Operating Systems (operating + systems)

Distribution by Scientific Domains


Selected Abstracts


Novel software architecture for rapid development of magnetic resonance applications

CONCEPTS IN MAGNETIC RESONANCE, Issue 3 2002
Josef Debbins
Abstract As the pace of clinical magnetic resonance (MR) procedures grows, the need for an MR scanner software platform on which developers can rapidly prototype, validate, and produce product applications becomes paramount. A software architecture has been developed for a commercial MR scanner that employs state of the art software technologies including Java, C++, DICOM, XML, and so forth. This system permits graphical (drag and drop) assembly of applications built on simple processing building blocks, including pulse sequences, a user interface, reconstruction and postprocessing, and database control. The application developer (researcher or commercial) can assemble these building blocks to create custom applications. The developer can also write source code directly to create new building blocks and add these to the collection of components, which can be distributed worldwide over the internet. The application software and its components are developed in Java, which assures platform portability across any host computer that supports a Java Virtual Machine. The downloaded executable portion of the application is executed in compiled C++ code, which assures mission-critical real-time execution during fast MR acquisition and data processing on dedicated embedded hardware that supports C or C++. This combination permits flexible and rapid MR application development across virtually any combination of computer configurations and operating systems, and yet it allows for very high performance execution on actual scanner hardware. Applications, including prescan, are inherently real-time enabled and can be aggregated and customized to form "superapplications," wherein one or more applications work with another to accomplish the clinical objective with a very high transition speed between applications. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 216,237, 2002 [source]


Dynamic load-balancing mechanism for distributed Java applications

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 3 2006
Violeta Felea
Abstract Program environments or operating systems generally leave the decision on the allocation of program entities to the developer, offering either placement directives, or tools available through the manipulation of a graphical interface. These approaches cannot always take into account the dynamic behavior of applications, dynamicity in the execution environment or the heterogeneity of the execution platform. Transparent deployment algorithms are necessary for automizing and optimizing application distribution. The Adaptive Distributed Applications in Java (ADAJ) project deals with placement and migration of Java objects. It automatically deploys parallel Java applications on a cluster of workstations using monitoring information about the application behavior. The transparency obtained through the integration of these tools in the middleware makes such an environment easy to use and improves efficiency. Copyright © 2005 John Wiley & Sons, Ltd. [source]


HLA real-time extension

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2004
Hui Zhao
Abstract The IEEE 1516 Standard ,High Level Architecture (HLA)' and its implementation ,Run-Time Infra-structure (RTI)' defines a general-purpose network communication mechanism for Distributed Interactive Simulation (DIS). However, it does not address real-time requirements of DIS. Current operating system technologies can provide real-time processing through some real-time operating systems (RTOSs) and the Internet is also moving to an age of Quality of Service (QoS), providing delay and jitter bounded services. With the availability of RTOSs and IP QoS, it is possible for HLA to be extended to take advantage of these technologies in order to construct an architecture for Real-Time DIS (RT-DIS). This extension will be a critical aspect of applications in virtual medicine, distributed virtual environments, weapon simulation, aerospace simulation and others. This paper outlines the current real-time technology with respect to operating systems and at the network infrastructure level. After summarizing the requirements and our experiences with RT-DIS, we present a proposal for HLA real-time extension and architecture for real-time RTI. Similar to the growth of real-time CORBA (Common Object Request Broker) after the mature based CORBA standard suite, Real-Time HLA is a natural extension following the standardization of HLA into IEEE 1516 in September 2000. Copyright © 2004 John Wiley & Sons, Ltd. [source]


The J2EE ECperf benchmark results: transient trophies or technology treasures?

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2004
Paul Brebner
Abstract ECperf, the widely recognized industry standard J2EE benchmark, has attracted a large number of results submissions and their subsequent publications. However, ECperf places little restriction on the hardware platforms, operating systems and databases utilized in the benchmarking process. This, combined with the existence of only two primary metrics, makes it difficult to accurately compare the performance of the Application Server products themselves. By mining the full-disclosure archives for trends and correlations, we have discovered that J2EE technology is very scalable both in a scale-up and scale-out manner. Other observed trends include a linear correlation between middle-tier total processing power and throughput, as well as between J2EE Application Server license costs and throughput. However, the results clearly indicate that there is an increasing cost per user with increasing capacity systems and scale-up is proportionately more expensive than scale-out. Finally, the correlation between middle-tier processing power and throughput, combined with results obtained from a different ,lighter-weight' benchmark, facilitates an estimate of throughput for different types of J2EE applications. Copyright © 2004 John Wiley & Sons, Ltd. [source]


The Dialoguer: An Interactive Bilingual Interface to a Network Operating System

EXPERT SYSTEMS, Issue 3 2001
Emad Al-Shawakfa
We have developed a bilingual interface to the Novell network operating system, called the Dialoguer. This system carries on a conversation with the user in Arabic or English or a combination of the two and attempts to help the user use the Novell network operating system. Learning to use an operating system is a major barrier in starting to use computers. There is no single standard for operating systems which makes it difficult for novice users to learn a new operating system. With the proliferation of client,server environments, users will eventually end up using one network operating system or another. These problems motivated our choice of an area to work in and they have made it easy to find real users to test our system. This system is both an expert system and a natural language interface. The system embodies expert knowledge of the operating system commands and of a large variety of plans that the user may want to carry out. The system also contains a natural language understanding component and a response generation component. The Dialoguer makes extensive use of case frame tables in both components. Algorithms for handling a bilingual dialogue are one of the important contributions of this paper along with the Arabic case frames. [source]


xBCI: A Generic Platform for Development of an Online BCI System

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 4 2010
I Putu Susila Non-member
Abstract A generic platform for realizing an online brain,computer interface (BCI) named xBCI was developed. The platform consists of several functional modules (components), such as data acquisition, storage, mathematical operations, signal processing, network communication, data visualization, experiment control, and real-time feedback presentation. Users can easily build their own BCI systems by combining the components on a graphical-user-interface (GUI) based diagram editor. They can also extend the platform by adding components as plug-ins or by creating components using a scripting language. The platform works on multiple operating systems and supports parallel (multi-threaded) data processing and data transfer to other PCs through a network transmission control protocol/internet protocol or user datagram protocol (TCP/IP or UDP). A BCI system based on motor imagery and a steady-state visual evoked potential (SSVEP) based BCI system were constructed and tested on the platform. The results show that the platform is able to process multichannel brain signals in real time. The platform provides users with an easy-to-use system development tool and reduces the time needed to develop a BCI system. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]


Impact of Redhat IPv6 router on heterogeneous host connections

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2007
Sulaiman Syed Mohamed
Abstract Internet's popularity has been expanding on dramatic pace and the number of people getting connected to it multiplies regularly. With this high demand, the current Internet Protocol (IPv4) has reached its limits. The next generation Internet Protocol version6 (IPv6) has been incorporated into various operating systems. The motivation behind this work is how well IPv6 co-operates with various operating systems. The performance of the IP stack, together with the behaviour of the OS greatly affects the efficiency of network applications built on top of it. The acceptance of IPv6 implementations on various operating systems heavily relies on the end-user performance. In this paper, we propose to analyse these various IPv6 implementations for its host and router-level supports. In this paper, we investigate the impact of Redhat-based IPv6 router on IPv6 stacks of three different operating systems namely, Windows2003, Redhat Linux 9.0 (Redhat9.0) and FreeBSD4.9. Copyright © 2006 John Wiley & Sons, Ltd. [source]


IDEA: Interface dynamics and energetics algorithm

JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 15 2007
D. Duca
Abstract IDEA, interface dynamics and energetics algorithm, was implemented, in FORTRAN, under different operating systems to mimic dynamics and energetics of elementary events involved in interfacial processes. The code included a parallel elaboration scheme in which both the stochastic and the deterministic components, involved in the developed physical model, worked simultaneously. IDEA also embodied an optionally running VISUAL subroutine, showing the dynamic energy changes caused by the surface events, e.g., occurring at the gas-solid interface. Monte Carlo and ordinary differential equation system subroutines were employed in a synergistic way to drive the occurrence of the elementary events and to manage the implied energy flows, respectively. Biphase processes, namely isothermal and isobaric adsorption of carbon monoxide on nickel, palladium, and platinum surfaces, were first studied to test the capability of the code in modeling real frames. On the whole, the simulated results showed that IDEA could reproduce the inner characteristics of the studied systems and predict properties not yet experimentally investigated. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007 [source]


Novel methodology for the archiving and interactive reading of clinical magnetic resonance spectroscopic imaging

MAGNETIC RESONANCE IN MEDICINE, Issue 3 2002
Jeffry R. Alger
Abstract Archiving clinical magnetic resonance spectroscopic imaging (MRSI) data and presenting the data to specialists (e.g., neuroradiologists, neurosurgeons, neurologists, neuro-oncologists, and MR scientists) who work in different physical locations is a practical problem of significance. This communication describes a novel solution. The study hypothesis was that it is possible to use widely available distributed computing techniques to create a clinical MRSI user interface addressable from any personal computer with a suitable network connection. A worldwide web MRSI archive and interface system was created that permits the user to interactively view individual MRSI voxel spectra with correlation to MR images and to parametric spectroscopic images. Web browser software (i.e., Netscape and Internet Explorer) permits users in various physical locations to access centrally archived MRSI data using a variety of operating systems and client workstations. The system was used for archiving and displaying more than 1000 clinical MRSI studies performed at the authors' institution. The system also permits MRSI data to be viewed via the Internet from distant locations worldwide. The study illustrates that widely available software operating within highly distributed electronic networks can be used for archiving and interactive reading of large amounts of clinical MRSI data. Magn Reson Med 48:411,418, 2002. © 2002 Wiley-Liss, Inc. [source]


msatcommander: detection of microsatellite repeat arrays and automated, locus-specific primer design

MOLECULAR ECOLOGY RESOURCES, Issue 1 2008
BRANT C. FAIRCLOTH
Abstract msatcommander is a platform-independent program designed to search for microsatellite arrays, design primers, and tag primers using an automated routine. msatcommander accepts as input DNA sequence data in single-sequence or concatenated, fasta -formatted files. Search data and locus-specific primers are written to comma-separated value files for subsequent use in spreadsheet or database programs. Binary versions of the graphical interface for msatcommander are available for Apple OS X and Windows XP. Users of other operating systems may run the graphical interface version using the available source code, provided their environment supports at least Python 2.4, Biopython 1.43, and wxPython 2.8. msatcommander is available from http://code.google.com/p/msatcommander/. [source]


Predicting the Number of Defects Remaining In Operational Software

NAVAL ENGINEERS JOURNAL, Issue 1 2001
P. J. Hartman Ph.D
ABSTRACT Software is becoming increasingly critical to the Fleet as more and more commercial off-the-shelf (COTS) programs are being introduced in operating systems and applications. Program managers need to specify, contract, and manage the development and integration of software for warfare systems, condition based monitoring, propulsion control, parts requisitions, and shipboard administration. The intention here is to describe the state-of-the-art in Software Reliability Engineering (SRE) and defect prediction for commercial and military programs. The information presented here is based on data from the commercial software industry and shipboard program development. The strengths and weaknesses of four failure models are compared using these cases. The Logarithmic Poisson Execution Time (LPET) model best fits the data and satisfied the fundamental principles of reliability theory. The paper presents the procedures for defining software failures, tracking defects, and making spreadsheet predictions of the defects still remaining in the software after it has been deployed. Rules-of-thumb for the number of defects in commercial software and the relative expense required to fix these errors are provided for perspective. [source]


Specific critical concentrations of low dosage hydrate inhibitors in a THF,NaCl hydrate formation solution

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010
Ailin Ding
Abstract Hydrate formation and its attendant problems are well known in the oil and gas industry. The desire to reduce the costs and environmental impact of traditional hydrate inhibitors has led to a focus on the design, development and evaluation of novel and environmentally friendly low dosage hydrate inhibitors (LDHIs). In this study, two LDHIs, namely Luvicap® EG and Gaffix® VC-713, were tested using tetrahydrofuran (THF) as a hydrate promoter and a ball-stop rig. The ball stop-time was used to determine the inhibition efficiency. The concentration effect of inhibitors, salts and solvents on the ball-stop time was investigated. Results indicated that the inhibition efficiency of an inhibitor is sensitive to the micro-environment of the THF-hydrates activities which includes the concentration and types of these additives. The reproducibility and consistency of the test results were also largely dependent on the concentration of inhibitors. Reliable information was provided only if the concentration of the inhibitor was above a critical concentration, below which the testing results scattered drastically and were inconsistent. As the critical concentration was inhibitor-dependent, a specific critical concentration (SCC) was proposed which is the first reported in such investigations. We concluded that the inhibition efficiency of an LDHI should be determined by both the ball-stop time and its SCC. Comparison of ball-stop times between two inhibitors should be made above their SCCs. Salt and solvent concentrations and other additives present in the operating systems should also be considered when a suitable LDHI concentration is determined for a particular field application. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd. [source]