied to non-stationary problems. Also, the applicability of OLK in novelty detection is illustrated by simulation results.

  7. Oceanotron server for marine in-situ observations : a thematic data model implementation as a basis for the extensibility

    NASA Astrophysics Data System (ADS)

    Loubrieu, T.; Donnart, J. C.; Bregent, S.; Blower, J.; Griffith, G.

    2012-04-01

    Oceanotron (https://forge.ifremer.fr/plugins/mediawiki/wiki/oceanotron/index.php/Accueil) is an open-source data server dedicated to marine in-situ observation dissemination. For its extensibility it relies of an ocean business data model. IFREMER hosts the CORIOLIS marine in-situ data centre (http://www.coriolis.eu.org) and, as French NODC (National Oceanographic Data Centre, http://www.ifremer.fr/sismer/index_UK.htm), some other in-situ observation databases. As such IFREMER participates to numerous ocean data management projects. IFREMER wished to capitalize its thematic data management expertise in a dedicated data dissemination server called Oceanotron. The development of the server coordinated by IFREMER has started in 2010. Knowing the diversity of data repository formats (RDBMS, netCDF, ODV, MEDATLAS, ...) and the temperamental nature of the standard interoperability interface profiles (OGC/WMS, OGC/WFS, OGC/SOS, OpenDAP, …), the architecture of the software relies on an ocean business data model dedicated to marine in-situ observation features. The ocean business data model relies on the CSML conceptual modelling (http://csml.badc.rl.ac.uk/) and UNIDATA Common Data Model (http://www.unidata.ucar.edu/software/netcdf-java/CDM/) works and focuses on the most common marine observation features which are : vertical profiles, point series, trajectories and point. The ocean business data model has been implemented in java and can be used as an API. The oceanotron server orchestrates different types of modules handling the ocean business data model objects : - StorageUnits : which read specific data repository formats (netCDF/OceanSites, netCDF/ARGO, ...). - TransformationUnits : which apply useful ocean business related transformation to the features (for example conversion of vertical coordinates from pressure in dB to meters under sea surface). - FrontDesks : which get external requests and send results for interoperable protocols (OpenDAP, WMS, ...). These

  8. Consumer's Online Shopping Influence Factors and Decision-Making Model

    NASA Astrophysics Data System (ADS)

    Yan, Xiangbin; Dai, Shiliang

    Previous research on online consumer behavior has mostly been confined to the perceived risk which is used to explain those barriers for purchasing online. However, perceived benefit is another important factor which influences consumers’ decision when shopping online. As a result, an integrated consumer online shopping decision-making model is developed which contains three elements—Consumer, Product, and Web Site. This model proposed relative factors which influence the consumers’ intention during the online shopping progress, and divided them into two different dimensions—mentally level and material level. We tested those factors with surveys, from both online volunteers and offline paper surveys with more than 200 samples. With the help of SEM, the experimental results show that the proposed model and method can be used to analyze consumer’s online shopping decision-making process effectively.

  9. The IntFOLD server: an integrated web resource for protein fold recognition, 3D model quality assessment, intrinsic disorder prediction, domain prediction and ligand binding site prediction.

    PubMed

    Roche, Daniel B; Buenavista, Maria T; Tetchner, Stuart J; McGuffin, Liam J

    2011-07-01

    The IntFOLD server is a novel independent server that integrates several cutting edge methods for the prediction of structure and function from sequence. Our guiding principles behind the server development were as follows: (i) to provide a simple unified resource that makes our prediction software accessible to all and (ii) to produce integrated output for predictions that can be easily interpreted. The output for predictions is presented as a simple table that summarizes all results graphically via plots and annotated 3D models. The raw machine readable data files for each set of predictions are also provided for developers, which comply with the Critical Assessment of Methods for Protein Structure Prediction (CASP) data standards. The server comprises an integrated suite of five novel methods: nFOLD4, for tertiary structure prediction; ModFOLD 3.0, for model quality assessment; DISOclust 2.0, for disorder prediction; DomFOLD 2.0 for domain prediction; and FunFOLD 1.0, for ligand binding site prediction. Predictions from the IntFOLD server were found to be competitive in several categories in the recent CASP9 experiment. The IntFOLD server is available at the following web site: http://www.reading.ac.uk/bioinf/IntFOLD/.

  10. Development of an integrated modelling framework: comparing client-server and demand-driven control flow for model execution

    NASA Astrophysics Data System (ADS)

    Schmitz, Oliver; Karssenberg, Derek; de Jong, Kor; de Kok, Jean-Luc; de Jong, Steven M.

    2014-05-01

    The construction of hydrological models at the catchment or global scale depends on the integration of component models representing various environmental processes, often operating at different spatial and temporal discretisations. A flexible construction of spatio-temporal model components, a means to specify aggregation or disaggregation to bridge discretisation discrepancies, ease of coupling these into complex integrated models, and support for stochastic modelling and the assessment of model outputs are the desired functionalities for the development of integrated models. These functionalities are preferably combined into one modelling framework such that domain specialists can perform exploratory model development without the need to change their working environment. We implemented an integrated modelling framework in the Python programming language, providing support for 1) model construction and 2) model execution. The framework enables modellers to represent spatio-temporal processes or to specify spatio-temporal (dis)aggregation with map algebra operations provided by the PCRaster library. Model algebra operations can be used by the modeller to specify the exchange of data and therefore the coupling of components. The framework determines the control flow for the ordered execution based on the time steps and couplings of the model components given by the modeller. We implemented two different control flow mechanisms. First, a client-server approach is used with a central entity controlling the execution of the component models and steering the data exchange. Second, a demand-driven approach is used that triggers the execution of a component model when data is requested by a coupled component model. We show that both control flow mechanisms allow for the execution of stochastic, multi-scale integrated models. We examine the implications of each control flow mechanism on the terminology used by the modeller to specify integrated models, and illustrate the

  11. EarthServer - an FP7 project to enable the web delivery and analysis of 3D/4D models

    NASA Astrophysics Data System (ADS)

    Laxton, John; Sen, Marcus; Passmore, James

    2013-04-01

    EarthServer aims at open access and ad-hoc analytics on big Earth Science data, based on the OGC geoservice standards Web Coverage Service (WCS) and Web Coverage Processing Service (WCPS). The WCS model defines "coverages" as a unifying paradigm for multi-dimensional raster data, point clouds, meshes, etc., thereby addressing a wide range of Earth Science data including 3D/4D models. WCPS allows declarative SQL-style queries on coverages. The project is developing a pilot implementing these standards, and will also investigate the use of GeoSciML to describe coverages. Integration of WCPS with XQuery will in turn allow coverages to be queried in combination with their metadata and GeoSciML description. The unified service will support navigation, extraction, aggregation, and ad-hoc analysis on coverage data from SQL. Clients will range from mobile devices to high-end immersive virtual reality, and will enable 3D model visualisation using web browser technology coupled with developing web standards. EarthServer is establishing open-source client and server technology intended to be scalable to Petabyte/Exabyte volumes, based on distributed processing, supercomputing, and cloud virtualization. Implementation will be based on the existing rasdaman server technology developed. Services using rasdaman technology are being installed serving the atmospheric, oceanographic, geological, cryospheric, planetary and general earth observation communities. The geology service (http://earthserver.bgs.ac.uk/) is being provided by BGS and at present includes satellite imagery, superficial thickness data, onshore DTMs and 3D models for the Glasgow area. It is intended to extend the data sets available to include 3D voxel models. Use of the WCPS standard allows queries to be constructed against single or multiple coverages. For example on a single coverage data for a particular area can be selected or data with a particular range of pixel values. Queries on multiple surfaces can be

  12. Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System.

    PubMed

    Lee, Chengming; Chen, Rongshun

    2015-05-20

    Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server's fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption.

  13. E-Model for Online Learning Communities.

    PubMed

    Rogo, Ellen J; Portillo, Karen M

    2015-10-01

    The purpose of this study was to explore the students' perspectives on the phenomenon of online learning communities while enrolled in a graduate dental hygiene program. A qualitative case study method was designed to investigate the learners' experiences with communities in an online environment. A cross-sectional purposive sampling method was used. Interviews were the data collection method. As the original data were being analyzed, the researchers noted a pattern evolved indicating the phenomenon developed in stages. The data were re-analyzed and validated by 2 member checks. The participants' experiences revealed an e-model consisting of 3 stages of formal learning community development as core courses in the curriculum were completed and 1 stage related to transmuting the community to an informal entity as students experienced the independent coursework in the program. The development of the formal learning communities followed 3 stages: Building a Foundation for the Learning Community, Building a Supportive Network within the Learning Community and Investing in the Community to Enhance Learning. The last stage, Transforming the Learning Community, signaled a transition to an informal network of learners. The e-model was represented by 3 key elements: metamorphosis of relationships, metamorphosis through the affective domain and metamorphosis through the cognitive domain, with the most influential element being the affective development. The e-model describes a 4 stage process through which learners experience a metamorphosis in their affective, relationship and cognitive development. Synergistic learning was possible based on the interaction between synergistic relationships and affective actions. Copyright © 2015 The American Dental Hygienists’ Association.

  14. University Business Models and Online Practices: A Third Way

    ERIC Educational Resources Information Center

    Rubin, Beth

    2013-01-01

    Higher Education is in a state of change, and the existing business models do not meet the needs of stakeholders. This article contrasts the current dominant business models of universities, comparing the traditional non-profit against the for-profit online model, examining the structural features and online teaching practices that underlie each.…

  15. University Business Models and Online Practices: A Third Way

    ERIC Educational Resources Information Center

    Rubin, Beth

    2013-01-01

    Higher Education is in a state of change, and the existing business models do not meet the needs of stakeholders. This article contrasts the current dominant business models of universities, comparing the traditional non-profit against the for-profit online model, examining the structural features and online teaching practices that underlie each.…

  16. Load balancing techniques for scalable web servers

    NASA Astrophysics Data System (ADS)

    Bryhni, Haakon; Klovning, Espen; Kure, Oivind

    1998-10-01

    Scalable web servers can be built using a Network of Workstations (NOW) where server capability can be added by adding new workstations as the workload increases. The task of load balancing Hyper Text Transfer Protocol traffic to scalable web servers is the topic of this paper. We present a classification framework for scalable web servers, and present simulations of a clustered web server. The cluster communication is modeled using a detailed, verified model of TCP/IP processing over Asynchronous Transfer Mode. The simulator is a trace driven discrete even simulator, and the traces are obtained from the proxy server of a large Internet Service Provider in Norway. Various load balancing schemes are simulated for Robin load balancing policy implemented in a modified router gives better average response time and better load balancing than the Rotating Nameserver method used in current scalable web servers.

  17. Modeling and planning distributed energy systems online

    NASA Astrophysics Data System (ADS)

    Wieler, Susana

    Sustainable energy is a core concern worldwide for the foreseeable future. Technologically, its key trends are distributed and renewable energy resources and smart grid capabilities. At the same time, a global need for sustainable energy is meeting increasingly diverse energy policy and economics. To plan with such complex contexts and systems, a novel distributed energy software tool and its initial implementation is presented: the Energy Systems Evaluator Online (ESEO). Its contributions include: (1) A flexible model framework that can simulate current and expected distributed energy systems; (2) An architecture specifying the modular design needed for distributed energy planning software in general; (3) A working implementation as the first general energy planning tool deployed via the Internet with collaborative capabilities.

  18. SimRNAweb: a web server for RNA 3D structure modeling with optional restraints.

    PubMed

    Magnus, Marcin; Boniecki, Michał J; Dawson, Wayne; Bujnicki, Janusz M

    2016-07-08

    RNA function in many biological processes depends on the formation of three-dimensional (3D) structures. However, RNA structure is difficult to determine experimentally, which has prompted the development of predictive computational methods. Here, we introduce a user-friendly online interface for modeling RNA 3D structures using SimRNA, a method that uses a coarse-grained representation of RNA molecules, utilizes the Monte Carlo method to sample the conformational space, and relies on a statistical potential to describe the interactions in the folding process. SimRNAweb makes SimRNA accessible to users who do not normally use high performance computational facilities or are unfamiliar with using the command line tools. The simplest input consists of an RNA sequence to fold RNA de novo. Alternatively, a user can provide a 3D structure in the PDB format, for instance a preliminary model built with some other technique, to jump-start the modeling close to the expected final outcome. The user can optionally provide secondary structure and distance restraints, and can freeze a part of the starting 3D structure. SimRNAweb can be used to model single RNA sequences and RNA-RNA complexes (up to 52 chains). The webserver is available at http://genesilico.pl/SimRNAweb. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. SimRNAweb: a web server for RNA 3D structure modeling with optional restraints

    PubMed Central

    Magnus, Marcin; Boniecki, Michał J.; Dawson, Wayne; Bujnicki, Janusz M.

    2016-01-01

    RNA function in many biological processes depends on the formation of three-dimensional (3D) structures. However, RNA structure is difficult to determine experimentally, which has prompted the development of predictive computational methods. Here, we introduce a user-friendly online interface for modeling RNA 3D structures using SimRNA, a method that uses a coarse-grained representation of RNA molecules, utilizes the Monte Carlo method to sample the conformational space, and relies on a statistical potential to describe the interactions in the folding process. SimRNAweb makes SimRNA accessible to users who do not normally use high performance computational facilities or are unfamiliar with using the command line tools. The simplest input consists of an RNA sequence to fold RNA de novo. Alternatively, a user can provide a 3D structure in the PDB format, for instance a preliminary model built with some other technique, to jump-start the modeling close to the expected final outcome. The user can optionally provide secondary structure and distance restraints, and can freeze a part of the starting 3D structure. SimRNAweb can be used to model single RNA sequences and RNA-RNA complexes (up to 52 chains). The webserver is available at http://genesilico.pl/SimRNAweb. PMID:27095203

  20. Stochastic Online Learning in Dynamic Networks under Unknown Models

    DTIC Science & Technology

    2016-08-02

    Stochastic Online Learning in Dynamic Networks under Unknown Models This research aims to develop fundamental theories and practical algorithms for...12211 Research Triangle Park, NC 27709-2211 Online learning, multi-armed bandit, dynamic networks REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S... Online Learning in Dynamic Networks under Unknown Models Report Title This research aims to develop fundamental theories and practical algorithms for

  1. ProServer: a simple, extensible Perl DAS server.

    PubMed

    Finn, Robert D; Stalker, James W; Jackson, David K; Kulesha, Eugene; Clements, Jody; Pettett, Roger

    2007-06-15

    The increasing size and complexity of biological databases has led to a growing trend to federate rather than duplicate them. In order to share data between federated databases, protocols for the exchange mechanism must be developed. One such data exchange protocol that is widely used is the Distributed Annotation System (DAS). For example, DAS has enabled small experimental groups to integrate their data into the Ensembl genome browser. We have developed ProServer, a simple, lightweight, Perl-based DAS server that does not depend on a separate HTTP server. The ProServer package is easily extensible, allowing data to be served from almost any underlying data model. Recent additions to the DAS protocol have enabled both structure and alignment (sequence and structural) data to be exchanged. ProServer allows both of these data types to be served. ProServer can be downloaded from http://www.sanger.ac.uk/proserver/ or CPAN http://search.cpan.org/~rpettett/. Details on the system requirements and installation of ProServer can be found at http://www.sanger.ac.uk/proserver/.

  2. Modeling of protein-peptide interactions using the CABS-dock web server for binding site search and flexible docking.

    PubMed

    Blaszczyk, Maciej; Kurcinski, Mateusz; Kouza, Maksim; Wieteska, Lukasz; Debinski, Aleksander; Kolinski, Andrzej; Kmiecik, Sebastian

    2016-01-15

    Protein-peptide interactions play essential functional roles in living organisms and their structural characterization is a hot subject of current experimental and theoretical research. Computational modeling of the structure of protein-peptide interactions is usually divided into two stages: prediction of the binding site at a protein receptor surface, and then docking (and modeling) the peptide structure into the known binding site. This paper presents a comprehensive CABS-dock method for the simultaneous search of binding sites and flexible protein-peptide docking, available as a user's friendly web server. We present example CABS-dock results obtained in the default CABS-dock mode and using its advanced options that enable the user to increase the range of flexibility for chosen receptor fragments or to exclude user-selected binding modes from docking search. Furthermore, we demonstrate a strategy to improve CABS-dock performance by assessing the quality of models with classical molecular dynamics. Finally, we discuss the promising extensions and applications of the CABS-dock method and provide a tutorial appendix for the convenient analysis and visualization of CABS-dock results. The CABS-dock web server is freely available at http://biocomp.chem.uw.edu.pl/CABSdock/.

  3. LASP Time Series Server (LaTiS): Overcoming Data Access Barriers via a Common Data Model in the Middle Tier (Invited)

    NASA Astrophysics Data System (ADS)

    Lindholm, D. M.; Wilson, A.

    2010-12-01

    The Laboratory for Atmospheric and Space Physics at the University of Colorado has developed an Open Source, OPeNDAP compliant, Java Servlet based, RESTful web service to serve time series data. In addition to handling OPeNDAP style requests and returning standard responses, existing modules for alternate output formats can be reused or customized. It is also simple to reuse or customize modules to directly read various native data sources and even to perform some processing on the server. The server is built around a common data model based on the Unidata Common Data Model (CDM) which merges the NetCDF, HDF, and OPeNDAP data models. The server framework features a modular architecture that supports pluggable Readers, Writers, and Filters via the common interface to the data, enabling a workflow that reads data from their native form, performs some processing on the server, and presents the results to the client in its preferred form. The service is currently being used operationally to serve time series data for the LASP Interactive Solar Irradiance Data Center (LISIRD, http://lasp.colorado.edu/lisird/) and as part of the Time Series Data Server (TSDS, http://tsds.net/). I will present the data model and how it enables reading, writing, and processing concerns to be separated into loosely coupled components. I will also share thoughts for evolving beyond the time series abstraction and providing a general purpose data service that can be orchestrated into larger workflows.

  4. A Conceptual Model for Engagement of the Online Learner

    ERIC Educational Resources Information Center

    Angelino, Lorraine M.; Natvig, Deborah

    2009-01-01

    Engagement of the online learner is one approach to reduce attrition rates. Attrition rates for classes taught through distance education are 10-20% higher than classes taught in a face-to-face setting. This paper introduces a Model for Engagement and provides strategies to engage the online learner. The Model depicts various opportunities where…

  5. A communication server for telemedicine applications.

    PubMed

    Bai, J; Hu, B; Zhang, Y; Ye, D

    1997-09-01

    The telemedicine applications, in some cases, need multipoint-to-multipoint communication. To meet the requirement of telemedicine communication, the development of a medical communication server is proposed in this paper. To make a working, as well as cost-effective, communication platform for the telemedicine applications, a specially designed communication server model is proposed in this work. This server is able to provide an effective multipoint-to-multipoint communication service for any level applications in telemedicine. The implementation program of this server is developed in a Windows'95 environment by using a winsocket. The trial application testing in a telemonitoring system is also presented to demonstrate the feasibility of taking such a structure with the server. By using the architecture of such a communication server in telemedicine applications, the multipoint-to-multipoint communication is easily managed and the communication processes are simplified and well controlled by the server.

  6. Planning for Online Education: A Systems Model

    ERIC Educational Resources Information Center

    Picciano, Anthony G.

    2015-01-01

    The purpose of this article is to revisit the basic principles of technology planning as applied to online education initiatives. While not meant to be an exhaustive treatment of the topic, the article is timely because many colleges and universities are considering the development and expansion of online education as part of their planning…

  7. On-Line Distance Learning: A Model for Developing Countries.

    ERIC Educational Resources Information Center

    Khan, Abdul W.

    2000-01-01

    Discusses issues related to open and distance-learning (ODL) in developing countries, using the virtual campus initiative of the Indira Gandhi National Open University (India) as an example and model of on-line program delivery and on-line, for-profit telelearning centers. Suggests strategies to enable open and distance-learning institutions to…

  8. Student Migration to Online Education: An Economic Model

    ERIC Educational Resources Information Center

    Eisenhauer, Joseph G.

    2013-01-01

    The popularity of distance education has increasingly led universities to consider expanding their online offerings. Remarkably few financial models have been presented for online courses, however, and fewer still have investigated the economic consequences of the migration, or cross-over, of students from traditional classes within the…

  9. Research on Model of Student Engagement in Online Learning

    ERIC Educational Resources Information Center

    Peng, Wang

    2017-01-01

    In this study, online learning refers students under the guidance of teachers through the online learning platform for organized learning. Based on the analysis of related research results, considering the existing problems, the main contents of this paper include the following aspects: (1) Analyze and study the current student engagement model.…

  10. On-Line Distance Learning: A Model for Developing Countries.

    ERIC Educational Resources Information Center

    Khan, Abdul W.

    2000-01-01

    Discusses issues related to open and distance-learning (ODL) in developing countries, using the virtual campus initiative of the Indira Gandhi National Open University (India) as an example and model of on-line program delivery and on-line, for-profit telelearning centers. Suggests strategies to enable open and distance-learning institutions to…

  11. The ABC's of Online Course Design According to Addie Model

    ERIC Educational Resources Information Center

    Durak, Gürhan; Ataizi, Murat

    2016-01-01

    The purpose of this study was to design the course of Programming Languages-I online, which is given on face-to-face basis at undergraduate level. It is seen in literature that there is no detailed research on the preparation of a fully-online course directly based on an instructional design model. In this respect, depending on the ADDIE design…

  12. Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System

    PubMed Central

    Lee, Chengming; Chen, Rongshun

    2015-01-01

    Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server’s fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption. PMID:26007725

  13. jpHMM at GOBICS: a web server to detect genomic recombinations in HIV-1.

    PubMed

    Zhang, Ming; Schultz, Anne-Kathrin; Calef, Charles; Kuiken, Carla; Leitner, Thomas; Korber, Bette; Morgenstern, Burkhard; Stanke, Mario

    2006-07-01

    Detecting recombinations in the genome sequence of human immunodeficiency virus (HIV-1) is crucial for epidemiological studies and for vaccine development. Herein, we present a web server for subtyping and localization of phylogenetic breakpoints in HIV-1. Our software is based on a jumping profile Hidden Markov Model (jpHMM), a probabilistic generalization of the jumping-alignment approach proposed by Spang et al. The input data for our server is a partial or complete genome sequence from HIV-1; our tool assigns regions of the input sequence to known subtypes of HIV-1 and predicts phylogenetic breakpoints. jpHMM is available online at http://jphmm.gobics.de/.

  14. Earth System Model Development and Analysis using FRE-Curator and Live Access Servers: On-demand analysis of climate model output with data provenance.

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, A.; Balaji, V.; Schweitzer, R.; Nikonov, S.; O'Brien, K.; Vahlenkamp, H.; Burger, E. F.

    2016-12-01

    There are distinct phases in the development cycle of an Earth system model. During the model development phase, scientists make changes to code and parameters and require rapid access to results for evaluation. During the production phase, scientists may make an ensemble of runs with different settings, and produce large quantities of output, that must be further analyzed and quality controlled for scientific papers and submission to international projects such as the Climate Model Intercomparison Project (CMIP). During this phase, provenance is a key concern:being able to track back from outputs to inputs. We will discuss one of the paths taken at GFDL in delivering tools across this lifecycle, offering on-demand analysis of data by integrating the use of GFDL's in-house FRE-Curator, Unidata's THREDDS and NOAA PMEL's Live Access Servers (LAS).Experience over this lifecycle suggests that a major difficulty in developing analysis capabilities is only partially the scientific content, but often devoted to answering the questions "where is the data?" and "how do I get to it?". "FRE-Curator" is the name of a database-centric paradigm used at NOAA GFDL to ingest information about the model runs into an RDBMS (Curator database). The components of FRE-Curator are integrated into Flexible Runtime Environment workflow and can be invoked during climate model simulation. The front end to FRE-Curator, known as the Model Development Database Interface (MDBI) provides an in-house web-based access to GFDL experiments: metadata, analysis output and more. In order to provide on-demand visualization, MDBI uses Live Access Servers which is a highly configurable web server designed to provide flexible access to geo-referenced scientific data, that makes use of OPeNDAP. Model output saved in GFDL's tape archive, the size of the database and experiments, continuous model development initiatives with more dynamic configurations add complexity and challenges in providing an on

  15. RMS ENVELOPE BACK-PROPAGATION IN THE XAL ONLINE MODEL

    SciTech Connect

    Allen, Christopher K; Sako, Hiroyuki; Ikegami, Masanori

    2009-01-01

    The ability to back-propagate RMS envelopes was added to the J-PARC XAL online model. Specifically, given an arbitrary downstream location, the online model can propagate the RMS envelopes backward to an arbitrary upstream location. This feature provides support for algorithms estimating upstream conditions from downstream data. The upgrade required significant refactoring, which we outline. We also show simulations using the new feature.

  16. Online Educational Delivery Models: A Descriptive View

    ERIC Educational Resources Information Center

    Hill, Phil

    2012-01-01

    Although there has been a long history of distance education, the creation of online education occurred just over a decade and a half ago--a relatively short time in academic terms. Early course delivery via the web had started by 1994, soon followed by a more structured approach using the new category of course management systems. Since that…

  17. Online Educational Delivery Models: A Descriptive View

    ERIC Educational Resources Information Center

    Hill, Phil

    2012-01-01

    Although there has been a long history of distance education, the creation of online education occurred just over a decade and a half ago--a relatively short time in academic terms. Early course delivery via the web had started by 1994, soon followed by a more structured approach using the new category of course management systems. Since that…

  18. The Targeted Open Online Course (TOOC) Model

    ERIC Educational Resources Information Center

    Baker, Credence; Gentry, James

    2014-01-01

    In an era of increasingly hyped Massive Open Online Courses (MOOCs) that seem to evoke feelings of both promise and peril for higher education, many institutions are struggling to find their niche among top-tier Ivy League schools offering courses to thousands of participants for free. While the effectiveness of MOOCs in terms of learning outcomes…

  19. ProTSAV: A protein tertiary structure analysis and validation server.

    PubMed

    Singh, Ankita; Kaushik, Rahul; Mishra, Avinash; Shanker, Asheesh; Jayaram, B

    2016-01-01

    Quality assessment of predicted model structures of proteins is as important as the protein tertiary structure prediction. A highly efficient quality assessment of predicted model structures directs further research on function. Here we present a new server ProTSAV, capable of evaluating predicted model structures based on some popular online servers and standalone tools. ProTSAV furnishes the user with a single quality score in case of individual protein structure along with a graphical representation and ranking in case of multiple protein structure assessment. The server is validated on ~64,446 protein structures including experimental structures from RCSB and predicted model structures for CASP targets and from public decoy sets. ProTSAV succeeds in predicting quality of protein structures with a specificity of 100% and a sensitivity of 98% on experimentally solved structures and achieves a specificity of 88%and a sensitivity of 91% on predicted protein structures of CASP11 targets under 2Å.The server overcomes the limitations of any single server/method and is seen to be robust in helping in quality assessment. ProTSAV is freely available at http://www.scfbio-iitd.res.in/software/proteomics/protsav.jsp. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Generic OPC UA Server Framework

    NASA Astrophysics Data System (ADS)

    Nikiel, Piotr P.; Farnham, Benjamin; Filimonov, Viatcheslav; Schlenker, Stefan

    2015-12-01

    This paper describes a new approach for generic design and efficient development of OPC UA servers. Development starts with creation of a design file, in XML format, describing an object-oriented information model of the target system or device. Using this model, the framework generates an executable OPC UA server application, which exposes the per-design OPC UA address space, without the developer writing a single line of code. Furthermore, the framework generates skeleton code into which the developer adds the necessary logic for integration to the target system or device. This approach allows both developers unfamiliar with the OPC UA standard, and advanced OPC UA developers, to create servers for the systems they are experts in while greatly reducing design and development effort as compared to developments based purely on COTS OPC UA toolkits. Higher level software may further benefit from the explicit OPC UA server model by using the XML design description as the basis for generating client connectivity configuration and server data representation. Moreover, having the XML design description at hand facilitates automatic generation of validation tools. In this contribution, the concept and implementation of this framework is detailed along with examples of actual production-level usage in the detector control system of the ATLAS experiment at CERN and beyond.

  1. Configuring Battalion File Servers

    DTIC Science & Technology

    2012-01-01

    AGM Server 2008 to load on a Dell D630 laptop. Though not ideal, it did allow the battalion staff and command group to share...and install the AGM Microsoft Server 2008. The final contract included two Dell R610 1U servers with RAID 5 comprising of three 1 TB hard drives...continuity in data between garrison and deployment environ- ments. With the usage of AGM Server operating systems, the Army is

  2. USING SERVERS TO ENHANCE CONTROL SYSTEM CAPABILITY.

    SciTech Connect

    BICKLEY,M.; BOWLING,B.A.; BRYAN,D.A.; ZEIJTS,J.; WHITE,K.S.; WITHERSPOON,S.

    1999-03-29

    Many traditional control systems include a distributed collection of front end machines to control hardware. Back end tools are used to view, modify, and record the signals generated by these front end machines. Software servers, which are a middleware layer between the front and back ends, can improve a control system in several ways. Servers can enable on-line processing of raw data, and consolidation of functionality. In many cases data retrieved from the front end must be processed in order to convert the raw data into useful information. These calculations are often redundantly performed by different programs, frequently offline. Servers can monitor the raw data and rapidly perform calculations, producing new signals which can be treated like any other control system signal, and can be used by any back end application. Algorithms can be incorporated to actively modify signal values in the control system based upon changes of other signals, essentially producing feedback in a control system. Servers thus increase the flexibility of a control system. Lastly, servers running on inexpensive UNIX workstations can relay or cache frequently needed information, reducing the load on front end hardware by functioning as concentrators. Rather than many back end tools connecting directly to the front end machines, increasing the work load of these machines, they instead connect to the server. Servers like those discussed above have been used successfully at the Thomas Jefferson National Accelerator Facility to provide functionality such as beam steering, fault monitoring, storage of machine parameters, and on-line data processing. The authors discuss the potential uses of such, servers, and share the results of work performed to date.

  3. A Model for Measuring Effectiveness of an Online Course

    ERIC Educational Resources Information Center

    Mashaw, Bijan

    2012-01-01

    As a result of this research, a quantitative model and a procedure have been developed to create an online mentoring effectiveness index (EI). To develop the model, mentoring and teaching effectiveness are defined, and then the constructs and factors of effectiveness are identified. The model's construction is based on the theory that…

  4. A Model for Measuring Effectiveness of an Online Course

    ERIC Educational Resources Information Center

    Mashaw, Bijan

    2012-01-01

    As a result of this research, a quantitative model and a procedure have been developed to create an online mentoring effectiveness index (EI). To develop the model, mentoring and teaching effectiveness are defined, and then the constructs and factors of effectiveness are identified. The model's construction is based on the theory that…

  5. Online Ph.D. Program Delivery Models and Student Success

    ERIC Educational Resources Information Center

    Jorissen, Shari L.; Keen, James P.; Riedel, Eric S.

    2015-01-01

    The purpose of this study was to provide information to an online university that offers Ph.D. programs in three formats: knowledge area modules (or KAM, a type of faculty-led, self-directed doctoral study), course-based model, and mixed model (a combination of the KAM and course-based models). The investigators sought to determine why students…

  6. CentiServer: A Comprehensive Resource, Web-Based Application and R Package for Centrality Analysis.

    PubMed

    Jalili, Mahdi; Salehzadeh-Yazdi, Ali; Asgari, Yazdan; Arab, Seyed Shahriar; Yaghmaie, Marjan; Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran

    2015-01-01

    Various disciplines are trying to solve one of the most noteworthy queries and broadly used concepts in biology, essentiality. Centrality is a primary index and a promising method for identifying essential nodes, particularly in biological networks. The newly created CentiServer is a comprehensive online resource that provides over 110 definitions of different centrality indices, their computational methods, and algorithms in the form of an encyclopedia. In addition, CentiServer allows users to calculate 55 centralities with the help of an interactive web-based application tool and provides a numerical result as a comma separated value (csv) file format or a mapped graphical format as a graph modeling language (GML) file. The standalone version of this application has been developed in the form of an R package. The web-based application (CentiServer) and R package (centiserve) are freely available at http://www.centiserver.org/.

  7. CentiServer: A Comprehensive Resource, Web-Based Application and R Package for Centrality Analysis

    PubMed Central

    Jalili, Mahdi; Salehzadeh-Yazdi, Ali; Asgari, Yazdan; Arab, Seyed Shahriar; Yaghmaie, Marjan; Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran

    2015-01-01

    Various disciplines are trying to solve one of the most noteworthy queries and broadly used concepts in biology, essentiality. Centrality is a primary index and a promising method for identifying essential nodes, particularly in biological networks. The newly created CentiServer is a comprehensive online resource that provides over 110 definitions of different centrality indices, their computational methods, and algorithms in the form of an encyclopedia. In addition, CentiServer allows users to calculate 55 centralities with the help of an interactive web-based application tool and provides a numerical result as a comma separated value (csv) file format or a mapped graphical format as a graph modeling language (GML) file. The standalone version of this application has been developed in the form of an R package. The web-based application (CentiServer) and R package (centiserve) are freely available at http://www.centiserver.org/ PMID:26571275

  8. Catalytic site identification--a web server to identify catalytic site structural matches throughout PDB.

    PubMed

    Kirshner, Daniel A; Nilmeier, Jerome P; Lightstone, Felice C

    2013-07-01

    The catalytic site identification web server provides the innovative capability to find structural matches to a user-specified catalytic site among all Protein Data Bank proteins rapidly (in less than a minute). The server also can examine a user-specified protein structure or model to identify structural matches to a library of catalytic sites. Finally, the server provides a database of pre-calculated matches between all Protein Data Bank proteins and the library of catalytic sites. The database has been used to derive a set of hypothesized novel enzymatic function annotations. In all cases, matches and putative binding sites (protein structure and surfaces) can be visualized interactively online. The website can be accessed at http://catsid.llnl.gov.

  9. Use of Restraints from Consensus Fragments of Multiple Server Models To Enhance Protein-Structure Prediction Capability of the UNRES Force Field.

    PubMed

    Mozolewska, Magdalena A; Krupa, Paweł; Zaborowski, Bartłomiej; Liwo, Adam; Lee, Jooyoung; Joo, Keehyoung; Czaplewski, Cezary

    2016-11-28

    Recently, we developed a new approach to protein-structure prediction, which combines template-based modeling with the physics-based coarse-grained UNited RESidue (UNRES) force field. In this approach, restrained multiplexed replica exchange molecular dynamics simulations with UNRES, with the C(α)-distance and virtual-bond-dihedral-angle restraints derived from knowledge-based models are carried out. In this work, we report a test of this approach in the 11th Community Wide Experiment on the Critical Assessment of Techniques for Protein Structure Prediction (CASP11), in which we used the template-based models from early-stage predictions by the LEE group CASP11 server (group 038, called "nns"), and further improvement of the method. The quality of the models obtained in CASP11 was better than that resulting from unrestrained UNRES simulations; however, the obtained models were generally worse than the final nns models. Calculations with the final nns models, performed after CASP11, resulted in substantial improvement, especially for multi-domain proteins. Based on these results, we modified the procedure by deriving restraints from models from multiple servers, in this study the four top-performing servers in CASP11 (nns, BAKER-ROSETTASERVER, Zhang-server, and QUARK), and implementing either all restraints or only the restraints on the fragments that appear similar in the majority of models (the consensus fragments), outlier models discarded. Tests with 29 CASP11 human-prediction targets with length less than 400 amino-acid residues demonstrated that the consensus-fragment approach gave better results, i.e., lower α-carbon root-mean-square deviation from the experimental structures, higher template modeling score, and global distance test total score values than the best of the parent server models. Apart from global improvement (repacking and improving the orientation of domains and other substructures), improvement was also reached for template-based modeling

  10. A last updating evolution model for online social networks

    NASA Astrophysics Data System (ADS)

    Bu, Zhan; Xia, Zhengyou; Wang, Jiandong; Zhang, Chengcui

    2013-05-01

    As information technology has advanced, people are turning to electronic media more frequently for communication, and social relationships are increasingly found on online channels. However, there is very limited knowledge about the actual evolution of the online social networks. In this paper, we propose and study a novel evolution network model with the new concept of “last updating time”, which exists in many real-life online social networks. The last updating evolution network model can maintain the robustness of scale-free networks and can improve the network reliance against intentional attacks. What is more, we also found that it has the “small-world effect”, which is the inherent property of most social networks. Simulation experiment based on this model show that the results and the real-life data are consistent, which means that our model is valid.

  11. Optimal allocation of file servers in a local network environment

    NASA Technical Reports Server (NTRS)

    Woodside, C. M.; Tripathi, S. K.

    1986-01-01

    Files associated with workstations in a local area network are to be allocated among two or more file servers. Assuming statistically identical workstations and file servers and a performance model which is a closed multiclass separable queueing network, an optimal allocation is found. It is shown that all the files of each workstation should be placed on one file server, with the workstations divided as equally as possible among the file servers.

  12. LocExpress: a web server for efficiently estimating expression of novel transcripts.

    PubMed

    Hou, Mei; Tian, Feng; Jiang, Shuai; Kong, Lei; Yang, Dechang; Gao, Ge

    2016-12-22

    The temporal and spatial-specific expression pattern of a transcript in multiple tissues and cell types can indicate key clues about its function. While several gene atlas available online as pre-computed databases for known gene models, it's still challenging to get expression profile for previously uncharacterized (i.e. novel) transcripts efficiently. Here we developed LocExpress, a web server for efficiently estimating expression of novel transcripts across multiple tissues and cell types in human (20 normal tissues/cells types and 14 cell lines) as well as in mouse (24 normal tissues/cell types and nine cell lines). As a wrapper to RNA-Seq quantification algorithm, LocExpress efficiently reduces the time cost by making abundance estimation calls increasingly within the minimum spanning bundle region of input transcripts. For a given novel gene model, such local context-oriented strategy allows LocExpress to estimate its FPKMs in hundreds of samples within minutes on a standard Linux box, making an online web server possible. To the best of our knowledge, LocExpress is the only web server to provide nearly real-time expression estimation for novel transcripts in common tissues and cell types. The server is publicly available at http://loc-express.cbi.pku.edu.cn .

  13. FULLY COUPLED "ONLINE" CHEMISTRY WITHIN THE WRF MODEL

    EPA Science Inventory

    A fully coupled "online" Weather Research and Forecasting/Chemistry (WRF/Chem) model has been developed. The air quality component of the model is fully consistent with the meteorological component; both components use the same transport scheme (mass and scalar preserving), the s...

  14. FULLY COUPLED "ONLINE" CHEMISTRY WITHIN THE WRF MODEL

    EPA Science Inventory

    A fully coupled "online" Weather Research and Forecasting/Chemistry (WRF/Chem) model has been developed. The air quality component of the model is fully consistent with the meteorological component; both components use the same transport scheme (mass and scalar preserving), the s...

  15. Multi-perspective workflow modeling for online surgical situation models.

    PubMed

    Franke, Stefan; Meixensberger, Jürgen; Neumuth, Thomas

    2015-04-01

    Surgical workflow management is expected to enable situation-aware adaptation and intelligent systems behavior in an integrated operating room (OR). The overall aim is to unburden the surgeon and OR staff from both manual maintenance and information seeking tasks. A major step toward intelligent systems behavior is a stable classification of the surgical situation from multiple perspectives based on performed low-level tasks. The present work proposes a method for the classification of surgical situations based on multi-perspective workflow modeling. A model network that interconnects different types of surgical process models is described. Various aspects of a surgical situation description were considered: low-level tasks, high-level tasks, patient status, and the use of medical devices. A study with sixty neurosurgical interventions was conducted to evaluate the performance of our approach and its robustness against incomplete workflow recognition input. A correct classification rate of over 90% was measured for high-level tasks and patient status. The device usage models for navigation and neurophysiology classified over 95% of the situations correctly, whereas the ultrasound usage was more difficult to predict. Overall, the classification rate decreased with an increasing level of input distortion. Autonomous adaptation of medical devices and intelligent systems behavior do not currently depend solely on low-level tasks. Instead, they require a more general type of understanding of the surgical condition. The integration of various surgical process models in a network provided a comprehensive representation of the interventions and allowed for the generation of extensive situation descriptions. Multi-perspective surgical workflow modeling and online situation models will be a significant pre-requisite for reliable and intelligent systems behavior. Hence, they will contribute to a cooperative OR environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Bolstering the Quality and Integrity of Online Collaborative University-Level Courses via an Open Sim Standalone Server in Conjunction with Sloodle

    ERIC Educational Resources Information Center

    Pellas, Nikolaos

    2016-01-01

    The contemporary era provides several challenges which extend from the reconstitution of an innovative knowledge domain and curricula to candidate learning platforms that support online course delivery methods. Educators and scholars on these demands have recently started to rethink alternative ways for the assimilation of the experiential…

  17. Bolstering the Quality and Integrity of Online Collaborative University-Level Courses via an Open Sim Standalone Server in Conjunction with Sloodle

    ERIC Educational Resources Information Center

    Pellas, Nikolaos

    2016-01-01

    The contemporary era provides several challenges which extend from the reconstitution of an innovative knowledge domain and curricula to candidate learning platforms that support online course delivery methods. Educators and scholars on these demands have recently started to rethink alternative ways for the assimilation of the experiential…

  18. AquaSAXS: a web server for computation and fitting of SAXS profiles with non-uniformally hydrated atomic models

    PubMed Central

    Poitevin, Frédéric; Orland, Henri; Doniach, Sebastian; Koehl, Patrice; Delarue, Marc

    2011-01-01

    Small Angle X-ray Scattering (SAXS) techniques are becoming more and more useful for structural biologists and biochemists, thanks to better access to dedicated synchrotron beamlines, better detectors and the relative easiness of sample preparation. The ability to compute the theoretical SAXS profile of a given structural model, and to compare this profile with the measured scattering intensity, yields crucial structural informations about the macromolecule under study and/or its complexes in solution. An important contribution to the profile, besides the macromolecule itself and its solvent-excluded volume, is the excess density due to the hydration layer. AquaSAXS takes advantage of recently developed methods, such as AquaSol, that give the equilibrium solvent density map around macromolecules, to compute an accurate SAXS/WAXS profile of a given structure and to compare it to the experimental one. Here, we describe the interface architecture and capabilities of the AquaSAXS web server (http://lorentz.dynstr.pasteur.fr/aquasaxs.php). PMID:21665925

  19. Performance of a distributed superscalar storage server

    NASA Technical Reports Server (NTRS)

    Finestead, Arlan; Yeager, Nancy

    1993-01-01

    The RS/6000 performed well in our test environment. The potential exists for the RS/6000 to act as a departmental server for a small number of users, rather than as a high speed archival server. Multiple UniTree Disk Server's utilizing one UniTree Disk Server's utilizing one UniTree Name Server could be developed that would allow for a cost effective archival system. Our performance tests were clearly limited by the network bandwidth. The performance gathered by the LibUnix testing shows that UniTree is capable of exceeding ethernet speeds on an RS/6000 Model 550. The performance of FTP might be significantly faster if asked to perform across a higher bandwidth network. The UniTree Name Server also showed signs of being a potential bottleneck. UniTree sites that would require a high ratio of file creations and deletions to reads and writes would run into this bottleneck. It is possible to improve the UniTree Name Server performance by bypassing the UniTree LibUnix Library altogether and communicating directly with the UniTree Name Server and optimizing creations. Although testing was performed in a less than ideal environment, hopefully the performance statistics stated in this paper will give end-users a realistic idea as to what performance they can expect in this type of setup.

  20. R3D Align web server for global nucleotide to nucleotide alignments of RNA 3D structures

    PubMed Central

    Rahrig, Ryan R.; Petrov, Anton I.; Leontis, Neocles B.; Zirbel, Craig L.

    2013-01-01

    The R3D Align web server provides online access to ‘RNA 3D Align’ (R3D Align), a method for producing accurate nucleotide-level structural alignments of RNA 3D structures. The web server provides a streamlined and intuitive interface, input data validation and output that is more extensive and easier to read and interpret than related servers. The R3D Align web server offers a unique Gallery of Featured Alignments, providing immediate access to pre-computed alignments of large RNA 3D structures, including all ribosomal RNAs, as well as guidance on effective use of the server and interpretation of the output. By accessing the non-redundant lists of RNA 3D structures provided by the Bowling Green State University RNA group, R3D Align connects users to structure files in the same equivalence class and the best-modeled representative structure from each group. The R3D Align web server is freely accessible at http://rna.bgsu.edu/r3dalign/. PMID:23716643

  1. Comparison of Hydroxocobalamin Versus Norepinephrine Versus Saline in a Swine Model of Servere Septic Shock

    DTIC Science & Technology

    2016-05-20

    Versus Saline in a Swine Model of Severe Septic Shock presented at/published to SURF Conference, San Antonio, TX 20 May 2016 with MDWJ 41-108, and has...PRESENTED: Comparison of hydroxocobalamin versus norepinephrine versus saline in a Swine model of severe septic shock 7. FUNDING RECEIVED FOR THIS...Comparison of hydroxocbalamin versus norepinephrine versus saline in a swine model of severe septic shock. Background: Sepsis is associated with a mortality

  2. A Performance-Based Development Model for Online Faculty

    ERIC Educational Resources Information Center

    Fang, Berlin

    2007-01-01

    Faculty development in distance education does not happen in a vacuum. It is often interwoven with efforts to increase adoption of distance education programs and increase the effectiveness of online teaching. Training might not be the only way to meet these needs. This article presents a new faculty-development model, based on a systematic…

  3. A Distributed Online Curriculum and Courseware Development Model

    ERIC Educational Resources Information Center

    Durdu, Pinar Onay; Yalabik, Nese; Cagiltay, Kursat

    2009-01-01

    A distributed online curriculum and courseware development model (DONC[superscript 2]) is developed and tested in this study. Courseware development teams which may work in different institutions who need to develop high quality, reduced cost, on time products will be the users of DONC[superscript 2]. The related features from the disciplines of…

  4. Collaborative Online Teaching: A Model for Gerontological Social Work Education

    ERIC Educational Resources Information Center

    Fulton, Amy E.; Walsh, Christine A.; Azulai, Anna; Gulbrandsen, Cari; Tong, Hongmei

    2015-01-01

    Social work students and faculty are increasingly embracing online education and collaborative teaching. Yet models to support these activities have not been adequately developed. This paper describes how a team of instructors developed, delivered, and evaluated an undergraduate gerontological social work course using a collaborative online…

  5. Online prediction model based on the SVD-KPCA method.

    PubMed

    Elaissi, Ilyes; Jaffel, Ines; Taouali, Okba; Messaoud, Hassani

    2013-01-01

    This paper proposes a new method for online identification of a nonlinear system modelled on Reproducing Kernel Hilbert Space (RKHS). The proposed SVD-KPCA method uses the Singular Value Decomposition (SVD) technique to update the principal components. Then we use the Reduced Kernel Principal Component Analysis (RKPCA) to approach the principal components which represent the observations selected by the KPCA method.

  6. How Librarians Shape Online Courses: New Models and Partnerships

    ERIC Educational Resources Information Center

    Laverty, Corinne; Stockley, Denise

    2005-01-01

    Online course delivery can be a dynamic learning experience where information is used to shape and extend thinking. The challenge is creating a virtual classroom that combines evocative resources with tasks that enhance and stimulate student learning. New models are needed to reflect the changing learning environment that began with the advent of…

  7. Building a Model Explaining the Social Nature of Online Learning

    ERIC Educational Resources Information Center

    Tsai, I-Chun; Kim, Bosung; Liu, Pei-Ju; Goggins, Sean P.; Kumalasari, Christiana; Laffey, James M.

    2008-01-01

    Based on a framework emphasizing the social nature of learning, this research examines a model of how social constructs affect satisfaction within online learning using path analysis for students in higher education. The social constructs evaluated in this study include sense of community (SOC), social ability (SA), perceived ease of use (PEU) and…

  8. The Divine Pedagogy as a Model for Online Education

    ERIC Educational Resources Information Center

    Gresham, John

    2006-01-01

    In addition to the pragmatic concerns that often drive the use of technology in theological education, there is a need to develop theological justification and direction for online education. Several Roman Catholic Church documents propose the "divine pedagogy," the manner in which God teaches the human race, as a model for catechesis or religious…

  9. Keeping Our Network Safe: A Model of Online Protection Behaviour

    ERIC Educational Resources Information Center

    Lee, Doohwang; Larose, Robert; Rifon, Nora

    2008-01-01

    The objective of this study is to develop and test a model of online protection behaviour, particularly regarding the use of virus protection. Hypotheses are proposed concerning the predictors of the intention to engage in virus protection behaviour. Using a survey of 273 college students who use the Internet, a test of the hypotheses is conducted…

  10. A Distributed Online Curriculum and Courseware Development Model

    ERIC Educational Resources Information Center

    Durdu, Pinar Onay; Yalabik, Nese; Cagiltay, Kursat

    2009-01-01

    A distributed online curriculum and courseware development model (DONC[superscript 2]) is developed and tested in this study. Courseware development teams which may work in different institutions who need to develop high quality, reduced cost, on time products will be the users of DONC[superscript 2]. The related features from the disciplines of…

  11. Improving Learning and Reducing Costs: New Models for Online Learning.

    ERIC Educational Resources Information Center

    Twigg, Carol A.

    2003-01-01

    Describes five course redesign models (supplemental, replacement, emporium, fully online, and buffet) used by grantees of the Program in Course Redesign sponsored by the Pew Charitable Trusts. The grants helped colleges redesign instruction using technology to achieve quality enhancements as well as cost savings. (EV)

  12. Building a Model Explaining the Social Nature of Online Learning

    ERIC Educational Resources Information Center

    Tsai, I-Chun; Kim, Bosung; Liu, Pei-Ju; Goggins, Sean P.; Kumalasari, Christiana; Laffey, James M.

    2008-01-01

    Based on a framework emphasizing the social nature of learning, this research examines a model of how social constructs affect satisfaction within online learning using path analysis for students in higher education. The social constructs evaluated in this study include sense of community (SOC), social ability (SA), perceived ease of use (PEU) and…

  13. Keeping Our Network Safe: A Model of Online Protection Behaviour

    ERIC Educational Resources Information Center

    Lee, Doohwang; Larose, Robert; Rifon, Nora

    2008-01-01

    The objective of this study is to develop and test a model of online protection behaviour, particularly regarding the use of virus protection. Hypotheses are proposed concerning the predictors of the intention to engage in virus protection behaviour. Using a survey of 273 college students who use the Internet, a test of the hypotheses is conducted…

  14. Designing a Predictive Model of Student Satisfaction in Online Learning

    ERIC Educational Resources Information Center

    Parahoo, Sanjai K; Santally, Mohammad Issack; Rajabalee, Yousra; Harvey, Heather Lea

    2016-01-01

    Higher education institutions consider student satisfaction to be one of the major elements in determining the quality of their programs. The objective of the study was to develop a model of student satisfaction to identify the influencers that emerged in online higher education settings. The study adopted a mixed method approach to identify…

  15. Subject Access in Online Catalogs: A Design Model.

    ERIC Educational Resources Information Center

    Bates, Marcia J.

    1986-01-01

    Presents a model for the design of online catalog subject access based on three principles: the uncertainty of subject indexing, the need for greater variety in searcher's queries, and the complexity of the search process. The proposed system is based on existing Library of Congress subject cataloging. (EM)

  16. Collaborative Online Teaching: A Model for Gerontological Social Work Education

    ERIC Educational Resources Information Center

    Fulton, Amy E.; Walsh, Christine A.; Azulai, Anna; Gulbrandsen, Cari; Tong, Hongmei

    2015-01-01

    Social work students and faculty are increasingly embracing online education and collaborative teaching. Yet models to support these activities have not been adequately developed. This paper describes how a team of instructors developed, delivered, and evaluated an undergraduate gerontological social work course using a collaborative online…

  17. A Performance-Based Development Model for Online Faculty

    ERIC Educational Resources Information Center

    Fang, Berlin

    2007-01-01

    Faculty development in distance education does not happen in a vacuum. It is often interwoven with efforts to increase adoption of distance education programs and increase the effectiveness of online teaching. Training might not be the only way to meet these needs. This article presents a new faculty-development model, based on a systematic…

  18. Designing a Predictive Model of Student Satisfaction in Online Learning

    ERIC Educational Resources Information Center

    Parahoo, Sanjai K; Santally, Mohammad Issack; Rajabalee, Yousra; Harvey, Heather Lea

    2016-01-01

    Higher education institutions consider student satisfaction to be one of the major elements in determining the quality of their programs. The objective of the study was to develop a model of student satisfaction to identify the influencers that emerged in online higher education settings. The study adopted a mixed method approach to identify…

  19. Modeling Periodic Impulsive Effects on Online TV Series Diffusion

    PubMed Central

    Fang, Qiwen; Wang, Xi

    2016-01-01

    Background Online broadcasting substantially affects the production, distribution, and profit of TV series. In addition, online word-of-mouth significantly affects the diffusion of TV series. Because on-demand streaming rates are the most important factor that influences the earnings of online video suppliers, streaming statistics and forecasting trends are valuable. In this paper, we investigate the effects of periodic impulsive stimulation and pre-launch promotion on on-demand streaming dynamics. We consider imbalanced audience feverish distribution using an impulsive susceptible-infected-removed(SIR)-like model. In addition, we perform a correlation analysis of online buzz volume based on Baidu Index data. Methods We propose a PI-SIR model to evolve audience dynamics and translate them into on-demand streaming fluctuations, which can be observed and comprehended by online video suppliers. Six South Korean TV series datasets are used to test the model. We develop a coarse-to-fine two-step fitting scheme to estimate the model parameters, first by fitting inter-period accumulation and then by fitting inner-period feverish distribution. Results We find that audience members display similar viewing habits. That is, they seek new episodes every update day but fade away. This outcome means that impulsive intensity plays a crucial role in on-demand streaming diffusion. In addition, the initial audience size and online buzz are significant factors. On-demand streaming fluctuation is highly correlated with online buzz fluctuation. Conclusion To stimulate audience attention and interpersonal diffusion, it is worthwhile to invest in promotion near update days. Strong pre-launch promotion is also a good marketing tool to improve overall performance. It is not advisable for online video providers to promote several popular TV series on the same update day. Inter-period accumulation is a feasible forecasting tool to predict the future trend of the on-demand streaming amount

  20. Modeling Periodic Impulsive Effects on Online TV Series Diffusion.

    PubMed

    Fu, Peihua; Zhu, Anding; Fang, Qiwen; Wang, Xi

    Online broadcasting substantially affects the production, distribution, and profit of TV series. In addition, online word-of-mouth significantly affects the diffusion of TV series. Because on-demand streaming rates are the most important factor that influences the earnings of online video suppliers, streaming statistics and forecasting trends are valuable. In this paper, we investigate the effects of periodic impulsive stimulation and pre-launch promotion on on-demand streaming dynamics. We consider imbalanced audience feverish distribution using an impulsive susceptible-infected-removed(SIR)-like model. In addition, we perform a correlation analysis of online buzz volume based on Baidu Index data. We propose a PI-SIR model to evolve audience dynamics and translate them into on-demand streaming fluctuations, which can be observed and comprehended by online video suppliers. Six South Korean TV series datasets are used to test the model. We develop a coarse-to-fine two-step fitting scheme to estimate the model parameters, first by fitting inter-period accumulation and then by fitting inner-period feverish distribution. We find that audience members display similar viewing habits. That is, they seek new episodes every update day but fade away. This outcome means that impulsive intensity plays a crucial role in on-demand streaming diffusion. In addition, the initial audience size and online buzz are significant factors. On-demand streaming fluctuation is highly correlated with online buzz fluctuation. To stimulate audience attention and interpersonal diffusion, it is worthwhile to invest in promotion near update days. Strong pre-launch promotion is also a good marketing tool to improve overall performance. It is not advisable for online video providers to promote several popular TV series on the same update day. Inter-period accumulation is a feasible forecasting tool to predict the future trend of the on-demand streaming amount. The buzz in public social communities

  1. A simple generative model of collective online behavior.

    PubMed

    Gleeson, James P; Cellai, Davide; Onnela, Jukka-Pekka; Porter, Mason A; Reed-Tsochas, Felix

    2014-07-22

    Human activities increasingly take place in online environments, providing novel opportunities for relating individual behaviors to population-level outcomes. In this paper, we introduce a simple generative model for the collective behavior of millions of social networking site users who are deciding between different software applications. Our model incorporates two distinct mechanisms: one is associated with recent decisions of users, and the other reflects the cumulative popularity of each application. Importantly, although various combinations of the two mechanisms yield long-time behavior that is consistent with data, the only models that reproduce the observed temporal dynamics are those that strongly emphasize the recent popularity of applications over their cumulative popularity. This demonstrates--even when using purely observational data without experimental design--that temporal data-driven modeling can effectively distinguish between competing microscopic mechanisms, allowing us to uncover previously unidentified aspects of collective online behavior.

  2. Submersed Aquatic Vegetation Modeling Output Online

    USGS Publications Warehouse

    Yin, Yao; Rogala, Jim; Sullivan, John; Rohweder, Jason J.

    2005-01-01

    Introduction The ability to predict the distribution of submersed aquatic vegetation in the Upper Mississippi River on the basis of physical or chemical variables is useful to resource managers. Wildlife managers have a keen interest in advanced estimates of food quantity such as American wildcelery (Vallisneria americana) population status to give out more informed advisories to hunters before the fall hunting season. Predictions for distribution of submerged aquatic vegetation beds can potentially increase hunter observance of voluntary avoidance zones where foraging birds are left alone to feed undisturbed. In years when submersed aquatic vegetation is predicted to be scarce in important wildlife habitats, managers can get the message out to hunters well before the hunting season (Jim Nissen, Upper Mississippi River National Wildlife and Fish Refuge, La Crosse District Manager, La Crosse, Wisconsin, personal communication). We developed a statistical model to predict the probability of occurrence of submersed aquatic vegetation in Pool 8 of the Upper Mississippi River on the basis of a few hydrological, physical, and geomorphic variables. Our model takes into consideration flow velocity, wind fetch, bathymetry, growing-season daily water level, and light extinction coefficient in the river (fig. 1) and calculates the probability of submersed aquatic vegetation existence in Pool 8 in individual 5- x 5-m grid cells. The model was calibrated using the data collected in 1998 (516 sites), 1999 (595 sites), and 2000 (649 sites) using a stratified random sampling protocol (Yin and others, 2000b). To validate the model, we chose the data from the Long Term Resource Monitoring Program (LTRMP) transect sampling in backwater areas (Rogers and Owens 1995; Yin and others, 2000a) and ran the model for each 5- x 5-m grid cell in every growing season from 1991 to 2001. We tallied all the cells and came up with an annual average percent frequency of submersed aquatic vegetation

  3. Online Knowledge-Based Model for Big Data Topic Extraction

    PubMed Central

    Khan, Muhammad Taimoor; Durrani, Mehr; Khalid, Shehzad; Aziz, Furqan

    2016-01-01

    Lifelong machine learning (LML) models learn with experience maintaining a knowledge-base, without user intervention. Unlike traditional single-domain models they can easily scale up to explore big data. The existing LML models have high data dependency, consume more resources, and do not support streaming data. This paper proposes online LML model (OAMC) to support streaming data with reduced data dependency. With engineering the knowledge-base and introducing new knowledge features the learning pattern of the model is improved for data arriving in pieces. OAMC improves accuracy as topic coherence by 7% for streaming data while reducing the processing cost to half. PMID:27195004

  4. A Comparison Between Publish-and-Subscribe and Client-Server Models in Distributed Control System Networks

    NASA Technical Reports Server (NTRS)

    Boulanger, Richard P., Jr.; Kwauk, Xian-Min; Stagnaro, Mike; Kliss, Mark (Technical Monitor)

    1998-01-01

    The BIO-Plex control system requires real-time, flexible, and reliable data delivery. There is no simple "off-the-shelf 'solution. However, several commercial packages will be evaluated using a testbed at ARC for publish- and-subscribe and client-server communication architectures. Point-to-point communication architecture is not suitable for real-time BIO-Plex control system. Client-server architecture provides more flexible data delivery. However, it does not provide direct communication among nodes on the network. Publish-and-subscribe implementation allows direct information exchange among nodes on the net, providing the best time-critical communication. In this work Network Data Delivery Service (NDDS) from Real-Time Innovations, Inc. ARTIE will be used to implement publish-and subscribe architecture. It offers update guarantees and deadlines for real-time data delivery. Bridgestone, a data acquisition and control software package from National Instruments, will be tested for client-server arrangement. A microwave incinerator located at ARC will be instrumented with a fieldbus network of control devices. BridgeVIEW will be used to implement an enterprise server. An enterprise network consisting of several nodes at ARC and a WAN connecting ARC and RISC will then be setup to evaluate proposed control system architectures. Several network configurations will be evaluated for fault tolerance, quality of service, reliability and efficiency. Data acquired from these network evaluation tests will then be used to determine preliminary design criteria for the BIO-Plex distributed control system.

  5. A Comparison Between Publish-and-Subscribe and Client-Server Models in Distributed Control System Networks

    NASA Technical Reports Server (NTRS)

    Boulanger, Richard P., Jr.; Kwauk, Xian-Min; Stagnaro, Mike; Kliss, Mark (Technical Monitor)

    1998-01-01

    The BIO-Plex control system requires real-time, flexible, and reliable data delivery. There is no simple "off-the-shelf 'solution. However, several commercial packages will be evaluated using a testbed at ARC for publish- and-subscribe and client-server communication architectures. Point-to-point communication architecture is not suitable for real-time BIO-Plex control system. Client-server architecture provides more flexible data delivery. However, it does not provide direct communication among nodes on the network. Publish-and-subscribe implementation allows direct information exchange among nodes on the net, providing the best time-critical communication. In this work Network Data Delivery Service (NDDS) from Real-Time Innovations, Inc. ARTIE will be used to implement publish-and subscribe architecture. It offers update guarantees and deadlines for real-time data delivery. Bridgestone, a data acquisition and control software package from National Instruments, will be tested for client-server arrangement. A microwave incinerator located at ARC will be instrumented with a fieldbus network of control devices. BridgeVIEW will be used to implement an enterprise server. An enterprise network consisting of several nodes at ARC and a WAN connecting ARC and RISC will then be setup to evaluate proposed control system architectures. Several network configurations will be evaluated for fault tolerance, quality of service, reliability and efficiency. Data acquired from these network evaluation tests will then be used to determine preliminary design criteria for the BIO-Plex distributed control system.

  6. Data Transfer Software-SAS MetaData Server & Phoenix Integration Model Center

    SciTech Connect

    2010-04-15

    This software is a plug-in that interfaces between the Phoenix Integration's Model Center and the Base SAS 9.2 applications. The end use of the plug-in is to link input and output data that resides in SAS tables or MS SQL to and from "legacy" software programs without recoding. The potential end users are users who need to run legacy code and want data stored in a SQL database.

  7. Mobile agent based online integration modeling for traffic information services

    NASA Astrophysics Data System (ADS)

    Li, Qingquan; Gao, Dequan; Fang, Zhixiang; Li, Lianying

    2007-06-01

    With the rapid development of urban economy and urbanization construction in China, traffic load rises sharply because of the larger vehicle occupancy within many urban areas, which has already led to serious traffic congestion problem. GIS-T is an efficient technological solution and core information infrastructure for solving modern urban transportation problems. High-level traffic systems must integrate real-time traffic information and spatial data of road to supply timely and efficient public services and guarantee a better orderly transportation. However, for traffic information is multisource, complex and massive, traffic information service must have fast, powerful capabilities for online integration processing. Online integration of traffic information emphasizes the traffic resources share and services optimization, and solve assignment, scheduling, monitoring and feedback of integration computing tasks in dynamic and distributed network. This paper firstly analyzes traffic data and existing problems of online integration, and then discusses mobile agent technology, and finally proposes a mobile agent based unified online integration model of traffic information. This model will achieve cooperative computing and more accessible, flexible and reliable traffic information services.

  8. Characterizing and modeling the dynamics of online popularity.

    PubMed

    Ratkiewicz, Jacob; Fortunato, Santo; Flammini, Alessandro; Menczer, Filippo; Vespignani, Alessandro

    2010-10-08

    Online popularity has an enormous impact on opinions, culture, policy, and profits. We provide a quantitative, large scale, temporal analysis of the dynamics of online content popularity in two massive model systems: the Wikipedia and an entire country's Web space. We find that the dynamics of popularity are characterized by bursts, displaying characteristic features of critical systems such as fat-tailed distributions of magnitude and interevent time. We propose a minimal model combining the classic preferential popularity increase mechanism with the occurrence of random popularity shifts due to exogenous factors. The model recovers the critical features observed in the empirical analysis of the systems analyzed here, highlighting the key factors needed in the description of popularity dynamics.

  9. Antibody modeling using the prediction of immunoglobulin structure (PIGS) web server [corrected].

    PubMed

    Marcatili, Paolo; Olimpieri, Pier Paolo; Chailyan, Anna; Tramontano, Anna

    2014-12-01

    Antibodies (or immunoglobulins) are crucial for defending organisms from pathogens, but they are also key players in many medical, diagnostic and biotechnological applications. The ability to predict their structure and the specific residues involved in antigen recognition has several useful applications in all of these areas. Over the years, we have developed or collaborated in developing a strategy that enables researchers to predict the 3D structure of antibodies with a very satisfactory accuracy. The strategy is completely automated and extremely fast, requiring only a few minutes (∼10 min on average) to build a structural model of an antibody. It is based on the concept of canonical structures of antibody loops and on our understanding of the way light and heavy chains pack together.

  10. I-TASSER server: new development for protein structure and function predictions

    PubMed Central

    Yang, Jianyi; Zhang, Yang

    2015-01-01

    The I-TASSER server (http://zhanglab.ccmb.med.umich.edu/I-TASSER) is an online resource for automated protein structure prediction and structure-based function annotation. In I-TASSER, structural templates are first recognized from the PDB using multiple threading alignment approaches. Full-length structure models are then constructed by iterative fragment assembly simulations. The functional insights are finally derived by matching the predicted structure models with known proteins in the function databases. Although the server has been widely used for various biological and biomedical investigations, numerous comments and suggestions have been reported from the user community. In this article, we summarize recent developments on the I-TASSER server, which were designed to address the requirements from the user community and to increase the accuracy of modeling predictions. Focuses have been made on the introduction of new methods for atomic-level structure refinement, local structure quality estimation and biological function annotations. We expect that these new developments will improve the quality of the I-TASSER server and further facilitate its use by the community for high-resolution structure and function prediction. PMID:25883148

  11. A continuous available (CA) server for medical imaging applications.

    PubMed

    Huang, H K; Liu, Brent J; Zhou, Z

    2004-07-01

    The trend of medical imaging research and application is toward large database management and manipulation, which requires a robust image server to receive image data from sources and to deliver them to users reliably and in a timely fashion. This article describes the design, implementation, and clinical applications of a continuous available (CA) image server for these purposes. The design of the CA image server is based on the concept of a triple modular redundancy server with three redundant server modules. Coupled with a majority voting mechanism in the three modules and failover software, the triple modular redundancy server takes care of all single points of failure hardware components in the CA image server automatically to achieve fault tolerance. Methods and procedures of evaluating the fault tolerance system reliability caused by network connectivity, motherboard, and disk storage failures are described. Thorough experimental results in laboratory and clinical environments verify that the image server achieves 99.999% hardware up time (or 5 minutes/year down time), satisfying the industrial terminology of hardware continuous availability. Performance of failover of the CA image server is automatically tabulated during these procedures. Applications of CA image server are extensive. Two examples are given including Picture Archiving and Communication System, and off-site back-up archive using the Application Service Provider model. As designed, the CA image server is portable, scalable, affordable, easy to install, and requires no human intervention during failover and system recovery.

  12. The Bioinformatics Links Directory: a Compilation of Molecular Biology Web Servers

    PubMed Central

    Fox, Joanne A.; Butland, Stefanie L.; McMillan, Scott; Campbell, Graeme; Ouellette, B. F. Francis

    2005-01-01

    The Bioinformatics Links Directory is an online community resource that contains a directory of freely available tools, databases, and resources for bioinformatics and molecular biology research. The listing of the servers published in this and previous issues of Nucleic Acids Research together with other useful tools and websites represents a rich repository of resources that are openly provided to the research community using internet technologies. The 166 servers highlighted in the 2005 Web Server Issue are included in the more than 700 links to useful online resources that are currently contained within the descriptive biological categories of the Bioinformatics Links Directory. This curated listing of bioinformatics resources is available online at the Bioinformatics Links Directory web site, . A complete listing of the 2005 Nucleic Acids Research Web Server Issue servers is available online at the Nucleic Acids web site, , and on the Bioinformatics Links Directory web site, . PMID:15980476

  13. Developing the HTA core model for the online environment.

    PubMed

    Lampe, Kristian; Pasternack, Iris; Saarekas, Oskari; Raustia, Leena; Cleemput, Irina; Corio, Mirella; Endel, Gottfried; Frønsdal, Katrine; Imaz, Iñaki; Kleijnen, Sarah; Kristensen, Finn; Rüther, Alric; Werkö, Sophie; Cerbo, Marina

    2014-11-01

    A framework for collaborative production and sharing of HTA information, the HTA Core Model, was originally developed within EUnetHTA in 2006-08. In this paper, we describe the further development of the Model to allow implementation and utilization of the Model online. The aim was to capture a generic HTA process that would allow effective use of the HTA Core Model and resulting HTA information while at the same time not interfering with HTA agencies' internal processes. The work was coordinated by a development team in Finland, supported by an international expert group. Two pilot testing rounds were organized among EUnetHTA agencies and two extensive core HTA projects tested the tool in a real setting. The final work was also formally validated by a group of HTA agencies. The HTA Core Model Online--available at http://www.corehta.info--is a web site hosting a) a tool to allow electronic utilization of the HTA Core Model and b) a database of produced HTA information. While access to the HTA information is free to all, the production features are currently available to EUnetHTA member agencies only. A policy was crafted to steer the use of the Model and produced information. We have successfully enabled electronic use of the HTA Core Model and agreed on a policy for its utilization. The system is already being used in subsequent HTA projects within EUnetHTA Joint Action 2. Identified shortcomings and further needs will be addressed in subsequent development.

  14. The AtChem On-line model and Electronic Laboratory Notebook (ELN): A free community modelling tool with provenance capture

    NASA Astrophysics Data System (ADS)

    Young, J. C.; Boronska, K.; Martin, C. J.; Rickard, A. R.; Vázquez Moreno, M.; Pilling, M. J.; Haji, M. H.; Dew, P. M.; Lau, L. M.; Jimack, P. K.

    2010-12-01

    AtChem On-line1 is a simple to use zero-dimensional box modelling toolkit, developed for use by laboratory, field and chamber scientists. Any set of chemical reactions can be simulated, in particular the whole Master Chemical Mechanism (MCM2) or any subset of it. Parameters and initial data can be provided through a self-explanatory web form and the resulting model is compiled and run on a dedicated server. The core part of the toolkit, providing a robust solver for thousands of chemical reactions, is written in Fortran and uses SUNDIALS3 CVODE libraries. Chemical systems can be constrained at multiple, user-determined timescales; this enabled studies of radical chemistry at one minute timescales. AtChem On-line is free to use and requires no installation - a web browser, text editor and any compressing software is all the user needs. CPU and storage are provided by the server (input and output data are saved indefinitely). An off-line version is also being developed, which will provide batch processing, an advanced graphical user interface and post-processing tools, for example, Rate of Production Analysis (ROPA) and chainlength analysis. The source code is freely available for advanced users wishing to adapt and run the program locally. Data management, dissemination and archiving are essential in all areas of science. In order to do this in an efficient and transparent way, there is a critical need to capture high quality metadata/provenance for modelling activities. An Electronic Laboratory Notebook (ELN) has been developed in parallel with AtChem Online as part of the EC EUROCHAMP24 project. In order to use controlled chamber experiments to evaluate the MCM, we need to be able to archive, track and search information on all associated chamber model runs, so that they can be used in subsequent mechanism development. Therefore it would be extremely useful if experiment and model metadata/provenance could be easily and automatically stored electronically

  15. Home media server content management

    NASA Astrophysics Data System (ADS)

    Tokmakoff, Andrew A.; van Vliet, Harry

    2001-07-01

    With the advent of set-top boxes, the convergence of TV (broadcasting) and PC (Internet) is set to enter the home environment. Currently, a great deal of activity is occurring in developing standards (TV-Anytime Forum) and devices (TiVo) for local storage on Home Media Servers (HMS). These devices lie at the heart of convergence of the triad: communications/networks - content/media - computing/software. Besides massive storage capacity and being a communications 'gateway', the home media server is characterised by the ability to handle metadata and software that provides an easy to use on-screen interface and intelligent search/content handling facilities. In this paper, we describe a research prototype HMS that is being developed within the GigaCE project at the Telematica Instituut . Our prototype demonstrates advanced search and retrieval (video browsing), adaptive user profiling and an innovative 3D component of the Electronic Program Guide (EPG) which represents online presence. We discuss the use of MPEG-7 for representing metadata, the use of MPEG-21 working draft standards for content identification, description and rights expression, and the use of HMS peer-to-peer content distribution approaches. Finally, we outline explorative user behaviour experiments that aim to investigate the effectiveness of the prototype HMS during development.

  16. Remote diagnosis server

    NASA Technical Reports Server (NTRS)

    Deb, Somnath (Inventor); Ghoshal, Sudipto (Inventor); Malepati, Venkata N. (Inventor); Kleinman, David L. (Inventor); Cavanaugh, Kevin F. (Inventor)

    2004-01-01

    A network-based diagnosis server for monitoring and diagnosing a system, the server being remote from the system it is observing, comprises a sensor for generating signals indicative of a characteristic of a component of the system, a network-interfaced sensor agent coupled to the sensor for receiving signals therefrom, a broker module coupled to the network for sending signals to and receiving signals from the sensor agent, a handler application connected to the broker module for transmitting signals to and receiving signals therefrom, a reasoner application in communication with the handler application for processing, and responding to signals received from the handler application, wherein the sensor agent, broker module, handler application, and reasoner applications operate simultaneously relative to each other, such that the present invention diagnosis server performs continuous monitoring and diagnosing of said components of the system in real time. The diagnosis server is readily adaptable to various different systems.

  17. Online Statistical Modeling (Regression Analysis) for Independent Responses

    NASA Astrophysics Data System (ADS)

    Made Tirta, I.; Anggraeni, Dian; Pandutama, Martinus

    2017-06-01

    Regression analysis (statistical analmodelling) are among statistical methods which are frequently needed in analyzing quantitative data, especially to model relationship between response and explanatory variables. Nowadays, statistical models have been developed into various directions to model various type and complex relationship of data. Rich varieties of advanced and recent statistical modelling are mostly available on open source software (one of them is R). However, these advanced statistical modelling, are not very friendly to novice R users, since they are based on programming script or command line interface. Our research aims to developed web interface (based on R and shiny), so that most recent and advanced statistical modelling are readily available, accessible and applicable on web. We have previously made interface in the form of e-tutorial for several modern and advanced statistical modelling on R especially for independent responses (including linear models/LM, generalized linier models/GLM, generalized additive model/GAM and generalized additive model for location scale and shape/GAMLSS). In this research we unified them in the form of data analysis, including model using Computer Intensive Statistics (Bootstrap and Markov Chain Monte Carlo/ MCMC). All are readily accessible on our online Virtual Statistics Laboratory. The web (interface) make the statistical modeling becomes easier to apply and easier to compare them in order to find the most appropriate model for the data.

  18. A Hybrid Evaluation Model for Evaluating Online Professional Development

    ERIC Educational Resources Information Center

    Hahs-Vaughn, Debbie; Zygouris-Coe, Vicky; Fiedler, Rebecca

    2007-01-01

    Online professional development is multidimensional. It encompasses: a) an online, web-based format; b) professional development; and most likely c) specific objectives tailored to and created for the respective online professional development course. Evaluating online professional development is therefore also multidimensional and as such both…

  19. PEM public key certificate cache server

    NASA Astrophysics Data System (ADS)

    Cheung, T.

    1993-12-01

    Privacy Enhanced Mail (PEM) provides privacy enhancement services to users of Internet electronic mail. Confidentiality, authentication, message integrity, and non-repudiation of origin are provided by applying cryptographic measures to messages transferred between end systems by the Message Transfer System. PEM supports both symmetric and asymmetric key distribution. However, the prevalent implementation uses a public key certificate-based strategy, modeled after the X.509 directory authentication framework. This scheme provides an infrastructure compatible with X.509. According to RFC 1422, public key certificates can be stored in directory servers, transmitted via non-secure message exchanges, or distributed via other means. Directory services provide a specialized distributed database for OSI applications. The directory contains information about objects and then provides structured mechanisms for accessing that information. Since directory services are not widely available now, a good approach is to manage certificates in a centralized certificate server. This document describes the detailed design of a centralized certificate cache serve. This server manages a cache of certificates and a cache of Certificate Revocation Lists (CRL's) for PEM applications. PEMapplications contact the server to obtain/store certificates and CRL's. The server software is programmed in C and ELROS. To use this server, ISODE has to be configured and installed properly. The ISODE library 'libisode.a' has to be linked together with this library because ELROS uses the transport layer functions provided by 'libisode.a.' The X.500 DAP library that is included with the ELROS distribution has to be linked in also, since the server uses the DAP library functions to communicate with directory servers.

  20. ProBiS tools (algorithm, database, and web servers) for predicting and modeling of biologically interesting proteins.

    PubMed

    Konc, Janez; Janežič, Dušanka

    2017-09-01

    ProBiS (Protein Binding Sites) Tools consist of algorithm, database, and web servers for prediction of binding sites and protein ligands based on the detection of structurally similar binding sites in the Protein Data Bank. In this article, we review the operations that ProBiS Tools perform, provide comments on the evolution of the tools, and give some implementation details. We review some of its applications to biologically interesting proteins. ProBiS Tools are freely available at http://probis.cmm.ki.si and http://probis.nih.gov. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Simulation of Distributed Object Oriented Servers

    DTIC Science & Technology

    2003-12-01

    to the simulation model to enable the system designer to study the effect and expenses of adding memory , upgrading the CPU or adding addition...43 192 B. LINGO MODEL MODEL: SETS: MACHINE / Mozart Handel Beethoven /: MEMORY , SPEED; SERVER / A B C D E F G H I J...71 2. Effect of Weigh Model ........................................................... 73 F. CONCLUSION

  2. Online parameter estimation for surgical needle steering model.

    PubMed

    Yan, Kai Guo; Podder, Tarun; Xiao, Di; Yu, Yan; Liu, Tien-I; Ling, Keck Voon; Ng, Wan Sing

    2006-01-01

    Estimation of the system parameters, given noisy input/output data, is a major field in control and signal processing. Many different estimation methods have been proposed in recent years. Among various methods, Extended Kalman Filtering (EKF) is very useful for estimating the parameters of a nonlinear and time-varying system. Moreover, it can remove the effects of noises to achieve significantly improved results. Our task here is to estimate the coefficients in a spring-beam-damper needle steering model. This kind of spring-damper model has been adopted by many researchers in studying the tissue deformation. One difficulty in using such model is to estimate the spring and damper coefficients. Here, we proposed an online parameter estimator using EKF to solve this problem. The detailed design is presented in this paper. Computer simulations and physical experiments have revealed that the simulator can estimate the parameters accurately with fast convergent speed and improve the model efficacy.

  3. Fault tolerant system with imperfect coverage, reboot and server vacation

    NASA Astrophysics Data System (ADS)

    Jain, Madhu; Meena, Rakesh Kumar

    2016-12-01

    This study is concerned with the performance modeling of a fault tolerant system consisting of operating units supported by a combination of warm and cold spares. The on-line as well as warm standby units are subject to failures and are send for the repair to a repair facility having single repairman which is prone to failure. If the failed unit is not detected, the system enters into an unsafe state from which it is cleared by the reboot and recovery action. The server is allowed to go for vacation if there is no failed unit present in the system. Markov model is developed to obtain the transient probabilities associated with the system states. Runge-Kutta method is used to evaluate the system state probabilities and queueing measures. To explore the sensitivity and cost associated with the system, numerical simulation is conducted.

  4. Time dependent optimal switching controls in online selling models

    SciTech Connect

    Bradonjic, Milan; Cohen, Albert

    2010-01-01

    We present a method to incorporate dishonesty in online selling via a stochastic optimal control problem. In our framework, the seller wishes to maximize her average wealth level W at a fixed time T of her choosing. The corresponding Hamilton-Jacobi-Bellmann (HJB) equation is analyzed for a basic case. For more general models, the admissible control set is restricted to a jump process that switches between extreme values. We propose a new approach, where the optimal control problem is reduced to a multivariable optimization problem.

  5. A Model for Developing High-Quality Online Courses: Integrating a Systems Approach with Learning Theory

    ERIC Educational Resources Information Center

    Puzziferro, Maria; Shelton, Kaye

    2008-01-01

    As the demand for online education continues to increase, institutions are faced with developing process models for efficient, high-quality online course development. This paper describes a systems, team-based, approach that centers on an online instructional design theory ("Active Mastery Learning") implemented at Colorado State…

  6. An online model composition tool for system biology models

    PubMed Central

    2013-01-01

    Background There are multiple representation formats for Systems Biology computational models, and the Systems Biology Markup Language (SBML) is one of the most widely used. SBML is used to capture, store, and distribute computational models by Systems Biology data sources (e.g., the BioModels Database) and researchers. Therefore, there is a need for all-in-one web-based solutions that support advance SBML functionalities such as uploading, editing, composing, visualizing, simulating, querying, and browsing computational models. Results We present the design and implementation of the Model Composition Tool (Interface) within the PathCase-SB (PathCase Systems Biology) web portal. The tool helps users compose systems biology models to facilitate the complex process of merging systems biology models. We also present three tools that support the model composition tool, namely, (1) Model Simulation Interface that generates a visual plot of the simulation according to user’s input, (2) iModel Tool as a platform for users to upload their own models to compose, and (3) SimCom Tool that provides a side by side comparison of models being composed in the same pathway. Finally, we provide a web site that hosts BioModels Database models and a separate web site that hosts SBML Test Suite models. Conclusions Model composition tool (and the other three tools) can be used with little or no knowledge of the SBML document structure. For this reason, students or anyone who wants to learn about systems biology will benefit from the described functionalities. SBML Test Suite models will be a nice starting point for beginners. And, for more advanced purposes, users will able to access and employ models of the BioModels Database as well. PMID:24006914

  7. An online model composition tool for system biology models.

    PubMed

    Coskun, Sarp A; Cicek, A Ercument; Lai, Nicola; Dash, Ranjan K; Ozsoyoglu, Z Meral; Ozsoyoglu, Gultekin

    2013-09-05

    There are multiple representation formats for Systems Biology computational models, and the Systems Biology Markup Language (SBML) is one of the most widely used. SBML is used to capture, store, and distribute computational models by Systems Biology data sources (e.g., the BioModels Database) and researchers. Therefore, there is a need for all-in-one web-based solutions that support advance SBML functionalities such as uploading, editing, composing, visualizing, simulating, querying, and browsing computational models. We present the design and implementation of the Model Composition Tool (Interface) within the PathCase-SB (PathCase Systems Biology) web portal. The tool helps users compose systems biology models to facilitate the complex process of merging systems biology models. We also present three tools that support the model composition tool, namely, (1) Model Simulation Interface that generates a visual plot of the simulation according to user's input, (2) iModel Tool as a platform for users to upload their own models to compose, and (3) SimCom Tool that provides a side by side comparison of models being composed in the same pathway. Finally, we provide a web site that hosts BioModels Database models and a separate web site that hosts SBML Test Suite models. Model composition tool (and the other three tools) can be used with little or no knowledge of the SBML document structure. For this reason, students or anyone who wants to learn about systems biology will benefit from the described functionalities. SBML Test Suite models will be a nice starting point for beginners. And, for more advanced purposes, users will able to access and employ models of the BioModels Database as well.

  8. Online decision support based on modeling with the aim of increased irrigation efficiency

    NASA Astrophysics Data System (ADS)

    Dövényi-Nagy, Tamás; Bakó, Károly; Molnár, Krisztina; Rácz, Csaba; Vasvári, Gyula; Nagy, János; Dobos, Attila

    2015-04-01

    to allow the integration of several public available models and algorithms adapted to local climate (Rácz et al., 2013). The service, the server side framework, scripts and the front-end, providing access to the measured and modeled data, are based on own developments or free available and/or open source softwares and services like Apache, PHP, MySQL and Google Maps API. MetAgro intends to accomplish functionalities of three different areas of usage: research, education and practice. The members differ in educational background, knowledge of models and possibilities to access relevant input data. The system and interfaces must reflect these differences that is accomplished by the degradation of modeling: choosing the place of the farm and the crop already gives some general results, but with every additional parameter given the results are more reliable. The system 'MetAgro' provides a basis for improved decision-making with regard to irrigation on cropland. Based on experiences and feedback, the online application was proved to be useful in the design and practice of reasonable irrigation. In addition to its use in irrigation practice, MetAgro is also a valuable tool for research and education.

  9. Modelling human problem solving with data from an online game.

    PubMed

    Rach, Tim; Kirsch, Alexandra

    2016-11-01

    Since the beginning of cognitive science, researchers have tried to understand human strategies in order to develop efficient and adequate computational methods. In the domain of problem solving, the travelling salesperson problem has been used for the investigation and modelling of human solutions. We propose to extend this effort with an online game, in which instances of the travelling salesperson problem have to be solved in the context of a game experience. We report on our effort to design and run such a game, present the data contained in the resulting openly available data set and provide an outlook on the use of games in general for cognitive science research. In addition, we present three geometrical models mapping the starting point preferences in the problems presented in the game as the result of an evaluation of the data set.

  10. New Model of Teacher Learning in an Online Network

    ERIC Educational Resources Information Center

    Trust, Torrey

    2016-01-01

    While many researchers have examined teacher participation and professional development in online networks and communities, few have looked at the factors and contexts that shape how teachers learn in these online spaces. Examining teachers' learning processes within these online spaces can yield important insights for scholars, school leaders,…

  11. New Model of Teacher Learning in an Online Network

    ERIC Educational Resources Information Center

    Trust, Torrey

    2016-01-01

    While many researchers have examined teacher participation and professional development in online networks and communities, few have looked at the factors and contexts that shape how teachers learn in these online spaces. Examining teachers' learning processes within these online spaces can yield important insights for scholars, school leaders,…

  12. Online-to-offline models in HIV service delivery.

    PubMed

    Anand, Tarandeep; Nitpolprasert, Chattiya; Phanuphak, Nittaya

    2017-09-01

    Half the world's population has access to Internet and technologies, and utilization is near-ubiquitous among providers and key populations. Despite being so well connected; identifying, reaching and linking vulnerable populations to HIV clinical services remains a global challenge. This review highlights the emerging online-to-offline (O2O) models, their potential in scaling up services, and evaluating impact, and implications for future research. Globally, four major types of O2O models have been implemented, primarily in the West and Asia, especially among MSM and transgender women. These models have varying levels of impact in terms of reach, engagement, participation, linkage, and ability to track and monitor participants, and assess outcomes. Those integrated with offline sites enable seamless transition, dramatically reduce the O2O linkage time and demonstrate high linkage success (>73%). O2O models are ideal for at-risk, stigmatized, criminalized populations and for scaling-up biomedical prevention interventions such as preexposure and postexposure prophylaxis. O2O models represent novel and powerful solutions to reverse the pandemic and could help fill significant programmatic gaps in tracking individuals through HIV cascades. Providers, especially in resource-limited settings, could choose between a variety of current approaches highlighted in this review and employ no-cost or cost-effective technologies to transform their traditional models and leverage O2O models.

  13. Continuous Online Sequence Learning with an Unsupervised Neural Network Model.

    PubMed

    Cui, Yuwei; Ahmad, Subutar; Hawkins, Jeff

    2016-09-14

    The ability to recognize and predict temporal sequences of sensory inputs is vital for survival in natural environments. Based on many known properties of cortical neurons, hierarchical temporal memory (HTM) sequence memory recently has been proposed as a theoretical framework for sequence learning in the cortex. In this letter, we analyze properties of HTM sequence memory and apply it to sequence learning and prediction problems with streaming data. We show the model is able to continuously learn a large number of variableorder temporal sequences using an unsupervised Hebbian-like learning rule. The sparse temporal codes formed by the model can robustly handle branching temporal sequences by maintaining multiple predictions until there is sufficient disambiguating evidence. We compare the HTM sequence memory with other sequence learning algorithms, including statistical methods: autoregressive integrated moving average; feedforward neural networks-time delay neural network and online sequential extreme learning machine; and recurrent neural networks-long short-term memory and echo-state networks on sequence prediction problems with both artificial and real-world data. The HTM model achieves comparable accuracy to other state-of-the-art algorithms. The model also exhibits properties that are critical for sequence learning, including continuous online learning, the ability to handle multiple predictions and branching sequences with high-order statistics, robustness to sensor noise and fault tolerance, and good performance without task-specific hyperparameter tuning. Therefore, the HTM sequence memory not only advances our understanding of how the brain may solve the sequence learning problem but is also applicable to real-world sequence learning problems from continuous data streams.

  14. Online coupled regional meteorology chemistry models in Europe: current status and prospects

    NASA Astrophysics Data System (ADS)

    Baklanov, A.; Schlünzen, K.; Suppan, P.; Baldasano, J.; Brunner, D.; Aksoyoglu, S.; Carmichael, G.; Douros, J.; Flemming, J.; Forkel, R.; Galmarini, S.; Gauss, M.; Grell, G.; Hirtl, M.; Joffre, S.; Jorba, O.; Kaas, E.; Kaasik, M.; Kallos, G.; Kong, X.; Korsholm, U.; Kurganskiy, A.; Kushta, J.; Lohmann, U.; Mahura, A.; Manders-Groot, A.; Maurizi, A.; Moussiopoulos, N.; Rao, S. T.; Savage, N.; Seigneur, C.; Sokhi, R. S.; Solazzo, E.; Solomos, S.; Sørensen, B.; Tsegas, G.; Vignati, E.; Vogel, B.; Zhang, Y.

    2014-01-01

    Online coupled mesoscale meteorology atmospheric chemistry models have undergone a rapid evolution in recent years. Although mainly developed by the air quality modelling community, these models are also of interest for numerical weather prediction and regional climate modelling as they can consider not only the effects of meteorology on air quality, but also the potentially important effects of atmospheric composition on weather. Two ways of online coupling can be distinguished: online integrated and online access coupling. Online integrated models simulate meteorology and chemistry over the same grid in one model using one main time step for integration. Online access models use independent meteorology and chemistry modules that might even have different grids, but exchange meteorology and chemistry data on a regular and frequent basis. This article offers a comprehensive review of the current research status of online coupled meteorology and atmospheric chemistry modelling within Europe. Eighteen regional online coupled models developed or being used in Europe are described and compared. Topics discussed include a survey of processes relevant to the interactions between atmospheric physics, dynamics and composition; a brief overview of existing online mesoscale models and European model developments; an analysis on how feedback processes are treated in these models; numerical issues associated with coupled models; and several case studies and model performance evaluation methods. Finally, this article highlights selected scientific issues and emerging challenges that require proper consideration to improve the reliability and usability of these models for the three scientific communities: air quality, numerical meteorology modelling (including weather prediction) and climate modelling. This review will be of particular interest to model developers and users in all three fields as it presents a synthesis of scientific progress and provides recommendations for

  15. Modelling Influence and Opinion Evolution in Online Collective Behaviour

    PubMed Central

    Gend, Pascal; Rentfrow, Peter J.; Hendrickx, Julien M.; Blondel, Vincent D.

    2016-01-01

    Opinion evolution and judgment revision are mediated through social influence. Based on a large crowdsourced in vitro experiment (n = 861), it is shown how a consensus model can be used to predict opinion evolution in online collective behaviour. It is the first time the predictive power of a quantitative model of opinion dynamics is tested against a real dataset. Unlike previous research on the topic, the model was validated on data which did not serve to calibrate it. This avoids to favor more complex models over more simple ones and prevents overfitting. The model is parametrized by the influenceability of each individual, a factor representing to what extent individuals incorporate external judgments. The prediction accuracy depends on prior knowledge on the participants’ past behaviour. Several situations reflecting data availability are compared. When the data is scarce, the data from previous participants is used to predict how a new participant will behave. Judgment revision includes unpredictable variations which limit the potential for prediction. A first measure of unpredictability is proposed. The measure is based on a specific control experiment. More than two thirds of the prediction errors are found to occur due to unpredictability of the human judgment revision process rather than to model imperfection. PMID:27336834

  16. HexServer: an FFT-based protein docking server powered by graphics processors.

    PubMed

    Macindoe, Gary; Mavridis, Lazaros; Venkatraman, Vishwesh; Devignes, Marie-Dominique; Ritchie, David W

    2010-07-01

    HexServer (http://hexserver.loria.fr/) is the first Fourier transform (FFT)-based protein docking server to be powered by graphics processors. Using two graphics processors simultaneously, a typical 6D docking run takes approximately 15 s, which is up to two orders of magnitude faster than conventional FFT-based docking approaches using comparable resolution and scoring functions. The server requires two protein structures in PDB format to be uploaded, and it produces a ranked list of up to 1000 docking predictions. Knowledge of one or both protein binding sites may be used to focus and shorten the calculation when such information is available. The first 20 predictions may be accessed individually, and a single file of all predicted orientations may be downloaded as a compressed multi-model PDB file. The server is publicly available and does not require any registration or identification by the user.

  17. Online Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Meyer Jordan, Bradley, IV; The, Lih-Sin; Robbins, Stuart

    2004-05-01

    Nuclear-reaction network codes are important to astronomers seeking to explore nucleosynthetic implications of astrophysical models and to nuclear physicists seeking to understand the role of nuclear properties or reaction rates in element formation. However, many users do not have the time or inclination to download and compile the codes, to manage the requisite input files, or to explore the often complex output with their own graphics programs. To help make nucleosynthesis calculations more readily available, we have placed the Clemson Nucleosynthesis code on the world-wide web at http://www.ces.clemson.edu/physics/nucleo/nuclearNetwork At this web site, any Internet user may set his or her own reaction network, nuclear properties and reaction rates, and thermodynamic trajectories. The user then submits the nucleosynthesis calculation, which runs on a dedicated server professionally maintained at Clemson University. Once the calculation is completed, the user may explore the results through dynamically produced and downloadable tables and graphs. Online help guides the user through the necessary steps. We hope this web site will prove a user-friendly and helpful tool for professional scientists as well as for students seeking to explore element formation.

  18. TMOC: A Model for Lecturers' Training to Management of Online Courses in Higher-Education

    ERIC Educational Resources Information Center

    Ghilay, Yaron; Ghilay, Ruth

    2014-01-01

    The study examined a new model called TMOC: Training to Management of Online Courses. The model is designed to train lecturers in higher-education to successfully create, deliver and develop online courses. The research was based on a sample of lecturers, who studied in a course based on the new model at the Mofet Institute in Tel-Aviv (n = 20).…

  19. Dynamic Web Pages: Performance Impact on Web Servers.

    ERIC Educational Resources Information Center

    Kothari, Bhupesh; Claypool, Mark

    2001-01-01

    Discussion of Web servers and requests for dynamic pages focuses on experimentally measuring and analyzing the performance of the three dynamic Web page generation technologies: CGI, FastCGI, and Servlets. Develops a multivariate linear regression model and predicts Web server performance under some typical dynamic requests. (Author/LRW)

  20. BUILDING ROBUST APPEARANCE MODELS USING ON-LINE FEATURE SELECTION

    SciTech Connect

    PORTER, REID B.; LOVELAND, ROHAN; ROSTEN, ED

    2007-01-29

    In many tracking applications, adapting the target appearance model over time can improve performance. This approach is most popular in high frame rate video applications where latent variables, related to the objects appearance (e.g., orientation and pose), vary slowly from one frame to the next. In these cases the appearance model and the tracking system are tightly integrated, and latent variables are often included as part of the tracking system's dynamic model. In this paper we describe our efforts to track cars in low frame rate data (1 frame/second) acquired from a highly unstable airborne platform. Due to the low frame rate, and poor image quality, the appearance of a particular vehicle varies greatly from one frame to the next. This leads us to a different problem: how can we build the best appearance model from all instances of a vehicle we have seen so far. The best appearance model should maximize the future performance of the tracking system, and maximize the chances of reacquiring the vehicle once it leaves the field of view. We propose an online feature selection approach to this problem and investigate the performance and computational trade-offs with a real-world dataset.

  1. Enhanced networked server management with random remote backups

    NASA Astrophysics Data System (ADS)

    Kim, Song-Kyoo

    2003-08-01

    In this paper, the model is focused on available server management in network environments. The (remote) backup servers are hooked up by VPN (Virtual Private Network) and replace broken main severs immediately. A virtual private network (VPN) is a way to use a public network infrastructure and hooks up long-distance servers within a single network infrastructure. The servers can be represent as "machines" and then the system deals with main unreliable and random auxiliary spare (remote backup) machines. When the system performs a mandatory routine maintenance, auxiliary machines are being used for backups during idle periods. Unlike other existing models, the availability of auxiliary machines is changed for each activation in this enhanced model. Analytically tractable results are obtained by using several mathematical techniques and the results are demonstrated in the framework of optimized networked server allocation problems.

  2. Dali server update.

    PubMed

    Holm, Liisa; Laakso, Laura M

    2016-07-08

    The Dali server (http://ekhidna2.biocenter.helsinki.fi/dali) is a network service for comparing protein structures in 3D. In favourable cases, comparing 3D structures may reveal biologically interesting similarities that are not detectable by comparing sequences. The Dali server has been running in various places for over 20 years and is used routinely by crystallographers on newly solved structures. The latest update of the server provides enhanced analytics for the study of sequence and structure conservation. The server performs three types of structure comparisons: (i) Protein Data Bank (PDB) search compares one query structure against those in the PDB and returns a list of similar structures; (ii) pairwise comparison compares one query structure against a list of structures specified by the user; and (iii) all against all structure comparison returns a structural similarity matrix, a dendrogram and a multidimensional scaling projection of a set of structures specified by the user. Structural superimpositions are visualized using the Java-free WebGL viewer PV. The structural alignment view is enhanced by sequence similarity searches against Uniprot. The combined structure-sequence alignment information is compressed to a stack of aligned sequence logos. In the stack, each structure is structurally aligned to the query protein and represented by a sequence logo.

  3. Dali server update

    PubMed Central

    Holm, Liisa; Laakso, Laura M.

    2016-01-01

    The Dali server (http://ekhidna2.biocenter.helsinki.fi/dali) is a network service for comparing protein structures in 3D. In favourable cases, comparing 3D structures may reveal biologically interesting similarities that are not detectable by comparing sequences. The Dali server has been running in various places for over 20 years and is used routinely by crystallographers on newly solved structures. The latest update of the server provides enhanced analytics for the study of sequence and structure conservation. The server performs three types of structure comparisons: (i) Protein Data Bank (PDB) search compares one query structure against those in the PDB and returns a list of similar structures; (ii) pairwise comparison compares one query structure against a list of structures specified by the user; and (iii) all against all structure comparison returns a structural similarity matrix, a dendrogram and a multidimensional scaling projection of a set of structures specified by the user. Structural superimpositions are visualized using the Java-free WebGL viewer PV. The structural alignment view is enhanced by sequence similarity searches against Uniprot. The combined structure-sequence alignment information is compressed to a stack of aligned sequence logos. In the stack, each structure is structurally aligned to the query protein and represented by a sequence logo. PMID:27131377

  4. Fully coupled "online" chemistry within the WRF model

    NASA Astrophysics Data System (ADS)

    Grell, Georg A.; Peckham, Steven E.; Schmitz, Rainer; McKeen, Stuart A.; Frost, Gregory; Skamarock, William C.; Eder, Brian

    A fully coupled "online" Weather Research and Forecasting/Chemistry (WRF/Chem) model has been developed. The air quality component of the model is fully consistent with the meteorological component; both components use the same transport scheme (mass and scalar preserving), the same grid (horizontal and vertical components), and the same physics schemes for subgrid-scale transport. The components also use the same timestep, hence no temporal interpolation is needed. The chemistry package consists of dry deposition ("flux-resistance" method), biogenic emission as in [Simpson et al., 1995. Journal of Geophysical Research 100D, 22875-22890; Guenther et al., 1994. Atmospheric Environment 28, 1197-1210], the chemical mechanism from RADM2, a complex photolysis scheme (Madronich scheme coupled with hydrometeors), and a state of the art aerosol module (MADE/SORGAM aerosol parameterization). The WRF/Chem model is statistically evaluated and compared to MM5/Chem and to detailed photochemical data collected during the summer 2002 NEAQS field study. It is shown that the WRF/Chem model is statistically better skilled in forecasting O 3 than MM5/Chem, with no appreciable differences between models in terms of bias with the observations. Furthermore, the WRF/Chem model consistently exhibits better skill at forecasting the O 3 precursors CO and NO y at all of the surface sites. However, the WRF/Chem model biases of these precursors and of other gas-phase species are persistently higher than for MM5/Chem, and are most often biased high compared to observations. Finally, we show that the impact of other basic model assumptions on these same statistics can be much larger than the differences caused by model differences. An example showing the sensitivity of various statistical measures with respect to the treatment of biogenic volatile organic compounds emissions illustrates this impact.

  5. A Design of Product Collaborative Online Configuration Model

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoguo; Zheng, Jin; Zeng, Qian

    According to the actual needs of mass customization, the personalization of product and its collaborative design, the paper analyzes and studies the working mechanism of modular-based product configuration technology and puts forward an information model of modular product family. Combined with case-based reasoning techniques (CBR) and the constraint satisfaction problem solving techniques (CSP), we design and study the algorithm for product configuration, and analyze its time complexity. A car chassis is made as the application object, we provide a prototype system of online configuration. Taking advantage of this system, designers can make appropriate changes on the existing programs in accordance with the demand. This will accelerate all aspects of product development and shorten the product cycle. Also the system will provide a strong technical support for enterprises to improve their market competitiveness.

  6. Fuzzy Modelling for Human Dynamics Based on Online Social Networks

    PubMed Central

    Cuenca-Jara, Jesus; Valdes-Vela, Mercedes; Skarmeta, Antonio F.

    2017-01-01

    Human mobility mining has attracted a lot of attention in the research community due to its multiple implications in the provisioning of innovative services for large metropolises. In this scope, Online Social Networks (OSN) have arisen as a promising source of location data to come up with new mobility models. However, the human nature of this data makes it rather noisy and inaccurate. In order to deal with such limitations, the present work introduces a framework for human mobility mining based on fuzzy logic. Firstly, a fuzzy clustering algorithm extracts the most active OSN areas at different time periods. Next, such clusters are the building blocks to compose mobility patterns. Furthermore, a location prediction service based on a fuzzy rule classifier has been developed on top of the framework. Finally, both the framework and the predictor has been tested with a Twitter and Flickr dataset in two large cities. PMID:28837120

  7. Modelling human mobility patterns using photographic data shared online.

    PubMed

    Barchiesi, Daniele; Preis, Tobias; Bishop, Steven; Moat, Helen Susannah

    2015-08-01

    Humans are inherently mobile creatures. The way we move around our environment has consequences for a wide range of problems, including the design of efficient transportation systems and the planning of urban areas. Here, we gather data about the position in space and time of about 16 000 individuals who uploaded geo-tagged images from locations within the UK to the Flickr photo-sharing website. Inspired by the theory of Lévy flights, which has previously been used to describe the statistical properties of human mobility, we design a machine learning algorithm to infer the probability of finding people in geographical locations and the probability of movement between pairs of locations. Our findings are in general agreement with official figures in the UK and on travel flows between pairs of major cities, suggesting that online data sources may be used to quantify and model large-scale human mobility patterns.

  8. Modelling human mobility patterns using photographic data shared online

    PubMed Central

    Barchiesi, Daniele; Preis, Tobias; Bishop, Steven; Moat, Helen Susannah

    2015-01-01

    Humans are inherently mobile creatures. The way we move around our environment has consequences for a wide range of problems, including the design of efficient transportation systems and the planning of urban areas. Here, we gather data about the position in space and time of about 16 000 individuals who uploaded geo-tagged images from locations within the UK to the Flickr photo-sharing website. Inspired by the theory of Lévy flights, which has previously been used to describe the statistical properties of human mobility, we design a machine learning algorithm to infer the probability of finding people in geographical locations and the probability of movement between pairs of locations. Our findings are in general agreement with official figures in the UK and on travel flows between pairs of major cities, suggesting that online data sources may be used to quantify and model large-scale human mobility patterns. PMID:26361545

  9. GENIUS: web server to predict local gene networks and key genes for biological functions.

    PubMed

    Puelma, Tomas; Araus, Viviana; Canales, Javier; Vidal, Elena A; Cabello, Juan M; Soto, Alvaro; Gutiérrez, Rodrigo A

    2017-03-01

    GENIUS is a user-friendly web server that uses a novel machine learning algorithm to infer functional gene networks focused on specific genes and experimental conditions that are relevant to biological functions of interest. These functions may have different levels of complexity, from specific biological processes to complex traits that involve several interacting processes. GENIUS also enriches the network with new genes related to the biological function of interest, with accuracies comparable to highly discriminative Support Vector Machine methods. GENIUS currently supports eight model organisms and is freely available for public use at http://networks.bio.puc.cl/genius . genius.psbl@gmail.com. Supplementary data are available at Bioinformatics online.

  10. Microsoft SQL Server 6.0{reg_sign} Workbook

    SciTech Connect

    Augustenborg, E.C.

    1996-09-01

    This workbook was prepared for introductory training in the use of Microsoft SQL Server Version 6.0. The examples are all taken from the PUBS database that Microsoft distributes for training purposes or from the Microsoft Online Documentation. The merits of the relational database are presented.

  11. Improvement plans for the RHIC/AGS on-line model environments

    SciTech Connect

    Brown,K.A.; Ahrens, L.; Beebe-Wang, J.; Morris, J.; Nemesure, S.; Robert-Demolaize, G.; Satogata, T.; Schoefer, V.; Tepikian, S.

    2009-08-31

    The on-line models for Relativistic Ion Collider (RHIC) and the RHIC pre-injectors (the AGS and the AGS Booster) can be thought of as containing our best collective knowledge of these accelerators. As we improve these on-line models we are building the framework to have a sophisticated model-based controls system. Currently the RHIC on-line model is an integral part of the controls system, providing the interface for tune control, chromaticity control, and non-linear chromaticity control. What we discuss in this paper is our vision of the future of the on-line model environment for RHIC and the RHIC preinjectors. Although these on-line models are primarily used as Courant-Snyder parameter calculators using live machine settings, we envision expanding these environments to encompass many other problem domains.

  12. SHIR competitive information diffusion model for online social media

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Diao, Su-Meng; Zhu, Yi-Xiang; Liu, Qing

    2016-11-01

    In online social media, opinion divergences and differentiations generally exist as a result of individuals' extensive participation and personalization. In this paper, a Susceptible-Hesitated-Infected-Removed (SHIR) model is proposed to study the dynamics of competitive dual information diffusion. The proposed model extends the classical SIR model by adding hesitators as a neutralized state of dual information competition. It is both hesitators and stable spreaders that facilitate information dissemination. Researching on the impacts of diffusion parameters, it is found that the final density of stiflers increases monotonically as infection rate increases and removal rate decreases. And the advantage information with larger stable transition rate takes control of whole influence of dual information. The density of disadvantage information spreaders slightly grows with the increase of its stable transition rate, while whole spreaders of dual information and the relaxation time remain almost unchanged. Moreover, simulations imply that the final result of competition is closely related to the ratio of stable transition rates of dual information. If the stable transition rates of dual information are nearly the same, a slightly reduction of the smaller one brings out a significant disadvantage in its propagation coverage. Additionally, the relationship of the ratio of final stiflers versus the ratio of stable transition rates presents power characteristic.

  13. Best Practices for Designing Online Learning Environments for 3D Modeling Curricula: A Delphi Study

    ERIC Educational Resources Information Center

    Mapson, Kathleen Harrell

    2011-01-01

    The purpose of this study was to develop an inventory of best practices for designing online learning environments for 3D modeling curricula. Due to the instructional complexity of three-dimensional modeling, few have sought to develop this type of course for online teaching and learning. Considering this, the study aimed to collectively aggregate…

  14. Quasi-Facial Communication for Online Learning Using 3D Modeling Techniques

    ERIC Educational Resources Information Center

    Wang, Yushun; Zhuang, Yueting

    2008-01-01

    Online interaction with 3D facial animation is an alternative way of face-to-face communication for distance education. 3D facial modeling is essential for virtual educational environments establishment. This article presents a novel 3D facial modeling solution that facilitates quasi-facial communication for online learning. Our algorithm builds…

  15. Best Practices for Designing Online Learning Environments for 3D Modeling Curricula: A Delphi Study

    ERIC Educational Resources Information Center

    Mapson, Kathleen Harrell

    2011-01-01

    The purpose of this study was to develop an inventory of best practices for designing online learning environments for 3D modeling curricula. Due to the instructional complexity of three-dimensional modeling, few have sought to develop this type of course for online teaching and learning. Considering this, the study aimed to collectively aggregate…

  16. Introducing the R2D2 Model: Online Learning for the Diverse Learners of This World

    ERIC Educational Resources Information Center

    Bonk, Curtis J.; Zhang, Ke

    2006-01-01

    The R2D2 method--read, reflect, display, and do--is a new model for designing and delivering distance education, and in particular, online learning. Such a model is especially important to address the diverse preferences of online learners of varied generations and varied Internet familiarity. Four quadrants can be utilized separately or as part…

  17. Quasi-Facial Communication for Online Learning Using 3D Modeling Techniques

    ERIC Educational Resources Information Center

    Wang, Yushun; Zhuang, Yueting

    2008-01-01

    Online interaction with 3D facial animation is an alternative way of face-to-face communication for distance education. 3D facial modeling is essential for virtual educational environments establishment. This article presents a novel 3D facial modeling solution that facilitates quasi-facial communication for online learning. Our algorithm builds…

  18. A Maturity Model: Does It Provide a Path for Online Course Design?

    ERIC Educational Resources Information Center

    Neuhauser, Charlotte

    2004-01-01

    Maturity models are successfully used by organizations attempting to improve their processes, products, and delivery. As more faculty include online course design and teaching, a maturity model of online course design may serve as a tool in planning and assessing their courses for improvement based on best practices. This article presents such a…

  19. Logic Models as a Way to Support Online Students and Their Projects

    ERIC Educational Resources Information Center

    Strycker, Jesse

    2016-01-01

    As online enrollment continues to grow, students may need additional pedagogical supports to increase their likelihood of success in online environments that don't offer the same supports as those found in face to face classrooms. Logic models are a way to provide such support to students by helping to model project expectations, allowing students…

  20. Online to offline teaching model in optics education: resource sharing course and flipped class

    NASA Astrophysics Data System (ADS)

    Li, Xiaotong; Cen, Zhaofeng; Liu, Xiangdong; Zheng, Zhenrong

    2016-09-01

    Since the platform "Coursera" is created by the professors of Stanford University Andrew Ng and Daphne Koller, more and more universities have joined in it. From the very beginning, online education is not only about education itself, but also connected with social equality. This is especially significant for the economic transformation in China. In this paper the research and practice on informatization of optical education are described. Online to offline (O2O) education activities, such as online learning and offline meeting, online homework and online to offline discussion, online tests and online to offline evaluation, are combined into our teaching model in the course of Applied Optics. These various O2O strategies were implemented respectively in the autumn-winter small class and the spring-summer middle class according to the constructivism and the idea of open education. We have developed optical education resources such as videos of lectures, light transmission or ray trace animations, online tests, etc. We also divide the learning procedure into 4 steps: First, instead of being given a course offline, students will learn the course online; Second, once a week or two weeks, students will have a discussion in their study groups; Third, students will submit their homework and study reports; Fourth, they will do online and offline tests. The online optical education resources have been shared in some universities in China, together with new challenges to teachers and students when facing the revolution in the e-learning future.

  1. Pathological Buying Online as a Specific Form of Internet Addiction: A Model-Based Experimental Investigation.

    PubMed

    Trotzke, Patrick; Starcke, Katrin; Müller, Astrid; Brand, Matthias

    2015-01-01

    The study aimed to investigate different factors of vulnerability for pathological buying in the online context and to determine whether online pathological buying has parallels to a specific Internet addiction. According to a model of specific Internet addiction by Brand and colleagues, potential vulnerability factors may consist of a predisposing excitability from shopping and as mediating variable, specific Internet use expectancies. Additionally, in line with models on addiction behavior, cue-induced craving should also constitute an important factor for online pathological buying. The theoretical model was tested in this study by investigating 240 female participants with a cue-reactivity paradigm, which was composed of online shopping pictures, to assess excitability from shopping. Craving (before and after the cue-reactivity paradigm) and online shopping expectancies were measured. The tendency for pathological buying and online pathological buying were screened with the Compulsive Buying Scale (CBS) and the Short Internet Addiction Test modified for shopping (s-IATshopping). The results demonstrated that the relationship between individual's excitability from shopping and online pathological buying tendency was partially mediated by specific Internet use expectancies for online shopping (model's R² = .742, p < .001). Furthermore, craving and online pathological buying tendencies were correlated (r = .556, p < .001), and an increase in craving after the cue presentation was observed solely in individuals scoring high for online pathological buying (t(28) = 2.98, p < .01, d = 0.44). Both screening instruments were correlated (r = .517, p < .001), and diagnostic concordances as well as divergences were indicated by applying the proposed cut-off criteria. In line with the model for specific Internet addiction, the study identified potential vulnerability factors for online pathological buying and suggests potential parallels. The presence of craving in

  2. Optimizing Success: A Model for Persistence in Online Education

    ERIC Educational Resources Information Center

    Glazer, Hilda R.; Murphy, John A.

    2015-01-01

    The first-year experience for students enrolled in an online degree program, particularly the orientation and the first course experience, is critical to success and completion. The experience of one online university in improving persistence through enhancing orientation and the first academic course is presented. Factors impacting persistence…

  3. Modeling Best Practice through Online Learning: Building Relationships

    ERIC Educational Resources Information Center

    Cerniglia, Ellen G.

    2011-01-01

    Students may fear that they will feel unsupported and isolated when engaged in online learning. They don't know how they will be able to build relationships with their teacher and classmates solely based on written words, without facial expressions, tone of voice, and other nonverbal communication cues. Traditionally, online learning required…

  4. A Maturity Model for Online Classes across Academic Disciplines

    ERIC Educational Resources Information Center

    Neequaye, Barbara Burris

    2013-01-01

    The number of academic institutions offering courses online has increased with courses being offered across almost all academic disciplines. Faculty members are often confronted with the responsibility of converting a face-to-face course to an online course while simultaneously dealing with new technologies and the interrelationship between the…

  5. A Structural Equation Model of Predictors of Online Learning Retention

    ERIC Educational Resources Information Center

    Lee, Youngju; Choi, Jaeho

    2013-01-01

    This study examined the effects of internal academic locus of control (ALOC), learning strategies, flow experience, and student satisfaction on student retention in online learning courses. A total number of 282 adult students at the Korea National Open University participated in the study by completing an online survey adopted from previous…

  6. A Maturity Model for Online Classes across Academic Disciplines

    ERIC Educational Resources Information Center

    Neequaye, Barbara Burris

    2013-01-01

    The number of academic institutions offering courses online has increased with courses being offered across almost all academic disciplines. Faculty members are often confronted with the responsibility of converting a face-to-face course to an online course while simultaneously dealing with new technologies and the interrelationship between the…

  7. A Structural Equation Model of Predictors of Online Learning Retention

    ERIC Educational Resources Information Center

    Lee, Youngju; Choi, Jaeho

    2013-01-01

    This study examined the effects of internal academic locus of control (ALOC), learning strategies, flow experience, and student satisfaction on student retention in online learning courses. A total number of 282 adult students at the Korea National Open University participated in the study by completing an online survey adopted from previous…

  8. Effective Live Online Faculty Development Workshops: One Model

    ERIC Educational Resources Information Center

    Blyth, Russell D.; May, Michael K.; Rainbolt, Julianne G.

    2006-01-01

    This article describes live, online faculty development workshops that show faculty how to use software packages (to date, GAP and Maple) in teaching college-level mathematics. The authors' primary goal in this article is to encourage others in any discipline to run similar online workshops by providing a resource for their successful operation,…

  9. Personal Health: An Online Model for Health Education.

    ERIC Educational Resources Information Center

    Hohman, Stephen

    2003-01-01

    Ohio University's Community Health Program has developed a unique online personal health course that combines online learning and classroom participation to support student success. It has improved the consistency of information presented to students and increased overall quality. Guidelines are presented for preparing and implementing such…

  10. Modeling Best Practice through Online Learning: Building Relationships

    ERIC Educational Resources Information Center

    Cerniglia, Ellen G.

    2011-01-01

    Students may fear that they will feel unsupported and isolated when engaged in online learning. They don't know how they will be able to build relationships with their teacher and classmates solely based on written words, without facial expressions, tone of voice, and other nonverbal communication cues. Traditionally, online learning required…

  11. Learning online community citizenship behavior: a socio-cognitive model.

    PubMed

    Joe, Sheng-Wuu; Lin, Chieh-Peng

    2008-06-01

    This study postulates personal and environmental factors as key drivers of online community citizenship behavior (OCCB). OCCB reveals that the individual chooses to perform a behavior that is beneficial to others. Empirical results confirm the applicability of social cognitive theory (SCT) in online communities.

  12. Optimizing Success: A Model for Persistence in Online Education

    ERIC Educational Resources Information Center

    Glazer, Hilda R.; Murphy, John A.

    2015-01-01

    The first-year experience for students enrolled in an online degree program, particularly the orientation and the first course experience, is critical to success and completion. The experience of one online university in improving persistence through enhancing orientation and the first academic course is presented. Factors impacting persistence…

  13. A novel information cascade model in online social networks

    NASA Astrophysics Data System (ADS)

    Tong, Chao; He, Wenbo; Niu, Jianwei; Xie, Zhongyu

    2016-02-01

    The spread and diffusion of information has become one of the hot issues in today's social network analysis. To analyze the spread of online social network information and the attribute of cascade, in this paper, we discuss the spread of two kinds of users' decisions for city-wide activities, namely the "want to take part in the activity" and "be interested in the activity", based on the users' attention in "DouBan" and the data of the city-wide activities. We analyze the characteristics of the activity-decision's spread in these aspects: the scale and scope of the cascade subgraph, the structure characteristic of the cascade subgraph, the topological attribute of spread tree, and the occurrence frequency of cascade subgraph. On this basis, we propose a new information spread model. Based on the classical independent diffusion model, we introduce three mechanisms, equal probability, similarity of nodes, and popularity of nodes, which can generate and affect the spread of information. Besides, by conducting the experiments in six different kinds of network data set, we compare the effects of three mechanisms above mentioned, totally six specific factors, on the spread of information, and put forward that the node's popularity plays an important role in the information spread.

  14. Pathological Buying Online as a Specific Form of Internet Addiction: A Model-Based Experimental Investigation

    PubMed Central

    Trotzke, Patrick; Starcke, Katrin; Müller, Astrid; Brand, Matthias

    2015-01-01

    The study aimed to investigate different factors of vulnerability for pathological buying in the online context and to determine whether online pathological buying has parallels to a specific Internet addiction. According to a model of specific Internet addiction by Brand and colleagues, potential vulnerability factors may consist of a predisposing excitability from shopping and as mediating variable, specific Internet use expectancies. Additionally, in line with models on addiction behavior, cue-induced craving should also constitute an important factor for online pathological buying. The theoretical model was tested in this study by investigating 240 female participants with a cue-reactivity paradigm, which was composed of online shopping pictures, to assess excitability from shopping. Craving (before and after the cue-reactivity paradigm) and online shopping expectancies were measured. The tendency for pathological buying and online pathological buying were screened with the Compulsive Buying Scale (CBS) and the Short Internet Addiction Test modified for shopping (s-IATshopping). The results demonstrated that the relationship between individual’s excitability from shopping and online pathological buying tendency was partially mediated by specific Internet use expectancies for online shopping (model’s R² = .742, p < .001). Furthermore, craving and online pathological buying tendencies were correlated (r = .556, p < .001), and an increase in craving after the cue presentation was observed solely in individuals scoring high for online pathological buying (t(28) = 2.98, p < .01, d = 0.44). Both screening instruments were correlated (r = .517, p < .001), and diagnostic concordances as well as divergences were indicated by applying the proposed cut-off criteria. In line with the model for specific Internet addiction, the study identified potential vulnerability factors for online pathological buying and suggests potential parallels. The presence of craving in

  15. WebRASP: a server for computing energy scores to assess the accuracy and stability of RNA 3D structures

    PubMed Central

    Norambuena, Tomas; Cares, Jorge F.; Capriotti, Emidio; Melo, Francisco

    2013-01-01

    Summary: The understanding of the biological role of RNA molecules has changed. Although it is widely accepted that RNAs play important regulatory roles without necessarily coding for proteins, the functions of many of these non-coding RNAs are unknown. Thus, determining or modeling the 3D structure of RNA molecules as well as assessing their accuracy and stability has become of great importance for characterizing their functional activity. Here, we introduce a new web application, WebRASP, that uses knowledge-based potentials for scoring RNA structures based on distance-dependent pairwise atomic interactions. This web server allows the users to upload a structure in PDB format, select several options to visualize the structure and calculate the energy profile. The server contains online help, tutorials and links to other related resources. We believe this server will be a useful tool for predicting and assessing the quality of RNA 3D structures. Availability and implementation: The web server is available at http://melolab.org/webrasp. It has been tested on the most popular web browsers and requires Java plugin for Jmol visualization. Contact: fmelo@bio.puc.cl PMID:23929030

  16. Suicide prevention by online support groups: an action theory-based model of emotional first aid.

    PubMed

    Gilat, Itzhak; Shahar, Golan

    2009-01-01

    In the last two decades, online support groups have become a valuable source of help for individuals in suicidal crisis. Their attractiveness is attributed to features that enhance help-seeking and self-disclosure such as availability, anonymity, and use of written communication. However, online support groups also suffer from limitations and potential risks as agents of suicide prevention. The Israeli Association for Emotional First Aid (ERAN) has developed a practical model that seeks to maximize the benefits and minimize the risks of online suicide prevention. The model applies the Action Theory concepts whereby individuals shape their own environment. The present paper presents the model, which is based on an online support group combined with personal chat and a telephonic help line. The online support group is moderated by paraprofessionals who function as both process regulators and support providers. The principles and practice of the model are described, the theoretical rationale is presented, and directions for future research are suggested.

  17. PDS: A Performance Database Server

    DOE PAGES

    Berry, Michael W.; Dongarra, Jack J.; Larose, Brian H.; ...

    1994-01-01

    The process of gathering, archiving, and distributing computer benchmark data is a cumbersome task usually performed by computer users and vendors with little coordination. Most important, there is no publicly available central depository of performance data for all ranges of machines from personal computers to supercomputers. We present an Internet-accessible performance database server (PDS) that can be used to extract current benchmark data and literature. As an extension to the X-Windows-based user interface (Xnetlib) to the Netlib archival system, PDS provides an on-line catalog of public domain computer benchmarks such as the LINPACK benchmark, Perfect benchmarks, and the NAS parallelmore » benchmarks. PDS does not reformat or present the benchmark data in any way that conflicts with the original methodology of any particular benchmark; it is thereby devoid of any subjective interpretations of machine performance. We believe that all branches (research laboratories, academia, and industry) of the general computing community can use this facility to archive performance metrics and make them readily available to the public. PDS can provide a more manageable approach to the development and support of a large dynamic database of published performance metrics.« less

  18. Structural Equation Modeling towards Online Learning Readiness, Academic Motivations, and Perceived Learning

    ERIC Educational Resources Information Center

    Horzum, Mehmet Baris; Kaymak, Zeliha Demir; Gungoren, Ozlem Canan

    2015-01-01

    The relationship between online learning readiness, academic motivations, and perceived learning was investigated via structural equation modeling in the research. The population of the research consisted of 750 students who studied using the online learning programs of Sakarya University. 420 of the students who volunteered for the research and…

  19. Online Synchronous vs. Asynchronous Software Training through the Behavioral Modeling Approach: A Longitudinal Field Experiment

    ERIC Educational Resources Information Center

    Chen, Charlie C.; Shaw, Ruey-shiang

    2006-01-01

    The continued and increasing use of online training raises the question of whether the most effective training methods applied in live instruction will carry over to different online environments in the long run. Behavior Modeling (BM) approach--teaching through demonstration--has been proven as the most effective approach in a face-to-face (F2F)…

  20. Using the Cognitive Apprenticeship Model with a Chat Tool to Enhance Online Collaborative Learning

    ERIC Educational Resources Information Center

    Rodríguez-Bonces, Mónica; Ortiz, Kris

    2016-01-01

    In Colombia, many institutions are in the firm quest of virtual learning environments to improve instruction, and making the most of online tools is clearly linked to offering quality learning. Thus, the purpose of this action research was to identify how the Cognitive Apprenticeship Model enhances online collaborative learning by using a chat…

  1. Students' Performance at Tutorial Online of Social Studies through the Use of Learning Cycle Model

    ERIC Educational Resources Information Center

    Farisi, Mohammad Imam

    2014-01-01

    The purpose of the study is to describe student's performance in tutorial online (tuton) of Social Studies through developing the 5Es--Engage Explore, Explain, Elaborate, and Evaluate--Learning Cycle Model (the 5Es-LCM). The study conducted at UT-Online portal uses the Research and Development (R&D) method. The research subjects consisted of…

  2. Open Online Language Courses: The Multi-Level Model of the Spanish N(ottingham)OOC

    ERIC Educational Resources Information Center

    Goria, Cecilia; Lagares, Manuel

    2015-01-01

    Research into open education has identified a "high number of participants" and "unpredictable mixed abilities" as factors responsible for the relatively weak presence of language Massive Open Online Courses (MOOCs). This contribution presents a model for open online language courses that aims to bridge this gap. The tangible…

  3. The Radical Model--A Painless Way To Teach On-Line.

    ERIC Educational Resources Information Center

    Romm, C.; Taylor, W.

    The information technology/information systems (IT/IS) education sector needs to come up with creative ways of thinking about on-line education. In this paper, the major themes in the literature on on-line education to date are highlighted with a view to identifying issues that are either missing or under-emphasized. Next, the "radical model of…

  4. New Learning Models: The Evolution of Online Learning into Innovative K-12 Blended Programs

    ERIC Educational Resources Information Center

    Patrick, Susan

    2011-01-01

    The author traces the growth of K-12 online learning in the United States from its modest genesis in the mid-1990s with 50,000 students to the more than 4 million enrollments today, the fastest scaling ever of any innovation in K-12 education. The evolution from one-size-fits-all online courses to innovative, blended instructional models that are…

  5. Online Synchronous vs. Asynchronous Software Training through the Behavioral Modeling Approach: A Longitudinal Field Experiment

    ERIC Educational Resources Information Center

    Chen, Charlie C.; Shaw, Ruey-shiang

    2006-01-01

    The continued and increasing use of online training raises the question of whether the most effective training methods applied in live instruction will carry over to different online environments in the long run. Behavior Modeling (BM) approach--teaching through demonstration--has been proven as the most effective approach in a face-to-face (F2F)…

  6. Online Teaching in K-12: Models, Methods, and Best Practices for Teachers and Administrators

    ERIC Educational Resources Information Center

    Bryans-Bongey, Sarah, Ed.; Graziano, Kevin J., Ed.

    2016-01-01

    "Online Teaching in K-12" is the essential hands-on reference and textbook for education professionals seeking success in the planning, design, and teaching of K-12 online courses and programs. This skillfully edited book brings together more than two dozen experts and practitioners to present an array of innovative models and methods,…

  7. Talking about Reading as Thinking: Modeling the Hidden Complexities of Online Reading Comprehension

    ERIC Educational Resources Information Center

    Coiro, Julie

    2011-01-01

    This article highlights four cognitive processes key to online reading comprehension and how one might begin to transform existing think-aloud strategy models to encompass the challenges of reading for information on the Internet. Informed by principles of cognitive apprenticeship and an emerging taxonomy of online reading comprehension…

  8. 78 FR 48472 - Hewlett Packard Company; Enterprise Storage Servers and Networking (Tape) Group; Formerly D/B/A...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Hewlett Packard Company; Enterprise Storage Servers and Networking..., Enterprise Storage Servers and Networking (Tape) Group (formerly d/b/a Enterprise Group, HP Storage,...

  9. Exploring key factors in online shopping with a hybrid model.

    PubMed

    Chen, Hsiao-Ming; Wu, Chia-Huei; Tsai, Sang-Bing; Yu, Jian; Wang, Jiangtao; Zheng, Yuxiang

    2016-01-01

    Nowadays, the web increasingly influences retail sales. An in-depth analysis of consumer decision-making in the context of e-business has become an important issue for internet vendors. However, factors affecting e-business are complicated and intertwined. To stimulate online sales, understanding key influential factors and causal relationships among the factors is important. To gain more insights into this issue, this paper introduces a hybrid method, which combines the Decision Making Trial and Evaluation Laboratory (DEMATEL) with the analytic network process, called DANP method, to find out the driving factors that influence the online business mostly. By DEMATEL approach the causal graph showed that "online service" dimension has the highest degree of direct impact on other dimensions; thus, the internet vendor is suggested to made strong efforts on service quality throughout the online shopping process. In addition, the study adopted DANP to measure the importance of key factors, among which "transaction security" proves to be the most important criterion. Hence, transaction security should be treated with top priority to boost the online businesses. From our study with DANP approach, the comprehensive information can be visually detected so that the decision makers can spotlight on the root causes to develop effectual actions.

  10. Implementing Adaptive Performance Management in Server Applications

    SciTech Connect

    Liu, Yan; Gorton, Ian

    2007-06-11

    Performance and scalability are critical quality attributes for server applications in Internet-facing business systems. These applications operate in dynamic environments with rapidly fluctuating user loads and resource levels, and unpredictable system faults. Adaptive (autonomic) systems research aims to augment such server applications with intelligent control logic that can detect and react to sudden environmental changes. However, developing this adaptive logic is complex in itself. In addition, executing the adaptive logic consumes processing resources, and hence may (paradoxically) adversely affect application performance. In this paper we describe an approach for developing high-performance adaptive server applications and the supporting technology. The Adaptive Server Framework (ASF) is built on standard middleware services, and can be used to augment legacy systems with adaptive behavior without needing to change the application business logic. Crucially, ASF provides built-in control loop components to optimize the overall application performance, which comprises both the business and adaptive logic. The control loop is based on performance models and allows systems designers to tune the performance levels simply by modifying high level declarative policies. We demonstrate the use of ASF in a case study.

  11. Intelligence Data Object Server (IDOS)

    NASA Astrophysics Data System (ADS)

    Barnum, Doug J.; Barth, Stephen W.

    2002-07-01

    The Intelligence Data Object Server (IDOS) has been developed under the Air Force Research Laboratory Global Information Base Branch (AFRL/IFED) Global Awareness Virtual Testbed project to provide automated mechanisms for using Military Intelligence Data in modeling and simulation experiments. The IDOS software allows information from multiple data sources to be published in exercises using the High Level Architecture (HLA) or other object-oriented formats. IDOS uses the AFRL/IFEB Broadsword Gatekeeper for data source access. IDOS has been used in simulation-based acquisition experiments designed and carried out among distributed AFRL sites. This paper describes the IDOS architecture and capabilities including the use of the eXtensible Markup Language (XML) to provide a common representation for data objects, and application of IDOS to visualization of Intelligence Information.

  12. NEOS server 4.0 administrative guide.

    SciTech Connect

    Dolan, E. D.

    2001-07-13

    The NEOS Server 4.0 provides a general Internet-based client/server as a link between users and software applications. The administrative guide covers the fundamental principals behind the operation of the NEOS Server, installation and trouble-shooting of the Server software, and implementation details of potential interest to a NEOS Server administrator. The guide also discusses making new software applications available through the Server, including areas of concern to remote solver administrators such as maintaining security, providing usage instructions, and enforcing reasonable restrictions on jobs. The administrative guide is intended both as an introduction to the NEOS Server and as a reference for use when running the Server.

  13. PACS image security server

    NASA Astrophysics Data System (ADS)

    Cao, Fei; Huang, H. K.

    2004-04-01

    Medical image security in a PACS environment has become a pressing issue as communications of images increasingly extends over open networks, and hospitals are currently hard-pushed by Health Insurance Portability and Accountability Act (HIPAA) to be HIPPA complaint for ensuring health data security. Other security-related guidelines and technical standards continue bringing to the public attention in healthcare. However, there is not an infrastructure or systematic method to implement and deploy these standards in a PACS. In this paper, we first review DICOM Part15 standard for secure communications of medical images and the HIPAA impacts on PACS security, as well as our previous works on image security. Then we outline a security infrastructure in a HIPAA mandated PACS environment using a dedicated PACS image security server. The server manages its own database of all image security information. It acts as an image Authority for checking and certificating the image origin and integrity upon request by a user, as a secure DICOM gateway to the outside connections and meanwhile also as a PACS operation monitor for HIPAA supporting information.

  14. Programmatic, Systematic, Automatic: An Online Course Accessibility Support Model

    ERIC Educational Resources Information Center

    Bastedo, Kathleen; Sugar, Amy; Swenson, Nancy; Vargas, Jessica

    2013-01-01

    Over the past few years, there has been a noticeable increase in the number of requests for online course material accommodations at the University of Central Florida (UCF). In response to these requests, UCF's Center for Distributed Learning (CDL) formed new teams, reevaluated its processes, and initiated a partnership with UCF's Student…

  15. Free Textbooks: An Online Company Tries a Controversial Publishing Model

    ERIC Educational Resources Information Center

    Rampell, Catherine

    2008-01-01

    The high prices of textbooks, which are approaching $1,000 per year for an average student, have those students and their professors crying for mercy. Flat World Knowledge, a new digital-textbook publisher, has the answer to this problem. Starting next year, the publisher will offer online, peer-reviewed, interactive, user-editable textbooks, free…

  16. Enhanced Online Access Requires Redesigned Delivery Options and Cost Models

    ERIC Educational Resources Information Center

    Stern, David

    2007-01-01

    Rapidly developing online information technologies provide dramatically new capabilities and opportunities, and place new responsibilities on all involved to recreate networks for scholarly communication. Collaborations between all segments of the information network are made possible and necessary as we attempt to find a balanced and mutually…

  17. Managing Staff Development for Online Education: A Situated Learning Model.

    ERIC Educational Resources Information Center

    Taylor, Janet A.

    2003-01-01

    Describes the implementation and management of staff development for online education underpinned by the principles of situated learning. Describes technological, human resource, pedagogical, and management initiatives and presents a case study of how a small regional institution changed to being an internationally recognized e-university. (EV)

  18. A Model for Social Presence in Online Classrooms

    ERIC Educational Resources Information Center

    Wei, Chun-Wang; Chen, Nian-Shing; Kinshuk,

    2012-01-01

    It is now possible to create flexible learning environments without time and distance barriers on the internet. However, research has shown that learners typically experience isolation and alienation in online learning environments. These negative experiences can be reduced by enhancing social presence. In order to better facilitate the perceived…

  19. A Model for Social Presence in Online Classrooms

    ERIC Educational Resources Information Center

    Wei, Chun-Wang; Chen, Nian-Shing; Kinshuk,

    2012-01-01

    It is now possible to create flexible learning environments without time and distance barriers on the internet. However, research has shown that learners typically experience isolation and alienation in online learning environments. These negative experiences can be reduced by enhancing social presence. In order to better facilitate the perceived…

  20. Free Textbooks: An Online Company Tries a Controversial Publishing Model

    ERIC Educational Resources Information Center

    Rampell, Catherine

    2008-01-01

    The high prices of textbooks, which are approaching $1,000 per year for an average student, have those students and their professors crying for mercy. Flat World Knowledge, a new digital-textbook publisher, has the answer to this problem. Starting next year, the publisher will offer online, peer-reviewed, interactive, user-editable textbooks, free…

  1. Designing Online Workshops: Using an Experiential Learning Model

    ERIC Educational Resources Information Center

    Lynch, Sherry K.; Kogan, Lori R.

    2004-01-01

    This article describes 4 online workshops designed to assist college students with improving their time management, textbook reading, memory and concentration, and overall academic performance. These workshops were created to work equally well with imaginative, analytic, common-sense, and dynamic learners. Positive student feedback indicated that…

  2. Trayectorias: A New Model for Online Task-Based Learning

    ERIC Educational Resources Information Center

    Ros i Sole, Cristina; Mardomingo, Raquel

    2004-01-01

    This paper discusses a framework for designing online tasks that capitalizes on the possibilities that the Internet and the Web offer for language learning. To present such a framework, we draw from constructivist theories (Brooks and Brooks, 1993) and their application to educational technology (Newby, Stepich, Lehman and Russell, 1996; Jonassen,…

  3. Developing Online/Hybrid Learning Models for Higher Education Programs

    ERIC Educational Resources Information Center

    Young, William; Allen, Linda; Warfield, Kimberly

    2016-01-01

    Colleges and universities are looking for creative ways to increase student enrollment while providing flexible course offerings and maintaining adequate fiscal stewardship. This review of selected literature advocates for the use of online instruction in higher education in order to address, with instructional fidelity, the learning preferences…

  4. An Inclusive Approach to Online Learning Environments: Models and Resources

    ERIC Educational Resources Information Center

    Rutherford, Aline Germain; Kerr, Barbara

    2008-01-01

    The impact of ever-increasing numbers of online courses on the demographic composition of classes has meant that the notions of diversity, multiculturality and globalization are now key aspects of curriculum planning. With the internationalization and globalization of education, and faced with rising needs for an increasingly educated and more…

  5. Statistical Discourse Analysis: A Method for Modelling Online Discussion Processes

    ERIC Educational Resources Information Center

    Chiu, Ming Ming; Fujita, Nobuko

    2014-01-01

    Online forums (synchronous and asynchronous) offer exciting data opportunities to analyze how people influence one another through their interactions. However, researchers must address several analytic difficulties involving the data (missing values, nested structure [messages within topics], non-sequential messages), outcome variables (discrete…

  6. Experimental parametric study of servers cooling management in data centers buildings

    NASA Astrophysics Data System (ADS)

    Nada, S. A.; Elfeky, K. E.; Attia, Ali M. A.; Alshaer, W. G.

    2017-01-01

    A parametric study of air flow and cooling management of data centers servers is experimentally conducted for different design conditions. A physical scale model of data center accommodating one rack of four servers was designed and constructed for testing purposes. Front and rear rack and server's temperatures distributions and supply/return heat indices (SHI/RHI) are used to evaluate data center thermal performance. Experiments were conducted to parametrically study the effects of perforated tiles opening ratio, servers power load variation and rack power density. The results showed that (1) perforated tile of 25% opening ratio provides the best results among the other opening ratios, (2) optimum benefit of cold air in servers cooling is obtained at uniformly power loading of servers (3) increasing power density decrease air re-circulation but increase air bypass and servers temperature. The present results are compared with previous experimental and CFD results and fair agreement was found.

  7. Experimental parametric study of servers cooling management in data centers buildings

    NASA Astrophysics Data System (ADS)

    Nada, S. A.; Elfeky, K. E.; Attia, Ali M. A.; Alshaer, W. G.

    2017-06-01

    A parametric study of air flow and cooling management of data centers servers is experimentally conducted for different design conditions. A physical scale model of data center accommodating one rack of four servers was designed and constructed for testing purposes. Front and rear rack and server's temperatures distributions and supply/return heat indices (SHI/RHI) are used to evaluate data center thermal performance. Experiments were conducted to parametrically study the effects of perforated tiles opening ratio, servers power load variation and rack power density. The results showed that (1) perforated tile of 25% opening ratio provides the best results among the other opening ratios, (2) optimum benefit of cold air in servers cooling is obtained at uniformly power loading of servers (3) increasing power density decrease air re-circulation but increase air bypass and servers temperature. The present results are compared with previous experimental and CFD results and fair agreement was found.

  8. ArachnoServer: a database of protein toxins from spiders

    PubMed Central

    2009-01-01

    Background Venomous animals incapacitate their prey using complex venoms that can contain hundreds of unique protein toxins. The realisation that many of these toxins may have pharmaceutical and insecticidal potential due to their remarkable potency and selectivity against target receptors has led to an explosion in the number of new toxins being discovered and characterised. From an evolutionary perspective, spiders are the most successful venomous animals and they maintain by far the largest pool of toxic peptides. However, at present, there are no databases dedicated to spider toxins and hence it is difficult to realise their full potential as drugs, insecticides, and pharmacological probes. Description We have developed ArachnoServer, a manually curated database that provides detailed information about proteinaceous toxins from spiders. Key features of ArachnoServer include a new molecular target ontology designed especially for venom toxins, the most up-to-date taxonomic information available, and a powerful advanced search interface. Toxin information can be browsed through dynamic trees, and each toxin has a dedicated page summarising all available information about its sequence, structure, and biological activity. ArachnoServer currently manages 567 protein sequences, 334 nucleic acid sequences, and 51 protein structures. Conclusion ArachnoServer provides a single source of high-quality information about proteinaceous spider toxins that will be an invaluable resource for pharmacologists, neuroscientists, toxinologists, medicinal chemists, ion channel scientists, clinicians, and structural biologists. ArachnoServer is available online at http://www.arachnoserver.org. PMID:19674480

  9. Remote Sensing Data Analytics for Planetary Science with PlanetServer/EarthServer

    NASA Astrophysics Data System (ADS)

    Rossi, Angelo Pio; Figuera, Ramiro Marco; Flahaut, Jessica; Martinot, Melissa; Misev, Dimitar; Baumann, Peter; Pham Huu, Bang; Besse, Sebastien

    2016-04-01

    Planetary Science datasets, beyond the change in the last two decades from physical volumes to internet-accessible archives, still face the problem of large-scale processing and analytics (e.g. Rossi et al., 2014, Gaddis and Hare, 2015). PlanetServer, the Planetary Science Data Service of the EC-funded EarthServer-2 project (#654367) tackles the planetary Big Data analytics problem with an array database approach (Baumann et al., 2014). It is developed to serve a large amount of calibrated, map-projected planetary data online, mainly through Open Geospatial Consortium (OGC) Web Coverage Processing Service (WCPS) (e.g. Rossi et al., 2014; Oosthoek et al., 2013; Cantini et al., 2014). The focus of the H2020 evolution of PlanetServer is still on complex multidimensional data, particularly hyperspectral imaging and topographic cubes and imagery. In addition to hyperspectral and topographic from Mars (Rossi et al., 2014), the use of WCPS is applied to diverse datasets on the Moon, as well as Mercury. Other Solar System Bodies are going to be progressively available. Derived parameters such as summary products and indices can be produced through WCPS queries, as well as derived imagery colour combination products, dynamically generated and accessed also through OGC Web Coverage Service (WCS). Scientific questions translated into queries can be posed to a large number of individual coverages (data products), locally, regionally or globally. The new PlanetServer system uses the the Open Source Nasa WorldWind (e.g. Hogan, 2011) virtual globe as visualisation engine, and the array database Rasdaman Community Edition as core server component. Analytical tools and client components of relevance for multiple communities and disciplines are shared across service such as the Earth Observation and Marine Data Services of EarthServer. The Planetary Science Data Service of EarthServer is accessible on http://planetserver.eu. All its code base is going to be available on GitHub, on

  10. NCI's Distributed Geospatial Data Server

    NASA Astrophysics Data System (ADS)

    Larraondo, P. R.; Evans, B. J. K.; Antony, J.

    2016-12-01

    Earth systems, environmental and geophysics datasets are an extremely valuable source of information about the state and evolution of the Earth. However, different disciplines and applications require this data to be post-processed in different ways before it can be used. For researchers experimenting with algorithms across large datasets or combining multiple data sets, the traditional approach to batch data processing and storing all the output for later analysis rapidly becomes unfeasible, and often requires additional work to publish for others to use. Recent developments on distributed computing using interactive access to significant cloud infrastructure opens the door for new ways of processing data on demand, hence alleviating the need for storage space for each individual copy of each product. The Australian National Computational Infrastructure (NCI) has developed a highly distributed geospatial data server which supports interactive processing of large geospatial data products, including satellite Earth Observation data and global model data, using flexible user-defined functions. This system dynamically and efficiently distributes the required computations among cloud nodes and thus provides a scalable analysis capability. In many cases this completely alleviates the need to preprocess and store the data as products. This system presents a standards-compliant interface, allowing ready accessibility for users of the data. Typical data wrangling problems such as handling different file formats and data types, or harmonising the coordinate projections or temporal and spatial resolutions, can now be handled automatically by this service. The geospatial data server exposes functionality for specifying how the data should be aggregated and transformed. The resulting products can be served using several standards such as the Open Geospatial Consortium's (OGC) Web Map Service (WMS) or Web Feature Service (WFS), Open Street Map tiles, or raw binary arrays under

  11. The Effects of Presentation Format for Behavior Modeling of Interpersonal Skills in Online Instruction

    ERIC Educational Resources Information Center

    Doo, Min Young

    2005-01-01

    The purpose of this study was to identify the most effective model presentation format in behavior modeling to teach interpersonal skills in online learning environments. Four model presentation formats were compared; video, pictures plus audio, audio only, and text-script only. The effects of the model presentation were investigated in terms of…

  12. Addressing Diverse Learner Preferences and Intelligences with Emerging Technologies: Matching Models to Online Opportunities

    ERIC Educational Resources Information Center

    Zhang, Ke; Bonk, Curtis J.

    2008-01-01

    This paper critically reviews various learning preferences and human intelligence theories and models with a particular focus on the implications for online learning. It highlights a few key models, Gardner's multiple intelligences, Fleming and Mills' VARK model, Honey and Mumford's Learning Styles, and Kolb's Experiential Learning Model, and…

  13. Client/server approach to image capturing

    NASA Astrophysics Data System (ADS)

    Tuijn, Chris; Stokes, Earle

    1998-01-01

    The diversity of the digital image capturing devices on the market today is quite astonishing and ranges from low-cost CCD scanners to digital cameras (for both action and stand-still scenes), mid-end CCD scanners for desktop publishing and pre- press applications and high-end CCD flatbed scanners and drum- scanners with photo multiplier technology. Each device and market segment has its own specific needs which explains the diversity of the associated scanner applications. What all those applications have in common is the need to communicate with a particular device to import the digital images; after the import, additional image processing might be needed as well as color management operations. Although the specific requirements for all of these applications might differ considerably, a number of image capturing and color management facilities as well as other services are needed which can be shared. In this paper, we propose a client/server architecture for scanning and image editing applications which can be used as a common component for all these applications. One of the principal components of the scan server is the input capturing module. The specification of the input jobs is based on a generic input device model. Through this model we make abstraction of the specific scanner parameters and define the scan job definitions by a number of absolute parameters. As a result, scan job definitions will be less dependent on a particular scanner and have a more universal meaning. In this context, we also elaborate on the interaction of the generic parameters and the color characterization (i.e., the ICC profile). Other topics that are covered are the scheduling and parallel processing capabilities of the server, the image processing facilities, the interaction with the ICC engine, the communication facilities (both in-memory and over the network) and the different client architectures (stand-alone applications, TWAIN servers, plug-ins, OLE or Apple-event driven

  14. Client - server programs analysis in the EPOCA environment

    NASA Astrophysics Data System (ADS)

    Donatelli, Susanna; Mazzocca, Nicola; Russo, Stefano

    1996-09-01

    Client - server processing is a popular paradigm for distributed computing. In the development of client - server programs, the designer has first to ensure that the implementation behaves correctly, in particular that it is deadlock free. Second, he has to guarantee that the program meets predefined performance requirements. This paper addresses the issues in the analysis of client - server programs in EPOCA. EPOCA is a computer-aided software engeneering (CASE) support system that allows the automated construction and analysis of generalized stochastic Petri net (GSPN) models of concurrent applications. The paper describes, on the basis of a realistic case study, how client - server systems are modelled in EPOCA, and the kind of qualitative and quantitative analysis supported by its tools.

  15. Purge Lock Server

    SciTech Connect

    Fox, Kevin

    2012-08-21

    The software provides a simple web api to allow users to request a time window where a file will not be removed from cache. HPSS provides the concept of a "purge lock". When a purge lock is set on a file, the file will not be removed from disk, entering tape only state. A lot of network file protocols assume a file is on disk so it is good to purge lock a file before transferring using one of those protocols. HPSS's purge lock system is very coarse grained though. A file is either purge locked or not. Nothing enforces quotas, timely unlocking of purge locks, or managing the races inherent with multiple users wanting to lock/unlock the same file. The Purge Lock Server lets you, through a simple REST API, specify a list of files to purge lock and an expire time, and the system will ensure things happen properly.

  16. Autoplot and the HAPI Server

    NASA Astrophysics Data System (ADS)

    Faden, J.; Vandegriff, J. D.; Weigel, R. S.

    2016-12-01

    Autoplot was introduced in 2008 as an easy-to-use plotting tool for the space physics community. It reads data from a variety of file resources, such as CDF and HDF files, and a number of specialized data servers, such as the PDS/PPI's DIT-DOS, CDAWeb, and from the University of Iowa's RPWG Das2Server. Each of these servers have optimized methods for transmitting data to display in Autoplot, but require coordination and specialized software to work, limiting Autoplot's ability to access new servers and datasets. Likewise, groups who would like software to access their APIs must either write thier own clients, or publish a specification document in hopes that people will write clients. The HAPI specification was written so that a simple, standard API could be used by both Autoplot and server implementations, to remove these barriers to free flow of time series data. Autoplot's software for communicating with HAPI servers is presented, showing the user interface scientists will use, and how data servers might implement the HAPI specification to provide access to their data. This will also include instructions on how Autoplot is used and installed desktop computers, and used to view data from the RBSP, Juno, and other missions.

  17. WMS Server 2.0

    NASA Technical Reports Server (NTRS)

    Plesea, Lucian; Wood, James F.

    2012-01-01

    This software is a simple, yet flexible server of raster map products, compliant with the Open Geospatial Consortium (OGC) Web Map Service (WMS) 1.1.1 protocol. The server is a full implementation of the OGC WMS 1.1.1 as a fastCGI client and using Geospatial Data Abstraction Library (GDAL) for data access. The server can operate in a proxy mode, where all or part of the WMS requests are done on a back server. The server has explicit support for a colocated tiled WMS, including rapid response of black (no-data) requests. It generates JPEG and PNG images, including 16-bit PNG. The GDAL back-end support allows great flexibility on the data access. The server is a port to a Linux/GDAL platform from the original IRIX/IL platform. It is simpler to configure and use, and depending on the storage format used, it has better performance than other available implementations. The WMS server 2.0 is a high-performance WMS implementation due to the fastCGI architecture. The use of GDAL data back end allows for great flexibility. The configuration is relatively simple, based on a single XML file. It provides scaling and cropping, as well as blending of multiple layers based on layer transparency.

  18. Online Course Model that Fosters Interdisciplinary Collaboration Among Graduate Students

    NASA Astrophysics Data System (ADS)

    deCharon, A.; Repa, J. T.; Companion, C. J.; Taylor, L.

    2016-02-01

    First piloted in Fall 2014, "Broaden the Impacts of Your Research" is a fully asynchronous (i.e., no live or scheduled sessions) online graduate course. This two-credit offering was designed in response to evaluation data from 73 graduate students who participated in four National Science Foundation-funded workshops (deCharon et al., 2013). As a community of practice, students from various scientific disciplines learn about communication and collaboration skills, practice these skills by developing a portfolio of products, and provide feedback on their classmates' products. The course is organized into four sections during the 14-week semester, each with its own set of objectives including: assessing and reducing jargon; engaging in interdisciplinary collaboration; understanding non-scientist audiences' needs; and deconstructing science and connecting to society. The course's quality was assessed through a review of its design by an external evaluator who also gauged its overall efficacy by comparing students' weekly blog posts with the course's goals and objectives. Effectiveness was also evaluated based on students' data from post-semester surveys. Based on these analyses, it has been determined that the course is most appropriate for students who have conducted their initial research and are preparing to communicate it to others and seek additional funding. It exposes students to communications experts through video guest lectures, and it fosters interdisciplinary online collaboration. Participants benefit from employing a variety of online tools to examine and clarify thinking about their own research. Given that the course is online and 100% asynchronous, it is highly flexible and could potentially serve students worldwide. This presentation will focus on the design of "Broaden the Impacts of Your Research," provide evaluation results from both cohorts (i.e., Fall 2014, Fall 2015), and discuss its transferability to other universities or professional societies.

  19. An agent-based model of collective emotions in online communities

    NASA Astrophysics Data System (ADS)

    Schweitzer, F.; Garcia, D.

    2010-10-01

    We develop an agent-based framework to model the emergence of collective emotions, which is applied to online communities. Agent’s individual emotions are described by their valence and arousal. Using the concept of Brownian agents, these variables change according to a stochastic dynamics, which also considers the feedback from online communication. Agents generate emotional information, which is stored and distributed in a field modeling the online medium. This field affects the emotional states of agents in a non-linear manner. We derive conditions for the emergence of collective emotions, observable in a bimodal valence distribution. Dependent on a saturated or a superlinear feedback between the information field and the agent’s arousal, we further identify scenarios where collective emotions only appear once or in a repeated manner. The analytical results are illustrated by agent-based computer simulations. Our framework provides testable hypotheses about the emergence of collective emotions, which can be verified by data from online communities.

  20. Using a strengths model to build an on-line nursing education program.

    PubMed

    Wieck, K Lynn; Alfred, Danita; Haas, Barbara K; Yarbrough, Susan

    2014-01-01

    The on-line environment is the new frontier for academia struggling to define its place in the evolving economy. A concern is how to engage students who maximize their on-line experience and graduate in a timely manner. A strengths model was used as the basis for development of an on-line doctoral nursing program. Upon entering the program, students were given a strengths assessment that focused both students and faculty on the positive attributes students were bringing to their doctoral studies. A positive feedback methodology using on-line discussions in each course was used to support the identified strengths. The optimal picture of a successful entering doctoral student appears to be a person whose top five strengths are learner, achiever, input, connectedness and responsibility. A strengths model promotes a positive learning environment and supports a teacher-learner dynamic where faculty members are encouraged to focus on the students' strengths rather than their challenges.

  1. TAPIR, a web server for the prediction of plant microRNA targets, including target mimics.

    PubMed

    Bonnet, Eric; He, Ying; Billiau, Kenny; Van de Peer, Yves

    2010-06-15

    We present a new web server called TAPIR, designed for the prediction of plant microRNA targets. The server offers the possibility to search for plant miRNA targets using a fast and a precise algorithm. The precise option is much slower but guarantees to find less perfectly paired miRNA-target duplexes. Furthermore, the precise option allows the prediction of target mimics, which are characterized by a miRNA-target duplex having a large loop, making them undetectable by traditional tools. The TAPIR web server can be accessed at: http://bioinformatics.psb.ugent.be/webtools/tapir. Supplementary data are available at Bioinformatics online.

  2. SPAM Detection Server Model Inspired by the Dionaea Muscipula Closure Mechanism: An Alternative Approach for Natural Computing Challenges

    NASA Astrophysics Data System (ADS)

    de Souza Pereira Lopes, Rodrigo Arthur; Carrari R. Lopes, Lia; Mustaro, Pollyana Notargiacomo

    Natural computing has been an increasingly evolving field in the last few years. Focusing on the interesting behaviours offered by nature and biological processes, this work intends to apply the metaphor of the carnivorous plant "Dionaea muscipula" as a complementary defence system against a recurring problem regarding internet and e-mails: spam. The metaphor model presents relevant aspects for further implementation and debate.

  3. Online Teacher Professional Development for Gifted Education: Examining the Impact of a New Pedagogical Model

    ERIC Educational Resources Information Center

    Edinger, Matthew J.

    2017-01-01

    This article theoretically develops and examines the outcomes of a pilot study that evaluates the PACKaGE Model of online Teacher Professional Development (the Model). The Model was created to facilitate positive pedagogical change within gifted education teachers' practice, attitude, collaboration, content knowledge, and goal effectiveness.…

  4. Revision and Validation of a Culturally-Adapted Online Instructional Module Using Edmundson's CAP Model: A DBR Study

    ERIC Educational Resources Information Center

    Tapanes, Marie A.

    2011-01-01

    In the present study, the Cultural Adaptation Process Model was applied to an online module to include adaptations responsive to the online students' culturally-influenced learning styles and preferences. The purpose was to provide the online learners with a variety of course material presentations, where the e-learners had the opportunity to…

  5. Revision and Validation of a Culturally-Adapted Online Instructional Module Using Edmundson's CAP Model: A DBR Study

    ERIC Educational Resources Information Center

    Tapanes, Marie A.

    2011-01-01

    In the present study, the Cultural Adaptation Process Model was applied to an online module to include adaptations responsive to the online students' culturally-influenced learning styles and preferences. The purpose was to provide the online learners with a variety of course material presentations, where the e-learners had the opportunity to…

  6. Toward a Social Conflict Evolution Model: Examining the Adverse Power of Conflictual Social Interaction in Online Learning

    ERIC Educational Resources Information Center

    Xie, Kui; Miller, Nicole C.; Allison, Justin R.

    2013-01-01

    This case study examined an authentic online learning phenomenon where social conflict, including harsh critique and negative tone, weaved throughout peer-moderated online discussions in an online class. Opening coding and content analysis were performed on 1306 message units and course artifacts. The results revealed that a model of social…

  7. Toward a Social Conflict Evolution Model: Examining the Adverse Power of Conflictual Social Interaction in Online Learning

    ERIC Educational Resources Information Center

    Xie, Kui; Miller, Nicole C.; Allison, Justin R.

    2013-01-01

    This case study examined an authentic online learning phenomenon where social conflict, including harsh critique and negative tone, weaved throughout peer-moderated online discussions in an online class. Opening coding and content analysis were performed on 1306 message units and course artifacts. The results revealed that a model of social…

  8. KFC Server: interactive forecasting of protein interaction hot spots.

    PubMed

    Darnell, Steven J; LeGault, Laura; Mitchell, Julie C

    2008-07-01

    The KFC Server is a web-based implementation of the KFC (Knowledge-based FADE and Contacts) model-a machine learning approach for the prediction of binding hot spots, or the subset of residues that account for most of a protein interface's; binding free energy. The server facilitates the automated analysis of a user submitted protein-protein or protein-DNA interface and the visualization of its hot spot predictions. For each residue in the interface, the KFC Server characterizes its local structural environment, compares that environment to the environments of experimentally determined hot spots and predicts if the interface residue is a hot spot. After the computational analysis, the user can visualize the results using an interactive job viewer able to quickly highlight predicted hot spots and surrounding structural features within the protein structure. The KFC Server is accessible at http://kfc.mitchell-lab.org.

  9. The SDSS data archive server

    SciTech Connect

    Neilsen, Eric H., Jr.; /Fermilab

    2007-10-01

    The Sloan Digital Sky Survey (SDSS) Data Archive Server (DAS) provides public access to data files produced by the SDSS data reduction pipeline. This article discusses challenges in public distribution of data of this volume and complexity, and how the project addressed them. The Sloan Digital Sky Survey (SDSS)1 is an astronomical survey of covering roughly one quarter of the night sky. It contains images of this area, a catalog of almost 300 million objects detected in those images, and spectra of more than a million of these objects. The catalog of objects includes a variety of data on each object. These data include not only basic information but also fit parameters for a variety of models, classifications by sophisticated object classification algorithms, statistical parameters, and more. If the survey contains the spectrum of an object, the catalog includes a variety of other parameters derived from its spectrum. Data processing and catalog generation, described more completely in the SDSS Early Data Release2 paper, consists of several stages: collection of imaging data, processing of imaging data, selection of spectroscopic targets from catalogs generated from the imaging data, collection of spectroscopic data, processing of spectroscopic data, and loading of processed data into a database. Each of these stages is itself a complex process. For example, the software that processes the imaging data determines and removes some instrumental signatures in the raw images to create 'corrected frames', models the point spread function, models and removes the sky background, detects objects, measures object positions, measures the radial profile and other morphological parameters for each object, measures the brightness of each object using a variety of methods, classifies the objects, calibrates the brightness measurements against survey standards, and produces a variety of quality assurance plots and diagnostic tables. The complexity of the spectroscopic data

  10. Assessment of Risk Communication about Undercooked Hamburgers by Restaurant Servers.

    PubMed

    Thomas, Ellen M; Binder, Andrew R; McLAUGHLIN, Anne; Jaykus, Lee-Ann; Hanson, Dana; Powell, Douglas; Chapman, Benjamin

    2016-12-01

    According to the U.S. Food and Drug Administration 2013 Model Food Code, it is the duty of a food establishment to disclose and remind consumers of risk when ordering undercooked food such as ground beef. The purpose of this study was to explore actual risk communication behaviors of food establishment servers. Secret shoppers visited 265 restaurants in seven geographic locations across the United States, ordered medium rare burgers, and collected and coded risk information from chain and independent restaurant menus and from server responses. The majority of servers reported an unreliable method of doneness (77%) or other incorrect information (66%) related to burger doneness and safety. These results indicate major gaps in server knowledge and risk communication, and the current risk communication language in the Model Food Code does not sufficiently fill these gaps. The question is "should servers even be acting as risk communicators?" There are numerous challenges associated with this practice, including high turnover rates, limited education, and the high stress environment based on pleasing a customer. If servers are designated as risk communicators, food establishment staff should be adequately trained and provided with consumer advisory messages that are accurate, audience appropriate, and delivered in a professional manner so that customers can make informed food safety decisions.

  11. Improving Website Hyperlink Structure Using Server Logs

    PubMed Central

    Paranjape, Ashwin; West, Robert; Zia, Leila; Leskovec, Jure

    2016-01-01

    Good websites should be easy to navigate via hyperlinks, yet maintaining a high-quality link structure is difficult. Identifying pairs of pages that should be linked may be hard for human editors, especially if the site is large and changes frequently. Further, given a set of useful link candidates, the task of incorporating them into the site can be expensive, since it typically involves humans editing pages. In the light of these challenges, it is desirable to develop data-driven methods for automating the link placement task. Here we develop an approach for automatically finding useful hyperlinks to add to a website. We show that passively collected server logs, beyond telling us which existing links are useful, also contain implicit signals indicating which nonexistent links would be useful if they were to be introduced. We leverage these signals to model the future usefulness of yet nonexistent links. Based on our model, we define the problem of link placement under budget constraints and propose an efficient algorithm for solving it. We demonstrate the effectiveness of our approach by evaluating it on Wikipedia, a large website for which we have access to both server logs (used for finding useful new links) and the complete revision history (containing a ground truth of new links). As our method is based exclusively on standard server logs, it may also be applied to any other website, as we show with the example of the biomedical research site Simtk. PMID:28345077

  12. A Path Model of School Violence Perpetration: Introducing Online Game Addiction as a New Risk Factor.

    PubMed

    Kim, Jae Yop; Lee, Jeen Suk; Oh, Sehun

    2015-08-10

    Drawing on the cognitive information-processing model of aggression and the general aggression model, we explored why adolescents become addicted to online games and how their immersion in online games affects school violence perpetration (SVP). For this purpose, we conducted statistical analyses on 1,775 elementary and middle school students who resided in northern districts of Seoul, South Korea. The results validated the proposed structural equation model and confirmed the statistical significance of the structural paths from the variables; that is, the paths from child abuse and self-esteem to SVP were significant. The levels of self-esteem and child abuse victimization affected SVP, and this effect was mediated by online game addiction (OGA). Furthermore, a multigroup path analysis showed significant gender differences in the path coefficients of the proposed model, indicating that gender exerted differential effects on adolescents' OGA and SVP. Based on these results, prevention and intervention methods to curb violence in schools have been proposed.

  13. On-line and Model-based Approaches to the Visual Control of Action

    PubMed Central

    Zhao, Huaiyong; Warren, William H.

    2014-01-01

    Two general approaches to the visual control of action have emerged in last few decades, known as the on-line and model-based approaches. The key difference between them is whether action is controlled by current visual information or on the basis of an internal world model. In this paper, we evaluate three hypotheses: strong on-line control, strong model-based control, and a hybrid solution that combines on-line control with weak off-line strategies. We review experimental research on the control of locomotion and manual actions, which indicates that (a) an internal world model is neither sufficient nor necessary to control action at normal levels of performance; (b) current visual information is necessary and sufficient to control action at normal levels; and (c) under certain conditions (e.g. occlusion) action is controlled by less accurate, simple strategies such as heuristics, visual-motor mappings, or spatial memory. We conclude that the strong model-based hypothesis is not sustainable. Action is normally controlled on-line when current information is available, consistent with the strong on-line control hypothesis. In exceptional circumstances, action is controlled by weak, context-specific, off-line strategies. This hybrid solution is comprehensive, parsimonious, and able to account for a variety of tasks under a range of visual conditions. PMID:25454700

  14. Supplemental Instruction Online: As Effective as the Traditional Face-to-Face Model?

    NASA Astrophysics Data System (ADS)

    Hizer, Suzanne E.; Schultz, P. W.; Bray, Richard

    2016-10-01

    Supplemental Instruction (SI) is a well-recognized model of academic assistance with a history of empirical evidence demonstrating increases in student grades and decreases in failure rates across many higher education institutions. However, as college students become more accustomed to learning in online venues, what is not known is whether an SI program offered online could benefit students similarly to SI sessions that occur in face-to-face settings. The in-person (traditional) SI program at California State University San Marcos has demonstrated increases in grades and lower fail rates for courses being supported in science and math. Students enrolled in four biology courses who participated in online SI received increases in academic performance similar to the students in the courses who attended traditional SI. Both the online and traditional SI participating students had higher course grades and lower fail rates as compared to students who did not participate in either form of SI. Self-selection, as measured by past cumulative college grade point average, did not differ between students who attended either form of SI or who did not attend. Student perceptions of online SI were generally positive and appeared to offer an alternative path to receive this valuable academic assistance for some students. Overall, results are promising that the highly effective traditional model can be translated to an online environment.

  15. Supplemental Instruction Online: As Effective as the Traditional Face-to-Face Model?

    NASA Astrophysics Data System (ADS)

    Hizer, Suzanne E.; Schultz, P. W.; Bray, Richard

    2017-02-01

    Supplemental Instruction (SI) is a well-recognized model of academic assistance with a history of empirical evidence demonstrating increases in student grades and decreases in failure rates across many higher education institutions. However, as college students become more accustomed to learning in online venues, what is not known is whether an SI program offered online could benefit students similarly to SI sessions that occur in face-to-face settings. The in-person (traditional) SI program at California State University San Marcos has demonstrated increases in grades and lower fail rates for courses being supported in science and math. Students enrolled in four biology courses who participated in online SI received increases in academic performance similar to the students in the courses who attended traditional SI. Both the online and traditional SI participating students had higher course grades and lower fail rates as compared to students who did not participate in either form of SI. Self-selection, as measured by past cumulative college grade point average, did not differ between students who attended either form of SI or who did not attend. Student perceptions of online SI were generally positive and appeared to offer an alternative path to receive this valuable academic assistance for some students. Overall, results are promising that the highly effective traditional model can be translated to an online environment.

  16. KOSMOS: a universal morph server for nucleic acids, proteins and their complexes.

    PubMed

    Seo, Sangjae; Kim, Moon Ki

    2012-07-01

    KOSMOS is the first online morph server to be able to address the structural dynamics of DNA/RNA, proteins and even their complexes, such as ribosomes. The key functions of KOSMOS are the harmonic and anharmonic analyses of macromolecules. In the harmonic analysis, normal mode analysis (NMA) based on an elastic network model (ENM) is performed, yielding vibrational modes and B-factor calculations, which provide insight into the potential biological functions of macromolecules based on their structural features. Anharmonic analysis involving elastic network interpolation (ENI) is used to generate plausible transition pathways between two given conformations by optimizing a topology-oriented cost function that guarantees a smooth transition without steric clashes. The quality of the computed pathways is evaluated based on their various facets, including topology, energy cost and compatibility with the NMA results. There are also two unique features of KOSMOS that distinguish it from other morph servers: (i) the versatility in the coarse-graining methods and (ii) the various connection rules in the ENM. The models enable us to analyze macromolecular dynamics with the maximum degrees of freedom by combining a variety of ENMs from full-atom to coarse-grained, backbone and hybrid models with one connection rule, such as distance-cutoff, number-cutoff or chemical-cutoff. KOSMOS is available at http://bioengineering.skku.ac.kr/kosmos.

  17. KOSMOS: a universal morph server for nucleic acids, proteins and their complexes

    PubMed Central

    Seo, Sangjae; Kim, Moon Ki

    2012-01-01

    KOSMOS is the first online morph server to be able to address the structural dynamics of DNA/RNA, proteins and even their complexes, such as ribosomes. The key functions of KOSMOS are the harmonic and anharmonic analyses of macromolecules. In the harmonic analysis, normal mode analysis (NMA) based on an elastic network model (ENM) is performed, yielding vibrational modes and B-factor calculations, which provide insight into the potential biological functions of macromolecules based on their structural features. Anharmonic analysis involving elastic network interpolation (ENI) is used to generate plausible transition pathways between two given conformations by optimizing a topology-oriented cost function that guarantees a smooth transition without steric clashes. The quality of the computed pathways is evaluated based on their various facets, including topology, energy cost and compatibility with the NMA results. There are also two unique features of KOSMOS that distinguish it from other morph servers: (i) the versatility in the coarse-graining methods and (ii) the various connection rules in the ENM. The models enable us to analyze macromolecular dynamics with the maximum degrees of freedom by combining a variety of ENMs from full-atom to coarse-grained, backbone and hybrid models with one connection rule, such as distance-cutoff, number-cutoff or chemical-cutoff. KOSMOS is available at http://bioengineering.skku.ac.kr/kosmos. PMID:22669912

  18. Compute Server Performance Results

    NASA Technical Reports Server (NTRS)

    Stockdale, I. E.; Barton, John; Woodrow, Thomas (Technical Monitor)

    1994-01-01

    Parallel-vector supercomputers have been the workhorses of high performance computing. As expectations of future computing needs have risen faster than projected vector supercomputer performance, much work has been done investigating the feasibility of using Massively Parallel Processor systems as supercomputers. An even more recent development is the availability of high performance workstations which have the potential, when clustered together, to replace parallel-vector systems. We present a systematic comparison of floating point performance and price-performance for various compute server systems. A suite of highly vectorized programs was run on systems including traditional vector systems such as the Cray C90, and RISC workstations such as the IBM RS/6000 590 and the SGI R8000. The C90 system delivers 460 million floating point operations per second (FLOPS), the highest single processor rate of any vendor. However, if the price-performance ration (PPR) is considered to be most important, then the IBM and SGI processors are superior to the C90 processors. Even without code tuning, the IBM and SGI PPR's of 260 and 220 FLOPS per dollar exceed the C90 PPR of 160 FLOPS per dollar when running our highly vectorized suite,

  19. Modeling the Biodegradability of Chemical Compounds Using the Online CHEmical Modeling Environment (OCHEM)

    PubMed Central

    Vorberg, Susann

    2013-01-01

    Abstract Biodegradability describes the capacity of substances to be mineralized by free‐living bacteria. It is a crucial property in estimating a compound’s long‐term impact on the environment. The ability to reliably predict biodegradability would reduce the need for laborious experimental testing. However, this endpoint is difficult to model due to unavailability or inconsistency of experimental data. Our approach makes use of the Online Chemical Modeling Environment (OCHEM) and its rich supply of machine learning methods and descriptor sets to build classification models for ready biodegradability. These models were analyzed to determine the relationship between characteristic structural properties and biodegradation activity. The distinguishing feature of the developed models is their ability to estimate the accuracy of prediction for each individual compound. The models developed using seven individual descriptor sets were combined in a consensus model, which provided the highest accuracy. The identified overrepresented structural fragments can be used by chemists to improve the biodegradability of new chemical compounds. The consensus model, the datasets used, and the calculated structural fragments are publicly available at http://ochem.eu/article/31660. PMID:27485201

  20. Comparing Server Energy Use and Efficiency Using Small Sample Sizes

    SciTech Connect

    Coles, Henry C.; Qin, Yong; Price, Phillip N.

    2014-11-01

    This report documents a demonstration that compared the energy consumption and efficiency of a limited sample size of server-type IT equipment from different manufacturers by measuring power at the server power supply power cords. The results are specific to the equipment and methods used. However, it is hoped that those responsible for IT equipment selection can used the methods described to choose models that optimize energy use efficiency. The demonstration was conducted in a data center at Lawrence Berkeley National Laboratory in Berkeley, California. It was performed with five servers of similar mechanical and electronic specifications; three from Intel and one each from Dell and Supermicro. Server IT equipment is constructed using commodity components, server manufacturer-designed assemblies, and control systems. Server compute efficiency is constrained by the commodity component specifications and integration requirements. The design freedom, outside of the commodity component constraints, provides room for the manufacturer to offer a product with competitive efficiency that meets market needs at a compelling price. A goal of the demonstration was to compare and quantify the server efficiency for three different brands. The efficiency is defined as the average compute rate (computations per unit of time) divided by the average energy consumption rate. The research team used an industry standard benchmark software package to provide a repeatable software load to obtain the compute rate and provide a variety of power consumption levels. Energy use when the servers were in an idle state (not providing computing work) were also measured. At high server compute loads, all brands, using the same key components (processors and memory), had similar results; therefore, from these results, it could not be concluded that one brand is more efficient than the other brands. The test results show that the power consumption variability caused by the key components as a

  1. Development of an Instructional Model for Online Task-Based Interactive Listening for EFL Learners

    ERIC Educational Resources Information Center

    Tian, Xingbin; Suppasetseree, Suksan

    2013-01-01

    College English in China has shifted from cultivating reading ability to comprehensive communicative abilities with an emphasis on listening and speaking. For this reason, new teaching models should be built on modern information technology. However, little research on developing models for the online teaching of listening skills has been…

  2. Factors Motivating Preservice Teachers for Online Learning within the Context of ARCS Motivation Model

    ERIC Educational Resources Information Center

    Izmirli, Serkan; Sahin Izmirli, Ozden

    2015-01-01

    The purpose of this study was to determine the factors motivating pre-service teachers for online learning within the context of ARCS motivation model. The study, in which the phenomenology model was used, was carried out with 52 pre-service teachers attending the department of Computer Education and Instructional Technologies at the Education…

  3. Evaluating Online Instruction: Adapting a Training Model to E-Learning in Higher Education.

    ERIC Educational Resources Information Center

    Hallett, Karen; Essex, Christopher

    This paper presents a model for the evaluation of postsecondary online distance education courses and programs. To better address the unique nature and audience for these courses and programs, and the related institutional needs for assessing their success or failure, the focus is on a model from corporate training that provides a comprehensive,…

  4. Using the Constructivist Tridimensional Design Model for Online Continuing Education for Health Care Clinical Faculty

    ERIC Educational Resources Information Center

    Seo, Kay Kyeong-Ju; Engelhard, Chalee

    2014-01-01

    This article presents a new paradigm for continuing education of Clinical Instructors (CIs): the Constructivist Tridimensional (CTD) model for the design of an online curriculum. Based on problem-based learning, self-regulated learning, and adult learning theory, the CTD model was designed to facilitate interactive, collaborative, and authentic…

  5. OTLA: A New Model for Online Teaching, Learning and Assessment in Higher Education

    ERIC Educational Resources Information Center

    Ghilay, Yaron; Ghilay, Ruth

    2013-01-01

    The study examined a new asynchronous model for online teaching, learning and assessment, called OTLA. It is designed for higher-education institutions and is based on LMS (Learning Management System) as well as other relevant IT tools. The new model includes six digital basic components: text, hypertext, text reading, lectures (voice/video),…

  6. RISK ASSESSMENT ANALYSES USING EPA'S ON-LINE SITE-SPECIFIC TRANSPORT MODELS AND FIELD DATA

    EPA Science Inventory

    EPA has developed a suite of on-line calculators and transport models to aid in risk assessment for subsurface contamination. The calculators (www.epa.gov/athens/onsite) provide several levels of tools and data. These include tools for generating commonly-used model input param...

  7. RISK ASSESSMENT ANALYSES USING EPA'S ON-LINE SITE-SPECIFIC TRANSPORT MODELS AND FIELD DATA

    EPA Science Inventory

    EPA has developed a suite of on-line calculators and transport models to aid in risk assessment for subsurface contamination. The calculators (www.epa.gov/athens/onsite) provide several levels of tools and data. These include tools for generating commonly-used model input param...

  8. Using the Constructivist Tridimensional Design Model for Online Continuing Education for Health Care Clinical Faculty

    ERIC Educational Resources Information Center

    Seo, Kay Kyeong-Ju; Engelhard, Chalee

    2014-01-01

    This article presents a new paradigm for continuing education of Clinical Instructors (CIs): the Constructivist Tridimensional (CTD) model for the design of an online curriculum. Based on problem-based learning, self-regulated learning, and adult learning theory, the CTD model was designed to facilitate interactive, collaborative, and authentic…

  9. An online trajectory module (version 1.0) for the nonhydrostatic numerical weather prediction model COSMO

    NASA Astrophysics Data System (ADS)

    Miltenberger, A. K.; Pfahl, S.; Wernli, H.

    2013-11-01

    A module to calculate online trajectories has been implemented into the nonhydrostatic limited-area weather prediction and climate model COSMO. Whereas offline trajectories are calculated with wind fields from model output, which is typically available every one to six hours, online trajectories use the simulated resolved wind field at every model time step (typically less than a minute) to solve the trajectory equation. As a consequence, online trajectories much better capture the short-term temporal fluctuations of the wind field, which is particularly important for mesoscale flows near topography and convective clouds, and they do not suffer from temporal interpolation errors between model output times. The numerical implementation of online trajectories in the COSMO-model is based upon an established offline trajectory tool and takes full account of the horizontal domain decomposition that is used for parallelization of the COSMO-model. Although a perfect workload balance cannot be achieved for the trajectory module (due to the fact that trajectory positions are not necessarily equally distributed over the model domain), the additional computational costs are found to be fairly small for the high-resolution simulations described in this paper. The computational costs may, however, vary strongly depending on the number of trajectories and trace variables. Various options have been implemented to initialize online trajectories at different locations and times during the model simulation. As a first application of the new COSMO-model module, an Alpine north foehn event in summer 1987 has been simulated with horizontal resolutions of 2.2, 7 and 14 km. It is shown that low-tropospheric trajectories calculated offline with one- to six-hourly wind fields can significantly deviate from trajectories calculated online. Deviations increase with decreasing model grid spacing and are particularly large in regions of deep convection and strong orographic flow distortion. On

  10. From honeybees to Internet servers: biomimicry for distributed management of Internet hosting centers.

    PubMed

    Nakrani, Sunil; Tovey, Craig

    2007-12-01

    An Internet hosting center hosts services on its server ensemble. The center must allocate servers dynamically amongst services to maximize revenue earned from hosting fees. The finite server ensemble, unpredictable request arrival behavior and server reallocation cost make server allocation optimization difficult. Server allocation closely resembles honeybee forager allocation amongst flower patches to optimize nectar influx. The resemblance inspires a honeybee biomimetic algorithm. This paper describes details of the honeybee self-organizing model in terms of information flow and feedback, analyzes the homology between the two problems and derives the resulting biomimetic algorithm for hosting centers. The algorithm is assessed for effectiveness and adaptiveness by comparative testing against benchmark and conventional algorithms. Computational results indicate that the new algorithm is highly adaptive to widely varying external environments and quite competitive against benchmark assessment algorithms. Other swarm intelligence applications are briefly surveyed, and some general speculations are offered regarding their various degrees of success.

  11. Distributed control system for demand response by servers

    NASA Astrophysics Data System (ADS)

    Hall, Joseph Edward

    Within the broad topical designation of smart grid, research in demand response, or demand-side management, focuses on investigating possibilities for electrically powered devices to adapt their power consumption patterns to better match generation and more efficiently integrate intermittent renewable energy sources, especially wind. Devices such as battery chargers, heating and cooling systems, and computers can be controlled to change the time, duration, and magnitude of their power consumption while still meeting workload constraints such as deadlines and rate of throughput. This thesis presents a system by which a computer server, or multiple servers in a data center, can estimate the power imbalance on the electrical grid and use that information to dynamically change the power consumption as a service to the grid. Implementation on a testbed demonstrates the system with a hypothetical but realistic usage case scenario of an online video streaming service in which there are workloads with deadlines (high-priority) and workloads without deadlines (low-priority). The testbed is implemented with real servers, estimates the power imbalance from the grid frequency with real-time measurements of the live outlet, and uses a distributed, real-time algorithm to dynamically adjust the power consumption of the servers based on the frequency estimate and the throughput of video transcoder workloads. Analysis of the system explains and justifies multiple design choices, compares the significance of the system in relation to similar publications in the literature, and explores the potential impact of the system.

  12. Does trust promote more teamwork? Modeling online game players' teamwork using team experience as a moderator.

    PubMed

    Lee, Chun-Chia; Chang, Jen-Wei

    2013-11-01

    The need for teamwork has grown significantly in today's organizations. Especially for online game communities, teamwork is an important means of online game players' engagement. This study aims to investigate the impacts of trust on players' teamwork with affective commitment and normative commitment as mediators. Furthermore, this research includes team experience as a moderator to compare the difference between different player groups. A model was proposed and tested on 296 online game players' data using structural equation modeling. Findings revealed that team experience moderated the relationship between trust and teamwork. The results indicated that trust promotes more teamwork only for players with high experience through affective commitment than those who with low experience. Implications of the findings are discussed.

  13. Sensation Seeking and Online Gaming Addiction in Adolescents: A Moderated Mediation Model of Positive Affective Associations and Impulsivity.

    PubMed

    Hu, Jianping; Zhen, Shuangju; Yu, Chengfu; Zhang, Qiuyan; Zhang, Wei

    2017-01-01

    Based on the Dual Systems Model (Somerville et al., 2010; Steinberg, 2010a) and the biosocial-affect model (Romer and Hennessy, 2007) of adolescent sensation seeking and problem behaviors, the present study examined how (affective associations with online games as a mediator) and when (impulsivity as a moderator) did sensation seeking influence online gaming addiction in adolescence. A total of 375 Chinese male adolescents (mean age = 16.02 years, SD = 0.85) from southern China completed anonymous questionnaires regarding sensation seeking, positive affective associations with online games, impulsivity, and online gaming addiction. Our findings revealed that sensation seeking, positive affective associations with online games and impulsivity were each significantly and positively associated with online gaming addiction in adolescents. Positive affective associations mediated the relationship between sensation seeking and online gaming addiction. Further, impulsivity moderated the relationship between positive affective associations and online gaming addiction, such that the association between positive affective association and online gaming addiction was stronger for high than for low impulsivity adolescents. These findings underscore the importance of integrating the biosocial-affect model and the Dual Systems Model to understand how and when sensation seeking impacts adolescent online gaming addiction.

  14. Sensation Seeking and Online Gaming Addiction in Adolescents: A Moderated Mediation Model of Positive Affective Associations and Impulsivity

    PubMed Central

    Hu, Jianping; Zhen, Shuangju; Yu, Chengfu; Zhang, Qiuyan; Zhang, Wei

    2017-01-01

    Based on the Dual Systems Model (Somerville et al., 2010; Steinberg, 2010a) and the biosocial-affect model (Romer and Hennessy, 2007) of adolescent sensation seeking and problem behaviors, the present study examined how (affective associations with online games as a mediator) and when (impulsivity as a moderator) did sensation seeking influence online gaming addiction in adolescence. A total of 375 Chinese male adolescents (mean age = 16.02 years, SD = 0.85) from southern China completed anonymous questionnaires regarding sensation seeking, positive affective associations with online games, impulsivity, and online gaming addiction. Our findings revealed that sensation seeking, positive affective associations with online games and impulsivity were each significantly and positively associated with online gaming addiction in adolescents. Positive affective associations mediated the relationship between sensation seeking and online gaming addiction. Further, impulsivity moderated the relationship between positive affective associations and online gaming addiction, such that the association between positive affective association and online gaming addiction was stronger for high than for low impulsivity adolescents. These findings underscore the importance of integrating the biosocial-affect model and the Dual Systems Model to understand how and when sensation seeking impacts adolescent online gaming addiction. PMID:28529494

  15. Fault-tolerant PACS server

    NASA Astrophysics Data System (ADS)

    Cao, Fei; Liu, Brent J.; Huang, H. K.; Zhou, Michael Z.; Zhang, Jianguo; Zhang, X. C.; Mogel, Greg T.

    2002-05-01

    Failure of a PACS archive server could cripple an entire PACS operation. Last year we demonstrated that it was possible to design a fault-tolerant (FT) server with 99.999% uptime. The FT design was based on a triple modular redundancy with a simple majority vote to automatically detect and mask a faulty module. The purpose of this presentation is to report on its continuous developments in integrating with external mass storage devices, and to delineate laboratory failover experiments. An FT PACS Simulator with generic PACS software has been used in the experiment. To simulate a PACS clinical operation, image examinations are transmitted continuously from the modality simulator to the DICOM gateway and then to the FT PACS server and workstations. The hardware failures in network, FT server module, disk, RAID, and DLT are manually induced to observe the failover recovery of the FT PACS to resume its normal data flow. We then test and evaluate the FT PACS server in its reliability, functionality, and performance.

  16. Remodeling: Building on the Strengths of Existing Course Development Models to Present a Student-Centered Model for Online Learning for Community Colleges

    ERIC Educational Resources Information Center

    Pheils, Denise M.

    2010-01-01

    This qualitative study explored the elements affecting an online student's performance and ability to succeed in an online course by offering a synthesized and enhanced model for online course development that considers the student holistically. The phenomenological study is grounded in the constructivist approach to learning and focused on the…

  17. Creating a GIS data server on the World Wide Web: The GISST example

    SciTech Connect

    Pace, P.J.; Evers, T.K.

    1996-01-01

    In an effort to facilitate user access to Geographic Information Systems (GIS) data, the GIS and Computer Modeling Group from the Computational Physics and Engineering Division at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee (TN), has developed a World Wide Web server named GISST. The server incorporates a highly interactive and dynamic forms-based interface to browse and download a variety of GIS data types. This paper describes the server`s design considerations, development, resulting implementation and future enhancements.

  18. ON-LINE CALCULATOR: JOHNSON ETTINGER VAPOR INTRUSION MODEL

    EPA Science Inventory

    On-Site was developed to provide modelers and model reviewers with prepackaged tools ("calculators") for performing site assessment calculations. The philosophy behind OnSite is that the convenience of the prepackaged calculators helps provide consistency for simple calculations,...

  19. ON-LINE CALCULATOR: FORWARD CALCULATION JOHNSON ETTINGER MODEL

    EPA Science Inventory

    On-Site was developed to provide modelers and model reviewers with prepackaged tools ("calculators") for performing site assessment calculations. The philosophy behind OnSite is that the convenience of the prepackaged calculators helps provide consistency for simple calculations,...

  20. ON-LINE CALCULATOR: JOHNSON ETTINGER VAPOR INTRUSION MODEL

    EPA Science Inventory

    On-Site was developed to provide modelers and model reviewers with prepackaged tools ("calculators") for performing site assessment calculations. The philosophy behind OnSite is that the convenience of the prepackaged calculators helps provide consistency for simple calculations,...

  1. ON-LINE CALCULATOR: FORWARD CALCULATION JOHNSON ETTINGER MODEL

    EPA Science Inventory

    On-Site was developed to provide modelers and model reviewers with prepackaged tools ("calculators") for performing site assessment calculations. The philosophy behind OnSite is that the convenience of the prepackaged calculators helps provide consistency for simple calculations,...

  2. Required Collaborative Work in Online Courses: A Predictive Modeling Approach

    ERIC Educational Resources Information Center

    Smith, Marlene A.; Kellogg, Deborah L.

    2015-01-01

    This article describes a predictive model that assesses whether a student will have greater perceived learning in group assignments or in individual work. The model produces correct classifications 87.5% of the time. The research is notable in that it is the first in the education literature to adopt a predictive modeling methodology using data…

  3. Required Collaborative Work in Online Courses: A Predictive Modeling Approach

    ERIC Educational Resources Information Center

    Smith, Marlene A.; Kellogg, Deborah L.

    2015-01-01

    This article describes a predictive model that assesses whether a student will have greater perceived learning in group assignments or in individual work. The model produces correct classifications 87.5% of the time. The research is notable in that it is the first in the education literature to adopt a predictive modeling methodology using data…

  4. Using the Community of Inquiry Model to Investigate Students' Knowledge Construction in Asynchronous Online Discussions

    ERIC Educational Resources Information Center

    Liu, Chien-Jen; Yang, Shu Ching

    2014-01-01

    This study used the Community of Inquiry (CoI) model proposed by Garrison to investigate students' level of knowledge construction in asynchronous discussions. The participants included 36 senior students (27 males) majoring in information management. The students attended 18 weeks of an online information ethics course. In this study, four types…

  5. The Development of a Content Analysis Model for Assessing Students' Cognitive Learning in Asynchronous Online Discussions

    ERIC Educational Resources Information Center

    Yang, Dazhi; Richardson, Jennifer C.; French, Brian F.; Lehman, James D.

    2011-01-01

    The purpose of this study was to develop and validate a content analysis model for assessing students' cognitive learning in asynchronous online discussions. It adopted a fully mixed methods design, in which qualitative and quantitative methods were employed sequentially for data analysis and interpretation. Specifically, the design was a…

  6. Supplemental Instruction Online: As Effective as the Traditional Face-to-Face Model?

    ERIC Educational Resources Information Center

    Hizer, Suzanne E.; Schultz, P. W.; Bray, Richard

    2017-01-01

    Supplemental Instruction (SI) is a well-recognized model of academic assistance with a history of empirical evidence demonstrating increases in student grades and decreases in failure rates across many higher education institutions. However, as college students become more accustomed to learning in online venues, what is not known is whether an SI…

  7. Modelling and Managing Learner Satisfaction: Use of Learner Feedback to Enhance Blended and Online Learning Experience

    ERIC Educational Resources Information Center

    Li, Nai; Marsh, Vicky; Rienties, Bart

    2016-01-01

    A key concern for most institutions and instructors is whether students are satisfied with their learning experience. However, relatively few studies have unpacked what the key drivers for learner satisfaction are in blended and online courses. Using logistical regression modelling, learner satisfaction data of 62,986 learners in 401 undergraduate…

  8. A Distributed Model for Managing Academic Staff in an International Online Academic Programme

    ERIC Educational Resources Information Center

    Kalman, Yoram M.; Leng, Paul H.

    2007-01-01

    Online delivery of programmes of Higher Education typically involves a distributed community of students interacting with a single university site, at which the teachers, learning resources and administration of the programme are located. The alternative model, of a fully "Virtual University", which assumes no physical campus, poses…

  9. The Development of a Content Analysis Model for Assessing Students' Cognitive Learning in Asynchronous Online Discussions

    ERIC Educational Resources Information Center

    Yang, Dazhi; Richardson, Jennifer C.; French, Brian F.; Lehman, James D.

    2011-01-01

    The purpose of this study was to develop and validate a content analysis model for assessing students' cognitive learning in asynchronous online discussions. It adopted a fully mixed methods design, in which qualitative and quantitative methods were employed sequentially for data analysis and interpretation. Specifically, the design was a…

  10. A Model for Online Support in Classroom Management: Perceptions of Beginning Teachers

    ERIC Educational Resources Information Center

    Baker, Credence; Gentry, James; Larmer, William

    2016-01-01

    Classroom management is a challenge for beginning teachers. To address this challenge, a model to provide support for beginning teachers was developed, consisting of a one-day workshop on classroom management, followed with online support extending over eight weeks. Specific classroom management strategies included (a) developing a foundation…

  11. Designing Online Learning for Developing Pre-Service Teachers' Capabilities in Mathematical Modelling and Applications

    ERIC Educational Resources Information Center

    Geiger, Vince; Date-Huxtable, Liz; Ahlip, Rehez; Herberstein, Marie; Jones, D. Heath; May, E. Julian; Rylands, Leanne; Wright, Ian; Mulligan, Joanne

    2016-01-01

    The purpose of this paper is to describe the processes utilised to develop an online learning module within the Opening Real Science (ORS) project--"Modelling the present: Predicting the future." The module was realised through an interdisciplinary collaboration, among mathematicians, scientists and mathematics and science educators that…

  12. Phenomenological Study of Business Models Used to Scale Online Enrollment at Institutions of Higher Education

    ERIC Educational Resources Information Center

    Williams, Dana E.

    2012-01-01

    The purpose of this qualitative phenomenological study was to explore factors for selecting a business model for scaling online enrollment by institutions of higher education. The goal was to explore the lived experiences of academic industry experts involved in the selection process. The research question for this study was: What were the lived…

  13. Taking the Epistemic Step: Toward a Model of On-Line Access to Conversational Implicatures

    ERIC Educational Resources Information Center

    Breheny, Richard; Ferguson, Heather J.; Katsos, Napoleon

    2013-01-01

    There is a growing body of evidence showing that conversational implicatures are rapidly accessed in incremental utterance interpretation. To date, studies showing incremental access have focussed on implicatures related to linguistic triggers, such as "some" and "or". We discuss three kinds of on-line model that can account for this data. A model…

  14. Mentoring Professors: A Model for Developing Quality Online Instructors and Courses in Higher Education

    ERIC Educational Resources Information Center

    Barczyk, Casimir; Buckenmeyer, Janet; Feldman, Lori

    2010-01-01

    This article presents a four-stage model for mentoring faculty in higher education to deliver high quality online instruction. It provides a timeline that shows the stages of program implementation. Known as the Distance Education Mentoring Program, its major outcomes include certified instructors, student achievement, and the attainment of a…

  15. The Practitioner's Model: Designing a Professional Development Program for Online Teaching

    ERIC Educational Resources Information Center

    Weaver, Debbi; Robbie, Diane; Borland, Rosemary

    2008-01-01

    This article describes the experiences of staff responsible for developing and delivering professional development (PD) in online teaching in three universities in the same Australian state. Each university draws on a similar pool of staff and students, and operates under the same government regulations, but has used different models of policy and…

  16. The POD Model: Using Communities of Practice Theory to Conceptualise Student Teachers' Professional Learning Online

    ERIC Educational Resources Information Center

    Clarke, Linda

    2009-01-01

    This paper focuses on the broad outcomes of a research project which aimed to analyse and model student teachers' learning in the online components of an initial teacher education course. It begins with discussion of the methodological approach adopted for the case study, which combined conventional data gathering techniques with those which are…

  17. Online Bayesian modeling and prediction of nonlinear systems--Sequential Monte Carlo approach.

    PubMed

    Matsumoto, T

    2007-01-01

    Given time-series data from an unknown target system, one often wants to build a model for the system behind the data and make predictions. If the target system can be assumed to be linear, there are means of modeling and predicting the target system in question. If, however, one cannot assume the system is linear, various linear theories have natural limitations in terms of modeling and predictive capabilities. This paper attempts to construct a model from time-series data and make an online prediction when the linear assumption is not valid. The problem is formulated within a Bayesian framework implemented by the Sequential Monte Carlo method. Online Bayesian learning/prediction requires computation of a posterior distribution in a sequential manner as each datum arrives. The Sequential Monte Carlo method computes the importance weight in order to draw samples from the posterior distribution. The scheme is tested against time-series data from a noisy Rossler system. The test time-series data is the x-coordinate of the trajectory generated by a noisy Roessler system. Attempts are made with regard to online reconstruction of the attractor and online prediction of the time-series data. The proposed algorithm appears to be functional. The algorithm should be tested against real world data.

  18. Using the Jigsaw Model to Facilitate Cooperative Learning in an Online Course

    ERIC Educational Resources Information Center

    Weidman, Rob; Bishop, M. J.

    2009-01-01

    This study examined whether the jigsaw model might be used in an online higher education course to produce the key characteristics of successful cooperative learning: interdependence, individual accountability, development of social skills, and promotive interaction. The authors employed a qualitative case study design to examine a 6-week online…

  19. Mentoring Professors: A Model for Developing Quality Online Instructors and Courses in Higher Education

    ERIC Educational Resources Information Center

    Barczyk, Casimir; Buckenmeyer, Janet; Feldman, Lori

    2010-01-01

    This article presents a four-stage model for mentoring faculty in higher education to deliver high quality online instruction. It provides a timeline that shows the stages of program implementation. Known as the Distance Education Mentoring Program, its major outcomes include certified instructors, student achievement, and the attainment of a…

  20. Phenomenological Study of Business Models Used to Scale Online Enrollment at Institutions of Higher Education

    ERIC Educational Resources Information Center

    Williams, Dana E.

    2012-01-01

    The purpose of this qualitative phenomenological study was to explore factors for selecting a business model for scaling online enrollment by institutions of higher education. The goal was to explore the lived experiences of academic industry experts involved in the selection process. The research question for this study was: What were the lived…

  1. Assessing Readiness for Online Education--Research Models for Identifying Students at Risk

    ERIC Educational Resources Information Center

    Wladis, Claire; Conway, Katherine M.; Hachey, Alyse C.

    2016-01-01

    This study explored the interaction between student characteristics and the online environment in predicting course performance and subsequent college persistence among students in a large urban U.S. university system. Multilevel modeling, propensity score matching, and the KHB decomposition method were used. The most consistent pattern observed…

  2. Using the Community of Inquiry Model to Investigate Students' Knowledge Construction in Asynchronous Online Discussions

    ERIC Educational Resources Information Center

    Liu, Chien-Jen; Yang, Shu Ching

    2014-01-01

    This study used the Community of Inquiry (CoI) model proposed by Garrison to investigate students' level of knowledge construction in asynchronous discussions. The participants included 36 senior students (27 males) majoring in information management. The students attended 18 weeks of an online information ethics course. In this study, four types…

  3. Enhancing Cognitive Presence in Online Case Discussions with Questions Based on the Practical Inquiry Model

    ERIC Educational Resources Information Center

    Sadaf, Ayesha; Olesova, Larisa

    2017-01-01

    The researchers in this study examined the influence of questions designed with the Practical Inquiry Model (PIM), compared with the regular (playground) questions, on students' levels of cognitive presence in online discussions. Students' discussion postings were collected and categorized according to the four levels of cognitive presence:…

  4. Taking the Epistemic Step: Toward a Model of On-Line Access to Conversational Implicatures

    ERIC Educational Resources Information Center

    Breheny, Richard; Ferguson, Heather J.; Katsos, Napoleon

    2013-01-01

    There is a growing body of evidence showing that conversational implicatures are rapidly accessed in incremental utterance interpretation. To date, studies showing incremental access have focussed on implicatures related to linguistic triggers, such as "some" and "or". We discuss three kinds of on-line model that can account for this data. A model…

  5. Analysis of Feedback Processes in Online Group Interaction: A Methodological Model

    ERIC Educational Resources Information Center

    Espasa, Anna; Guasch, Teresa; Alvarez, Ibis M.

    2013-01-01

    The aim of this article is to present a methodological model to analyze students' group interaction to improve their essays in online learning environments, based on asynchronous and written communication. In these environments teacher and student scaffolds for discussion are essential to promote interaction. One of these scaffolds can be the…

  6. A decade of web server updates at the bioinformatics links directory: 2003–2012

    PubMed Central

    Brazas, Michelle D.; Yim, David; Yeung, Winston; Ouellette, B. F. Francis

    2012-01-01

    The 2012 Bioinformatics Links Directory update marks the 10th special Web Server issue from Nucleic Acids Research. Beginning with content from their 2003 publication, the Bioinformatics Links Directory in collaboration with Nucleic Acids Research has compiled and published a comprehensive list of freely accessible, online tools, databases and resource materials for the bioinformatics and life science research communities. The past decade has exhibited significant growth and change in the types of tools, databases and resources being put forth, reflecting both technology changes and the nature of research over that time. With the addition of 90 web server tools and 12 updates from the July 2012 Web Server issue of Nucleic Acids Research, the Bioinformatics Links Directory at http://bioinformatics.ca/links_directory/ now contains an impressive 134 resources, 455 databases and 1205 web server tools, mirroring the continued activity and efforts of our field. PMID:22700703

  7. Online Use of Physically Based Plasticity Models for Steady State Cold Rolling Processes

    NASA Astrophysics Data System (ADS)

    Decroos, Koen; Seefeldt, Marc

    2013-12-01

    A procedure has been developed to incorporate computationally costly physically based crystal plasticity models to calculate texture and anisotropy for steady state forming processes online. When using these models, at every point in the deformed zone, an average and a nonlinear solution procedure for stresses and/or strains in all these grains is required. The online calculation cost is avoided by offline creating a database with texture and anisotropy data for all possible deformation modes of the process. The case studied is a cold rolling process, but can easily be extended to any type of forming process, when the deformation field is known in advance. Textures and anisotropy data are predicted using a viscoplastic self-consistent model, but the method is suitable for any kind of crystal plasticity model. Single crystal plastic parameters, such as the critical resolved shear stress, the single crystal hardening parameters, and the strain-rate sensitivity, have been calibrated based on mechanical tests by means of a direct search simplex algorithm. The online calculated deformation history is compared to the histories stored in the database and the best match is selected. The deformation history is divided in two zones, the one before the neutral point where forward shearing occurs and the one after the neutral point where backward shearing occurs. One online deformation generation and selection procedure requires 0.005 s of CPU time for a database with a division in deformation gradients fine enough to accurately cover all deformations. The method allows calculating yield surfaces at any point in space based on microstructural effects modeled by crystal plasticity, without incremental material updating and necessity to define a kinematic and isotropic hardening, which makes the method suitable for fast models to calculate rolling forces and torques online.

  8. CRONOS: the cross-reference navigation server

    PubMed Central

    Waegele, Brigitte; Dunger-Kaltenbach, Irmtraud; Fobo, Gisela; Montrone, Corinna; Mewes, H.-Werner; Ruepp, Andreas

    2009-01-01

    Summary: Cross-mapping of gene and protein identifiers between different databases is a tedious and time-consuming task. To overcome this, we developed CRONOS, a cross-reference server that contains entries from five mammalian organisms presented by major gene and protein information resources. Sequence similarity analysis of the mapped entries shows that the cross-references are highly accurate. In total, up to 18 different identifier types can be used for identification of cross-references. The quality of the mapping could be improved substantially by exclusion of ambiguous gene and protein names which were manually validated. Organism-specific lists of ambiguous terms, which are valuable for a variety of bioinformatics applications like text mining are available for download. Availability: CRONOS is freely available to non-commercial users at http://mips.gsf.de/genre/proj/cronos/index.html, web services are available at http://mips.gsf.de/CronosWSService/CronosWS?wsdl. Contact: brigitte.waegele@helmholtz-muenchen.de Supplementary information: Supplementary data are available at Bioinformatics online. The online Supplementary Material contains all figures and tables referenced by this article. PMID:19010804

  9. GENIUS: web server to predict local gene networks and key genes for biological functions

    PubMed Central

    Puelma, Tomas; Araus, Viviana; Canales, Javier; Vidal, Elena A.; Cabello, Juan M.; Soto, Alvaro

    2017-01-01

    Abstract Summary: GENIUS is a user-friendly web server that uses a novel machine learning algorithm to infer functional gene networks focused on specific genes and experimental conditions that are relevant to biological functions of interest. These functions may have different levels of complexity, from specific biological processes to complex traits that involve several interacting processes. GENIUS also enriches the network with new genes related to the biological function of interest, with accuracies comparable to highly discriminative Support Vector Machine methods. Availability and Implementation: GENIUS currently supports eight model organisms and is freely available for public use at http://networks.bio.puc.cl/genius. Contact: genius.psbl@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27993775

  10. Cyberdemocracy and Online Politics: A New Model of Interactivity

    ERIC Educational Resources Information Center

    Ferber, Paul; Foltz, Franz; Pugliese, Rudy

    2007-01-01

    Building on McMillan's two-way model of interactivity, this study presents a three-way model of interactive communication, which is used to assess political Web sites' progress toward the ideals of cyberdemocracy and the fostering of public deliberation. Results of a 3-year study of state legislature Web sites, an analysis of the community…

  11. Cyberdemocracy and Online Politics: A New Model of Interactivity

    ERIC Educational Resources Information Center

    Ferber, Paul; Foltz, Franz; Pugliese, Rudy

    2007-01-01

    Building on McMillan's two-way model of interactivity, this study presents a three-way model of interactive communication, which is used to assess political Web sites' progress toward the ideals of cyberdemocracy and the fostering of public deliberation. Results of a 3-year study of state legislature Web sites, an analysis of the community…

  12. The web server of IBM's Bioinformatics and Pattern Discovery group

    PubMed Central

    Huynh, Tien; Rigoutsos, Isidore; Parida, Laxmi; Platt, Daniel; Shibuya, Tetsuo

    2003-01-01

    We herein present and discuss the services and content which are available on the web server of IBM's Bioinformatics and Pattern Discovery group. The server is operational around the clock and provides access to a variety of methods that have been published by the group's members and collaborators. The available tools correspond to applications ranging from the discovery of patterns in streams of events and the computation of multiple sequence alignments, to the discovery of genes in nucleic acid sequences and the interactive annotation of amino acid sequences. Additionally, annotations for more than 70 archaeal, bacterial, eukaryotic and viral genomes are available on-line and can be searched interactively. The tools and code bundles can be accessed beginning at http://cbcsrv.watson.ibm.com/Tspd.html whereas the genomics annotations are available at http://cbcsrv.watson.ibm.com/Annotations/. PMID:12824385

  13. GSDS 2.0: an upgraded gene feature visualization server.

    PubMed

    Hu, Bo; Jin, Jinpu; Guo, An-Yuan; Zhang, He; Luo, Jingchu; Gao, Ge

    2015-04-15

    : Visualizing genes' structure and annotated features helps biologists to investigate their function and evolution intuitively. The Gene Structure Display Server (GSDS) has been widely used by more than 60 000 users since its first publication in 2007. Here, we reported the upgraded GSDS 2.0 with a newly designed interface, supports for more types of annotation features and formats, as well as an integrated visual editor for editing the generated figure. Moreover, a user-specified phylogenetic tree can be added to facilitate further evolutionary analysis. The full source code is also available for downloading. Web server and source code are freely available at http://gsds.cbi.pku.edu.cn. gaog@mail.cbi.pku.edu.cn or gsds@mail.cbi.pku.edu.cn Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

  14. The web server of IBM's Bioinformatics and Pattern Discovery group.

    PubMed

    Huynh, Tien; Rigoutsos, Isidore; Parida, Laxmi; Platt, Daniel; Shibuya, Tetsuo

    2003-07-01

    We herein present and discuss the services and content which are available on the web server of IBM's Bioinformatics and Pattern Discovery group. The server is operational around the clock and provides access to a variety of methods that have been published by the group's members and collaborators. The available tools correspond to applications ranging from the discovery of patterns in streams of events and the computation of multiple sequence alignments, to the discovery of genes in nucleic acid sequences and the interactive annotation of amino acid sequences. Additionally, annotations for more than 70 archaeal, bacterial, eukaryotic and viral genomes are available on-line and can be searched interactively. The tools and code bundles can be accessed beginning at http://cbcsrv.watson.ibm.com/Tspd.html whereas the genomics annotations are available at http://cbcsrv.watson.ibm.com/Annotations/.

  15. Adventures in the evolution of a high-bandwidth network for central servers

    SciTech Connect

    Swartz, K.L.; Cottrell, L.; Dart, M.

    1994-08-01

    In a small network, clients and servers may all be connected to a single Ethernet without significant performance concerns. As the number of clients on a network grows, the necessity of splitting the network into multiple sub-networks, each with a manageable number of clients, becomes clear. Less obvious is what to do with the servers. Group file servers on subnets and multihomed servers offer only partial solutions -- many other types of servers do not lend themselves to a decentralized model, and tend to collect on another, well-connected but overloaded Ethernet. The higher speed of FDDI seems to offer an easy solution, but in practice both expense and interoperability problems render FDDI a poor choice. Ethernet switches appear to permit cheaper and more reliable networking to the servers while providing an aggregate network bandwidth greater than a simple Ethernet. This paper studies the evolution of the server networks at SLAC. Difficulties encountered in the deployment of FDDI are described, as are the tools and techniques used to characterize the traffic patterns on the server network. Performance of Ethernet, FDDI, and switched Ethernet networks is analyzed, as are reliability and maintainability issues for these alternatives. The motivations for re-designing the SLAC general server network to use a switched Ethernet instead of FDDI are described, as are the reasons for choosing FDDI for the farm and firewall networks at SLAC. Guidelines are developed which may help in making this choice for other networks.

  16. Telerobotic control of a mobile coordinated robotic server. M.S. Thesis Annual Technical Report

    NASA Technical Reports Server (NTRS)

    Lee, Gordon

    1993-01-01

    The annual report on telerobotic control of a mobile coordinated robotic server is presented. The goal of this effort is to develop advanced control methods for flexible space manipulator systems. As such, an adaptive fuzzy logic controller was developed in which model structure as well as parameter constraints are not required for compensation. The work builds upon previous work on fuzzy logic controllers. Fuzzy logic controllers have been growing in importance in the field of automatic feedback control. Hardware controllers using fuzzy logic have become available as an alternative to the traditional PID controllers. Software has also been introduced to aid in the development of fuzzy logic rule-bases. The advantages of using fuzzy logic controllers include the ability to merge the experience and intuition of expert operators into the rule-base and that a model of the system is not required to construct the controller. A drawback of the classical fuzzy logic controller, however, is the many parameters needed to be turned off-line prior to application in the closed-loop. In this report, an adaptive fuzzy logic controller is developed requiring no system model or model structure. The rule-base is defined to approximate a state-feedback controller while a second fuzzy logic algorithm varies, on-line, parameters of the defining controller. Results indicate the approach is viable for on-line adaptive control of systems when the model is too complex or uncertain for application of other more classical control techniques.

  17. A decision-making process model of young online shoppers.

    PubMed

    Lin, Chin-Feng; Wang, Hui-Fang

    2008-12-01

    Based on the concepts of brand equity, means-end chain, and Web site trust, this study proposes a novel model called the consumption decision-making process of adolescents (CDMPA) to understand adolescents' Internet consumption habits and behavioral intention toward particular sporting goods. The findings of the CDMPA model can help marketers understand adolescents' consumption preferences and habits for developing effective Internet marketing strategies.

  18. The WRF-Chemistry Air Quality Model: updates and online/offline comparisons

    NASA Astrophysics Data System (ADS)

    Grell, G. A.; Peckham, S. E.; Skamarock, W. C.; McKeen, S. A.

    2005-12-01

    This presentation will first describe the latest updates to the Weather Research and Forecasting (WRF) model as it is coupled to fully online chemistry. This model now includes many atmospheric chemistry routines covering biogenic emissions, deposition, photolysis, chemical mechanisms, and aerosols. Usually the chemistry and aerosol routines are solved in an 'online' or 'fully-coupled' fashion with the meteorological forecast model. In other words, the interaction and transport of meteorological, chemical, and aerosol species are calculated using the same physical parameterizations with no need to interpolate in time and/or space. However, the model can also be run using an offline method. This offline version still uses the same physics parameterization. Time averaged values of the meteorological fields are produced by the meteorological part of the model, and then interpolated in time to feed the chemical transport part of the model. The presentation will cover the evaluation of the WRF/Chem model using a test bed dataset from the summer of 2004. In addition, we will show comparisons of the online simulation with offline simulations using different coupling intervals. The simulations were done with a 12-km horizontal resolution and coupling intervals of 60-, 30-, and 10-min. Averaged surface statistics as well as results from one case will be shown.

  19. Online estimation algorithm for a biaxial ankle kinematic model with configuration dependent joint axes.

    PubMed

    Tsoi, Y H; Xie, S Q

    2011-02-01

    The kinematics of the human ankle is commonly modeled as a biaxial hinge joint model. However, significant variations in axis orientations have been found between different individuals and also between different foot configurations. For ankle rehabilitation robots, information regarding the ankle kinematic parameters can be used to estimate the ankle and subtalar joint displacements. This can in turn be used as auxiliary variables in adaptive control schemes to allow modification of the robot stiffness and damping parameters to reduce the forces applied at stiffer foot configurations. Due to the large variations observed in the ankle kinematic parameters, an online identification algorithm is required to provide estimates of the model parameters. An online parameter estimation routine based on the recursive least-squares (RLS) algorithm was therefore developed in this research. An extension of the conventional biaxial ankle kinematic model, which allows variation in axis orientations with different foot configurations had also been developed and utilized in the estimation algorithm. Simulation results showed that use of the extended model in the online algorithm is effective in capturing the foot orientation of a biaxial ankle model with variable joint axis orientations. Experimental results had also shown that a modified RLS algorithm that penalizes a deviation of model parameters from their nominal values can be used to obtain more realistic parameter estimates while maintaining a level of estimation accuracy comparable to that of the conventional RLS routine.

  20. An adaptive model for vanadium redox flow battery and its application for online peak power estimation

    NASA Astrophysics Data System (ADS)

    Wei, Zhongbao; Meng, Shujuan; Tseng, King Jet; Lim, Tuti Mariana; Soong, Boon Hee; Skyllas-Kazacos, Maria

    2017-03-01

    An accurate battery model is the prerequisite for reliable state estimate of vanadium redox battery (VRB). As the battery model parameters are time varying with operating condition variation and battery aging, the common methods where model parameters are empirical or prescribed offline lacks accuracy and robustness. To address this issue, this paper proposes to use an online adaptive battery model to reproduce the VRB dynamics accurately. The model parameters are online identified with both the recursive least squares (RLS) and the extended Kalman filter (EKF). Performance comparison shows that the RLS is superior with respect to the modeling accuracy, convergence property, and computational complexity. Based on the online identified battery model, an adaptive peak power estimator which incorporates the constraints of voltage limit, SOC limit and design limit of current is proposed to fully exploit the potential of the VRB. Experiments are conducted on a lab-scale VRB system and the proposed peak power estimator is verified with a specifically designed "two-step verification" method. It is shown that different constraints dominate the allowable peak power at different stages of cycling. The influence of prediction time horizon selection on the peak power is also analyzed.

  1. Modeling the cooperative and competitive contagions in online social networks

    NASA Astrophysics Data System (ADS)

    Zhuang, Yun-Bei; Chen, J. J.; Li, Zhi-hong

    2017-10-01

    The wide adoption of social media has increased the interaction among different pieces of information, and this interaction includes cooperation and competition for our finite attention. While previous research focus on fully competition, this paper extends the interaction to be both ;cooperation; and ;competition;, by employing an IS1S2 R model. To explore how two different pieces of information interact with each other, the IS1S2 R model splits the agents into four parts-(Ignorant-Spreader I-Spreader II-Stifler), based on SIR epidemic spreading model. Using real data from Weibo.com, a social network site similar to Twitter, we find some parameters, like decaying rates, can both influence the cooperative diffusion process and the competitive process, while other parameters, like infectious rates only have influence on the competitive diffusion process. Besides, the parameters' effect are more significant in the competitive diffusion than in the cooperative diffusion.

  2. Hybrid metrology implementation: server approach

    NASA Astrophysics Data System (ADS)

    Osorio, Carmen; Timoney, Padraig; Vaid, Alok; Elia, Alex; Kang, Charles; Bozdog, Cornel; Yellai, Naren; Grubner, Eyal; Ikegami, Toru; Ikeno, Masahiko

    2015-03-01

    Hybrid metrology (HM) is the practice of combining measurements from multiple toolset types in order to enable or improve metrology for advanced structures. HM is implemented in two phases: Phase-1 includes readiness of the infrastructure to transfer processed data from the first toolset to the second. Phase-2 infrastructure allows simultaneous transfer and optimization of raw data between toolsets such as spectra, images, traces - co-optimization. We discuss the extension of Phase-1 to include direct high-bandwidth communication between toolsets using a hybrid server, enabling seamless fab deployment and further laying the groundwork for Phase-2 high volume manufacturing (HVM) implementation. An example of the communication protocol shows the information that can be used by the hybrid server, differentiating its capabilities from that of a host-based approach. We demonstrate qualification and production implementation of the hybrid server approach using CD-SEM and OCD toolsets for complex 20nm and 14nm applications. Finally we discuss the roadmap for Phase-2 HM implementation through use of the hybrid server.

  3. SciServer Compute brings Analysis to Big Data in the Cloud

    NASA Astrophysics Data System (ADS)

    Raddick, Jordan; Medvedev, Dmitry; Lemson, Gerard; Souter, Barbara

    2016-06-01

    SciServer Compute uses Jupyter Notebooks running within server-side Docker containers attached to big data collections to bring advanced analysis to big data "in the cloud." SciServer Compute is a component in the SciServer Big-Data ecosystem under development at JHU, which will provide a stable, reproducible, sharable virtual research environment.SciServer builds on the popular CasJobs and SkyServer systems that made the Sloan Digital Sky Survey (SDSS) archive one of the most-used astronomical instruments. SciServer extends those systems with server-side computational capabilities and very large scratch storage space, and further extends their functions to a range of other scientific disciplines.Although big datasets like SDSS have revolutionized astronomy research, for further analysis, users are still restricted to downloading the selected data sets locally - but increasing data sizes make this local approach impractical. Instead, researchers need online tools that are co-located with data in a virtual research environment, enabling them to bring their analysis to the data.SciServer supports this using the popular Jupyter notebooks, which allow users to write their own Python and R scripts and execute them on the server with the data (extensions to Matlab and other languages are planned). We have written special-purpose libraries that enable querying the databases and other persistent datasets. Intermediate results can be stored in large scratch space (hundreds of TBs) and analyzed directly from within Python or R with state-of-the-art visualization and machine learning libraries. Users can store science-ready results in their permanent allocation on SciDrive, a Dropbox-like system for sharing and publishing files. Communication between the various components of the SciServer system is managed through SciServer‘s new Single Sign-on Portal.We have created a number of demos to illustrate the capabilities of SciServer Compute, including Python and R scripts

  4. Architectural Improvements and New Processing Tools for the Open XAL Online Model

    SciTech Connect

    Allen, Christopher K; Pelaia II, Tom; Freed, Jonathan M

    2015-01-01

    The online model is the component of Open XAL providing accelerator modeling, simulation, and dynamic synchronization to live hardware. Significant architectural changes and feature additions have been recently made in two separate areas: 1) the managing and processing of simulation data, and 2) the modeling of RF cavities. Simulation data and data processing have been completely decoupled. A single class manages all simulation data while standard tools were developed for processing the simulation results. RF accelerating cavities are now modeled as composite structures where parameter and dynamics computations are distributed. The beam and hardware models both maintain their relative phase information, which allows for dynamic phase slip and elapsed time computation.

  5. Exploring the Earth System through online interactive models

    NASA Astrophysics Data System (ADS)

    Coogan, L. A.

    2013-12-01

    Upper level Earth Science students commonly have a strong background of mathematical training from Math courses, however their ability to use mathematical models to solve Earth Science problems is commonly limited. Their difficulty comes, in part, because of the nature of the subject matter. There is a large body of background ';conceptual' and ';observational' understanding and knowledge required in the Earth Sciences before in-depth quantification becomes useful. For example, it is difficult to answer questions about geological processes until you can identify minerals and rocks and understand the general geodynamic implications of their associations. However, science is fundamentally quantitative. To become scientists students have to translate their conceptual understanding into quantifiable models. Thus, it is desirable for students to become comfortable with using mathematical models to test hypotheses. With the aim of helping to bridging the gap between conceptual understanding and quantification I have started to build an interactive teaching website based around quantitative models of Earth System processes. The site is aimed at upper-level undergraduate students and spans a range of topics that will continue to grow as time allows. The mathematical models are all built for the students, allowing them to spend their time thinking about how the ';model world' changes in response to their manipulation of the input variables. The web site is divided into broad topics or chapters (Background, Solid Earth, Ocean and Atmosphere, Earth history) and within each chapter there are different subtopic (e.g. Solid Earth: Core, Mantle, Crust) and in each of these individual webpages. Each webpage, or topic, starts with an introduction to the topic, followed by an interactive model that the students can use sliders to control the input to and watch how the results change. This interaction between student and model is guided by a series of multiple choice questions that

  6. Towards a Social Networks Model for Online Learning & Performance

    ERIC Educational Resources Information Center

    Chung, Kon Shing Kenneth; Paredes, Walter Christian

    2015-01-01

    In this study, we develop a theoretical model to investigate the association between social network properties, "content richness" (CR) in academic learning discourse, and performance. CR is the extent to which one contributes content that is meaningful, insightful and constructive to aid learning and by social network properties we…

  7. Peer Assessment with Online Tools to Improve Student Modeling

    ERIC Educational Resources Information Center

    Atkins, Leslie J.

    2012-01-01

    Introductory physics courses often require students to develop precise models of phenomena and represent these with diagrams, including free-body diagrams, light-ray diagrams, and maps of field lines. Instructors expect that students will adopt a certain rigor and precision when constructing these diagrams, but we want that rigor and precision to…

  8. Understanding the Effectiveness of Online Peer Assessment: A Path Model

    ERIC Educational Resources Information Center

    Lu, Jingyan; Zhang, Zhidong

    2012-01-01

    Peer assessment has been implemented in schools as both a learning tool and an assessment tool. Earlier studies have explored the effectiveness of peer assessment from different perspectives, such as domain knowledge and skills, peer assessment skills, and attitude changes. However, there is no holistic model describing the effects of cognitive…

  9. Towards a Social Networks Model for Online Learning & Performance

    ERIC Educational Resources Information Center

    Chung, Kon Shing Kenneth; Paredes, Walter Christian

    2015-01-01

    In this study, we develop a theoretical model to investigate the association between social network properties, "content richness" (CR) in academic learning discourse, and performance. CR is the extent to which one contributes content that is meaningful, insightful and constructive to aid learning and by social network properties we…

  10. Understanding the Effectiveness of Online Peer Assessment: A Path Model

    ERIC Educational Resources Information Center

    Lu, Jingyan; Zhang, Zhidong

    2012-01-01

    Peer assessment has been implemented in schools as both a learning tool and an assessment tool. Earlier studies have explored the effectiveness of peer assessment from different perspectives, such as domain knowledge and skills, peer assessment skills, and attitude changes. However, there is no holistic model describing the effects of cognitive…

  11. Promoting Continuous Quality Improvement in Online Teaching: The META Model

    ERIC Educational Resources Information Center

    Dittmar, Eileen; McCracken, Holly

    2012-01-01

    Experienced e-learning faculty members share strategies for implementing a comprehensive postsecondary faculty development program essential to continuous improvement of instructional skills. The high-impact META Model (centered around Mentoring, Engagement, Technology, and Assessment) promotes information sharing and content creation, and fosters…

  12. The challenge of integrating new online education packages into existing curricula: a new model.

    PubMed

    Grant, Janet; Owen, Heather; Sandars, John; Walsh, Kieran; Richardson, Judith; Rutherford, Alaster; Siddiqi, Kamran; Ibison, Judith; Maxted, Mairead

    2011-01-01

    In 2009, The National Institute for Health and Clinical Excellence (NICE) developed an undergraduate online learning package on the practical application of evidence-based medicine with the intention that it would be integrated into existing medical curricula. Complementary methodologies were used to yield a diversity of quantitative and qualitative data on how the online learning package was integrated. The modules of the online learning package received an overall positive reaction from the users but uptake of the modules was lower than expected. Even though some curriculum integration occurred, several students were unaware that the package existed, some lacked the time to use the package and others would have preferred to have had the package earlier in their course. A new model for the effective integration of online education packages into existing undergraduate medical curricula is proposed, especially when developed by external organisations. This new model should enable educationalists to better reveal and overcome the contextual and process challenges, barriers and solutions to implementing effective flexible learning approaches. When introducing new learning resources into a curriculum, many factors are important, especially the learners' perceived needs and how these vary at different stages of their course.

  13. Scalable Topic Modeling: Online Learning, Diagnostics, and Recommendation

    DTIC Science & Technology

    2017-03-01

    group has significantly pushed the needle on modern Bayesian machine learning. We have developed new and impactful algorithms, stretched its scope to...36) 14534–14539, 2013. 5. M. Hoffman, D. Blei, C. Wang, and J. Paisley. Stochastic variational inference. Journal of Machine Learning Research, 14:1303...1347, 2013. 6. C. Wang and D. Blei. Variational inference in nonconjugate models. Journal of Machine Learning Research, 14:1005–1031, 2013. 2 7. P

  14. Autonomous Coordination and Online Motion Modeling for Mobile Robots

    DTIC Science & Technology

    2007-09-01

    number of robots. The second goal of this work is to demonstrate a method by which a robot can automatically determine how it is moving...The second goal of this work is to demonstrate a method by which a robot can automatically determine how it is moving. Experiments demonstrate the...to introduce a method for automatically learning a robot’s motion model. The algorithm will be employed on real mobile robots so as to ensure the

  15. On-line simulations of models for backward masking.

    PubMed

    Francis, Gregory

    2003-11-01

    Five simulations of quantitative models of visual backward masking are available on the Internet at http://www.psych.purdue.edu/-gfrancis/Publications/BackwardMasking/. The simulations can be run in a Web browser that supports the Java programming language. This article describes the motivation for making the simulations available and gives a brief introduction as to how the simulations are used. The source code is available on the Web page, and this article describes how the code is organized.

  16. Peer Assessment with Online Tools to Improve Student Modeling

    NASA Astrophysics Data System (ADS)

    Atkins, Leslie J.

    2012-11-01

    Introductory physics courses often require students to develop precise models of phenomena and represent these with diagrams, including free-body diagrams, light-ray diagrams, and maps of field lines. Instructors expect that students will adopt a certain rigor and precision when constructing these diagrams, but we want that rigor and precision to be an aid to sense-making rather than meeting seemingly arbitrary requirements set by the instructor. By giving students the authority to develop their own models and establish requirements for their diagrams, the sense that these are arbitrary requirements diminishes and students are more likely to see modeling as a sense-making activity. The practice of peer assessment can help students take ownership; however, it can be difficult for instructors to manage. Furthermore, it is not without risk: students can be reluctant to critique their peers, they may view this as the job of the instructor, and there is no guarantee that students will employ greater rigor and precision as a result of peer assessment. In this article, we describe one approach for peer assessment that can establish norms for diagrams in a way that is student driven, where students retain agency and authority in assessing and improving their work. We show that such an approach does indeed improve students' diagrams and abilities to assess their own work, without sacrificing students' authority and agency.

  17. Robust object tracking via online dynamic spatial bias appearance models.

    PubMed

    Chen, Datong; Yang, Jie

    2007-12-01

    This paper presents a robust object tracking method via a spatial bias appearance model learned dynamically in video. Motivated by the attention shifting among local regions of a human vision system during object tracking, we propose to partition an object into regions with different confidences and track the object using a dynamic spatial bias appearance model (DSBAM) estimated from region confidences. The confidence of a region is estimated to re ect the discriminative power of the region in a feature space, and the probability of occlusion. We propose a novel hierarchical Monte Carlo (HAMC) algorithm to learn region confidences dynamically in every frame. The algorithm consists of two levels of Monte Carlo processes implemented using two particle filtering procedures at each level and can efficiently extract high confidence regions through video frames by exploiting the temporal consistency of region confidences. A dynamic spatial bias map is then generated from the high confidence regions, and is employed to adapt the appearance model of the object and to guide a tracking algorithm in searching for correspondences in adjacent frames of video images. We demonstrate feasibility of the proposed method in video surveillance applications. The proposed method can be combined with many other existing tracking systems to enhance the robustness of these systems.

  18. An epidemic model of rumor diffusion in online social networks

    NASA Astrophysics Data System (ADS)

    Cheng, Jun-Jun; Liu, Yun; Shen, Bo; Yuan, Wei-Guo

    2013-01-01

    So far, in some standard rumor spreading models, the transition probability from ignorants to spreaders is always treated as a constant. However, from a practical perspective, the case that individual whether or not be infected by the neighbor spreader greatly depends on the trustiness of ties between them. In order to solve this problem, we introduce a stochastic epidemic model of the rumor diffusion, in which the infectious probability is defined as a function of the strength of ties. Moreover, we investigate numerically the behavior of the model on a real scale-free social site with the exponent γ = 2.2. We verify that the strength of ties plays a critical role in the rumor diffusion process. Specially, selecting weak ties preferentially cannot make rumor spread faster and wider, but the efficiency of diffusion will be greatly affected after removing them. Another significant finding is that the maximum number of spreaders max( S) is very sensitive to the immune probability μ and the decay probability v. We show that a smaller μ or v leads to a larger spreading of the rumor, and their relationships can be described as the function ln(max( S)) = Av + B, in which the intercept B and the slope A can be fitted perfectly as power-law functions of μ. Our findings may offer some useful insights, helping guide the application in practice and reduce the damage brought by the rumor.

  19. (PS)2: protein structure prediction server

    PubMed Central

    Chen, Chih-Chieh; Hwang, Jenn-Kang; Yang, Jinn-Moon

    2006-01-01

    Protein structure prediction provides valuable insights into function, and comparative modeling is one of the most reliable methods to predict 3D structures directly from amino acid sequences. However, critical problems arise during the selection of the correct templates and the alignment of query sequences therewith. We have developed an automatic protein structure prediction server, (PS)2, which uses an effective consensus strategy both in template selection, which combines PSI-BLAST and IMPALA, and target–template alignment integrating PSI-BLAST, IMPALA and T-Coffee. (PS)2 was evaluated for 47 comparative modeling targets in CASP6 (Critical Assessment of Techniques for Protein Structure Prediction). For the benchmark dataset, the predictive performance of (PS)2, based on the mean GTD_TS score, was superior to 10 other automatic servers. Our method is based solely on the consensus sequence and thus is considerably faster than other methods that rely on the additional structural consensus of templates. Our results show that (PS)2, coupled with suitable consensus strategies and a new similarity score, can significantly improve structure prediction. Our approach should be useful in structure prediction and modeling. The (PS)2 is available through the website at . PMID:16844981

  20. Online motor fault detection and diagnosis using a hybrid FMM-CART model.

    PubMed

    Seera, Manjeevan; Lim, Chee Peng

    2014-04-01

    In this brief, a hybrid model combining the fuzzy min-max (FMM) neural network and the classification and regression tree (CART) for online motor detection and diagnosis tasks is described. The hybrid model, known as FMM-CART, exploits the advantages of both FMM and CART for undertaking data classification and rule extraction problems. To evaluate the applicability of the proposed FMM-CART model, an evaluation with a benchmark data set pertaining to electrical motor bearing faults is first conducted. The results obtained are equivalent to those reported in the literature. Then, a laboratory experiment for detecting and diagnosing eccentricity faults in an induction motor is performed. In addition to producing accurate results, useful rules in the form of a decision tree are extracted to provide explanation and justification for the predictions from FMM-CART. The experimental outcome positively shows the potential of FMM-CART in undertaking online motor fault detection and diagnosis tasks.

  1. Evaluation of surface ozone simulated by the WRF/CMAQ online modelling system

    NASA Astrophysics Data System (ADS)

    Marougianni, Garyfalia; Katragkou, Eleni; Giannaros, Theodoros; Poupkou, Anastasia; Melas, Dimitris; Zanis, Prodromos; Feidas, Haralambos

    2013-04-01

    In this work we evaluate the online model WRF/CMAQ with respect to surface ozone and compare its performance with an off-line modelling system (WRF/CAMx) that has been operationally used by Aristotle University of Thessaloniki (AUTH) for chemical weather forecasting in the Mediterranean. The online model consists of the mesoscale meteorological model WRF3.3 and the air quality model CMAQ5.0.1 which are coupled in every time-step. The modelling domain covers Europe with a resolution of 30 Km (identical projection for meteorological and chemistry simulations to avoid interpolation errors) and CMAQ has 17 vertical layers extending up to 15 Km. Anthropogenic emissions are prepared according to the SNAP nomenclature and the biogenic emissions are provided by the Natural Emission Model (NEMO) developed by AUTH. A 2-month simulation is performed by WRF/CMAQ covering the time period of June-July 2010. Average monthly concentration values obtained from the MACCII service (IFS-Mozart) are used as chemical boundary conditions for the simulations. For the WRF simulations boundary conditions are provided by the ECMWF. The same boundaries, chemical mechanism (CBV), emissions and model set up is used in the off-line WRF/CAMx in order to allow a more direct comparison of model results. To evaluate the performance of the WRF/CMAQ online model, simulated ozone concentrations are compared against near surface ozone measurements from the EMEP network. Τhe model has been validated with the climatic observational database that has been compiled in the framework of the GEOCLIMA project (http://www.geoclima.eu/). In the evaluation analysis only those stations that fulfill the criterion of 75% data availability for near surface ozone are used. Various statistical metrics are used for the model evaluation, including correlation coefficient (R), normalized standard deviation (NSD) and modified normalized mean bias (MNMB). The final aim is to investigate whether the state-of-the-art WRF

  2. Online and offline peer led models against bullying and cyberbullying.

    PubMed

    Palladino, Benedetta Emanuela; Nocentini, Annalaura; Menesini, Ersilia

    2012-11-01

    The aim of the present study is to describe and evaluate an ongoing peer-led model against bullying and cyberbullying carried out with Italian adolescents. The evaluation of the project was made through an experimental design consisting of a pre-test and a post-test. Participants in the study were 375 adolescents (20.3% males), enrolled in 9th to 13th grades. The experimental group involved 231 students with 42 peer educators, and the control group involved 144 students. Results showed a significant decrease in the experimental group as compared to the control group for all the variables except for cyberbullying. Besides, in the experimental group we found a significant increase in adaptive coping strategies like problem solving and a significant decrease in maladaptive coping strategies like avoidance: these changes mediate the changes in the behavioural variables. In particular, the decrease in avoidance predicts the decrease in victimization and cybervictimization for peer educators and for the other students in the experimental classes whereas the increase in problem solving predicts the decrease in cyberbullying only in the peer educators group. Results are discussed following recent reviews on evidence based efficacy of peer led models.

  3. Mathematical defense method of networked servers with controlled remote backups

    NASA Astrophysics Data System (ADS)

    Kim, Song-Kyoo

    2006-05-01

    The networked server defense model is focused on reliability and availability in security respects. The (remote) backup servers are hooked up by VPN (Virtual Private Network) with high-speed optical network and replace broken main severs immediately. The networked server can be represent as "machines" and then the system deals with main unreliable, spare, and auxiliary spare machine. During vacation periods, when the system performs a mandatory routine maintenance, auxiliary machines are being used for back-ups; the information on the system is naturally delayed. Analog of the N-policy to restrict the usage of auxiliary machines to some reasonable quantity. The results are demonstrated in the network architecture by using the stochastic optimization techniques.

  4. LassoProt: server to analyze biopolymers with lassos.

    PubMed

    Dabrowski-Tumanski, Pawel; Niemyska, Wanda; Pasznik, Pawel; Sulkowska, Joanna I

    2016-07-08

    The LassoProt server, http://lassoprot.cent.uw.edu.pl/, enables analysis of biopolymers with entangled configurations called lassos. The server offers various ways of visualizing lasso configurations, as well as their time trajectories, with all the results and plots downloadable. Broad spectrum of applications makes LassoProt a useful tool for biologists, biophysicists, chemists, polymer physicists and mathematicians. The server and our methods have been validated on the whole PDB, and the results constitute the database of proteins with complex lassos, supported with basic biological data. This database can serve as a source of information about protein geometry and entanglement-function correlations, as a reference set in protein modeling, and for many other purposes. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Server-Controlled Identity-Based Authenticated Key Exchange

    NASA Astrophysics Data System (ADS)

    Guo, Hua; Mu, Yi; Zhang, Xiyong; Li, Zhoujun

    We present a threshold identity-based authenticated key exchange protocol that can be applied to an authenticated server-controlled gateway-user key exchange. The objective is to allow a user and a gateway to establish a shared session key with the permission of the back-end servers, while the back-end servers cannot obtain any information about the established session key. Our protocol has potential applications in strong access control of confidential resources. In particular, our protocol possesses the semantic security and demonstrates several highly-desirable security properties such as key privacy and transparency. We prove the security of the protocol based on the Bilinear Diffie-Hellman assumption in the random oracle model.

  6. LassoProt: server to analyze biopolymers with lassos

    PubMed Central

    Dabrowski-Tumanski, Pawel; Niemyska, Wanda; Pasznik, Pawel; Sulkowska, Joanna I.

    2016-01-01

    The LassoProt server, http://lassoprot.cent.uw.edu.pl/, enables analysis of biopolymers with entangled configurations called lassos. The server offers various ways of visualizing lasso configurations, as well as their time trajectories, with all the results and plots downloadable. Broad spectrum of applications makes LassoProt a useful tool for biologists, biophysicists, chemists, polymer physicists and mathematicians. The server and our methods have been validated on the whole PDB, and the results constitute the database of proteins with complex lassos, supported with basic biological data. This database can serve as a source of information about protein geometry and entanglement-function correlations, as a reference set in protein modeling, and for many other purposes. PMID:27131383

  7. BION web server: predicting non-specifically bound surface ions.

    PubMed

    Petukh, Marharyta; Kimmet, Taylor; Alexov, Emil

    2013-03-15

    Ions are essential component of the cell and frequently are found bound to various macromolecules, in particular to proteins. A binding of an ion to a protein greatly affects protein's biophysical characteristics and needs to be taken into account in any modeling approach. However, ion's bounded positions cannot be easily revealed experimentally, especially if they are loosely bound to macromolecular surface. Here, we report a web server, the BION web server, which addresses the demand for tools of predicting surface bound ions, for which specific interactions are not crucial; thus, they are difficult to predict. The BION is easy to use web server that requires only coordinate file to be inputted, and the user is provided with various, but easy to navigate, options. The coordinate file with predicted bound ions is displayed on the output and is available for download.

  8. Web server for priority ordered multimedia services

    NASA Astrophysics Data System (ADS)

    Celenk, Mehmet; Godavari, Rakesh K.; Vetnes, Vermund

    2001-10-01

    In this work, our aim is to provide finer priority levels in the design of a general-purpose Web multimedia server with provisions of the CM services. The type of services provided include reading/writing a web page, downloading/uploading an audio/video stream, navigating the Web through browsing, and interactive video teleconferencing. The selected priority encoding levels for such operations follow the order of admin read/write, hot page CM and Web multicasting, CM read, Web read, CM write and Web write. Hot pages are the most requested CM streams (e.g., the newest movies, video clips, and HDTV channels) and Web pages (e.g., portal pages of the commercial Internet search engines). Maintaining a list of these hot Web pages and CM streams in a content addressable buffer enables a server to multicast hot streams with lower latency and higher system throughput. Cold Web pages and CM streams are treated as regular Web and CM requests. Interactive CM operations such as pause (P), resume (R), fast-forward (FF), and rewind (RW) have to be executed without allocation of extra resources. The proposed multimedia server model is a part of the distributed network with load balancing schedulers. The SM is connected to an integrated disk scheduler (IDS), which supervises an allocated disk manager. The IDS follows the same priority handling as the SM, and implements a SCAN disk-scheduling method for an improved disk access and a higher throughput. Different disks are used for the Web and CM services in order to meet the QoS requirements of CM services. The IDS ouput is forwarded to an Integrated Transmission Scheduler (ITS). The ITS creates a priority ordered buffering of the retrieved Web pages and CM data streams that are fed into an auto regressive moving average (ARMA) based traffic shaping circuitry before being transmitted through the network.

  9. Constructs of Student-Centered Online Learning on Learning Satisfaction of a Diverse Online Student Body: A Structural Equation Modeling Approach

    ERIC Educational Resources Information Center

    Ke, Fengfeng; Kwak, Dean

    2013-01-01

    The present study investigated the relationships between constructs of web-based student-centered learning and the learning satisfaction of a diverse online student body. Hypotheses on the constructs of student-centered learning were tested using structural equation modeling. The results indicated that five key constructs of student-centered…

  10. Using Structural Equation Modeling to Validate Online Game Players' Motivations Relative to Self-Concept and Life Adaptation

    ERIC Educational Resources Information Center

    Yang, Shu Ching; Huang, Chiao Ling

    2013-01-01

    This study aimed to validate a systematic instrument to measure online players' motivations for playing online games (MPOG) and examine how the interplay of differential motivations impacts young gamers' self-concept and life adaptation. Confirmatory factor analysis determined that a hierarchical model with a two-factor structure of…

  11. Using Structural Equation Modeling to Validate Online Game Players' Motivations Relative to Self-Concept and Life Adaptation

    ERIC Educational Resources Information Center

    Yang, Shu Ching; Huang, Chiao Ling

    2013-01-01

    This study aimed to validate a systematic instrument to measure online players' motivations for playing online games (MPOG) and examine how the interplay of differential motivations impacts young gamers' self-concept and life adaptation. Confirmatory factor analysis determined that a hierarchical model with a two-factor structure of…

  12. Faculty Perceptions about Teaching Online: Exploring the Literature Using the Technology Acceptance Model as an Organizing Framework

    ERIC Educational Resources Information Center

    Wingo, Nancy Pope; Ivankova, Nataliya V.; Moss, Jacqueline A.

    2017-01-01

    Academic leaders can better implement institutional strategic plans to promote online programs if they understand faculty perceptions about teaching online. An extended version of a model for technology acceptance, or TAM2 (Venkatesh & Davis, 2000), provided a framework for surveying and organizing the research literature about factors that…

  13. When Disney Meets the Research Park: Metaphors and Models for Engineering an Online Learning Community of Tomorrow

    ERIC Educational Resources Information Center

    Chenail, Ronald J.

    2004-01-01

    It is suggested that educators look to an environment in which qualitative research can be learned in more flexible and creative ways--an online learning community known as the Research Park Online (RPO). This model, based upon Walt Disney's 1966 plan for his "Experimental Prototype Community of Tomorrow" (EPCOT) and university cooperative…

  14. When Disney Meets the Research Park: Metaphors and Models for Engineering an Online Learning Community of Tomorrow

    ERIC Educational Resources Information Center

    Chenail, Ronald J.

    2004-01-01

    It is suggested that educators look to an environment in which qualitative research can be learned in more flexible and creative ways--an online learning community known as the Research Park Online (RPO). This model, based upon Walt Disney's 1966 plan for his "Experimental Prototype Community of Tomorrow" (EPCOT) and university cooperative…

  15. Evaluation of Major Online Diabetes Risk Calculators and Computerized Predictive Models

    PubMed Central

    Stiglic, Gregor; Pajnkihar, Majda

    2015-01-01

    Classical paper-and-pencil based risk assessment questionnaires are often accompanied by the online versions of the questionnaire to reach a wider population. This study focuses on the loss, especially in risk estimation performance, that can be inflicted by direct transformation from the paper to online versions of risk estimation calculators by ignoring the possibilities of more complex and accurate calculations that can be performed using the online calculators. We empirically compare the risk estimation performance between four major diabetes risk calculators and two, more advanced, predictive models. National Health and Nutrition Examination Survey (NHANES) data from 1999–2012 was used to evaluate the performance of detecting diabetes and pre-diabetes. American Diabetes Association risk test achieved the best predictive performance in category of classical paper-and-pencil based tests with an Area Under the ROC Curve (AUC) of 0.699 for undiagnosed diabetes (0.662 for pre-diabetes) and 47% (47% for pre-diabetes) persons selected for screening. Our results demonstrate a significant difference in performance with additional benefits for a lower number of persons selected for screening when statistical methods are used. The best AUC overall was obtained in diabetes risk prediction using logistic regression with AUC of 0.775 (0.734) and an average 34% (48%) persons selected for screening. However, generalized boosted regression models might be a better option from the economical point of view as the number of selected persons for screening of 30% (47%) lies significantly lower for diabetes risk assessment in comparison to logistic regression (p < 0.001), with a significantly higher AUC (p < 0.001) of 0.774 (0.740) for the pre-diabetes group. Our results demonstrate a serious lack of predictive performance in four major online diabetes risk calculators. Therefore, one should take great care and consider optimizing the online versions of questionnaires that were

  16. A low-order coupled chemistry meteorology model for testing online and offline data assimilation schemes

    NASA Astrophysics Data System (ADS)

    Haussaire, J.-M.; Bocquet, M.

    2015-08-01

    Bocquet and Sakov (2013) have introduced a low-order model based on the coupling of the chaotic Lorenz-95 model which simulates winds along a mid-latitude circle, with the transport of a tracer species advected by this zonal wind field. This model, named L95-T, can serve as a playground for testing data assimilation schemes with an online model. Here, the tracer part of the model is extended to a reduced photochemistry module. This coupled chemistry meteorology model (CCMM), the L95-GRS model, mimics continental and transcontinental transport and the photochemistry of ozone, volatile organic compounds and nitrogen oxides. Its numerical implementation is described. The model is shown to reproduce the major physical and chemical processes being considered. L95-T and L95-GRS are specifically designed and useful for testing advanced data assimilation schemes, such as the iterative ensemble Kalman smoother (IEnKS) which combines the best of ensemble and variational methods. These models provide useful insights prior to the implementation of data assimilation methods on larger models. We illustrate their use with data assimilation schemes on preliminary, yet instructive numerical experiments. In particular, online and offline data assimilation strategies can be conveniently tested and discussed with this low-order CCMM. The impact of observed chemical species concentrations on the wind field can be quantitatively estimated. The impacts of the wind chaotic dynamics and of the chemical species non-chaotic but highly nonlinear dynamics on the data assimilation strategies are illustrated.

  17. IIR filtering based adaptive active vibration control methodology with online secondary path modeling using PZT actuators

    NASA Astrophysics Data System (ADS)

    Boz, Utku; Basdogan, Ipek

    2015-12-01

    Structural vibrations is a major cause for noise problems, discomfort and mechanical failures in aerospace, automotive and marine systems, which are mainly composed of plate-like structures. In order to reduce structural vibrations on these structures, active vibration control (AVC) is an effective approach. Adaptive filtering methodologies are preferred in AVC due to their ability to adjust themselves for varying dynamics of the structure during the operation. The filtered-X LMS (FXLMS) algorithm is a simple adaptive filtering algorithm widely implemented in active control applications. Proper implementation of FXLMS requires availability of a reference signal to mimic the disturbance and model of the dynamics between the control actuator and the error sensor, namely the secondary path. However, the controller output could interfere with the reference signal and the secondary path dynamics may change during the operation. This interference problem can be resolved by using an infinite impulse response (IIR) filter which considers feedback of the one or more previous control signals to the controller output and the changing secondary path dynamics can be updated using an online modeling technique. In this paper, IIR filtering based filtered-U LMS (FULMS) controller is combined with online secondary path modeling algorithm to suppress the vibrations of a plate-like structure. The results are validated through numerical and experimental studies. The results show that the FULMS with online secondary path modeling approach has more vibration rejection capabilities with higher convergence rate than the FXLMS counterpart.

  18. Modelling unsupervised online-learning of artificial grammars: linking implicit and statistical learning.

    PubMed

    Rohrmeier, Martin A; Cross, Ian

    2014-07-01

    Humans rapidly learn complex structures in various domains. Findings of above-chance performance of some untrained control groups in artificial grammar learning studies raise questions about the extent to which learning can occur in an untrained, unsupervised testing situation with both correct and incorrect structures. The plausibility of unsupervised online-learning effects was modelled with n-gram, chunking and simple recurrent network models. A novel evaluation framework was applied, which alternates forced binary grammaticality judgments and subsequent learning of the same stimulus. Our results indicate a strong online learning effect for n-gram and chunking models and a weaker effect for simple recurrent network models. Such findings suggest that online learning is a plausible effect of statistical chunk learning that is possible when ungrammatical sequences contain a large proportion of grammatical chunks. Such common effects of continuous statistical learning may underlie statistical and implicit learning paradigms and raise implications for study design and testing methodologies. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Opportunities for the Mashup of Heterogenous Data Server via Semantic Web Technology

    NASA Astrophysics Data System (ADS)

    Ritschel, Bernd; Seelus, Christoph; Neher, Günther; Iyemori, Toshihiko; Koyama, Yukinobu; Yatagai, Akiyo; Murayama, Yasuhiro; King, Todd; Hughes, John; Fung, Shing; Galkin, Ivan; Hapgood, Michael; Belehaki, Anna

    2015-04-01

    Opportunities for the Mashup of Heterogenous Data Server via Semantic Web Technology European Union ESPAS, Japanese IUGONET and GFZ ISDC data server are developed for the ingestion, archiving and distributing of geo and space science domain data. Main parts of the data -managed by the mentioned data server- are related to near earth-space and geomagnetic field data. A smart mashup of the data server would allow a seamless browse and access to data and related context information. However the achievement of a high level of interoperability is a challenge because the data server are based on different data models and software frameworks. This paper is focused on the latest experiments and results for the mashup of the data server using the semantic Web approach. Besides the mashup of domain and terminological ontologies, especially the options to connect data managed by relational databases using D2R server and SPARQL technology will be addressed. A successful realization of the data server mashup will not only have a positive impact to the data users of the specific scientific domain but also to related projects, such as e.g. the development of a new interoperable version of NASA's Planetary Data System (PDS) or ICUS's World Data System alliance. ESPAS data server: https://www.espas-fp7.eu/portal/ IUGONET data server: http://search.iugonet.org/iugonet/ GFZ ISDC data server (semantic Web based prototype): http://rz-vm30.gfz-potsdam.de/drupal-7.9/ NASA PDS: http://pds.nasa.gov ICSU-WDS: https://www.icsu-wds.org

  20. Online self-management in rheumatoid arthritis: a patient-centered model application.

    PubMed

    Smarr, Karen L; Musser, Dale R; Shigaki, Cheryl L; Johnson, Rebecca; Hanson, Kathleen Donovan; Siva, Chokkalingam

    2011-03-01

    The aim of this study was to describe the online transformation of an empirically validated, clinic-based, self-management (SM) program for rheumatoid arthritis. A cognitive-behavioral framework served as the theoretical basis for the intervention. As with the clinic-based approach, the psychoeducational program included educational modules, weekly homework assignments, and self-evaluation. The dynamic online environment included secure communication tools to support a virtual community for the participants to garner peer support. In addition to peer support, weekly follow-up support was provided by a trained clinician via telephone. We describe the process and structure of the online self-management (OSM) intervention. Administrative issues including clinical monitoring and management, data collection, and security safeguards are considered. Utilization and management data are provided and explored for 33 initial subjects. Individuals who volunteer to participate in an online modality are eager to receive this home-based programming. They readily engaged with all aspects of the OSM program and experienced few difficulties navigating the environment. An OSM site provides a convenient, effective, and securely maintained health service, once restricted to clinic settings. The OSM application can be used to extend the benefits of SM programs to broad target audiences and serves as a model for the emerging generation of Internet-based clinical management/delivery systems.

  1. Applying the Dualistic Model of Passion to Post-Secondary Online Instruction: A Comparative Study

    ERIC Educational Resources Information Center

    Greenberger, Scott W.

    2013-01-01

    With the growth of online education, online student attrition and failure rates will continue to be a concern for post-secondary institutions. Although many factors may contribute to such phenomena, the role of the online instructor is clearly an important factor. Exploring how online instructors perceive their role as online teachers,…

  2. Applying the Dualistic Model of Passion to Post-Secondary Online Instruction: A Comparative Study

    ERIC Educational Resources Information Center

    Greenberger, Scott W.

    2013-01-01

    With the growth of online education, online student attrition and failure rates will continue to be a concern for post-secondary institutions. Although many factors may contribute to such phenomena, the role of the online instructor is clearly an important factor. Exploring how online instructors perceive their role as online teachers,…

  3. An approach to online identification of Takagi-Sugeno fuzzy models.

    PubMed

    Angelov, Plamen P; Filev, Dimitar P

    2004-02-01

    An approach to the online learning of Takagi-Sugeno (TS) type models is proposed in the paper. It is based on a novel learning algorithm that recursively updates TS model structure and parameters by combining supervised and unsupervised learning. The rule-base and parameters of the TS model continually evolve by adding new rules with more summarization power and by modifying existing rules and parameters. In this way, the rule-base structure is inherited and up-dated when new data become available. By applying this learning concept to the TS model we arrive at a new type adaptive model called the Evolving Takagi-Sugeno model (ETS). The adaptive nature of these evolving TS models in combination with the highly transparent and compact form of fuzzy rules makes them a promising candidate for online modeling and control of complex processes, competitive to neural networks. The approach has been tested on data from an air-conditioning installation serving a real building. The results illustrate the viability and efficiency of the approach. The proposed concept, however, has significantly wider implications in a number of fields, including adaptive nonlinear control, fault detection and diagnostics, performance analysis, forecasting, knowledge extraction, robotics, behavior modeling.

  4. Posterior Density Estimation for a Class of On-line Quality Control Models

    NASA Astrophysics Data System (ADS)

    Dorea, Chang C. Y.; Santos, Walter B.

    2011-11-01

    On-line quality control during production calls for a periodical monitoring of the produced items according to some prescribed strategy. It is reasonable to assume the existence of internal non-observable variables so that the carried out monitoring is only partially reliable. Under the setting of a Hidden Markov Model (HMM), posterior density estimates are obtained via particle filter type algorithms. Making use of kernel density methods the stable regime densities are approximated and false-alarm probabilities are estimated.

  5. Building Component Library: An Online Repository to Facilitate Building Energy Model Creation; Preprint

    SciTech Connect

    Fleming, K.; Long, N.; Swindler, A.

    2012-05-01

    This paper describes the Building Component Library (BCL), the U.S. Department of Energy's (DOE) online repository of building components that can be directly used to create energy models. This comprehensive, searchable library consists of components and measures as well as the metadata which describes them. The library is also designed to allow contributors to easily add new components, providing a continuously growing, standardized list of components for users to draw upon.

  6. Observer based on-line fault diagnosis of continuous systems modeled as Petri nets.

    PubMed

    Renganathan, K; Bhaskar, Vidhyacharan

    2010-10-01

    This paper describes a technique for achieving on-line fault diagnosis in continuous systems that are modeled using Petri nets. The effect of place markings and transition markings are considered and based on the computed error between the initial marking and subsequent markings evolved in time, the faults are categorized assuming that the markings are both observable and unobservable. An algorithm has been suitably proposed for achieving detection of faults for a typical continuous three tank system along with suitable results.

  7. An Assessment of a Physical Chemistry Online Activity

    NASA Astrophysics Data System (ADS)

    Hamby Towns, Marcy; Kreke, Kelley; Sauder, Deborah; Stout, Roland; Long, George; Zielinski, Theresa Julia

    1998-12-01

    A questionnaire and list server archive were used to investigate the perception of students and faculty who took part in a physical chemistry online project. Students at four universities worked cooperatively in their own classrooms and collaborated as a larger team on the Internet via a list server to determine the best mathematical model to describe the PV behavior of a gas at a specified temperature. The strengths of the project were the interaction among students, the use of Mathcad and modern technology, and the experience of authentic problem-solving. The weaknesses were the problems with the technology, the facilitation of interaction, and the student's ability to ask questions to solve an ill-defined problem. The suggestions for improvements focused on facilitating interuniversity interaction between students, clarifying tasks and goals, and implementation of the online activities. We discuss how our evaluation of the project guided and informed the design of a subsequent online project, and our planning for future projects. In addition, we describe the professional learning community that evolved among faculty who participated in this project.

  8. Online collaboration and model sharing in volcanology via VHub.org

    NASA Astrophysics Data System (ADS)

    Valentine, G.; Patra, A. K.; Bajo, J. V.; Bursik, M. I.; Calder, E.; Carn, S. A.; Charbonnier, S. J.; Connor, C.; Connor, L.; Courtland, L. M.; Gallo, S.; Jones, M.; Palma Lizana, J. L.; Moore-Russo, D.; Renschler, C. S.; Rose, W. I.

    2013-12-01

    VHub (short for VolcanoHub, and accessible at vhub.org) is an online platform for barrier free access to high end modeling and simulation and collaboration in research and training related to volcanoes, the hazards they pose, and risk mitigation. The underlying concept is to provide a platform, building upon the successful HUBzero software infrastructure (hubzero.org), that enables workers to collaborate online and to easily share information, modeling and analysis tools, and educational materials with colleagues around the globe. Collaboration occurs around several different points: (1) modeling and simulation; (2) data sharing; (3) education and training; (4) volcano observatories; and (5) project-specific groups. VHub promotes modeling and simulation in two ways: (1) some models can be implemented on VHub for online execution. VHub can provide a central warehouse for such models that should result in broader dissemination. VHub also provides a platform that supports the more complex CFD models by enabling the sharing of code development and problem-solving knowledge, benchmarking datasets, and the development of validation exercises. VHub also provides a platform for sharing of data and datasets. The VHub development team is implementing the iRODS data sharing middleware (see irods.org). iRODS allows a researcher to access data that are located at participating data sources around the world (a cloud of data) as if the data were housed in a single virtual database. Projects associated with VHub are also going to introduce the use of data driven workflow tools to support the use of multistage analysis processes where computing and data are integrated for model validation, hazard analysis etc. Audio-video recordings of seminars, PowerPoint slide sets, and educational simulations are all items that can be placed onto VHub for use by the community or by selected collaborators. An important point is that the manager of a given educational resource (or any other

  9. Online Denoising Based on the Second-Order Adaptive Statistics Model

    PubMed Central

    Yi, Sheng-Lun; Su, Ting-Li; Tang, Zhen-Yun; Wang, Fa-Fa; Xiang, Na; Kong, Jian-Lei

    2017-01-01

    Online denoising is motivated by real-time applications in the industrial process, where the data must be utilizable soon after it is collected. Since the noise in practical process is usually colored, it is quite a challenge for denoising techniques. In this paper, a novel online denoising method was proposed to achieve the processing of the practical measurement data with colored noise, and the characteristics of the colored noise were considered in the dynamic model via an adaptive parameter. The proposed method consists of two parts within a closed loop: the first one is to estimate the system state based on the second-order adaptive statistics model and the other is to update the adaptive parameter in the model using the Yule–Walker algorithm. Specifically, the state estimation process was implemented via the Kalman filter in a recursive way, and the online purpose was therefore attained. Experimental data in a reinforced concrete structure test was used to verify the effectiveness of the proposed method. Results show the proposed method not only dealt with the signals with colored noise, but also achieved a tradeoff between efficiency and accuracy. PMID:28726729

  10. Online and Certifiable Spectroscopy Courses Using Information and Communication Tools. a Model for Classrooms and Beyond

    NASA Astrophysics Data System (ADS)

    Krishnan, Mangala Sunder

    2015-06-01

    Online education tools and flipped (reverse) class models for teaching and learning and pedagogic and andragogic approaches to self-learning have become quite mature in the last few years because of the revolution in video, interactive software and social learning tools. Open Educational resources of dependable quality and variety are also becoming available throughout the world making the current era truly a renaissance period for higher education using Internet. In my presentation, I shall highlight structured course content preparation online in several areas of spectroscopy and also the design and development of virtual lab tools and kits for studying optical spectroscopy. Both elementary and advanced courses on molecular spectroscopy are currently under development jointly with researchers in other institutions in India. I would like to explore participation from teachers throughout the world in the teaching-learning process using flipped class methods for topics such as experimental and theoretical microwave spectroscopy of semi-rigid and non-rigid molecules, molecular complexes and aggregates. In addition, courses in Raman, Infrared spectroscopy experimentation and advanced electronic spectroscopy courses are also envisaged for free, online access. The National Programme on Technology Enhanced Learning (NPTEL) and the National Mission on Education through Information and Communication Technology (NMEICT) are two large Government of India funded initiatives for producing certified and self-learning courses with financial support for moderated discussion forums. The learning tools and interactive presentations so developed can be used in classrooms throughout the world using flipped mode of teaching. They are very much sought after by learners and researchers who are in other areas of learning but want to contribute to research and development through inter-disciplinary learning. NPTEL is currently is experimenting with Massive Open Online Course (MOOC

  11. File servers, networking, and supercomputers

    NASA Technical Reports Server (NTRS)

    Moore, Reagan W.

    1992-01-01

    One of the major tasks of a supercomputer center is managing the massive amount of data generated by application codes. A data flow analysis of the San Diego Supercomputer Center is presented that illustrates the hierarchical data buffering/caching capacity requirements and the associated I/O throughput requirements needed to sustain file service and archival storage. Usage paradigms are examined for both tightly-coupled and loosely-coupled file servers linked to the supercomputer by high-speed networks.

  12. File servers, networking, and supercomputers

    NASA Technical Reports Server (NTRS)

    Moore, Reagan W.

    1991-01-01

    One of the major tasks of a supercomputer center is managing the massive amount of data generated by application codes. A data flow analysis of the San Diego Supercomputer Center is presented that illustrates the hierarchical data buffering/caching capacity requirements and the associated I/O throughput requirements needed to sustain file service and archival storage. Usage paradigms are examined for both tightly-coupled and loosely-coupled file servers linked to the supercomputer by high-speed networks.

  13. The NASA Technical Report Server

    NASA Astrophysics Data System (ADS)

    Nelson, M. L.; Gottlich, G. L.; Bianco, D. J.; Paulson, S. S.; Binkley, R. L.; Kellogg, Y. D.; Beaumont, C. J.; Schmunk, R. B.; Kurtz, M. J.; Accomazzi, A.; Syed, O.

    The National Aeronautics and Space Act of 1958 established the National Aeronautics and Space Administration (NASA) and charged it to "provide for the widest practicable and appropriate dissemination of information concerning...its activities and the results thereof". The search for innovative methods to distribute NASA's information led a grass-roots team to create the NASA Technical Report Server (NTRS), which uses the World Wide Web and other popular Internet-based information systems .

  14. MARSIS data and simulation exploited using array databases: PlanetServer/EarthServer for sounding radars

    NASA Astrophysics Data System (ADS)

    Cantini, Federico; Pio Rossi, Angelo; Orosei, Roberto; Baumann, Peter; Misev, Dimitar; Oosthoek, Jelmer; Beccati, Alan; Campalani, Piero; Unnithan, Vikram

    2014-05-01

    parallel computing has been developed and tested on a Tier 0 class HPC cluster computer located at CINECA, Bologna, Italy, to produce accurate simulations for the entire MARSIS dataset. Although the necessary computational resources have not yet been secured, through the HPC cluster at Jacobs University in Bremen it was possible to simulate a significant subset of orbits covering the area of the Medusae Fossae Formation (MFF), a seeimingly soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars (e.g. Watters et al., 2007; Carter et al., 2009). Besides the MARSIS data, simulation of MARSIS surface clutter signal are included in the db to further improve its scientific value. Simulations will be available throught the project portal to end users/scientists and they will eventually be provided in the PSA/PDS archives. References: Baumann, P. On the management of multidimensional discrete data. VLDB J. 4 (3), 401-444, Special Issue on Spatial Database Systems, 1994. Carter, L. M., Campbell, B. A., Watters, T. R., Phillips, R. J., Putzig, N. E., Safaeinili, A., Plaut, J., Okubo, C., Egan, A. F., Biccari, D., Orosei, R. (2009). Shallow radar (SHARAD) sounding observations of the Medusae Fossae Formation, Mars. Icarus, 199(2), 295-302. Nouvel, J.-F., Herique, A., Kofman, W., Safaeinili, A. 2004. Radar signal simulation: Surface modeling with the Facet Method. Radio Science 39, 1013. Oosthoek, J.H.P, Flahaut J., Rossi, A. P., Baumann, P., Misev, D., Campalani, P., Unnithan, V. (2013) PlanetServer: Innovative Approaches for the Online Analysis of Hyperspectral Satellite Data from Mars, Advances in Space Research. DOI: 10.1016/j.asr.2013.07.002 Picardi, G., and 33 colleagues 2005. Radar Soundings of the Subsurface of Mars. Science 310, 1925-1928. Rossi, A. P., Baumann, P., Oosthoek, J., Beccati, A., Cantini, F., Misev, D. Orosei, R., Flahaut, J., Campalani, P., Unnithan, V. (2014),Geophys. Res. Abs., Vol. 16, #EGU2014-5149, this meeting. Watters, T. R

  15. A batch arrival queue under randomised multi-vacation policy with unreliable server and repair

    NASA Astrophysics Data System (ADS)

    Ke, Jau-Chuan; Huang, Kai-Bin; Pearn, Wen Lea

    2012-03-01

    This article examines an M[x]/G/1 queueing system with an unreliable server and a repair, in which the server operates a randomised vacation policy with multiple available vacations. Upon the system being found to be empty, the server immediately takes a vacation. If there is at least one customer found waiting in the queue upon returning from a vacation, the server will be activated for service. Otherwise, if no customers are waiting for service at the end of a vacation, the server either remains idle with probability p or leaves for another vacation with probability 1 - p. When one or more customers arrive when the server is idle, the server immediately starts providing service for the arrivals. It is possible that an unpredictable breakdown may occur in the server, in which case a repair time is requested. For such a system, we derive the distributions of several important system characteristics, such as the system size distribution at a random epoch and at a departure epoch, the system size distribution at the busy period initiation epoch, and the distribution of the idle and busy periods. We perform a numerical analysis for changes in the system characteristics, along with changes in specific values of the system parameters. A cost effectiveness maximisation model is constructed to show the benefits of such a queueing system.

  16. HMMER web server: interactive sequence similarity searching.

    PubMed

    Finn, Robert D; Clements, Jody; Eddy, Sean R

    2011-07-01

    HMMER is a software suite for protein sequence similarity searches using probabilistic methods. Previously, HMMER has mainly been available only as a computationally intensive UNIX command-line tool, restricting its use. Recent advances in the software, HMMER3, have resulted in a 100-fold speed gain relative to previous versions. It is now feasible to make efficient profile hidden Markov model (profile HMM) searches via the web. A HMMER web server (http://hmmer.janelia.org) has been designed and implemented such that most protein database searches return within a few seconds. Methods are available for searching either a single protein sequence, multiple protein sequence alignment or profile HMM against a target sequence database, and for searching a protein sequence against Pfam. The web server is designed to cater to a range of different user expertise and accepts batch uploading of multiple queries at once. All search methods are also available as RESTful web services, thereby allowing them to be readily integrated as remotely executed tasks in locally scripted workflows. We have focused on minimizing search times and the ability to rapidly display tabular results, regardless of the number of matches found, developing graphical summaries of the search results to provide quick, intuitive appraisement of them.

  17. HMMER web server: interactive sequence similarity searching

    PubMed Central

    Finn, Robert D.; Clements, Jody; Eddy, Sean R.

    2011-01-01

    HMMER is a software suite for protein sequence similarity searches using probabilistic methods. Previously, HMMER has mainly been available only as a computationally intensive UNIX command-line tool, restricting its use. Recent advances in the software, HMMER3, have resulted in a 100-fold speed gain relative to previous versions. It is now feasible to make efficient profile hidden Markov model (profile HMM) searches via the web. A HMMER web server (http://hmmer.janelia.org) has been designed and implemented such that most protein database searches return within a few seconds. Methods are available for searching either a single protein sequence, multiple protein sequence alignment or profile HMM against a target sequence database, and for searching a protein sequence against Pfam. The web server is designed to cater to a range of different user expertise and accepts batch uploading of multiple queries at once. All search methods are also available as RESTful web services, thereby allowing them to be readily integrated as remotely executed tasks in locally scripted workflows. We have focused on minimizing search times and the ability to rapidly display tabular results, regardless of the number of matches found, developing graphical summaries of the search results to provide quick, intuitive appraisement of them. PMID:21593126

  18. A fully-online Neuro-Fuzzy model for flow forecasting in basins with limited data

    NASA Astrophysics Data System (ADS)

    Ashrafi, Mohammad; Chua, Lloyd Hock Chye; Quek, Chai; Qin, Xiaosheng

    2017-02-01

    Current state-of-the-art online neuro fuzzy models (NFMs) such as DENFIS (Dynamic Evolving Neural-Fuzzy Inference System) have been used for runoff forecasting. Online NFMs adopt a local learning approach and are able to adapt to changes continuously. The DENFIS model however requires upper/lower bound for normalization and also the number of rules increases monotonically. This requirement makes the model unsuitable for use in basins with limited data, since a priori data is required. In order to address this and other drawbacks of current online models, the Generic Self-Evolving Takagi-Sugeno-Kang (GSETSK) is adopted in this study for forecast applications in basins with limited data. GSETSK is a fully-online NFM which updates its structure and parameters based on the most recent data. The model does not require the need for historical data and adopts clustering and rule pruning techniques to generate a compact and up-to-date rule-base. GSETSK was used in two forecast applications, rainfall-runoff (a catchment in Sweden) and river routing (Lower Mekong River) forecasts. Each of these two applications was studied under two scenarios: (i) there is no prior data, and (ii) only limited data is available (1 year for the Swedish catchment and 1 season for the Mekong River). For the Swedish Basin, GSETSK model results were compared to available results from a calibrated HBV (Hydrologiska Byråns Vattenbalansavdelning) model. For the Mekong River, GSETSK results were compared against the URBS (Unified River Basin Simulator) model. Both comparisons showed that results from GSETSK are comparable with the physically based models, which were calibrated with historical data. Thus, even though GSETSK was trained with a very limited dataset in comparison with HBV or URBS, similar results were achieved. Similarly, further comparisons between GSETSK with DENFIS and the RBF (Radial Basis Function) models highlighted further advantages of GSETSK as having a rule-base (compared to

  19. Mind the Gap: Enabling Online Faculty and Instructional Designers in Mapping New Models for Quality Online Courses

    ERIC Educational Resources Information Center

    Scoppio, Grazia; Luyt, Ilka

    2017-01-01

    Distance education has provided the foundation for new generations of learning, including courses delivered through various web-based educational technologies, also referred to as online learning. Many post-secondary institutions face the challenge of creating processes and systems to support instructors who are required to design, deliver, and…

  20. The Online Theology Classroom: Strategies for Engaging a Community of Distance Learners in a Hybrid Model of Online Education

    ERIC Educational Resources Information Center

    Hege, Brent A. R.

    2011-01-01

    One factor contributing to success in online education is the creation of a safe and vibrant virtual community and sustained, lively engagement with that community of learners. In order to create and engage such a community instructors must pay special attention to the relationship between technology and pedagogy, specifically in terms of issues…

  1. Web Server Security on Open Source Environments

    NASA Astrophysics Data System (ADS)

    Gkoutzelis, Dimitrios X.; Sardis, Manolis S.

    Administering critical resources has never been more difficult that it is today. In a changing world of software innovation where major changes occur on a daily basis, it is crucial for the webmasters and server administrators to shield their data against an unknown arsenal of attacks in the hands of their attackers. Up until now this kind of defense was a privilege of the few, out-budgeted and low cost solutions let the defender vulnerable to the uprising of innovating attacking methods. Luckily, the digital revolution of the past decade left its mark, changing the way we face security forever: open source infrastructure today covers all the prerequisites for a secure web environment in a way we could never imagine fifteen years ago. Online security of large corporations, military and government bodies is more and more handled by open source application thus driving the technological trend of the 21st century in adopting open solutions to E-Commerce and privacy issues. This paper describes substantial security precautions in facing privacy and authentication issues in a totally open source web environment. Our goal is to state and face the most known problems in data handling and consequently propose the most appealing techniques to face these challenges through an open solution.

  2. Context modeling for text/non-text separation in free-form online handwritten documents

    NASA Astrophysics Data System (ADS)

    Delaye, Adrien; Liu, Cheng-Lin

    2013-01-01

    Free-form online handwritten documents contain a high diversity of content, organized without constraints imposed to the user. The lack of prior knowledge about content and layout makes the modeling of contextual information of crucial importance for interpretation of such documents. In this work, we present a comprehensive investigation of the sources of contextual information that can benefit the task of discerning textual from non-textual strokes in handwritten online documents. An in-depth analysis of interactions between strokes is conducted through the design of various pairwise clique systems that are combined within a Conditional Random Field formulation of the stroke labeling problem. Our results demonstrate the benefits of combining complementary sources of context for improving the text/non-text recognition performance.

  3. On-line monitoring of pharmaceutical production processes using Hidden Markov Model.

    PubMed

    Zhang, Hui; Jiang, Zhuangde; Pi, J Y; Xu, H K; Du, R

    2009-04-01

    This article presents a new method for on-line monitoring of pharmaceutical production process, especially the powder blending process. The new method consists of two parts: extracting features from the Near Infrared (NIR) spectroscopy signals and recognizing patterns from the features. Features are extracted from spectra by using Partial Least Squares method (PLS). The pattern recognition is done by using Hidden Markov Model (HMM). A series of experiments are conducted to evaluate the effectiveness of this new method. In the experiments, wheat powder and corn powder are blended together at a set concentration. The proposed method can effectively detect the blending uniformity (the success rate is 99.6%). In comparison to the conventional Moving Block of Standard Deviation (MBSD), the proposed method has a number of advantages, including higher reliability, higher robustness and more transparent decision making. It can be used for effective on-line monitoring of pharmaceutical production processes.

  4. A study of critical reasoning in online learning: application of the Occupational Performance Process Model.

    PubMed

    Mitchell, Anita Witt; Batorski, Rosemary E

    2009-01-01

    This study examined the effect of an online guided independent study on critical reasoning skills. Twenty-one first-semester Master of Occupational Therapy students completed an online assignment designed to facilitate application of the Occupational Performance Process Model (Fearing & Clark) and kept reflective journals. Data from the journals were analyzed in relation to the three sets of questions, question type and results of the Watson-Glaser Critical Thinking Appraisal (WGCTA). This assignment appeared to be effective for enhancing awareness and use of critical reasoning skills. Differences in patterns of critical reasoning between students with high and low WGCTA scores and results of an inductive analysis of the journal entries are discussed. Future research investigating the types of feedback that effectively facilitate development of critical reasoning and whether students with high and low WGCTA scores might benefit from different types of instruction and/or feedback is recommended.

  5. Use of Online Forums for Perinatal Mental Illness, Stigma, and Disclosure: An Exploratory Model.

    PubMed

    Moore, Donna; Drey, Nicholas; Ayers, Susan

    2017-02-20

    Perinatal mental illness is a global health concern; however, many women with the illness do not get the treatment they need to recover. Interventions that reduce the stigma around perinatal mental illness have the potential to enable women to disclose their symptoms to health care providers and consequently access treatment. There are many online forums for perinatal mental illness and thousands of women use them. Preliminary research suggests that online forums may promote help-seeking behavior, potentially because they have a role in challenging stigma. This study draws from these findings and theoretical concepts to present a model of forum use, stigma, and disclosure. This study tested a model that measured the mediating role of stigma between online forum use and disclosure of affective symptoms to health care providers. A Web-based survey of 200 women who were pregnant or had a child younger than 5 years and considered themselves to be experiencing psychological distress was conducted. Women were recruited through social media and questions measured forum usage, perinatal mental illness stigma, disclosure to health care providers, depression and anxiety symptoms, barriers to disclosure, and demographic information. There was a significant positive indirect effect of length of forum use on disclosure of symptoms through internal stigma, b=0.40, bias-corrected and accelerated (BCa) 95% CI 0.13-0.85. Long-term forum users reported higher levels of internal stigma, and higher internal stigma was associated with disclosure of symptoms to health care providers when controlling for symptoms of depression and anxiety. Internal stigma mediates the relationship between length of forum use and disclosure to health care providers. Findings suggest that forums have the potential to enable women to recognize and reveal their internal stigma, which may in turn lead to greater disclosure of symptoms to health care providers. Clinicians could refer clients to trustworthy and

  6. Oceanotron, Scalable Server for Marine Observations

    NASA Astrophysics Data System (ADS)

    Loubrieu, T.; Bregent, S.; Blower, J. D.; Griffiths, G.

    2013-12-01

    Ifremer, French marine institute, is deeply involved in data management for different ocean in-situ observation programs (ARGO, OceanSites, GOSUD, ...) or other European programs aiming at networking ocean in-situ observation data repositories (myOcean, seaDataNet, Emodnet). To capitalize the effort for implementing advance data dissemination services (visualization, download with subsetting) for these programs and generally speaking water-column observations repositories, Ifremer decided to develop the oceanotron server (2010). Knowing the diversity of data repository formats (RDBMS, netCDF, ODV, ...) and the temperamental nature of the standard interoperability interface profiles (OGC/WMS, OGC/WFS, OGC/SOS, OpeNDAP, ...), the server is designed to manage plugins: - StorageUnits : which enable to read specific data repository formats (netCDF/OceanSites, RDBMS schema, ODV binary format). - FrontDesks : which get external requests and send results for interoperable protocols (OGC/WMS, OGC/SOS, OpenDAP). In between a third type of plugin may be inserted: - TransformationUnits : which enable ocean business related transformation of the features (for example conversion of vertical coordinates from pressure in dB to meters under sea surface). The server is released under open-source license so that partners can develop their own plugins. Within MyOcean project, University of Reading has plugged a WMS implementation as an oceanotron frontdesk. The modules are connected together by sharing the same information model for marine observations (or sampling features: vertical profiles, point series and trajectories), dataset metadata and queries. The shared information model is based on OGC/Observation & Measurement and Unidata/Common Data Model initiatives. The model is implemented in java (http://www.ifremer.fr/isi/oceanotron/javadoc/). This inner-interoperability level enables to capitalize ocean business expertise in software development without being indentured to

  7. psRNATarget: a plant small RNA target analysis server

    PubMed Central

    Dai, Xinbin; Zhao, Patrick Xuechun

    2011-01-01

    Plant endogenous non-coding short small RNAs (20–24 nt), including microRNAs (miRNAs) and a subset of small interfering RNAs (ta-siRNAs), play important role in gene expression regulatory networks (GRNs). For example, many transcription factors and development-related genes have been reported as targets of these regulatory small RNAs. Although a number of miRNA target prediction algorithms and programs have been developed, most of them were designed for animal miRNAs which are significantly different from plant miRNAs in the target recognition process. These differences demand the development of separate plant miRNA (and ta-siRNA) target analysis tool(s). We present psRNATarget, a plant small RNA target analysis server, which features two important analysis functions: (i) reverse complementary matching between small RNA and target transcript using a proven scoring schema, and (ii) target-site accessibility evaluation by calculating unpaired energy (UPE) required to ‘open’ secondary structure around small RNA’s target site on mRNA. The psRNATarget incorporates recent discoveries in plant miRNA target recognition, e.g. it distinguishes translational and post-transcriptional inhibition, and it reports the number of small RNA/target site pairs that may affect small RNA binding activity to target transcript. The psRNATarget server is designed for high-throughput analysis of next-generation data with an efficient distributed computing back-end pipeline that runs on a Linux cluster. The server front-end integrates three simplified user-friendly interfaces to accept user-submitted or preloaded small RNAs and transcript sequences; and outputs a comprehensive list of small RNA/target pairs along with the online tools for batch downloading, key word searching and results sorting. The psRNATarget server is freely available at http://plantgrn.noble.org/psRNATarget/. PMID:21622958

  8. Smooth Function Modeling for On-Line Trajectory Reshaping Application (Preprint)

    DTIC Science & Technology

    2006-02-01

    A. N., and Arsenin , V. Y., “ Solutions of ill - posed problems ,”: Winston, Washington DC 1977 20 Jancaitis, J.R., and Junkins J.L., “Modeling N...dynamical system is a solution of a two-point boundary value problem for a set of governing differential equation of motion. The real world systems such as...AFRL- VA -WP-TP-2006-316 SMOOTH FUNCTION MODELING FOR ON-LINE TRAJECTORY RESHAPING APPLICATION (PREPRINT) Ajay Verma, Kaylan Vadakkeveedu

  9. A risk evaluation model and its application in online retailing trustfulness

    NASA Astrophysics Data System (ADS)

    Ye, Ruyi; Xu, Yingcheng

    2017-08-01

    Building a general model for risks evaluation in advance could improve the convenience, normality and comparability of the results of repeating risks evaluation in the case that the repeating risks evaluating are in the same area and for a similar purpose. One of the most convenient and common risks evaluation models is an index system including of several index, according weights and crediting method. One method to build a risk evaluation index system that guarantees the proportional relationship between the resulting credit and the expected risk loss is proposed and an application example is provided in online retailing in this article.

  10. Adaptive hidden Markov model-based online learning framework for bearing faulty detection and performance degradation monitoring

    NASA Astrophysics Data System (ADS)

    Yu, Jianbo

    2017-01-01

    This study proposes an adaptive-learning-based method for machine faulty detection and health degradation monitoring. The kernel of the proposed method is an "evolving" model that uses an unsupervised online learning scheme, in which an adaptive hidden Markov model (AHMM) is used for online learning the dynamic health changes of machines in their full life. A statistical index is developed for recognizing the new health states in the machines. Those new health states are then described online by adding of new hidden states in AHMM. Furthermore, the health degradations in machines are quantified online by an AHMM-based health index (HI) that measures the similarity between two density distributions that describe the historic and current health states, respectively. When necessary, the proposed method characterizes the distinct operating modes of the machine and can learn online both abrupt as well as gradual health changes. Our method overcomes some drawbacks of the HIs (e.g., relatively low comprehensibility and applicability) based on fixed monitoring models constructed in the offline phase. Results from its application in a bearing life test reveal that the proposed method is effective in online detection and adaptive assessment of machine health degradation. This study provides a useful guide for developing a condition-based maintenance (CBM) system that uses an online learning method without considerable human intervention.

  11. OneRTM: an online real-time modelling platform for the next generation of numerical environmental modelling

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Kingdon, Andrew

    2014-05-01

    Numerical modelling has been applied in many fields to better understand and predict the behaviours of different processes. In our increasingly dynamic world there is an imperative to identify potential stresses and threats in the environment and to respond quickly with sound decisions. However, the limitations in traditional modelling methodologies make it difficult to respond quickly to rapidly developing environmental events, such as floods, droughts and pollution incidents. For example, it is both time consuming and costly to keep model data up-to-date and also to disseminate models results and modelled output datasets to end-users. Crucially it is difficult for people who has limited numerical modelling skills to understand and interact with models and modelled results. In response to these challenges, a proof-of-concept online real-time modelling platform (OneRTM) has been developed as a mechanism for maintaining and disseminating numerical models and datasets. This automatically keeps models current for the most recent input data, links models based on data flow; it makes models and modelled datasets (historic, real-time and forecasted) immediately available via the internet as easy-to-understand dynamic GIS layers and graphs; and it provides online modelling functions to allow non-modellers to manipulate model including running pre-defined scenarios with a few mouse clicks. OneRTM has been successfully applied and tested in the Chalk groundwater flow modelling in the Thames Basin, UK. The system hosts and links groundwater recharge and groundwater flow models in the case study area, and automatically publishes the latest groundwater level layers on the internet once the current weather datasets becomes available. It also provides online functions of generating groundwater hydrograph and running groundwater abstraction scenarios. Although OneRTM is currently tested using groundwater flow modelling as an example, it could be further developed into a platform

  12. UniTree Name Server internals

    SciTech Connect

    Mecozzi, D.; Minton, J.

    1996-01-01

    The UniTree Name Server (UNS) is one of several servers which make up the UniTree storage system. The Name Server is responsible for mapping names to capabilities Names are generally human readable ASCII strings of any length. Capabilities are unique 256-bit identifiers that point to files, directories, or symbolic links. The Name Server implements a UNIX style hierarchical directory structure to facilitate name-to-capability mapping. The principal task of the Name Server is to manage the directories which make up the UniTree directory structure. The principle clients of the Name Server are the FTP Daemon, NFS and a few UniTree utility routines. However, the Name Server is a generalized server and will accept messages from any client. The purpose of this paper is to describe the internal workings of the UniTree Name Server. In cases where it seems appropriate, the motivation for a particular choice of algorithm as description of the algorithm itself will be given.

  13. National Medical Terminology Server in Korea

    NASA Astrophysics Data System (ADS)

    Lee, Sungin; Song, Seung-Jae; Koh, Soonjeong; Lee, Soo Kyoung; Kim, Hong-Gee

    Interoperable EHR (Electronic Health Record) necessitates at least the use of standardized medical terminologies. This paper describes a medical terminology server, LexCare Suite, which houses terminology management applications, such as a terminology editor, and a terminology repository populated with international standard terminology systems such as Systematized Nomenclature of Medicine (SNOMED). The server is to satisfy the needs of quality terminology systems to local primary to tertiary hospitals. Our partner general hospitals have used the server to test its applicability. This paper describes the server and the results of the applicability test.

  14. Factors affecting patients' online health information-seeking behaviours: The role of the Patient Health Engagement (PHE) Model.

    PubMed

    Graffigna, Guendalina; Barello, Serena; Bonanomi, Andrea; Riva, Giuseppe

    2017-10-01

    To identify the variables affecting patients' online health information-seeking behaviours by examining the relationships between patient participation in their healthcare and online health information-seeking behaviours. A cross-sectional survey of Italian chronic patients (N=352) was conducted on patient's online health information-seeking behaviours and patient participation-related variables. Structural equation modeling analysis was conducted to test the hypothesis. This study showed how the healthcare professionals' ability to support chronic patients' autonomy affect patients' participation in their healthcare and patient's online health information-seeking behaviours. However, results do not confirm that the frequency of patients' online health-information seeking behavior has an impact on their adherence to medical prescriptions. Assuming a psychosocial perspective, we have discussed how patients' engagement - conceived as the level of their emotional elaboration of the health condition - affects the patients' ability to search for and manage online health information. To improve the effectiveness of patients' online health information-seeking behaviours and to enhance the effectiveness of technological interventions in this field, healthcare providers should target assessing and improving patient engagement and patient empowerment in their healthcare. It is important that health professionals acknowledge patients' online health information-seeking behaviours that they discuss the information offered by patients and guide them to reliable and accurate web sources. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. The PhyloFacts FAT-CAT web server: ortholog identification and function prediction using fast approximate tree classification.

    PubMed

    Afrasiabi, Cyrus; Samad, Bushra; Dineen, David; Meacham, Christopher; Sjölander, Kimmen

    2013-07-01

    The PhyloFacts 'Fast Approximate Tree Classification' (FAT-CAT) web server provides a novel approach to ortholog identification using subtree hidden Markov model-based placement of protein sequences to phylogenomic orthology groups in the PhyloFacts database. Results on a data set of microbial, plant and animal proteins demonstrate FAT-CAT's high precision at separating orthologs and paralogs and robustness to promiscuous domains. We also present results documenting the precision of ortholog identification based on subtree hidden Markov model scoring. The FAT-CAT phylogenetic placement is used to derive a functional annotation for the query, including confidence scores and drill-down capabilities. PhyloFacts' broad taxonomic and functional coverage, with >7.3 M proteins from across the Tree of Life, enables FAT-CAT to predict orthologs and assign function for most sequence inputs. Four pipeline parameter presets are provided to handle different sequence types, including partial sequences and proteins containing promiscuous domains; users can also modify individual parameters. PhyloFacts trees matching the query can be viewed interactively online using the PhyloScope Javascript tree viewer and are hyperlinked to various external databases. The FAT-CAT web server is available at http://phylogenomics.berkeley.edu/phylofacts/fatcat/.

  16. Offline and online detection of damage using autoregressive models and artificial neural networks

    NASA Astrophysics Data System (ADS)

    Omenzetter, Piotr; de Lautour, Oliver R.

    2007-04-01

    Developed to study long, regularly sampled streams of data, time series analysis methods are being increasingly investigated for the use of Structural Health Monitoring. In this research, Autoregressive (AR) models are used in conjunction with Artificial Neural Networks (ANNs) for damage detection, localisation and severity assessment. In the first reported experimental exercise, AR models were used offline to fit the acceleration time histories of a 3-storey test structure in undamaged and various damaged states when excited by earthquake motion simulated on a shake table. Damage was introduced into the structure by replacing the columns with those of a thinner thickness. Analytical models of the structure in both damaged and undamaged states were also developed and updated using experimental data in order to determine structural stiffness. The coefficients of AR models were used as damage sensitive features and input into an ANN to build a relationship between them and the remaining structural stiffness. In the second, analytical exercise, a system with gradually progressing damage was numerically simulated and acceleration AR models with exogenous inputs were identified recursively. A trained ANN was then required to trace the structural stiffness online. The results for the offline and online approach showed the efficiency of using AR coefficient as damage sensitive features and good performance of the ANNs for damage detection, localization and quantification.

  17. An Online Database for Informing Ecological Network Models: http://kelpforest.ucsc.edu

    PubMed Central

    Beas-Luna, Rodrigo; Novak, Mark; Carr, Mark H.; Tinker, Martin T.; Black, August; Caselle, Jennifer E.; Hoban, Michael; Malone, Dan; Iles, Alison

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/databaseui). PMID:25343723

  18. Regional effects of atmospheric aerosols on temperature: an evaluation of an ensemble of online coupled models

    NASA Astrophysics Data System (ADS)

    Baró, Rocío; Palacios-Peña, Laura; Baklanov, Alexander; Balzarini, Alessandra; Brunner, Dominik; Forkel, Renate; Hirtl, Marcus; Honzak, Luka; Pérez, Juan Luis; Pirovano, Guido; San José, Roberto; Schröder, Wolfram; Werhahn, Johannes; Wolke, Ralf; Žabkar, Rahela; Jiménez-Guerrero, Pedro

    2017-08-01

    The climate effect of atmospheric aerosols is associated with their influence on the radiative budget of the Earth due to the direct aerosol-radiation interactions (ARIs) and indirect effects, resulting from aerosol-cloud-radiation interactions (ACIs). Online coupled meteorology-chemistry models permit the description of these effects on the basis of simulated atmospheric aerosol concentrations, although there is still some uncertainty associated with the use of these models. Thus, the objective of this work is to assess whether the inclusion of atmospheric aerosol radiative feedbacks of an ensemble of online coupled models improves the simulation results for maximum, mean and minimum temperature at 2 m over Europe. The evaluated models outputs originate from EuMetChem COST Action ES1004 simulations for Europe, differing in the inclusion (or omission) of ARI and ACI in the various models. The cases studies cover two important atmospheric aerosol episodes over Europe in the year 2010: (i) a heat wave event and a forest fire episode (July-August 2010) and (ii) a more humid episode including a Saharan desert dust outbreak in October 2010. The simulation results are evaluated against observational data from the E-OBS gridded database. The results indicate that, although there is only a slight improvement in the bias of the simulation results when including the radiative feedbacks, the spatiotemporal variability and correlation coefficients are improved for the cases under study when atmospheric aerosol radiative effects are included.

  19. An online database for informing ecological network models: http://kelpforest.ucsc.edu.

    PubMed

    Beas-Luna, Rodrigo; Novak, Mark; Carr, Mark H; Tinker, Martin T; Black, August; Caselle, Jennifer E; Hoban, Michael; Malone, Dan; Iles, Alison

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/databaseui).

  20. An online database for informing ecological network models: http://kelpforest.ucsc.edu

    USGS Publications Warehouse

    Beas-Luna, Rodrigo; Tinker, M. Tim; Novak, Mark; Carr, Mark H.; Black, August; Caselle, Jennifer E.; Hoban, Michael; Malone, Dan; Iles, Alison C.

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/data​baseui).

  1. DelPhi web server v2: incorporating atomic-style geometrical figures into the computational protocol.

    PubMed

    Smith, Nicholas; Witham, Shawn; Sarkar, Subhra; Zhang, Jie; Li, Lin; Li, Chuan; Alexov, Emil

    2012-06-15

    A new edition of the DelPhi web server, DelPhi web server v2, is released to include atomic presentation of geometrical figures. These geometrical objects can be used to model nano-size objects together with real biological macromolecules. The position and size of the object can be manipulated by the user in real time until desired results are achieved. The server fixes structural defects, adds hydrogen atoms and calculates electrostatic energies and the corresponding electrostatic potential and ionic distributions. The web server follows a client-server architecture built on PHP and HTML and utilizes DelPhi software. The computation is carried out on supercomputer cluster and results are given back to the user via http protocol, including the ability to visualize the structure and corresponding electrostatic potential via Jmol implementation. The DelPhi web server is available from http://compbio.clemson.edu/delphi_webserver.

  2. On-line classification and prediction of eye movements by multiple-model Kalman filtering.

    PubMed

    Kohlbecher, Stefan; Schneider, Erich

    2009-05-01

    An extensible multiple-model Kalman filter framework for eye tracking and video-oculography (VOG) applications is proposed. The Kalman filter predicts future states of a system on the basis of a mathematical model and previous measurements. The predicted values are then compared against the current measurements. In a correcting step, the predicted state is enhanced by the measurements. In this work, the Kalman filter is used for smoothing the VOG data, for on-line classification of eye movements, as well as for predictive real-time control of a gaze-driven head-mounted camera (EyeSeeCam). With multiple models running in parallel, it was possible to distinguish between fixations, slow-phase eye movements, and saccades. Under the assumption that each class of eye movement follows a distinct model, one can decide which types of eye movement occurred by evaluating the probability for each model.

  3. Using a Comprehensive Model to Test and Predict the Factors of Online Learning Effectiveness

    ERIC Educational Resources Information Center

    He, Minyan

    2013-01-01

    As online learning is an important part of higher education, the effectiveness of online learning has been tested with different methods. Although the literature regarding online learning effectiveness has been related to various factors, a more comprehensive review of the factors may result in broader understanding of online learning…

  4. PlanetServer/EarthServer: Big Data analytics in Planetary Science

    NASA Astrophysics Data System (ADS)

    Pio Rossi, Angelo; Oosthoek, Jelmer; Baumann, Peter; Beccati, Alan; Cantini, Federico; Misev, Dimitar; Orosei, Roberto; Flahaut, Jessica; Campalani, Piero; Unnithan, Vikram

    2014-05-01

    Planetary data are freely available on PDS/PSA archives and alike (e.g. Heather et al., 2013). Their exploitation by the community is somewhat limited by the variable availability of calibrated/higher level datasets. An additional complexity of these multi-experiment, multi-mission datasets is related to the heterogeneity of data themselves, rather than their volume. Orbital - so far - data are best suited for an inclusion in array databases (Baumann et al., 1994). Most lander- or rover-based remote sensing experiment (and possibly, in-situ as well) are suitable for similar approaches, although the complexity of coordinate reference systems (CRS) is higher in the latter case. PlanetServer, the Planetary Service of the EC FP7 e-infrastructure project EarthServer (http://earthserver.eu) is a state-of-art online data exploration and analysis system based on the Open Geospatial Consortium (OGC) standards for Mars orbital data. It provides access to topographic, panchromatic, multispectral and hyperspectral calibrated data. While its core focus has been on hyperspectral data analysis through the OGC Web Coverage Processing Service (Oosthoek et al., 2013; Rossi et al., 2013), the Service progressively expanded to host also sounding radar data (Cantini et al., this volume). Additionally, both single swath and mosaicked imagery and topographic data are being added to the Service, deriving from the HRSC experiment (e.g. Jaumann et al., 2007; Gwinner et al., 2009) The current Mars-centric focus can be extended to other planetary bodies and most components are general purpose ones, making possible its application to the Moon, Mercury or alike. The Planetary Service of EarthServer is accessible on http://www.planetserver.eu References: Baumann, P. (1994) VLDB J. 4 (3), 401-444, Special Issue on Spatial Database Systems. Cantini, F. et al. (2014) Geophys. Res. Abs., Vol. 16, #EGU2014-3784, this volume Heather, D., et al.(2013) EuroPlanet Sci. Congr. #EPSC2013-626 Gwinner, K

  5. RNA-Redesign: a web server for fixed-backbone 3D design of RNA.

    PubMed

    Yesselman, Joseph D; Das, Rhiju

    2015-07-01

    RNA is rising in importance as a design medium for interrogating fundamental biology and for developing therapeutic and bioengineering applications. While there are several online servers for design of RNA secondary structure, there are no tools available for the rational design of 3D RNA structure. Here we present RNA-Redesign (http://rnaredesign.stanford.edu), an online 3D design tool for RNA. This resource utilizes fixed-backbone design to optimize the sequence identity and nucleobase conformations of an RNA to match a desired backbone, analogous to fundamental tools that underlie rational protein engineering. The resulting sequences suggest thermostabilizing mutations that can be experimentally verified. Further, sequence preferences that differ between natural and computationally designed sequences can suggest whether natural sequences possess functional constraints besides folding stability, such as cofactor binding or conformational switching. Finally, for biochemical studies, the designed sequences can suggest experimental tests of 3D models, including concomitant mutation of base triples. In addition to the designs generated, detailed graphical analysis is presented through an integrated and user-friendly environment.

  6. Observing Consistency in Online Communication Patterns for User Re-Identification

    PubMed Central

    Venter, Hein S.

    2016-01-01

    Comprehension of the statistical and structural mechanisms governing human dynamics in online interaction plays a pivotal role in online user identification, online profile development, and recommender systems. However, building a characteristic model of human dynamics on the Internet involves a complete analysis of the variations in human activity patterns, which is a complex process. This complexity is inherent in human dynamics and has not been extensively studied to reveal the structural composition of human behavior. A typical method of anatomizing such a complex system is viewing all independent interconnectivity that constitutes the complexity. An examination of the various dimensions of human communication pattern in online interactions is presented in this paper. The study employed reliable server-side web data from 31 known users to explore characteristics of human-driven communications. Various machine-learning techniques were explored. The results revealed that each individual exhibited a relatively consistent, unique behavioral signature and that the logistic regression model and model tree can be used to accurately distinguish online users. These results are applicable to one-to-one online user identification processes, insider misuse investigation processes, and online profiling in various areas. PMID:27918593

  7. Observing Consistency in Online Communication Patterns for User Re-Identification.

    PubMed

    Adeyemi, Ikuesan Richard; Razak, Shukor Abd; Salleh, Mazleena; Venter, Hein S

    2016-01-01

    Comprehension of the statistical and structural mechanisms governing human dynamics in online interaction plays a pivotal role in online user identification, online profile development, and recommender systems. However, building a characteristic model of human dynamics on the Internet involves a complete analysis of the variations in human activity patterns, which is a complex process. This complexity is inherent in human dynamics and has not been extensively studied to reveal the structural composition of human behavior. A typical method of anatomizing such a complex system is viewing all independent interconnectivity that constitutes the complexity. An examination of the various dimensions of human communication pattern in online interactions is presented in this paper. The study employed reliable server-side web data from 31 known users to explore characteristics of human-driven communications. Various machine-learning techniques were explored. The results revealed that each individual exhibited a relatively consistent, unique behavioral signature and that the logistic regression model and model tree can be used to accurately distinguish online users. These results are applicable to one-to-one online user identification processes, insider misuse investigation processes, and online profiling in various areas.

  8. The PredictProtein server.

    PubMed

    Rost, Burkhard; Liu, Jinfeng

    2003-07-01

    PredictProtein (PP, http://cubic.bioc.columbia.edu/pp/) is an internet service for sequence analysis and the prediction of aspects of protein structure and function. Users submit protein sequence or alignments; the server returns a multiple sequence alignment, PROSITE sequence motifs, low-complexity regions (SEG), ProDom domain assignments, nuclear localisation signals, regions lacking regular structure and predictions of secondary structure, solvent accessibility, globular regions, transmembrane helices, coiled-coil regions, structural switch regions and disulfide-bonds. Upon request, fold recognition by prediction-based threading is available. For all services, users can submit their query either by electronic mail or interactively from World Wide Web.

  9. Microfluidic droplet-based liquid-liquid extraction: online model validation.

    PubMed

    Lubej, Martin; Novak, Uroš; Liu, Mingqiang; Martelanc, Mitja; Franko, Mladen; Plazl, Igor

    2015-05-21

    Droplet-based liquid-liquid extraction in a microchannel was studied, both theoretically and experimentally. A full 3D mathematical model, incorporating convection and diffusion in all spatial directions along with the velocity profile, was developed to depict the governing transport characteristics of droplet-based microfluidics. The finite elements method, as the most common macroscale simulation technique, was used to solve the set of differential equations regarding conservation of moment, mass and solute concentration in a two-domain system coupled by interfacial surface of droplet-based flow pattern. The model was numerically verified and validated online by following the concentrations of a solute in two phases within the microchannel. The relative azobenzene concentration profiles in a methanol/n-octane two-phase system at different positions along the channel length were retrieved by means of a thermal lens microscopic (TLM) technique coupled to a microfluidic system, which gave results of high spatial and temporal resolution. Very good agreement between model calculations and online experimental data was achieved without applying any fitting procedure to the model parameters.

  10. Online Video-Based Training in the Use of Hydrologic Models: A Case Example Using SWAT

    NASA Astrophysics Data System (ADS)

    Frankenberger, J.

    2009-12-01

    , and posing questions to the web-based group. Although excellent model documentation is available (http://www.brc.tamus.edu/swat/), the extent to which users conduct careful study to ensure that their understanding goes beyond the superficial level is unknown. Online video-on-demand technology provides a way for users to learn consistent content while saving travel resources, and allows for training to fit into people’s schedule. Online videos were created to teach the basics of setting up the model, acquiring input data, parameterizing, calibrating and evaluating model results, and analyzing outputs, as well as model science, uncertainty, and appropriate use. Feedback was sought from the SWAT modeling community to determine typical backgrounds of model users and how the video training fits into the available means of learning SWAT. Evaluation is being undertaken to assess results. The processes used in developing and evaluating the online SWAT training could be applied to other computer models for which use among broader groups of people is increasing or has the potential to grow.

  11. CCTOP: a Consensus Constrained TOPology prediction web server.

    PubMed

    Dobson, László; Reményi, István; Tusnády, Gábor E

    2015-07-01

    The Consensus Constrained TOPology prediction (CCTOP; http://cctop.enzim.ttk.mta.hu) server is a web-based application providing transmembrane topology prediction. In addition to utilizing 10 different state-of-the-art topology prediction methods, the CCTOP server incorporates topology information from existing experimental and computational sources available in the PDBTM, TOPDB and TOPDOM databases using the probabilistic framework of hidden Markov model. The server provides the option to precede the topology prediction with signal peptide prediction and transmembrane-globular protein discrimination. The initial result can be recalculated by (de)selecting any of the prediction methods or mapped experiments or by adding user specified constraints. CCTOP showed superior performance to existing approaches. The reliability of each prediction is also calculated, which correlates with the accuracy of the per protein topology prediction. The prediction results and the collected experimental information are visualized on the CCTOP home page and can be downloaded in XML format. Programmable access of the CCTOP server is also available, and an example of client-side script is provided.

  12. Using the Knowledge, Process, Practice (KPP) model for driving the design and development of online postgraduate medical education.

    PubMed

    Shaw, Tim; Barnet, Stewart; Mcgregor, Deborah; Avery, Jennifer

    2015-01-01

    Online learning is a primary delivery method for continuing health education programs. It is critical that programs have curricula objectives linked to educational models that support learning. Using a proven educational modelling process ensures that curricula objectives are met and a solid basis for learning and assessment is achieved. To develop an educational design model that produces an educationally sound program development plan for use by anyone involved in online course development. We have described the development of a generic educational model designed for continuing health education programs. The Knowledge, Process, Practice (KPP) model is founded on recognised educational theory and online education practice. This paper presents a step-by-step guide on using this model for program development that encases reliable learning and evaluation. The model supports a three-step approach, KPP, based on learning outcomes and supporting appropriate assessment activities. It provides a program structure for online or blended learning that is explicit, educationally defensible, and supports multiple assessment points for health professionals. The KPP model is based on best practice educational design using a structure that can be adapted for a variety of online or flexibly delivered postgraduate medical education programs.

  13. Online model-based diagnosis to support autonomous operation of an advanced life support system

    NASA Technical Reports Server (NTRS)

    Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif

    2004-01-01

    This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.

  14. Online Dectection and Modeling of Safety Boundaries for Aerospace Application Using Bayesian Statistics

    NASA Technical Reports Server (NTRS)

    He, Yuning

    2015-01-01

    The behavior of complex aerospace systems is governed by numerous parameters. For safety analysis it is important to understand how the system behaves with respect to these parameter values. In particular, understanding the boundaries between safe and unsafe regions is of major importance. In this paper, we describe a hierarchical Bayesian statistical modeling approach for the online detection and characterization of such boundaries. Our method for classification with active learning uses a particle filter-based model and a boundary-aware metric for best performance. From a library of candidate shapes incorporated with domain expert knowledge, the location and parameters of the boundaries are estimated using advanced Bayesian modeling techniques. The results of our boundary analysis are then provided in a form understandable by the domain expert. We illustrate our approach using a simulation model of a NASA neuro-adaptive flight control system, as well as a system for the detection of separation violations in the terminal airspace.

  15. Online model-based diagnosis to support autonomous operation of an advanced life support system

    NASA Technical Reports Server (NTRS)

    Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif

    2004-01-01

    This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.

  16. Approximation modeling for the online performance management of distributed computing systems.

    PubMed

    Kusic, Dara; Kandasamy, Nagarajan; Jiang, Guofei

    2008-10-01

    A promising method of automating management tasks in computing systems is to formulate them as control or optimization problems in terms of performance metrics. For an online optimization scheme to be of practical value in a distributed setting, however, it must successfully tackle the curses of dimensionality and modeling. This paper develops a hierarchical control framework to solve performance management problems in distributed computing systems operating in a data center. Concepts from approximation theory are used to reduce the computational burden of controlling such large-scale systems. The relevant approximations are made in the construction of the dynamical models to predict system behavior and in the solution of the associated control equations. Using a dynamic resource-provisioning problem as a case study, we show that a computing system managed by the proposed control framework with approximation models realizes profit gains that are, in the best case, within 1% of a controller using an explicit model of the system.

  17. T-S model based indirect adaptive fuzzy control using online parameter estimation.

    PubMed

    Park, Chang-Woo; Cho, Young-Wan

    2004-12-01

    A parameter estimation scheme with an appropriate adaptive law for updating the parameters is designed and analyzed based on the Lyapunov theory for the general MIMO Takagi-Sugeno (T-S) fuzzy models. The parameters of the Takagi-Sugeno fuzzy models can be estimated by observing the behavior of the system and with the online parameter estimator, any type of fuzzy controllers works adaptively to the parameter perturbation. In order to show the applicability of the proposed estimator, an existing fuzzy state feedback controller is adopted and indirect adaptive fuzzy control design with the proposed estimator is shown. From the numerical simulations and experiments, it is shown that the derived adaptive law works for the estimation model to follows the parameterized plant model and the overall control system has robustness to the parameter perturbation.

  18. A Supervised Learning Process to Validate Online Disease Reports for Use in Predictive Models.

    PubMed

    Patching, Helena M M; Hudson, Laurence M; Cooke, Warrick; Garcia, Andres J; Hay, Simon I; Roberts, Mark; Moyes, Catherine L

    2015-12-01

    Pathogen distribution models that predict spatial variation in disease occurrence require data from a large number of geographic locations to generate disease risk maps. Traditionally, this process has used data from public health reporting systems; however, using online reports of new infections could speed up the process dramatically. Data from both public health systems and online sources must be validated before they can be used, but no mechanisms exist to validate data from online media reports. We have developed a supervised learning process to validate geolocated disease outbreak data in a timely manner. The process uses three input features, the data source and two metrics derived from the location of each disease occurrence. The location of disease occurrence provides information on the probability of disease occurrence at that location based on environmental and socioeconomic factors and the distance within or outside the current known disease extent. The process also uses validation scores, generated by disease experts who review a subset of the data, to build a training data set. The aim of the supervised learning process is to generate validation scores that can be used as weights going into the pathogen distribution model. After analyzing the three input features and testing the performance of alternative processes, we selected a cascade of ensembles comprising logistic regressors. Parameter values for the training data subset size, number of predictors, and number of layers in the cascade were tested before the process was deployed. The final configuration was tested using data for two contrasting diseases (dengue and cholera), and 66%-79% of data points were assigned a validation score. The remaining data points are scored by the experts, and the results inform the training data set for the next set of predictors, as well as going to the pathogen distribution model. The new supervised learning process has been implemented within our live site and is

  19. A Web Server for MACCS Magnetometer Data

    NASA Technical Reports Server (NTRS)

    Engebretson, Mark J.

    1998-01-01

    NASA Grant NAG5-3719 was provided to Augsburg College to support the development of a web server for the Magnetometer Array for Cusp and Cleft Studies (MACCS), a two-dimensional array of fluxgate magnetometers located at cusp latitudes in Arctic Canada. MACCS was developed as part of the National Science Foundation's GEM (Geospace Environment Modeling) Program, which was designed in part to complement NASA's Global Geospace Science programs during the decade of the 1990s. This report describes the successful use of these grant funds to support a working web page that provides both daily plots and file access to any user accessing the worldwide web. The MACCS home page can be accessed at http://space.augsburg.edu/space/MaccsHome.html.

  20. Quadfinder: server for identification and analysis of quadruplex-forming motifs in nucleotide sequences

    PubMed Central

    Scaria, Vinod; Hariharan, Manoj; Arora, Amit; Maiti, Souvik

    2006-01-01

    G-quadruplex secondary structures, which play a structural role in repetitive DNA such as telomeres, may also play a functional role at other genomic locations as targetable regulatory elements which control gene expression. The recent interest in application of quadruplexes in biological systems prompted us to develop a tool for the identification and analysis of quadruplex-forming nucleotide sequences especially in the RNA. Here we present Quadfinder, an online server for prediction and bioinformatics of uni-molecular quadruplex-forming nucleotide sequences. The server is designed to be user-friendly and needs minimal intervention by the user, while providing flexibility of defining the variants of the motif. The server is freely available at URL . PMID:16845097

  1. Biological SOAP servers and web services provided by the public sequence data bank

    PubMed Central

    Sugawara, H.; Miyazaki, S.

    2003-01-01

    A number of biological data resources (i.e. databases and data analytical tools) are searchable and usable on-line thanks to the internet and the World Wide Web (WWW) servers. The output from the web server is easy for us to browse. However, it is laborious and sometimes impossible for us to write a computer program that finds a useful data resource, sends a proper query and processes the output. It is a serious obstacle to the integration of distributed heterogeneous data resources. To solve the issue, we have implemented a SOAP (Simple Object Access Protocol) server and web services that provide a program-friendly interface. The web services are accessible at http://www.xml.nig.ac.jp/. PMID:12824432

  2. Methodology to model the energy and greenhouse gas emissions of electronic software distributions.

    PubMed

    Williams, Daniel R; Tang, Yinshan

    2012-01-17

    A new electronic software distribution (ESD) life cycle analysis (LCA) methodology and model structure were constructed to calculate energy consumption and greenhouse gas (GHG) emissions. In order to counteract the use of high level, top-down modeling efforts, and to increase result accuracy, a focus upon device details and data routes was taken. In order to compare ESD to a relevant physical distribution alternative, physical model boundaries and variables were described. The methodology was compiled from the analysis and operational data of a major online store which provides ESD and physical distribution options. The ESD method included the calculation of power consumption of data center server and networking devices. An in-depth method to calculate server efficiency and utilization was also included to account for virtualization and server efficiency features. Internet transfer power consumption was analyzed taking into account the number of data hops and networking devices used. The power consumed by online browsing and downloading was also factored into the model. The embedded CO(2)e of server and networking devices was proportioned to each ESD process. Three U.K.-based ESD scenarios were analyzed using the model which revealed potential CO(2)e savings of 83% when ESD was used over physical distribution. Results also highlighted the importance of server efficiency and utilization methods.

  3. Development of the acquisition model of online information resources at Faculty of Medicine Library, Khon Kaen University.

    PubMed

    Thanapaisal, Soodjai; Thanapaisal, Chaiwit

    2013-09-01

    Faculty of Medicine Library, Khon Kaen University started to acquire online information resources since 2001 with the subscriptions to 2 databases. Nowadays it has 29 items of subscriptions and the expenses on online information resources reach to 17 million baht, more than 70 percent of the information resources budget, serving the academic purposes of the Faculty of Medicine. The problems of online information resources acquisition fall into 4 categories, and lead to 4 aspects conforming the model of the acquisition, comparing or benchmarking with the 4 selected medical school libraries in Bangkok, Chiang Mai, and Songkhla, and discussion with some other Thai and foreign libraries. The acquisition model of online information resources is developed from those problems and proposed for Faculty of Medicine Library, Khon Kaen University as well as for any medical libraries which prefer.

  4. An online spatio-temporal prediction model for dengue fever epidemic in Kaohsiung,Taiwan

    NASA Astrophysics Data System (ADS)

    Cheng, Ming-Hung; Yu, Hwa-Lung; Angulo, Jose; Christakos, George

    2013-04-01

    Dengue Fever (DF) is one of the most serious vector-borne infectious diseases in tropical and subtropical areas. DF epidemics occur in Taiwan annually especially during summer and fall seasons. Kaohsiung city has been one of the major DF hotspots in decades. The emergence and re-emergence of the DF epidemic is complex and can be influenced by various factors including space-time dynamics of human and vector populations and virus serotypes as well as the associated uncertainties. This study integrates a stochastic space-time "Susceptible-Infected-Recovered" model under Bayesian maximum entropy framework (BME-SIR) to perform real-time prediction of disease diffusion across space-time. The proposed model is applied for spatiotemporal prediction of the DF epidemic at Kaohsiung city during 2002 when the historical series of high DF cases was recorded. The online prediction by BME-SIR model updates the parameters of SIR model and infected cases across districts over time. Results show that the proposed model is rigorous to initial guess of unknown model parameters, i.e. transmission and recovery rates, which can depend upon the virus serotypes and various human interventions. This study shows that spatial diffusion can be well characterized by BME-SIR model, especially at the district surrounding the disease outbreak locations. The prediction performance at DF hotspots, i.e. Cianjhen and Sanmin, can be degraded due to the implementation of various disease control strategies during the epidemics. The proposed online disease prediction BME-SIR model can provide the governmental agency with a valuable reference to timely identify, control, and efficiently prevent DF spread across space-time.

  5. Online estimation of respiratory mechanics in non-invasive pressure support ventilation: a bench model study.

    PubMed

    Mulqueeny, Qestra; Tassaux, Didier; Vignaux, Laurence; Jolliet, Philippe; Schindhelm, Klaus; Redmond, Stephen; Lovell, Nigel H

    2010-01-01

    An online algorithm for determining respiratory mechanics in patients using non-invasive ventilation (NIV) in pressure support mode was developed and embedded in a ventilator system. Based on multiple linear regression (MLR) of respiratory data, the algorithm was tested on a patient bench model under conditions with and without leak and simulating a variety of mechanics. Bland-Altman analysis indicates reliable measures of compliance across the clinical range of interest (± 11-18% limits of agreement). Resistance measures showed large quantitative errors (30-50%), however, it was still possible to qualitatively distinguish between normal and obstructive resistances. This outcome provides clinically significant information for ventilator titration and patient management.

  6. VizieR Online Data Catalog: Grid of solar-metallicity wind models (Mattsson+, 2010)

    NASA Astrophysics Data System (ADS)

    Mattsson, L.; Wahlin, R.; Hoefner, S.

    2010-06-01

    The file online.dat contains all the data presented in the paper. The table include input parameters and the resulting mean mass loss rate, mean velocity at the outer boundary and mean degree of dust condensation at the outer boundary. The dust-to-gas mass ratio is calculated as described in Hofner & Dorfi (1997A&A...319..648H). A FORTRAN code representing a parametric mass-loss prescription for, e.g., stellar evolution modelling, is available at http://coolstars.astro.uu.se where also future updates will be posted. (1 data file).

  7. Real time hybrid simulation with online model updating: An analysis of accuracy

    NASA Astrophysics Data System (ADS)

    Ou, Ge; Dyke, Shirley J.; Prakash, Arun

    2017-02-01

    In conventional hybrid simulation (HS) and real time hybrid simulation (RTHS) applications, the information exchanged between the experimental substructure and numerical substructure is typically restricted to the interface boundary conditions (force, displacement, acceleration, etc.). With additional demands being placed on RTHS and recent advances in recursive system identification techniques, an opportunity arises to improve the fidelity by extracting information from the experimental substructure. Online model updating algorithms enable the numerical model of components (herein named the target model), that are similar to the physical specimen to be modified accordingly. This manuscript demonstrates the power of integrating a model updating algorithm into RTHS (RTHSMU) and explores the possible challenges of this approach through a practical simulation. Two Bouc-Wen models with varying levels of complexity are used as target models to validate the concept and evaluate the performance of this approach. The constrained unscented Kalman filter (CUKF) is selected for using in the model updating algorithm. The accuracy of RTHSMU is evaluated through an estimation output error indicator, a model updating output error indicator, and a system identification error indicator. The results illustrate that, under applicable constraints, by integrating model updating into RTHS, the global response accuracy can be improved when the target model is unknown. A discussion on model updating parameter sensitivity to updating accuracy is also presented to provide guidance for potential users.

  8. Surfing for Data: A Gathering Trend in Data Storage Is the Use of Web-Based Applications that Make It Easy for Authorized Users to Access Hosted Server Content with Just a Computing Device and Browser

    ERIC Educational Resources Information Center

    Technology & Learning, 2005

    2005-01-01

    In recent years, the widespread availability of networks and the flexibility of Web browsers have shifted the industry from a client-server model to a Web-based one. In the client-server model of computing, clients run applications locally, with the servers managing storage, printing functions, and network traffic. Because every client is…

  9. Assessment of Energy Removal Impacts on Physical Systems: Hydrodynamic Model Domain Expansion and Refinement, and Online Dissemination of Model Results

    SciTech Connect

    Yang, Zhaoqing; Khangaonkar, Tarang; Wang, Taiping

    2010-08-01

    In this report we describe the 1) the expansion of the PNNL hydrodynamic model domain to include the continental shelf along the coasts of Washington, Oregon, and Vancouver Island; and 2) the approach and progress in developing the online/Internet disseminations of model results and outreach efforts in support of the Puget Sound Operational Forecast System (PS-OPF). Submittal of this report completes the work on Task 2.1.2, Effects of Physical Systems, Subtask 2.1.2.1, Hydrodynamics, for fiscal year 2010 of the Environmental Effects of Marine and Hydrokinetic Energy project.

  10. You're a What? Process Server

    ERIC Educational Resources Information Center

    Torpey, Elka

    2012-01-01

    In this article, the author talks about the role and functions of a process server. The job of a process server is to hand deliver legal documents to the people involved in court cases. These legal documents range from a summons to appear in court to a subpoena for producing evidence. Process serving can involve risk, as some people take out their…

  11. Optimizing the NASA Technical Report Server.

    ERIC Educational Resources Information Center

    Nelson, Michael L.; Maa, Ming-Hokng

    1996-01-01

    Modifying the NASA Technical Report Server (NTRS), a World Wide Web report distribution NASA technical publications service, has enhanced its performance, protocol support, and human interfacing. This article discusses the original and revised NTRS architecture, sequential and parallel query methods, and wide area information server (WAIS) uniform…

  12. Get the Word Out with List Servers

    ERIC Educational Resources Information Center

    Goldberg, Laurence

    2006-01-01

    In this article, the author details the use of electronic mail server in their school. In their school district of about 7,300 students in suburban Philadelphia (Abington SD), electronic mail list servers are now being used, along with other methods of communication, to disseminate information quickly and widely. They began by manually maintaining…

  13. Server-Side Includes Made Simple.

    ERIC Educational Resources Information Center

    Fagan, Jody Condit

    2002-01-01

    Describes server-side include (SSI) codes which allow Webmasters to insert content into Web pages without programming knowledge. Explains how to enable the codes on a Web server, provides a step-by-step process for implementing them, discusses tags and syntax errors, and includes examples of their use on the Web site for Southern Illinois…

  14. Optimizing the NASA Technical Report Server.

    ERIC Educational Resources Information Center

    Nelson, Michael L.; Maa, Ming-Hokng

    1996-01-01

    Modifying the NASA Technical Report Server (NTRS), a World Wide Web report distribution NASA technical publications service, has enhanced its performance, protocol support, and human interfacing. This article discusses the original and revised NTRS architecture, sequential and parallel query methods, and wide area information server (WAIS) uniform…

  15. HDF-EOS Web Server

    NASA Technical Reports Server (NTRS)

    Ullman, Richard; Bane, Bob; Yang, Jingli

    2008-01-01

    A shell script has been written as a means of automatically making HDF-EOS-formatted data sets available via the World Wide Web. ("HDF-EOS" and variants thereof are defined in the first of the two immediately preceding articles.) The shell script chains together some software tools developed by the Data Usability Group at Goddard Space Flight Center to perform the following actions: Extract metadata in Object Definition Language (ODL) from an HDF-EOS file, Convert the metadata from ODL to Extensible Markup Language (XML), Reformat the XML metadata into human-readable Hypertext Markup Language (HTML), Publish the HTML metadata and the original HDF-EOS file to a Web server and an Open-source Project for a Network Data Access Protocol (OPeN-DAP) server computer, and Reformat the XML metadata and submit the resulting file to the EOS Clearinghouse, which is a Web-based metadata clearinghouse that facilitates searching for, and exchange of, Earth-Science data.

  16. The NASA Technical Report Server

    NASA Technical Reports Server (NTRS)

    Nelson, Michael L.; Gottlich, Gretchen L.; Bianco, David J.; Paulson, Sharon S.; Binkley, Robert L.; Kellogg, Yvonne D.; Beaumont, Chris J.; Schmunk, Robert B.; Kurtz, Michael J.; Accomazzi, Alberto

    1995-01-01

    The National Aeronautics and Space Act of 1958 established NASA and charged it to "provide for the widest practicable and appropriate dissemination of information concerning its activities and the results thereof." The search for innovative methods to distribute NASA's information lead a grass-roots team to create the NASA Technical Report Server (NTRS), which uses the World Wide Web and other popular Internet-based information systems as search engines. The NTRS is an inter-center effort which provides uniform access to various distributed publication servers residing on the Internet. Users have immediate desktop access to technical publications from NASA centers and institutes. The NTRS is comprised of several units, some constructed especially for inclusion in NTRS, and others that are existing NASA publication services that NTRS reuses. This paper presents the NTRS architecture, usage metrics, and the lessons learned while implementing and maintaining the service. The NTRS is largely constructed with freely available software running on existing hardware. NTRS builds upon existing hardware and software, and the resulting additional exposure for the body of literature contained ensures that NASA's institutional knowledge base will continue to receive the widest practicable and appropriate dissemination.

  17. mMWeb - An Online Platform for Employing Multiple Ecological Niche Modeling Algorithms

    PubMed Central

    Qiao, Huijie; Lin, Congtian; Ji, Liqiang; Jiang, Zhigang

    2012-01-01

    Background Predicting the ecological niche and potential habitat distribution of a given organism is one of the central domains of ecological and biogeographical research. A wide variety of modeling techniques have been developed for this purpose. In order to implement these models, the users must prepare a specific runtime environment for each model, learn how to use multiple model platforms, and prepare data in a different format each time. Additionally, often model results are difficult to interpret, and a standardized method for comparing model results across platforms does not exist. We developed a free and open source online platform, the multi-models web-based (mMWeb) platform, to address each of these problems, providing a novel environment in which the user can implement and compare multiple ecological niche model (ENM) algorithms. Methodology mMWeb combines 18 existing ENMs and their corresponding algorithms and provides a uniform procedure for modeling the potential habitat niche of a species via a common web browser. mMWeb uses Java Native Interface (JNI), Java R Interface to combine the different ENMs and executes multiple tasks in parallel on a super computer. The cross-platform, user-friendly interface of mMWeb simplifies the process of building ENMs, providing an accessible and efficient environment from which to explore and compare different model algorithms. PMID:22912854

  18. Online Simulations and Forecasts of the Global Aerosol Distribution in the NASA GEOS-5 Model

    NASA Technical Reports Server (NTRS)

    Colarco, Peter

    2006-01-01

    We present an analysis of simulations of the global aerosol system in the NASA GEOS-5 transport, radiation, and chemistry model. The model includes representations of all major tropospheric aerosol species, including dust, sea salt, black carbon, particulate organic matter, and sulfates. The aerosols are run online for the period 2000 through 2005 in a simulation driven by assimilated meteorology from the NASA Goddard Data Assimilation System. Aerosol surface mass concentrations are compared with existing long-term surface measurement networks. Aerosol optical thickness is compared with ground-based AERONET sun photometry and space-based retrievals from MODIS, MISR, and OMI. Particular emphasis is placed here on consistent sampling of model and satellite aerosol optical thickness to account for diurnal variations in aerosol optical properties. Additionally, we illustrate the use of this system for providing chemical weather forecasts in support of various NASA and community field missions.

  19. Online Simulations and Forecasts of the Global Aerosol Distribution in the NASA GEOS-5 Model

    NASA Technical Reports Server (NTRS)

    Colarco, Peter

    2006-01-01

    We present an analysis of simulations of the global aerosol system in the NASA GEOS-5 transport, radiation, and chemistry model. The model includes representations of all major tropospheric aerosol species, including dust, sea salt, black carbon, particulate organic matter, and sulfates. The aerosols are run online for the period 2000 through 2005 in a simulation driven by assimilated meteorology from the NASA Goddard Data Assimilation System. Aerosol surface mass concentrations are compared with existing long-term surface measurement networks. Aerosol optical thickness is compared with ground-based AERONET sun photometry and space-based retrievals from MODIS, MISR, and OMI. Particular emphasis is placed here on consistent sampling of model and satellite aerosol optical thickness to account for diurnal variations in aerosol optical properties. Additionally, we illustrate the use of this system for providing chemical weather forecasts in support of various NASA and community field missions.

  20. On-line updating of a distributed flow routing model - River Vistula case study

    NASA Astrophysics Data System (ADS)

    Karamuz, Emilia; Romanowicz, Renata; Napiorkowski, Jaroslaw

    2015-04-01

    This paper presents an application of methods of on-line updating in the River Vistula flow forecasting system. All flow-routing codes make simplifying assumptions and consider only a reduced set of the processes known to occur during a flood. Hence, all models are subject to a degree of structural error that is typically compensated for by calibration of the friction parameters. Calibrated parameter values are not, therefore, physically realistic, as in estimating them we also make allowance for a number of distinctly non-physical effects, such as model structural error and any energy losses or flow processes which occur at sub-grid scales. Calibrated model parameters are therefore area-effective, scale-dependent values which are not drawn from the same underlying statistical distribution as the equivalent at-a-point parameter of the same name. The aim of this paper is the derivation of real-time updated, on-line flow forecasts at certain strategic locations along the river, over a specified time horizon into the future, based on information on the behaviour of the flood wave upstream and available on-line measurements at a site. Depending on the length of the river reach and the slope of the river bed, a realistic forecast lead time, obtained in this manner, may range from hours to days. The information upstream can include observations of river levels and/or rainfall measurements. The proposed forecasting system will integrate distributed modelling, acting as a spatial interpolator with lumped parameter Stochastic Transfer Function models. Daily stage data from gauging stations are typically available at sites 10-60 km apart and test only the average routing performance of hydraulic models and not their ability to produce spatial predictions. Application of a distributed flow routing model makes it possible to interpolate forecasts both in time and space. This work was partly supported by the project "Stochastic flood forecasting system (The River Vistula reach

  1. Multivariate detection limits of on-line NIR model for extraction process of chlorogenic acid from Lonicera japonica.

    PubMed

    Wu, Zhisheng; Sui, Chenglin; Xu, Bing; Ai, Lu; Ma, Qun; Shi, Xinyuan; Qiao, Yanjiang

    2013-04-15

    A methodology is proposed to estimate the multivariate detection limits (MDL) of on-line near-infrared (NIR) model in Chinese Herbal Medicines (CHM) system. In this paper, Lonicera japonica was used as an example, and its extraction process was monitored by on-line NIR spectroscopy. Spectra of on-line NIR could be collected by two fiber optic probes designed to transmit NIR radiation by a 2mm-flange. High performance liquid chromatography (HPLC) was used as a reference method to determine the content of chlorogenic acid in the extract solution. Multivariate calibration models were carried out including partial least squares regression (PLS) and interval partial least-squares (iPLS). The result showed improvement of model performance: compared with PLS model, the root mean square errors of prediction (RMSEP) of iPLS model decreased from 0.111mg to 0.068mg, and the R(2) parameter increased from 0.9434 to 0.9801. Furthermore, MDL values were determined by a multivariate method using the type of errors and concentration ranges. The MDL of iPLS model was about 14ppm, which confirmed that on-line NIR spectroscopy had the ability to detect trace amounts of chlorogenic acid in L. japonica. As a result, the application of on-line NIR spectroscopy for monitoring extraction process in CHM could be very encouraging and reliable.

  2. Online identification of the ARX model expansion on Laguerre orthonormal bases with filters on model input and output

    NASA Astrophysics Data System (ADS)

    Bouzrara, Kais; Garna, Tarek; Ragot, José; Messaoud, Hassani

    2013-03-01

    This article proposes a new representation of the ARX models on independent and orthonormal Laguerre bases by filtering the process input and output using Laguerre orthonormal functions. The resulting model, entitled ARX-Laguerre model, ensures the parameter number reduction with a recursive and easy representation. However, this reduction is still subject to an optimal choice of the Laguerre poles defining both Laguerre bases. Therefore, we propose an analytical solution to optimise the Laguerre poles which depend on Fourier coefficients defining the ARX-Laguerre model, and that are identified using the regularised square error. The identification procedures of the Laguerre poles and Fourier coefficients are combined and carried out on a sliding window to provide an online identification algorithm of the ARX-Laguerre model. The proposed algorithm is tested on numerical simulation and validated on a benchmark system manufactured by Feedback known as Process Trainer PT326.

  3. Reconstructing paleoclimate fields using online data assimilation with a linear inverse model

    NASA Astrophysics Data System (ADS)

    Perkins, Walter A.; Hakim, Gregory J.

    2017-05-01

    We examine the skill of a new approach to climate field reconstructions (CFRs) using an online paleoclimate data assimilation (PDA) method. Several recent studies have foregone climate model forecasts during assimilation due to the computational expense of running coupled global climate models (CGCMs) and the relatively low skill of these forecasts on longer timescales. Here we greatly diminish the computational cost by employing an empirical forecast model (linear inverse model, LIM), which has been shown to have skill comparable to CGCMs for forecasting annual-to-decadal surface temperature anomalies. We reconstruct annual-average 2 m air temperature over the instrumental period (1850-2000) using proxy records from the PAGES 2k Consortium Phase 1 database; proxy models for estimating proxy observations are calibrated on GISTEMP surface temperature analyses. We compare results for LIMs calibrated using observational (Berkeley Earth), reanalysis (20th Century Reanalysis), and CMIP5 climate model (CCSM4 and MPI) data relative to a control offline reconstruction method. Generally, we find that the usage of LIM forecasts for online PDA increases reconstruction agreement with the instrumental record for both spatial fields and global mean temperature (GMT). Specifically, the coefficient of efficiency (CE) skill metric for detrended GMT increases by an average of 57 % over the offline benchmark. LIM experiments display a common pattern of skill improvement in the spatial fields over Northern Hemisphere land areas and in the high-latitude North Atlantic-Barents Sea corridor. Experiments for non-CGCM-calibrated LIMs reveal region-specific reductions in spatial skill compared to the offline control, likely due to aspects of the LIM calibration process. Overall, the CGCM-calibrated LIMs have the best performance when considering both spatial fields and GMT. A comparison with the persistence forecast experiment suggests that improvements are associated with the linear

  4. Parameter Identification and On-line Estimation of a Reduced Kinetic Model

    SciTech Connect

    Dellorco, P.C.; Flesner, R.L.; Le, L.A.; Littell, J.D.; Muske, K.R.

    1999-02-01

    In this work, we present the estimation techniques used to update the model parameters in a reduced kinetic model describing the oxidation-reduction re- actions in a hydrothermal oxidation reactor. The model is used in a nonlinear model-based controller that minimizes the total aqueous nitrogen in the reac- tor effluent. Model reduction is accomplished by com- bining similar reacting compounds into one of four component groups and considering the global reac- tion pathways for each of these groups. The reduced kinetic model developed for thk reaction system pro- vides a means to characterize the complex chemical reaction system without considering each chemicaJ species present and the reaction kinetics of every pos- sible reaction pathway. For the reaction system under study, model reduction is essential in order to reduce the computational requirement so that on-line imple- mentation of the nonlinear model-based controller is possible and also to reduce the amount of a priori information required for the model.

  5. Using Online Space Weather Modeling Resources in a Capstone Undergraduate Course

    NASA Astrophysics Data System (ADS)

    Liemohn, M.

    2012-04-01

    The University of Michigan offers a senior-undergraduate-level course entitled, "Space Weather Modeling," taken by all of the space weather concentration students in the Atmospheric, Oceanic, and Space Sciences department. This is the capstone course of our undergraduate series, using the foundational knowledge from the previous courses towards an integrative large-scale numerical modeling study. A fraction of the graduate students also take this course. Because the state-of-the-art modeling capabilities are well beyond what is possible in a single term of programming, this course uses available online model resources, in particular the Community Coordinated Modeling Center (CCMC), a multi-agency facility hosted by NASA's Goddard Space Flight Center. Students learn not only how to use the codes, but also the various options of what equations to solve to model a specific region of space and the various numerical approaches for implementing the equations within a code. The course is project-based, consisting of multiple written reports and oral presentations, and the technical communication skills are an important component of the grading rubric. Students learn how to conduct a numerical modeling study by critiquing several space weather modeling journal articles, and then carry out their our studies with several of the available codes. In the end, they are familiarized with the available models to know the ranges of validity and applicability for a wide array of space weather applications.

  6. Online Plasma Shape Reconstruction for EAST Tokamak

    NASA Astrophysics Data System (ADS)

    Luo, Zhengping; Xiao, Bingjia; Zhu, Yingfei; Yang, Fei

    2010-08-01

    An online plasma shape reconstruction, based on the offline version of the EFIT code and MPI library, can be carried out between two adjacent shots in EAST. It combines online data acquisition, parallel calculation, and data storage together. The program on the master node of the cluster detects the termination of the discharge promptly, reads diagnostic data from the EAST mdsplus server on the completion of data storing, and writes the results onto the EFIT mdsplus server after the calculation is finished. These processes run automatically on a nine-nodes IBM blade center. The total time elapsed is about 1 second to several minutes, depending on the duration of the shot. With the results stored in the mdsplus server, it is convenient for operators and physicists to analyze the behavior of plasma using visualization tools.

  7. Migrating an Online Service to WAP - A Case Study.

    ERIC Educational Resources Information Center

    Klasen, Lars

    2002-01-01

    Discusses mobile access via wireless application protocol (WAP) to online services that is offered in Sweden through InfoTorg. Topics include the Swedish online market; filtering HTML data from an Internet/Web server into WML (wireless markup language); mobile phone technology; microbrowsers; WAP protocol; and future possibilities. (LRW)

  8. Migrating an Online Service to WAP - A Case Study.

    ERIC Educational Resources Information Center

    Klasen, Lars

    2002-01-01

    Discusses mobile access via wireless application protocol (WAP) to online services that is offered in Sweden through InfoTorg. Topics include the Swedish online market; filtering HTML data from an Internet/Web server into WML (wireless markup language); mobile phone technology; microbrowsers; WAP protocol; and future possibilities. (LRW)

  9. The Impact of Inherent Instructional Design in Online Courseware.

    ERIC Educational Resources Information Center

    Harvey, Douglas M.; Lee, Jung

    2001-01-01

    Examines how the use of server-based courseware development solutions affects the instructional design process when creating online distance education. Highlights include pedagogical, visual interface (e.g., visual metaphor and navigation layout), interaction, and instructional design implications of online courseware. (Contains 54 references.)…

  10. Top U.S. Sources for an Online Job Search.

    ERIC Educational Resources Information Center

    Dolan, Donna R.; Schumacher, John E.

    1994-01-01

    Discusses how to look for jobs via the Internet and online databases. Highlights include Internet sources for job information, including lists, gopher servers, online "Chronicle of Higher Education," College-Wide Information Systems (CWIS), and "America's Job Bank"; options without Internet access; where to list a resume; and…

  11. Top U.S. Sources for an Online Job Search.

    ERIC Educational Resources Information Center

    Dolan, Donna R.; Schumacher, John E.

    1994-01-01

    Discusses how to look for jobs via the Internet and online databases. Highlights include Internet sources for job information, including lists, gopher servers, online "Chronicle of Higher Education," College-Wide Information Systems (CWIS), and "America's Job Bank"; options without Internet access; where to list a resume; and…

  12. Differential surface models for tactile perception of shape and on-line tracking of features

    NASA Technical Reports Server (NTRS)

    Hemami, H.

    1987-01-01

    Tactile perception of shape involves an on-line controller and a shape perceptor. The purpose of the on-line controller is to maintain gliding or rolling contact with the surface, and collect information, or track specific features of the surface such as edges of a certain sharpness. The shape perceptor uses the information to perceive, estimate the parameters of, or recognize the shape. The differential surface model depends on the information collected and on the a priori information known about the robot and its physical parameters. These differential models are certain functionals that are projections of the dynamics of the robot onto the surface gradient or onto the tangent plane. A number of differential properties may be directly measured from present day tactile sensors. Others may have to be indirectly computed from measurements. Others may constitute design objectives for distributed tactile sensors of the future. A parameterization of the surface leads to linear and nonlinear sequential parameter estimation techniques for identification of the surface. Many interesting compromises between measurement and computation are possible.

  13. Use of Online Forums for Perinatal Mental Illness, Stigma, and Disclosure: An Exploratory Model

    PubMed Central

    Drey, Nicholas; Ayers, Susan

    2017-01-01

    Background Perinatal mental illness is a global health concern; however, many women with the illness do not get the treatment they need to recover. Interventions that reduce the stigma around perinatal mental illness have the potential to enable women to disclose their symptoms to health care providers and consequently access treatment. There are many online forums for perinatal mental illness and thousands of women use them. Preliminary research suggests that online forums may promote help-seeking behavior, potentially because they have a role in challenging stigma. This study draws from these findings and theoretical concepts to present a model of forum use, stigma, and disclosure. Objective This study tested a model that measured the mediating role of stigma between online forum use and disclosure of affective symptoms to health care providers. Methods A Web-based survey of 200 women who were pregnant or had a child younger than 5 years and considered themselves to be experiencing psychological distress was conducted. Women were recruited through social media and questions measured forum usage, perinatal mental illness stigma, disclosure to health care providers, depression and anxiety symptoms, barriers to disclosure, and demographic information. Results There was a significant positive indirect effect of length of forum use on disclosure of symptoms through internal stigma, b=0.40, bias-corrected and accelerated (BCa) 95% CI 0.13-0.85. Long-term forum users reported higher levels of internal stigma, and higher internal stigma was associated with disclosure of symptoms to health care providers when controlling for symptoms of depression and anxiety. Conclusions Internal stigma mediates the relationship between length of forum use and disclosure to health care providers. Findings suggest that forums have the potential to enable women to recognize and reveal their internal stigma, which may in turn lead to greater disclosure of symptoms to health care providers

  14. Modeling of The hERG K+ Channel Blockage Using Online Chemical Database and Modeling Environment (OCHEM).

    PubMed

    Li, Xiao; Zhang, Yuan; Li, Huanhuan; Zhao, Yong

    2017-08-30

    Human ether-a-go-go related gene (hERG) K+ channel plays an important role in cardiac action potential. Blockage of hERG channel may result in long QT syndrome (LQTS), even cause sudden cardiac death. Many drugs have been withdrawn from the market because of the serious hERG-related cardiotoxicity. Therefore, it is quite essential to estimate the chemical blockage of hERG in the early stage of drug discovery. In this study, a diverse set of 3721 compounds with hERG inhibition data was assembled from literature. Then, we make full use of the Online Chemical Modeling Environment (OCHEM), which supplies rich machine learning methods and descriptor sets, to build a series of classification models for hERG blockage. We also generated two consensus models based on the top-performing individual models. The consensus models performed much better than the individual models both on 5-fold cross validation and external validation. Especially, consensus model II yielded the prediction accuracy of 89.5 % and MCC of 0.670 on external validation. This result indicated that the predictive power of consensus model II should be stronger than most of the previously reported models. The 17 top-performing individual models and the consensus models and the data sets used for model development are available at https://ochem.eu/article/103592. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Modeling and Analysis Methods for an On-line Enrichment Monitor

    SciTech Connect

    Smith, Leon E.; Jarman, Kenneth D.; Wittman, Richard S.; Zalavadia, Mital A.; March-Leuba, Jose A.

    2016-05-30

    The International Atomic Energy Agency (IAEA) has developed an On-Line Enrichment Monitor (OLEM) as one possible component in a new generation of safeguards measures for uranium enrichment plants. The OLEM measures 235U emissions from the UF6 gas flowing through a unit header pipe using NaI(Tl) spectrometers, and corrects for gas density changes using pressure and temperature sensors in order to determine the enrichment of the gas as a function of time. In parallel with the OLEM instrument development, a Virtual OLEM (VOLEM) software tool has been developed that is capable of producing synthetic gamma-ray, pressure, and temperature data representative of a wide range of enrichment plant operating conditions. VOLEM complements instrument development activities and allows the study of OLEM for scenarios that will be difficult or impossible to evaluate empirically. Uses of VOLEM include: investigation of hardware design options; inter-comparison of candidate gamma-ray spectral analysis and enrichment estimation algorithms; uncertainty budget analysis and performance prediction for typical and atypical operational scenarios; and testing of the OLEM data acquisition, analysis and reporting software. This paper describes the technical foundations of VOLEM and illustrates how it can be used. An overview of the nominal instrument design and deployment scenario for OLEM is provided, with emphasis on the key online-assay measurement challenge: accurately determining the portion of the total 235U signal that comes from a background that includes solid uranium deposits on the piping walls. Monte Carlo modeling tools, data analysis algorithms and uncertainty quantification methods are described. VOLEM is then used to quantitatively explore the uncertainty budgets and predicted instrument performance for a plausible range of typical plant operating parameters, and one set of candidate analysis algorithms. Additionally, a series of VOLEM case studies illustrates how an online

  16. Volcanic ash modeling with the online NMMB-MONARCH-ASH v1.0 model: model description, case simulation, and evaluation

    NASA Astrophysics Data System (ADS)

    Marti, Alejandro; Folch, Arnau; Jorba, Oriol; Janjic, Zavisa

    2017-03-01

    Traditionally, tephra transport and dispersal models have evolved decoupled (offline) from numerical weather prediction models. There is a concern that inconsistencies and shortcomings associated with this coupling strategy might lead to errors in the ash cloud forecast. Despite this concern and the significant progress in improving the accuracy of tephra dispersal models in the aftermath of the 2010 Eyjafjallajökull and 2011 Cordón Caulle eruptions, to date, no operational online dispersal model is available to forecast volcanic ash. Here, we describe and evaluate NMMB-MONARCH-ASH, a new online multi-scale meteorological and transport model that attempts to pioneer the forecast of volcanic aerosols at operational level. The model forecasts volcanic ash cloud trajectories, concentration of ash at relevant flight levels, and the expected deposit thickness for both regional and global configurations. Its online coupling approach improves the current state-of-the-art tephra dispersal models, especially in situations where meteorological conditions are changing rapidly in time, two-way feedbacks are significant, or distal ash cloud dispersal simulations are required. This work presents the model application for the first phases of the 2011 Cordón Caulle and 2001 Mount Etna eruptions. The computational efficiency of NMMB-MONARCH-ASH and its application results compare favorably with other long-range tephra dispersal models, supporting its operational implementation.

  17. HydroShare: An online, collaborative environment for the sharing of hydrologic data and models (Invited)

    NASA Astrophysics Data System (ADS)

    Tarboton, D. G.; Idaszak, R.; Horsburgh, J. S.; Ames, D.; Goodall, J. L.; Band, L. E.; Merwade, V.; Couch, A.; Arrigo, J.; Hooper, R. P.; Valentine, D. W.; Maidment, D. R.

    2013-12-01

    HydroShare is an online, collaborative system being developed for sharing hydrologic data and models. The goal of HydroShare is to enable scientists to easily discover and access data and models, retrieve them to their desktop or perform analyses in a distributed computing environment that may include grid, cloud or high performance computing model instances as necessary. Scientists may also publish outcomes (data, results or models) into HydroShare, using the system as a collaboration platform for sharing data, models and analyses. HydroShare is expanding the data sharing capability of the CUAHSI Hydrologic Information System by broadening the classes of data accommodated, creating new capability to share models and model components, and taking advantage of emerging social media functionality to enhance information about and collaboration around hydrologic data and models. One of the fundamental concepts in HydroShare is that of a Resource. All content is represented using a Resource Data Model that separates system and science metadata and has elements common to all resources as well as elements specific to the types of resources HydroShare will support. These will include different data types used in the hydrology community and models and workflows that require metadata on execution functionality. HydroShare will use the integrated Rule-Oriented Data System (iRODS) to manage federated data content and perform rule-based background actions on data and model resources, including parsing to generate metadata catalog information and the execution of models and workflows. This presentation will introduce the HydroShare functionality developed to date, describe key elements of the Resource Data Model and outline the roadmap for future development.

  18. Use of whole building simulation in on-line performance assessment: Modeling and implementation issues

    SciTech Connect

    Haves, Philip; Salsbury, Tim; Claridge, David; Liu, Mingsheng

    2001-06-15

    The application of model-based performance assessment at the whole building level is explored. The information requirements for a simulation to predict the actual performance of a particular real building, as opposed to estimating the impact of design options, are addressed with particular attention to common sources of input error and important deficiencies in most simulation models. The role of calibrated simulations is discussed. The communication requirements for passive monitoring and active testing are identified and the possibilities for using control system communications protocols to link on-line simulation and energy management and control systems are discussed. The potential of simulation programs to act as ''plug-and-play'' components on building control networks is discussed.

  19. A conceptual model for analysing informal learning in online social networks for health professionals.

    PubMed

    Li, Xin; Gray, Kathleen; Chang, Shanton; Elliott, Kristine; Barnett, Stephen

    2014-01-01

    Online social networking (OSN) provides a new way for health professionals to communicate, collaborate and share ideas with each other for informal learning on a massive scale. It has important implications for ongoing efforts to support Continuing Professional Development (CPD) in the health professions. However, the challenge of analysing the data generated in OSNs makes it difficult to understand whether and how they are useful for CPD. This paper presents a conceptual model for using mixed methods to study data from OSNs to examine the efficacy of OSN in supporting informal learning of health professionals. It is expected that using this model with the dataset generated in OSNs for informal learning will produce new and important insights into how well this innovation in CPD is serving professionals and the healthcare system.

  20. Online variational inference for state-space models with point-process observations.

    PubMed

    Mangion, Andrew Zammit; Yuan, Ke; Kadirkamanathan, Visakan; Niranjan, Mahesan; Sanguinetti, Guido

    2011-08-01

    We present a variational Bayesian (VB) approach for the state and parameter inference of a state-space model with point-process observations, a physiologically plausible model for signal processing of spike data. We also give the derivation of a variational smoother, as well as an efficient online filtering algorithm, which can also be used to track changes in physiological parameters. The methods are assessed on simulated data, and results are compared to expectation-maximization, as well as Monte Carlo estimation techniques, in order to evaluate the accuracy of the proposed approach. The VB filter is further assessed on a data set of taste-response neural cells, showing that the proposed approach can effectively capture dynamical changes in neural responses in real time.