Web accessibility and open source software.

Science.gov (United States)

Obrenović, Zeljko

2009-07-01

A Web browser provides a uniform user interface to different types of information. Making this interface universally accessible and more interactive is a long-term goal still far from being achieved. Universally accessible browsers require novel interaction modalities and additional functionalities, for which existing browsers tend to provide only partial solutions. Although functionality for Web accessibility can be found as open source and free software components, their reuse and integration is complex because they were developed in diverse implementation environments, following standards and conventions incompatible with the Web. To address these problems, we have started several activities that aim at exploiting the potential of open-source software for Web accessibility. The first of these activities is the development of Adaptable Multi-Interface COmmunicator (AMICO):WEB, an infrastructure that facilitates efficient reuse and integration of open source software components into the Web environment. The main contribution of AMICO:WEB is in enabling the syntactic and semantic interoperability between Web extension mechanisms and a variety of integration mechanisms used by open source and free software components. Its design is based on our experiences in solving practical problems where we have used open source components to improve accessibility of rich media Web applications. The second of our activities involves improving education, where we have used our platform to teach students how to build advanced accessibility solutions from diverse open-source software. We are also partially involved in the recently started Eclipse projects called Accessibility Tools Framework (ACTF), the aim of which is development of extensible infrastructure, upon which developers can build a variety of utilities that help to evaluate and enhance the accessibility of applications and content for people with disabilities. In this article we briefly report on these activities.

The design of video and remote analysis system for gamma spectrum based on LabVIEW

International Nuclear Information System (INIS)

Xu Hongkun; Fang Fang; Chen Wei

2009-01-01

For the protection of analyst in the measurement,as well as the facilitation of expert to realize the remote analysis, a solution of live video combined with internet access and control is proposed. DirectShow technology and the LabVIEW'S IDT (Internet Develop Toolkit) module are used, video and analysis pages of the gamma energy spectrum are integrated and published in the windows system by IIS (Internet Information Sever). We realize the analysis of gamma spectrum and remote operations by internet. At the same time, the system has a friendly interface and easily to be put into practice. It also has some reference value for the related radioactive measurement. (authors)

Beyond Section 508: The Spectrum of Legal Requirements for Accessible e-Government Web Sites in the United States

Science.gov (United States)

Jaeger, Paul T.

2004-01-01

In the United States, a number of federal laws establish requirements that electronic government (e-government) information and services be accessible to individuals with disabilities. These laws affect e-government Web sites at the federal, state, and local levels. To this point, research about the accessibility of e-government Web sites has…

A web-based nuclear simulator using RELAP5 and LabVIEW

International Nuclear Information System (INIS)

Kim, K.D.; Rizwan-uddin

2007-01-01

A web-based nuclear reactor simulator has been developed using the best-estimate nuclear system analysis code RELAP5 as its engine, and LabVIEW for graphical user interface and web-casting. Simulator retains the accuracy of the best-estimate code. Results are displayed in user friendly graphical format. Color-coded nominal values are displayed along with the current status of different variables in tab activated windows. Some variables of interest are also shown as a function of time. All graphical outputs are displayed in web browsers making the simulator's front end independent of the operating system. The interactive simulation feature allows the users to simulate specific reactor transients - such as LOCA, scram, etc. - using a single click. Simulator's graphical output can be web-casted and is thus available to anybody with access to the web. Moreover, if permitted, the simulator can be operated remotely from another site connected to the server via the World Wide Web

Nucleonica. Web-based software tools for simulation and analysis

International Nuclear Information System (INIS)

Magill, J.; Dreher, R.; Soti, Z.

2014-01-01

The authors present a description of the Nucleonica web-based portal for simulation and analysis for a wide range of commonly encountered nuclear science applications. Advantages of a web-based approach include availability wherever there is internet access, intuitive user-friendly interface, remote access to high-power computing resources, and continual maintenance, improvement, and addition of tools and techniques common to the nuclear science industry. A description of the nuclear data resources, and some applications is given.

Hopping control channel MAC protocol for opportunistic spectrum access networks

Institute of Scientific and Technical Information of China (English)

FU Jing-tuan; JI Hong; MAO Xu

2010-01-01

Opportunistic spectrum access （OSA） is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access （CHMA） protocol,we introduce a hopping control channel medium access control （MAC） protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users＇ occupancy of the channel,we use a primary user （PU） detection model to calculate the channel availability for unlicensed users＇ access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

Gamma ray spectrum analysis code: sigmas 1.0

International Nuclear Information System (INIS)

Siangsanan, P.; Dharmavanij, W.; Chongkum, S.

1996-01-01

We have developed Sigmas 1.0 a software package for data reduction and gamma ray spectra evaluation. It is capable of analysing the gamma-ray spectrum in the range of 0-3 MeV by semiconductor detector, i.e. Ge(Li) or HPGe, peak searching, net area determining, plotting and spectrum displaying. There are two methods for calculating the net area under peaks; the Covell method and non-linear fitting by the method of Levenberg and Marquardt which can fit any multiplet peak in the spectrum. The graphic display was rather fast and user friendly

UNISAMPO, comprehensive software for gamma-spectrum processing

International Nuclear Information System (INIS)

Aarnio, P.A.; Routti, J.T.; Nikkinen, M.T.

2001-01-01

UNISAMPO is a new member of the SAMPO family of gamma-spectrum analysis programs running on Linux. Its portable graphical user interface relies on Tcl/Tk running an X-client, which obtains services from a X Window System server, allowing natural access to UNISAMPO over the Internet. UNISAMPO features a scripting ability for analyses of thousands of spectra. Peak search is based on stringent statistical criteria and peak fitting has optional step function under each peak of a multiplet. UNISAMPO will analyze 32K spectra with up to 2500 peaks, and 32 peaks in a single multiplet extending over a fitting interval of 1024 channels. It has an interface to the expert system SHAMAN for extensive peak interpretation and radionuclide identification. (author)

Development of Educational Simulation on Spectrum of HPGe Detector and Implementation of Education Program

International Nuclear Information System (INIS)

Seo, K. W.; Joo, Y. C.; Ji, Y. J.; Lee, M. O.; Lee, S. Y.; Jun, Y. K.

2005-12-01

In this development, characteristics of Aptec, Genie2000(Canberra Co, USA), GammaVision(Ortec Co, USA) which are usually used in Korea radioactive measure laboratory, such as peak search, peak fitting, central area position and area calculation, spectrum correction and method for radioactive calculation are included. And radioactive source geometry, absorption of sample itself, methods for correcting coincidence summing effect is developed and the result effected on spectrum analysis teaching material. Developed simulation HPGe detector spectrum are spectrum for correction, spectrum for correcting radio source-detection duration geometry, sample spectrum which need self absorption correction of radio source, peak search spectrum for optimizing peak search offset setting and background spectrum. These spectrum are made similar to real spectrum by processing peak and background which were measured from mix standard volume radio source. Spectrum analysis teaching material is developed more focus on practical thing than theoretical thing, simulation spectrum must be used in spectrum analysis practise. Optimal method for spectrum analysis condition, spectrum correction, Geometry correction and background spectrum analysis are included in teaching material and also ANSI N42 recommended 'Spectrum analysis program test' procedure is included too. Aptec, Genie2000, Gamma Vision software manuals are included in appendix. In order to check the text of developed simulation on spectrum of HPGe detector, in 2004 and 2005, these was implemented in the other regular course as a course for superviser of the handling with RI. And the text and practical procedure were reviewed through the course and were revised

Web accessibility of public universities in Andalusia

Directory of Open Access Journals (Sweden)

Luis Alejandro Casasola Balsells

2017-06-01

Full Text Available This paper describes an analysis conducted in 2015 to evaluate the accessibility of content on Andalusian public university websites. In order to determinate whether these websites are accessible, an assessment has been carried out to check conformance with the latest Web Content Accessibility Guidelines (WCAG 2.0 established by the World Wide Web Consortium (W3C. For this purpose, we have designed a methodology for analysis that combines the use of three automatic tools (eXaminator, MINHAP web accessibility tool, and TAW with a manual analysis to provide a greater reliability and validity of the results. Although the results are acceptable overall, a detailed analysis shows that more is still needed for achieving full accessibility for the entire university community. In this respect, we suggest several corrections to common accessibility errors for facilitating the design of university web portals.

A Novel Dynamic Spectrum Access Framework Based on Reinforcement Learning for Cognitive Radio Sensor Networks

Directory of Open Access Journals (Sweden)

Yun Lin

2016-10-01

Full Text Available Cognitive radio sensor networks are one of the kinds of application where cognitive techniques can be adopted and have many potential applications, challenges and future research trends. According to the research surveys, dynamic spectrum access is an important and necessary technology for future cognitive sensor networks. Traditional methods of dynamic spectrum access are based on spectrum holes and they have some drawbacks, such as low accessibility and high interruptibility, which negatively affect the transmission performance of the sensor networks. To address this problem, in this paper a new initialization mechanism is proposed to establish a communication link and set up a sensor network without adopting spectrum holes to convey control information. Specifically, firstly a transmission channel model for analyzing the maximum accessible capacity for three different polices in a fading environment is discussed. Secondly, a hybrid spectrum access algorithm based on a reinforcement learning model is proposed for the power allocation problem of both the transmission channel and the control channel. Finally, extensive simulations have been conducted and simulation results show that this new algorithm provides a significant improvement in terms of the tradeoff between the control channel reliability and the efficiency of the transmission channel.

A Technique to Speedup Access to Web Contents

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 7. Web Caching - A Technique to Speedup Access to Web Contents. Harsha Srinath Shiva Shankar Ramanna. General Article Volume 7 Issue 7 July 2002 pp 54-62 ... Keywords. World wide web; data caching; internet traffic; web page access.

Technology for computer-stabilized peak of NaI(Tl) gamma spectrum

International Nuclear Information System (INIS)

Chen Jianzhen; Guo Lanying; Ling Qiu; Qu Guopu; Zhao Lihong; Hu Chuangye

2005-01-01

An improved technology for spectrum stabilization of NaI(Tl) gamma spectrum was introduced. This technology is based on the system using a reference peak, which is equivalent gamma peak of 241 Am source. The computer seeks peak's position deviation and computes adjust value of programmable amplifier and controls programmable amplifier to stabilize spectrum by digital PID. This is a technology of spectrum stabilizing with 'hardware + reference-peak + software' and has high stability and fast speed of spectrum stabilizing. (author)

AN AUTOMATIC AND METHODOLOGICAL APPROACH FOR ACCESSIBLE WEB APPLICATIONS

Directory of Open Access Journals (Sweden)

Lourdes Moreno

2007-06-01

Full Text Available Semantic Web approaches try to get the interoperability and communication among technologies and organizations. Nevertheless, sometimes it is forgotten that the Web must be useful for every user, consequently it is necessary to include tools and techniques doing Semantic Web be accessible. Accessibility and usability are two usually joined concepts widely used in web application development, however their meaning are different. Usability means the way to make easy the use but accessibility is referred to the access possibility. For the first one, there are many well proved approaches in real cases. However, accessibility field requires a deeper research that will make feasible the access to disable people and also the access to novel non-disable people due to the cost to automate and maintain accessible applications. In this paper, we propose one architecture to achieve the accessibility in web-environments dealing with the WAI accessibility standard and the Universal Design paradigm. This architecture tries to control the accessibility in web applications development life-cycle following a methodology starting from a semantic conceptual model and leans on description languages and controlled vocabularies.

SBMLmod: a Python-based web application and web service for efficient data integration and model simulation.

Science.gov (United States)

Schäuble, Sascha; Stavrum, Anne-Kristin; Bockwoldt, Mathias; Puntervoll, Pål; Heiland, Ines

2017-06-24

Systems Biology Markup Language (SBML) is the standard model representation and description language in systems biology. Enriching and analysing systems biology models by integrating the multitude of available data, increases the predictive power of these models. This may be a daunting task, which commonly requires bioinformatic competence and scripting. We present SBMLmod, a Python-based web application and service, that automates integration of high throughput data into SBML models. Subsequent steady state analysis is readily accessible via the web service COPASIWS. We illustrate the utility of SBMLmod by integrating gene expression data from different healthy tissues as well as from a cancer dataset into a previously published model of mammalian tryptophan metabolism. SBMLmod is a user-friendly platform for model modification and simulation. The web application is available at http://sbmlmod.uit.no , whereas the WSDL definition file for the web service is accessible via http://sbmlmod.uit.no/SBMLmod.wsdl . Furthermore, the entire package can be downloaded from https://github.com/MolecularBioinformatics/sbml-mod-ws . We envision that SBMLmod will make automated model modification and simulation available to a broader research community.

Application of simulated standard spectra in natural radioactivity measurements using gamma spectrometry

International Nuclear Information System (INIS)

Narayani, K.; Pant, A.D.; Bhosle, Nitin; Anilkumar, S.; Singh, Rajvir; Pradeepkumar, K.S.

2014-01-01

Gamma ray spectrometry is one of the well known analytical techniques for environmental radioactivity measurements. Gamma spectrometer based on NaI(Tl) scintillation detectors is very popular since it offers high efficiency, low cost and case in handling. The poor energy resolution of the NaI(TI) detector is the major disadvantage making tile analysis of complex gamma ray spectra difficult. Least square method or the full spectrum analysis method is widely used for the analysis of complex spectra from scintillation detectors. The main requirement of this method is that the individual standard spectra of all nuclides expected in the complex spectrum in the same measurement geometry must be available. It is not always possible and feasible to have all the standards of nuclides in the desired geometry. A methodology based on the use of simulated standard spectra generated by Monte Carlo technique was proposed for analysis of complex spectra of nuclides. In the present work, for the analysis of 238 U, 233 Th and 40 K in soil samples, the same methodology was applied by using the simulated standard spectra in soil matrix. The details of the simulation method and results analysis of 238 U, 232 Th and 40 K in environmental samples are discussed in this paper

MDWeb and MDMoby: an integrated web-based platform for molecular dynamics simulations.

Science.gov (United States)

Hospital, Adam; Andrio, Pau; Fenollosa, Carles; Cicin-Sain, Damjan; Orozco, Modesto; Gelpí, Josep Lluís

2012-05-01

MDWeb and MDMoby constitute a web-based platform to help access to molecular dynamics (MD) in the standard and high-throughput regime. The platform provides tools to prepare systems from PDB structures mimicking the procedures followed by human experts. It provides inputs and can send simulations for three of the most popular MD packages (Amber, NAMD and Gromacs). Tools for analysis of trajectories, either provided by the user or retrieved from our MoDEL database (http://mmb.pcb.ub.es/MoDEL) are also incorporated. The platform has two ways of access, a set of web-services based on the BioMoby framework (MDMoby), programmatically accessible and a web portal (MDWeb). http://mmb.irbbarcelona.org/MDWeb; additional information and methodology details can be found at the web site ( http://mmb.irbbarcelona.org/MDWeb/help.php)

Working with WebQuests: Making the Web Accessible to Students with Disabilities.

Science.gov (United States)

Kelly, Rebecca

2000-01-01

This article describes how students with disabilities in regular classes are using the WebQuest lesson format to access the Internet. It explains essential WebQuest principles, creating a draft Web page, and WebQuest components. It offers an example of a WebQuest about salvaging the sunken ships, Titanic and Lusitania. A WebQuest planning form is…

Gamma ray energy spectrum of a buried radioactive source

Energy Technology Data Exchange (ETDEWEB)

Massey, N B

1957-07-01

Because of current attempts to utilize airborne gamma-ray scintillation spectrometers as a means of detecting and identifying buried radioactive mineral deposits, it has become important to study the effects of multiple scattering on the gamma-ray energy spectrum of a source buried in a semi-infinite medium. A series of ten experiments was made. First a scintillation detector was located in air at a fixed distance above a 250 microcurie cobalt-60 source suspended in a large tank. The level of water was raised from 25 cm below the source to 50 cm above, and the gamma-ray energy spectrum was observed. It was found that the high energy portion of the cobalt-60 spectrum remained identifiable even when the source was submerged more than five half-lengths. Further, the ratio of the counting rate of the total incident gamma radiation to the counting rate of the primary 1.33 MeV radiation was found to be very nearly linearly proportional to the depth of water cover. This leads to an empirical method for determining the depth of burial of a cobalt-60 point source. (author)

Web-based, GPU-accelerated, Monte Carlo simulation and visualization of indirect radiation imaging detector performance

Energy Technology Data Exchange (ETDEWEB)

Dong, Han; Sharma, Diksha; Badano, Aldo, E-mail: aldo.badano@fda.hhs.gov [Division of Imaging, Diagnostics, and Software Reliability, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 20993 (United States)

2014-12-15

Purpose: Monte Carlo simulations play a vital role in the understanding of the fundamental limitations, design, and optimization of existing and emerging medical imaging systems. Efforts in this area have resulted in the development of a wide variety of open-source software packages. One such package, hybridMANTIS, uses a novel hybrid concept to model indirect scintillator detectors by balancing the computational load using dual CPU and graphics processing unit (GPU) processors, obtaining computational efficiency with reasonable accuracy. In this work, the authors describe two open-source visualization interfaces, webMANTIS and visualMANTIS to facilitate the setup of computational experiments via hybridMANTIS. Methods: The visualization tools visualMANTIS and webMANTIS enable the user to control simulation properties through a user interface. In the case of webMANTIS, control via a web browser allows access through mobile devices such as smartphones or tablets. webMANTIS acts as a server back-end and communicates with an NVIDIA GPU computing cluster that can support multiuser environments where users can execute different experiments in parallel. Results: The output consists of point response and pulse-height spectrum, and optical transport statistics generated by hybridMANTIS. The users can download the output images and statistics through a zip file for future reference. In addition, webMANTIS provides a visualization window that displays a few selected optical photon path as they get transported through the detector columns and allows the user to trace the history of the optical photons. Conclusions: The visualization tools visualMANTIS and webMANTIS provide features such as on the fly generation of pulse-height spectra and response functions for microcolumnar x-ray imagers while allowing users to save simulation parameters and results from prior experiments. The graphical interfaces simplify the simulation setup and allow the user to go directly from specifying

Web-based, GPU-accelerated, Monte Carlo simulation and visualization of indirect radiation imaging detector performance

International Nuclear Information System (INIS)

Dong, Han; Sharma, Diksha; Badano, Aldo

2014-01-01

Purpose: Monte Carlo simulations play a vital role in the understanding of the fundamental limitations, design, and optimization of existing and emerging medical imaging systems. Efforts in this area have resulted in the development of a wide variety of open-source software packages. One such package, hybridMANTIS, uses a novel hybrid concept to model indirect scintillator detectors by balancing the computational load using dual CPU and graphics processing unit (GPU) processors, obtaining computational efficiency with reasonable accuracy. In this work, the authors describe two open-source visualization interfaces, webMANTIS and visualMANTIS to facilitate the setup of computational experiments via hybridMANTIS. Methods: The visualization tools visualMANTIS and webMANTIS enable the user to control simulation properties through a user interface. In the case of webMANTIS, control via a web browser allows access through mobile devices such as smartphones or tablets. webMANTIS acts as a server back-end and communicates with an NVIDIA GPU computing cluster that can support multiuser environments where users can execute different experiments in parallel. Results: The output consists of point response and pulse-height spectrum, and optical transport statistics generated by hybridMANTIS. The users can download the output images and statistics through a zip file for future reference. In addition, webMANTIS provides a visualization window that displays a few selected optical photon path as they get transported through the detector columns and allows the user to trace the history of the optical photons. Conclusions: The visualization tools visualMANTIS and webMANTIS provide features such as on the fly generation of pulse-height spectra and response functions for microcolumnar x-ray imagers while allowing users to save simulation parameters and results from prior experiments. The graphical interfaces simplify the simulation setup and allow the user to go directly from specifying

ESIM_DSN Web-Enabled Distributed Simulation Network

Science.gov (United States)

Bedrossian, Nazareth; Novotny, John

2002-01-01

In this paper, the eSim(sup DSN) approach to achieve distributed simulation capability using the Internet is presented. With this approach a complete simulation can be assembled from component subsystems that run on different computers. The subsystems interact with each other via the Internet The distributed simulation uses a hub-and-spoke type network topology. It provides the ability to dynamically link simulation subsystem models to different computers as well as the ability to assign a particular model to each computer. A proof-of-concept demonstrator is also presented. The eSim(sup DSN) demonstrator can be accessed at http://www.jsc.draper.com/esim which hosts various examples of Web enabled simulations.

Adaptive spectrum decision framework for heterogeneous dynamic spectrum access networks

CSIR Research Space (South Africa)

Masonta, M

2015-09-01

Full Text Available Spectrum decision is the ability of a cognitive radio (CR) system to select the best available spectrum band to satisfy dynamic spectrum access network (DSAN) users¿ quality of service (QoS) requirements without causing harmful interference...

Enabling web users and developers to script accessibility with Accessmonkey.

Science.gov (United States)

Bigham, Jeffrey P; Brudvik, Jeremy T; Leung, Jessica O; Ladner, Richard E

2009-07-01

Efficient web access remains elusive for blind computer users. Previous efforts to improve web accessibility have focused on developer awareness, automated improvement, and legislation, but these approaches have left remaining concerns. First, while many tools can help produce accessible content, most are difficult to integrate into existing developer workflows and rarely offer specific suggestions that developers can implement. Second, tools that automatically improve web content for users generally solve specific problems and are difficult to combine and use on a diversity of existing assistive technology. Finally, although blind web users have proven adept at overcoming the shortcomings of the web and existing tools, they have been only marginally involved in improving the accessibility of their own web experience. In a step toward addressing these concerns, we have developed Accessmonkey, a common scripting framework that web users, web developers and web researchers can use to collaboratively improve accessibility. This framework advances the idea that Javascript and dynamic web content can be used to improve inaccessible content instead of being a cause of it. Using Accessmonkey, web users and developers on different platforms and with potentially different goals can collaboratively make the web more accessible. In this article, we first present the design of the Accessmonkey framework and offer several example scripts that demonstrate the utility of our approach. We conclude by discussing possible future extensions that will provide easy access to scripts as users browse the web and enable non-technical blind users to independently create and share improvements.

EPR structure of the gamma irradiated alanine spectrum

Energy Technology Data Exchange (ETDEWEB)

Cabral P, A; Jimenez D, H; Urena N, F; Galindo, S; Bosch, P

1992-03-15

In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of {gamma}-irradiated powder DL- and L-alanine. (Author)

Multiagent Reinforcement Learning Dynamic Spectrum Access in Cognitive Radios

Directory of Open Access Journals (Sweden)

Wu Chun

2014-02-01

Full Text Available A multiuser independent Q-learning method which does not need information interaction is proposed for multiuser dynamic spectrum accessing in cognitive radios. The method adopts self-learning paradigm, in which each CR user performs reinforcement learning only through observing individual performance reward without spending communication resource on information interaction with others. The reward is defined suitably to present channel quality and channel conflict status. The learning strategy of sufficient exploration, preference for good channel, and punishment for channel conflict is designed to implement multiuser dynamic spectrum accessing. In two users two channels scenario, a fast learning algorithm is proposed and the convergence to maximal whole reward is proved. The simulation results show that, with the proposed method, the CR system can obtain convergence of Nash equilibrium with large probability and achieve great performance of whole reward.

Effect of intermediate zone during gamma-gamma and X-ray spectrum logging of quarry wells with inversive probes

International Nuclear Information System (INIS)

Artsybashev, V.A.; Volkov, A.A.

1981-01-01

Experimental and calculated data on the effect of intermediate zone on results of gamma-gamma and X-ray spectrum logging of quarry wells at chalcopyrite deposits are presented. The measurements have been carried out using 57 Co and 109 Cd sources for intermediate zone represented by water, air and mud. Requirements for technical conditions of wells have been formulated. According to the requirements the application of gamma- gamma method is possible when the thickness of the intermediate zone does not exceed several millimetres and that of X-ray spectrum method - when the thickness does not exceed several hundredths of a millimetre [ru

Atypical Laterality of Resting Gamma Oscillations in Autism Spectrum Disorders

Science.gov (United States)

Maxwell, Christina R.; Villalobos, Michele E.; Schultz, Robert T.; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Kohls, Gregor

2015-01-01

Abnormal brain oscillatory activity has been found in autism spectrum disorders (ASD) and proposed as a potential biomarker. While several studies have investigated gamma oscillations in ASD, none have examined resting gamma power across multiple brain regions. This study investigated resting gamma power using EEG in 15 boys with ASD and 18 age…

Apollo: giving application developers a single point of access to public health models using structured vocabularies and Web services.

Science.gov (United States)

Wagner, Michael M; Levander, John D; Brown, Shawn; Hogan, William R; Millett, Nicholas; Hanna, Josh

2013-01-01

This paper describes the Apollo Web Services and Apollo-SV, its related ontology. The Apollo Web Services give an end-user application a single point of access to multiple epidemic simulators. An end user can specify an analytic problem-which we define as a configuration and a query of results-exactly once and submit it to multiple epidemic simulators. The end user represents the analytic problem using a standard syntax and vocabulary, not the native languages of the simulators. We have demonstrated the feasibility of this design by implementing a set of Apollo services that provide access to two epidemic simulators and two visualizer services.

Ocean Drilling Program: Web Site Access Statistics

Science.gov (United States)

web site ODP/TAMU Science Operator Home Ocean Drilling Program Web Site Access Statistics* Overview See statistics for JOIDES members. See statistics for Janus database. 1997 October November December

SWS: accessing SRS sites contents through Web Services.

Science.gov (United States)

Romano, Paolo; Marra, Domenico

2008-03-26

Web Services and Workflow Management Systems can support creation and deployment of network systems, able to automate data analysis and retrieval processes in biomedical research. Web Services have been implemented at bioinformatics centres and workflow systems have been proposed for biological data analysis. New databanks are often developed by taking into account these technologies, but many existing databases do not allow a programmatic access. Only a fraction of available databanks can thus be queried through programmatic interfaces. SRS is a well know indexing and search engine for biomedical databanks offering public access to many databanks and analysis tools. Unfortunately, these data are not easily and efficiently accessible through Web Services. We have developed 'SRS by WS' (SWS), a tool that makes information available in SRS sites accessible through Web Services. Information on known sites is maintained in a database, srsdb. SWS consists in a suite of WS that can query both srsdb, for information on sites and databases, and SRS sites. SWS returns results in a text-only format and can be accessed through a WSDL compliant client. SWS enables interoperability between workflow systems and SRS implementations, by also managing access to alternative sites, in order to cope with network and maintenance problems, and selecting the most up-to-date among available systems. Development and implementation of Web Services, allowing to make a programmatic access to an exhaustive set of biomedical databases can significantly improve automation of in-silico analysis. SWS supports this activity by making biological databanks that are managed in public SRS sites available through a programmatic interface.

Decision Analysis of Dynamic Spectrum Access Rules

Energy Technology Data Exchange (ETDEWEB)

Juan D. Deaton; Luiz A. DaSilva; Christian Wernz

2011-12-01

A current trend in spectrum regulation is to incorporate spectrum sharing through the design of spectrum access rules that support Dynamic Spectrum Access (DSA). This paper develops a decision-theoretic framework for regulators to assess the impacts of different decision rules on both primary and secondary operators. We analyze access rules based on sensing and exclusion areas, which in practice can be enforced through geolocation databases. Our results show that receiver-only sensing provides insufficient protection for primary and co-existing secondary users and overall low social welfare. On the other hand, using sensing information between the transmitter and receiver of a communication link, provides dramatic increases in system performance. The performance of using these link end points is relatively close to that of using many cooperative sensing nodes associated to the same access point and large link exclusion areas. These results are useful to regulators and network developers in understanding in developing rules for future DSA regulation.

The application of full spectrum gamma-gamma techniques to density/photoelectric cross section logging

International Nuclear Information System (INIS)

Minette, D.C.; Hubner, B.G.; Koudelka, J.C.; Schmidt, M.

1986-01-01

The Compensated Z-Densilog instrument is a new full spectrum gamma-gamma logging instrument, measuring the density and photoelectric cross section (Pe) of the formation. This instrument represents an advancement over present instruments in that the observed gamma spectrum is sent to the surface as a full 256-channel spectrum instead of count rates in a few energy gates. This advancement is made possible by the use of high speed digital electronics which are protected from the high temperatures observed downhole by custom-built flasks. In this paper, the new advanced electronics are considered in some detail. This consideration includes a comparison of full spectrum data acquisition with the multiple discriminator window technique, which is the foundation of the ''few gate'' method. Both of these methods are critiqued based upon electronic stability and the information obtained. The full spectrum provided by high speed electronics facilitates a much more sophisticated data analysis. This data analysis, based on phenomenological model of the instrument (Minette, 1984), includes real time compensation for changes in detector gain and crystal resolution. It also includes a ''four-dimensional'' rib-spine plot, which separates the compensation for mudcake density from the compensation for the Pe of the formation and the mudcake. Also included in the software are real time error minimization and real time decision-making techniques. These techniques maximize the sensitivity of the instrument to the density and Pe of the formation and minimize error due to statistical fluctuations. Gain and resolution compensation completes the data analysis. This compensation virtually eliminates density and Pe errors caused by changing gain and resolution

Simulation study on unfolding methods for diagnostic X-rays and mixed gamma rays

International Nuclear Information System (INIS)

Hashimoto, Makoto; Ohtaka, Masahiko; Ara, Kuniaki; Kanno, Ikuo; Imamura, Ryo; Mikami, Kenta; Nomiya, Seiichiro; Onabe, Hideaki

2009-01-01

A photon detector operating in current mode that can sense X-ray energy distribution has been reported. This detector consists of a row of several segment detectors. The energy distribution is derived using an unfolding technique. In this paper, comparisons of the unfolding techniques among error reduction, spectrum surveillance, and neural network methods are discussed through simulation studies on the detection of diagnostic X-rays and gamma rays emitted by a mixture of 137 Cs and 60 Co. For diagnostic X-ray measurement, the spectrum surveillance and neural network methods appeared promising, while the error reduction method yielded poor results. However, in the case of measuring mixtures of gamma rays, the error reduction method was both sufficient and effective. (author)

A new type gamma-ray spectrum monitoring system

CERN Document Server

Cheng Bo; Zhou Jian Bin; Zhang Zhi Ming; Tong Yun Fu

2002-01-01

This new radiation monitoring system can be used to monitor the radiation of building materials and the radiation of atmosphere, to explore and evaluate rock for building in the field, and this system can be used to monitor the gamma irradiation near the nuclear establishments in the average situation and in the serious situation of the radiation incident have happened. The control core of this monitoring system is SCM-AT89C52, and gamma-ray sensing head consists of scintillator phi 50 mm x 50 mm NaI(Tl) and PMT GDB44. This system can be used to measure the whole gamma-ray spectrum of 256 channels

Spectrum analysis with indoor multi-channels gamma-rays spectrometer (NaI(Tl))

International Nuclear Information System (INIS)

Hou Shengli; Fan Weihua

2005-01-01

Two calculational methods for analyzing the spectrum which measured by indoor low background multi-channels gamma-rays spectrometer (Na(Tl)) to get the specific activity of 226 Ra, 232 Th and 40 K of the sample are discussed, they are the spectrum analysis method and the characteristic energy peak method (inverse matrix method) respectively. The sample spectrum are analyzed with the program designed according to the two methods, and compared with the results by HPGe gamma-rays spectrometer, showing that the relative deviation is ≤10% with the two methods. (authors)

Learning Task Knowledge from Dialog and Web Access

Directory of Open Access Journals (Sweden)

Vittorio Perera

2015-06-01

Full Text Available We present KnoWDiaL, an approach for Learning and using task-relevant Knowledge from human-robot Dialog and access to the Web. KnoWDiaL assumes that there is an autonomous agent that performs tasks, as requested by humans through speech. The agent needs to “understand” the request, (i.e., to fully ground the task until it can proceed to plan for and execute it. KnoWDiaL contributes such understanding by using and updating a Knowledge Base, by dialoguing with the user, and by accessing the web. We believe that KnoWDiaL, as we present it, can be applied to general autonomous agents. However, we focus on our work with our autonomous collaborative robot, CoBot, which executes service tasks in a building, moving around and transporting objects between locations. Hence, the knowledge acquired and accessed consists of groundings of language to robot actions, and building locations, persons, and objects. KnoWDiaL handles the interpretation of voice commands, is robust regarding speech recognition errors, and is able to learn commands involving referring expressions in an open domain, (i.e., without requiring a lexicon. We present in detail the multiple components of KnoWDiaL, namely a frame-semantic parser, a probabilistic grounding model, a web-based predicate evaluator, a dialog manager, and the weighted predicate-based Knowledge Base. We illustrate the knowledge access and updates from the dialog and Web access, through detailed and complete examples. We further evaluate the correctness of the predicate instances learned into the Knowledge Base, and show the increase in dialog efficiency as a function of the number of interactions. We have extensively and successfully used KnoWDiaL in CoBot dialoguing and accessing the Web, and extract a few corresponding example sequences from captured videos.

TPASS: a gamma-ray spectrum analysis and isotope identification computer code

International Nuclear Information System (INIS)

Dickens, J.K.

1981-03-01

The gamma-ray spectral data-reduction and analysis computer code TPASS is described. This computer code is used to analyze complex Ge(Li) gamma-ray spectra to obtain peak areas corrected for detector efficiencies, from which are determined gamma-ray yields. These yields are compared with an isotope gamma-ray data file to determine the contributions to the observed spectrum from decay of specific radionuclides. A complete FORTRAN listing of the code and a complex test case are given

GSAP: FORTRAN code for gamma-spectrum analysis

International Nuclear Information System (INIS)

Hnatowicz, V.; Kozma, P.; Ilyushchenko, V.I.

1989-01-01

The GSAP program performs fully automatic evaluation of gamma-ray energy spectra measured with semiconductor detectors. After the input data comprising experimental spectrum, energy and FWHM calibrations and parameters controlling the peak search are supplied, the program starts peak searching from the spectrum beginning. The detected peaks are arranged into multiplets which are unfolded by standard non-linear least-squares-fit assuming Gaussian peak and linear background. The program proceeds until all multiplets are processed. The determined peak parameters are printed and the result of each particular fit is shown in the graphical form. 6 refs

EPR structure of the gamma irradiated alanine spectrum

International Nuclear Information System (INIS)

Cabral P, A.; Jimenez D, H.; Urena N, F.; Galindo, S.; Bosch, P.

1992-03-01

In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of γ-irradiated powder DL- and L-alanine. (Author)

Optimal Pricing of Spectrum Resources in Wireless Opportunistic Access

Directory of Open Access Journals (Sweden)

Hanna Bogucka

2012-01-01

Full Text Available We consider opportunistic access to spectrum resources in cognitive wireless networks. The users equipment, or the network nodes in general are able to sense the spectrum and adopt a subset of available resources (the spectrum and the power individually and independently in a distributed manner, that is, based on their local channel quality information and not knowing the Channel State Information (CSI of the other nodes' links in the considered network area. In such a network scenery, the competition of nodes for available resources is observed, which can be modeled as a game. To obtain spectrally efficient and fair spectrum allocation in this competitive environment with the nodes having no information on the other players, taxation of resources is applied to coerce desired behavior of the competitors. In the paper, we present mathematical formulation of the problem of finding the optimal taxation rate (common for all nodes and propose a reduced-complexity algorithm for this optimization. Simulation results for these derived optimal values in various scenarios are also provided.

Accessible Web Design - The Power of the Personal Message.

Science.gov (United States)

Whitney, Gill

2015-01-01

The aim of this paper is to describe ongoing research being carried out to enable people with visual impairments to communicate directly with designers and specifiers of hobby and community web sites to maximise the accessibility of their sites. The research started with an investigation of the accessibility of community and hobby web sites as perceived by a group of visually impaired end users. It is continuing with an investigation into how to best to communicate with web designers who are not experts in web accessibility. The research is making use of communication theory to investigate how terminology describing personal experience can be used in the most effective and powerful way. By working with the users using a Delphi study the research has ensured that the views of the visually impaired end users is successfully transmitted.

Dynamic Spectrum Access for Internet of Things Service in Cognitive Radio-Enabled LPWANs.

Science.gov (United States)

Moon, Bongkyo

2017-12-05

In this paper, we focus on a dynamic spectrum access strategy for Internet of Things (IoT) applications in two types of radio systems: cellular networks and cognitive radio-enabled low power wide area networks (CR-LPWANs). The spectrum channel contention between the licensed cellular networks and the unlicensed CR-LPWANs, which work with them, only takes place within the cellular radio spectrum range. Our aim is to maximize the spectrum capacity for the unlicensed users while ensuring that it never interferes with the licensed network. Therefore, in this paper we propose a dynamic spectrum access strategy for CR-LPWANs operating in both licensed and unlicensed bands. The simulation and the numerical analysis by using a matrix geometric approach for the strategy are presented. Finally, we obtain the blocking probability of the licensed users, the mean dwell time of the unlicensed user, and the total carried traffic and combined service quality for the licensed and unlicensed users. The results show that the proposed strategy can maximize the spectrum capacity for the unlicensed users using IoT applications as well as keep the service quality of the licensed users independent of them.

H1DS: A new web-based data access system

Energy Technology Data Exchange (ETDEWEB)

Pretty, D.G., E-mail: david.pretty@anu.edu.au; Blackwell, B.D.

2014-05-15

Highlights: • We present H1DS, a new RESTful web service for accessing fusion data. • We examine the scalability and extensibility of H1DS. • We present a fast and user friendly web browser client for the H1DS web service. • A summary relational database is presented as an application of the H1DS API. - Abstract: A new data access system, H1DS, has been developed and deployed for the H-1 Heliac at the Australian Plasma Fusion Research Facility. The data system provides access to fusion data via a RESTful web service. With the URL acting as the API to the data system, H1DS provides a scalable and extensible framework which is intuitive to new users, and allows access from any internet connected device. The H1DS framework, originally designed to work with MDSplus, has a modular design which can be extended to provide access to alternative data storage systems.

H1DS: A new web-based data access system

International Nuclear Information System (INIS)

Pretty, D.G.; Blackwell, B.D.

2014-01-01

Highlights: • We present H1DS, a new RESTful web service for accessing fusion data. • We examine the scalability and extensibility of H1DS. • We present a fast and user friendly web browser client for the H1DS web service. • A summary relational database is presented as an application of the H1DS API. - Abstract: A new data access system, H1DS, has been developed and deployed for the H-1 Heliac at the Australian Plasma Fusion Research Facility. The data system provides access to fusion data via a RESTful web service. With the URL acting as the API to the data system, H1DS provides a scalable and extensible framework which is intuitive to new users, and allows access from any internet connected device. The H1DS framework, originally designed to work with MDSplus, has a modular design which can be extended to provide access to alternative data storage systems

Interactive Learning Environment: Web-based Virtual Hydrological Simulation System using Augmented and Immersive Reality

Science.gov (United States)

Demir, I.

2014-12-01

Recent developments in internet technologies make it possible to manage and visualize large data on the web. Novel visualization techniques and interactive user interfaces allow users to create realistic environments, and interact with data to gain insight from simulations and environmental observations. The hydrological simulation system is a web-based 3D interactive learning environment for teaching hydrological processes and concepts. The simulation systems provides a visually striking platform with realistic terrain information, and water simulation. Students can create or load predefined scenarios, control environmental parameters, and evaluate environmental mitigation alternatives. The web-based simulation system provides an environment for students to learn about the hydrological processes (e.g. flooding and flood damage), and effects of development and human activity in the floodplain. The system utilizes latest web technologies and graphics processing unit (GPU) for water simulation and object collisions on the terrain. Users can access the system in three visualization modes including virtual reality, augmented reality, and immersive reality using heads-up display. The system provides various scenarios customized to fit the age and education level of various users. This presentation provides an overview of the web-based flood simulation system, and demonstrates the capabilities of the system for various visualization and interaction modes.

BC404 scintillators as gamma locators studied via Geant4 simulations

Science.gov (United States)

Cortés, M. L.; Hoischen, R.; Eisenhauer, K.; Gerl, J.; Pietralla, N.

2014-05-01

In many applications in industry and academia, an accurate determination of the direction from where gamma rays are emitted is either needed or desirable. Ion-beam therapy treatments, the search for orphan sources, and homeland security applications are examples of fields that can benefit from directional sensitivity to gamma-radiation. Scintillation detectors are a good option for these types of applications as they have relatively low cost, are easy to handle and can be produced in a large range of different sizes. In this work a Geant4 simulation was developed to study the directional sensitivity of different BC404 scintillator geometries and arrangements. The simulation includes all the physical processes relevant for gamma detection in a scintillator. In particular, the creation and propagation of optical photons inside the scintillator was included. A simplified photomultiplier tube model was also simulated. The physical principle exploited is the angular dependence of the shape of the energy spectrum obtained from thin scintillator layers when irradiated from different angles. After an experimental confirmation of the working principle of the device and a check of the simulation, the possibilities and limitations of directional sensitivity to gamma radiation using scintillator layers was tested. For this purpose, point-like sources of typical energies expected in ion-beam therapy were used. Optimal scintillator thicknesses for different energies were determined and the setup efficiencies calculated. The use of arrays of scintillators to reconstruct the direction of incoming gamma rays was also studied. For this case, a spherical source emitting Bremsstrahlung radiation was used together with a setup consisting of scintillator layers. The capability of this setup to identify the center of the extended source was studied together with its angular resolution.

Access Control of Web- and Java-Based Applications

Science.gov (United States)

Tso, Kam S.; Pajevski, Michael J.

2013-01-01

Cybersecurity has become a great concern as threats of service interruption, unauthorized access, stealing and altering of information, and spreading of viruses have become more prevalent and serious. Application layer access control of applications is a critical component in the overall security solution that also includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. An access control solution, based on an open-source access manager augmented with custom software components, was developed to provide protection to both Web-based and Javabased client and server applications. The DISA Security Service (DISA-SS) provides common access control capabilities for AMMOS software applications through a set of application programming interfaces (APIs) and network- accessible security services for authentication, single sign-on, authorization checking, and authorization policy management. The OpenAM access management technology designed for Web applications can be extended to meet the needs of Java thick clients and stand alone servers that are commonly used in the JPL AMMOS environment. The DISA-SS reusable components have greatly reduced the effort for each AMMOS subsystem to develop its own access control strategy. The novelty of this work is that it leverages an open-source access management product that was designed for Webbased applications to provide access control for Java thick clients and Java standalone servers. Thick clients and standalone servers are still commonly used in businesses and government, especially for applications that require rich graphical user interfaces and high-performance visualization that cannot be met by thin clients running on Web browsers

A web portal for hydrodynamical, cosmological simulations

Science.gov (United States)

Ragagnin, A.; Dolag, K.; Biffi, V.; Cadolle Bel, M.; Hammer, N. J.; Krukau, A.; Petkova, M.; Steinborn, D.

2017-07-01

This article describes a data centre hosting a web portal for accessing and sharing the output of large, cosmological, hydro-dynamical simulations with a broad scientific community. It also allows users to receive related scientific data products by directly processing the raw simulation data on a remote computing cluster. The data centre has a multi-layer structure: a web portal, a job control layer, a computing cluster and a HPC storage system. The outer layer enables users to choose an object from the simulations. Objects can be selected by visually inspecting 2D maps of the simulation data, by performing highly compounded and elaborated queries or graphically by plotting arbitrary combinations of properties. The user can run analysis tools on a chosen object. These services allow users to run analysis tools on the raw simulation data. The job control layer is responsible for handling and performing the analysis jobs, which are executed on a computing cluster. The innermost layer is formed by a HPC storage system which hosts the large, raw simulation data. The following services are available for the users: (I) CLUSTERINSPECT visualizes properties of member galaxies of a selected galaxy cluster; (II) SIMCUT returns the raw data of a sub-volume around a selected object from a simulation, containing all the original, hydro-dynamical quantities; (III) SMAC creates idealized 2D maps of various, physical quantities and observables of a selected object; (IV) PHOX generates virtual X-ray observations with specifications of various current and upcoming instruments.

Web Based Remote Access Microcontroller Laboratory

OpenAIRE

H. Çimen; İ. Yabanova; M. Nartkaya; S. M. Çinar

2008-01-01

This paper presents a web based remote access microcontroller laboratory. Because of accelerated development in electronics and computer technologies, microcontroller-based devices and appliances are found in all aspects of our daily life. Before the implementation of remote access microcontroller laboratory an experiment set is developed by teaching staff for training microcontrollers. Requirement of technical teaching and industrial applications are considered when expe...

BioServices: a common Python package to access biological Web Services programmatically.

Science.gov (United States)

Cokelaer, Thomas; Pultz, Dennis; Harder, Lea M; Serra-Musach, Jordi; Saez-Rodriguez, Julio

2013-12-15

Web interfaces provide access to numerous biological databases. Many can be accessed to in a programmatic way thanks to Web Services. Building applications that combine several of them would benefit from a single framework. BioServices is a comprehensive Python framework that provides programmatic access to major bioinformatics Web Services (e.g. KEGG, UniProt, BioModels, ChEMBLdb). Wrapping additional Web Services based either on Representational State Transfer or Simple Object Access Protocol/Web Services Description Language technologies is eased by the usage of object-oriented programming. BioServices releases and documentation are available at http://pypi.python.org/pypi/bioservices under a GPL-v3 license.

A Framework for Transparently Accessing Deep Web Sources

Science.gov (United States)

Dragut, Eduard Constantin

2010-01-01

An increasing number of Web sites expose their content via query interfaces, many of them offering the same type of products/services (e.g., flight tickets, car rental/purchasing). They constitute the so-called "Deep Web". Accessing the content on the Deep Web has been a long-standing challenge for the database community. For a user interested in…

Content accessibility of Web documents: Overview of concepts and needed standards

DEFF Research Database (Denmark)

Alapetite, A.

2006-01-01

The concept of Web accessibility refers to a combined set of measures, namely, how easily and how efficiently different types of users may make use of a given service. While some recommendations for accessibility are focusing on people with variousspecific disabilities, this document seeks...... to broaden the scope to any type of user and any type of use case. The document provides an introduction to some required concepts and technical standards for designing accessible Web sites. A brief review of thelegal requirements in a few countries for Web accessibility complements the recommendations...

The application of particle swarm optimization to identify gamma spectrum with neural network

International Nuclear Information System (INIS)

Shi Dongsheng; Di Yuming; Zhou Chunlin

2006-01-01

Aiming at the shortcomings that BP algorithm is usually trapped to a local optimum and it has a low speed of convergence in the application of neural network to identify gamma spectrum, according to the advantage of the globe optimal searching of particle swarm optimization, this paper put forward a new algorithm for neural network training by combining BP algorithm and Particle Swarm Optimization-mixed PSO-BP algorithm. In the application to identify gamma spectrum, the new algorithm overcomes the shortcoming that BP algorithm is usually trapped to a local optimum and the neural network trained by it has a high ability of generalization with identification result of one hundred percent correct. Practical example shows that the mixed PSO-BP algorithm can effectively and reliably be used to identify gamma spectrum. (authors)

Analysis of the photon spectrum in inclusive B --> X$_{s}\\gamma$ decays

CERN Document Server

Neubert, M

1994-01-01

Using a combination of the operator product and heavy quark expansions we resum the leading nonperturbative contributions to the inclusive photon spectrum in $B\\to X_s\\,\\gamma$ decays. The shape of the spectrum is determined by a structure function, which describes the distribution of the light-cone momentum fraction of the $b$-quark inside the $B$ meson. The moments of the spectrum are proportional to forward matrix elements of higher-dimension operators. As a byproduct, we obtain the bound $\\lambda_1<0$ for one of the fundamental parameters of the heavy quark effective theory. The integral over the $B\\to X_s\\,\\gamma$ structure function is related to the shape function that governs the fall-off of the lepton spectrum close to the endpoint in $B\\to X_u\\,\\ell\\,\\bar\

X-ray emission from open star clusters with Spectrum-Rontgen-Gamma

DEFF Research Database (Denmark)

Singh, K.P.; Ojha, D.K.; Schnopper, H.W.

1998-01-01

The study of X-ray emission from co-evolving populations of stars in open dusters is extremely important for understanding the dynamo activity among the stars. With this objective, we propose to observe a number of open clusters in the X-ray and UV bands using SPECTRUM-Rontgen-Gamma. The high...... throughput of SPECTRUM-Rontgen-Gamma will help detect main sequence stars like Sun in middle-aged and old clusters. We will study the relationships between various parameters - age, rotation, abundance, UBV colors, X-ray luminosity, coronal temperature etc. X-ray spectra of younger and brighter populations...

Modeling and simulation of gamma camera

International Nuclear Information System (INIS)

Singh, B.; Kataria, S.K.; Samuel, A.M.

2002-08-01

Simulation techniques play a vital role in designing of sophisticated instruments and also for the training of operating and maintenance staff. Gamma camera systems have been used for functional imaging in nuclear medicine. Functional images are derived from the external counting of the gamma emitting radioactive tracer that after introduction in to the body mimics the behavior of native biochemical compound. The position sensitive detector yield the coordinates of the gamma ray interaction with the detector and are used to estimate the point of gamma ray emission within the tracer distribution space. This advanced imaging device is thus dependent on the performance of algorithm for coordinate computing, estimation of point of emission, generation of image and display of the image data. Contemporary systems also have protocols for quality control and clinical evaluation of imaging studies. Simulation of this processing leads to understanding of the basic camera design problems. This report describes a PC based package for design and simulation of gamma camera along with the options of simulating data acquisition and quality control of imaging studies. Image display and data processing the other options implemented in SIMCAM will be described in separate reports (under preparation). Gamma camera modeling and simulation in SIMCAM has preset configuration of the design parameters for various sizes of crystal detector with the option to pack the PMT on hexagon or square lattice. Different algorithm for computation of coordinates and spatial distortion removal are allowed in addition to the simulation of energy correction circuit. The user can simulate different static, dynamic, MUGA and SPECT studies. The acquired/ simulated data is processed for quality control and clinical evaluation of the imaging studies. Results show that the program can be used to assess these performances. Also the variations in performance parameters can be assessed due to the induced

Simulated and measured neutron/gamma light output distribution for poly-energetic neutron/gamma sources

Science.gov (United States)

Hosseini, S. A.; Zangian, M.; Aghabozorgi, S.

2018-03-01

In the present paper, the light output distribution due to poly-energetic neutron/gamma (neutron or gamma) source was calculated using the developed MCNPX-ESUT-PE (MCNPX-Energy engineering of Sharif University of Technology-Poly Energetic version) computational code. The simulation of light output distribution includes the modeling of the particle transport, the calculation of scintillation photons induced by charged particles, simulation of the scintillation photon transport and considering the light resolution obtained from the experiment. The developed computational code is able to simulate the light output distribution due to any neutron/gamma source. In the experimental step of the present study, the neutron-gamma discrimination based on the light output distribution was performed using the zero crossing method. As a case study, 241Am-9Be source was considered and the simulated and measured neutron/gamma light output distributions were compared. There is an acceptable agreement between the discriminated neutron/gamma light output distributions obtained from the simulation and experiment.

Architecture for large-scale automatic web accessibility evaluation based on the UWEM methodology

DEFF Research Database (Denmark)

Ulltveit-Moe, Nils; Olsen, Morten Goodwin; Pillai, Anand B.

2008-01-01

The European Internet Accessibility project (EIAO) has developed an Observatory for performing large scale automatic web accessibility evaluations of public sector web sites in Europe. The architecture includes a distributed web crawler that crawls web sites for links until either a given budget...... of web pages have been identified or the web site has been crawled exhaustively. Subsequently, a uniform random subset of the crawled web pages is sampled and sent for accessibility evaluation and the evaluation results are stored in a Resource Description Format (RDF) database that is later loaded...... challenges that the project faced and the solutions developed towards building a system capable of regular large-scale accessibility evaluations with sufficient capacity and stability. It also outlines some possible future architectural improvements....

JavaScript Access to DICOM Network and Objects in Web Browser.

Science.gov (United States)

Drnasin, Ivan; Grgić, Mislav; Gogić, Goran

2017-10-01

Digital imaging and communications in medicine (DICOM) 3.0 standard provides the baseline for the picture archiving and communication systems (PACS). The development of Internet and various communication media initiated demand for non-DICOM access to PACS systems. Ever-increasing utilization of the web browsers, laptops and handheld devices, as opposed to desktop applications and static organizational computers, lead to development of different web technologies. The DICOM standard officials accepted those subsequently as tools of alternative access. This paper provides an overview of the current state of development of the web access technology to the DICOM repositories. It presents a different approach of using HTML5 features of the web browsers through the JavaScript language and the WebSocket protocol by enabling real-time communication with DICOM repositories. JavaScript DICOM network library, DICOM to WebSocket proxy and a proof-of-concept web application that qualifies as a DICOM 3.0 device were developed.

Optimal Caching in Multicast 5G Networks with Opportunistic Spectrum Access

KAUST Repository

Emara, Mostafa

2018-01-15

Cache-enabled small base station (SBS) densification is foreseen as a key component of 5G cellular networks. This architecture enables storing popular files at the network edge (i.e., SBS caches), which empowers local communication and alleviates traffic congestions at the core/backhaul network. This paper develops a mathematical framework, based on stochastic geometry, to characterize the hit probability of a cache-enabled multicast 5G network with SBS multi-channel capabilities and opportunistic spectrum access. To this end, we first derive the hit probability by characterizing opportunistic spectrum access success probabilities, service distance distributions, and coverage probabilities. The optimal caching distribution to maximize the hit probability is then computed. The performance and trade-offs of the derived optimal caching distributions are then assessed and compared with two widely employed caching distribution schemes, namely uniform and Zipf caching, through numerical results and extensive simulations. It is shown that the Zipf caching almost optimal only in scenarios with large number of available channels and large cache sizes.

A performance study of WebDav access to storages within the Belle II collaboration

Science.gov (United States)

Pardi, S.; Russo, G.

2017-10-01

WebDav and HTTP are becoming popular protocols for data access in the High Energy Physics community. The most used Grid and Cloud storage solutions provide such kind of interfaces, in this scenario tuning and performance evaluation became crucial aspects to promote the adoption of these protocols within the Belle II community. In this work, we present the results of a large-scale test activity, made with the goal to evaluate performances and reliability of the WebDav protocol, and study a possible adoption for the user analysis. More specifically, we considered a pilot infrastructure composed by a set of storage elements configured with the WebDav interface, hosted at the Belle II sites. The performance tests include a comparison with xrootd and gridftp. As reference tests we used a set of analysis jobs running under the Belle II software framework, accessing the input data with the ROOT I/O library, in order to simulate as much as possible a realistic user activity. The final analysis shows the possibility to achieve promising performances with WebDav on different storage systems, and gives an interesting feedback, for Belle II community and for other high energy physics experiments.

Development, implementation and pilot evaluation of a Web-based Virtual Patient Case Simulation environment--Web-SP.

Science.gov (United States)

Zary, Nabil; Johnson, Gunilla; Boberg, Jonas; Fors, Uno G H

2006-02-21

The Web-based Simulation of Patients (Web-SP) project was initiated in order to facilitate the use of realistic and interactive virtual patients (VP) in medicine and healthcare education. Web-SP focuses on moving beyond the technology savvy teachers, when integrating simulation-based education into health sciences curricula, by making the creation and use of virtual patients easier. The project strives to provide a common generic platform for design/creation, management, evaluation and sharing of web-based virtual patients. The aim of this study was to evaluate if it was possible to develop a web-based virtual patient case simulation environment where the entire case authoring process might be handled by teachers and which would be flexible enough to be used in different healthcare disciplines. The Web-SP system was constructed to support easy authoring, management and presentation of virtual patient cases. The case authoring environment was found to facilitate for teachers to create full-fledged patient cases without the assistance of computer specialists. Web-SP was successfully implemented at several universities by taking into account key factors such as cost, access, security, scalability and flexibility. Pilot evaluations in medical, dentistry and pharmacy courses shows that students regarded Web-SP as easy to use, engaging and to be of educational value. Cases adapted for all three disciplines were judged to be of significant educational value by the course leaders. The Web-SP system seems to fulfil the aim of providing a common generic platform for creation, management and evaluation of web-based virtual patient cases. The responses regarding the authoring environment indicated that the system might be user-friendly enough to appeal to a majority of the academic staff. In terms of implementation strengths, Web-SP seems to fulfil most needs from course directors and teachers from various educational institutions and disciplines. The system is currently in

Web services interface to EPICS channel access

Institute of Scientific and Technical Information of China (English)

DUAN Lei; SHEN Liren

2008-01-01

Web services is used in Experimental Physics and Industrial Control System (EPICS). Combined with EPICS Channel Access protocol, Web services' high usability, platform independence and language independence can be used to design a fully transparent and uniform software interface layer, which helps us complete channel data acquisition, modification and monitoring functions. This software interface layer, a cross-platform of cross-language,has good interopcrability and reusability.

Web services interface to EPICS channel access

International Nuclear Information System (INIS)

Duan Lei; Shen Liren

2008-01-01

Web services is used in Experimental Physics and Industrial Control System (EPICS). Combined with EPICS Channel Access protocol, Web services high usability, platform independence and language independence can be used to design a fully transparent and uniform software interface layer, which helps us complete channel data acquisition, modification and monitoring functions. This software interface layer, a cross-platform of cross-language, has good interoperability and reusability. (authors)

On the omnipresent background gamma radiation of the continuous spectrum

Energy Technology Data Exchange (ETDEWEB)

Banjanac, R.; Maletić, D.; Joković, D., E-mail: yokovic@ipb.ac.rs; Veselinović, N.; Dragić, A.; Udovičić, V.; Aničin, I.

2014-05-01

The background spectrum of a germanium detector, shielded from the radiations arriving from the lower and open for the radiations arriving from the upper hemisphere, is studied by means of absorption measurements, both in a ground level and in an underground laboratory. The low-energy continuous portion of this background spectrum that peaks at around 100 keV, which is its most intense component, is found to be of very similar shape at the two locations. It is established that it is mostly due to the radiations of the real continuous spectrum, which is quite similar to the instrumental one. The intensity of this radiation is in our cases estimated to about 8000 photons/(m{sup 2}s·2π·srad) in the ground level laboratory, and to about 5000 photons/(m{sup 2}s·2π·srad) in the underground laboratory, at the depth of 25 m.w.e. Simulations by GEANT4 and CORSIKA demonstrate that this radiation is predominantly of terrestrial origin, due to environmental gamma radiations scattered off the materials that surround the detector (the “skyshine radiation”), and to a far less extent to cosmic rays of degraded energy. - Highlights: • We studied the low-energy part of continuous background spectra of germanium detectors. • The study was performed at the ground level and at the shallow underground sites. • The instrumental spectrum is due to radiations of the similar continuous spectrum. • The low-energy radiation is of both terrestrial and cosmic-ray origin. • In our study, we find that this radiation is of predominantly terrestrial origin.

Hera-FFX: a Firefox add-on for Semi-automatic Web Accessibility Evaluation

OpenAIRE

Fuertes Castro, José Luis; González, Ricardo; Gutiérrez, Emmanuelle; Martínez Normand, Loïc

2009-01-01

Website accessibility evaluation is a complex task requiring a combination of human expertise and software support. There are several online and offline tools to support the manual web accessibility evaluation process. However, they all have some weaknesses because none of them includes all the desired features. In this paper we present Hera-FFX, an add-on for the Firefox web browser that supports semi-automatic web accessibility evaluation.

Simulation in the Internet age: the place of web-based simulation in nursing education. An integrative review.

Science.gov (United States)

Cant, Robyn P; Cooper, Simon J

2014-12-01

The objective of this article was to review the literature on utilisation and place of Web-based simulation within nursing education. Web-based simulation combines electronic multimedia options with a central video or virtual world to produce interactive learning activities mediated by the learner. An integrative review. A search was conducted of healthcare databases between 2000 and 2014 and of Internet sources for hosted simulation programs in nursing. Eighteen primary programs were identified for inclusion. A strategy for integrative review was adopted in which studies were identified, filtered, classified, analysed and compared. Of 18 programs, two game-based programs were identified which represented a 'virtual world' in which students could simultaneously or individually immerse themselves in a character role-play. However, most programs (n=10) taught an aspect of procedural patient care using multimedia (e.g. video, audio, graphics, quiz, text, memo). Time-limited sequences, feedback and reflective activities were often incorporated. Other studies (n=8) taught interpersonal communication skills or technical skills for equipment use. Descriptive study outcomes indicated ease of program use, strong satisfaction with learning and appreciation of program accessibility. Additionally, four studies reported significant improvements in knowledge post-intervention. Web-based simulation is highly acceptable to students and appears to provide learning benefits that align with other simulation approaches and it augments face-to-face teaching. Web-based simulation is likely to have a major place in nursing curricula in the next decade, yet further research is necessary to objectively evaluate learner outcomes and to justify its use. Copyright © 2014 Elsevier Ltd. All rights reserved.

Accessing the SEED genome databases via Web services API: tools for programmers.

Science.gov (United States)

Disz, Terry; Akhter, Sajia; Cuevas, Daniel; Olson, Robert; Overbeek, Ross; Vonstein, Veronika; Stevens, Rick; Edwards, Robert A

2010-06-14

The SEED integrates many publicly available genome sequences into a single resource. The database contains accurate and up-to-date annotations based on the subsystems concept that leverages clustering between genomes and other clues to accurately and efficiently annotate microbial genomes. The backend is used as the foundation for many genome annotation tools, such as the Rapid Annotation using Subsystems Technology (RAST) server for whole genome annotation, the metagenomics RAST server for random community genome annotations, and the annotation clearinghouse for exchanging annotations from different resources. In addition to a web user interface, the SEED also provides Web services based API for programmatic access to the data in the SEED, allowing the development of third-party tools and mash-ups. The currently exposed Web services encompass over forty different methods for accessing data related to microbial genome annotations. The Web services provide comprehensive access to the database back end, allowing any programmer access to the most consistent and accurate genome annotations available. The Web services are deployed using a platform independent service-oriented approach that allows the user to choose the most suitable programming platform for their application. Example code demonstrate that Web services can be used to access the SEED using common bioinformatics programming languages such as Perl, Python, and Java. We present a novel approach to access the SEED database. Using Web services, a robust API for access to genomics data is provided, without requiring large volume downloads all at once. The API ensures timely access to the most current datasets available, including the new genomes as soon as they come online.

Gamma spectrum measurement in a swimming-pool-type reactor

International Nuclear Information System (INIS)

Pla, E.

1969-01-01

After recalling the various modes of interaction of gamma rays with matter, the authors describe the design of a spectrometer for gamma energies of between 0.3 and 10 MeV. This spectrometer makes use of the Compton and pair-production effects without eliminating them. The collimator, the crystals and the electronics have been studied in detail and are described in their final form. The problem of calibrating the apparatus is then considered ; numerous graphs are given. The sensitivity of the spectrometer for different energies is determined mainly for the 'Compton effect' group. Finally, in the last part of the report, are given results of an experimental measurement of the gamma spectrum of a swimming-pool type reactor with new elements. (author) [fr

Gate Simulation of a Gamma Camera

International Nuclear Information System (INIS)

Abidi, Sana; Mlaouhi, Zohra

2008-01-01

Medical imaging is a very important diagnostic because it allows for an exploration of the internal human body. The nuclear imaging is an imaging technique used in the nuclear medicine. It is to determine the distribution in the body of a radiotracers by detecting the radiation it emits using a detection device. Two methods are commonly used: Single Photon Emission Computed Tomography (SPECT) and the Positrons Emission Tomography (PET). In this work we are interested on modelling of a gamma camera. This simulation is based on Monte-Carlo language and in particular Gate simulator (Geant4 Application Tomographic Emission). We have simulated a clinical gamma camera called GAEDE (GKS-1) and then we validate these simulations by experiments. The purpose of this work is to monitor the performance of these gamma camera and the optimization of the detector performance and the the improvement of the images quality. (Author)

Advanced gamma spectrum processing technique applied to the analysis of scattering spectra for determining material thickness

International Nuclear Information System (INIS)

Hoang Duc Tam; VNUHCM-University of Science, Ho Chi Minh City; Huynh Dinh Chuong; Tran Thien Thanh; Vo Hoang Nguyen; Hoang Thi Kieu Trang; Chau Van Tao

2015-01-01

In this work, an advanced gamma spectrum processing technique is applied to analyze experimental scattering spectra for determining the thickness of C45 heat-resistant steel plates. The single scattering peak of scattering spectra is taken as an advantage to measure the intensity of single scattering photons. Based on these results, the thickness of steel plates is determined with a maximum deviation of real thickness and measured thickness of about 4 %. Monte Carlo simulation using MCNP5 code is also performed to cross check the results, which yields a maximum deviation of 2 %. These results strongly confirm the capability of this technique in analyzing gamma scattering spectra, which is a simple, effective and convenient method for determining material thickness. (author)

Gamma ray spectrum from gravitino dark matter decay

Energy Technology Data Exchange (ETDEWEB)

Ibarra, A.; Tran, D.

2007-09-15

Gravitinos are very promising candidates for the cold dark matter of the Universe. Interestingly, to achieve a sufficiently long gravitino lifetime, R-parity conservation is not required, thus preventing any dangerous cosmological influence of the next-to-lightest supersymmetric particle. When R-parity is violated, gravitinos decay into photons and other particles with a lifetime much longer than the age of the Universe, producing a diffuse gamma ray flux with a characteristic spectrum that could be measured in future experiments, like GLAST, AMS-02 or Cherenkov telescopes. In this letter we compute the energy spectrum of photons from gravitino decay and discuss its main qualitative features. (orig.)

Development, implementation and pilot evaluation of a Web-based Virtual Patient Case Simulation environment – Web-SP

Directory of Open Access Journals (Sweden)

Boberg Jonas

2006-02-01

Full Text Available Abstract Background The Web-based Simulation of Patients (Web-SP project was initiated in order to facilitate the use of realistic and interactive virtual patients (VP in medicine and healthcare education. Web-SP focuses on moving beyond the technology savvy teachers, when integrating simulation-based education into health sciences curricula, by making the creation and use of virtual patients easier. The project strives to provide a common generic platform for design/creation, management, evaluation and sharing of web-based virtual patients. The aim of this study was to evaluate if it was possible to develop a web-based virtual patient case simulation environment where the entire case authoring process might be handled by teachers and which would be flexible enough to be used in different healthcare disciplines. Results The Web-SP system was constructed to support easy authoring, management and presentation of virtual patient cases. The case authoring environment was found to facilitate for teachers to create full-fledged patient cases without the assistance of computer specialists. Web-SP was successfully implemented at several universities by taking into account key factors such as cost, access, security, scalability and flexibility. Pilot evaluations in medical, dentistry and pharmacy courses shows that students regarded Web-SP as easy to use, engaging and to be of educational value. Cases adapted for all three disciplines were judged to be of significant educational value by the course leaders. Conclusion The Web-SP system seems to fulfil the aim of providing a common generic platform for creation, management and evaluation of web-based virtual patient cases. The responses regarding the authoring environment indicated that the system might be user-friendly enough to appeal to a majority of the academic staff. In terms of implementation strengths, Web-SP seems to fulfil most needs from course directors and teachers from various educational

GROUPING WEB ACCESS SEQUENCES uSING SEQUENCE ALIGNMENT METHOD

OpenAIRE

BHUPENDRA S CHORDIA; KRISHNAKANT P ADHIYA

2011-01-01

In web usage mining grouping of web access sequences can be used to determine the behavior or intent of a set of users. Grouping websessions is how to measure the similarity between web sessions. There are many shortcomings in traditional measurement methods. The taskof grouping web sessions based on similarity and consists of maximizing the intra-group similarity while minimizing the inter-groupsimilarity is done using sequence alignment method. This paper introduces a new method to group we...

On the high energy gamma ray spectrum and the particle production model

International Nuclear Information System (INIS)

Ohta, Itaru; Tezuka, Ikuo.

1979-01-01

A small emulsion chamber, 25 cm x 20 cm in area and 12 radiation lengths in thick, was exposed with JAL jet-cargo at an atmospheric depth of 260 g/cm 2 during 150 hrs. The gamma ray spectrum derived by combining data from X-ray films and nuclear emulsions is well represented by I sub(r) (>=Er) = (3.65 +- 0.30) x 10 -8 [E sub(r)/TeV]sup(-1.89+0.06-0.09)/cm 2 sr sec in the energy range 200 - 3,000 GeV. This result is in good agreement with those of several other groups. We discuss our data in terms of Feynman's and Koba-Nielsen-Olesen's scaling law of high energy particle production model. Interpreted in terms of an assumption of mild violation of the scaling law as x.d delta-s / delta-s indx = AE sup(2a)exp (-BE sup(a)x), our gamma ray spectrum results suggest an existence of a violation parameter of a = 0.18, which is consistent with results from gamma ray spectrum observations at great depth such as the mountain elevations. (author)

SIDECACHE: Information access, management and dissemination framework for web services.

Science.gov (United States)

Doderer, Mark S; Burkhardt, Cory; Robbins, Kay A

2011-06-14

Many bioinformatics algorithms and data sets are deployed using web services so that the results can be explored via the Internet and easily integrated into other tools and services. These services often include data from other sites that is accessed either dynamically or through file downloads. Developers of these services face several problems because of the dynamic nature of the information from the upstream services. Many publicly available repositories of bioinformatics data frequently update their information. When such an update occurs, the developers of the downstream service may also need to update. For file downloads, this process is typically performed manually followed by web service restart. Requests for information obtained by dynamic access of upstream sources is sometimes subject to rate restrictions. SideCache provides a framework for deploying web services that integrate information extracted from other databases and from web sources that are periodically updated. This situation occurs frequently in biotechnology where new information is being continuously generated and the latest information is important. SideCache provides several types of services including proxy access and rate control, local caching, and automatic web service updating. We have used the SideCache framework to automate the deployment and updating of a number of bioinformatics web services and tools that extract information from remote primary sources such as NCBI, NCIBI, and Ensembl. The SideCache framework also has been used to share research results through the use of a SideCache derived web service.

Electron-nuclear. gamma. transition spectrum of a nucleus in a multicharged atomic ion

Energy Technology Data Exchange (ETDEWEB)

Ivanov, L N; Letokhov, V S

1987-08-01

The nuclear emission of absorption spectrum of an atom possesses a set of electron satelites which are due to an alternation of the state of the electron shell. It is shown that the mechanism of formation of the satellites might be different for neutral atoms and high-charge ions. In the first case (loose electron shell) a ''shaking'' of the shell resulting from the interaction between the nucleus and ..gamma.. quantum is predominant. In the second case (rigid electron shell) the mechanism involves a direct interaction between the ..gamma.. quantum and electrons. The second mechanism is important in the case of dipole nuclear transitions and dominates at ..gamma.. quantum energies spectrum is much enriched and transitions between the fine and hyperfine structure components, transitions and transitions which do not involve a change in the electron configuration can be considered. The relative intensities of the satellites are determined by the smallest parameter ..mu../sub p//sup 2lambda/ (lambda is the nuclear transition multipole order, ..mu../sub p/ approx. 12 ..pi.. is the relative proton mass and z the core mass). In the spectrum of the plasma source the electron satellites corresponding to the ..gamma.. quantum emission and absorption lines are not overlapped by the Doppler contour of the ..gamma.. line.

Accessibility and content of individualized adult reconstructive hip and knee/musculoskeletal oncology fellowship web sites.

Science.gov (United States)

Young, Bradley L; Cantrell, Colin K; Patt, Joshua C; Ponce, Brent A

2018-06-01

Accessible, adequate online information is important to fellowship applicants. Program web sites can affect which programs applicants apply to, subsequently altering interview costs incurred by both parties and ultimately impacting rank lists. Web site analyses have been performed for all orthopaedic subspecialties other than those involved in the combined adult reconstruction and musculoskeletal (MSK) oncology fellowship match. A complete list of active programs was obtained from the official adult reconstruction and MSK oncology society web sites. Web site accessibility was assessed using a structured Google search. Accessible web sites were evaluated based on 21 previously reported content criteria. Seventy-four adult reconstruction programs and 11 MSK oncology programs were listed on the official society web sites. Web sites were identified and accessible for 58 (78%) adult reconstruction and 9 (82%) MSK oncology fellowship programs. No web site contained all content criteria and more than half of both adult reconstruction and MSK oncology web sites failed to include 12 of the 21 criteria. Several programs participating in the combined Adult Reconstructive Hip and Knee/Musculoskeletal Oncology Fellowship Match did not have accessible web sites. Of the web sites that were accessible, none contained comprehensive information and the majority lacked information that has been previously identified as being important to perspective applicants.

Guidelines for Making Web Content Accessible to All Users

Science.gov (United States)

Thompson, Terrill; Primlani, Saroj; Fiedor, Lisa

2009-01-01

The main goal of accessibility standards and guidelines is to design websites everyone can use. The "IT Accessibility Constituent Group" developed this set of draft guidelines to help EQ authors, reviewers, and staff and the larger EDUCAUSE community ensure that web content is accessible to all users, including those with disabilities. This…

Secure, web-accessible call rosters for academic radiology departments.

Science.gov (United States)

Nguyen, A V; Tellis, W M; Avrin, D E

2000-05-01

Traditionally, radiology department call rosters have been posted via paper and bulletin boards. Frequently, changes to these lists are made by multiple people independently, but often not synchronized, resulting in confusion among the house staff and technical staff as to who is on call and when. In addition, multiple and disparate copies exist in different sections of the department, and changes made would not be propagated to all the schedules. To eliminate such difficulties, a paperless call scheduling application was developed. Our call scheduling program allowed Java-enabled web access to a database by designated personnel from each radiology section who have privileges to make the necessary changes. Once a person made a change, everyone accessing the database would see the modification. This eliminates the chaos resulting from people swapping shifts at the last minute and not having the time to record or broadcast the change. Furthermore, all changes to the database were logged. Users are given a log-in name and password and can only edit their section; however, all personnel have access to all sections' schedules. Our applet was written in Java 2 using the latest technology in database access. We access our Interbase database through the DataExpress and DB Swing (Borland, Scotts Valley, CA) components. The result is secure access to the call rosters via the web. There are many advantages to the web-enabled access, mainly the ability for people to make changes and have the changes recorded and propagated in a single virtual location and available to all who need to know.

Integration of auto analysis program of gamma spectrum and software and determination of element content in sample by k-zero method

International Nuclear Information System (INIS)

Trinh Quang Vinh; Truong Thi Hong Loan; Mai Van Nhon; Huynh Truc Phuong

2014-01-01

Integrating the gamma spectrum auto-analysis program with elemental analysis software by k-zero method is the objective for many researchers. This work is the first stepin building an auto analysis program of gamma spectrum, which includes modules of reading spectrum, displaying spectrum, calibrating energy of peak, smoothing spectrum, calculating peak area and determining content of elements in sample. Then, the results from the measurements of standard samples by a low level spectrometer using HPGe detector are compared to those of other gamma spectrum auto-analysis programs. (author)

EnviroAtlas - Accessibility Characteristics in the Conterminous U.S. Web Service

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas web service includes maps that illustrate factors affecting transit accessibility, and indicators of accessibility. Accessibility measures how...

Breaking and Fixing Origin-Based Access Control in Hybrid Web/Mobile Application Frameworks.

Science.gov (United States)

Georgiev, Martin; Jana, Suman; Shmatikov, Vitaly

2014-02-01

Hybrid mobile applications (apps) combine the features of Web applications and "native" mobile apps. Like Web applications, they are implemented in portable, platform-independent languages such as HTML and JavaScript. Like native apps, they have direct access to local device resources-file system, location, camera, contacts, etc. Hybrid apps are typically developed using hybrid application frameworks such as PhoneGap. The purpose of the framework is twofold. First, it provides an embedded Web browser (for example, WebView on Android) that executes the app's Web code. Second, it supplies "bridges" that allow Web code to escape the browser and access local resources on the device. We analyze the software stack created by hybrid frameworks and demonstrate that it does not properly compose the access-control policies governing Web code and local code, respectively. Web code is governed by the same origin policy, whereas local code is governed by the access-control policy of the operating system (for example, user-granted permissions in Android). The bridges added by the framework to the browser have the same local access rights as the entire application, but are not correctly protected by the same origin policy. This opens the door to fracking attacks, which allow foreign-origin Web content included into a hybrid app (e.g., ads confined in iframes) to drill through the layers and directly access device resources. Fracking vulnerabilities are generic: they affect all hybrid frameworks, all embedded Web browsers, all bridge mechanisms, and all platforms on which these frameworks are deployed. We study the prevalence of fracking vulnerabilities in free Android apps based on the PhoneGap framework. Each vulnerability exposes sensitive local resources-the ability to read and write contacts list, local files, etc.-to dozens of potentially malicious Web domains. We also analyze the defenses deployed by hybrid frameworks to prevent resource access by foreign-origin Web content

Breaking and Fixing Origin-Based Access Control in Hybrid Web/Mobile Application Frameworks

Science.gov (United States)

Georgiev, Martin; Jana, Suman; Shmatikov, Vitaly

2014-01-01

Hybrid mobile applications (apps) combine the features of Web applications and “native” mobile apps. Like Web applications, they are implemented in portable, platform-independent languages such as HTML and JavaScript. Like native apps, they have direct access to local device resources—file system, location, camera, contacts, etc. Hybrid apps are typically developed using hybrid application frameworks such as PhoneGap. The purpose of the framework is twofold. First, it provides an embedded Web browser (for example, WebView on Android) that executes the app's Web code. Second, it supplies “bridges” that allow Web code to escape the browser and access local resources on the device. We analyze the software stack created by hybrid frameworks and demonstrate that it does not properly compose the access-control policies governing Web code and local code, respectively. Web code is governed by the same origin policy, whereas local code is governed by the access-control policy of the operating system (for example, user-granted permissions in Android). The bridges added by the framework to the browser have the same local access rights as the entire application, but are not correctly protected by the same origin policy. This opens the door to fracking attacks, which allow foreign-origin Web content included into a hybrid app (e.g., ads confined in iframes) to drill through the layers and directly access device resources. Fracking vulnerabilities are generic: they affect all hybrid frameworks, all embedded Web browsers, all bridge mechanisms, and all platforms on which these frameworks are deployed. We study the prevalence of fracking vulnerabilities in free Android apps based on the PhoneGap framework. Each vulnerability exposes sensitive local resources—the ability to read and write contacts list, local files, etc.—to dozens of potentially malicious Web domains. We also analyze the defenses deployed by hybrid frameworks to prevent resource access by foreign

The Utilization of Background Spectrum to Calibrate Gamma Spectrometry

International Nuclear Information System (INIS)

Mahrouka, M. M.; Mutawa, A. M.

2004-01-01

Many developed countries have very poor reference standards to calibrate their nuclear instrumentations or may find some difficulties to obtain a reference standard. In this work a simple way for Gamma spectrometry calibration was developed. The method depends on one reference point and additional points from the background. The two derived equations were applied to the analyses of radioactive nuclides in soil and liquid samples prepared by IAEA laboratories through AL MERA Project. The results showed the precision of the methodology used, as well as, the possibility of using some points in the background spectrum as a replacement for reference standards of Gamma spectrometry calibration. (authors)

Gamma-ray emission spectrum from thermonuclear fusion reactions without intrinsic broadening

DEFF Research Database (Denmark)

Nocente, M.; Källne, J.; Salewski, Mirko

2015-01-01

First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution instrume......First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution...... instruments. An analytical formula for the spectrum from Maxwellian plasmas, which extends to higher temperatures than the results previously available in the literature, has been derived and used to discuss the assumptions and limitations of earlier models. In case of radio-frequency injection, numerical...... results based on a Monte Carlo method are provided, focusing in particular on improved relations between the peak shift and width from the reaction and the temperature of protons accelerated by radio-frequency heating.The results presented in this paper significantly improve the accuracy of diagnostic...

The self-absorption effect of gamma rays in 239Pu

International Nuclear Information System (INIS)

Hsiaohua Hsu

1989-01-01

Nuclear materials assay with gamma-ray spectrum measurement is a well-established method for safeguards. However, for a thick source, the self-absorption of characteristic low-energy gamma rays has been a handicap to accurate assay. The author has carried out Monte Carlo simulations to study this effect using the 239 Pu α-decay gamma-ray spectrum as an example. The thickness of a plutonium metal source can be considered a function of gamma-ray intensity ratios. In a practical application, gamma-ray intensity ratios can be obtained from a measured spectrum. With the help of calculated curves, scientists can find the source thickness and make corrections to gamma-ray intensities, which then lead to an accurate quantitative determination of radioactive isotopes in the material

SWS: accessing SRS sites contents through Web Services

OpenAIRE

Romano, Paolo; Marra, Domenico

2008-01-01

Background Web Services and Workflow Management Systems can support creation and deployment of network systems, able to automate data analysis and retrieval processes in biomedical research. Web Services have been implemented at bioinformatics centres and workflow systems have been proposed for biological data analysis. New databanks are often developed by taking into account these technologies, but many existing databases do not allow a programmatic access. Only a fraction of available datab...

MOXE: An X-ray all-sky monitor for Soviet Spectrum-X-Gamma Mission

Science.gov (United States)

Priedhorsky, W.; Fenimore, E. E.; Moss, C. E.; Kelley, R. L.; Holt, S. S.

1989-01-01

A Monitoring Monitoring X-Ray Equipment (MOXE) is being developed for the Soviet Spectrum-X-Gamma Mission. MOXE is an X-ray all-sky monitor based on array of pinhole cameras, to be provided via a collaboration between Goddard Space Flight Center and Los Alamos National Laboratory. The objectives are to alert other observers on Spectrum-X-Gamma and other platforms of interesting transient activity, and to synoptically monitor the X-ray sky and study long-term changes in X-ray binaries. MOXE will be sensitive to sources as faint as 2 milliCrab (5 sigma) in 1 day, and cover the 2 to 20 KeV band.

Measurement of Gamma Spectrum at domestic Nuclear Power Plant with CZT Semiconductor Detector

Energy Technology Data Exchange (ETDEWEB)

Kon, Kang Seo; Yoon, Kang Hwa; Lee, Byoung Il; Kim, Jeong In [KHNP, Radiation Health Research Institute, Seoul (Korea, Republic of)

2013-10-15

In this study we monitored gamma spectrum for young S/G to see difference of the detected nuclides between old and young S/G. The detected source terms were the same for all measurement points. There is not comparison of quantity among the nuclides. The program which analyzes gamma spectrum to calculate activity and dose rate is under developing. We expect it will be done by end of this year. In this study we could see the difference of detected nuclides between old and new S/G for the first time whereas last measurement has significant meaning in that the measurement was taken for the first time all over country. Monitoring sources terms at Nuclear Power Plant(NPP) is important to aggressive ALARA activities and evaluation of exposure of workers. EDF (Electricite de France) and AEP (American Electric Power) conduct monitoring source terms using by CZT semiconductor detector. CZT is different from HPGe in that it does not need any cooling system at room temperature, it has good energy resolution and it can be made portable type easily. For these reason CZT is used in various fields commercially to measure gamma ray and therefore KHNP(Korea Hydro and Nuclear Power Co., LTD) RHRI(Radiation Health Research Institute) has been measuring gamma spectrum at domestic NPP last spring. We had have presented the first result through the last Transactions of the Korean Nuclear Society Spring Meeting for old S/G(Steam Generator)

Gamma ray shielding: a web based interactive program

International Nuclear Information System (INIS)

Subbaiah, K.V.; Senthi Kumar, C.; Sarangapani, R.

2005-01-01

A web based interactive computing program is developed using java for quick assessment of Gamma Ray shielding problems. The program addresses usually encountered source geometries like POINT, LINE, CYLINDRICAL, ANNULAR, SPHERICAL, BOX, followed by 'SLAB' shield configurations. The calculation is based on point kernel technique. The source points are randomly sampled within the source volume. From each source point, optical path traversed in the source and shield media up to the detector location is estimated to calculate geometrical and material attenuations, and then corresponding buildup factor is obtained, which accounts for scattered contribution. Finally, the dose rate for entire source is obtained by summing over all sampled points. The application allows the user to select one of the seven regular geometrical bodies and provision exist to give source details such as emission energies, intensities, physical dimensions and material composition. Similar provision is provided to specify shield slab details. To aid the user, atomic numbers, densities, standard build factor materials and isotope list with respective emission energies and intensity for ready reference are given in dropdown combo boxes. Typical results obtained from this program are validated against existing point kernel gamma ray shielding codes. Additional facility is provided to compute fission product gamma ray source strengths based on the fuel type, burn up and cooling time. Plots of Fission product gamma ray source strengths, Gamma ray cross-sections and buildup factors can be optionally obtained, which enable the user to draw inference on the computed results. It is expected that this tool will be handy to all health physicists and radiological safety officers as it will be available on the internet. (author)

Experiences With Area Specific Spectrum Stripping of Nai(Tl) Gamma Spectra

DEFF Research Database (Denmark)

Aage, Helle Karina; Korsbech, Uffe C C; Bargholz, Kim

2006-01-01

Abstract Processing of airborne and carborne gamma-ray spectra (AGS and CGS) often includes the stripping (elimination) of the signals from natural radioactivity. Hereby the net result becomes the signals from manmade radioactivity or other radiation anomalies. The parameters needed for spectrum ...

Planetary gamma-ray spectroscopy: the effects of hydrogen absorption cross-section of the gamma-ray spectrum

International Nuclear Information System (INIS)

Lapides, J.R.

1981-01-01

The gamma-ray spectroscopy of planet surfaces is one of several possible methods that are useful in determining the elemental composition of planet surfaces from orbiting spacecraft. This has been demonstrated on the Apollos 15 and 16 missions as well as the Soviet Mars-5 mission. Planetary gamma-ray emission is primarily the result of natural radioactive decay and cosmic-ray and solar-flare-induced nuclear reactions. Secondary neutron reactions play a large role in the more intense gamma-ray emission. The technique provides information on the elemental composition of the top few tens of centimeters of the planet surface. Varying concentrations of hydrogen and compositional variations that alter the macroscopic thermal-neutron absorption cross section have a significant effect on the neutron flux in the planet surface and therefore also on the gamma-ray emission from the surface. These effects have been systematically studied for a wide range of possible planetary compositions that include Mercury, the moon, Mars, the comets, and the asteroids. The problem of the Martian atmosphere was also investigated. The results of these calculations, in which both surface neutron fluxes and gamma-ray emission fluxes were determined, were used to develop general procedures for obtaining planet compositions from the gamma-ray spectrum. Several changes have been suggested for reanalyzing the Apollos 15 and 16 gamma-ray results. In addition, procedures have been suggested that can be applied to neutron-gamma techniques in mineral and oil exploration

Inclusão digital via acessibilidade web | Digital inclusion via web accessibility

Directory of Open Access Journals (Sweden)

Cesar Augusto Cusin

2009-03-01

Full Text Available Resumo A natureza atual da web, que destaca a participação colaborativa dos usuários em diversos ambientes informacionais digitais, conduz ao desenvolvimento de diretrizes que enfocam a arquitetura da informação digital inclusiva para diferentes públicos nas mais diversas ambiências informacionais. A pesquisa propõe e objetiva um ambiente informacional digital inclusivo, visando apontar os elementos de acessibilidade que permitam a promoção da inclusão informacional digital, de forma a destacar os referenciais da Arquitetura da Informação Digital, de recomendações internacionais, com o olhar da Ciência da Informação e das novas tecnologias de informação e comunicação (TIC. Palavras-chave inclusão digital; web; acessibilidade; ciência da informação; arquitetura da informação. Abstract The current nature of the web, which highlights the collaborative participation of users in various digital informational environments, leads to the development of guidelines that focus on the digital inclusive information architecture for different audiences in diverse informational environments. The study proposes an inclusive digital information environment, aiming to establish the elements of accessibility that  enable the promotion of digital inclusion information in order to highlight the references of digital information architecture, the international recommendations, with the perspective of Information Science and the new information and communication technologies (ICT. Keywords digital inclusion; web; accessibility; information science; information architecture.

EntrezAJAX: direct web browser access to the Entrez Programming Utilities

Directory of Open Access Journals (Sweden)

Pallen Mark J

2010-06-01

Full Text Available Abstract Web applications for biology and medicine often need to integrate data from Entrez services provided by the National Center for Biotechnology Information. However, direct access to Entrez from a web browser is not possible due to 'same-origin' security restrictions. The use of "Asynchronous JavaScript and XML" (AJAX to create rich, interactive web applications is now commonplace. The ability to access Entrez via AJAX would be advantageous in the creation of integrated biomedical web resources. We describe EntrezAJAX, which provides access to Entrez eUtils and is able to circumvent same-origin browser restrictions. EntrezAJAX is easily implemented by JavaScript developers and provides identical functionality as Entrez eUtils as well as enhanced functionality to ease development. We provide easy-to-understand developer examples written in JavaScript to illustrate potential uses of this service. For the purposes of speed, reliability and scalability, EntrezAJAX has been deployed on Google App Engine, a freely available cloud service. The EntrezAJAX webpage is located at http://entrezajax.appspot.com/

A System for Web-based Access to the HSOS Database

Science.gov (United States)

Lin, G.

Huairou Solar Observing Station's (HSOS) magnetogram and dopplergram are world-class instruments. Access to their data has opened to the world. Web-based access to the data will provide a powerful, convenient tool for data searching and solar physics. It is necessary that our data be provided to users via the Web when it is opened to the world. In this presentation, the author describes general design and programming construction of the system. The system will be generated by PHP and MySQL. The author also introduces basic feature of PHP and MySQL.

A Web Service for File-Level Access to Disk Images

Directory of Open Access Journals (Sweden)

Sunitha Misra

2014-07-01

Full Text Available Digital forensics tools have many potential applications in the curation of digital materials in libraries, archives and museums (LAMs. Open source digital forensics tools can help LAM professionals to extract digital contents from born-digital media and make more informed preservation decisions. Many of these tools have ways to display the metadata of the digital media, but few provide file-level access without having to mount the device or use complex command-line utilities. This paper describes a project to develop software that supports access to the contents of digital media without having to mount or download the entire image. The work examines two approaches in creating this tool: First, a graphical user interface running on a local machine. Second, a web-based application running in web browser. The project incorporates existing open source forensics tools and libraries including The Sleuth Kit and libewf along with the Flask web application framework and custom Python scripts to generate web pages supporting disk image browsing.

The Effects of a Dynamic Spectrum Access Overlay in LTE-Advanced Networks

Energy Technology Data Exchange (ETDEWEB)

Juan D. Deaton; Ryan E. lrwin; Luiz A. DaSilva

2011-05-01

As early as 2014, wireless network operators spectral capacity will be overwhelmed by a data tsunami brought on by new devices and applications. To augment spectral capacity, operators could deploy a Dynamic Spectrum Access (DSA) overlay. In the light of the many planned Long Term Evolution (LTE) network deployments, the affects of a DSA overlay have not been fully considered into the existing LTE standards. Coalescing many different aspects of DSA, this paper develops the Spectrum Accountability (SA) framework. The SA framework defines specific network element functionality, protocol interfaces, and signaling flow diagrams for LTE to support service requests and enforce rights of responsibilities of primary and secondary users, respectively. We also include a network simulation to quantify the benefits of using DSA channels to augment capacity. Based on our simulation we show that, network operators can benefit up to %40 increase in operating capacity when sharing DSA bands to augment spectral capacity. With our framework, this paper could serve as an guide in developing future LTE network standards that include DSA.

Evaluation of peak-fitting software for gamma spectrum analysis

International Nuclear Information System (INIS)

Zahn, Guilherme S.; Genezini, Frederico A.; Moralles, Mauricio

2009-01-01

In all applications of gamma-ray spectroscopy, one of the most important and delicate parts of the data analysis is the fitting of the gamma-ray spectra, where information as the number of counts, the position of the centroid and the width, for instance, are associated with each peak of each spectrum. There's a huge choice of computer programs that perform this type of analysis, and the most commonly used in routine work are the ones that automatically locate and fit the peaks; this fit can be made in several different ways - the most common ways are to fit a Gaussian function to each peak or simply to integrate the area under the peak, but some software go far beyond and include several small corrections to the simple Gaussian peak function, in order to compensate for secondary effects. In this work several gamma-ray spectroscopy software are compared in the task of finding and fitting the gamma-ray peaks in spectra taken with standard sources of 137 Cs, 60 Co, 133 Ba and 152 Eu. The results show that all of the automatic software can be properly used in the task of finding and fitting peaks, with the exception of GammaVision; also, it was possible to verify that the automatic peak-fitting software did perform as well as - and sometimes even better than - a manual peak-fitting software. (author)

Accessibility of dynamic web applications with emphasis on visually impaired users

Directory of Open Access Journals (Sweden)

Kingsley Okoye

2014-09-01

Full Text Available As the internet is fast migrating from static web pages to dynamic web pages, the users with visual impairment find it confusing and challenging when accessing the contents on the web. There is evidence that dynamic web applications pose accessibility challenges for the visually impaired users. This study shows that a difference can be made through the basic understanding of the technical requirement of users with visual impairment and addresses a number of issues pertinent to the accessibility needs for such users. We propose that only by designing a framework that is structurally flexible, by removing unnecessary extras and thereby making every bit useful (fit-for-purpose, will visually impaired users be given an increased capacity to intuitively access e-contents. This theory is implemented in a dynamic website for the visually impaired designed in this study. Designers should be aware of how the screen reading software works to enable them make reasonable adjustments or provide alternative content that still corresponds to the objective content to increase the possibility of offering faultless service to such users. The result of our research reveals that materials can be added to a content repository or re-used from existing ones by identifying the content types and then transforming them into a flexible and accessible one that fits the requirements of the visually impaired through our method (no-frill + agile methodology rather than computing in advance or designing according to a given specification.

A novel natural environment background model for Monte Carlo simulation and its application in the simulation of anticoincidence measurement

International Nuclear Information System (INIS)

Li, Sangang; Wang, Lei; Cheng, Yi; Tuo, Xianguo; Liu, Mingzhe; Yao, Fuliang; Leng, Fengqing; Cheng, Yuanyuan; Cai, Ting; Zhou, Yan

2016-01-01

This study proposes a novel natural environment background model by modeling brief environment conditions. It uses Geant4 program to simulate decays of "2"3"8U, "2"3"2Th, and "4"0K in soil and obtains compositions of different-energy gamma rays in the natural environment background. The simulated gamma spectrum of the natural environment background agrees well with the experimental spectrum, particularly above 250 keV. The model is used in the simulation of anticoincidence measurement, indicating that the natural environment background can be decreased by approximately 88%, and the Compton attenuation factor is 2.22. The simulation of anticoincidence measurement can improve the minimum detectable activity (MDA) of the detection system. - Highlights: • This study proposes a novel natural environment background model by simulating decays of "2"3"8U, "2"3"2Th, and "4"0K in soil. • The simulated gamma spectrum of the natural environment background agrees well with the experimental spectrum, particularly above 250 keV. • The proposed environment background model is applied to study the properties of anticoincidence detector.

The theoretical study of full spectrum analysis method for airborne gamma-ray spectrometric data

International Nuclear Information System (INIS)

Ni Weichong

2011-01-01

Spectra of airborne gamma-ray spectrometry was found to be the synthesis of spectral components of radioelement sources by analyzing the constitution of radioactive sources for airborne gamma-ray spectrometric survey and establishing the models of gamma-ray measurement. The mathematical equation for analysising airborne gamma-ray full spectrometric data can be expressed into matrix and related expansions were developed for the mineral resources exploration, environmental radiation measurement, nuclear emergency monitoring, and so on. Theoretical study showed that the atmospheric radon could be directly computed by airborne gamma-ray spectrometric data with full spectrum analysis without the use of the accessional upward-looking detectors. (authors)

Building Accessible Educational Web Sites: The Law, Standards, Guidelines, Tools, and Lessons Learned

Science.gov (United States)

Liu, Ye; Palmer, Bart; Recker, Mimi

2004-01-01

Professional education is increasingly facing accessibility challenges with the emergence of webbased learning. This paper summarizes related U.S. legislation, standards, guidelines, and validation tools to make web-based learning accessible for all potential learners. We also present lessons learned during the implementation of web accessibility…

Procedures can be learned on the Web: a randomized study of ultrasound-guided vascular access training.

Science.gov (United States)

Chenkin, Jordan; Lee, Shirley; Huynh, Thien; Bandiera, Glen

2008-10-01

Web-based learning has several potential advantages over lectures, such as anytime-anywhere access, rich multimedia, and nonlinear navigation. While known to be an effective method for learning facts, few studies have examined the effectiveness of Web-based formats for learning procedural skills. The authors sought to determine whether a Web-based tutorial is at least as effective as a didactic lecture for learning ultrasound-guided vascular access (UGVA). Participating staff emergency physicians (EPs) and junior emergency medicine (EM) residents with no UGVA experience completed a precourse test and were randomized to either a Web-based or a didactic group. The Web-based group was instructed to use an online tutorial and the didactic group attended a lecture. Participants then practiced on simulators and live models without any further instruction. Following a rest period, participants completed a four-station objective structured clinical examination (OSCE), a written examination, and a postcourse questionnaire. Examination results were compared using a noninferiority data analysis with a 10% margin of difference. Twenty-one residents and EPs participated in the study. There were no significant differences in mean OSCE scores (absolute difference = -2.8%; 95% confidence interval [CI] = -9.3% to 3.8%) or written test scores (absolute difference = -1.4%; 95% CI = -7.8% to 5.0%) between the Web group and the didactic group. Both groups demonstrated similar improvements in written test scores (26.1% vs. 25.8%; p = 0.95). Ninety-one percent (10/11) of the Web group and 80% (8/10) of the didactic group participants found the teaching format to be effective (p = 0.59). Our Web-based tutorial was at least as effective as a traditional didactic lecture for teaching the knowledge and skills essential for UGVA. Participants expressed high satisfaction with this teaching technology. Web-based teaching may be a useful alternative to didactic teaching for learning procedural

Gamma-ray pulse height spectrum analysis on systems with multiple Ge detectors using spectrum summing

Energy Technology Data Exchange (ETDEWEB)

Killian, E.W. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

1997-11-01

A technique has been developed at the Idaho National Engineering Laboratory to sum high resolution gamma-ray pulse spectra from systems with multiple Ge detectors. Lockheed Martin Idaho Technologies Company operates a multi-detector spectrometer configuration at the Stored Waste Examination Pilot Plant facility which is used to characterize the radionuclide contents in waste drums destined for shipment to Waste Isolation Pilot Plant. This summing technique was developed to increase the sensitivity of the system, reduce the count times required to properly quantify the radio-nuclides and provide a more consistent methodology for combining data collected from multiple detectors. In spectrometer systems with multiple detectors looking at non homogeneous waste forms it is often difficult to combine individual spectrum analysis results from each detector to obtain a meaningful result for the total waste container. This is particularly true when the counting statistics in each individual spectrum are poor. The spectrum summing technique adds the spectra collected by each detector into a single spectrum which has better counting statistics than each individual spectrum. A normal spectral analysis program can then be used to analyze the sum spectrum to obtain radio-nuclide values which have smaller errors and do not have to be further manipulated to obtain results for the total waste container. 2 refs., 2 figs.

Spectrum access and management for cognitive radio networks

CERN Document Server

2017-01-01

This book presents cutting-edge research contributions that address various aspects of network design, optimization, implementation, and application of cognitive radio technologies. It demonstrates how to make better utilization of the available spectrum, cognitive radios and spectrum access to achieve effective spectrum sharing between licensed and unlicensed users. The book provides academics and researchers essential information on current developments and future trends in cognitive radios for possible integration with the upcoming 5G networks. In addition, it includes a brief introduction to cognitive radio networks for newcomers to the field.

Study of mixed programming gamma spectrum acquisition method based on MSP430F4618

International Nuclear Information System (INIS)

Li Yuezhong; Tang Bin; Zhang Zhongliang; Xie Xiaolin

2012-01-01

In order to reduce the hand-held gamma spectrometer measurements dead time and to complete the low-voltage and low-power design, the spectrum signal acquisition circuit is constituted by the ultra-low power microcontroller MSP430F4618 and its external signal conditioning circuit, anti-coincidence circuit interface and its on-chip sample hold and A/D converter. C language programming and assembly one have been used together. The sample hold and A/D conversion and spectrum acquisition programming is accomplished by assembly language, and the system monitoring and task scheduler designing is accomplished by C language programming. The handhold gamma spectrometer power supply, which just uses two No.5 rechargeable batteries, is designed by high-efficiency DC-DC circuit. The prototype gamma spectrometer is developed by the method, and its testing shows that the implementation of spectrum acquisition time is shorten by twice to 3 times, that is, the dead measurement can be reduced; and the machine operating current does not exceed 150 mA. By using two 2400 mAh No.5 rechargeable battery, the machine can work continuously more than 10 hours, and it can meet the application requirements. (authors)

Web 2.0 Sites for Collaborative Self-Access: The Learning Advisor vs. Google®

Directory of Open Access Journals (Sweden)

Craig D. Howard

2011-09-01

Full Text Available While Web 2.0 technologies provide motivated, self-access learners with unprecedented opportunities for language learning, Web 2.0 designs are not of universally equal value for learning. This article reports on research carried out at Indiana University Bloomington using an empirical method to select websites for self-access language learning. Two questions related to Web 2.0 recommendations were asked: (1 How do recommended Web 2.0 sites rank in terms of interactivity features? (2 How likely is a learner to find highly interactive sites on their own? A list of 20 sites used for supplemental and self-access activities in language programs at five universities was compiled and provided the initial data set. Purposive sampling criteria revealed 10 sites truly represented Web 2.0 design. To address the first question, a feature analysis was applied (Herring, The international handbook of internet research. Berlin: Springer, 2008. An interactivity framework was developed from previous research to identify Web 2.0 design features, and sites were ranked according to feature quantity. The method used to address the second question was an interconnectivity analysis that measured direct and indirect interconnectivity within Google results. Highly interactive Web 2.0 sites were not prominent in Google search results, nor were they often linked via third party sites. It was determined that, using typical keywords or searching via blogs and recommendation sites, self-access learners were highly unlikely to find the most promising Web 2.0 sites for language learning. A discussion of the role of the learning advisor in guiding Web 2.0 collaborative self-access, as well as some strategic short cuts to quick analysis, conclude the article.

Spectrum of the isotropic diffuse gamma-ray emission derived from first-year Fermi Large Area Telescope data.

Science.gov (United States)

Abdo, A A; Ackermann, M; Ajello, M; Atwood, W B; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Baughman, B M; Bechtol, K; Bellazzini, R; Berenji, B; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Bregeon, J; Brez, A; Brigida, M; Bruel, P; Burnett, T H; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Cavazzuti, E; Cecchi, C; Celik, O; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L R; Conrad, J; Cutini, S; Dermer, C D; de Angelis, A; de Palma, F; Digel, S W; Di Bernardo, G; do Couto e Silva, E; Drell, P S; Drlica-Wagner, A; Dubois, R; Dumora, D; Farnier, C; Favuzzi, C; Fegan, S J; Focke, W B; Fortin, P; Frailis, M; Fukazawa, Y; Funk, S; Fusco, P; Gaggero, D; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giommi, P; Giordano, F; Glanzman, T; Godfrey, G; Grenier, I A; Grondin, M-H; Grove, J E; Guillemot, L; Guiriec, S; Gustafsson, M; Hanabata, Y; Harding, A K; Hayashida, M; Hughes, R E; Itoh, R; Jackson, M S; Jóhannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Kamae, T; Katagiri, H; Kataoka, J; Kawai, N; Kerr, M; Knödlseder, J; Kocian, M L; Kuehn, F; Kuss, M; Lande, J; Latronico, L; Lemoine-Goumard, M; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Madejski, G M; Makeev, A; Mazziotta, M N; McConville, W; McEnery, J E; Meurer, C; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nolan, P L; Norris, J P; Nuss, E; Ohsugi, T; Omodei, N; Orlando, E; Ormes, J F; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Pesce-Rollins, M; Piron, F; Porter, T A; Rainò, S; Rando, R; Razzano, M; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Rochester, L S; Rodriguez, A Y; Roth, M; Ryde, F; Sadrozinski, H F-W; Sanchez, D; Sander, A; Saz Parkinson, P M; Scargle, J D; Sellerholm, A; Sgrò, C; Shaw, M S; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Starck, J-L; Strickman, M S; Strong, A W; Suson, D J; Tajima, H; Takahashi, H; Takahashi, T; Tanaka, T; Thayer, J B; Thayer, J G; Thompson, D J; Tibaldo, L; Torres, D F; Tosti, G; Tramacere, A; Uchiyama, Y; Usher, T L; Vasileiou, V; Vilchez, N; Vitale, V; Waite, A P; Wang, P; Winer, B L; Wood, K S; Ylinen, T; Ziegler, M

2010-03-12

We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.

Web accessibility practical advice for the library and information professional

CERN Document Server

Craven, Jenny

2008-01-01

Offers an introduction to web accessibility and usability for information professionals, offering advice on the concerns relevant to library and information organizations. This book can be used as a resource for developing staff training and awareness activities. It will also be of value to website managers involved in web design and development.

Gamma spectrum analysis including NAA with SAMPO for Windows

International Nuclear Information System (INIS)

Aarnio, P.A.; Nikkinen, M.T.; Routti, J.T.

1995-01-01

SAMPO for Windows is a high performance gamma spectrum analysis program. All the measurement, analysis and NAA phases can be done either under full interactive use control or user defined tasks can be used for automated measurement and analysis sequences including control of MCAs and sample changers. High resolution gamma-ray spectroscopy together with the possibility to resolve complex multiplets with high accuracy makes SAMPO very suitable for INAA. On the other hand, the possibility to automate analysis sequences allows it use effectively also in all routine NAA measurements. NAA in SAMPO is accomplished using comparative methods. Spectra of standards, flux monitors, controls and actual samples are analyzed normally to obtain the peak areas which are optionally corrected for decay. In the comparison the flux monitor results are used to correct for variations in the effective neutron flux. An optional irradiation position correction can also be applied. The controls are used to alarm for possible deviations in the results. The sophisticated spectrum analysis methods used together with the comparative NAA and monitors give accurate results limited by the systematic effects only. The Windows environment provides ease of use and further processing power is available through the interface to expert system identification of nuclides. (author) 19 refs.; 1 tab

Hand Society and Matching Program Web Sites Provide Poor Access to Information Regarding Hand Surgery Fellowship.

Science.gov (United States)

Hinds, Richard M; Klifto, Christopher S; Naik, Amish A; Sapienza, Anthony; Capo, John T

2016-08-01

The Internet is a common resource for applicants of hand surgery fellowships, however, the quality and accessibility of fellowship online information is unknown. The objectives of this study were to evaluate the accessibility of hand surgery fellowship Web sites and to assess the quality of information provided via program Web sites. Hand fellowship Web site accessibility was evaluated by reviewing the American Society for Surgery of the Hand (ASSH) on November 16, 2014 and the National Resident Matching Program (NRMP) fellowship directories on February 12, 2015, and performing an independent Google search on November 25, 2014. Accessible Web sites were then assessed for quality of the presented information. A total of 81 programs were identified with the ASSH directory featuring direct links to 32% of program Web sites and the NRMP directory directly linking to 0%. A Google search yielded direct links to 86% of program Web sites. The quality of presented information varied greatly among the 72 accessible Web sites. Program description (100%), fellowship application requirements (97%), program contact email address (85%), and research requirements (75%) were the most commonly presented components of fellowship information. Hand fellowship program Web sites can be accessed from the ASSH directory and, to a lesser extent, the NRMP directory. However, a Google search is the most reliable method to access online fellowship information. Of assessable programs, all featured a program description though the quality of the remaining information was variable. Hand surgery fellowship applicants may face some difficulties when attempting to gather program information online. Future efforts should focus on improving the accessibility and content quality on hand surgery fellowship program Web sites.

Usability and Accessibility of Air Force Intranet Web Sites

National Research Council Canada - National Science Library

Bentley, Richard S

2006-01-01

.... This research effort seeks to establish an understanding of how well common practice usability design principles and government mandated accessibility guidelines are followed by Air Force intranet web sites...

Spectrum access games for cognitive radio networks

CSIR Research Space (South Africa)

Masonta, MT

2010-09-01

Full Text Available received a wide acceptance in next generation and intelligent wireless communication systems. In this paper the authors make use of game theory approach to model and analyze cognitive radio networks in order to allow dynamic spectrum access in broadband...

Gamma-ray Full Spectrum Analysis for Environmental Radioactivity by HPGe Detector

Science.gov (United States)

Jeong, Meeyoung; Lee, Kyeong Beom; Kim, Kyeong Ja; Lee, Min-Kie; Han, Ju-Bong

2014-12-01

Odyssey, one of the NASA¡¯s Mars exploration program and SELENE (Kaguya), a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS) for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe) detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA) method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA) method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of 40K, 232Th and 238U in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl) and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

Gamma-ray Full Spectrum Analysis for Environmental Radioactivity by HPGe Detector

Directory of Open Access Journals (Sweden)

Meeyoung Jeong

2014-12-01

Full Text Available Odyssey, one of the NASA’s Mars exploration program and SELENE (Kaguya, a Japanese lunar orbiting spacecraft have a payload of Gamma-Ray Spectrometer (GRS for analyzing radioactive chemical elements of the atmosphere and the surface. In these days, gamma-ray spectroscopy with a High-Purity Germanium (HPGe detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the Earth. The energy spectra obtained by the HPGe detectors have been generally analyzed by means of the Window Analysis (WA method. In this method, activity concentrations are determined by using the net counts of energy window around individual peaks. Meanwhile, an alternative method, the so-called Full Spectrum Analysis (FSA method uses count numbers not only from full-absorption peaks but from the contributions of Compton scattering due to gamma-rays. Consequently, while it takes a substantial time to obtain a statistically significant result in the WA method, the FSA method requires a much shorter time to reach the same level of the statistical significance. This study shows the validation results of FSA method. We have compared the concentration of radioactivity of 40K, 232Th and 238U in the soil measured by the WA method and the FSA method, respectively. The gamma-ray spectrum of reference materials (RGU and RGTh, KCl and soil samples were measured by the 120% HPGe detector with cosmic muon veto detector. According to the comparison result of activity concentrations between the FSA and the WA, we could conclude that FSA method is validated against the WA method. This study implies that the FSA method can be used in a harsh measurement environment, such as the gamma-ray measurement in the Moon, in which the level of statistical significance is usually required in a much shorter data acquisition time than the WA method.

Deficiency in Monte Carlo simulations of coupled neutron-gamma-ray fields

NARCIS (Netherlands)

Maleka, Peane P.; Maucec, Marko; de Meijer, Robert J.

2011-01-01

The deficiency in Monte Carlo simulations of coupled neutron-gamma-ray field was investigated by benchmarking two simulation codes with experimental data. Simulations showed better correspondence with the experimental data for gamma-ray transport only. In simulations, the neutron interactions with

Collaboration system for simulation using commercial Web3D

International Nuclear Information System (INIS)

Okamoto, Koji; Ohkubo, Kohei

2004-01-01

The Web-3D system has been widely used in the internet. It can show the 3D environment easily and friendly. In order to develop the network collaboration system, the Web-3D system is used as the front end of the visualization tool. The 3D geometries have been transferred from the server using HTTP with the viewpoint, one of the commercialized Web-3D. The simulation results are directly transferred to the client using the TCP/IP socket with JAVA. The viewpoint can be controlled by the JAVA, so the transferred simulation data are displayed on the web, in real-time. The multi-client system enables the visualization of the real-time simulation results with remote site. The same results are shown on the remote web site, simultaneously. This means the remote collaboration can be achievable for the real-time simulation. Also, the system has the feedback system, which control the simulation parameter remotely. In this prototype system, the key feature of the collaboration system are discussed using the viewpoint as the frontend. (author)

An interactive gamma-ray burst educational text for the world wide-web

Science.gov (United States)

Horack, John M.; Rizvi, Sherene; Friend, Labraunna

1996-08-01

In order to strengthen education and scientific literacy among the general public, it is important to communicate the results NASA has obtained, as well as the excitement of doing world-class science. The NASA Strategic Plan specifically mandates that new opportunities and pathways be found to disseminate scientific information for consumption by the general public. We therefore announce the release of A Major League Puzzle, an interactive educational text for the WWW. A Major League Puzzle is a seven-chapter introduction to the gamma-ray burst phenomenon presented to the user through the paradigms of baseball. This resource is intended for the general public who are interested in but have not received specific training in the sciences, and is targeted to reach students at the high-school level. Using a Web-browser program such as Netscape or Mosaic, A Major League Puzzle can be accessed at ``http://wwwssl.msfc.nasa.gov/ssl/pad/astro/batse/foreword.htm.'' This work is one product of the Summer High School Apprenticeship Research Program (SHARP) conducted at the Marshall Space Flight Center in the Summer of 1995.

Monte Carlo Simulations of Ultra-High Energy Resolution Gamma Detectors for Nuclear Safeguards

International Nuclear Information System (INIS)

Robles, A.; Drury, O.B.; Friedrich, S.

2009-01-01

Ultra-high energy resolution superconducting gamma-ray detectors can improve the accuracy of non-destructive analysis for unknown radioactive materials. These detectors offer an order of magnitude improvement in resolution over conventional high purity germanium detectors. The increase in resolution reduces errors from line overlap and allows for the identification of weaker gamma-rays by increasing the magnitude of the peaks above the background. In order to optimize the detector geometry and to understand the spectral response function Geant4, a Monte Carlo simulation package coded in C++, was used to model the detectors. Using a 1 mm 3 Sn absorber and a monochromatic gamma source, different absorber geometries were tested. The simulation was expanded to include the Cu block behind the absorber and four layers of shielding required for detector operation at 0.1 K. The energy spectrum was modeled for an Am-241 and a Cs-137 source, including scattering events in the shielding, and the results were compared to experimental data. For both sources the main spectral features such as the photopeak, the Compton continuum, the escape x-rays and the backscatter peak were identified. Finally, the low energy response of a Pu-239 source was modeled to assess the feasibility of Pu-239 detection in spent fuel. This modeling of superconducting detectors can serve as a guide to optimize the configuration in future spectrometer designs.

Radio resource allocation and dynamic spectrum access

CERN Document Server

Benmammar , Badr

2013-01-01

We are currently witnessing an increase in telecommunications norms and standards given the recent advances in this field. The increasing number of normalized standards paves the way for an increase in the range of services available for each consumer. Moreover, the majority of available radio frequencies have already been allocated. This explains the emergence of cognitive radio (CR) - the sharing of the spectrum between a primary user and a secondary user.In this book, we will present the state of the art of the different techniques for spectrum access using cooperation and competit

Reproducibility of (n,γ) gamma ray spectrum in Pb under different ENDF/B releases

Energy Technology Data Exchange (ETDEWEB)

Kebwaro, J.M., E-mail: jeremiahkebwaro@gmail.com [Department of Physical Sciences, Karatina University, P.O. Box 1957-10101, Karatina (Kenya); He, C.H.; Zhao, Y.L. [School of Nuclear Science and Technology, Xian Jiaotong University, Xian, Shaanxi 710049 (China)

2016-04-15

Radiative capture reactions are of interest in shielding design and other fundamental research. In this study the reproducibility of (n,γ) reactions in Pb when cross-section data from different ENDF/B releases are used in the Monte-Carlo code, MCNP, was investigated. Pb was selected for this study because it is widely used in shielding applications where capture reactions are likely to occur. Four different neutron spectra were declared as source in the MCNP model which consisted of a simple spherical geometry. The gamma ray spectra due to the capture reactions were recorded at 10 cm from the center of the sphere. The results reveal that the gamma ray spectrum produced by ENDF/B-V is in reasonable agreement with that produced when ENDF/B-VI.6 is used. However the spectrum produced by ENDF/B-VII does not reveal any primary gamma rays in the higher energy region (E > 3 MeV). It is further observed that the intensities of the capture gamma rays produced when various releases are used differ by a some margin showing that the results are not reproducible. The generated spectra also vary with the spectrum of the source neutrons. The discrepancies observed among various ENDF/B releases could raise concerns to end users and need to be addressed properly during benchmarking calculations before the next release. The evaluation from ENDF to ACE format that is supplied with MCNP should also be examined because errors might have arisen during the evaluation.

Simulated gamma-ray pulse profile of the Crab pulsar with the Cherenkov Telescope Array

Science.gov (United States)

Burtovoi, A.; Zampieri, L.

2016-07-01

We present simulations of the very high energy (VHE) gamma-ray light curve of the Crab pulsar as observed by the Cherenkov Telescope Array (CTA). The CTA pulse profile of the Crab pulsar is simulated with the specific goal of determining the accuracy of the position of the interpulse. We fit the pulse shape obtained by the Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) telescope with a three-Gaussian template and rescale it to account for the different CTA instrumental and observational configurations. Simulations are performed for different configurations of CTA and for the ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) mini-array. The northern CTA configuration will provide an improvement of a factor of ˜3 in accuracy with an observing time comparable to that of MAGIC (73 h). Unless the VHE spectrum above 1 TeV behaves differently from what we presently know, unreasonably long observing times are required for a significant detection of the pulsations of the Crab pulsar with the high-energy-range sub-arrays. We also found that an independent VHE timing analysis is feasible with Large Size Telescopes. CTA will provide a significant improvement in determining the VHE pulse shape parameters necessary to constrain theoretical models of the gamma-ray emission of the Crab pulsar. One of such parameters is the shift in phase between peaks in the pulse profile at VHE and in other energy bands that, if detected, may point to different locations of the emission regions.

Performance Issues Related to Web Service Usage for Remote Data Access

International Nuclear Information System (INIS)

Pais, V. F.; Stancalie, V.; Mihailescu, F. A.; Totolici, M. C.

2008-01-01

Web services are starting to be widely used in applications for remotely accessing data. This is of special interest for research based on small and medium scale fusion devices, since scientists participating remotely to experiments are accessing large amounts of data over the Internet. Recent tests were conducted to see how the new network traffic, generated by the use of web services, can be integrated in the existing infrastructure and what would be the impact over existing applications, especially those used in a remote participation scenario

Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

Energy Technology Data Exchange (ETDEWEB)

Ninh, Giang Nguyen; Phongphaeth, Pengvanich, E-mail: phongphaeth.p@chula.ac.th; Nares, Chankow [Nuclear Engineering Department, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330 (Thailand); Hao, Quang Nguyen [Vietnam Atomic Energy Institute, Ministry of Science and Technology, Hanoi (Viet Nam)

2016-01-22

Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.

Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

International Nuclear Information System (INIS)

Ninh, Giang Nguyen; Phongphaeth, Pengvanich; Nares, Chankow; Hao, Quang Nguyen

2016-01-01

Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method

gemcWeb: A Cloud Based Nuclear Physics Simulation Software

Science.gov (United States)

Markelon, Sam

2017-09-01

gemcWeb allows users to run nuclear physics simulations from the web. Being completely device agnostic, scientists can run simulations from anywhere with an Internet connection. Having a full user system, gemcWeb allows users to revisit and revise their projects, and share configurations and results with collaborators. gemcWeb is based on simulation software gemc, which is based on standard GEant4. gemcWeb requires no C++, gemc, or GEant4 knowledge. Using a simple but powerful GUI allows users to configure their project from geometries and configurations stored on the deployment server. Simulations are then run on the server, with results being posted to the user, and then securely stored. Python based and open-source, the main version of gemcWeb is hosted internally at Jefferson National Labratory and used by the CLAS12 and Electron-Ion Collider Project groups. However, as the software is open-source, and hosted as a GitHub repository, an instance can be deployed on the open web, or any institution's intra-net. An instance can be configured to host experiments specific to an institution, and the code base can be modified by any individual or group. Special thanks to: Maurizio Ungaro, PhD., creator of gemc; Markus Diefenthaler, PhD., advisor; and Kyungseon Joo, PhD., advisor.

Texting and accessing the web while driving: traffic citations and crashes among young adult drivers.

Science.gov (United States)

Cook, Jerry L; Jones, Randall M

2011-12-01

We examined relations between young adult texting and accessing the web while driving with driving outcomes (viz. crashes and traffic citations). Our premise is that engaging in texting and accessing the web while driving is not only distracting but that these activities represent a pattern of behavior that leads to an increase in unwanted outcomes, such as crashes and citations. College students (N = 274) on 3 campuses (one in California and 2 in Utah) completed an electronic questionnaire regarding their driving experience and cell phone use. Our data indicate that 3 out of 4 (74.3%) young adults engage in texting while driving, over half on a weekly basis (51.8%), and some engage in accessing the web while driving (16.8%). Data analysis revealed a relationship between these cell phone behaviors and traffic citations and crashes. The findings support Jessor and Jessor's (1977) "problem behavior syndrome" by showing that traffic citations are related to texting and accessing the web while driving and that crashes are related to accessing the web while driving. Limitations and recommendations are discussed.

Monte Carlo simulation for dual head gamma camera

International Nuclear Information System (INIS)

Osman, Yousif Bashir Soliman

2015-12-01

Monte Carlo (MC) simulation technique was used widely in medical physics applications. In nuclear medicine MC was used to design new medical imaging devices such as positron emission tomography (PET), gamma camera and single photon emission computed tomography (SPECT). Also it can be used to study the factors affecting image quality and internal dosimetry, Gate is on of monte Carlo code that has a number of advantages for simulation of SPECT and PET. There is a limit accessibilities in machines which are used in clinics because of the work load of machines. This makes it hard to evaluate some factors effecting machine performance which must be evaluated routinely. Also because of difficulties of carrying out scientific research and training of students, MC model can be optimum solution for the problem. The aim of this study was to use gate monte Carlo code to model Nucline spirit, medico dual head gamma camera hosted in radiation and isotopes center of Khartoum which is equipped with low energy general purpose LEGP collimators. This was used model to evaluate spatial resolution and sensitivity which is important factor affecting image quality and to demonstrate the validity of gate by comparing experimental results with simulation results on spatial resolution. The gate model of Nuclide spirit, medico dual head gamma camera was developed by applying manufacturer specifications. Then simulation was run. In evaluation of spatial resolution the FWHM was calculated from image profile of line source of Tc 99m gammas emitter of energy 140 KeV at different distances from modeled camera head at 5,10,15,20,22,27,32,37 cm and for these distances the spatial resolution was founded to be 5.76, 7.73, 10.7, 13.8, 14.01,16.91, 19.75 and 21.9 mm, respectively. These results showed a decrement of spatial resolution with increase of the distance between object (line source) and collimator in linear manner. FWHM calculated at 10 cm was compared with experimental results. The

A Comparison Of GADRAS Simulated And Measured Gamma Ray Spectra

International Nuclear Information System (INIS)

Jeffcoat, R.; Salaymeh, S.

2010-01-01

Gamma-ray radiation detection systems are continuously being developed and improved for detecting the presence of radioactive material and for identifying isotopes present. Gamma-ray spectra, from many different isotopes and in different types and thicknesses of attenuation material and matrixes, are needed to evaluate the performance of these devices. Recently, a test and evaluation exercise was performed by the Savannah River National Laboratory that required a large number of gamma-ray spectra. Simulated spectra were used for a major portion of the testing in order to provide a pool of data large enough for the results to be statistically significant. The test data set was comprised of two types of data, measured and simulated. The measured data were acquired with a hand-held Radioisotope Identification Device (RIID) and simulated spectra were created using Gamma Detector Response and Analysis Software (GADRAS, Mitchell and Mattingly, Sandia National Laboratory). GADRAS uses a one-dimensional discrete ordinate calculation to simulate gamma-ray spectra. The measured and simulated spectra have been analyzed and compared. This paper will discuss the results of the comparison and offer explanations for spectral differences.

Prototype of an expert system to help nuclide identification in gamma spectrum analysis

International Nuclear Information System (INIS)

Jayanthi, Kasi Annapurna; Corcuera, Raquel Paviotti; Oliveira, Gina Maira B.

1995-01-01

This report describes the development and use of IDENT, prototype of an expert system that helps the researcher to identify radionuclides in gamma-ray spectroscopy. Normally the method adopted by the researcher is iterative, time consuming and becomes complicated in the analysis of large and complex gamma-ray spectra. The present expert system is based on the knowledge transmitted by expert and specialists in this area and the results show that it is helpful for researches who perform nuclide identification through gamma-ray spectroscopy. The gamma-ray spectrum of a material sample with about 140 peaks would take about a week or two be analysed by a specialist. The same task can be done in a few minutes using this expert system. (author). 14 refs., 2 figs

A physical implementation of the Turing machine accessed through Web

Directory of Open Access Journals (Sweden)

Marijo Maracic

2008-11-01

Full Text Available A Turing machine has an important role in education in the field of computer science, as it is a milestone in courses related to automata theory, theory of computation and computer architecture. Its value is also recognized in the Computing Curricula proposed by the Association for Computing Machinery (ACM and IEEE Computer Society. In this paper we present a physical implementation of the Turing machine accessed through Web. To enable remote access to the Turing machine, an implementation of the client-server architecture is built. The web interface is described in detail and illustrations of remote programming, initialization and the computation of the Turing machine are given. Advantages of such approach and expected benefits obtained by using remotely accessible physical implementation of the Turing machine as an educational tool in the teaching process are discussed.

Gamma-gamma density and lithology tools simulation based on GEANT4 advanced low energy Compton scattering (GALECS) package

International Nuclear Information System (INIS)

Esmaeili-sani, Vahid; Moussavi-zarandi, Ali; Boghrati, Behzad; Afarideh, Hossein

2012-01-01

Geophysical bore-hole data represent the physical properties of rocks, such as density and formation lithology, as a function of depth in a well. Properties of rocks are obtained from gamma ray transport logs. Transport of gamma rays, from a 137 Cs point gamma source situated in a bore-hole tool, through rock media to detectors, has been simulated using a GEANT4 radiation transport code. The advanced Compton scattering concepts were used to gain better analyses about well formation. The simulation and understanding of advanced Compton scattering highly depends on how accurately the effects of Doppler broadening and Rayleigh scattering are taken into account. A Monte Carlo package that simulates the gamma-gamma well logging tools based on GEANT4 advanced low energy Compton scattering (GALECS).

Calibration and simulation of a gamma array for DRAGON at ISAC

CERN Document Server

Gigliotti, D G; Hussein, A H

2003-01-01

A gamma ray detector has been built for the DRAGON facility at TRIUMF to detect the gamma ray emitted in astrophysically important proton and alpha radiative capture reactions. The gamma detector was designed to balance cost with maximum solid angle coverage and efficiency. To study the properties of the current design, GEANT simulations are being carried out and compared with prototype measurements using calibration sources and radioactive beams supplied by ISAC. Simulations will be compared with data allowing a realistic simulation to be produced. This modified simulation will then be used to provide efficiency predictions of the gamma array when an actual experiment's parameters are inputted. Using the simulated efficiency of the array, cross sections for radiative capture can be calculated from the measured gamma ray yields, for the individual reactions. The following will outline some initial results of background suppression of beam related experiments. Also shown, are some preliminary comparison of poi...

3PAC: Enforcing Access Policies for Web Services

NARCIS (Netherlands)

van Bemmel, J.; Wegdam, M.; Lagerberg, K.

Web Services fail to deliver on the promise of ubiquitous deployment and seamless interoperability due to the lack of a uniform, standards-based approach to all aspects of security. In particular, the enforcement of access policies in a Service Oriented Architecture is not addressed adequately. We

Fermi LAT Search for Dark Matter in Gamma-Ray Lines and the Inclusive Photon Spectrum

Science.gov (United States)

Ackermann, M.; Ajello, M.; Albert, A.; Baldini, L.; Barbiellini, G.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.;

ARCAS (ACACIA Regional Climate-data Access System) -- a Web Access System for Climate Model Data Access, Visualization and Comparison

Science.gov (United States)

Hakkarinen, C.; Brown, D.; Callahan, J.; hankin, S.; de Koningh, M.; Middleton-Link, D.; Wigley, T.

2001-05-01

A Web-based access system to climate model output data sets for intercomparison and analysis has been produced, using the NOAA-PMEL developed Live Access Server software as host server and Ferret as the data serving and visualization engine. Called ARCAS ("ACACIA Regional Climate-data Access System"), and publicly accessible at http://dataserver.ucar.edu/arcas, the site currently serves climate model outputs from runs of the NCAR Climate System Model for the 21st century, for Business as Usual and Stabilization of Greenhouse Gas Emission scenarios. Users can select, download, and graphically display single variables or comparisons of two variables from either or both of the CSM model runs, averaged for monthly, seasonal, or annual time resolutions. The time length of the averaging period, and the geographical domain for download and display, are fully selectable by the user. A variety of arithmetic operations on the data variables can be computed "on-the-fly", as defined by the user. Expansions of the user-selectable options for defining analysis options, and for accessing other DOD-compatible ("Distributed Ocean Data System-compatible") data sets, residing at locations other than the NCAR hardware server on which ARCAS operates, are planned for this year. These expansions are designed to allow users quick and easy-to-operate web-based access to the largest possible selection of climate model output data sets available throughout the world.

Improving Inpatient Surveys: Web-Based Computer Adaptive Testing Accessed via Mobile Phone QR Codes.

Science.gov (United States)

Chien, Tsair-Wei; Lin, Weir-Sen

2016-03-02

The National Health Service (NHS) 70-item inpatient questionnaire surveys inpatients on their perceptions of their hospitalization experience. However, it imposes more burden on the patient than other similar surveys. The literature shows that computerized adaptive testing (CAT) based on item response theory can help shorten the item length of a questionnaire without compromising its precision. Our aim was to investigate whether CAT can be (1) efficient with item reduction and (2) used with quick response (QR) codes scanned by mobile phones. After downloading the 2008 inpatient survey data from the Picker Institute Europe website and analyzing the difficulties of this 70-item questionnaire, we used an author-made Excel program using the Rasch partial credit model to simulate 1000 patients' true scores followed by a standard normal distribution. The CAT was compared to two other scenarios of answering all items (AAI) and the randomized selection method (RSM), as we investigated item length (efficiency) and measurement accuracy. The author-made Web-based CAT program for gathering patient feedback was effectively accessed from mobile phones by scanning the QR code. We found that the CAT can be more efficient for patients answering questions (ie, fewer items to respond to) than either AAI or RSM without compromising its measurement accuracy. A Web-based CAT inpatient survey accessed by scanning a QR code on a mobile phone was viable for gathering inpatient satisfaction responses. With advances in technology, patients can now be offered alternatives for providing feedback about hospitalization satisfaction. This Web-based CAT is a possible option in health care settings for reducing the number of survey items, as well as offering an innovative QR code access.

Frequency and spectrum of mutations induced by gamma irradiation in single, double and triple dwarf wheats

International Nuclear Information System (INIS)

Dhonukshe, B.L.

1981-01-01

Induced mutation studies were carried with three dwarf wheat varieties viz., ''Sonalika'', ''Chhoti Lerma'' and ''Hira'', considered to be single, double and trible dwarfs, respectively. Gamma-rays were used as a source of irradiation. Frequency of chlorophyll mutations were comparatively low and the spectrum was narrow. Chlorophyll mutations were altogether absent in the variety ''Sonalika''. A very wide spectrum of viable mutations affecting stem, leaf, ear growth habit, maturity and fertility characteristics was observed in the M 2 . The cumulative frequency of all the mutants together was quite high, which varied with the varieties. There were varietal differences in the composition and width of the spectrum induced by gamma-rays. The dwarf mutants having desirable leaf and spike characters were isolated in all the three varieties. (author)

Gamma-gamma density and lithology tools simulation based on GEANT4 advanced low energy Compton scattering (GALECS) package

Energy Technology Data Exchange (ETDEWEB)

Esmaeili-sani, Vahid, E-mail: vaheed_esmaeely80@yahoo.com [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of); Moussavi-zarandi, Ali; Boghrati, Behzad; Afarideh, Hossein [Department of Nuclear Engineering and Physics, Amirkabir University of Technology, P.O. Box 4155-4494, Tehran (Iran, Islamic Republic of)

2012-02-01

Geophysical bore-hole data represent the physical properties of rocks, such as density and formation lithology, as a function of depth in a well. Properties of rocks are obtained from gamma ray transport logs. Transport of gamma rays, from a {sup 137}Cs point gamma source situated in a bore-hole tool, through rock media to detectors, has been simulated using a GEANT4 radiation transport code. The advanced Compton scattering concepts were used to gain better analyses about well formation. The simulation and understanding of advanced Compton scattering highly depends on how accurately the effects of Doppler broadening and Rayleigh scattering are taken into account. A Monte Carlo package that simulates the gamma-gamma well logging tools based on GEANT4 advanced low energy Compton scattering (GALECS).

MONTE CARLO RADIATION TRANSFER SIMULATIONS OF PHOTOSPHERIC EMISSION IN LONG-DURATION GAMMA-RAY BURSTS

Energy Technology Data Exchange (ETDEWEB)

Lazzati, Davide [Department of Physics, Oregon State University, 301 Weniger Hall, Corvallis, OR 97331 (United States)

2016-10-01

We present MCRaT, a Monte Carlo Radiation Transfer code for self-consistently computing the light curves and spectra of the photospheric emission from relativistic, unmagnetized jets. We apply MCRaT to a relativistic hydrodynamic simulation of a long-duration gamma-ray burst jet, and present the resulting light curves and time-dependent spectra for observers at various angles from the jet axis. We compare our results to observational results and find that photospheric emission is a viable model to explain the prompt phase of long-duration gamma-ray bursts at the peak frequency and above, but faces challenges when reproducing the flat spectrum below the peak frequency. We finally discuss possible limitations of these results both in terms of the hydrodynamics and the radiation transfer and how these limitations could affect the conclusions that we present.

Facilitating access to the web of data a guide for librarians

CERN Document Server

Stuart, David

2011-01-01

Offers an introduction to the web of data and the semantic web, exploring technologies including APIs, microformats and linked data. This title includes topical commentary and practical examples that explore how information professionals can harness the power of this phenomenon to inform strategy and become facilitators of access to data.

A Dynamic Defense Modeling and Simulation Methodology using Semantic Web Services

Directory of Open Access Journals (Sweden)

Kangsun Lee

2010-04-01

Full Text Available Defense Modeling and Simulations require interoperable and autonomous federates in order to fully simulate complex behavior of war-fighters and to dynamically adapt themselves to various war-game events, commands and controls. In this paper, we propose a semantic web service based methodology to develop war-game simulations. Our methodology encapsulates war-game logic into a set of web services with additional semantic information in WSDL (Web Service Description Language and OWL (Web Ontology Language. By utilizing dynamic discovery and binding power of semantic web services, we are able to dynamically reconfigure federates according to various simulation events. An ASuW (Anti-Surface Warfare simulator is constructed to demonstrate the methodology and successfully shows that the level of interoperability and autonomy can be greatly improved.

Performance simulation and structure design of Binode CdZnTe gamma-ray detector

International Nuclear Information System (INIS)

Niu Libo; Li Yulan; Fu Jianqiang; Jiang Hao; Zhang Lan; He Bin; Li Yuanjing

2014-01-01

A new electrode structure CdZnTe (Cadmium Zinc Telluride) detector named Binode CdZnTe has been pro- posed in this paper. Together with the softwares of MAXWELL, GEANT4, and ROOT, the charge collection process and its gamma spectrum of the detector have been simulated and the detector structure has been optimized. In order to improve its performance further, Compton scattering effect correction has been used. The simulation results demonstrate that with refined design and Compton scattering effect correction, Binode CdZnTe detectors is capable of achieving 3.92% FWHM at 122 keV, and 1.27% FWHM at 662 keV. Com- pared with other single-polarity (electron-only) detector configurations, Binode CdZnTe detector offers a cost effective and simple structure alternative with comparable energy resolution. (authors)

Simulating Gamma-Ray Emission in Star-forming Galaxies

Energy Technology Data Exchange (ETDEWEB)

Pfrommer, Christoph [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Pakmor, Rüdiger; Simpson, Christine M.; Springel, Volker, E-mail: cpfrommer@aip.de [Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)

2017-10-01

Star-forming galaxies emit GeV and TeV gamma-rays that are thought to originate from hadronic interactions of cosmic-ray (CR) nuclei with the interstellar medium. To understand the emission, we have used the moving-mesh code Arepo to perform magnetohydrodynamical galaxy formation simulations with self-consistent CR physics. Our galaxy models exhibit a first burst of star formation that injects CRs at supernovae. Once CRs have sufficiently accumulated in our Milky Way–like galaxy, their buoyancy force overcomes the magnetic tension of the toroidal disk field. As field lines open up, they enable anisotropically diffusing CRs to escape into the halo and to accelerate a bubble-like, CR-dominated outflow. However, these bubbles are invisible in our simulated gamma-ray maps of hadronic pion-decay and secondary inverse-Compton emission because of low gas density in the outflows. By adopting a phenomenological relation between star formation rate (SFR) and far-infrared emission and assuming that gamma-rays mainly originate from decaying pions, our simulated galaxies can reproduce the observed tight relation between far-infrared and gamma-ray emission, independent of whether we account for anisotropic CR diffusion. This demonstrates that uncertainties in modeling active CR transport processes only play a minor role in predicting gamma-ray emission from galaxies. We find that in starbursts, most of the CR energy is “calorimetrically” lost to hadronic interactions. In contrast, the gamma-ray emission deviates from this calorimetric property at low SFRs due to adiabatic losses, which cannot be identified in traditional one-zone models.

Simulating Gamma-Ray Emission in Star-forming Galaxies

Science.gov (United States)

Pfrommer, Christoph; Pakmor, Rüdiger; Simpson, Christine M.; Springel, Volker

2017-10-01

Star-forming galaxies emit GeV and TeV gamma-rays that are thought to originate from hadronic interactions of cosmic-ray (CR) nuclei with the interstellar medium. To understand the emission, we have used the moving-mesh code Arepo to perform magnetohydrodynamical galaxy formation simulations with self-consistent CR physics. Our galaxy models exhibit a first burst of star formation that injects CRs at supernovae. Once CRs have sufficiently accumulated in our Milky Way-like galaxy, their buoyancy force overcomes the magnetic tension of the toroidal disk field. As field lines open up, they enable anisotropically diffusing CRs to escape into the halo and to accelerate a bubble-like, CR-dominated outflow. However, these bubbles are invisible in our simulated gamma-ray maps of hadronic pion-decay and secondary inverse-Compton emission because of low gas density in the outflows. By adopting a phenomenological relation between star formation rate (SFR) and far-infrared emission and assuming that gamma-rays mainly originate from decaying pions, our simulated galaxies can reproduce the observed tight relation between far-infrared and gamma-ray emission, independent of whether we account for anisotropic CR diffusion. This demonstrates that uncertainties in modeling active CR transport processes only play a minor role in predicting gamma-ray emission from galaxies. We find that in starbursts, most of the CR energy is “calorimetrically” lost to hadronic interactions. In contrast, the gamma-ray emission deviates from this calorimetric property at low SFRs due to adiabatic losses, which cannot be identified in traditional one-zone models.

PERFORMANCE OF OPPORTUNISTIC SPECTRUM ACCESS WITH SENSING ERROR IN COGNITIVE RADIO AD HOC NETWORKS

Directory of Open Access Journals (Sweden)

N. ARMI

2012-04-01

Full Text Available Sensing in opportunistic spectrum access (OSA has a responsibility to detect the available channel by performing binary hypothesis as busy or idle states. If channel is busy, secondary user (SU cannot access and refrain from data transmission. SU is allowed to access when primary user (PU does not use it (idle states. However, channel is sensed on imperfect communication link. Fading, noise and any obstacles existed can cause sensing errors in PU signal detection. False alarm detects idle states as a busy channel while miss-identification detects busy states as an idle channel. False detection makes SU refrain from transmission and reduces number of bits transmitted. On the other hand, miss-identification causes SU collide to PU transmission. This paper study the performance of OSA based on the greedy approach with sensing errors by the restriction of maximum collision probability allowed (collision threshold by PU network. The throughput of SU and spectrum capacity metric is used to evaluate OSA performance and make comparisons to those ones without sensing error as function of number of slot based on the greedy approach. The relations between throughput and signal to noise ratio (SNR with different collision probability as well as false detection with different SNR are presented. According to the obtained results show that CR users can gain the reward from the previous slot for both of with and without sensing errors. It is indicated by the throughput improvement as slot number increases. However, sensing on imperfect channel with sensing errors can degrade the throughput performance. Subsequently, the throughput of SU and spectrum capacity improves by increasing maximum collision probability allowed by PU network as well. Due to frequent collision with PU, the throughput of SU and spectrum capacity decreases at certain value of collision threshold. Computer simulation is used to evaluate and validate these works.

Access Control of Web and Java Based Applications

Science.gov (United States)

Tso, Kam S.; Pajevski, Michael J.; Johnson, Bryan

2011-01-01

Cyber security has gained national and international attention as a result of near continuous headlines from financial institutions, retail stores, government offices and universities reporting compromised systems and stolen data. Concerns continue to rise as threats of service interruption, and spreading of viruses become ever more prevalent and serious. Controlling access to application layer resources is a critical component in a layered security solution that includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. In this paper we discuss the development of an application-level access control solution, based on an open-source access manager augmented with custom software components, to provide protection to both Web-based and Java-based client and server applications.

GROSS- GAMMA RAY OBSERVATORY ATTITUDE DYNAMICS SIMULATOR

Science.gov (United States)

Garrick, J.

1994-01-01

The Gamma Ray Observatory (GRO) spacecraft will constitute a major advance in gamma ray astronomy by offering the first opportunity for comprehensive observations in the range of 0.1 to 30,000 megaelectronvolts (MeV). The Gamma Ray Observatory Attitude Dynamics Simulator, GROSS, is designed to simulate this mission. The GRO Dynamics Simulator consists of three separate programs: the Standalone Profile Program; the Simulator Program, which contains the Simulation Control Input/Output (SCIO) Subsystem, the Truth Model (TM) Subsystem, and the Onboard Computer (OBC) Subsystem; and the Postprocessor Program. The Standalone Profile Program models the environment of the spacecraft and generates a profile data set for use by the simulator. This data set contains items such as individual external torques; GRO spacecraft, Tracking and Data Relay Satellite (TDRS), and solar and lunar ephemerides; and star data. The Standalone Profile Program is run before a simulation. The SCIO subsystem is the executive driver for the simulator. It accepts user input, initializes parameters, controls simulation, and generates output data files and simulation status display. The TM subsystem models the spacecraft dynamics, sensors, and actuators. It accepts ephemerides, star data, and environmental torques from the Standalone Profile Program. With these and actuator commands from the OBC subsystem, the TM subsystem propagates the current state of the spacecraft and generates sensor data for use by the OBC and SCIO subsystems. The OBC subsystem uses sensor data from the TM subsystem, a Kalman filter (for attitude determination), and control laws to compute actuator commands to the TM subsystem. The OBC subsystem also provides output data to the SCIO subsystem for output to the analysts. The Postprocessor Program is run after simulation is completed. It generates printer and CRT plots and tabular reports of the simulated data at the direction of the user. GROSS is written in FORTRAN 77 and

Web-Based Distributed Simulation of Aeronautical Propulsion System

Science.gov (United States)

Zheng, Desheng; Follen, Gregory J.; Pavlik, William R.; Kim, Chan M.; Liu, Xianyou; Blaser, Tammy M.; Lopez, Isaac

2001-01-01

An application was developed to allow users to run and view the Numerical Propulsion System Simulation (NPSS) engine simulations from web browsers. Simulations were performed on multiple INFORMATION POWER GRID (IPG) test beds. The Common Object Request Broker Architecture (CORBA) was used for brokering data exchange among machines and IPG/Globus for job scheduling and remote process invocation. Web server scripting was performed by JavaServer Pages (JSP). This application has proven to be an effective and efficient way to couple heterogeneous distributed components.

Simple Enough--Even for Web Virgins: Lisa Mitten's Access to Native American Web Sites. Web Site Review Essay.

Science.gov (United States)

Belgarde, Mary Jiron

1998-01-01

A mixed-blood Mohawk urban Indian and university librarian, Lisa Mitten provides access to Web sites with solid information about American Indians. Links are provided to 10 categories--Native nations, Native organizations, Indian education, Native media, powwows and festivals, Indian music, Native arts, Native businesses, and Indian-oriented home…

Cloud-based Web Services for Near-Real-Time Web access to NPP Satellite Imagery and other Data

Science.gov (United States)

Evans, J. D.; Valente, E. G.

2010-12-01

We are building a scalable, cloud computing-based infrastructure for Web access to near-real-time data products synthesized from the U.S. National Polar-Orbiting Environmental Satellite System (NPOESS) Preparatory Project (NPP) and other geospatial and meteorological data. Given recent and ongoing changes in the the NPP and NPOESS programs (now Joint Polar Satellite System), the need for timely delivery of NPP data is urgent. We propose an alternative to a traditional, centralized ground segment, using distributed Direct Broadcast facilities linked to industry-standard Web services by a streamlined processing chain running in a scalable cloud computing environment. Our processing chain, currently implemented on Amazon.com's Elastic Compute Cloud (EC2), retrieves raw data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) and synthesizes data products such as Sea-Surface Temperature, Vegetation Indices, etc. The cloud computing approach lets us grow and shrink computing resources to meet large and rapid fluctuations (twice daily) in both end-user demand and data availability from polar-orbiting sensors. Early prototypes have delivered various data products to end-users with latencies between 6 and 32 minutes. We have begun to replicate machine instances in the cloud, so as to reduce latency and maintain near-real time data access regardless of increased data input rates or user demand -- all at quite moderate monthly costs. Our service-based approach (in which users invoke software processes on a Web-accessible server) facilitates access into datasets of arbitrary size and resolution, and allows users to request and receive tailored and composite (e.g., false-color multiband) products on demand. To facilitate broad impact and adoption of our technology, we have emphasized open, industry-standard software interfaces and open source software. Through our work, we envision the widespread establishment of similar, derived, or interoperable systems for

Gamma spectrum measurement in a swimming-pool-type reactor; Mesure du spectre {gamma} d'une pile piscine

Energy Technology Data Exchange (ETDEWEB)

Pla, E [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1969-07-01

After recalling the various modes of interaction of gamma rays with matter, the authors describe the design of a spectrometer for gamma energies of between 0.3 and 10 MeV. This spectrometer makes use of the Compton and pair-production effects without eliminating them. The collimator, the crystals and the electronics have been studied in detail and are described in their final form. The problem of calibrating the apparatus is then considered ; numerous graphs are given. The sensitivity of the spectrometer for different energies is determined mainly for the 'Compton effect' group. Finally, in the last part of the report, are given results of an experimental measurement of the gamma spectrum of a swimming-pool type reactor with new elements. (author) [French] Apres un rappel des differents modes d'interaction des rayons gamma avec la matiere, nous decrivons la conception d'un spectrometre pour les energies gamma s'etendant de 0,3 a 10 MeV. Ce spectrometre utilise les effets Compton et creation de paires sans les eliminer. Le collimateur, les cristaux et l'electronique sont entierement etudies et decrits dans leur realisation definitive. Ensuite, le probleme de l'etalonnage de l'appareil est envisage; de nombreuses courbes sont donnees. La sensibilite du spectrometre pour les differentes energies est determinee principalement pour le groupe ''effet Compton''. Enfin, les resultats d'une experience de mesure du spectre gamma d'une pile piscine avec elements neufs sont donnes dans la derniere partie. (auteur)

Calculation of the energy spectrum of atmospheric gamma-rays between 1 and 1000 MeV

International Nuclear Information System (INIS)

Martin, I.M.; Dutra, S.L.G.; Palmeira, R.A.R.

The energy spectrum of atmospheric gamma-rays at 4 g/cm 2 has been calculated for cut-off rigidities of 4.5, 10 and 16 GV. The considered processes for the production of these gamma-rays were the π 0 decay plus the bremsstrahlung from primary, secondary like splash and re-entrant albedo electrons. The calculations indicated that the spectrum could be fitted to a power law in energy, with the exponential index varying from 1.1 in the energy range 1 - 10 MeV, to 1.4 in the energy range 10 - 200 MeV and 1.8 in the energy range 200 - 1000 MeV. These results are discussed [pt

Monte Carlo simulations of prompt-gamma emission during carbon ion irradiation

Energy Technology Data Exchange (ETDEWEB)

Le Foulher, F.; Bajard, M.; Chevallier, M.; Dauvergne, D.; Henriquet, P.; Ray, C.; Testa, E.; Testa, M. [Universite de Lyon 1, F-69003 Lyon (France); IN2P3/CNRS, UMR 5822, Institut de Physique Nucleaire de Lyon, F-69622 Villeurbanne (France); Freud, N.; Letang, J. M. [Laboratoire de Controles Non Destructifs Par Rayonnements Ionisants, INSA-Lyon, F-69621 Villeurbanne cedex (France); Karkar, S. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Plescak, R.; Schardt, D. [Gesellschaft fur Schwerionenforschung (GSI), D-64291 Darmstadt (Germany)

2009-07-01

Monte Carlo simulations based on the Geant4 tool-kit (version 9.1) were performed to study the emission of secondary prompt gamma-rays produced by nuclear reactions during carbon ion-beam therapy. These simulations were performed along with an experimental program and instrumentation developments which aim at designing a prompt gamma-ray device for real-time control of hadron therapy. The objective of the present study is twofold: first, to present the features of the prompt gamma radiation in the case of carbon ion irradiation; secondly, to simulate the experimental setup and to compare measured and simulated counting rates corresponding to various experiments. For each experiment, we found that simulations overestimate prompt gamma-ray detection yields by a factor of 12. Uncertainties in fragmentation cross sections and binary cascade model cannot explain such discrepancies. The so-called 'photon evaporation' model is therefore questionable and its modification is currently in progress. (authors)

New data access with HTTP/WebDAV in the ATLAS experiment

CERN Document Server

Elmsheuser, Johannes; The ATLAS collaboration; Serfon, Cedric; Garonne, Vincent; Blunier, Sylvain; Lavorini, Vincenzo; Nilsson, Paul

2015-01-01

With the exponential growth of LHC (Large Hadron Collider) data in the years 2010-2012, distributed computing has become the established way to analyze collider data. The ATLAS experiment Grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centres to smaller university clusters. So far the storage technologies and access protocols to the clusters that host this tremendous amount of data vary from site to site. HTTP/WebDAV offers the possibility to use a unified industry standard to access the storage. We present the deployment and testing of HTTP/WebDAV for local and remote data access in the ATLAS experiment for the new data management system Rucio and the PanDA workload management system. Deployment and large scale tests have been performed using the Grid testing system HammerCloud and the ROOT HTTP plugin Davix.

New data access with HTTP/WebDAV in the ATLAS experiment

CERN Document Server

Elmsheuser, Johannes; The ATLAS collaboration; Serfon, Cedric; Garonne, Vincent; Blunier, Sylvain; Lavorini, Vincenzo; Nilsson, Paul

2015-01-01

With the exponential growth of LHC (Large Hadron Collider) data in the years 2010-2012, distributed computing has become the established way to analyse collider data. The ATLAS experiment Grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centres to smaller university clusters. So far the storage technologies and access protocols to the clusters that host this tremendous amount of data vary from site to site. HTTP/WebDAV offers the possibility to use a unified industry standard to access the storage. We present the deployment and testing of HTTP/WebDAV for local and remote data access in the ATLAS experiment for the new data management system Rucio and the PanDA workload management system. Deployment and large scale tests have been performed using the Grid testing system HammerCloud and the ROOT HTTP plugin Davix.

Accessibility and content of individualized adult reconstructive hip and knee/musculoskeletal oncology fellowship web sites

Directory of Open Access Journals (Sweden)

Bradley L. Young, MD

2018-06-01

Conclusions: Several programs participating in the combined Adult Reconstructive Hip and Knee/Musculoskeletal Oncology Fellowship Match did not have accessible web sites. Of the web sites that were accessible, none contained comprehensive information and the majority lacked information that has been previously identified as being important to perspective applicants.

Applications of Monte Carlo simulations of gamma-ray spectra

International Nuclear Information System (INIS)

Clark, D.D.

1995-01-01

A short, convenient computer program based on the Monte Carlo method that was developed to generate simulated gamma-ray spectra has been found to have useful applications in research and teaching. In research, we use it to predict spectra in neutron activation analysis (NAA), particularly in prompt gamma-ray NAA (PGNAA). In teaching, it is used to illustrate the dependence of detector response functions on the nature of gamma-ray interactions, the incident gamma-ray energy, and detector geometry

Implementing Recommendations From Web Accessibility Guidelines: A Comparative Study of Nondisabled Users and Users With Visual Impairments.

Science.gov (United States)

Schmutz, Sven; Sonderegger, Andreas; Sauer, Juergen

2017-09-01

The present study examined whether implementing recommendations of Web accessibility guidelines would have different effects on nondisabled users than on users with visual impairments. The predominant approach for making Web sites accessible for users with disabilities is to apply accessibility guidelines. However, it has been hardly examined whether this approach has side effects for nondisabled users. A comparison of the effects on both user groups would contribute to a better understanding of possible advantages and drawbacks of applying accessibility guidelines. Participants from two matched samples, comprising 55 participants with visual impairments and 55 without impairments, took part in a synchronous remote testing of a Web site. Each participant was randomly assigned to one of three Web sites, which differed in the level of accessibility (very low, low, and high) according to recommendations of the well-established Web Content Accessibility Guidelines 2.0 (WCAG 2.0). Performance (i.e., task completion rate and task completion time) and a range of subjective variables (i.e., perceived usability, positive affect, negative affect, perceived aesthetics, perceived workload, and user experience) were measured. Higher conformance to Web accessibility guidelines resulted in increased performance and more positive user ratings (e.g., perceived usability or aesthetics) for both user groups. There was no interaction between user group and accessibility level. Higher conformance to WCAG 2.0 may result in benefits for nondisabled users and users with visual impairments alike. Practitioners may use the present findings as a basis for deciding on whether and how to implement accessibility best.

Security Guidelines for the Development of Accessible Web Applications through the implementation of intelligent systems

Directory of Open Access Journals (Sweden)

Luis Joyanes Aguilar

2009-12-01

Full Text Available Due to the significant increase in threats, attacks and vulnerabilities that affect the Web in recent years has resulted the development and implementation of pools and methods to ensure security measures in the privacy, confidentiality and data integrity of users and businesses. Under certain circumstances, despite the implementation of these tools do not always get the flow of information which is passed in a secure manner. Many of these security tools and methods cannot be accessed by people who have disabilities or assistive technologies which enable people to access the Web efficiently. Among these security tools that are not accessible are the virtual keyboard, the CAPTCHA and other technologies that help to some extent to ensure safety on the Internet and are used in certain measures to combat malicious code and attacks that have been increased in recent times on the Web. Through the implementation of intelligent systems can detect, recover and receive information on the characteristics and properties of the different tools and hardware devices or software with which the user is accessing a web application and through analysis and interpretation of these intelligent systems can infer and automatically adjust the characteristics necessary to have these tools to be accessible by anyone regardless of disability or navigation context. This paper defines a set of guidelines and specific features that should have the security tools and methods to ensure the Web accessibility through the implementation of intelligent systems.

Gamma-ray Background Spectrum and Annihilation Rate in the Baryon-symmetric Big-bang Cosmology

Science.gov (United States)

Puget, J. L.

1973-01-01

An attempt was made to acquire experimental information on the problem of baryon symmetry on a large cosmological scale by observing the annihilation products. Data cover absorption cross sections and background radiation due to other sources for the two main products of annihilation, gamma rays and neutrinos. Test results show that the best direct experimental test for the presence of large scale antimatter lies in the gamma ray background spectrum between 1 and 70 MeV.

Resource allocation in shared spectrum access communications for operators with diverse service requirements

Science.gov (United States)

Kibria, Mirza Golam; Villardi, Gabriel Porto; Ishizu, Kentaro; Kojima, Fumihide; Yano, Hiroyuki

2016-12-01

In this paper, we study inter-operator spectrum sharing and intra-operator resource allocation in shared spectrum access communication systems and propose efficient dynamic solutions to address both inter-operator and intra-operator resource allocation optimization problems. For inter-operator spectrum sharing, we present two competent approaches, namely the subcarrier gain-based sharing and fragmentation-based sharing, which carry out fair and flexible allocation of the available shareable spectrum among the operators subject to certain well-defined sharing rules, traffic demands, and channel propagation characteristics. The subcarrier gain-based spectrum sharing scheme has been found to be more efficient in terms of achieved throughput. However, the fragmentation-based sharing is more attractive in terms of computational complexity. For intra-operator resource allocation, we consider resource allocation problem with users' dissimilar service requirements, where the operator supports users with delay constraint and non-delay constraint service requirements, simultaneously. This optimization problem is a mixed-integer non-linear programming problem and non-convex, which is computationally very expensive, and the complexity grows exponentially with the number of integer variables. We propose less-complex and efficient suboptimal solution based on formulating exact linearization, linear approximation, and convexification techniques for the non-linear and/or non-convex objective functions and constraints. Extensive simulation performance analysis has been carried out that validates the efficiency of the proposed solution.

Gamma spectrum following neutron capture in {sup 167}Er

Energy Technology Data Exchange (ETDEWEB)

Visser, D.; Khoo, T.L.; Lister, C.J. [and others

1995-08-01

Statistical decay from a highly excited state samples all the lower-lying states and, hence, provides a sensitive measure of the level density. Pairing has a major impact on the level density, e.g. creating a pair gap between the 0- and 2-quasiparticle configurations. Hence the shape of the statistical spectrum contains information on pairing, and can be used to provide information on the reduction of pairing with thermal excitation energy. For this reason, we measured the complete spectrum of {gamma}rays following thermal neutron capture in {sup 167}Er. The experiment was performed at the Brookhaven reactor using Compton-suppressed Ge detectors from TESSA. The spectrum, which was corrected for detector response and efficiency, reveals primary (first-step, high-energy) transitions up to nearly 8 MeV, secondary (last-step, lower-energy) transitions, as we as a continuous statistical component. Effort was expanded to identify all lines from contaminant sources and an upper limit of 5% was tentatively set for their contributions. The spectral shape of the statistical spectrum will be compared with theoretical spectra obtained from a calculation of pairing which accounts for a stepwise reduction of the pair correlations as the number of quasiparticles increases. The primary lines which decay directly to the near-yrast states will also be used to deduce the level densities.

Effects of gamma irradiation on the performance of Jatropha (Jatropha curcas L.) accessions

Science.gov (United States)

Surahman, M.; Santosa, E.; Agusta, H.; Aisyah, S. I.; Nisya, F. N.

2018-03-01

This study aimed to assess the effects of mutation by using gamma ray on the performance of jatropha plants. The study was conducted at PAIR BATAN. Jatropha seeds obtained from the collection farm of SBRC LPPM IPB and PT Indocement Tunggal Prakarsa Tbk in Gunung Putri, Bogor, were irradiated. The irradiated seeds were grown in Jonggol Trial Farm of IPB. Gamma irradiation was conducted by using a GCM 4000A device. Treatments consisted of irradiation doses, irradiation methods, and accessions. Irradiation doses given were 175, 200, 225 Gy, and no irradiation (control). Irradiation methods consisted of acute, intermittent, and split-dose. Accessions used in this study were Dompu, Medan, Bima, Lombok, ITP II, IP2P, and Thailand. Results of the study were analysed until 5 months after planting showed that gamma ray mutation gave stimulating and inhibiting effects on similar traits. Irradiation dose of 225 Gy was good to be given in acute, intermittent, and split-dose methods. Irradiation effects were found to be significant in jatropha accessions. Effects of irradiation on production will be published soon.

网络无障碍的发展:政策、理论和方法%Development of Web Accessibility: Policies, Theories and Apporoaches

Institute of Scientific and Technical Information of China (English)

Xiaoming Zeng

2006-01-01

The article is intended to introduce the readers to the concept and background of Web accessibility in the United States. I will first discuss different definitions of Web accessibility. The beneficiaries of accessible Web or the sufferers from inaccessible Web will be discussed based on the type of disability. The importance of Web accessibility will be introduced from the perspectives of ethical, demographic, legal, and financial importance. Web accessibility related standards and legislations will be discussed in great detail. Previous research on evaluating Web accessibility will be presented. Lastly, a system for automated Web accessibility transformation will be introduced as an alternative approach for enhancing Web accessibility.

Thick-foils activation technique for neutron spectrum unfolding with the MINUIT routine-Comparison with GEANT4 simulations

Science.gov (United States)

Vagena, E.; Theodorou, K.; Stoulos, S.

2018-04-01

Neutron activation technique has been applied using a proposed set of twelve thick metal foils (Au, As, Cd, In, Ir, Er, Mn, Ni, Se, Sm, W, Zn) for off-site measurements to obtain the neutron spectrum over a wide energy range (from thermal up to a few MeV) in intense neutron-gamma mixed fields such as around medical Linacs. The unfolding procedure takes into account the activation rates measured using thirteen (n , γ) and two (n , p) reactions without imposing a guess solution-spectrum. The MINUIT minimization routine unfolds a neutron spectrum that is dominated by fast neutrons (70%) peaking at 0.3 MeV, while the thermal peak corresponds to the 15% of the total neutron fluence equal to the epithermal-resonances area. The comparison of the unfolded neutron spectrum against the simulated one with the GEANT4 Monte-Carlo code shows a reasonable agreement within the measurement uncertainties. Therefore, the proposed set of activation thick-foils could be a useful tool in order to determine low flux neutrons spectrum in intense mixed field.

Simulation of COMEDIE Fission Product Plateout Experiment Using GAMMA-FP

International Nuclear Information System (INIS)

Tak, Nam-il; Yoon, Churl

2014-01-01

FThis phenomenon is particularly important under a VHTR design with vented low pressure confinement (VLPC), because the vent allows the prompt release of fission products accumulated within the primary circuit to environment during an initial blow-down phase after pipe break accidents. In order to analyze the fission product plateout, an numerical model was developed by Yoo et al. and incorporated into the GAMMA-FP code in the past. The GAMMA-FP model was validated against two experiment data, i.e., VAMPYR-1 and OGL, during the development phase. One of the well-known experiments for fission product plateout is the COMEDIE experiment. In this work, the COMEDIE experiment has been simulated using the GAMMA-FP code to investigate the reliability and applicability of the plateout model of GAMMA-FP. The COMEDIE experiment for fission product plateout was simulated using the GAMMA-FP code in this work. A good agreement was achieved between the measured and predicted plateout activities. The existing solution scheme was modified to allow larger time step size for fission product analysis in order to speed-up the computational time. Nevertheless, the modification of the existing numerical model of GAMMA-FP is necessary when a simulation capability of a long duration of plateout period (e.g., 60 years) is targeted

MCNPX simulations of the research gamma irradiator at CTEx

International Nuclear Information System (INIS)

Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G.; Silva, Ademir X.

2011-01-01

An accurate knowledge of the dose rate distribution inside an irradiating facility is needed in order to ensure safety and guarantee efficient treatment of materials by exposure to ionizing radiation, since insufficient doses may not produce the desired effects whereas exceeding ones can compromise the properties of the irradiated items. Described in this work, are Monte Carlo simulations of the cavity-type research irradiating facility at Centro Tecnologico do Exercito performed by using the MCNPX radiation transport code. The calculations were intended to provide a better understanding of the measured dose rate distributions produced by a 42-kCi cesium- 137 source, also modeling unmapped regions of interest, either inside or outside the irradiation chambers, such as in experimental channels, or next to the moveable door and across unmapped regions of the chambers, in order to investigate scattering and attenuation of the fluxes and softening of the gamma spectrum and to predict dose rates in case of an accidental opening of the shielded door with the source out of its shielded cask. Results from calculations have been compared to measurements performed with chemical dosimeters. Comparative analyses have consistently shown a very good agreement between calculated and measured relative dose rate distributions and provided an improved knowledge on the gamma ray environment produced by the irradiator. (author)

MCNPX simulations of the research gamma irradiator at CTEx

Energy Technology Data Exchange (ETDEWEB)

Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G., E-mail: tiagorusin@ime.eb.b, E-mail: rebello@ime.eb.b, E-mail: vellozo@cbpf.b, E-mail: renatoguedes@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear; Vital, Helio C., E-mail: vital@ctex.eb.b [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (Brazil); Silva, Ademir X., E-mail: ademir@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear

2011-07-01

An accurate knowledge of the dose rate distribution inside an irradiating facility is needed in order to ensure safety and guarantee efficient treatment of materials by exposure to ionizing radiation, since insufficient doses may not produce the desired effects whereas exceeding ones can compromise the properties of the irradiated items. Described in this work, are Monte Carlo simulations of the cavity-type research irradiating facility at Centro Tecnologico do Exercito performed by using the MCNPX radiation transport code. The calculations were intended to provide a better understanding of the measured dose rate distributions produced by a 42-kCi cesium- 137 source, also modeling unmapped regions of interest, either inside or outside the irradiation chambers, such as in experimental channels, or next to the moveable door and across unmapped regions of the chambers, in order to investigate scattering and attenuation of the fluxes and softening of the gamma spectrum and to predict dose rates in case of an accidental opening of the shielded door with the source out of its shielded cask. Results from calculations have been compared to measurements performed with chemical dosimeters. Comparative analyses have consistently shown a very good agreement between calculated and measured relative dose rate distributions and provided an improved knowledge on the gamma ray environment produced by the irradiator. (author)

Development of Remote Monitoring and a Control System Based on PLC and WebAccess for Learning Mechatronics

OpenAIRE

Wen-Jye Shyr; Te-Jen Su; Chia-Ming Lin

2013-01-01

This study develops a novel method for learning mechatronics using remote monitoring and control, based on a programmable logic controller (PLC) and WebAccess. A mechatronics module, a Web‐CAM and a PLC were integrated with WebAccess software to organize a remote laboratory. The proposed system enables users to access the Internet for remote monitoring and control of the mechatronics module via a web browser, thereby enhancing work flexibility by enabling personnel to control mechatronics equ...

Evaluation of the content and accessibility of web sites for accredited orthopaedic sports medicine fellowships.

Science.gov (United States)

Mulcahey, Mary K; Gosselin, Michelle M; Fadale, Paul D

2013-06-19

The Internet is a common source of information for orthopaedic residents applying for sports medicine fellowships, with the web sites of the American Orthopaedic Society for Sports Medicine (AOSSM) and the San Francisco Match serving as central databases. We sought to evaluate the web sites for accredited orthopaedic sports medicine fellowships with regard to content and accessibility. We reviewed the existing web sites of the ninety-five accredited orthopaedic sports medicine fellowships included in the AOSSM and San Francisco Match databases from February to March 2012. A Google search was performed to determine the overall accessibility of program web sites and to supplement information obtained from the AOSSM and San Francisco Match web sites. The study sample consisted of the eighty-seven programs whose web sites connected to information about the fellowship. Each web site was evaluated for its informational value. Of the ninety-five programs, fifty-one (54%) had links listed in the AOSSM database. Three (3%) of all accredited programs had web sites that were linked directly to information about the fellowship. Eighty-eight (93%) had links listed in the San Francisco Match database; however, only five (5%) had links that connected directly to information about the fellowship. Of the eighty-seven programs analyzed in our study, all eighty-seven web sites (100%) provided a description of the program and seventy-six web sites (87%) included information about the application process. Twenty-one web sites (24%) included a list of current fellows. Fifty-six web sites (64%) described the didactic instruction, seventy (80%) described team coverage responsibilities, forty-seven (54%) included a description of cases routinely performed by fellows, forty-one (47%) described the role of the fellow in seeing patients in the office, eleven (13%) included call responsibilities, and seventeen (20%) described a rotation schedule. Two Google searches identified direct links for

Unlocking the Potential of Web Localizers as Contributors to Image Accessibility: What Do Evaluation Tools Have to Offer?

OpenAIRE

Rodriguez Vazquez, Silvia

2015-01-01

Creating appropriate text alternatives to render images accessible in the web is a shared responsibility among all actors involved in the web development cycle, including web localization professionals. However, they often lack the knowledge needed to correctly transfer image accessibility across different website language versions. In this paper, we provide insight into translators' performance as regards their accessibility achievements during text alternatives adaptation from English into ...

Evaluation of Spectrum Usage for GSM band in Indoor and Outdoor Scenario for Dynamic Spectrum Access

DEFF Research Database (Denmark)

Patil, Kishor P.; Barge, Snehal; Skouby, Knud Erik

2013-01-01

, and transmit power. Several measurements have shown that the current spectrum is inefficiently utilized. The inefficient utilization problem can be solved with the help of Dynamic Spectrum Access. This paper describes the GSM band measurement conducted at different locations. In this paper, we report detailed...... measurement results of GSM band including statistical as well as spectral occupancy details obtained from measurement campaign conducted in Pune, India for indoor and outdoor scenarios. The results can be further used as an input for spectrum regulator for considering Cognitive Radio (CR) operation in GSM...

Accessibility Trends among Academic Library and Library School Web Sites in the USA and Canada

Science.gov (United States)

Schmetzke, Axel; Comeaux, David

2009-01-01

This paper focuses on the accessibility of North American library and library school Web sites for all users, including those with disabilities. Web accessibility data collected in 2006 are compared to those of 2000 and 2002. The findings of this follow-up study continue to give cause for concern: Despite improvements since 2002, library and…

Development, implementation and pilot evaluation of a Web-based Virtual Patient Case Simulation environment – Web-SP

OpenAIRE

Boberg Jonas; Johnson Gunilla; Zary Nabil; Fors Uno GH

2006-01-01

Abstract Background The Web-based Simulation of Patients (Web-SP) project was initiated in order to facilitate the use of realistic and interactive virtual patients (VP) in medicine and healthcare education. Web-SP focuses on moving beyond the technology savvy teachers, when integrating simulation-based education into health sciences curricula, by making the creation and use of virtual patients easier. The project strives to provide a common generic platform for design/creation, management, e...

Enhancing food engineering education with interactive web-based simulations

Directory of Open Access Journals (Sweden)

Alexandros Koulouris

2015-04-01

Full Text Available In the traditional deductive approach in teaching any engineering topic, teachers would first expose students to the derivation of the equations that govern the behavior of a physical system and then demonstrate the use of equations through a limited number of textbook examples. This methodology, however, is rarely adequate to unmask the cause-effect and quantitative relationships between the system variables that the equations embody. Web-based simulation, which is the integration of simulation and internet technologies, has the potential to enhance the learning experience by offering an interactive and easily accessible platform for quick and effortless experimentation with physical phenomena.This paper presents the design and development of a web-based platform for teaching basic food engineering phenomena to food technology students. The platform contains a variety of modules (“virtual experiments” covering the topics of mass and energy balances, fluid mechanics and heat transfer. In this paper, the design and development of three modules for mass balances and heat transfer is presented. Each webpage representing an educational module has the following features: visualization of the studied phenomenon through graphs, charts or videos, computation through a mathematical model and experimentation.  The student is allowed to edit key parameters of the phenomenon and observe the effect of these changes on the outputs. Experimentation can be done in a free or guided fashion with a set of prefabricated examples that students can run and self-test their knowledge by answering multiple-choice questions.

Page sample size in web accessibility testing: how many pages is enough?

NARCIS (Netherlands)

Velleman, Eric Martin; van der Geest, Thea

2013-01-01

Various countries and organizations use a different sampling approach and sample size of web pages in accessibility conformance tests. We are conducting a systematic analysis to determine how many pages is enough for testing whether a website is compliant with standard accessibility guidelines. This

Access and completion of a Web-based treatment in a population-based sample of tornado-affected adolescents.

Science.gov (United States)

Price, Matthew; Yuen, Erica K; Davidson, Tatiana M; Hubel, Grace; Ruggiero, Kenneth J

2015-08-01

Although Web-based treatments have significant potential to assess and treat difficult-to-reach populations, such as trauma-exposed adolescents, the extent that such treatments are accessed and used is unclear. The present study evaluated the proportion of adolescents who accessed and completed a Web-based treatment for postdisaster mental health symptoms. Correlates of access and completion were examined. A sample of 2,000 adolescents living in tornado-affected communities was assessed via structured telephone interview and invited to a Web-based treatment. The modular treatment addressed symptoms of posttraumatic stress disorder, depression, and alcohol and tobacco use. Participants were randomized to experimental or control conditions after accessing the site. Overall access for the intervention was 35.8%. Module completion for those who accessed ranged from 52.8% to 85.6%. Adolescents with parents who used the Internet to obtain health-related information were more likely to access the treatment. Adolescent males were less likely to access the treatment. Future work is needed to identify strategies to further increase the reach of Web-based treatments to provide clinical services in a postdisaster context. (c) 2015 APA, all rights reserved).

Web-based Interactive Simulator for Rotating Machinery.

Science.gov (United States)

Sirohi, Vijayalaxmi

1999-01-01

Baroma (Balance of Rotating Machinery), the Web-based educational engineering interactive software for teaching/learning combines didactical and software ergonomical approaches. The software in tutorial form simulates a problem using Visual Interactive Simulation in graphic display, and animation is brought about through graphical user interface…

Simulator Posisi Matahari dan Bulan Berbasis Web dengan WebGL

Directory of Open Access Journals (Sweden)

Kamshory

2014-09-01

Full Text Available Moon as a satellite of the earth has an important role for the life of the earth. Apart from being a source of illumination, moon also has an effect on the earth both on land and at sea. The influence of the moon to the earth relate to the its position. This research aims to create a simulator of the sun and moon position to the earth based on the time and location of the observation. This simulator is web-based and made in 3-dimensional (3D using webGL technology. The position of the sun and moon expressed by latitude and longitude which is a position that is passed by the line connecting the earth to the sun or the line connecting the earth to the moon. The position of the sun and moon obtained from calculations based on previous research. Once the position is known, the earth, the sun, and the moon then described as a 3-D model. The position of the camera can be moved by dragging a web page so that the sun, earth, and moon can be seen from various positions. The camera always leads to the center of the earth to avoid user errors flipping the camera which causes the object is not visible.

Development of Remote Monitoring and a Control System Based on PLC and WebAccess for Learning Mechatronics

Directory of Open Access Journals (Sweden)

Wen-Jye Shyr

2013-02-01

Full Text Available This study develops a novel method for learning mechatronics using remote monitoring and control, based on a programmable logic controller (PLC and WebAccess. A mechatronics module, a Web-CAM and a PLC were integrated with WebAccess software to organize a remote laboratory. The proposed system enables users to access the Internet for remote monitoring and control of the mechatronics module via a web browser, thereby enhancing work flexibility by enabling personnel to control mechatronics equipment from a remote location. Mechatronics control and long-distance monitoring were realized by establishing communication between the PLC and WebAccess. Analytical results indicate that the proposed system is feasible. The suitability of this system is demonstrated in the department of industrial education and technology at National Changhua University of Education, Taiwan. Preliminary evaluation of the system was encouraging and has shown that it has achieved success in helping students understand concepts and master remote monitoring and control techniques.

SED-ML web tools: generate, modify and export standard-compliant simulation studies.

Science.gov (United States)

Bergmann, Frank T; Nickerson, David; Waltemath, Dagmar; Scharm, Martin

2017-04-15

The Simulation Experiment Description Markup Language (SED-ML) is a standardized format for exchanging simulation studies independently of software tools. We present the SED-ML Web Tools, an online application for creating, editing, simulating and validating SED-ML documents. The Web Tools implement all current SED-ML specifications and, thus, support complex modifications and co-simulation of models in SBML and CellML formats. Ultimately, the Web Tools lower the bar on working with SED-ML documents and help users create valid simulation descriptions. http://sysbioapps.dyndns.org/SED-ML_Web_Tools/ . fbergman@caltech.edu . © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Admission Control and Interference Management in Dynamic Spectrum Access Networks

Directory of Open Access Journals (Sweden)

Jorge Martinez-Bauset

2010-01-01

Full Text Available We study two important aspects to make dynamic spectrum access work in practice: the admission policy of secondary users (SUs to achieve a certain degree of quality of service and the management of the interference caused by SUs to primary users (PUs. In order to limit the forced termination probability of SUs, we evaluate the Fractional Guard Channel reservation scheme to give priority to spectrum handovers over new arrivals. We show that, contrary to what has been proposed, the throughput of SUs cannot be maximized by configuring the reservation parameter. We also study the interference caused by SUs to PUs. We propose and evaluate different mechanisms to reduce the interference, which are based on simple spectrum access algorithms for both PUs and SUs and channel repacking algorithms for SUs. Numerical results show that the reduction can be of one order of magnitude or more with respect to the random access case. Finally, we propose an adaptive admission control scheme that is able to limit simultaneously the forced termination probability of SUs and what we define as the probability of interference. Our scheme does not require any configuration parameters beyond the probability objectives. Besides, it is simple to implement and it can operate with any arrival process and distribution of the session duration.

THREE-DIMENSIONAL WEB-BASED PHYSICS SIMULATION APPLICATION FOR PHYSICS LEARNING TOOL

Directory of Open Access Journals (Sweden)

William Salim

2012-10-01

Full Text Available The purpose of this research is to present a multimedia application for doing simulation in Physics. The application is a web based simulator that implementing HTML5, WebGL, and JavaScript. The objects and the environment will be in three dimensional views. This application is hoped will become the substitute for practicum activity. The current development is the application only covers Newtonian mechanics. Questionnaire and literature study is used as the data collecting method. While Waterfall Method used as the design method. The result is Three-DimensionalPhysics Simulator as online web application. Three-Dimensionaldesign and mentor-mentee relationship is the key features of this application. The conclusion made is Three-DimensionalPhysics Simulator already fulfilled in both design and functionality according to user. This application also helps them to understand Newtonian mechanics by simulation. Improvements are needed, because this application only covers Newtonian Mechanics. There is a lot possibility in the future that this simulation can also covers other Physics topic, such as optic, energy, or electricity.Keywords: Simulation, Physic, Learning Tool, HTML5, WebGL

WMT: The CSDMS Web Modeling Tool

Science.gov (United States)

Piper, M.; Hutton, E. W. H.; Overeem, I.; Syvitski, J. P.

2015-12-01

The Community Surface Dynamics Modeling System (CSDMS) has a mission to enable model use and development for research in earth surface processes. CSDMS strives to expand the use of quantitative modeling techniques, promotes best practices in coding, and advocates for the use of open-source software. To streamline and standardize access to models, CSDMS has developed the Web Modeling Tool (WMT), a RESTful web application with a client-side graphical interface and a server-side database and API that allows users to build coupled surface dynamics models in a web browser on a personal computer or a mobile device, and run them in a high-performance computing (HPC) environment. With WMT, users can: Design a model from a set of components Edit component parameters Save models to a web-accessible server Share saved models with the community Submit runs to an HPC system Download simulation results The WMT client is an Ajax application written in Java with GWT, which allows developers to employ object-oriented design principles and development tools such as Ant, Eclipse and JUnit. For deployment on the web, the GWT compiler translates Java code to optimized and obfuscated JavaScript. The WMT client is supported on Firefox, Chrome, Safari, and Internet Explorer. The WMT server, written in Python and SQLite, is a layered system, with each layer exposing a web service API: wmt-db: database of component, model, and simulation metadata and output wmt-api: configure and connect components wmt-exe: launch simulations on remote execution servers The database server provides, as JSON-encoded messages, the metadata for users to couple model components, including descriptions of component exchange items, uses and provides ports, and input parameters. Execution servers are network-accessible computational resources, ranging from HPC systems to desktop computers, containing the CSDMS software stack for running a simulation. Once a simulation completes, its output, in NetCDF, is packaged

Simulation Study on Identifiability of UHE Gamma-ray Air Showers

International Nuclear Information System (INIS)

Wada, Y.; Inoue, N.; Miyazawa, K.; Vankov, H.P.

2008-01-01

The chemical composition of Ultra-High-Energy (UHE) comic rays is one of unsolved mysteries, and its study will give us fruitful information on the origin and acceleration mechanism of UHE cosmic rays. Especially, a detection of UHE gamma-rays by hybrid experiments, such as AUGER and TA, will be a key to solve these questions. The characteristics of UHE gamma-ray showers have been studied by comparing the lateral and longitudinal structures of shower particles calculated with AIRES and our own simulation code, so far. There are apparent differences in a slope of lateral distribution (η) and a depth of shower maximum (Xmax) between gamma-ray and proton induced showers because UHE gamma-ray showers are affected by the LPM effect and the geomagnetic cascading process in an energy region of >10 19.5 eV. Different features between gamma-ray and proton showers are pointed out from the simulation study and an identifiability of gamma-ray showers from proton ones is also discussed by the method of Neural-Network-Analysis

Simulation Study on Identifiability of UHE Gamma-ray Air Showers

Energy Technology Data Exchange (ETDEWEB)

Wada, Y.; Inoue, N.; Miyazawa, K. [Graduate School of Science and Engineering, Saitama University, Saitama 338-8570 (Japan); Vankov, H.P. [Institute for Nuclear Research and Nuclear Energy, Bulgaria Academy, Sofia (Bulgaria)

2008-01-15

The chemical composition of Ultra-High-Energy (UHE) comic rays is one of unsolved mysteries, and its study will give us fruitful information on the origin and acceleration mechanism of UHE cosmic rays. Especially, a detection of UHE gamma-rays by hybrid experiments, such as AUGER and TA, will be a key to solve these questions. The characteristics of UHE gamma-ray showers have been studied by comparing the lateral and longitudinal structures of shower particles calculated with AIRES and our own simulation code, so far. There are apparent differences in a slope of lateral distribution ({eta}) and a depth of shower maximum (Xmax) between gamma-ray and proton induced showers because UHE gamma-ray showers are affected by the LPM effect and the geomagnetic cascading process in an energy region of >10{sup 19.5}eV. Different features between gamma-ray and proton showers are pointed out from the simulation study and an identifiability of gamma-ray showers from proton ones is also discussed by the method of Neural-Network-Analysis.

mORCA: ubiquitous access to life science web services.

Science.gov (United States)

Diaz-Del-Pino, Sergio; Trelles, Oswaldo; Falgueras, Juan

2018-01-16

Technical advances in mobile devices such as smartphones and tablets have produced an extraordinary increase in their use around the world and have become part of our daily lives. The possibility of carrying these devices in a pocket, particularly mobile phones, has enabled ubiquitous access to Internet resources. Furthermore, in the life sciences world there has been a vast proliferation of data types and services that finish as Web Services. This suggests the need for research into mobile clients to deal with life sciences applications for effective usage and exploitation. Analysing the current features in existing bioinformatics applications managing Web Services, we have devised, implemented, and deployed an easy-to-use web-based lightweight mobile client. This client is able to browse, select, compose parameters, invoke, and monitor the execution of Web Services stored in catalogues or central repositories. The client is also able to deal with huge amounts of data between external storage mounts. In addition, we also present a validation use case, which illustrates the usage of the application while executing, monitoring, and exploring the results of a registered workflow. The software its available in the Apple Store and Android Market and the source code is publicly available in Github. Mobile devices are becoming increasingly important in the scientific world due to their strong potential impact on scientific applications. Bioinformatics should not fall behind this trend. We present an original software client that deals with the intrinsic limitations of such devices and propose different guidelines to provide location-independent access to computational resources in bioinformatics and biomedicine. Its modular design makes it easily expandable with the inclusion of new repositories, tools, types of visualization, etc.

Designing A General Deep Web Access Approach Based On A Newly Introduced Factor; Harvestability Factor (HF)

NARCIS (Netherlands)

Khelghati, Mohammadreza; van Keulen, Maurice; Hiemstra, Djoerd

2014-01-01

The growing need of accessing more and more information draws attentions to huge amount of data hidden behind web forms defined as deep web. To make this data accessible, harvesters have a crucial role. Targeting different domains and websites enhances the need to have a general-purpose harvester

Determination of correction factors for borehole natural gamma-ray measurements by Monte Carlo simulations

NARCIS (Netherlands)

Maucec, M.; Hendriks, Peter; Limburg, J.; de Meijer, R. J.

2009-01-01

The analysis of natural gamma-ray spectra measured in boreholes has to take into account borehole parameters such as the presence of casings and borehole diameter. For large, high-efficiency gamma-ray detectors, such as BGO-based systems, which employ full-spectrum data analysis, corresponding

Interactive Web-based e-learning for Studying Flexible Manipulator Systems

Directory of Open Access Journals (Sweden)

Abul K. M. Azad

2008-03-01

Full Text Available Abstract— This paper presents a web-based e-leaning facility for simulation, modeling, and control of flexible manipulator systems. The simulation and modeling part includes finite difference and finite element simulations along with neural network and genetic algorithm based modeling strategies for flexible manipulator systems. The controller part constitutes a number of open-loop and closed-loop designs. Closed loop control designs include the classical, adaptive, and neuro-model based strategies. Matlab software package and its associated toolboxes are used to implement these. The Matlab web server is used as the gateway between the facility and web-access. ASP.NET technology and SQL database are utilized to develop web applications for access control, user account and password maintenance, administrative management, and facility utilization monitoring. The reported facility provides a flexible but effective approach of web-based interactive e-learning facility of an engineering system. This can be extended to incorporate additional engineering systems within the e-learning framework.

A novel natural environment background model for Monte Carlo simulation and its application in the simulation of anticoincidence measurement.

Science.gov (United States)

Li, Sangang; Wang, Lei; Cheng, Yi; Tuo, Xianguo; Liu, Mingzhe; Yao, Fuliang; Leng, Fengqing; Cheng, Yuanyuan; Cai, Ting; Zhou, Yan

2016-02-01

This study proposes a novel natural environment background model by modeling brief environment conditions. It uses Geant4 program to simulate decays of (238)U, (232)Th, and (40)K in soil and obtains compositions of different-energy gamma rays in the natural environment background. The simulated gamma spectrum of the natural environment background agrees well with the experimental spectrum, particularly above 250 keV. The model is used in the simulation of anticoincidence measurement, indicating that the natural environment background can be decreased by approximately 88%, and the Compton attenuation factor is 2.22. The simulation of anticoincidence measurement can improve the minimum detectable activity (MDA) of the detection system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Checking an integrated model of web accessibility and usability evaluation for disabled people.

Science.gov (United States)

Federici, Stefano; Micangeli, Andrea; Ruspantini, Irene; Borgianni, Stefano; Corradi, Fabrizio; Pasqualotto, Emanuele; Olivetti Belardinelli, Marta

2005-07-08

A combined objective-oriented and subjective-oriented method for evaluating accessibility and usability of web pages for students with disability was tested. The objective-oriented approach is devoted to verifying the conformity of interfaces to standard rules stated by national and international organizations responsible for web technology standardization, such as W3C. Conversely, the subjective-oriented approach allows assessing how the final users interact with the artificial system, accessing levels of user satisfaction based on personal factors and environmental barriers. Five kinds of measurements were applied as objective-oriented and subjective-oriented tests. Objective-oriented evaluations were performed on the Help Desk web page for students with disability, included in the website of a large Italian state university. Subjective-oriented tests were administered to 19 students labeled as disabled on the basis of their own declaration at the University enrolment: 13 students were tested by means of the SUMI test and six students by means of the 'Cooperative evaluation'. Objective-oriented and subjective-oriented methods highlighted different and sometimes conflicting results. Both methods have pointed out much more consistency regarding levels of accessibility than of usability. Since usability is largely affected by individual differences in user's own (dis)abilities, subjective-oriented measures underscored the fact that blind students encountered much more web surfing difficulties.

Wavenumber spectrum of whistler turbulence: Particle-in-cell simulation

International Nuclear Information System (INIS)

Saito, S.; Gary, S. Peter; Narita, Y.

2010-01-01

The forward cascade of decaying whistler turbulence is studied in low beta plasma to understand essential properties of the energy spectrum at electron scales, by using a two-dimensional electromagnetic particle-in-cell (PIC) simulation. This simulation demonstrates turbulence in which the energy cascade rate is greater than the dissipation rate at the electron inertial length. The PIC simulation shows that the magnetic energy spectrum of forward-cascaded whistler turbulence at electron inertial scales is anisotropic and develops a very steep power-law spectrum which is consistent with recent solar wind observations. A comparison of the simulated spectrum with that predicted by a phenomenological turbulence scaling model suggests that the energy cascade at the electron inertial scale depends on both magnetic fluctuations and electron velocity fluctuations, as well as on the whistler dispersion relation. Thus, not only kinetic Alfven turbulence but also whistler turbulence may explain recent solar wind observations of very steep magnetic spectra at short scales.

Design and Implementation of Open-Access Web-Based Education ...

African Journals Online (AJOL)

... is not flexible as it does not permit access to educational resource at any time or place feasible. ... In this paper, a web-based education useful for e-learning was designed and ... using an open source platform which will be more flexible, and cost effective due to free licensing. The programming languages used are. VB.

Building interactive simulations in a Web page design program.

Science.gov (United States)

Kootsey, J Mailen; Siriphongs, Daniel; McAuley, Grant

2004-01-01

A new Web software architecture, NumberLinX (NLX), has been integrated into a commercial Web design program to produce a drag-and-drop environment for building interactive simulations. NLX is a library of reusable objects written in Java, including input, output, calculation, and control objects. The NLX objects were added to the palette of available objects in the Web design program to be selected and dropped on a page. Inserting an object in a Web page is accomplished by adding a template block of HTML code to the page file. HTML parameters in the block must be set to user-supplied values, so the HTML code is generated dynamically, based on user entries in a popup form. Implementing the object inspector for each object permits the user to edit object attributes in a form window. Except for model definition, the combination of the NLX architecture and the Web design program permits construction of interactive simulation pages without writing or inspecting code.

Web-based, GPU-accelerated, Monte Carlo simulation and visualization of indirect radiation imaging detector performance.

Science.gov (United States)

Dong, Han; Sharma, Diksha; Badano, Aldo

2014-12-01

Monte Carlo simulations play a vital role in the understanding of the fundamental limitations, design, and optimization of existing and emerging medical imaging systems. Efforts in this area have resulted in the development of a wide variety of open-source software packages. One such package, hybridmantis, uses a novel hybrid concept to model indirect scintillator detectors by balancing the computational load using dual CPU and graphics processing unit (GPU) processors, obtaining computational efficiency with reasonable accuracy. In this work, the authors describe two open-source visualization interfaces, webmantis and visualmantis to facilitate the setup of computational experiments via hybridmantis. The visualization tools visualmantis and webmantis enable the user to control simulation properties through a user interface. In the case of webmantis, control via a web browser allows access through mobile devices such as smartphones or tablets. webmantis acts as a server back-end and communicates with an NVIDIA GPU computing cluster that can support multiuser environments where users can execute different experiments in parallel. The output consists of point response and pulse-height spectrum, and optical transport statistics generated by hybridmantis. The users can download the output images and statistics through a zip file for future reference. In addition, webmantis provides a visualization window that displays a few selected optical photon path as they get transported through the detector columns and allows the user to trace the history of the optical photons. The visualization tools visualmantis and webmantis provide features such as on the fly generation of pulse-height spectra and response functions for microcolumnar x-ray imagers while allowing users to save simulation parameters and results from prior experiments. The graphical interfaces simplify the simulation setup and allow the user to go directly from specifying input parameters to receiving visual

Application of full spectrum analysis technique for NaI(TI) based gamma ray spectral monitoring system

International Nuclear Information System (INIS)

Pant, Amar D.; Verma, Amit K.; Narayani, K.; Anilkumar, S.; Singh, Rajvir

2016-01-01

NaI(Tl) is commonly used for the gamma spectrometry analysis in laboratories. It continues to be the first choice for gamma spectrometry in many applications even today. Many gamma spectrometric methods are developed to experimentally determine activity of radionuclides in samples. Detectors used worldwide for gamma radiation monitoring are either GM based or scintillator based detector based on count rate. For radiation early warning systems radionuclide specific radiation monitoring methodology is required i.e. gamma ray spectrometry based environmental monitoring system. A computer program has been developed for gamma spectral monitoring by the use of full spectrum analysis (FSA). In this measured spectra are fitted using individual spectral components by least square fitting (LSF). The method is found very useful in situations, where radionuclide specific environmental radiation monitoring is required. The paper describes the details of the FSA procedure for the on line acquisition and analysis of gamma ray spectra from Nal(Tl) detectors

Increased power of resting-state gamma oscillations in autism spectrum disorder detected by routine electroencephalography

NARCIS (Netherlands)

van Diessen, Eric; Senders, Joeky; Jansen, Floor E.; Boersma, Maria; Bruining, Hilgo

2015-01-01

Experimental studies suggest that increased resting-state power of gamma oscillations is associated with autism spectrum disorder (ASD). To extend the clinical applicability of this finding, we retrospectively investigated routine electroencephalography (EEG) recordings of 19 patients with ASD and

Monte Carlo simulation of gamma ray tomography for image reconstruction

Energy Technology Data Exchange (ETDEWEB)

Guedes, Karlos A.N.; Moura, Alex; Dantas, Carlos; Melo, Silvio; Lima, Emerson, E-mail: karlosguedes@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Meric, Ilker [University of Bergen (Norway)

2015-07-01

The Monte Carlo simulations of known density and shape object was validate with Gamma Ray Tomography in static experiments. An aluminum half-moon piece placed inside a steel pipe was the MC simulation test object that was also measured by means of gamma ray transmission. Wall effect of the steel pipe due to irradiation geometry in a single pair source-detector tomography was evaluated by comparison with theoretical data. MCNPX code requires a defined geometry to each photon trajectory which practically prevents this usage for tomography reconstruction simulation. The solution was found by writing a program in Delphi language to create input files automation code. Simulations of tomography data by automated MNCPX code were carried out and validated by experimental data. Working in this sequence the produced data needed a databank to be stored. Experimental setup used a Cesium-137 isotopic radioactive source (7.4 × 109 Bq), and NaI(Tl) scintillation detector of (51 × 51) × 10−3 m crystal size coupled to a multichannel analyzer. A stainless steel tubes of 0,154 m internal diameter, 0.014 m thickness wall. The results show that the MCNPX simulation code adapted to automated input file is useful for generating a matrix data M(θ,t), of a computerized gamma ray tomography for any known density and regular shape object. Experimental validation used RMSE from gamma ray paths and from attenuation coefficient data. (author)

Building Interactive Simulations in Web Pages without Programming.

Science.gov (United States)

Mailen Kootsey, J; McAuley, Grant; Bernal, Julie

2005-01-01

A software system is described for building interactive simulations and other numerical calculations in Web pages. The system is based on a new Java-based software architecture named NumberLinX (NLX) that isolates each function required to build the simulation so that a library of reusable objects could be assembled. The NLX objects are integrated into a commercial Web design program for coding-free page construction. The model description is entered through a wizard-like utility program that also functions as a model editor. The complete system permits very rapid construction of interactive simulations without coding. A wide range of applications are possible with the system beyond interactive calculations, including remote data collection and processing and collaboration over a network.

Simulating 60 Co gamma irradiation systems

International Nuclear Information System (INIS)

Omi, Nelson M.; Rela, Paulo R.

2000-01-01

The use of Cadgamma, a software dedicated to simulate 60 Co gamma irradiation systems, can lead to an optimized process and simulating, in a few hours, many configurations setups for the irradiation elements. The software can also simulate changes in the path of the product and the influence of any steady body like the support of the product support and source shoulders. These simulations minimize the number of dose mapping tests in industrial applications and allow the study of unusual setups. Cadgamma was developed at IPEN to simulate it is multipurpose 60 Co irradiation system, under construction and planned to be operating by the second half of 2001. The software was used on project stage and will help to optimize the irradiation process for each product to be treated. (author)

A comparison of semiconductor gamma spectrometric analysis using the peak net area calculations and the whole spectrum processing

International Nuclear Information System (INIS)

Krnac, S.; Koskelo, M.; Venkatamaran, R.

1998-01-01

This study was conducted to compare the results of gamma spectrometric analysis using the Scaling Confirmatory Factor Analysis (SCFA) method to that of Genie2K, which uses a more traditional method. Gamma ray spectra had had been acquired for several gamma standard sources, all of which except Co-57 and Eu-152 being single gamma ray emitting nuclides. These standard sources spanned the energy range from 60 keV (Am-241) to 1116 keV (Zn-65). The standard sources were counted at 3 different geometries at 3 different geometries, with source-detector distances of 0, 5, and 15 cm. Using single gamma ray spectra collected at a given counting geometry, and the certificate file, an efficiency calibration was created for that geometry. Three different test spectra, one for each counting geometry, had been created by combining several of the standard source spectra. The efficiency calibrations created for the 3 geometries were loaded into the respective spectrum files. Each test spectrum was analyzed using the standard Genie2K engines; Peak locate, Peak search, Interactive peak fit, Background subs-traction, Efficiency correction, and Nuclide Identification with interference analysis. The results of the various calculation steps were reported. In all 3 test cases, the SCFA method identified all the nuclides correctly. The K-40 activities calculated by the SCFA method were reasonably close to that from Genie2K analysis. In general, the quantitative results of the SCFA method were impressive in all 3 cases. On a positive note, the SCFA method did identify low yield gamma lines in Eu-152, which were not identified by the Genie2K analysis. This substantiates claim that the SCFA is more sensitive than the traditional method of spectrum analysis. (authors)

CNA web server: rigidity theory-based thermal unfolding simulations of proteins for linking structure, (thermo-)stability, and function.

Science.gov (United States)

Krüger, Dennis M; Rathi, Prakash Chandra; Pfleger, Christopher; Gohlke, Holger

2013-07-01

The Constraint Network Analysis (CNA) web server provides a user-friendly interface to the CNA approach developed in our laboratory for linking results from rigidity analyses to biologically relevant characteristics of a biomolecular structure. The CNA web server provides a refined modeling of thermal unfolding simulations that considers the temperature dependence of hydrophobic tethers and computes a set of global and local indices for quantifying biomacromolecular stability. From the global indices, phase transition points are identified where the structure switches from a rigid to a floppy state; these phase transition points can be related to a protein's (thermo-)stability. Structural weak spots (unfolding nuclei) are automatically identified, too; this knowledge can be exploited in data-driven protein engineering. The local indices are useful in linking flexibility and function and to understand the impact of ligand binding on protein flexibility. The CNA web server robustly handles small-molecule ligands in general. To overcome issues of sensitivity with respect to the input structure, the CNA web server allows performing two ensemble-based variants of thermal unfolding simulations. The web server output is provided as raw data, plots and/or Jmol representations. The CNA web server, accessible at http://cpclab.uni-duesseldorf.de/cna or http://www.cnanalysis.de, is free and open to all users with no login requirement.

Web accessibility: a longitudinal study of college and university home pages in the northwestern United States.

Science.gov (United States)

Thompson, Terrill; Burgstahler, Sheryl; Moore, Elizabeth J

2010-01-01

This article reports on a follow-up assessment to Thompson et al. (Proceedings of The First International Conference on Technology-based Learning with Disability, July 19-20, Dayton, Ohio, USA; 2007. pp 127-136), in which higher education home pages were evaluated over a 5-year period on their accessibility to individuals with disabilities. The purpose of this article is to identify trends in web accessibility and long-term impact of outreach and education. Home pages from 127 higher education institutions in the Northwest were evaluated for accessibility three times over a 6-month period in 2004-2005 (Phase I), and again in 2009 (Phase II). Schools in the study were offered varying degrees of training and/or support on web accessibility during Phase I. Pages were evaluated for accessibility using a set of manual checkpoints developed by the researchers. Over the 5-year period reported in this article, significant positive gains in accessibility were revealed on some measures, but accessibility declined on other measures. The areas of improvement are arguably the more basic, easy-to-implement accessibility features, while the area of decline is keyboard accessibility, which is likely associated with the emergence of dynamic new technologies on web pages. Even on those measures where accessibility is improving, it is still strikingly low. In Phase I of the study, institutions that received extensive training and support were more likely than other institutions to show improved accessibility on the measures where institutions improved overall, but were equally or more likely than others to show a decline on measures where institutions showed an overall decline. In Phase II, there was no significant difference between institutions who had received support earlier in the study, and those who had not. Results suggest that growing numbers of higher education institutions in the Northwest are motivated to add basic accessibility features to their home pages, and that

Prognoses of prospective areas for uranium metallogenesis with full-spectrum information of airborne gamma-ray survey

International Nuclear Information System (INIS)

Hu Mingkao; Shen Zhengxin; Li Binghai; Cai Genqing

2010-01-01

This paper briefly introduces the development of airborne radioactive survey and the background of carrying out full-spectrum study. It also introduces the method, standard and application example of using the full-spectrum information of airborne gamma spectrum to predict U-metallogenic prospective areas. The field checking has found that uranium in the water of the prospective area is three magnitude higher than that in the normal area. The developmment and the application of this method will play a multiplier role in reusing the library stored data evaluating uranium resource potential in our Country. (authors)

Spectrum and frequency of chlorophyll mutations in urdbean (Vigna mungo L. Hepper) induced by EMS and gamma rays

International Nuclear Information System (INIS)

Sharma, A.K.; Singh, V.P.; Sarma, M.K.

2006-01-01

In mutation breeding experiment, plants with altered characteristics such as chlorophyll changes, sterility, plant lethality etc. could be the marker of the mutability of a variety. In fact, spectrum and frequency of chlorophyll mutations have been studied in the great detail. The chlorophyll mutation is the clear-cut indication of non-directional nature of mutation and possibility of induction of useful mutations. The spectrum and frequency of chlorophyll mutation was estimated by using gamma rays (100, 200, 300 and 400 Gy doses), EMS (0.2, 0.4, 0.6 and 0.8%) and combination of gamma rays (100, 200, 300 400 Gy) with 0.2 % concentration EMS on two cultivars, namely, Pant Urd-19 and Pant Urd-30 of urdbean ( Vigna mungo L. Hepper). Five different types of chlorophyll mutations viz., albina, xantha, viridis, chlorina and maculata were identified in both the cultivars. Almost all the combination treatments produced maximum frequency and wider spectrum of chlorophyll mutations followed by single treatment of gamma rays or EMS. The frequency of chlorophyll mutation increased with higher doses of mutagens but decreased at highest dose. Proc. Nat. Acad. Sci. India. 76(8), I, 2006. 64-68. (author)

78 FR 67881 - Nondiscrimination on the Basis of Disability in Air Travel: Accessibility of Web Sites and...

Science.gov (United States)

2013-11-12

... ticket agents are providing schedule and fare information and marketing covered air transportation... corresponding accessible pages on a mobile Web site by one year after the final rule's effective date; and (3... criteria) as the required accessibility standard for all public-facing Web pages involved in marketing air...

Accessing and Selecting Word Meaning in Autism Spectrum Disorder

Science.gov (United States)

Henderson, L. M.; Clarke, P. J.; Snowling, M. J.

2011-01-01

Background: Comprehension difficulties are commonly reported in autism spectrum disorder (ASD) but the causes of these difficulties are poorly understood. This study investigates how children with ASD access and select meanings of ambiguous words to test four hypotheses regarding the nature of their comprehension difficulties: semantic deficit,…

Extensive air showers accompanied by gamma-families and fraction of protons in the primary cosmic rays

International Nuclear Information System (INIS)

Hamayasu, C.; Saito, To.; Sakata, M.

1987-01-01

Experimental data of EAS accompanied by gamma-families with a total energy greater than 10 TeV are taken at Mt. Norikura in 1980 -- 1981 and in 1985. An EX (emulsion and/or x-ray film) chamber is used, which consists six sensitive layers and iron plates as the absorber. The iron absorber chamber can detect more hadron origin cascades than a lead absorber chamber for the same chamber thickness in radiation length, though disadvantageous for separation of gamma-ray origin cascades from hadron origin ones. Analysis is made of the single gamma-ray energy spectrum, integral spectrum of total energies of gamma-families, zenith angle distributions of gamma-families, the scatter plot of EAS size - ΣE γ,H correlation, arrival zenith angle distribution of general EAS, and depth dependence of absolute vertical intensities of EAS. The data obtained are compared by the Monte Carlo simulation technique with a moderate rising cross section proportional to the collision energy in the form E 0.04 for p-air nucleus collisions. The absolute intensity of size spectrum of such EAS is strongly affected by the fraction of primary protonsin the 10 15 -- 10 16 eV region. The experimental size spectrum agrees with the simulated spectrum for the p-poor (up to 15 %) primary composition but it disagrees with the p-rich (up to 40 %) one in the first half, at least, of this energy region. (Nogami, K.)

Using a Web GIS Plate Tectonics Simulation to Promote Geospatial Thinking

Science.gov (United States)

Bodzin, Alec M.; Anastasio, David; Sharif, Rajhida; Rutzmoser, Scott

2016-01-01

Learning with Web-based geographic information system (Web GIS) can promote geospatial thinking and analysis of georeferenced data. Web GIS can enable learners to analyze rich data sets to understand spatial relationships that are managed in georeferenced data visualizations. We developed a Web GIS plate tectonics simulation as a capstone learning…

Motivational Effect of Web-Based Simulation Game in Teaching Operations Management

Science.gov (United States)

Nguyen, Tung Nhu

2015-01-01

Motivational effects during a simulated educational game should be studied because a general concern of lecturers is motivating students and increasing their knowledge. Given advances in internet technology, traditional short in-class games are being substituted with long web-based games. To maximize the benefits of web-based simulation games, a…

Search, Read and Write: An Inquiry into Web Accessibility for People with Dyslexia.

Science.gov (United States)

Berget, Gerd; Herstad, Jo; Sandnes, Frode Eika

2016-01-01

Universal design in context of digitalisation has become an integrated part of international conventions and national legislations. A goal is to make the Web accessible for people of different genders, ages, backgrounds, cultures and physical, sensory and cognitive abilities. Political demands for universally designed solutions have raised questions about how it is achieved in practice. Developers, designers and legislators have looked towards the Web Content Accessibility Guidelines (WCAG) for answers. WCAG 2.0 has become the de facto standard for universal design on the Web. Some of the guidelines are directed at the general population, while others are targeted at more specific user groups, such as the visually impaired or hearing impaired. Issues related to cognitive impairments such as dyslexia receive less attention, although dyslexia is prevalent in at least 5-10% of the population. Navigation and search are two common ways of using the Web. However, while navigation has received a fair amount of attention, search systems are not explicitly included, although search has become an important part of people's daily routines. This paper discusses WCAG in the context of dyslexia for the Web in general and search user interfaces specifically. Although certain guidelines address topics that affect dyslexia, WCAG does not seem to fully accommodate users with dyslexia.

Framework for TV white space spectrum access in Southern African Development Community (SADC)

CSIR Research Space (South Africa)

Masonta, MT

2013-09-01

Full Text Available The global migration of television (TV) from analogue to digital broadcast will see a large amount of TV spectrum available (called TV white space - TVWS) for other services such as mobile and broadband wireless access (BWA). Leading spectrum...

Gamma-ray spectroscopy measurements and simulations for uranium mining

Science.gov (United States)

Marchais, T.; Pérot, B.; Carasco, C.; Allinei, P.-G.; Chaussonnet, P.; Ma, J.-L.; Toubon, H.

2018-01-01

AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration evaluation by means of gamma measurements. This paper reports gamma-ray spectra, recorded with a high-purity coaxial germanium detector, on standard cement blocks with increasing uranium content, and the corresponding MCNP simulations. The detailed MCNP model of the detector and experimental setup has been validated by calculation vs. experiment comparisons. An optimization of the detector MCNP model is presented in this paper, as well as a comparison of different nuclear data libraries to explain missing or exceeding peaks in the simulation. Energy shifts observed between the fluorescence X-rays produced by MCNP and atomic data are also investigated. The qualified numerical model will be used in further studies to develop new gamma spectroscopy approaches aiming at reducing acquisition times, especially for ore samples with low uranium content.

Distinguish natural sources out of secular equilibrium with their parents or daughters in Gamma ray spectrum analyses

International Nuclear Information System (INIS)

Mao Yahong; Liu Yigang

2005-01-01

Objective: To determine materials containing natural radionuclides in or out secular equilibrium with their parents or daughters. Methods: In gamma ray spectrum analyses, the activity concentration of every daughter is the same as that of its parent when the material is in secular equilibrium. The activity concentrations of daughters and their parents are different when the material is out of secular equilibrium. Results: It is different to determine whether the exposures from these materials should be exempted that materials containing natural radionuclides are in or out of secular equilibrium with their parents or daughters. Conclusion: It is important to determine materials containing natural radionuclides in or out secular equilibrium with their parents or daughters in gamma ray spectrum analyses. (authors)

Developing Access Control Model of Web OLAP over Trusted and Collaborative Data Warehouses

Science.gov (United States)

Fugkeaw, Somchart; Mitrpanont, Jarernsri L.; Manpanpanich, Piyawit; Juntapremjitt, Sekpon

This paper proposes the design and development of Role- based Access Control (RBAC) model for the Single Sign-On (SSO) Web-OLAP query spanning over multiple data warehouses (DWs). The model is based on PKI Authentication and Privilege Management Infrastructure (PMI); it presents a binding model of RBAC authorization based on dimension privilege specified in attribute certificate (AC) and user identification. Particularly, the way of attribute mapping between DW user authentication and privilege of dimensional access is illustrated. In our approach, we apply the multi-agent system to automate flexible and effective management of user authentication, role delegation as well as system accountability. Finally, the paper culminates in the prototype system A-COLD (Access Control of web-OLAP over multiple DWs) that incorporates the OLAP features and authentication and authorization enforcement in the multi-user and multi-data warehouse environment.

Geant4 simulation of a 3D high resolution gamma camera

International Nuclear Information System (INIS)

Akhdar, H.; Kezzar, K.; Aksouh, F.; Assemi, N.; AlGhamdi, S.; AlGarawi, M.; Gerl, J.

2015-01-01

The aim of this work is to develop a 3D gamma camera with high position resolution and sensitivity relying on both distance/absorption and Compton scattering techniques and without using any passive collimation. The proposed gamma camera is simulated in order to predict its performance using the full benefit of Geant4 features that allow the construction of the needed geometry of the detectors, have full control of the incident gamma particles and study the response of the detector in order to test the suggested geometries. Three different geometries are simulated and each configuration is tested with three different scintillation materials (LaBr3, LYSO and CeBr3)

Open access web technology for mathematics learning in higher education

Directory of Open Access Journals (Sweden)

Mari Carmen González-Videgaray

2016-05-01

Full Text Available Problems with mathematics learning, “math anxiety” or “statistics anxiety” among university students can be avoided by using teaching strategies and technological tools. Besides personal suffering, low achievement in mathematics reduces terminal efficiency and decreases enrollment in careers related to science, technology and mathematics. This paper has two main goals: 1 to offer an organized inventory of open access web resources for math learning in higher education, and 2 to explore to what extent these resources are currently known and used by students and teachers. The first goal was accomplished by running a search in Google and then classifying resources. For the second, we conducted a survey among a sample of students (n=487 and teachers (n=60 from mathematics and engineering within the largest public university in Mexico. We categorized 15 high-quality web resources. Most of them are interactive simulations and computer algebra systems. ResumenLos problemas en el aprendizaje de las matemáticas, como “ansiedad matemática” y “ansiedad estadística” pueden evitarse si se usan estrategias de enseñanza y herramientas tecnológicas. Además de un sufrimiento personal, el bajo rendimiento en matemáticas reduce la eficiencia terminal y decrementa la matrícula en carreras relacionadas con ciencia, tecnología y matemáticas. Este artículo tiene dos objetivos: 1 ofrecer un inventario organizado de recursos web de acceso abierto para aprender matemáticas en la universidad, y 2 explorar en qué medida estos recursos se usan actualmente entre alumnos y profesores. El primer objetivo se logró con un perfil de búsqueda en Google y una clasificación. Para el segundo, se condujo una encuesta en una muestra de estudiantes (n=487 y maestros (n=60 de matemáticas e ingeniería de la universidad más grande de México. Categorizamos 15 recursos web de alta calidad. La mayoría son simulaciones interactivas y

Operator's guide for VAXGAP, a gamma-ray spectrum analysis package

International Nuclear Information System (INIS)

Killian, E.W.; Femec, D.A.

1992-08-01

This report describes the gamma-ray analysis program VAXGAP, which has continually evolved at the Idaho National Engineering Laboratory over a period of several years. It is an integrated suite of computer programs for performing analyses of pulse-height spectra from high-resolution gamma-ray spectrometers and assorted support functions. VAXGAP programs operate on Digital Equipment Corporation (DEC) VAX computers running the VMS operating system, and were written in VAX FORTRAN and DEC Digital Command Language (DCL). These programs make use of DEC GKS and ReGIS for graphical output on standard terminals and printers, and DEC windows for graphics on workstations and terminals that support the X Window System protocol. This report addresses the use of VAXGAP for data acquisition and control, energy scale calibration, and real-time analyses of background and sample pulse-height spectra. Also addressed are the creation and use efficiency tables and isotope libraries, manipulation of spectrum files and their contents, and graphical display of on-going acquisitions, saved spectra, and mathematical fits to spectral peaks

Galactic x-ray and gamma-ray emission and the nature of the interstellar electron spectrum

Energy Technology Data Exchange (ETDEWEB)

Protheroe, R J; Wolfendale, A W [Durham Univ. (UK). Dept. of Physics

1980-12-01

An analysis is made of all available data, both direct and indirect, on the energy spectrum of cosmic ray electrons. It is shown that the data are consistent with an injection spectrum having a constant exponent, ..gamma.. = 2.1 +- 0.1, over a wide range of energy: 10-10sup(g) MeV. Attention is drawn to the role of a possible deficit of sources in reducing the intensity of local electrons both above 10 GeV and below a few hundred MeV.

The Advanced Gamma-ray Imaging System (AGIS): Simulation Studies

Science.gov (United States)

Fegan, Stephen; Buckley, J. H.; Bugaev, S.; Funk, S.; Konopelko, A.; Maier, G.; Vassiliev, V. V.; Simulation Studies Working Group; AGIS Collaboration

2008-03-01

The Advanced Gamma-ray Imaging System (AGIS) is a concept for the next generation instrument in ground-based very high energy gamma-ray astronomy. It has the goal of achieving significant improvement in sensitivity over current experiments. We present the results of simulation studies of various possible designs for AGIS. The primary characteristics of the array performance, collecting area, angular resolution, background rejection, and sensitivity are discussed.

Spectrum-to-dose conversion operator value function of a Ge(Li) in-situ environmental gamma-ray spectrometer

International Nuclear Information System (INIS)

Terada, Hiromi; Sakai, Eiji; Katagiri, Masaki

1976-05-01

A spectrum-to-dose conversion operator value function was obtained for a 73cm 3 closed-end coaxial Ge(Li) in-situ environmental gamma-ray spectrometer; factors influencing the function are considered. (auth.)

SAMPO 90 - High resolution interactive gamma spectrum analysis including automation with macros

International Nuclear Information System (INIS)

Aarnio, P.A.; Nikkinen, M.T.; Routti, J.T.

1991-01-01

SAMPO 90 is a high performance gamma spectrum analysis program for personal computers. It uses high resolution color graphics to display calibrations, spectra, fitting results as multiplet components, and analysis results. All the analysis phases can be done either under full interactive user control or by using macros for automated measurement and analysis sequences including the control of MCAs and sample changers. Semi-automated calibrations for peak shapes (Gaussian with exponential tails), detector efficiency, and energy are available with a possibility for user intervention through interactive graphics. Accurate peak area determination of even the most complex multiplets, of up to 32 components, is accomplished using linear, non-linear and mixed mode fitting, where the component energies and areas can be either frozen or allowed to float in arbitrary combinations. Nuclide identification is done using associated lines techniques which allow interference correction for fully overlapping peaks. Peaked Background Subtraction can be performed and Minimum Detectable Activities calculated. Attenuation corrections can be taken into account in detector efficiency calculation. The most common PC-based MCA spectrum formats (Canberra S100, Ortec ACE, Nucleus PCA, ND AccuSpec) are supported as well as ASCII spectrum files. A gamma-line library is included together with an editor for user configurable libraries. The analysis reports and program parameters are fully customizable. Function key macros can be used to automate the most common analysis procedures. Small batch type modules are additionally available for routine work. SAMPO 90 is a result of over twenty man years of programming and contains 25,000 lines of Fortran, 10,000 lines of C, and 12,000 lines of assembler

Measurement of the Crab nebula (M1) gamma rays emission spectrum above 1 TeV using the Cerenkov light detection of atmospheric showers

International Nuclear Information System (INIS)

Djannati-Atai, Arache

1995-01-01

One of the major impediments towards reliable measurements in ground-based gamma ray astronomy comes from the lack of a tagged cosmic beam of gamma rays for calibrating the detectors. The main aim of this thesis - done within the framework of the Themistocle experiment - has been to provide a calibration method using the known flux of hadronic cosmic rays as a test beam. After a brief review of the most recent results in gamma ray astronomy and an introduction to the atmospheric Cerenkov technique, we describe the setup of the Themistocle experiment. We then present the calibration method, its performances and the procedures set up for the simulation of the hadronic air showers and the detector. The application of the calibration method to data from almost 400 hours of observation of the Crab nebula will then allow us to give one of the most accurate measurements of its spectrum between 3 and 13 TeV, measurement which is an important step towards the Crab becoming a standard cradle in this energy range. (author) [fr

Spectra of {gamma} rays feeding superdeformed bands

Energy Technology Data Exchange (ETDEWEB)

Lauritsen, T.; Khoo, T.L.; Henry, R.G. [and others

1995-08-01

The spectrum of {gamma}rays coincident with SD transitions contains the transitions which populate the SD band. This spectrum can provide information on the feeding mechanism and on the properties (moment of inertia, collectivity) of excited SD states. We used a model we developed to explain the feeding of SD bands, to calculate the spectrum of feeding {gamma}rays. The Monte Carlo simulations take into account the trigger conditions present in our Eurogam experiment. Both experimental and theoretical spectra contain a statistical component and a broad E2 peak (from transitions occurring between excited states in the SD well). There is good resemblance between the measured and calculated spectra although the calculated multiplicity of an E2 bump is low by {approximately}30%. Work is continuing to improve the quality of the fits, which will result in a better understanding of excited SD states. In addition, a model for the last steps, which cool the {gamma} cascade into the SD yrast line, needs to be developed. A strong M1/E2 low-energy component, which we believe is responsible for this cooling, was observed.

Multiagent -Learning for Aloha-Like Spectrum Access in Cognitive Radio Systems

Directory of Open Access Journals (Sweden)

Li Husheng

2010-01-01

Full Text Available An Aloha-like spectrum access scheme without negotiation is considered for multiuser and multichannel cognitive radio systems. To avoid collisions incurred by the lack of coordination, each secondary user learns how to select channels according to its experience. Multiagent reinforcement leaning (MARL is applied for the secondary users to learn good strategies of channel selection. Specifically, the framework of -learning is extended from single user case to multiagent case by considering other secondary users as a part of the environment. The dynamics of the -learning are illustrated using a Metrick-Polak plot, which shows the traces of -values in the two-user case. For both complete and partial observation cases, rigorous proofs of the convergence of multiagent -learning without communications, under certain conditions, are provided using the Robins-Monro algorithm and contraction mapping, respectively. The learning performance (speed and gain in utility is evaluated by numerical simulations.

J-TEXT WebScope: An efficient data access and visualization system for long pulse fusion experiment

Energy Technology Data Exchange (ETDEWEB)

Zheng, Wei, E-mail: zhenghaku@gmail.com [State Key Laboratory of Advanced Electromagnetic Engineering and Technology in Huazhong University of Science and Technology, Wuhan 430074 (China); School of Electrical and Electronic Engineering in Huazhong University of Science and Technology, Wuhan 430074 (China); Wan, Kuanhong; Chen, Zhi; Hu, Feiran; Liu, Qiang [State Key Laboratory of Advanced Electromagnetic Engineering and Technology in Huazhong University of Science and Technology, Wuhan 430074 (China); School of Electrical and Electronic Engineering in Huazhong University of Science and Technology, Wuhan 430074 (China)

2016-11-15

Highlights: • No matter how large the data is, the response time is always less than 500 milliseconds. • It is intelligent and just gives you the data you want. • It can be accessed directly over the Internet without installing special client software if you already have a browser. • Adopt scale and segment technology to organize data. • To support a new database for the WebScope is quite easy. • With the configuration stored in user’s profile, you have your own portable WebScope. - Abstract: Fusion research is an international collaboration work. To enable researchers across the world to visualize and analyze the experiment data, a web based data access and visualization tool is quite important [1]. Now, a new WebScope based on RIA (Rich Internet Application) is designed and implemented to meet these requirements. On the browser side, a fluent and intuitive interface is provided for researchers at J-TEXT laboratory and collaborators from all over the world to view experiment data and related metadata. The fusion experiments will feature long pulse and high sampling rate in the future. The data access and visualization system in this work has adopted segment and scale concept. Large data samples are re-sampled in different scales and then split into segments for instant response. It allows users to view extremely large data on the web browser efficiently, without worrying about the limitation on the size of the data. The HTML5 and JavaScript based web front-end can provide intuitive and fluent user experience. On the server side, a RESTful (Representational State Transfer) web API, which is based on ASP.NET MVC (Model View Controller), allows users to access the data and its metadata through HTTP (HyperText Transfer Protocol). An interface to the database has been designed to decouple the data access and visualization system from the data storage. It can be applied upon any data storage system like MDSplus or JTEXTDB, and this system is very easy to

J-TEXT WebScope: An efficient data access and visualization system for long pulse fusion experiment

International Nuclear Information System (INIS)

Zheng, Wei; Wan, Kuanhong; Chen, Zhi; Hu, Feiran; Liu, Qiang

2016-01-01

Highlights: • No matter how large the data is, the response time is always less than 500 milliseconds. • It is intelligent and just gives you the data you want. • It can be accessed directly over the Internet without installing special client software if you already have a browser. • Adopt scale and segment technology to organize data. • To support a new database for the WebScope is quite easy. • With the configuration stored in user’s profile, you have your own portable WebScope. - Abstract: Fusion research is an international collaboration work. To enable researchers across the world to visualize and analyze the experiment data, a web based data access and visualization tool is quite important [1]. Now, a new WebScope based on RIA (Rich Internet Application) is designed and implemented to meet these requirements. On the browser side, a fluent and intuitive interface is provided for researchers at J-TEXT laboratory and collaborators from all over the world to view experiment data and related metadata. The fusion experiments will feature long pulse and high sampling rate in the future. The data access and visualization system in this work has adopted segment and scale concept. Large data samples are re-sampled in different scales and then split into segments for instant response. It allows users to view extremely large data on the web browser efficiently, without worrying about the limitation on the size of the data. The HTML5 and JavaScript based web front-end can provide intuitive and fluent user experience. On the server side, a RESTful (Representational State Transfer) web API, which is based on ASP.NET MVC (Model View Controller), allows users to access the data and its metadata through HTTP (HyperText Transfer Protocol). An interface to the database has been designed to decouple the data access and visualization system from the data storage. It can be applied upon any data storage system like MDSplus or JTEXTDB, and this system is very easy to

Study of a Random Navigation on the Web Using Software Simulation

Directory of Open Access Journals (Sweden)

Mirella-Amelia Mioc

2015-12-01

Full Text Available The general information about the World Wide Web are especially nowadays useful in all types of communications. The most used model for simulating the functioning of the web is through the hypergraph. The surfer model was chosen from the known algorithms used for web navigation in this simulation. The main objective of this paper is to analyze the Page Rank and its dependency of Markov Chain Length. In this paper some software implementation are presented and used. The experimental results demonstrate the differences between the Algorithm Page Rank and Experimental Page Rank.

A web-based virtual lighting simulator

Energy Technology Data Exchange (ETDEWEB)

Papamichael, Konstantinos; Lai, Judy; Fuller, Daniel; Tariq, Tara

2002-05-06

This paper is about a web-based ''virtual lighting simulator,'' which is intended to allow architects and lighting designers to quickly assess the effect of key parameters on the daylighting and lighting performance in various space types. The virtual lighting simulator consists of a web-based interface that allows navigation through a large database of images and data, which were generated through parametric lighting simulations. At its current form, the virtual lighting simulator has two main modules, one for daylighting and one for electric lighting. The daylighting module includes images and data for a small office space, varying most key daylighting parameters, such as window size and orientation, glazing type, surface reflectance, sky conditions, time of the year, etc. The electric lighting module includes images and data for five space types (classroom, small office, large open office, warehouse and small retail), varying key lighting parameters, such as the electric lighting system, surface reflectance, dimming/switching, etc. The computed images include perspectives and plans and are displayed in various formats to support qualitative as well as quantitative assessment. The quantitative information is in the form of iso-contour lines superimposed on the images, as well as false color images and statistical information on work plane illuminance. The qualitative information includes images that are adjusted to account for the sensitivity and adaptation of the human eye. The paper also includes a section on the major technical issues and their resolution.

An optical spectrum of the afterglow of a gamma-ray burst at a redshift of z = 6.295.

Science.gov (United States)

Kawai, N; Kosugi, G; Aoki, K; Yamada, T; Totani, T; Ohta, K; Iye, M; Hattori, T; Aoki, W; Furusawa, H; Hurley, K; Kawabata, K S; Kobayashi, N; Komiyama, Y; Mizumoto, Y; Nomoto, K; Noumaru, J; Ogasawara, R; Sato, R; Sekiguchi, K; Shirasaki, Y; Suzuki, M; Takata, T; Tamagawa, T; Terada, H; Watanabe, J; Yatsu, Y; Yoshida, A

2006-03-09

The prompt gamma-ray emission from gamma-ray bursts (GRBs) should be detectable out to distances of z > 10 (ref. 1), and should therefore provide an excellent probe of the evolution of cosmic star formation, reionization of the intergalactic medium, and the metal enrichment history of the Universe. Hitherto, the highest measured redshift for a GRB has been z = 4.50 (ref. 5). Here we report the optical spectrum of the afterglow of GRB 050904 obtained 3.4 days after the burst; the spectrum shows a clear continuum at the long-wavelength end of the spectrum with a sharp cut-off at around 9,000 A due to Lyman alpha absorption at z approximately 6.3 (with a damping wing). A system of absorption lines of heavy elements at z = 6.295 +/- 0.002 was also detected, yielding the precise measurement of the redshift. The Si ii fine-structure lines suggest a dense, metal-enriched environment around the progenitor of the GRB.

Design and Implementation of a Web-based Monitoring System by using EPICS Channel Access Protocol

International Nuclear Information System (INIS)

An, Eun Mi; Song, Yong Gi

2009-01-01

Proton Engineering Frontier Project (PEFP) has developed a 20MeV proton accelerator, and established a distributed control system based on EPICS for sub-system components such as vacuum unit, beam diagnostics, and power supply system. The control system includes a real-time monitoring and alarm functions. From the aspect of a efficient maintenance of a control system and a additional extension of subsystems, EPICS software framework was adopted. In addition, a control system should be capable of providing an easy access for users and a real-time monitoring on a user screen. Therefore, we have implemented a new web-based monitoring server with several libraries. By adding DB module, the new IOC web monitoring system makes it possible to monitor the system through the web. By integrating EPICS Channel Access (CA) and Database libraries into a Database module, the web-based monitoring system makes it possible to monitor the sub-system status through user's internet browser. In this study, we developed a web based monitoring system by using EPICS IOC (Input Output Controller) with IBM server

A University Web Portal redesign applying accessibility patterns. Breaking Down Barriers for Visually Impaired Users

Directory of Open Access Journals (Sweden)

Hernán Sosa

2015-08-01

Full Text Available Definitely, the WWW and ICTs have become the preferred media for the interaction between society and its citizens, and public and private organizations have today the possibility of deploying their activities through the Web. In particular, university education is a domain where the benefits of these technological resources can strongly contribute in caring for students. However, most university Web portals are inaccessible to their user community (students, professors, and non-teaching staff, between others, since these portals do not take into account the needs of people with different capabilities. In this work, we propose an accessibility pattern driven process to the redesign of university Web portals, aiming to break down barriers for visually impaired users. The approach is implemented to a real case study: the Web portal of Universidad Nacional de la Patagonia Austral (UNPA. The results come from applying accessibility recommendations and evaluation tools (automatic and manual from internationally recognized organizations, to both versions of the Web portal: the original and the redesign one.

DIRAC: Secure web user interface

International Nuclear Information System (INIS)

Casajus Ramo, A; Sapunov, M

2010-01-01

Traditionally the interaction between users and the Grid is done with command line tools. However, these tools are difficult to use by non-expert users providing minimal help and generating outputs not always easy to understand especially in case of errors. Graphical User Interfaces are typically limited to providing access to the monitoring or accounting information and concentrate on some particular aspects failing to cover the full spectrum of grid control tasks. To make the Grid more user friendly more complete graphical interfaces are needed. Within the DIRAC project we have attempted to construct a Web based User Interface that provides means not only for monitoring the system behavior but also allows to steer the main user activities on the grid. Using DIRAC's web interface a user can easily track jobs and data. It provides access to job information and allows performing actions on jobs such as killing or deleting. Data managers can define and monitor file transfer activity as well as check requests set by jobs. Production managers can define and follow large data productions and react if necessary by stopping or starting them. The Web Portal is build following all the grid security standards and using modern Web 2.0 technologies which allow to achieve the user experience similar to the desktop applications. Details of the DIRAC Web Portal architecture and User Interface will be presented and discussed.

Calculation Analysis of Calibration Factors of Airborne Gamma-ray Spectrometer

International Nuclear Information System (INIS)

Zhao Jun; Zhu Jinhui; Xie Honggang; He Qinglin

2009-01-01

To determine the calibration factors of an airborne gamma-ray spectrometer measuring large area gamma-ray emitting source at deferent flying height, a series of Monte Carlo simulations were drawn. Response energy spectrums of NaI crystals in airplane caused by nature-decay-series calibration-pads, and calibration factors on different heights above Cs-137 plane source, were obtained. The calculated results agreed with the experimental data well. (authors)

Monte Carlo simulation for the design of industrial gamma-ray transmission tomography

International Nuclear Information System (INIS)

Kim, Jongbum; Jung, Sunghee; Moon, Jinho; Kwon, Taekyong; Cho, Gyuseong

2011-01-01

The Monte Carlo simulation and experiment were carried out for a large-scale industrial gamma ray tomographic scanning geometry. The geometry of the tomographic system has a moving source with 16 stationary detectors. This geometry is advantageous for the diagnosis of a large-scale industrial plant. The simulation data was carried out for the phantom with 32 views, 16 detectors, and a different energy bin. The simulation data was processed to be used for image reconstruction. Image reconstruction was performed by a Diagonally-Scaled Gradient-Ascent algorithm for simulation data. Experiments were conducted in a 78 cm diameter column filled with polypropylene grains. Sixteen 0.5-inch-thick and 1 inch long NaI(Tl) cylindrical detectors, and 20 mCi of 137 Cs radioactive source were used. The experimental results were compared to the simulation data. The experimental results were similar to Monte Carlo simulation results. This result showed that the Monte Carlo simulation is useful for predicting the result of the industrial gamma tomographic scan method And it can also give a solution for designing the industrial gamma tomography system and preparing the field experiment. (author)

Systems and Services for Real-Time Web Access to NPP Data, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Global Science & Technology, Inc. (GST) proposes to investigate information processing and delivery technologies to provide near-real-time Web-based access to...

Database-driven web interface automating gyrokinetic simulations for validation

Science.gov (United States)

Ernst, D. R.

2010-11-01

We are developing a web interface to connect plasma microturbulence simulation codes with experimental data. The website automates the preparation of gyrokinetic simulations utilizing plasma profile and magnetic equilibrium data from TRANSP analysis of experiments, read from MDSPLUS over the internet. This database-driven tool saves user sessions, allowing searches of previous simulations, which can be restored to repeat the same analysis for a new discharge. The website includes a multi-tab, multi-frame, publication quality java plotter Webgraph, developed as part of this project. Input files can be uploaded as templates and edited with context-sensitive help. The website creates inputs for GS2 and GYRO using a well-tested and verified back-end, in use for several years for the GS2 code [D. R. Ernst et al., Phys. Plasmas 11(5) 2637 (2004)]. A centralized web site has the advantage that users receive bug fixes instantaneously, while avoiding the duplicated effort of local compilations. Possible extensions to the database to manage run outputs, toward prototyping for the Fusion Simulation Project, are envisioned. Much of the web development utilized support from the DoE National Undergraduate Fellowship program [e.g., A. Suarez and D. R. Ernst, http://meetings.aps.org/link/BAPS.2005.DPP.GP1.57.

Improving the Aircraft Design Process Using Web-based Modeling and Simulation

Science.gov (United States)

Reed, John A.; Follen, Gregory J.; Afjeh, Abdollah A.

2003-01-01

Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and muitifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation.

Proximal gamma-ray spectroscopy to predict soil properties using windows and full-spectrum analysis methods.

Science.gov (United States)

Mahmood, Hafiz Sultan; Hoogmoed, Willem B; van Henten, Eldert J

2013-11-27

Fine-scale spatial information on soil properties is needed to successfully implement precision agriculture. Proximal gamma-ray spectroscopy has recently emerged as a promising tool to collect fine-scale soil information. The objective of this study was to evaluate a proximal gamma-ray spectrometer to predict several soil properties using energy-windows and full-spectrum analysis methods in two differently managed sandy loam fields: conventional and organic. In the conventional field, both methods predicted clay, pH and total nitrogen with a good accuracy (R2 ≥ 0.56) in the top 0-15 cm soil depth, whereas in the organic field, only clay content was predicted with such accuracy. The highest prediction accuracy was found for total nitrogen (R2 = 0.75) in the conventional field in the energy-windows method. Predictions were better in the top 0-15 cm soil depths than in the 15-30 cm soil depths for individual and combined fields. This implies that gamma-ray spectroscopy can generally benefit soil characterisation for annual crops where the condition of the seedbed is important. Small differences in soil structure (conventional vs. organic) cannot be determined. As for the methodology, we conclude that the energy-windows method can establish relations between radionuclide data and soil properties as accurate as the full-spectrum analysis method.

Websim3d: A Web-based System for Generation, Storage and Dissemination of Earthquake Ground Motion Simulations.

Science.gov (United States)

Olsen, K. B.

2003-12-01

Synthetic time histories from large-scale 3D ground motion simulations generally constitute large 'data' sets which typically require 100's of Mbytes or Gbytes of storage capacity. For the same reason, getting access to a researchers simulation output, for example for an earthquake engineer to perform site analysis, or a seismologist to perform seismic hazard analysis, can be a tedious procedure. To circumvent this problem we have developed a web-based ``community model'' (websim3D) for the generation, storage, and dissemination of ground motion simulation results. Websim3D allows user-friendly and fast access to view and download such simulation results for an earthquake-prone area. The user selects an earthquake scenario from a map of the region, which brings up a map of the area where simulation data is available. Now, by clicking on an arbitrary site location, synthetic seismograms and/or soil parameters for the site can be displayed at fixed or variable scaling and/or downloaded. Websim3D relies on PHP scripts for the dynamic plots of synthetic seismograms and soil profiles. Although not limited to a specific area, we illustrate the community model for simulation results from the Los Angeles basin, Wellington (New Zealand), and Mexico.

A Novel Approach for Transmission of 56 Gbit/s NRZ Signal in Access Network Using Spectrum Slicing Technique

DEFF Research Database (Denmark)

Spolitis, S.; Vegas Olmos, Juan José; Bobrovs, V.

2013-01-01

We present the spectrum slicing and stitching concept for high-capacity low optics complexity optical access networks. Spectrum slicing and stitching of a 56 Gbit/s NRZ electrical signal is experimentally demonstrated for the first time.......We present the spectrum slicing and stitching concept for high-capacity low optics complexity optical access networks. Spectrum slicing and stitching of a 56 Gbit/s NRZ electrical signal is experimentally demonstrated for the first time....

Using ant-behavior-based simulation model AntWeb to improve website organization

Science.gov (United States)

Li, Weigang; Pinheiro Dib, Marcos V.; Teles, Wesley M.; Morais de Andrade, Vlaudemir; Alves de Melo, Alba C. M.; Cariolano, Judas T.

2002-03-01

Some web usage mining algorithms showed the potential application to find the difference among the organizations expected by visitors to the website. However, there are still no efficient method and criterion for a web administrator to measure the performance of the modification. In this paper, we developed an AntWeb, a model inspired by ants' behavior to simulate the sequence of visiting the website, in order to measure the efficient of the web structure. We implemented a web usage mining algorithm using backtrack to the intranet website of the Politec Informatic Ltd., Brazil. We defined throughput (the number of visitors to reach their target pages per time unit relates to the total number of visitors) as an index to measure the website's performance. We also used the link in a web page to represent the effect of visitors' pheromone trails. For every modification in the website organization, for example, putting a link from the expected location to the target object, the simulation reported the value of throughput as a quick answer about this modification. The experiment showed the stability of our simulation model, and a positive modification to the intranet website of the Politec.

Interactive Web-based Floodplain Simulation System for Realistic Experiments of Flooding and Flood Damage

Science.gov (United States)

Demir, I.

2013-12-01

Recent developments in web technologies make it easy to manage and visualize large data sets with general public. Novel visualization techniques and dynamic user interfaces allow users to create realistic environments, and interact with data to gain insight from simulations and environmental observations. The floodplain simulation system is a web-based 3D interactive flood simulation environment to create real world flooding scenarios. The simulation systems provides a visually striking platform with realistic terrain information, and water simulation. Students can create and modify predefined scenarios, control environmental parameters, and evaluate flood mitigation techniques. The web-based simulation system provides an environment to children and adults learn about the flooding, flood damage, and effects of development and human activity in the floodplain. The system provides various scenarios customized to fit the age and education level of the users. This presentation provides an overview of the web-based flood simulation system, and demonstrates the capabilities of the system for various flooding and land use scenarios.

The Advanced Gamma-ray Imaging System (AGIS): Simulation Studies

OpenAIRE

Maier, G.; Collaboration, for the AGIS

2009-01-01

The Advanced Gamma-ray Imaging System (AGIS) is a next-generation ground-based gamma-ray observatory being planned in the U.S. The anticipated sensitivity of AGIS is about one order of magnitude better than the sensitivity of current observatories, allowing it to measure gammaray emmission from a large number of Galactic and extra-galactic sources. We present here results of simulation studies of various possible designs for AGIS. The primary characteristics of the array performance - collect...

Novel Web-based Education Platforms for Information Communication utilizing Gamification, Virtual and Immersive Reality

Science.gov (United States)

Demir, I.

2015-12-01

Recent developments in internet technologies make it possible to manage and visualize large data on the web. Novel visualization techniques and interactive user interfaces allow users to create realistic environments, and interact with data to gain insight from simulations and environmental observations. This presentation showcase information communication interfaces, games, and virtual and immersive reality applications for supporting teaching and learning of concepts in atmospheric and hydrological sciences. The information communication platforms utilizes latest web technologies and allow accessing and visualizing large scale data on the web. The simulation system is a web-based 3D interactive learning environment for teaching hydrological and atmospheric processes and concepts. The simulation systems provides a visually striking platform with realistic terrain and weather information, and water simulation. The web-based simulation system provides an environment for students to learn about the earth science processes, and effects of development and human activity on the terrain. Users can access the system in three visualization modes including virtual reality, augmented reality, and immersive reality using heads-up display. The system provides various scenarios customized to fit the age and education level of various users.

A 3D simulation look-up library for real-time airborne gamma-ray spectroscopy

Science.gov (United States)

Kulisek, Jonathan A.; Wittman, Richard S.; Miller, Erin A.; Kernan, Warnick J.; McCall, Jonathon D.; McConn, Ron J.; Schweppe, John E.; Seifert, Carolyn E.; Stave, Sean C.; Stewart, Trevor N.

2018-01-01

A three-dimensional look-up library consisting of simulated gamma-ray spectra was developed to leverage, in real-time, the abundance of data provided by a helicopter-mounted gamma-ray detection system consisting of 92 CsI-based radiation sensors and exhibiting a highly angular-dependent response. We have demonstrated how this library can be used to help effectively estimate the terrestrial gamma-ray background, develop simulated flight scenarios, and to localize radiological sources. Source localization accuracy was significantly improved, particularly for weak sources, by estimating the entire gamma-ray spectra while accounting for scattering in the air, and especially off the ground.

Investigation of the 800 keV Peak in the Gamma Spectrum of Swedish Laplanders

Energy Technology Data Exchange (ETDEWEB)

Andersson, I Oe; Nilsson, I; Eckerstig, K

1962-08-15

The gamma spectrum of the body radioactivity in reindeer raising Laplanders has shown a peak at 800 keV, which has not been discussed before in connection with whole body counting. We present here an investigation that was made to be able to identify the isotope. The result is that the peak comes from cesium 134. The possibility to find cesium 134 in fallout is discussed.

Investigation of the 800 keV Peak in the Gamma Spectrum of Swedish Laplanders

International Nuclear Information System (INIS)

Andersson, I.Oe.; Nilsson, I.; Eckerstig, K.

1962-08-01

The gamma spectrum of the body radioactivity in reindeer raising Laplanders has shown a peak at 800 keV, which has not been discussed before in connection with whole body counting. We present here an investigation that was made to be able to identify the isotope. The result is that the peak comes from cesium 134. The possibility to find cesium 134 in fallout is discussed

Examination of models of knee in primary cosmic ray spectrum using gamma-hadron families

International Nuclear Information System (INIS)

Sveshnikova, L.G.; Managadze, A.K.; Roganova, T.M.; Mukhamedshin, R.A.

2005-01-01

Four models for describing the primary cosmic radiation (PCR) spectrum are proposed/ The examination of the PCR spectra models is carried out from the viewpoint of their consistency with the data on the gamma-hadron families for the threshold energies of 100 and 500 TeV. The maximum possible contribution of the superfamilies, originating from the primary nuclei, but not from the protons, is calculated [ru

Development of LabVIEW web-based simulator for RELAP5

Energy Technology Data Exchange (ETDEWEB)

Macedo, Luiz A.; Torres, Walmir M.; Sabundjian, Gaiane; Andrade, Delvonei A.; Belchior Junior, Antonio; Umbehaun, Pedro E.; Conti, Thadeu N.; Mesquita, Roberto N. de; Masotti, Paulo H.F.; Angelo, Gabriel, E-mail: lamacedo@ipen.b, E-mail: wmtorres@ipen.b, E-mail: gdjian@ipen.b, E-mail: delvonei@ipen.b, E-mail: abelchior@ipen.b, E-mail: umbehaun@ipen.b, E-mail: tnconti@ipen.b, E-mail: rnavarro@ipen.b, E-mail: , E-mail: masotti@ipen.b, E-mail: gabriel.angelo@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

This work presents the development of a LabVIEW web-based simulator using the output results of the best estimate nuclear system analysis code, RELAP5, for graphical user interfaces and web-casting. A numerical based model designed for natural circulation studies on the thermal hydraulic experimental facility called Natural Circulation Circuit, was developed with RELAP5 code. Specific output results from RELAP5 simulation are displayed in a user friendly graphical format. The temperatures are shown as a function of time in a XY graphic. Temperatures, levels and void fractions are displayed in color-coded scale which change in time on the graphical interface representing the circuit. An alarm is set for the case of onset boiling temperature occurrence at the heater outlet. This simulator allows an easy visual understanding of the thermal hydraulic circuit behavior. It can be shared, via Web, with researchers in any geographical location and, at the same time, it can be used in learning for distance educational purposes. In future work, this LabVIEW simulator will be coupled with RELAP5 code through dll's. Simultaneous graphical displaying and code calculations will be possible. Results are presented and discussed. (author)

Development of LabVIEW web-based simulator for RELAP5

International Nuclear Information System (INIS)

Macedo, Luiz A.; Torres, Walmir M.; Sabundjian, Gaiane; Andrade, Delvonei A.; Belchior Junior, Antonio; Umbehaun, Pedro E.; Conti, Thadeu N.; Mesquita, Roberto N. de; Masotti, Paulo H.F.; Angelo, Gabriel

2011-01-01

This work presents the development of a LabVIEW web-based simulator using the output results of the best estimate nuclear system analysis code, RELAP5, for graphical user interfaces and web-casting. A numerical based model designed for natural circulation studies on the thermal hydraulic experimental facility called Natural Circulation Circuit, was developed with RELAP5 code. Specific output results from RELAP5 simulation are displayed in a user friendly graphical format. The temperatures are shown as a function of time in a XY graphic. Temperatures, levels and void fractions are displayed in color-coded scale which change in time on the graphical interface representing the circuit. An alarm is set for the case of onset boiling temperature occurrence at the heater outlet. This simulator allows an easy visual understanding of the thermal hydraulic circuit behavior. It can be shared, via Web, with researchers in any geographical location and, at the same time, it can be used in learning for distance educational purposes. In future work, this LabVIEW simulator will be coupled with RELAP5 code through dll's. Simultaneous graphical displaying and code calculations will be possible. Results are presented and discussed. (author)

Web Accessibility of the Higher Education Institute Websites Based on the World Wide Web Consortium and Section 508 of the Rehabilitation Act

Science.gov (United States)

Alam, Najma H.

2014-01-01

The problem observed in this study is the low level of compliance of higher education website accessibility with Section 508 of the Rehabilitation Act of 1973. The literature supports the non-compliance of websites with the federal policy in general. Studies were performed to analyze the accessibility of fifty-four sample web pages using automated…

Chapter 18: Web-based Tools - NED VO Services

Science.gov (United States)

Mazzarella, J. M.; NED Team

The NASA/IPAC Extragalactic Database (NED) is a thematic, web-based research facility in widespread use by scientists, educators, space missions, and observatory operations for observation planning, data analysis, discovery, and publication of research about objects beyond our Milky Way galaxy. NED is a portal into a systematic fusion of data from hundreds of sky surveys and tens of thousands of research publications. The contents and services span the entire electromagnetic spectrum from gamma rays through radio frequencies, and are continuously updated to reflect the current literature and releases of large-scale sky survey catalogs. NED has been on the Internet since 1990, growing in content, automation and services with the evolution of information technology. NED is the world's largest database of crossidentified extragalactic objects. As of December 2006, the system contains approximately 10 million objects and 15 million multi-wavelength cross-IDs. Over 4 thousand catalogs and published lists covering the entire electromagnetic spectrum have had their objects cross-identified or associated, with fundamental data parameters federated for convenient queries and retrieval. This chapter describes the interoperability of NED services with other components of the Virtual Observatory (VO). Section 1 is a brief overview of the primary NED web services. Section 2 provides a tutorial for using NED services currently available through the NVO Registry. The "name resolver" provides VO portals and related internet services with celestial coordinates for objects specified by catalog identifier (name); any alias can be queried because this service is based on the source cross-IDs established by NED. All major services have been updated to provide output in VOTable (XML) format that can be accessed directly from the NED web interface or using the NVO registry. These include access to images via SIAP, Cone- Search queries, and services providing fundamental, multi

U-Access: a web-based system for routing pedestrians of differing abilities

Science.gov (United States)

Sobek, Adam D.; Miller, Harvey J.

2006-09-01

For most people, traveling through urban and built environments is straightforward. However, for people with physical disabilities, even a short trip can be difficult and perhaps impossible. This paper provides the design and implementation of a web-based system for the routing and prescriptive analysis of pedestrians with different physical abilities within built environments. U-Access, as a routing tool, provides pedestrians with the shortest feasible route with respect to one of three differing ability levels, namely, peripatetic (unaided mobility), aided mobility (mobility with the help of a cane, walker or crutches) and wheelchair users. U-Access is also an analytical tool that can help identify obstacles in built environments that create routing discrepancies among pedestrians with different physical abilities. This paper discusses the system design, including database, algorithm and interface specifications, and technologies for efficiently delivering results through the World Wide Web (WWW). This paper also provides an illustrative example of a routing problem and an analytical evaluation of the existing infrastructure which identifies the obstacles that pose the greatest discrepancies between physical ability levels. U-Access was evaluated by wheelchair users and route experts from the Center for Disability Services at The University of Utah, USA.

A Web Services Data Analysis Grid

Energy Technology Data Exchange (ETDEWEB)

William A Watson III; Ian Bird; Jie Chen; Bryan Hess; Andy Kowalski; Ying Chen

2002-07-01

The trend in large-scale scientific data analysis is to exploit compute, storage and other resources located at multiple sites, and to make those resources accessible to the scientist as if they were a single, coherent system. Web technologies driven by the huge and rapidly growing electronic commerce industry provide valuable components to speed the deployment of such sophisticated systems. Jefferson Lab, where several hundred terabytes of experimental data are acquired each year, is in the process of developing a web-based distributed system for data analysis and management. The essential aspects of this system are a distributed data grid (site independent access to experiment, simulation and model data) and a distributed batch system, augmented with various supervisory and management capabilities, and integrated using Java and XML-based web services.

A Web Services Data Analysis Grid

International Nuclear Information System (INIS)

William A Watson III; Ian Bird; Jie Chen; Bryan Hess; Andy Kowalski; Ying Chen

2002-01-01

The trend in large-scale scientific data analysis is to exploit compute, storage and other resources located at multiple sites, and to make those resources accessible to the scientist as if they were a single, coherent system. Web technologies driven by the huge and rapidly growing electronic commerce industry provide valuable components to speed the deployment of such sophisticated systems. Jefferson Lab, where several hundred terabytes of experimental data are acquired each year, is in the process of developing a web-based distributed system for data analysis and management. The essential aspects of this system are a distributed data grid (site independent access to experiment, simulation and model data) and a distributed batch system, augmented with various supervisory and management capabilities, and integrated using Java and XML-based web services

Comparison of penumbra regions produced by ancient Gamma knife model C and Gamma ART 6000 using Monte Carlo MCNP6 simulation.

Science.gov (United States)

Banaee, Nooshin; Asgari, Sepideh; Nedaie, Hassan Ali

2018-07-01

The accuracy of penumbral measurements in radiotherapy is pivotal because dose planning computers require accurate data to adequately modeling the beams, which in turn are used to calculate patient dose distributions. Gamma knife is a non-invasive intracranial technique based on principles of the Leksell stereotactic system for open deep brain surgeries, invented and developed by Professor Lars Leksell. The aim of this study is to compare the penumbra widths of Leksell Gamma Knife model C and Gamma ART 6000. Initially, the structure of both systems were simulated by using Monte Carlo MCNP6 code and after validating the accuracy of simulation, beam profiles of different collimators were plotted. MCNP6 beam profile calculations showed that the penumbra values of Leksell Gamma knife model C and Gamma ART 6000 for 18, 14, 8 and 4 mm collimators are 9.7, 7.9, 4.3, 2.6 and 8.2, 6.9, 3.6, 2.4, respectively. The results of this study showed that since Gamma ART 6000 has larger solid angle in comparison with Gamma Knife model C, it produces better beam profile penumbras than Gamma Knife model C in the direct plane. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Advanced Gamma-ray Imaging System (AGIS)-Simulation Studies

Science.gov (United States)

Maier, G.; Buckley, J.; Bugaev, V.; Fegan, S.; Funk, S.; Konopelko, A.; Vassiliev, V. V.

2008-12-01

The Advanced Gamma-ray Imaging System (AGIS) is a US-led concept for a next-generation instrument in ground-based very-high-energy gamma-ray astronomy. The most important design requirement for AGIS is a sensitivity of about 10 times greater than current observatories like Veritas, H.E.S.S or MAGIC. We present results of simulation studies of various possible designs for AGIS. The primary characteristics of the array performance, collecting area, angular resolution, background rejection, and sensitivity are discussed.

Food web framework for size-structured populations

DEFF Research Database (Denmark)

Hartvig, Martin; Andersen, Ken Haste; Beyer, Jan

2011-01-01

. Parameter values are determined from cross-species analysis of fish communities as life-history omnivory is widespread in aquatic systems, but may be reparameterised for other systems. An ensemble of food webs is generated and the resulting communities are analysed at four levels of organisation: community......We synthesise traditional unstructured food webs, allometric body size scaling, trait-based modelling, and physiologically structured modelling to provide a novel and ecologically relevant tool for size-structured food webs. The framework allows food web models to include ontogenetic growth...... level, species level, trait level, and individual level. The model may be solved analytically by assuming that the community spectrum follows a power law. The analytical solution provides a baseline expectation of the results of complex food web simulations, and agrees well with the predictions...

Temporal Evolution of the Gamma-ray Burst Afterglow Spectrum for an Observer: GeV–TeV Synchrotron Self-Compton Light Curve

Energy Technology Data Exchange (ETDEWEB)

Fukushima, Takuma; Fujita, Yutaka [Department of Earth and Space Science, Osaka University, Osaka, 560-0043 (Japan); To, Sho; Asano, Katsuaki, E-mail: fukushima@vega.ess.sci.osaka-u.ac.jp, E-mail: fujita@vega.ess.sci.osaka-u.ac.jp, E-mail: tosho@icrr.u-tokyo.ac.jp, E-mail: asanok@icrr.u-tokyo.ac.jp [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan)

2017-08-01

We numerically simulate the gamma-ray burst (GRB) afterglow emission with a one-zone time-dependent code. The temporal evolutions of the decelerating shocked shell and energy distributions of electrons and photons are consistently calculated. The photon spectrum and light curves for an observer are obtained taking into account the relativistic propagation of the shocked shell and the curvature of the emission surface. We find that the onset time of the afterglow is significantly earlier than the previous analytical estimate. The analytical formulae of the shock propagation and light curve for the radiative case are also different from our results. Our results show that even if the emission mechanism is switching from synchrotron to synchrotron self-Compton, the gamma-ray light curves can be a smooth power law, which agrees with the observed light curve and the late detection of a 32 GeV photon in GRB 130427A. The uncertainty of the model parameters obtained with the analytical formula is discussed, especially in connection with the closure relation between spectral index and decay index.

The Osseus platform: a prototype for advanced web-based distributed simulation

Science.gov (United States)

Franceschini, Derrick; Riecken, Mark

2016-05-01

Recent technological advances in web-based distributed computing and database technology have made possible a deeper and more transparent integration of some modeling and simulation applications. Despite these advances towards true integration of capabilities, disparate systems, architectures, and protocols will remain in the inventory for some time to come. These disparities present interoperability challenges for distributed modeling and simulation whether the application is training, experimentation, or analysis. Traditional approaches call for building gateways to bridge between disparate protocols and retaining interoperability specialists. Challenges in reconciling data models also persist. These challenges and their traditional mitigation approaches directly contribute to higher costs, schedule delays, and frustration for the end users. Osseus is a prototype software platform originally funded as a research project by the Defense Modeling & Simulation Coordination Office (DMSCO) to examine interoperability alternatives using modern, web-based technology and taking inspiration from the commercial sector. Osseus provides tools and services for nonexpert users to connect simulations, targeting the time and skillset needed to successfully connect disparate systems. The Osseus platform presents a web services interface to allow simulation applications to exchange data using modern techniques efficiently over Local or Wide Area Networks. Further, it provides Service Oriented Architecture capabilities such that finer granularity components such as individual models can contribute to simulation with minimal effort.

The quality and accessibility of Australian depression sites on the World Wide Web.

Science.gov (United States)

Griffiths, Kathleen M; Christensen, Helen

2002-05-20

To provide information about Australian depression sites and the quality of their content; to identify possible indicators of the quality of site content; and determine the accessibility of Australian depression web sites. Cross-sectional survey of 15 Australian depression web sites. (i) Quality of treatment content (concordance of site information with evidence-based guidelines, number of evidence-based treatments recommended, discussion of other relevant issues, subjective rating of treatment content); (ii) potential quality indicators (conformity with DISCERN criteria, citation of scientific evidence); (iii) accessibility (search engine rank). Mean content quality scores were not high and site accessibility was poor. There was a consistent association between the quality-of-content measures and the DISCERN and scientific accountability scores. Search engine rank was not associated with content quality. The quality of information about depression on Australian websites could be improved. DISCERN may be a useful indicator of website quality, as may scientific accountability. The sites that received the highest quality-of-content ratings were beyondblue, BluePages, CRUfAD and InfraPsych.

ChEMBL web services: streamlining access to drug discovery data and utilities.

Science.gov (United States)

Davies, Mark; Nowotka, Michał; Papadatos, George; Dedman, Nathan; Gaulton, Anna; Atkinson, Francis; Bellis, Louisa; Overington, John P

2015-07-01

ChEMBL is now a well-established resource in the fields of drug discovery and medicinal chemistry research. The ChEMBL database curates and stores standardized bioactivity, molecule, target and drug data extracted from multiple sources, including the primary medicinal chemistry literature. Programmatic access to ChEMBL data has been improved by a recent update to the ChEMBL web services (version 2.0.x, https://www.ebi.ac.uk/chembl/api/data/docs), which exposes significantly more data from the underlying database and introduces new functionality. To complement the data-focused services, a utility service (version 1.0.x, https://www.ebi.ac.uk/chembl/api/utils/docs), which provides RESTful access to commonly used cheminformatics methods, has also been concurrently developed. The ChEMBL web services can be used together or independently to build applications and data processing workflows relevant to drug discovery and chemical biology. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

THE DETECTABILITY OF DARK MATTER ANNIHILATION WITH FERMI USING THE ANISOTROPY ENERGY SPECTRUM OF THE GAMMA-RAY BACKGROUND

International Nuclear Information System (INIS)

Hensley, Brandon S.; Pavlidou, Vasiliki; Siegal-Gaskins, Jennifer M.

2010-01-01

The energy dependence of the anisotropy (the anisotropy energy spectrum) of the large-scale diffuse gamma-ray background can reveal the presence of multiple source populations. Annihilating dark matter in the substructure of the Milky Way halo could give rise to a modulation in the anisotropy energy spectrum of the diffuse gamma-ray emission measured by Fermi, enabling the detection of a dark matter signal. We determine the detectability of a dark-matter-induced modulation for scenarios in which unresolved blazars are the primary contributor to the measured emission above ∼1 GeV and find that in some scenarios pair-annihilation cross sections on the order of the value expected for thermal relic dark matter can produce a detectable feature. We anticipate that the sensitivity of this technique to specific dark matter models could be improved by tailored likelihood analysis methods.

A trial of e-simulation of sudden patient deterioration (FIRST2ACT WEB) on student learning.

Science.gov (United States)

Bogossian, Fiona E; Cooper, Simon J; Cant, Robyn; Porter, Joanne; Forbes, Helen

2015-10-01

High-fidelity simulation pedagogy is of increasing importance in health professional education; however, face-to-face simulation programs are resource intensive and impractical to implement across large numbers of students. To investigate undergraduate nursing students' theoretical and applied learning in response to the e-simulation program-FIRST2ACT WEBTM, and explore predictors of virtual clinical performance. Multi-center trial of FIRST2ACT WEBTM accessible to students in five Australian universities and colleges, across 8 campuses. A population of 489 final-year nursing students in programs of study leading to license to practice. Participants proceeded through three phases: (i) pre-simulation-briefing and assessment of clinical knowledge and experience; (ii) e-simulation-three interactive e-simulation clinical scenarios which included video recordings of patients with deteriorating conditions, interactive clinical tasks, pop up responses to tasks, and timed performance; and (iii) post-simulation feedback and evaluation. Descriptive statistics were followed by bivariate analysis to detect any associations, which were further tested using standard regression analysis. Of 409 students who commenced the program (83% response rate), 367 undergraduate nursing students completed the web-based program in its entirety, yielding a completion rate of 89.7%; 38.1% of students achieved passing clinical performance across three scenarios, and the proportion achieving passing clinical knowledge increased from 78.15% pre-simulation to 91.6% post-simulation. Knowledge was the main independent predictor of clinical performance in responding to a virtual deteriorating patient R(2)=0.090, F(7, 352)=4.962, plearning. The web-based e-simulation program FIRST2ACTTM effectively enhanced knowledge, virtual clinical performance, and self-assessed knowledge, skills, confidence, and competence in final-year nursing students. Copyright © 2015 Elsevier Ltd. All rights reserved.

Constraining Gamma-Ray Pulsar Gap Models with a Simulated Pulsar Population

Science.gov (United States)

Pierbattista, Marco; Grenier, I. A.; Harding, A. K.; Gonthier, P. L.

2012-01-01

With the large sample of young gamma-ray pulsars discovered by the Fermi Large Area Telescope (LAT), population synthesis has become a powerful tool for comparing their collective properties with model predictions. We synthesised a pulsar population based on a radio emission model and four gamma-ray gap models (Polar Cap, Slot Gap, Outer Gap, and One Pole Caustic). Applying gamma-ray and radio visibility criteria, we normalise the simulation to the number of detected radio pulsars by a select group of ten radio surveys. The luminosity and the wide beams from the outer gaps can easily account for the number of Fermi detections in 2 years of observations. The wide slot-gap beam requires an increase by a factor of 10 of the predicted luminosity to produce a reasonable number of gamma-ray pulsars. Such large increases in the luminosity may be accommodated by implementing offset polar caps. The narrow polar-cap beams contribute at most only a handful of LAT pulsars. Using standard distributions in birth location and pulsar spin-down power (E), we skew the initial magnetic field and period distributions in a an attempt to account for the high E Fermi pulsars. While we compromise the agreement between simulated and detected distributions of radio pulsars, the simulations fail to reproduce the LAT findings: all models under-predict the number of LAT pulsars with high E , and they cannot explain the high probability of detecting both the radio and gamma-ray beams at high E. The beaming factor remains close to 1.0 over 4 decades in E evolution for the slot gap whereas it significantly decreases with increasing age for the outer gaps. The evolution of the enhanced slot-gap luminosity with E is compatible with the large dispersion of gamma-ray luminosity seen in the LAT data. The stronger evolution predicted for the outer gap, which is linked to the polar cap heating by the return current, is apparently not supported by the LAT data. The LAT sample of gamma-ray pulsars

A web-based, collaborative modeling, simulation, and parallel computing environment for electromechanical systems

Directory of Open Access Journals (Sweden)

Xiaoliang Yin

2015-03-01

Full Text Available Complex electromechanical system is usually composed of multiple components from different domains, including mechanical, electronic, hydraulic, control, and so on. Modeling and simulation for electromechanical system on a unified platform is one of the research hotspots in system engineering at present. It is also the development trend of the design for complex electromechanical system. The unified modeling techniques and tools based on Modelica language provide a satisfactory solution. To meet with the requirements of collaborative modeling, simulation, and parallel computing for complex electromechanical systems based on Modelica, a general web-based modeling and simulation prototype environment, namely, WebMWorks, is designed and implemented. Based on the rich Internet application technologies, an interactive graphic user interface for modeling and post-processing on web browser was implemented; with the collaborative design module, the environment supports top-down, concurrent modeling and team cooperation; additionally, service-oriented architecture–based architecture was applied to supply compiling and solving services which run on cloud-like servers, so the environment can manage and dispatch large-scale simulation tasks in parallel on multiple computing servers simultaneously. An engineering application about pure electric vehicle is tested on WebMWorks. The results of simulation and parametric experiment demonstrate that the tested web-based environment can effectively shorten the design cycle of the complex electromechanical system.

Sign Language Translation in State Administration in Germany: Barrier Free Web Accessibility

OpenAIRE

Lišková, Kateřina

2014-01-01

The aim of this thesis is to describe Web accessibility in state administration in the Federal Republic of Germany in relation to the socio-demographic group of deaf sign language users who did not have the opportunity to gain proper knowledge of a written form of the German language. The demand of the Deaf to information in an accessible form as based on legal documents is presented in relation to the theory of translation. How translating from written texts into sign language works in pract...

Making It Work for Everyone: HTML5 and CSS Level 3 for Responsive, Accessible Design on Your Library's Web Site

Science.gov (United States)

Baker, Stewart C.

2014-01-01

This article argues that accessibility and universality are essential to good Web design. A brief review of library science literature sets the issue of Web accessibility in context. The bulk of the article explains the design philosophies of progressive enhancement and responsive Web design, and summarizes recent updates to WCAG 2.0, HTML5, CSS…

Guide on Project Web Access of SFR R and D and Technology Monitoring System

International Nuclear Information System (INIS)

Lee, Dong Uk; Won, Byung Chool; Lee, Yong Bum; Kim, Young In; Hahn, Do Hee

2008-09-01

The SFR R and D and technology monitoring system based on the MS enterprise project management is developed for systematic effective management of 'Development of Basic Key Technologies for Gen IV SFR' project which was performed under the Mid- and Long-term Nuclear R and D Program sponsored by the Ministry of Education, Science and Technology. This system is a tool for project management based on web access. Therefore this manual is a detailed guide for Project Web Access(PWA). Section 1 describes the common guide for using of system functions such as project server 2007 client connection setting, additional outlook function setting etc. The section 2 describes the guide for system administrator. It is described the guide for project management in section 3, 4

Guide on Project Web Access of SFR R and D and Technology Monitoring System

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Uk; Won, Byung Chool; Lee, Yong Bum; Kim, Young In; Hahn, Do Hee

2008-09-15

The SFR R and D and technology monitoring system based on the MS enterprise project management is developed for systematic effective management of 'Development of Basic Key Technologies for Gen IV SFR' project which was performed under the Mid- and Long-term Nuclear R and D Program sponsored by the Ministry of Education, Science and Technology. This system is a tool for project management based on web access. Therefore this manual is a detailed guide for Project Web Access(PWA). Section 1 describes the common guide for using of system functions such as project server 2007 client connection setting, additional outlook function setting etc. The section 2 describes the guide for system administrator. It is described the guide for project management in section 3, 4.

Video game access, parental rules, and problem behavior: a study of boys with autism spectrum disorder.

Science.gov (United States)

Engelhardt, Christopher R; Mazurek, Micah O

2014-07-01

Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to 18 years of age). Parents of these children reported on (1) whether they had specific rules regulating their child's video game use, (2) whether their child had in-room access to a variety of screen-based media devices (television, computer, and video game console), and (3) their child's oppositional behaviors. Multivariate regression models showed that in-room access to a video game console predicted oppositional behavior while controlling for in-room access to other media devices (computer and television) and relevant variables (e.g. average number of video game hours played per day). Additionally, the association between in-room access to a video game console and oppositional behavior was particularly large when parents reported no rules on their child's video game use. The current findings indicate that both access and parental rules regarding video games warrant future experimental and longitudinal research as they relate to problem behavior in boys with autism spectrum disorder. © The Author(s) 2013.

Theoretical determination of spectrum-exposure rate conversion operator of HPGe detector and its application to the measurement of environmental gamma-ray exposure rate

International Nuclear Information System (INIS)

Park, Ch.M.; Choi, B.I.; Kwak, S.S.; Ji, P.K.; Kim, T.W.; Park, Y.W.; Yoon, B.K.

1993-01-01

A conversion operator between spectrum and exposure rate, using a portable HPGe detector for environmental radiation monitoring, was determined theoretically under the assumption of uniform distribution of radiation source on the ground surface. The measurement results were compared with those of a pressurized ionization chamber. The results obtained with the HPGe detector were slightly lower. The method can be easily applied to any gamma ray detector to obtain a spectrum - exposure-rate conversion factor for computing the exposure rate of environmental gamma radiation. (N.T.) 15 refs.; 6 figs.; 3 tabs

Design and Implementation of File Access and Control System Based on Dynamic Web

Institute of Scientific and Technical Information of China (English)

GAO Fuxiang; YAO Lan; BAO Shengfei; YU Ge

2006-01-01

A dynamic Web application, which can help the departments of enterprise to collaborate with each other conveniently, is proposed. Several popular design solutions are introduced at first. Then, dynamic Web system is chosen for developing the file access and control system. Finally, the paper gives the detailed process of the design and implementation of the system, which includes some key problems such as solutions of document management and system security. Additionally, the limitations of the system as well as the suggestions of further improvement are also explained.

Web-based multimedia courseware for emergency cardiac patient management simulations.

Science.gov (United States)

Ambrosiadou, V; Compton, T; Panchal, T; Polovina, S

2000-01-01

This is a multidisciplinary inter-departmental/faculty project between the departments of computer science, electronic, communications and electrical engineering and nursing and paramedic sciences. The objective is to develop a web based multimedia front end to existing simulations of cardiac emergency scenaria. It will be used firstly in the teaching of nurses. The University of Hertfordshire is the only University in Britain using simulations of cardiac emergency scenaria for nurse and paramedic science education and therefore this project will add the multimedia dimension in distributed courses over the web and will assess the improvement in the educational process. The use of network and multimedia technologies, provide interactive learning, immediate feedback to students' responses, individually tailored instructions, objective testing and entertaining delivery. The end product of this project will serve as interactive material to enhance experiential learning for nursing students using the simulations of cardiac emergency scenaria. The emergency treatment simulations have been developed using VisSim and may be compiled as C code. The objective of the project is to provide a web based user friendly multimedia interface in order to demonstrate the way in which patients may be managed in critical situations by applying advanced technological equipment and drug administration. Then the user will be able to better appreciate the concepts involved by running the VisSim simulations. The evaluation group for the proposed software will be the Department of Nursing and Paramedic Sciences About 200 nurses use simulations every year for training purposes as part of their course requirements.

SFO-Project: The New Generation of Sharable, Editable and Open-Access CFD Tutorials

Science.gov (United States)

Javaherchi, Teymour; Javaherchi, Ardeshir; Aliseda, Alberto

2016-11-01

One of the most common approaches to develop a Computational Fluid Dynamic (CFD) simulation for a new case study of interest is to search for the most similar, previously developed and validated CFD simulation among other works. A simple search would result into a pool of written/visual tutorials. However, users should spend significant amount of time and effort to find the most correct, compatible and valid tutorial in this pool and further modify it toward their simulation of interest. SFO is an open-source project with the core idea of saving the above-mentioned time and effort. This is done via documenting/sharing scientific and methodological approaches to develop CFD simulations for a wide spectrum of fundamental and industrial case studies in three different CFD solvers; STAR-CCM +, FLUENT and Open FOAM (SFO). All of the steps and required files of these tutorials are accessible and editable under the common roof of Github (a web-based Git repository hosting service). In this presentation we will present the current library of 20 + developed CFD tutorials, discuss the idea and benefit of using them, their educational values and explain how the next generation of open-access and live resource of CFD tutorials can be built further hand-in-hand within our community.

Volcano Modelling and Simulation gateway (VMSg): A new web-based framework for collaborative research in physical modelling and simulation of volcanic phenomena

Science.gov (United States)

Esposti Ongaro, T.; Barsotti, S.; de'Michieli Vitturi, M.; Favalli, M.; Longo, A.; Nannipieri, L.; Neri, A.; Papale, P.; Saccorotti, G.

2009-12-01

Physical and numerical modelling is becoming of increasing importance in volcanology and volcanic hazard assessment. However, new interdisciplinary problems arise when dealing with complex mathematical formulations, numerical algorithms and their implementations on modern computer architectures. Therefore new frameworks are needed for sharing knowledge, software codes, and datasets among scientists. Here we present the Volcano Modelling and Simulation gateway (VMSg, accessible at http://vmsg.pi.ingv.it), a new electronic infrastructure for promoting knowledge growth and transfer in the field of volcanological modelling and numerical simulation. The new web portal, developed in the framework of former and ongoing national and European projects, is based on a dynamic Content Manager System (CMS) and was developed to host and present numerical models of the main volcanic processes and relationships including magma properties, magma chamber dynamics, conduit flow, plume dynamics, pyroclastic flows, lava flows, etc. Model applications, numerical code documentation, simulation datasets as well as model validation and calibration test-cases are also part of the gateway material.

Gamma ray observatory dynamics simulator in Ada (GRODY)

International Nuclear Information System (INIS)

1990-09-01

This experiment involved the parallel development of dynamics simulators for the Gamma Ray Observatory in both FORTRAN and Ada for the purpose of evaluating the applicability of Ada to the NASA/Goddard Space Flight Center's flight dynamics environment. The experiment successfully demonstrated that Ada is a viable, valuable technology for use in this environment. In addition to building a simulator, the Ada team evaluated training approaches, developed an Ada methodology appropriate to the flight dynamics environment, and established a baseline for evaluating future Ada projects

Noise and Vibration Risk Prevention Virtual Web for Ubiquitous Training

Science.gov (United States)

Redel-Macías, María Dolores; Cubero-Atienza, Antonio J.; Martínez-Valle, José Miguel; Pedrós-Pérez, Gerardo; del Pilar Martínez-Jiménez, María

2015-01-01

This paper describes a new Web portal offering experimental labs for ubiquitous training of university engineering students in work-related risk prevention. The Web-accessible computer program simulates the noise and machine vibrations met in the work environment, in a series of virtual laboratories that mimic an actual laboratory and provide the…

Angular Spectrum Simulation of Pulsed Ultrasound Fields

DEFF Research Database (Denmark)

Du, Yigang; Jensen, Henrik; Jensen, Jørgen Arendt

2009-01-01

frequencies must be performed. Combining it with Field II, the generation of non-linear simulation for any geometry with any excitation array transducer becomes feasible. The purpose of this paper is to make a general pulsed simulation software using the modified ASA. Linear and phased array transducers......The optimization of non-linear ultrasound imaging should in a first step be based on simulation, as this makes parameter studies considerably easier than making transducer prototypes. Such a simulation program should be capable of simulating non-linear pulsed fields for arbitrary transducer...... geometries for any kind of focusing and apodization. The Angular Spectrum Approach (ASA) is capable of simulating monochromatic non-linear acoustic wave propagation. However, for ultrasound imaging the time response of each specific point in space is required, and a pulsed ASA simulation with multi temporal...

Accessing NASA Technology with the World Wide Web

Science.gov (United States)

Nelson, Michael L.; Bianco, David J.

1995-01-01

NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a Center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer and technology awareness applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology OPportunities Showcase (TOPS), an industrial partnering showcase that exists on the Web long after the actual 3-day event ended. The NASA Technical Report Server (NTRS) provides uniform access to many logically similar, yet physically distributed NASA report servers. WWW is also the foundation of the Langley Software Server (LSS), an experimental software distribution system which will distribute LaRC-developed software. In addition to the more formal technology distribution projects, WWW has been successful in connecting people with technologies and people with other people.

GeneDig: a web application for accessing genomic and bioinformatics knowledge.

Science.gov (United States)

Suciu, Radu M; Aydin, Emir; Chen, Brian E

2015-02-28

With the exponential increase and widespread availability of genomic, transcriptomic, and proteomic data, accessing these '-omics' data is becoming increasingly difficult. The current resources for accessing and analyzing these data have been created to perform highly specific functions intended for specialists, and thus typically emphasize functionality over user experience. We have developed a web-based application, GeneDig.org, that allows any general user access to genomic information with ease and efficiency. GeneDig allows for searching and browsing genes and genomes, while a dynamic navigator displays genomic, RNA, and protein information simultaneously for co-navigation. We demonstrate that our application allows more than five times faster and efficient access to genomic information than any currently available methods. We have developed GeneDig as a platform for bioinformatics integration focused on usability as its central design. This platform will introduce genomic navigation to broader audiences while aiding the bioinformatics analyses performed in everyday biology research.

Pilot Evaluation of a Web-Based Intervention Targeting Sexual Health Service Access

Science.gov (United States)

Brown, K. E.; Newby, K.; Caley, M.; Danahay, A.; Kehal, I.

2016-01-01

Sexual health service access is fundamental to good sexual health, yet interventions designed to address this have rarely been implemented or evaluated. In this article, pilot evaluation findings for a targeted public health behavior change intervention, delivered via a website and web-app, aiming to increase uptake of sexual health services among…

HTSstation: a web application and open-access libraries for high-throughput sequencing data analysis.

Science.gov (United States)

David, Fabrice P A; Delafontaine, Julien; Carat, Solenne; Ross, Frederick J; Lefebvre, Gregory; Jarosz, Yohan; Sinclair, Lucas; Noordermeer, Daan; Rougemont, Jacques; Leleu, Marion

2014-01-01

The HTSstation analysis portal is a suite of simple web forms coupled to modular analysis pipelines for various applications of High-Throughput Sequencing including ChIP-seq, RNA-seq, 4C-seq and re-sequencing. HTSstation offers biologists the possibility to rapidly investigate their HTS data using an intuitive web application with heuristically pre-defined parameters. A number of open-source software components have been implemented and can be used to build, configure and run HTS analysis pipelines reactively. Besides, our programming framework empowers developers with the possibility to design their own workflows and integrate additional third-party software. The HTSstation web application is accessible at http://htsstation.epfl.ch.

Hard x-ray to low energy gamma ray spectrum of the Crab Nebula

International Nuclear Information System (INIS)

Jung, G.V.

1986-01-01

The spectrum of the Crab Nebula has been determined in the energy range 10 keV to 5 MeV from the data of the UCSD/MIT Hard-X-ray and Low Energy Gamma Ray Experiment on the first High Energy Astronomy Observatory, HEAO-1. The x-ray to γ-ray portion of the continuous emission from the Crab is indicative of the electron spectrum, its transport through the nebula, and the physical conditions near the shocked interface between the nebular region and the wind which is the physical link between the nebula and the pulsar, NP0532. The power-law dependence of the spectrum found in the lower-energy decade of this observation (10 to 100 keV) is not continued without modification to higher energies. Evidence for this has been accumulating from previous observations in the γ-ray ranges of 1-10 MeV and above 35 MeV. The observations on which this dissertation is based further characterize the spectral change in the 100 keV to 1 MeV region. These observations provide a crucial connection between the x-ray and γ-ray spectrum of the non-pulsed emission of the Crab Nebula. The continuity of this spectrum suggests that the emission mechanism responsible for the non-pulsed γ-rays observed above 35 MeV is of the same origin as the emission at lower energies, i.e. that of synchrotron radiation in the magnetic field of the nebula

SalanderMaps: A rapid overview about felt earthquakes through data mining of web-accesses

Science.gov (United States)

Kradolfer, Urs

2013-04-01

While seismological observatories detect and locate earthquakes based on measurements of the ground motion, they neither know a priori whether an earthquake has been felt by the public nor is it known, where it has been felt. Such information is usually gathered by evaluating feedback reported by the public through on-line forms on the web. However, after a felt earthquake in Switzerland, many people visit the webpages of the Swiss Seismological Service (SED) at the ETH Zurich and each such visit leaves traces in the logfiles on our web-servers. Data mining techniques, applied to these logfiles and mining publicly available data bases on the internet open possibilities to obtain previously unknown information about our virtual visitors. In order to provide precise information to authorities and the media, it would be desirable to rapidly know from which locations these web-accesses origin. The method 'Salander' (Seismic Activitiy Linked to Area codes - Nimble Detection of Earthquake Rumbles) will be introduced and it will be explained, how the IP-addresses (each computer or router directly connected to the internet has a unique IP-address; an example would be 129.132.53.5) of a sufficient amount of our virtual visitors were linked to their geographical area. This allows us to unprecedentedly quickly know whether and where an earthquake was felt in Switzerland. It will also be explained, why the method Salander is superior to commercial so-called geolocation products. The corresponding products of the Salander method, animated SalanderMaps, which are routinely generated after each earthquake with a magnitude of M>2 in Switzerland (http://www.seismo.ethz.ch/prod/salandermaps/, available after March 2013), demonstrate how the wavefield of earthquakes propagates through Switzerland and where it was felt. Often, such information is available within less than 60 seconds after origin time, and we always get a clear picture within already five minutes after origin time

Statistical analysis for discrimination of prompt gamma ray peak induced by high energy neutron: Monte Carlo simulation study

International Nuclear Information System (INIS)

Do-Kun Yoon; Joo-Young Jung; Tae Suk Suh; Seong-Min Han

2015-01-01

The purpose of this research is a statistical analysis for discrimination of prompt gamma ray peak induced by the 14.1 MeV neutron particles from spectra using Monte Carlo simulation. For the simulation, the information of 18 detector materials was used to simulate spectra by the neutron capture reaction. The discrimination of nine prompt gamma ray peaks from the simulation of each detector material was performed. We presented the several comparison indexes of energy resolution performance depending on the detector material using the simulation and statistics for the prompt gamma activation analysis. (author)

Web survey of sleep problems associated with early-onset bipolar spectrum disorders.

Science.gov (United States)

Lofthouse, Nicholas; Fristad, Mary; Splaingard, Mark; Kelleher, Kelly; Hayes, John; Resko, Susan

2008-05-01

As research on sleep difficulties associated with Early-Onset Bipolar Spectrum Disorders (EBSD) is limited, a web-based survey was developed to further explore these problems. 494 parents of 4-to-12 year-olds, identified by parents as being diagnosed with EBSD, completed a web survey about past and current EBSD-related sleep problems. The survey included Children's Sleep Habits Questionnaire (CSHQ) items and sleep problems from the International Classification of Sleep Disorders 2nd edition. Nearly all parents reported some type of past or current EBSD-sleep problem. Most occurred during a worst mood period, particularly with mixed manic-depressive symptoms. Symptoms caused impairments at home, school, or with peers in 96.9% of the sample and across all three contexts in 64.0% of children. Sleep problems were also noted after three-day weekends and Spring and Fall Daylight Savings time changes. Findings, study limitations, and implications for treatment and etiology are discussed.

Designing Crop Simulation Web Service with Service Oriented Architecture Principle

Science.gov (United States)

Chinnachodteeranun, R.; Hung, N. D.; Honda, K.

2015-12-01

Crop simulation models are efficient tools for simulating crop growth processes and yield. Running crop models requires data from various sources as well as time-consuming data processing, such as data quality checking and data formatting, before those data can be inputted to the model. It makes the use of crop modeling limited only to crop modelers. We aim to make running crop models convenient for various users so that the utilization of crop models will be expanded, which will directly improve agricultural applications. As the first step, we had developed a prototype that runs DSSAT on Web called as Tomorrow's Rice (v. 1). It predicts rice yields based on a planting date, rice's variety and soil characteristics using DSSAT crop model. A user only needs to select a planting location on the Web GUI then the system queried historical weather data from available sources and expected yield is returned. Currently, we are working on weather data connection via Sensor Observation Service (SOS) interface defined by Open Geospatial Consortium (OGC). Weather data can be automatically connected to a weather generator for generating weather scenarios for running the crop model. In order to expand these services further, we are designing a web service framework consisting of layers of web services to support compositions and executions for running crop simulations. This framework allows a third party application to call and cascade each service as it needs for data preparation and running DSSAT model using a dynamic web service mechanism. The framework has a module to manage data format conversion, which means users do not need to spend their time curating the data inputs. Dynamic linking of data sources and services are implemented using the Service Component Architecture (SCA). This agriculture web service platform demonstrates interoperability of weather data using SOS interface, convenient connections between weather data sources and weather generator, and connecting

A web-based repository of surgical simulator projects.

Science.gov (United States)

Leskovský, Peter; Harders, Matthias; Székely, Gábor

2006-01-01

The use of computer-based surgical simulators for training of prospective surgeons has been a topic of research for more than a decade. As a result, a large number of academic projects have been carried out, and a growing number of commercial products are available on the market. Keeping track of all these endeavors for established groups as well as for newly started projects can be quite arduous. Gathering information on existing methods, already traveled research paths, and problems encountered is a time consuming task. To alleviate this situation, we have established a modifiable online repository of existing projects. It contains detailed information about a large number of simulator projects gathered from web pages, papers and personal communication. The database is modifiable (with password protected sections) and also allows for a simple statistical analysis of the collected data. For further information, the surgical repository web page can be found at www.virtualsurgery.vision.ee.ethz.ch.

e-Gamma: Nuclear Material Accountancy and Control System in Brazil

International Nuclear Information System (INIS)

Negri Ferreira, S.; Souza Dunley, L.

2015-01-01

The Brazilian Nuclear Energy Commission (CNEN) is the government organization responsible for regulating all nuclear activities in Brazil and for ensuring that international safeguards are implemented according to the international agreements. In 2006 CNEN initiated a project aiming at the development and implementation of a web based system (e-Gamma) for on line nuclear material accountancy and control. In January-2014, after three years of beta testing, e-Gamma finally became the official nuclear material accountancy system in Brazil. e-Gamma is a web system hosted in a dedicated server under a secure environment maintained at CNEN headquarters. Secure access is provided by the use of Digital Client Certificate and internal user pre-authorization for login as well as multiple access profiles each one with specific function menus. The System operation is based on source documents for each inventory change prepared and updated by the MBA operators with the help of specific forms with strong validations. After the document conclusion the System records the inventory change in a general ledger. Monthly the officers of CNEN analyzes the general ledgers of each MBA and generates the applicable reports through the System [Inventory Change Reports (ICR), Physical Inventory List (PIL), and Material Balance Report (MBR)]. The System allows the running of managerial queries and has brought to CNEN much more control and traceability of the inventory changes and significant reduction in typing errors, costs and inspection efforts. Therefore, more efficient accountancy verification procedures at national and international levels are expected, as well as remote accountancy verification previous to an inspection. The proposed paper will describe the e-Gamma System, its main features and the oral presentation will contain a brief demonstration of some functionalities through the use of a local version installed on a notebook. (author)

Particle transport simulation for spaceborne, NaI gamma-ray spectrometers

International Nuclear Information System (INIS)

Dyer, C.S.; Truscott, P.R.; Sims, A.J.; Comber, C.; Hammond, N.D.A.

1988-11-01

Radioactivity induced in detectors by protons and secondary neutrons limits the sensitivity of spaceborne gamma-ray spectrometers. Three dimensional Monte Carlo transport codes have been employed to simulate particle transport of cosmic rays and inner-belt protons in various representations of the Gamma Ray Observatory Spacecraft and the Oriented Scintillation Spectrometer Experiment. Results are used to accurately quantify the contributions to the radioactive background, assess shielding options and examine the effect of detector and space-craft orientation in anisotropic trapped proton fluxes. (author)

Enhancing Accessibility of Web Content for the Print-Impaired and Blind People

Science.gov (United States)

Chalamandaris, Aimilios; Raptis, Spyros; Tsiakoulis, Pirros; Karabetsos, Sotiris

Blind people and in general print-impaired people are often restricted to use their own computers, enhanced most often with expensive, screen reading programs, in order to access the web, and in a form that every screen reading program allows to. In this paper we present SpellCast Navi, a tool that is intended for people with visual impairments, which attempts to combine advantages from both customized and generic web enhancement tools. It consists of a generically designed engine and a set of case-specific filters. It can run on a typical web browser and computer, without the need of installing any additional application locally. It acquires and parses the content of web pages, converts bi-lingual text into synthetic speech using high quality speech synthesizer, and supports a set of common functionalities such as navigation through hotkeys, audible navigation lists and more. By using a post-hoc approach based on a-priori information of the website's layout, the audible presentation and navigation through the website is more intuitive a more efficient than with a typical screen reading application. SpellCast Navi poses no requirements on web pages and introduces no overhead to the design and development of a website, as it functions as a hosted proxy service.

Simulation of neutrons and gamma pulse signal and research on the pulse shape discrimination technology

International Nuclear Information System (INIS)

Zuo Guangxia; He Bin; Xu Peng; Qiu Xiaolin; Ma Wenyan; Li Sufen

2012-01-01

In neutrons detection, it is important to discriminate the neutron signals from the gamma-ray background. In this article, simulation of neutrons and gamma pulse signals is developed based on the LabVIEW platform. Two digital algorithms of the charge comparison method and the pulse duration time method are realized using 10000 simulation signals. Experimental results show that neutron and gamma pulse signals can be discriminated by the two methods, and the pulse duration time method is better than the charge comparison method. (authors)

PERFORMANCE OPTIMIZATION OF COGNITIVE RADIO WITH WIDEBAND SPECTRUM SENSING

Directory of Open Access Journals (Sweden)

E. Saraniya

2014-09-01

Full Text Available Cognitive radio (CR technology allows the unlicensed user to access the licensed spectrum bands. Spectrum sensing is an essential function in cognitive radio to detect the spectrum holes and opportunistically use the underutilized frequency bands without causing interference to primary user (PU. In this paper we are maximizing the throughput capacity of cognitive radio user and hence the performance of spectrum sensing and protection to licensed user improves over a wideband spectrum sensing band. The simulation of cognitive radio is done by analyzing the performance of energy detector spectrum sensing technique to detect primary user and to formulate the optimization using multiband joint detection method (MJD to achieve suitable trade- off between secondary user access and primary user network. The main aim of this paper is to maximize the probability of detection and to decrease the probabilities of miss detection and false alarm. To maximize the throughput it requires minimizing the throughput loss caused by miss detection and the significant reduction in probability of false alarm helps in achieving the spectral efficiency from the secondary user’s perspective. The simulation results show that the performance increases with the MJD method.

Capture Gamma-Ray Libraries for Nuclear Applications

International Nuclear Information System (INIS)

Sleaford, B.W.; Firestone, Richard B.; Summers, N.; Escher, J.; Hurst, A.; Krticka, M.; Basunia, S.; Molnar, G.; Belgya, T.; Revay, Z.; Choi, H.D.

2010-01-01

The neutron capture reaction is useful in identifying and analyzing the gamma-ray spectrum from an unknown assembly as it gives unambiguous information on its composition. This can be done passively or actively where an external neutron source is used to probe an unknown assembly. There are known capture gamma-ray data gaps in the ENDF libraries used by transport codes for various nuclear applications. The Evaluated Gamma-ray Activation file (EGAF) is a new thermal neutron capture database of discrete line spectra and cross sections for over 260 isotopes that was developed as part of an IAEA Coordinated Research Project. EGAF has been used to improve the capture gamma production in ENDF libraries. For medium to heavy nuclei the quasi continuum contribution to the gamma cascades is not experimentally resolved. The continuum contains up to 90% of all the decay energy an is modeled here with the statistical nuclear structure code DICEBOX. This code also provides a consistency check of the level scheme nuclear structure evaluation. The calculated continuum is of sufficient accuracy to include in the ENDF libraries. This analysis also determines new total thermal capture cross sections and provides an improved RIPL database. For higher energy neutron capture there is less experimental data available making benchmarking of the modeling codes more difficult. We use CASINO, a version of DICEBOX that is modified for this purpose. This can be used to simulate the neutron capture at incident neutron energies up to 20 MeV to improve the gamma-ray spectrum in neutron data libraries used for transport modelling of unknown assemblies.

Verification of Parent-Report of Child Autism Spectrum Disorder Diagnosis to a Web-Based Autism Registry

Science.gov (United States)

Daniels, Amy M.; Rosenberg, Rebecca E.; Anderson, Connie; Law, J. Kiely; Marvin, Alison R.; Law, Paul A.

2012-01-01

Growing interest in autism spectrum disorder (ASD) research requires increasingly large samples to uncover epidemiologic trends; such a large dataset is available in a national, web-based autism registry, the Interactive Autism Network (IAN). The objective of this study was to verify parent-report of professional ASD diagnosis to the registry's…

PC based simulation of gamma camera for training of operating and maintenance staff

International Nuclear Information System (INIS)

Singh, B.; Kataria, S.K.; Samuel, A.M.

2000-01-01

Gamma camera- a sophisticated imaging system is used for functional assessment of biological subsystems/organs in nuclear medicine. The radioactive tracer attached to the native substance is injected into the patient. The distribution of radioactivity in the patient is imaged by the gamma camera. This report describes a PC based package for simulation of gamma cameras and effect of malfunctioning of its subsystems on images of different phantoms

Internet access, awareness and utilisation of web based evidence: a survey of ANZ and Singaporean radiation oncology registrars in 2003

International Nuclear Information System (INIS)

Wong, K.; Veness, M.

2003-01-01

The past decade has seen an 'explosion' in electronically archived evidence available on the Internet. Access to, and awareness of, pre-appraised web based evidence such as is available at the Cochrane Library, and more recently the Cancer Library, is now easily accessible to both clinicians and patients. A postal survey was recently sent out to all Radiation Oncology registrars in Australia, New Zealand and Singapore. The aim of the survey was to ascertain previous training in literature searching and critical appraisal, the extent of Internet access and use of web based evidence and awareness of databases including the Cochrane Library. Sixty six (66) out of ninety (90) registrars responded (73% response rate). Fifty five percent of respondents had previously undertaken some form of training related to literature searching or critical appraisal. The majority (68%) felt confident in performing a literature search, although 80% of respondents indicated interest in obtaining further training. The majority (68%) reported accessing web-based evidence for literature searching in the previous week, and 92% in the previous month. Nearly all respondents (89%) accessed web-based evidence at work. Most (94%) were aware of the Cochrane Library with 48% of respondents having used this database. Sixty-eight percent were aware of the Cancer Library. In 2000 a similar survey revealed only 68% of registrars aware and 30% having used the Cochrane Library. These findings reveal almost universal access to the Internet and use of web-based evidence amongst Radiation Oncology registrars. There has been a marked increase in awareness and use of the Cochrane Library with the majority also aware of the recently introduced Cancer Library

Gamma irradiator dose mapping simulation using the MCNP code and benchmarking with dosimetry

International Nuclear Information System (INIS)

Sohrabpour, M.; Hassanzadeh, M.; Shahriari, M.; Sharifzadeh, M.

2002-01-01

The Monte Carlo transport code, MCNP, has been applied in simulating dose rate distribution in the IR-136 gamma irradiator system. Isodose curves, cumulative dose values, and system design data such as throughputs, over-dose-ratios, and efficiencies have been simulated as functions of product density. Simulated isodose curves, and cumulative dose values were compared with dosimetry values obtained using polymethyle-methacrylate, Fricke, ethanol-chlorobenzene, and potassium dichromate dosimeters. The produced system design data were also found to agree quite favorably with those of the system manufacturer's data. MCNP has thus been found to be an effective transport code for handling of various dose mapping excercises for gamma irradiators

The new ALICE DQM client: a web access to ROOT-based objects

International Nuclear Information System (INIS)

Von Haller, B; Carena, F; Carena, W; Chapeland, S; Barroso, V Chibante; Costa, F; Delort, C; Diviá, R.; Fuchs, U; Niedziela, J; Simonetti, G; Soós, C; Telesca, A; Vyvre, P Vande; Wegrzynek, A; Dénes, E

2015-01-01

A Large Ion Collider Experiment (ALICE) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). The online Data Quality Monitoring (DQM) plays an essential role in the experiment operation by providing shifters with immediate feedback on the data being recorded in order to quickly identify and overcome problems.An immediate access to the DQM results is needed not only by shifters in the control room but also by detector experts worldwide. As a consequence, a new web application has been developed to dynamically display and manipulate the ROOT-based objects produced by the DQM system in a flexible and user friendly interface.The architecture and design of the tool, its main features and the technologies that were used, both on the server and the client side, are described. In particular, we detail how we took advantage of the most recent ROOT JavaScript I/O and web server library to give interactive access to ROOT objects stored in a database. We describe as well the use of modern web techniques and packages such as AJAX, DHTMLX and jQuery, which has been instrumental in the successful implementation of a reactive and efficient application.We finally present the resulting application and how code quality was ensured. We conclude with a roadmap for future technical and functional developments. (paper)

A virtual source method for Monte Carlo simulation of Gamma Knife Model C

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Hoon; Kim, Yong Kyun [Hanyang University, Seoul (Korea, Republic of); Chung, Hyun Tai [Seoul National University College of Medicine, Seoul (Korea, Republic of)

2016-05-15

The Monte Carlo simulation method has been used for dosimetry of radiation treatment. Monte Carlo simulation is the method that determines paths and dosimetry of particles using random number. Recently, owing to the ability of fast processing of the computers, it is possible to treat a patient more precisely. However, it is necessary to increase the simulation time to improve the efficiency of accuracy uncertainty. When generating the particles from the cobalt source in a simulation, there are many particles cut off. So it takes time to simulate more accurately. For the efficiency, we generated the virtual source that has the phase space distribution which acquired a single gamma knife channel. We performed the simulation using the virtual sources on the 201 channel and compared the measurement with the simulation using virtual sources and real sources. A virtual source file was generated to reduce the simulation time of a Gamma Knife Model C. Simulations with a virtual source executed about 50 times faster than the original source code and there was no statistically significant difference in simulated results.

A virtual source method for Monte Carlo simulation of Gamma Knife Model C

International Nuclear Information System (INIS)

Kim, Tae Hoon; Kim, Yong Kyun; Chung, Hyun Tai

2016-01-01

The Monte Carlo simulation method has been used for dosimetry of radiation treatment. Monte Carlo simulation is the method that determines paths and dosimetry of particles using random number. Recently, owing to the ability of fast processing of the computers, it is possible to treat a patient more precisely. However, it is necessary to increase the simulation time to improve the efficiency of accuracy uncertainty. When generating the particles from the cobalt source in a simulation, there are many particles cut off. So it takes time to simulate more accurately. For the efficiency, we generated the virtual source that has the phase space distribution which acquired a single gamma knife channel. We performed the simulation using the virtual sources on the 201 channel and compared the measurement with the simulation using virtual sources and real sources. A virtual source file was generated to reduce the simulation time of a Gamma Knife Model C. Simulations with a virtual source executed about 50 times faster than the original source code and there was no statistically significant difference in simulated results

Proof-of-Concept System for Opportunistic Spectrum Access in Multi-user Decentralized Networks

Directory of Open Access Journals (Sweden)

Sumit J. Darak

2016-09-01

Full Text Available Poor utilization of an electromagnetic spectrum and ever increasing demand for spectrum have led to surge of interests in opportunistic spectrum access (OSA based paradigms like cognitive radio and unlicensed LTE. In OSA for decentralized networks, frequency band selection from wideband spectrum is a challenging task since secondary users (SUs do not share any information with each other. In this paper, a new decision making policy (DMP has been proposed for OSA in the multi-user decentralized networks. First contribution is an accurate characterization of frequency bands using Bayes-UCB algorithm. Then, a novel SU orthogonization scheme using Bayes-UCB algorithm is proposed replacing randomization based scheme. At the end, USRP testbed has been developed for analyzing the performance of DMPs using real radio signals. Experimental results show that the proposed DMP offers significant improvement in spectrum utilization, fewer subband switching and collisions compared to other DMPs.

Lead foil wrapping of the plastic scintillators for the gamma ray detection: optical reflector or spectrum intensifier?

International Nuclear Information System (INIS)

Taheri, A.; Askari, M.; Sasanpour, M. Taghan

2017-01-01

This paper studies the effect of lead wrapping on the response of the plastic scintillators as gamma detectors. Experimental tests and Geant4 simulations showed that lead wrapping cannot increase the gamma absorption efficiency of the detector but, as a reflector, it can improve the optical properties of the detector. The reflectivity of the lead foil as an optical reflector was determined equal to 66% using an experimental-simulation combined method. Based on the obtained results, the optical collection efficiency of the detector was also increased about 4% after employing the lead reflector.

Basics of Gamma Ray Detection

Energy Technology Data Exchange (ETDEWEB)

Stinnett, Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Venkataraman, Ram [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-09-13

The objective of this training is to explain the origin of x-rays and gamma rays, gamma ray interactions with matter, detectors and electronics used in gamma ray-spectrometry, and features of a gamma-ray spectrum for nuclear material that is safeguarded.

A method for measuring the energy spectrum of coincidence events in positron emission tomography.

Science.gov (United States)

Goertzen, Andrew L; Stout, David B; Thompson, Christopher J

2010-01-21

Positron emission tomography (PET) system energy response is typically characterized in singles detection mode, yet there are situations in which the energy spectrum of coincidence events might be different than the spectrum measured in singles mode. Examples include imaging with isotopes that emit a prompt gamma in coincidence with a positron emission, imaging with low activity in a LSO/LYSO-based cameras, in which the intrinsic activity is significant, and in high scatter situations where the two 511 keV photons have different scattering probabilities (i.e. off-center line source). The ability to accurately measure the energy spectrum of coincidence events could be used for validating simulation models, optimizing energy discriminator levels and examining scatter models and corrections. For many PET systems operating in coincidence mode, the only method available for estimating the energy spectrum is to step the lower and upper level discriminators (LLD and ULD). Simple measurement techniques such as using a narrow sliding energy window or stepping only the LLD will not yield a spectrum of coincidence events that is accurate for cases where there are different energy components contributing to the spectrum. In this work we propose a new method of measuring the energy spectrum of coincidence events in PET based on a linear combination of two sets of coincident count measurements: one made by stepping the LLD and one made by stepping the ULD. The method was tested using both Monte Carlo simulations of a Siemens microPET R4 camera and measured data acquired on a Siemens Inveon PET camera. The results show that our energy spectrum calculation method accurately measures the coincident energy spectra for cases including the beta/gamma spectrum of the (176)Lu intrinsic activity present in the LSO scintillator crystals, a (68)Ge source and an (124)I source (in which there are prompt gamma-rays emitted together with the positron).

Web: A Wireless Experiment Box for the Dextre Pointing Package ELC Payload

Science.gov (United States)

Bleier, Leor Z.; Marrero-Fontanez, Victor J.; Sparacino, Pietro A.; Moreau, Michael C.; Mitchell, Jason W.

2012-01-01

The Wireless Experiment Box (WEB) was proposed to work with the International Space Station (ISS) External Wireless Communication (EWC) system to support high-definition video from the Dextre Pointing Package (DPP). DPP/WEB was a NASA GSFC proposed ExPRESS Logistics Carrier (ELC) payload designed to flight test an integrated suite of Autonomous Rendezvous and Docking (AR&D) technologies to enable a wide spectrum of future missions across NASA and other US Government agencies. The ISS EWC uses COTS Wireless Access Points (WAPs) to provide high-rate bi-directional communications to ISS. In this paper, we discuss WEB s packaging, operation, antenna development, and performance testing.

WEB - A Wireless Experiment Box for the Dextre Pointing Package ELC Payload

Science.gov (United States)

Bleier, Leor Z.; Marrero-Fontanez, Victor J.; Sparacino, Pietro A.; Moreau, Michael C.; Mitchell, Jason William

2012-01-01

The Wireless Experiment Box (WEB) was proposed to work with the International Space Station (ISS) External Wireless Communication (EWC) system to support high-definition video from the Dextre Pointing Package (DPP). DPP/WEB was a NASA GSFC proposed ExPRESS Logistics Carrier (ELC) payload designed to flight test an integrated suite of Autonomous Rendezvous and Docking (AR&D) technologies to enable a wide spectrum of future missions across NASA and other US Government agencies. The ISS EWC uses COTS Wireless Access Points (WAPs) to provide high-rate bi-directional communications to ISS. In this paper, we discuss WEB s packaging, operation, antenna development, and performance testing.

A spectrum of power plant simulators for effective training

International Nuclear Information System (INIS)

Foulke, L.R.

1987-01-01

This paper discusses the subject of training simulator fidelity and describes a spectrum of fidelity levels of power plant simulators to optimize training effectiveness. The body of knowledge about the relationship between power plant simulator fidelity and training effectiveness is reviewed, and a number of conjectures about this relationship are made based on the perspective of over 20 simulator-years of experience in training nuclear power plant operators. Developments are described for a new class of emerging simulator which utilize high resolution graphics to emphasize the visualization step of effective training

Sensitivity of self-powered detector probes to electron and gamma-ray fields

Energy Technology Data Exchange (ETDEWEB)

Lone, M A; Wong, P Y [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

1996-12-31

A self-powered detector (SPD) is a simple, passive device that consists of a coaxial probe with a metallic outer sleeve, a mineral oxide insulating layer, and a metallic inner core. SPD`s are used in nuclear reactors to monitor neutron and gamma fields. Responses of SPD`s to electrons and {gamma}-rays of various energies were investigated with Monte Carlo simulations. Transmission filters were studied for the design of threshold SPD probes used for online monitoring of the energy spectrum of high-power industrial electron accelerator beams. Filters were also investigated for the enhancement of {gamma}-ray sensitivity of an SPD placed in a mixed electron and {gamma}-ray field. (author). 30 refs., 1 tab., 8 figs.

Sodium fast reactor power monitoring using gamma spectrometry

Energy Technology Data Exchange (ETDEWEB)

Coulon, R.; Normand, S.; Barbot, L.; Domenech, T.; Kondrasovs, V.; Corre, G.; Frelin, A.M. [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, CEA - Saclay DRT/LIST/DETECS/SSTM, Batiment 516 - P.C. no 72, Gif sur Yvette, F-91191 (France); Montagu, T.; Dautremer, T.; Barat, E. [CEA, LIST, Laboratoire Processus Stochastiques et Spectres (France); Ban, G. [ENSICAEN (France)

2009-06-15

This work deals with the use of high flux gamma spectrometry to monitor the fourth generation of sodium fast reactor (SFR) power. The simulation study part of this work has shown that power monitoring in a short time response and with a good accuracy is possible. An experimental test is under preparation at the French SFR Phenix experimental reactor to validate simulation studies. First, physical calculations have been done to correlate gamma activity to the released thermal power. Gamma emitter production rate in the reactor core was calculated with technical and nuclear data as the sodium velocity, the atomic densities, Phenix neutron spectrum and incident neutron cross-sections of reactions producing gamma emitters. A thermal hydraulic transfer function was used for modeling primary sodium flow in our calculations. For the power monitoring problematic, use of a short decay period gamma emitter will allow to have a very fast response system without cumulative effect. We have determined that the best tagging agent is 20F which emits 1634 keV energy photons with a decay period of 11 s. The gamma spectrum was determined by flux point and a pulse high tally MCNP5.1.40 simulation and shown the possibility to measure the signal of this radionuclide. The experiment will be set during the reactor 'end life testing'. The Delayed Neutron Detection (DND) room has been chosen as the best available location on Phenix reactor to measure this kind of radionuclide due to a short transit time from reactor core to measurement sample. This location is optimum for global power measurement because homogenized sampling in the reactor hot pool. The main spectrometer is composed of a coaxial high purity germanium diode (HPGe) coupled with a transistor reset preamplifier. The HPGe diode signal will be processed by the Adonis digital signal processing due to high flux and fast activity measurement. Post-processing softwares will be used to limit statistical problems of the

Setting scene for TV white spaces and dynamic spectrum access in South Africa

CSIR Research Space (South Africa)

Masonta, MT

2012-05-01

Full Text Available -and-control static spectrum regulation regime. In order to keep up with a growing demand for wireless broadband access; new and dynamic spectrum regulation and management approaches are crucial. The ongoing global television (TV) broadcast digital switchover (DSO... ?white spaces? (TVWS). In the US, for example, TV DSO was completed in June 2009. However, this was not a smooth process. For instance, it was reported that digital TV viewers from many cities experienced several reception problems [2]. Due...

Simulation of Neutron-Induced Prompt Gamma-ray Spectra Emitted from Fake Tungsten Gold Bar

Energy Technology Data Exchange (ETDEWEB)

Lee, K. M.; Sum, G. M. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Fake gold bars on the market cannot be identified easily without testing because they have the same appearance as a pure gold bar. A non-destructive monitoring method is needed to avoid the trading of fake gold bars on the market. The ultimate goal of this study is to find a fake gold bar detection method using a PGAA (Prompt Gamma Activation Analysis). Using existing data, the number of neutron capture for gold and tungsten in fake tungsten gold bar was calculated and a Monte Carlo simulation for the prompt neutron-induced gamma-ray spectra was conducted. A simulation for neutron-induced prompt gamma-rays spectra when a neutron beam is irradiated onto pure and fake gold bars was successfully conducted. Through a comparison between the prompt gamma-ray spectra of the pure gold bar and those of the fake gold bar, it was concluded that the observation of prompt high-energy gamma-rays from tungsten or a reduction of prompt gamma-rays from gold can be evidence of a fake gold bar. The possibility for detecting a fake gold bar using a PGAA facility was verified.

Simulation of Neutron-Induced Prompt Gamma-ray Spectra Emitted from Fake Tungsten Gold Bar

International Nuclear Information System (INIS)

Lee, K. M.; Sum, G. M.

2016-01-01

Fake gold bars on the market cannot be identified easily without testing because they have the same appearance as a pure gold bar. A non-destructive monitoring method is needed to avoid the trading of fake gold bars on the market. The ultimate goal of this study is to find a fake gold bar detection method using a PGAA (Prompt Gamma Activation Analysis). Using existing data, the number of neutron capture for gold and tungsten in fake tungsten gold bar was calculated and a Monte Carlo simulation for the prompt neutron-induced gamma-ray spectra was conducted. A simulation for neutron-induced prompt gamma-rays spectra when a neutron beam is irradiated onto pure and fake gold bars was successfully conducted. Through a comparison between the prompt gamma-ray spectra of the pure gold bar and those of the fake gold bar, it was concluded that the observation of prompt high-energy gamma-rays from tungsten or a reduction of prompt gamma-rays from gold can be evidence of a fake gold bar. The possibility for detecting a fake gold bar using a PGAA facility was verified

Game-theoretic interference coordination approaches for dynamic spectrum access

CERN Document Server

Xu, Yuhua

2016-01-01

Written by experts in the field, this book is based on recent research findings in dynamic spectrum access for cognitive radio networks. It establishes a game-theoretic framework and presents cutting-edge technologies for distributed interference coordination. With game-theoretic formulation and the designed distributed learning algorithms, it provides insights into the interactions between multiple decision-makers and the converging stable states. Researchers, scientists and engineers in the field of cognitive radio networks will benefit from the book, which provides valuable information, useful methods and practical algorithms for use in emerging 5G wireless communication.

SU-G-IeP4-12: Performance of In-111 Coincident Gamma-Ray Counting: A Monte Carlo Simulation

Energy Technology Data Exchange (ETDEWEB)

Pahlka, R; Kappadath, S; Mawlawi, O [UT MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: The decay of In-111 results in a non-isotropic gamma-ray cascade, which is normally imaged using a gamma camera. Creating images with a gamma camera using coincident gamma-rays from In-111 has not been previously studied. Our objective was to explore the feasibility of imaging this cascade as coincidence events and to determine the optimal timing resolution and source activity using Monte Carlo simulations. Methods: GEANT4 was used to simulate the decay of the In-111 nucleus and to model the gamma camera. Each photon emission was assigned a timestamp, and the time delay and angular separation for the second gamma-ray in the cascade was consistent with the known intermediate state half-life of 85ns. The gamma-rays are transported through a model of a Siemens dual head Symbia “S” gamma camera with a 5/8-inch thick crystal and medium energy collimators. A true coincident event was defined as a single 171keV gamma-ray followed by a single 245keV gamma-ray within a specified time window (or vice versa). Several source activities (ranging from 10uCi to 5mCi) with and without incorporation of background counts were then simulated. Each simulation was analyzed using varying time windows to assess random events. The noise equivalent count rate (NECR) was computed based on the number of true and random counts for each combination of activity and time window. No scatter events were assumed since sources were simulated in air. Results: As expected, increasing the timing window increased the total number of observed coincidences albeit at the expense of true coincidences. A timing window range of 200–500ns maximizes the NECR at clinically-used source activities. The background rate did not significantly alter the maximum NECR. Conclusion: This work suggests coincident measurements of In-111 gamma-ray decay can be performed with commercial gamma cameras at clinically-relevant activities. Work is ongoing to assess useful clinical applications.

Web Archiving: Issues and Problems in Collection Building and Access

Directory of Open Access Journals (Sweden)

Grethe Jacobsen

2008-12-01

Full Text Available Denmark began web archiving in 2005 and the experiences are presented with a specific focus on collection-building and issues concerning access. In creating principles for what internet materials to collect for a national collection, one can in many ways build on existing practice and guidelines. The actual collection requires strategies for harvesting relevant segments of the internet in order to assure as complete a coverage as possible. Rethinking is also necessary when it comes to the issue of description, but cataloguing expertise can be utilised to find new ways for users to retrieve information. Technical problems in harvesting and archiving are identifiable and can be solved through international cooperation. Access to the archived materials, on the other hand, has become the major challenge to national libraries. Legal obstacles prevent national libraries from offering generel access to their archived internet materials. In Europe the principal obstacles are the EU Directive on Data Protection (Directive 95/46/EC and local data protection legislation based on this directive. LIBER is urged to take political action on this issue in order that the general public may have the same access to the collection of internet materials as it has to other national collections.

Gamma-irradiated scrub typhus immunogens: broad-spectrum immunity with combinations of rickettsial strains

International Nuclear Information System (INIS)

Eisenberg, G.H. Jr.; Osterman, J.V.

1979-01-01

Scrub typhus immunogens were prepared from Rickettsia tsutsugamushi strains Karp, Kato, Gilliam, Kostival, and Buie by exposing frozen infected yolk sac suspensions to 300 krad of gamma radiation. Mouse protection tests showed that each of the irradiated immunogens protected C3H/HeDub mice against high challenge levels of Karp and Gilliam, but that none of these single-strain immunogens were capable of protecting against all five of the challenge strains. Broad-spectrum protection was achieved by using combinations of three strains of irradiated rickettsiae in a vaccination regimen of three injections at 5-day intervals

Development of an airborne gamma radiation system for snow surveys

Energy Technology Data Exchange (ETDEWEB)

Fritzsche, A E [EG and G, Inc., Las Vegas, NV (USA)

1979-01-01

An airborne gamma-snow survey system requires detailed design to obtain maximum precision and accuracy. The use of NaI(Te) gamma detectors with a full gamma energy spectrum pulse height analyzer together with a small computer provide a self-contained and flexible system. The dual detector method determines atmospheric radon perturbations in the detection system. Detailed calibration experiments must be performed to determine twenty parameters that describe the physical nature of the system. Multiple high altitude and lake flights are used to obtain background components. Simulation pads, loaded with varying concentrations of /sup 40/K, /sup 232/Th and /sup 23/..gamma..U yield photopeak stripping coefficients and basic system sensitivity. Multiple altitude flights over land lines provide air attenuation coefficients which may converted to water attenuation coefficients.

Utilizing experimentally derived multi-channel gamma-ray spectra for the analysis of airborne data

International Nuclear Information System (INIS)

Grasty, R.L.

1982-01-01

Gamma-ray spectra derived from measurements on radioactive concrete calibration pads using plywood sheets to simulate the attenuation effect of air have been successfully tested on airbone data. Cesium-137 at 662 keV, from atomic weapons tests was found to contribute significantly to the airborne spectrum. By fitting the experimental spectra, above the cesium energy, to airborne data, significant increases in accuracy were obtained for the measurement of uranium and thorium, compared to the standard 3-window method. By including a cesium spectrum is the analysis of gamma-ray data from a survey carried out in Saskatchewan, it was found that background radiation due to atmospheric bismuth-214 could be measured more reliably than by using a constant over-water background. Similar results were obtained by monitoring low energy lead-214 gamma-rays at 352 keV

Secondary access based on sensing and primary ARQ feedback in spectrum sharing systems

KAUST Repository

Hamza, Doha R.

2012-04-01

In the context of primary/secondary spectrum sharing, we propose a randomized secondary access strategy with access probabilities that are a function of both the primary automatic repeat request (ARQ) feedback and the spectrum sensing outcome. The primary terminal operates in a time slotted fashion and is active only when it has a packet to send. The primary receiver can send a positive acknowledgment (ACK) when the received packet is decoded correctly. Lack of ARQ feedback is interpreted as erroneous reception or inactivity. We call this the explicit ACK scheme. The primary receiver may also send a negative acknowledgment (NACK) when the packet is received in error. Lack of ARQ feedback is interpreted as an ACK or no-transmission. This is called the explicit NACK scheme. Under both schemes, when the primary feedback is interpreted as a NACK, the secondary user assumes that there will be retransmission in the next slot and accesses the channel with a certain probability. When the primary feedback is interpreted as an ACK, the secondary user accesses the channel with either one of two probabilities based on the sensing outcome. Under these settings, we find the three optimal access probabilities via maximizing the secondary throughput given a constraint on the primary throughput. We compare the performance of the explicit ACK and explicit NACK schemes and contrast them with schemes based on either sensing or primary ARQ feedback only. © 2012 IEEE.

Language Barriers Impact Access to Services for Children with Autism Spectrum Disorders

Science.gov (United States)

St. Amant, Helaine G.; Schrager, Sheree M.; Peña-Ricardo, Carolina; Williams, Marian E.; Vanderbilt, Douglas L.

2018-01-01

Racial and ethnic disparities in accessing health care have been described in children with autism spectrum disorder (ASD). In a retrospective chart review of 152 children with ASD, children of parents whose primary language was English were significantly more likely to have both social skills and communication goals within their individualized…

Remote Instrument Control with CIMA Web Services and Web 2.0 Technology

Directory of Open Access Journals (Sweden)

Douglas John du Boulay

2008-02-01

Full Text Available The Common Instrument Middleware Architecture (CIMA model for Web services based monitoring of remote scientific instruments is being extended and enhanced to provide a capability for remote instrument control. X-ray diffraction has been selected as an ideal domain for prototype development, with the goal being a comprehensive and feature rich portal system for access to remote instruments and their data. The system has two principle components, one of which serves the instrument and data, and the second serves the client user. Plugin modules are used to provide flexibility and re-use, and the notion of plugin control is being developed. The architecture supports remote access to multiple instruments from a single portal. The use of Web 2.0 Pushlet and AJAX technologies has been introduced for push based portlet refresh and updating. An X3D based 3D virtual representation of the instrument provides data collection simulation and (pseudo real time instrument representation.

Visual gamma-ray analysis. VIPF program (WINDOW 95)

International Nuclear Information System (INIS)

Yamada, S.

1998-01-01

VIsual Peak Fitting (VIPF) program for the analysis of gamma radiation peaks from Ge detectors which works on WINDOWS 95 as an operating system has been developed. Gamma-ray peaks are simulated as Gauss function with 1st- or 2nd-order polynomial function for the background spectrum. Any function can be further added to for parameter fitting. The VIPF program can be obtained through internet by down-loading: http://w3.rri.kyoto-u.ac.jp/~yamada. Details of the program procedure, explanation of the fitting function to be used and peak search routine, and manuals of the code are given. (Ohno, S.)

Growth and structure of the World Wide Web: Towards realistic modeling

Science.gov (United States)

Tadić, Bosiljka

2002-08-01

We simulate evolution of the World Wide Web from the dynamic rules incorporating growth, bias attachment, and rewiring. We show that the emergent double-hierarchical structure with distinct distributions of out- and in-links is comparable with the observed empirical data when the control parameter (average graph flexibility β) is kept in the range β=3-4. We then explore the Web graph by simulating (a) Web crawling to determine size and depth of connected components, and (b) a random walker that discovers the structure of connected subgraphs with dominant attractor and promoter nodes. A random walker that adapts its move strategy to mimic local node linking preferences is shown to have a short access time to "important" nodes on the Web graph.

Towards automated processing of the right of access in inter-organizational Web Service compositions

DEFF Research Database (Denmark)

Herkenhöner, Ralph; De Meer, Hermann; Jensen, Meiko

2010-01-01

with trade secret protection. In this paper, we present an automated architecture to enable exercising the right of access in the domain of inter-organizational business processes based on Web Services technology. Deriving its requirements from the legal, economical, and technical obligations, we show...

Phenotypic spectrum associated with mutations of the mitochondrial polymerase gamma gene.

Science.gov (United States)

Horvath, Rita; Hudson, Gavin; Ferrari, Gianfrancesco; Fütterer, Nancy; Ahola, Sofia; Lamantea, Eleonora; Prokisch, Holger; Lochmüller, Hanns; McFarland, Robert; Ramesh, V; Klopstock, Thomas; Freisinger, Peter; Salvi, Fabrizio; Mayr, Johannes A; Santer, Rene; Tesarova, Marketa; Zeman, Jiri; Udd, Bjarne; Taylor, Robert W; Turnbull, Douglass; Hanna, Michael; Fialho, Doreen; Suomalainen, Anu; Zeviani, Massimo; Chinnery, Patrick F

2006-07-01

Mutations in the gene coding for the catalytic subunit of the mitochondrial DNA (mtDNA) polymerase gamma (POLG1) have recently been described in patients with diverse clinical presentations, revealing a complex relationship between genotype and phenotype in patients and their families. POLG1 was sequenced in patients from different European diagnostic and research centres to define the phenotypic spectrum and advance understanding of the recurrence risks. Mutations were identified in 38 cases, with the majority being sporadic compound heterozygotes. Eighty-nine DNA sequence changes were identified, including 2 predicted to alter a splice site, 1 predicted to cause a premature stop codon and 13 predicted to cause novel amino acid substitutions. The majority of children had a mutation in the linker region, often 1399G-->A (A467T), and a mutation affecting the polymerase domain. Others had mutations throughout the gene, and 11 had 3 or more substitutions. The clinical presentation ranged from the neonatal period to late adult life, with an overlapping phenotypic spectrum from severe encephalopathy and liver failure to late-onset external ophthalmoplegia, ataxia, myopathy and isolated muscle pain or epilepsy. There was a strong gender bias in children, with evidence of an environmental interaction with sodium valproate. POLG1 mutations cause an overlapping clinical spectrum of disease with both dominant and recessive modes of inheritance. 1399G-->A (A467T) is common in children, but complete POLG1 sequencing is required to identify multiple mutations that can have complex implications for genetic counselling.

Two Dimensional Verification of the Dose Distribution of Gamma Knife Model C using Monte Carlo Simulation with a Virtual Source

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae-Hoon; Kim, Yong-Kyun; Lee, Cheol Ho; Son, Jaebum; Lee, Sangmin; Kim, Dong Geon; Choi, Joonbum; Jang, Jae Yeong [Hanyang University, Seoul (Korea, Republic of); Chung, Hyun-Tai [Seoul National University, Seoul (Korea, Republic of)

2016-10-15

Gamma Knife model C contains 201 {sup 60}Co sources located on a spherical surface, so that each beam is concentrated on the center of the sphere. In the last work, we simulated the Gamma Knife model C through Monte Carlo simulation code using Geant4. Instead of 201 multi-collimation system, we made one single collimation system that collects source parameter passing through the collimator helmet. Using the virtual source, we drastically reduced the simulation time to transport 201 gamma circle beams to the target. Gamma index has been widely used to compare two dose distributions in cancer radiotherapy. Gamma index pass rates were compared in two calculated results using the virtual source method and the original method and measured results obtained using radiocrhomic films. A virtual source method significantly reduces simulation time of a Gamma Knife Model C and provides equivalent absorbed dose distributions as that of the original method showing Gamma Index pass rate close to 100% under 1mm/3% criteria. On the other hand, it gives a little narrow dose distribution compared to the film measurement showing Gamma Index pass rate of 94%. More accurate and sophisticated examination on the accuracy of the simulation and film measurement is necessary.

Qualification study of LiF flight crystals for the objective crystal spectrometer on the SPECTRUM-X-GAMMA satellite

DEFF Research Database (Denmark)

Christensen, Finn Erland; Rasmussen, I.; Schnopper, Herbert W.

1992-01-01

The Objective Crystal Spectrometer (OXS) on the SPECTRUM-X-GAMMA satellite will carry these types of natural crystals LiF(220), Ge(111) and RAP(001). They will be used to study, among others, the H- and the He-like emission from the cosmically important elements Fe, S, Ar and O. More than 300 Li...

Simulation on a limited angle beam gamma ray tomography

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Bum; Jung, Sung Hee; Moon, Jin Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-10-15

Limited angle beam tomography was introduced in the medical field more than two decades ago, where it was mainly used for cardiovascular diagnostics. Later, it was also used to trace multiphase flows. In these studies, the detection systems were fixed and a scanning electron beam was rapidly swept across an xray target using deflection coils. Thus very fast scanning was possible in these studies, but their geometry resulted in a heavy and bulky system because of a complex control system and vacuum tube. Because of its heavy hardware, limited angle beam tomography has remained as indoor equipment. If the source section is replaced by a gamma ray source, limited angle beam tomography will have a very light source device. In addition, limited angle beam tomography with a gamma ray source can be designed using an open type portable gantry because it does not need a vacuum guide for an electron beam. There is a lot of need for a portable tomographic system but so far no definitive solution has been created. The inspection of industrial on-line pipes, wood telephone poles, and cultural assets are some application areas. This study introduces limited angle beam gamma ray tomography, its simulation, and image reconstruction results. Image reconstruction was performed on the virtual experimental data from a Monte Carlo simulation. Image reconstruction algorithms that are known to be useful for limited angle data were applied and their results compared

A Standalone Vision Impairments Simulator for Java Swing Applications

Science.gov (United States)

Oikonomou, Theofanis; Votis, Konstantinos; Korn, Peter; Tzovaras, Dimitrios; Likothanasis, Spriridon

A lot of work has been done lately in an attempt to assess accessibility. For the case of web rich-client applications several tools exist that simulate how a vision impaired or colour-blind person would perceive this content. In this work we propose a simulation tool for non-web JavaTM Swing applications. Developers and designers face a real challenge when creating software that has to cope with a lot of interaction situations, as well as specific directives for ensuring an accessible interaction. The proposed standalone tool will assist them to explore user-centered design and important accessibility issues for their JavaTM Swing implementations.

BioPortal: enhanced functionality via new Web services from the National Center for Biomedical Ontology to access and use ontologies in software applications.

Science.gov (United States)

Whetzel, Patricia L; Noy, Natalya F; Shah, Nigam H; Alexander, Paul R; Nyulas, Csongor; Tudorache, Tania; Musen, Mark A

2011-07-01

The National Center for Biomedical Ontology (NCBO) is one of the National Centers for Biomedical Computing funded under the NIH Roadmap Initiative. Contributing to the national computing infrastructure, NCBO has developed BioPortal, a web portal that provides access to a library of biomedical ontologies and terminologies (http://bioportal.bioontology.org) via the NCBO Web services. BioPortal enables community participation in the evaluation and evolution of ontology content by providing features to add mappings between terms, to add comments linked to specific ontology terms and to provide ontology reviews. The NCBO Web services (http://www.bioontology.org/wiki/index.php/NCBO_REST_services) enable this functionality and provide a uniform mechanism to access ontologies from a variety of knowledge representation formats, such as Web Ontology Language (OWL) and Open Biological and Biomedical Ontologies (OBO) format. The Web services provide multi-layered access to the ontology content, from getting all terms in an ontology to retrieving metadata about a term. Users can easily incorporate the NCBO Web services into software applications to generate semantically aware applications and to facilitate structured data collection.

Altered modulation of gamma oscillation frequency by speed of visual motion in children with autism spectrum disorders.

Science.gov (United States)

Stroganova, Tatiana A; Butorina, Anna V; Sysoeva, Olga V; Prokofyev, Andrey O; Nikolaeva, Anastasia Yu; Tsetlin, Marina M; Orekhova, Elena V

2015-01-01

Recent studies link autism spectrum disorders (ASD) with an altered balance between excitation and inhibition (E/I balance) in cortical networks. The brain oscillations in high gamma-band (50-120 Hz) are sensitive to the E/I balance and may appear useful biomarkers of certain ASD subtypes. The frequency of gamma oscillations is mediated by level of excitation of the fast-spiking inhibitory basket cells recruited by increasing strength of excitatory input. Therefore, the experimental manipulations affecting gamma frequency may throw light on inhibitory networks dysfunction in ASD. Here, we used magnetoencephalography (MEG) to investigate modulation of visual gamma oscillation frequency by speed of drifting annular gratings (1.2, 3.6, 6.0 °/s) in 21 boys with ASD and 26 typically developing boys aged 7-15 years. Multitaper method was used for analysis of spectra of gamma power change upon stimulus presentation and permutation test was applied for statistical comparisons. We also assessed in our participants visual orientation discrimination thresholds, which are thought to depend on excitability of inhibitory networks in the visual cortex. Although frequency of the oscillatory gamma response increased with increasing velocity of visual motion in both groups of participants, the velocity effect was reduced in a substantial proportion of children with ASD. The range of velocity-related gamma frequency modulation correlated inversely with the ability to discriminate oblique line orientation in the ASD group, while no such correlation has been observed in the group of typically developing participants. Our findings suggest that abnormal velocity-related gamma frequency modulation in ASD may constitute a potential biomarker for reduced excitability of fast-spiking inhibitory neurons in a subset of children with ASD.

EVIDENCE FOR ENHANCED {sup 3}HE IN FLARE-ACCELERATED PARTICLES BASED ON NEW CALCULATIONS OF THE GAMMA-RAY LINE SPECTRUM

Energy Technology Data Exchange (ETDEWEB)

Murphy, R. J. [Code 7650, Naval Research Laboratory, Washington, DC 20375 (United States); Kozlovsky, B. [Tel Aviv University, Tel Aviv (Israel); Share, G. H., E-mail: murphy@ssd5.nrl.navy.mil, E-mail: benz@wise.tau.ac.il, E-mail: share@astro.umd.edu [University of Maryland, College Park, MD 20742 (United States)

2016-12-20

The {sup 3}He abundance in impulsive solar energetic particle (SEP) events is enhanced up to several orders of magnitude compared to its photospheric value of [{sup 3}He]/[{sup 4}He] = 1–3 × 10{sup −4}. Interplanetary magnetic field and timing observations suggest that these events are related to solar flares. Observations of {sup 3}He in flare-accelerated ions would clarify the relationship between these two phenomena. Energetic {sup 3}He interactions in the solar atmosphere produce gamma-ray nuclear-deexcitation lines, both lines that are also produced by protons and α particles and lines that are essentially unique to {sup 3}He. Gamma-ray spectroscopy can, therefore, reveal enhanced levels of accelerated {sup 3}He. In this paper, we identify all significant deexcitation lines produced by {sup 3}He interactions in the solar atmosphere. We evaluate their production cross sections and incorporate them into our nuclear deexcitation-line code. We find that enhanced {sup 3}He can affect the entire gamma-ray spectrum. We identify gamma-ray line features for which the yield ratios depend dramatically on the {sup 3}He abundance. We determine the accelerated {sup 3}He/ α ratio by comparing these ratios with flux ratios measured previously from the gamma-ray spectrum obtained by summing the 19 strongest flares observed with the Solar Maximum Mission Gamma-Ray Spectrometer. All six flux ratios investigated show enhanced {sup 3}He, confirming earlier suggestions. The {sup 3}He/ α weighted mean of these new measurements ranges from 0.05 to 0.3 (depending on the assumed accelerated α /proton ratio) and has a <1 × 10{sup −3} probability of being consistent with the photospheric value. With the improved code, we can now exploit the full potential of gamma-ray spectroscopy to establish the relationship between flare-accelerated ions and {sup 3}He-rich SEPs.

Video Game Access, Parental Rules, and Problem Behavior: A Study of Boys with Autism Spectrum Disorder

Science.gov (United States)

Engelhardt, Christopher R.; Mazurek, Micah O.

2014-01-01

Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to…

Monte Carlo simulation of the Leksell Gamma Knife: I. Source modelling and calculations in homogeneous media

Energy Technology Data Exchange (ETDEWEB)

Moskvin, Vadim [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)]. E-mail: vmoskvin@iupui.edu; DesRosiers, Colleen; Papiez, Lech; Timmerman, Robert; Randall, Marcus; DesRosiers, Paul [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

2002-06-21

The Monte Carlo code PENELOPE has been used to simulate photon flux from the Leksell Gamma Knife, a precision method for treating intracranial lesions. Radiation from a single {sup 60}Co assembly traversing the collimator system was simulated, and phase space distributions at the output surface of the helmet for photons and electrons were calculated. The characteristics describing the emitted final beam were used to build a two-stage Monte Carlo simulation of irradiation of a target. A dose field inside a standard spherical polystyrene phantom, usually used for Gamma Knife dosimetry, has been computed and compared with experimental results, with calculations performed by other authors with the use of the EGS4 Monte Carlo code, and data provided by the treatment planning system Gamma Plan. Good agreement was found between these data and results of simulations in homogeneous media. Owing to this established accuracy, PENELOPE is suitable for simulating problems relevant to stereotactic radiosurgery. (author)

A new optical transmission spectrum of WASP-43b from ACCESS

Science.gov (United States)

Weaver, Ian; University of Arizona, Católica, Carnegie

2018-01-01

We present a new ground-based optical transmission spectrum of the Hot Jupiter WASP--43b obtained with the Inamori-Magellan Areal Camera and Spectrograph (IMACS) on the Baade Telescope at Las Campanas Observatory. These observations were made as part of the Arizona-CfA-Catolica+Carnegie Exoplanet Spectroscopy Survey (ACCESS), which aims at providing a uniform, large sample of visible transmission spectra of gaseous exoplanets that will become key in the era of JWST and comparative exoplanetology. Using multi-object differential spectrophotometry, we produce a high precision spectrum of this planet between 400 and 900 nm, combining three different transit epochs. In this analysis, we search for signals of Na I, H-alpha, and K I, as well as for the presence of hazes/clouds.

Gamma ray lines from a universal extra dimension

Energy Technology Data Exchange (ETDEWEB)

Bertone, Gianfranco; Jackson, C. B.; Shaughnessy, Gabe; Tait, Tim M.P.; Vallinotto, Alberto

2012-03-01

Indirect Dark Matter searches are based on the observation of secondary particles produced by the annihilation or decay of Dark Matter. Among them, gamma-rays are perhaps the most promising messengers, as they do not suffer deflection or absorption on Galactic scales, so their observation would directly reveal the position and the energy spectrum of the emitting source. Here, we study the detailed gamma-ray energy spectrum of Kaluza--Klein Dark Matter in a theory with 5 Universal Extra Dimensions. We focus in particular on the two body annihilation of Dark Matter particles into a photon and another particle, which produces monochromatic photons, resulting in a line in the energy spectrum of gamma rays. Previous calculations in the context of the five dimensional UED model have computed the line signal from annihilations into \\gamma \\gamma, but we extend these results to include \\gamma Z and \\gamma H final states. We find that these spectral lines are subdominant compared to the predicted \\gamma \\gamma signal, but they would be important as follow-up signals in the event of the observation of the \\gamma \\gamma line, in order to distinguish the 5d UED model from other theoretical scenarios.

WCGM. A gamma-spectrum analysis program rewritten in Windows

International Nuclear Information System (INIS)

Szekely, G.

2009-01-01

Complete text of publication follows. Introduction The original code was written in Fortran in 1985 and it worked mostly in batch mode. Later the code was redesigned in Pascal and several graphics tools were added. This version (called PGM) is still used, but the limits of MSDOS (memory, graphics, filename length, etc.) make it more and more obsolete. Because of these reasons the redesign of the code is started in order to be able to use it on the most frequently used operating systems, which are nowadays Windows XP and Windows 7. This paper describes the present state of this work and shows some new ways of the usage of the code. In the same time it invites the reader to visit the home page of the code in order to contribute to the further development. Data input Probably one of the main reasons why the original DOS code is still used is that a lot of input formats are accepted. The following short names identify the currently available input spectrum formats: 'ASCII', 'Binary', 'I-format', 'Jyvaeskylae', 'K-format', 'MCA', 'MCAtxt', 'MSI', 'NBI', 'Ortec', 'Oxford/ Nucleus', 'PCA9', 'Tukan'. The most simple ones (ASCII, Binary) contain only the counts of the gamma spectrum, but the more sophisticated ones (I-format, Tukan) also include data for the energy, resolution and efficiency calibrations. The user can choose different levels of interaction during the input process. One can put everything to a control data file and tell the code to use it, or one can manually find the input spectrum and the calibration data during running the code. Spectrum processing After reading the input data the whole spectrum is shown in the main window. To find the peak positions one can use 'Process| Automatic peak search' menu item to scan the displayed interval of the spectrum and assign the peaks with black vertical lines, which were selected by the built-in algorithm. Then the user can fine tune this peak set by manually insert or remove peaks, with the help of the right hand

Energy spectrum of extragalactic gamma-ray sources

Science.gov (United States)

Protheroe, R. J.

1985-01-01

The result of Monte Carlo electron photon cascade calculations for propagation of gamma rays through regions of extragalactic space containing no magnetic field are given. These calculations then provide upper limits to the expected flux from extragalactic sources. Since gamma rays in the 10 to the 14th power eV to 10 to the 17th power eV energy range are of interest, interactions of electrons and photons with the 3 K microwave background radiation are considered. To obtain an upper limit to the expected gamma ray flux from sources, the intergalactic field is assumed to be so low that it can be ignored. Interactions with photons of the near-infrared background radiation are not considered here although these will have important implications for gamma rays below 10 to the 14th power eV if the near infrared background radiation is universal. Interaction lengths of electrons and photons in the microwave background radiation at a temperature of 2.96 K were calculated and are given.

Natural background gamma-ray spectrum. List of gamma-rays ordered in energy from natural radionuclides

Energy Technology Data Exchange (ETDEWEB)

Ichimiya, Tsutomu [Japan Radioisotope Association, Tokyo (Japan); Narita, Tsutomu; Kitao, Kensuke

1998-03-01

A quick index to {gamma}-rays and X-rays from natural radionuclides is presented. In the list, {gamma}-rays are arranged in order of increasing energy. The list also contains {gamma}-rays from radioactive nuclides produced in a germanium detector and its surrounding materials by interaction with cosmic neutrons, as well as direct {gamma}-rays from interaction with the neutrons. Artificial radioactive nuclides emitting {gamma}-rays with same or near energy value as that of the natural {gamma}-rays and X-rays are also listed. In appendix, {gamma}-ray spectra from a rock, uranium ore, thorium, monazite and uraninite and also background spectra obtained with germanium detectors placed in iron or lead shield have been given. The list is designed for use in {gamma}-ray spectroscopy under the conditions of highly natural background, such as in-situ environmental radiation monitoring or low-level activity measurements, with a germanium detector. (author)

Advancing the Implementation of Hydrologic Models as Web-based Applications

Science.gov (United States)

Dahal, P.; Tarboton, D. G.; Castronova, A. M.

2017-12-01

Advanced computer simulations are required to understand hydrologic phenomenon such as rainfall-runoff response, groundwater hydrology, snow hydrology, etc. Building a hydrologic model instance to simulate a watershed requires investment in data (diverse geospatial datasets such as terrain, soil) and computer resources, typically demands a wide skill set from the analyst, and the workflow involved is often difficult to reproduce. This work introduces a web-based prototype infrastructure in the form of a web application that provides researchers with easy to use access to complete hydrological modeling functionality. This includes creating the necessary geospatial and forcing data, preparing input files for a model by applying complex data preprocessing, running the model for a user defined watershed, and saving the results to a web repository. The open source Tethys Platform was used to develop the web app front-end Graphical User Interface (GUI). We used HydroDS, a webservice that provides data preparation processing capability to support backend computations used by the app. Results are saved in HydroShare, a hydrologic information system that supports the sharing of hydrologic data, model and analysis tools. The TOPographic Kinematic APproximation and Integration (TOPKAPI) model served as the example for which we developed a complete hydrologic modeling service to demonstrate the approach. The final product is a complete modeling system accessible through the web to create input files, and run the TOPKAPI hydrologic model for a watershed of interest. We are investigating similar functionality for the preparation of input to Regional Hydro-Ecological Simulation System (RHESSys). Key Words: hydrologic modeling, web services, hydrologic information system, HydroShare, HydroDS, Tethys Platform

Optimization Model for Web Based Multimodal Interactive Simulations.

Science.gov (United States)

Halic, Tansel; Ahn, Woojin; De, Suvranu

2015-07-15

This paper presents a technique for optimizing the performance of web based multimodal interactive simulations. For such applications where visual quality and the performance of simulations directly influence user experience, overloading of hardware resources may result in unsatisfactory reduction in the quality of the simulation and user satisfaction. However, optimization of simulation performance on individual hardware platforms is not practical. Hence, we present a mixed integer programming model to optimize the performance of graphical rendering and simulation performance while satisfying application specific constraints. Our approach includes three distinct phases: identification, optimization and update . In the identification phase, the computing and rendering capabilities of the client device are evaluated using an exploratory proxy code. This data is utilized in conjunction with user specified design requirements in the optimization phase to ensure best possible computational resource allocation. The optimum solution is used for rendering (e.g. texture size, canvas resolution) and simulation parameters (e.g. simulation domain) in the update phase. Test results are presented on multiple hardware platforms with diverse computing and graphics capabilities to demonstrate the effectiveness of our approach.

Design of GNSS Performance Analysis and Simulation Tools as a Web Portal

Directory of Open Access Journals (Sweden)

S. Tadic

2014-11-01

Full Text Available This paper considers design of a web-portal for the validation of behavior of GNSS applications in different environments. The tool provides the positioning performance analysis and a comparison to benchmark devices. Web-portal incorporates a 3D synthetic data generator to compute the propagation and the reception of radio-navigation signals in a 3D virtual environment. This radio propagation simulator uses ray-tracing to calculate interactions between the GNSS signal and the local environment. For faster execution on a GPU platform, the simulator uses BVH optimization. The work is verified in field trials and by using reference software.

Development of low level 226Ra analysis for live fish using gamma-ray spectrometry

Science.gov (United States)

Chandani, Z.; Prestwich, W. V.; Byun, S. H.

2017-06-01

A low level 226Ra analysis method for live fish was developed using a 4π NaI(Tl) gamma-ray spectrometer. In order to find out the best algorithm for accomplishing the lowest detection limit, the gamma-ray spectrum from a 226Ra point was collected and nine different methods were attempted for spectral analysis. The lowest detection limit of 0.99 Bq for an hour counting occurred when the spectrum was integrated in the energy region of 50-2520 keV. To extend 226Ra analysis to live fish, a Monte Carlo simulation model with a cylindrical fish in a water container was built using the MCNP code. From simulation results, the spatial distribution of the efficiency and the efficiency correction factor for the live fish model were determined. The MCNP model will be able to be conveniently modified when a different fish or container geometry is employed as fish grow up in real experiments.

GEANT4 simulation study of a gamma-ray detector for neutron resonance densitometry

International Nuclear Information System (INIS)

Tsuchiya, Harufumi; Harada, Hideo; Koizumi, Mitsuo; Kitatani, Fumito; Takamine, Jun; Kureta, Masatoshi; Iimura, Hideki

2013-01-01

A design study of a gamma-ray detector for neutron resonance densitometry was made with GEANT4. The neutron resonance densitometry, combining neutron resonance transmission analysis and neutron resonance capture analysis, is a non-destructive technique to measure amounts of nuclear materials in melted fuels of the Fukushima Daiichi nuclear power plants. In order to effectively quantify impurities in the melted fuels via prompt gamma-ray measurements, a gamma-ray detector for the neutron resonance densitometry consists of cylindrical and well type LaBr 3 scintillators. The present simulation showed that the proposed gamma-ray detector suffices to clearly detect the gamma rays emitted by 10 B(n, αγ) reaction in a high environmental background due to 137 Cs radioactivity with its Compton edge suppressed at a considerably small level. (author)

Rigidity spectrum of Forbush decrease

International Nuclear Information System (INIS)

Sakakibara, S.; Munakata, K.; Nagashima, K.

1985-01-01

Using data from neutron monitors and muon telescopes at surface and underground stations, the average rigidity spectrum of Forbush decreases (Fds) during the period of 1978-1982 were obtained. Thirty eight Ed-events are classified into two groups, Hard Fd and Soft FD according to size of Fd at the Sakashita station. It is found that a spectral form of a fractional-power type (P to the-gamma sub 1 (P+P sub c) to the -gamma sub2) is more suitable than that of a power-exponential type or of a power type with an upper limiting rigidity. The best fitted spectrum of the fractional-power type is expressed by gamma sub1 = 0.37, gamma sub2 = 0.89 and P subc = 10 GV for Hard Fd and gamma sub1 = 0.77, gamma sub2 = 1.02 and P sub c - 14GV for Soft Fd

Application of Monte Carlo method in determination of air absorbed rate from a full γ-ray spectrum

International Nuclear Information System (INIS)

Zhang Jiangyun; Huang Ning; Tang Lili; Liu Yanfang; Zhang Guanghua

2011-01-01

The dosimetric properties of a gamma-radiation field can be measured by a dose-rate meter or by a gamma-spectrometer with spectrum-dose conversion. One of the spectrum dose conversion methods is to evaluate the radiation dose directly from integrating the observed pulse height spectrum weighted by a G(E) function, instead of making spectrum analysis.In this paper,energy spectra of 11 single energy point sources in 0.1-2.5 MeV are simulated by using Monte Carlo software MCNP5 for NaI(Tl) detectors of Φ 75 mm x 75 mm, Φ 50 mm x 50 mm and Φ 25 mm x 25 mm. The energy spectra are used as standard spectrum to calculate the G(E) value, so as to calculate corresponding doses. Comparing the results with theoretical value,the error is less than 1.5%. Finally, the G(E)-based γ dose rate of radiation field agreed well (within 5%) with the dose rate measured by a dosimeter. (authors)

Monte Carlo simulation of determining porosity by using dual gamma detectors

International Nuclear Information System (INIS)

Zhang Feng; Liu Juntao; Yu Huawei; Yuan Chao; Jia Yan

2013-01-01

Current formation elements spectroscopy logging technology utilize 241 Am-Be neutron source and single BGO detector to determine elements contents. It plays an important role in mineral analysis and lithology identification of unconventional oil and gas exploration, but information measured is relatively ld. Measured system based on 241 Am-Be neutron and dual detectors can be developed to realize the measurement of elements content as well as determine neutron gamma porosity by using ratio of gamma count between near and far detectors. Calculation model is built by Monte Carlo method to study neutron gamma porosity logging response with different spacing and shields. And it is concluded that measuring neutron gamma have high counts and good statistical property contrasted with measuring thermal neutron, but the sensitivity of porosity decrease. Sensitivity of porosity will increase as the spacing of dual detector increases. Spacing of far and near detectors should be around 62 cm and 35 cm respectively. Gamma counts decrease and neutron gamma porosity sensitivity increase when shield is fixed between neutron and detector. The length of main shield should be greater than 10 cm and associated shielding is about 5 cm. By Monte Carlo Simulation study, the result provides technical support for determining porosity in formation elements spectroscopy logging using 241 Am-Be neutron and gamma detectors. (authors)

Production of 16N and obtaining of its gamma spectrum in order to calibrate detectors or determination of fluorine in geological specimens

International Nuclear Information System (INIS)

Rey-Ronco, M.A.; Alonso-Sanchez, T.; Castro-Garcia, M.P.

2010-01-01

In this paper, we show a procedure for producing 16 N and a method to obtain its gamma spectrum with a NaI(Tl) detector. We also demonstrate the interest of this radioactive element for the purpose of NaI(Tl) detector calibration and for the determination of fluorine in geological specimens using an Alpha Beryllium neutron source. This work consists of a theoretical study which analyzes the characteristics of 16 N and nuclear reactions that originate from an Americium Beryllium source of 1Ci activity. We justify our choice of reaction 19 F(n,α) 16 N and the use of fluorspar as a source of fluorine. The mathematical procedure followed to obtain the gamma rays spectrum produced by 16 N in a NaI(Tl) detector is shown.

WebVR: an interactive web browser for virtual environments

Science.gov (United States)

Barsoum, Emad; Kuester, Falko

2005-03-01

The pervasive nature of web-based content has lead to the development of applications and user interfaces that port between a broad range of operating systems and databases, while providing intuitive access to static and time-varying information. However, the integration of this vast resource into virtual environments has remained elusive. In this paper we present an implementation of a 3D Web Browser (WebVR) that enables the user to search the internet for arbitrary information and to seamlessly augment this information into virtual environments. WebVR provides access to the standard data input and query mechanisms offered by conventional web browsers, with the difference that it generates active texture-skins of the web contents that can be mapped onto arbitrary surfaces within the environment. Once mapped, the corresponding texture functions as a fully integrated web-browser that will respond to traditional events such as the selection of links or text input. As a result, any surface within the environment can be turned into a web-enabled resource that provides access to user-definable data. In order to leverage from the continuous advancement of browser technology and to support both static as well as streamed content, WebVR uses ActiveX controls to extract the desired texture skin from industry strength browsers, providing a unique mechanism for data fusion and extensibility.

Intelligent Access to Sequence and Structure Databases (IASSD) - an interface for accessing information from major web databases.

Science.gov (United States)

Ganguli, Sayak; Gupta, Manoj Kumar; Basu, Protip; Banik, Rahul; Singh, Pankaj Kumar; Vishal, Vineet; Bera, Abhisek Ranjan; Chakraborty, Hirak Jyoti; Das, Sasti Gopal

2014-01-01

With the advent of age of big data and advances in high throughput technology accessing data has become one of the most important step in the entire knowledge discovery process. Most users are not able to decipher the query result that is obtained when non specific keywords or a combination of keywords are used. Intelligent access to sequence and structure databases (IASSD) is a desktop application for windows operating system. It is written in Java and utilizes the web service description language (wsdl) files and Jar files of E-utilities of various databases such as National Centre for Biotechnology Information (NCBI) and Protein Data Bank (PDB). Apart from that IASSD allows the user to view protein structure using a JMOL application which supports conditional editing. The Jar file is freely available through e-mail from the corresponding author.

Penerapan Bahasa Alami Sederhana pada Online Public Access Catalog (Opac) Berbasis Web Semantik

OpenAIRE

Andri, Andri

2012-01-01

Online Public Access Catalog (OPAC) merupakan sistem katalog online yang memanfaatkan teknologi komputer dan internet sebagai media pengaksesan dan penyimpanan datanya. Sebuah katalog biasanya memberikan informasi mengenai koleksi yang disimpan dalam sebuah perpustakaan digital. Dalam penelitian ini akan dibuat sebuah prototipe aplikasi pencarian pada katalog online di perpustakaan Universitas Binadarma Palembang berbasis teknologi web semantik serta menerapkan pengolahan bahasa alami sederha...

Evaluation of a Web-Based Professional Development Program (Project ACE) for Teachers of Children with Autism Spectrum Disorders

Science.gov (United States)

Rakap, Salih; Jones, Hazel A.; Emery, Alice Kaye

2015-01-01

This article describes the development, implementation, and second-year evaluation of Project Autism Competencies for Endorsement (ACE), a web-based professional development (PD) program that is designed to train teachers currently working in the field to meet the unique and diverse needs of children with autism spectrum disorders (ASDs). A…

Visibilidad y accesibilidad web de las tesinas de licenciatura en Bibliotecología y Documentación en la Argentina = Web Visibility and Accessibility of Theses in Library Science and Documentation in Argentina

Directory of Open Access Journals (Sweden)

Sandra Gisela Martín

2013-06-01

Full Text Available Se busca describir la visibilidad y accesibilidad web de la investigación en Bibliotecología y Documentación en la Argentina mediante el estudio de las tesinas presentadas para optar al título de licenciatura. Constituye un estudio exploratorio descriptivo con enfoque cuantitativo donde se investiga la visibilidad de tesinas en catálogos y repositorios institucionales, la cantidad de tesinas visibles en la web /cantidad de tesinas accesibles en texto completo, los metadatos de los registros en los catálogos, los metadatos de los registros en los repositorios, la producción de tesinas por año según visibilidad web, la cantidad de autores por tesina según visibilidad web y la distribución temática del contenido de las tesinas. Se concluye que la producción científica de tesinas en Bibliotecología en la Argentina está muy dispersa en la web y que la visibilidad y accesibilidad a las mismas es muy escasa = It describes the web visibility and accessibility of research in library and documentation in Argentina by studying dissertations submitted to qualify for the bachelor's degree. It is an exploratory study with quantitative approach where the visibility of theses in catalogs and institutional repositories, the number of theses visible on the web/amount accessible in full text, metadata records in catalogs, metadata records in the repositories, the production of dissertations per year according to web visibility, the number of authors per dissertation as web visibility and thematic distribution of the content of dissertations. It is concluded that the production of dissertations in library science in Argentina is spread on the web and that the visibility and accessibility of these is very low.

Web-based discovery, access and analysis tools for the provision of different data sources like remote sensing products and climate data

Science.gov (United States)

Eberle, J.; Hese, S.; Schmullius, C.

2012-12-01

To provide different of Earth Observation products in the area of Siberia, the Siberian Earth System Science Cluster (SIB-ESS-C) was established as a spatial data infrastructure at the University of Jena (Germany), Department for Earth Observation. The infrastructure implements standards published by the Open Geospatial Consortium (OGC) and the International Organization for Standardization (ISO) for data discovery, data access and data analysis. The objective of SIB-ESS-C is to faciliate environmental research and Earth system science in Siberia. Several products from the Moderate Resolution Imaging Spectroradiometer sensor were integrated by serving ISO-compliant Metadata and providing OGC-compliant Web Map Service for data visualization and Web Coverage Services / Web Feature Service for data access. Furthermore climate data from the World Meteorological Organization were downloaded, converted, provided as OGC Sensor Observation Service. Each climate data station is described with ISO-compliant Metadata. All these datasets from multiple sources are provided within the SIB-ESS-C infrastructure (figure 1). Furthermore an automatic workflow integrates updates of these datasets daily. The brokering approach within the SIB-ESS-C system is to collect data from different sources, convert the data into common data formats, if necessary, and provide them with standardized Web services. Additional tools are made available within the SIB-ESS-C Geoportal for an easy access to download and analysis functions (figure 2). The data can be visualized, accessed and analysed with this Geoportal. Providing OGC-compliant services the data can also be accessed with other OGC-compliant clients.; Figure 1. Technical Concept of SIB-ESS-C providing different data sources ; Figure 2. Screenshot of the web-based SIB-ESS-C system.

Simulators of tray distillation columns as tools for interpreting gamma-ray scan profile signal

International Nuclear Information System (INIS)

Offei-Mensah, P.S.; Gbadago, J.K.; Dagadu, C.P.K.; Danso, K.A.

2008-01-01

Simulators of tray distillation columns were used to provide technical guidelines for interpreting signals from gamma ray scans used for analysing malfunctions in distillation columns. The transmitted radiation intensities at 0.05 m intervals were determined from top to bottom of simulators of tray distillation columns exposed to 20 mCi of '1'3'7 Cs. Signals generated from the simulators were identical with the experimental signals obtained from the stabilizer column of the crude oil distillation unit at the Tema Oil Refinery Ghana Limited. Changes in the signal level were observed with changes in diameter, type of material (gasoline, air, debris, steel) and orientation of scan line. The analysis provided accurate interpretation of gamma scan profiles. (au)

X-ray echoes from gamma-ray bursts

International Nuclear Information System (INIS)

Dermer, C.D.; Hurley, K.C.; Hartmann, D.H.

1991-01-01

The identification of an echo of reflected radiation in time histories of gamma-ray burst spectra can provide important information about the existence of binary companions or accretion disks in gamma-ray burst systems. Because of the nature of Compton scattering, the spectrum of the echo will be attenuated at gamma-ray energies compared with the spectrum of the primary burst emission. The expected temporal and spectral signatures of the echo and a search for such echoes are described, and implications for gamma-ray burst models are discussed. 35 refs

Monte Carlo simulations towards semi-quantitative prompt gamma activation imaging

International Nuclear Information System (INIS)

Kis, Zoltan; Belgya, Tamas; Szentmiklosi, Laszlo

2011-01-01

Numerous non-destructive techniques utilize neutron attenuation, scattering or capture to gain morphological, structural or elemental information about the material under study. However, few attempts have been made so far to use neutron-induced gamma radiation for 3D element mapping. The first ever facility using direct scanning for element imaging was set up at the Budapest Research Reactor. It was shown that the position-sensitive prompt-gamma detection (PGAI) enables us to determine the spatial distribution of major elements. Iterative Monte Carlo simulation technique has also been developed to provide not only qualitative but also semi-quantitative element distribution of a simple object.

A Web-Based Development Environment for Collaborative Data Analysis

CERN Document Server

Erdmann, M; Glaser, C; Klingebiel, D; Komm, M; Müller, G; Rieger, M; Steggemann, J; Urban, M; Winchen, T

2014-01-01

Visual Physics Analysis (VISPA) is a web-based development environment addressing high energy and astroparticle physics. It covers the entire analysis spectrum from the design and validation phase to the execution of analyses and the visualization of results. VISPA provides a graphical steering of the analysis ow, which consists of self-written, re-usable Python and C++ modules for more demanding tasks. All common operating systems are supported since a standard internet browser is the only software requirement for users. Even access via mobile and touch-compatible devices is possible. In this contribution, we present the most recent developments of our web application concerning technical, state-of-the-art approaches as well as practical experiences. One of the key features is the use of workspaces, i.e. user-congurable connections to remote machines supplying resources and local le access. Thereby, workspaces enable the management of data, computing resources (e.g. remote clusters or computing grids), and a...

Simulation of the spectrum (Co-60), Theratron Equinox, using the code Penelope

International Nuclear Information System (INIS)

Quispe V, N. Y.; Ballon P, C. I.; Vega R, J. L. J.; Santos F, C.

2017-10-01

Using the code Penelope (Penetration and Energy Loss of Positrons and Electrons) V. 2008, the spectrum of the Theratron Equinox cobalt unit, currently used at the Goyeneche Hospital in Arequipa (Peru), was obtained in the radiotherapy service. The Penmain program was used to obtain the spectrum that, together with the PENGEOM package included in the Penelope code, allowed to build complex structures with, in this case, the cobalt unit head essentially comprising the cobalt source and its collimators. The dose-to-depth percentage curves were also obtained in different sizes of irradiated fields of 5 x 5, 10 x 10 and 15 x 15 cm 2 for the cobalt spectrum obtained, in which is observed that there is greater dispersion for fields greater and more time of simulation was needed, being concordance of the results of the simulation, when comparing the experimentally obtained data of the dose with the ionization chamber in a water tank. The spectrum obtained was validated with the data of the ionization chamber in the determination of dose-to-depth percentage curves; it can be used as a reference to optimize the radiotherapy planning system in the simulation with equivalent body materials. (Author)

SB3. Experiment on secondary gamma-ray production cross sections averaged over a fast-neutron spectrum for each of 13 different elements plus a stainless steel

International Nuclear Information System (INIS)

Maerker, R.E.

1976-01-01

The experimental and calculational details for a CSEWG integral data testing shielding experiment are presented. This particular experiment measured the secondary gamma-ray production cross sections averaged over a fast-neutron spectrum for iron, oxygen, sodium, aluminum, copper, titanium, calcium, potassium, silicon, nickel, zinc, barium, sulfur, and a type 321 stainless steel. The gamma-ray production cross sections were binned into 0.5-MeV wide gamma-ray energy intervals. 29 tables, 1 figure

Self-absorption corrections of various sample-detector geometries in gamma-ray spectrometry using sample Monte Carlo Simulations

International Nuclear Information System (INIS)

Ahmad Saat; Appleby, P.G.; Nolan, P.J.

1997-01-01

Corrections for self-absorption in gamma-ray spectrometry have been developed using a simple Monte Carlo simulation technique. The simulation enables the calculation of gamma-ray path lengths in the sample which, using available data, can be used to calculate self-absorption correction factors. The simulation was carried out on three sample geometries: disk, Marinelli beaker, and cylinder (for well-type detectors). Mathematical models and experimental measurements are used to evaluate the simulations. A good agreement of within a few percents was observed. The simulation results are also in good agreement with those reported in the literature. The simulation code was carried out in FORTRAN 90,

Discursive Policy Webs in a Globalisation Era: A Discussion of Access to Professions and Trades for Immigrant Professionals in Ontario, Canada

Science.gov (United States)

Goldberg, Michelle P.

2006-01-01

This article explores the link between discourse and policy using a discursive web metaphor. It develops the notion of policy as a discursive web based on a post-positivist framework that recognises the way multiple discourses from multiple voices interact in a complex web of power relationships to influence reality. Using Ontario's Access to…

Some Programs Should Not Run on Laptops - Providing Programmatic Access to Applications Via Web Services

Science.gov (United States)

Gupta, V.; Gupta, N.; Gupta, S.; Field, E.; Maechling, P.

2003-12-01

hosted these Web Services as a part of the SCEC Community Modeling Environment (SCEC/CME) ITR Project (http://www.scec.org/cme). We have implemented Web Services for several of the reasons sited previously. For example, we implemented a FORTRAN-based Earthquake Rupture Forecast (ERF) as a Web Service for use by client computers that don't support a FORTRAN runtime environment. We implemented a Generic Mapping Tool (GMT) Web Service for use by systems that don't have local access to GMT. We implemented a Hazard Map Calculator Web Service to execute Hazard calculations that are too computationally intensive to run on a local system. We implemented a Coordinate Conversion Web Service to enforce a standard and consistent method for converting between UTM and Lat/Lon. Our experience developing these services indicates both strengths and weakness in current Web Service technology. Client programs that utilize Web Services typically need network access, a significant disadvantage at times. Programs with simple input and output parameters were the easiest to implement as Web Services, while programs with complex parameter-types required a significant amount of additional development. We also noted that Web services are very data-oriented, and adapting object-oriented software into the Web Service model proved problematic. Also, the Web Service approach of converting data types into XML format for network transmission has significant inefficiencies for some data sets.

DoSSiER: Database of Scientific Simulation and Experimental Results

CERN Document Server

Wenzel, Hans; Genser, Krzysztof; Elvira, Daniel; Pokorski, Witold; Carminati, Federico; Konstantinov, Dmitri; Ribon, Alberto; Folger, Gunter; Dotti, Andrea

2017-01-01

The Geant4, GeantV and GENIE collaborations regularly perform validation and regression tests for simulation results. DoSSiER (Database of Scientific Simulation and Experimental Results) is being developed as a central repository to store the simulation results as well as the experimental data used for validation. DoSSiER can be easily accessed via a web application. In addition, a web service allows for programmatic access to the repository to extract records in json or xml exchange formats. In this article, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

Size-based predictions of food web patterns

DEFF Research Database (Denmark)

Zhang, Lai; Hartvig, Martin; Knudsen, Kim

2014-01-01

We employ size-based theoretical arguments to derive simple analytic predictions of ecological patterns and properties of natural communities: size-spectrum exponent, maximum trophic level, and susceptibility to invasive species. The predictions are brought about by assuming that an infinite number...... of species are continuously distributed on a size-trait axis. It is, however, an open question whether such predictions are valid for a food web with a finite number of species embedded in a network structure. We address this question by comparing the size-based predictions to results from dynamic food web...... simulations with varying species richness. To this end, we develop a new size- and trait-based food web model that can be simplified into an analytically solvable size-based model. We confirm existing solutions for the size distribution and derive novel predictions for maximum trophic level and invasion...

Remote Internet access to advanced analytical facilities: a new approach with Web-based services.

Science.gov (United States)

Sherry, N; Qin, J; Fuller, M Suominen; Xie, Y; Mola, O; Bauer, M; McIntyre, N S; Maxwell, D; Liu, D; Matias, E; Armstrong, C

2012-09-04

Over the past decade, the increasing availability of the World Wide Web has held out the possibility that the efficiency of scientific measurements could be enhanced in cases where experiments were being conducted at distant facilities. Examples of early successes have included X-ray diffraction (XRD) experimental measurements of protein crystal structures at synchrotrons and access to scanning electron microscopy (SEM) and NMR facilities by users from institutions that do not possess such advanced capabilities. Experimental control, visual contact, and receipt of results has used some form of X forwarding and/or VNC (virtual network computing) software that transfers the screen image of a server at the experimental site to that of the users' home site. A more recent development is a web services platform called Science Studio that provides teams of scientists with secure links to experiments at one or more advanced research facilities. The software provides a widely distributed team with a set of controls and screens to operate, observe, and record essential parts of the experiment. As well, Science Studio provides high speed network access to computing resources to process the large data sets that are often involved in complex experiments. The simple web browser and the rapid transfer of experimental data to a processing site allow efficient use of the facility and assist decision making during the acquisition of the experimental results. The software provides users with a comprehensive overview and record of all parts of the experimental process. A prototype network is described involving X-ray beamlines at two different synchrotrons and an SEM facility. An online parallel processing facility has been developed that analyzes the data in near-real time using stream processing. Science Studio and can be expanded to include many other analytical applications, providing teams of users with rapid access to processed results along with the means for detailed

Gamma irradiation of cultural artifacts for disinfection using Monte Carlo simulations

International Nuclear Information System (INIS)

Choi, Jong-il; Yoon, Minchul; Kim, Dongho

2012-01-01

In this study, it has been investigated the disinfection of Korean cultural artifacts by gamma irradiation, simulating the absorbed dose distribution on the object with the Monte Carlo methodology. Fungal contamination was identified on two traditional Korean agricultural tools, Hongdukkae and Holtae, which had been stored in a museum. Nine primary species were identified from these items: Bjerkandera adusta, Dothideomycetes sp., Penicillium sp., Cladosporium tenuissimum, Aspergillus versicolor, Penicillium sp., Entrophospora sp., Aspergillus sydowii, and Corynascus sepedonium. However, these fungi were completely inactivated by gamma irradiation at an absorbed dose of 20 kGy on the front side. Monte Carlo N Particle Transport Code was used to simulate the doses applied to these cultural artifacts, and the measured dose distributions were well predicted by the simulations. These results show that irradiation is effective for the disinfection of cultural artifacts and that dose distribution can be predicted with Monte Carlo simulations, allowing the optimization of the radiation treatment. - Highlights: ► Radiation was applied for the disinfection of Korean cultural artifacts. ► Fungi on the artifacts were completely inactivated by the irradiation. ► Monte Carlo N Particle Transport Code was used to predict the dose distribution. ► This study is applicable for the preservation of cultural artifacts by irradiation.

Development and Calibration of the ART-XC Mirror Modules for the Spectrum Rontgen Gamma Mission

Science.gov (United States)

Ramsey, B.; Gubarev, M.; Elsner, R.; Kolodziejczak, J.; Odell, S.; Swartz, D.; Pavlinsky, M.; Tkachenko, A.; Lapshov, I.

2013-01-01

The Spectrum-Röntgen-Gamma (SRG) mission is a Russian-lead X-ray astrophysical observatory that carries two co-aligned X-ray telescope systems. The primary instrument is the German-led extended ROentgen Survey with an Imaging Telescope Array (eROSITA), a 7-module X-ray telescope system that covers the energy range from 0.2-12 keV. The complementary instrument is the Astronomical Roentgen Telescope -- X-ray Concentrator (ART-XC or ART), a 7-module Xray telescope system that provides higher energy coverage, up to 30 keV.

Pulser injection with subsequent removal for gamma-ray spectrometry

International Nuclear Information System (INIS)

Hartwell, J.K.; Goodwin, S.G.; Johnson, L.O.; Killian, E.W.

1990-01-01

This patent describes a module for use with a gamma-ray spectroscopy system. The system includes a gamma-ray detector for detecting gamma-ray events and producing a signal representing the gamma-ray events, a converter responsive to the detector and capable of converting the signal to a spectrum, a storage memory responsive to the converter and capable of storing the spectrum at address locations in memory, and a pulser capable of injecting pulses into the signal produced by the detector. The module comprises: means for generating a logic pulse for controlling the pulser, the controlling means adapted for coupling to the pulser; means for generating separation of events logic to isolate the components of a combined gamma-ray---pulse spectrum, the separation of events logic means adapted for coupling to the converter and the storage memory with the capability of storing pulses at address locations in the storage memory separate from the gamma-ray events; means for receiving an imitating signal from the converter to generate a plurality of operations by the module; means for tracking variations in a gamma-ray---pulse spectrum brought on by external parameter changes; and means for interfacing with commercially developed gamma-ray spectrometry equipment

Exploiting the potential of intranet for managing drug spectrum a web base publication in a Tertiary Care Hospital in Mumbai

Directory of Open Access Journals (Sweden)

Yashashri Chandrakant Shetty

2015-01-01

Full Text Available Objective: The study surveyed the availability of the intranet in campus and also the knowledge related to drug spectrum an intranet publication. Materials and Methods: Institutional ethics committee permission was obtained. Verbal consent was taken from the faculty and resident doctors of departments where all the facilities were available. Universal sampling method was used for recruitment. Pre-validated questionnaires were given to approximately 100 faculty and 500 resident doctors in the year 2012-2013. The questionnaire contained 15 items. Content analysis was done. The study questionnaire focused on a survey to obtain participants feedback on the use of the intranet and to evaluate the use of intranet as a source of knowledge. It also dealt on the relevance of the drug spectrum in the context of their subject. The responses were taken after giving the participants sufficient time. Data was entered into an Excel 2003 spread sheet and analyzed by using descriptive statistics. Results: The total number of respondents who participated in our study was 134 including faculty and residents from various departments. A total of 117 (89.66% respondents stated that their departments have access to the internet. Departments having access to intranet was 103 (76.29%. 67 (49.62% respondents have accessed. 67 (49.62% did not have the time to visit intranet site whereas 67 (49.62% have not accessed intranet. 89 (65.92% respondents were not aware of the drug spectrum. 101 (74.81% respondents felt that drug spectrum is a useful activity on intranet. 45 (33.33% knew about the intranet periodical drug spectrum, but most of the respondents (33.33% explained the meaning of the word drug spectrum according to their understanding, but never knew about the online intranet journal drug spectrum. Conclusion: The study found that the intranet is available in the campus, but it is not being utilized. The awareness and knowledge regarding drug spectrum is lacking, but

A new measurement-while-drilling gamma ray log calibrator

International Nuclear Information System (INIS)

Meisner, J.; Brooks, A.; Wisniewski, W.

1985-01-01

Many of the present methods of calibration for both wireline and MWD gamma ray detectors use a point source at a fixed distance from the detector. MWD calibration errors are introduced from scattering effects, from spectral differences, from position sensitivity and form lack of cylindrical geometry. A new method has been developed at Exploration Logging INc. (EXLOG) that eliminates these errors. The method uses a wrap-around or annular calibrator, referenced to the University of Houston gamma ray API pit. The new calibrator is designed to simulate the API pit's gamma ray emission spectrum with a finite amount of natural source material in the annular shape. Because of the thickness of steel between the MWD gamma ray detector and the formation, there is theoretical necessity for spectral matching. A simple theoretical approach was used to calibrate the new calibrator. Spectral matching allows a closer approximation to wireline logs and makes it possible to estimate the relative spectral content of a formation

Energy Harvesting-based Spectrum Access with Incremental Cooperation, Relay Selection and Hardware Noises

Directory of Open Access Journals (Sweden)

T. N. Nguyen

2017-04-01

Full Text Available In this paper, we propose an energy harvesting (EH-based spectrum access model in cognitive radio (CR network. In the proposed scheme, one of available secondary transmitters (STs helps a primary transmitter (PT forward primary signals to a primary receiver (PR. Via the cooperation, the selected ST finds opportunities to access licensed bands to transmit secondary signals to its intended secondary receiver (SR. Secondary users are assumed to be mobile, hence, optimization of energy consumption for these users is interested. The EH STs have to harvest energy from the PT's radio-frequency (RF signals to serve the PT-PR communication as well as to transmit their signals. The proposed scheme employs incremental relaying technique in which the PR only requires the assistance from the STs when the transmission between PT and PR is not successful. Moreover, we also investigate impact of hardware impairments on performance of the primary and secondary networks. For performance evaluation, we derive exact and lower-bound expressions of outage probability (OP over Rayleigh fading channel. Monte-Carlo simulations are performed to verify the theoretical results. The results present that the outage performance of both networks can be enhanced by increasing the number of the ST-SR pairs. In addition, it is also shown that fraction of time used for EH, positions of the secondary users and the hardware-impairment level significantly impact on the system performance.

World Wide Webs: Crossing the Digital Divide through Promotion of Public Access

Science.gov (United States)

Coetzee, Liezl

“As Bill Gates and Steve Case proclaim the global omnipresence of the Internet, the majority of non-Western nations and 97 per cent of the world's population remain unconnected to the net for lack of money, access, or knowledge. This exclusion of so vast a share of the global population from the Internet sharply contradicts the claims of those who posit the World Wide Web as a ‘universal' medium of egalitarian communication.” (Trend 2001:2)

Influence of Internet Accessibility and Demographic factors on utilization of Web-based Health Information Resources by Resident Doctors in Nigeria.

Science.gov (United States)

Ajuwon, G A; Popoola, S O

2014-09-01

The internet is a huge library with avalanche of information resources including healthcare information. There are numerous studies on use of electronic resources by healthcare providers including medical practitioners however, there is a dearth of information on the patterns of use of web-based health information resource by resident doctors in Nigeria. This study therefore investigates the influence of internet accessibility and demographic factors on utilization of web-based health information resources by resident doctors in tertiary healthcare institutions in Nigeria. Descriptive survey design was adopted for this study. The population of study consisted of medical doctors undergoing residency training in 13 tertiary healthcare institutions in South-West Nigeria. The tertiary healthcare institutions were Federal Medical Centres, University Teaching Hospitals and Specialist Hospitals (Neuropsychiatric and Orthopaedic). A pre-tested, self-administered questionnaire was used for data collection. The Statistical Package for the Social Sciences (SPSS) was used for data analysis. Data were analyzed using descriptive statistics, Pearson Product Moment correlation and multiple regression analysis. The mean age of the respondents was 34 years and males were in the majority (69.0%). A total of 96.1% respondents had access to the Internet. E-mail (X̄=5.40, SD=0.91), Google (X̄=5.26, SD=1.38), Yahoo (X̄=5.15, SD=4.44) were used weekly by the respondents. Preparation for Seminar/Grand Round presentation (X̄=8.4, SD=1.92), research (X̄=7.8, SD=2.70) and communication (X̄=7.6, SD=2.60) were ranked high as purposes for use of web-based information resources. There is a strong, positive and significant relationship between internet accessibility and utilization of web-based health information resources (r=0.628, pdesignation (B=-0.343) educational qualification (B=2.411) significantly influence utilization of web-based health information resources of the respondents. A

A localized cooperative wideband spectrum sensing for dynamic access of TV bands using RF sensor networks

KAUST Repository