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MultiView : a methodology for supporting multiple view schemata in object-oriented databases
It has been widely recognized that object-oriented database (OODB) technology needs to be extended to provide a mechanism similar to views in relational database systems. We define an object-oriented view to be an arbitrarily complex virtual schema graph with possibly restructured generalization and decomposition hierarchies - rather than just one virtual class as has been proposed in the literature. In this paper, we propose a methodology, called MultiView, for supporting multiple such view schemata. MultiView breaks the schema design task into the following independent and well-defined subtasks: (1) the customization of type descriptions and object sets of existing classes by deriving virtual classes, (2) the integration of all derived classes into one consistent global schema graph, and (3) the definition of arbitrarily complex view schemata on this augmented global schema. For the first task of MultiView, we define a set of object algebra operators that can be used by the view definer for class customization. For the second task of MultiView, we propose an algorithm that automatically integrates these newly derived virtual classes into the global schema. We solve the third task of MultiView by first letting the view definer explicitly select the desired view classes from the global schema using a view definition language and then by automatically generating a view class hierarchy for these selected classes. In addition, we present algorithms that verify the closure property of a view and, if found to be incomplete, transform it into a closed, yet minimal, view. In this paper, we introduce the fundamental concept of view independence and show MultiView to be view independent. We also outline implementation techniques for realizing MultiView with existing OODB technology
Stark Broadening of in III Lines in Astrophysical and Laboratory Plasma
Besides the need of Stark broadening parameters for a number of problems in
physics, and plasma technology, in hot star atmospheres the conditions exist
where Stark widths are comparable and even larger than the thermal Doppler
widths. Using the semiclassical perturbation method we investigated here the
influence of collisions with charged particles for In III spectral lines. We
determined a number of Stark broadening parameters important for the
investigation of plasmas in the atmospheres of A-type stars and white dwarfs.
Also, we have compared the obtained results with existing experimental data.
The results will be included in the STARK-B database, the Virtual Atomic and
Molecular Data Center and the Serbian Virtual Observatory
Виконання розподiлених запитiв у мультибазових сховищах даних з використанням технологiї MapReduce
У данiй доповiдi розглядається питання застосування технологiї MapReduce до проектування мультибазових сховищ даних. Дане рiшення позицiонується як гiбрид використанн архiтектури Virtual Database та технології MapReduce та може бути використано для змiшаного (Iнтернет та Iнтранет) збереження даних.Application of MapReduce technology is considered in this article. This solution is positioned as hybrid use of Virtual Database and MapReduce technologyand can be used for mixed (Internet and Intranet) data storage
The MultiDark Database: Release of the Bolshoi and MultiDark Cosmological Simulations
We present the online MultiDark Database -- a Virtual Observatory-oriented,
relational database for hosting various cosmological simulations. The data is
accessible via an SQL (Structured Query Language) query interface, which also
allows users to directly pose scientific questions, as shown in a number of
examples in this paper. Further examples for the usage of the database are
given in its extensive online documentation (www.multidark.org). The database
is based on the same technology as the Millennium Database, a fact that will
greatly facilitate the usage of both suites of cosmological simulations. The
first release of the MultiDark Database hosts two 8.6 billion particle
cosmological N-body simulations: the Bolshoi (250/h Mpc simulation box, 1/h kpc
resolution) and MultiDark Run1 simulation (MDR1, or BigBolshoi, 1000/h Mpc
simulation box, 7/h kpc resolution). The extraction methods for halos/subhalos
from the raw simulation data, and how this data is structured in the database
are explained in this paper. With the first data release, users get full access
to halo/subhalo catalogs, various profiles of the halos at redshifts z=0-15,
and raw dark matter data for one time-step of the Bolshoi and four time-steps
of the MultiDark simulation. Later releases will also include galaxy mock
catalogs and additional merging trees for both simulations as well as new large
volume simulations with high resolution. This project is further proof of the
viability to store and present complex data using relational database
technology. We encourage other simulators to publish their results in a similar
manner.Comment: 28 pages, 9 figures, submitted to New Astronom
Cross-middleware Interoperability in Distributed Concurrent Engineering
Secure, distributed collaboration between different organizations is a key challenge in Grid computing today. The GDCD project has produced a Grid-based demonstrator Virtual Collaborative Facility (VCF) for the European Space Agency. The purpose of this work is to show the potential of Grid technology to support fully distributed concurrent design, while addressing practical considerations including network security, interoperability, and integration of legacy applications. The VCF allows domain engineers to use the concurrent design methodology in a distributed fashion to perform studies for future space missions. To demonstrate the interoperability and integration capabilities of Grid computing in concurrent design, we developed prototype VCF components based on ESA’s current Excel-based Concurrent Design Facility (a non-distributed environment), using a STEP-compliant database that stores design parameters. The database was exposed as a secure GRIA 5.1 Grid service, whilst a .NET/WSE3.0-based library was developed to enable secure communication between the Excel client and STEP database
Data mining technology for the evaluation of web-based teaching and learning systems
Instructional design for Web-based teaching and learning environments causes problems for two reasons. Firstly, virtual forms of teaching and learning result in little or no direct contact between instructor and learner, making the evaluation of course effectiveness difficult. Secondly, the Web as a relatively new teaching and learning medium still requires more research into learning processes with this technology. We propose data mining – techniques to discover and extract knowledge from a database – as a tool to support the analysis of student learning processes and the evaluation of the effectiveness and usability of
Web-based courses. We present and illustrate different data mining techniques for the evaluation of Web-based teaching and learning systems
Virtual Office Design For The Effectiveness Of Web_based Office Administration Works
Virtual Office is the science of information technology which is a new thing for some people. The word of virtual has a meaning of visible or tangible, it means that in the future an office is intangible because it will be replaced by a system which is specifically designed to replace the role of office by applying web -based computer programming. Nowdays, Offices have been applied are still using a certain place with a wide range of file and requiring a storage cabinet. These issues triggered the researcher tried to design a virtual office with a concept which is able to handle a variety of problems, ranging from archival storage , searching the archives , phone , video conference , sending letters, categorizing archives and saving faculty and staff data. These concepts developed by the researcher offered well organized data that all files or all archives of administrative office tucked neatly away in a database in well organizing so it made easier in searching a spesific archive. The final objective of the research is the improvement of the workers’ performance because it will shorten the time to manage archives or files. Manufacture of incoming mail, outgoing mail, disposition and also numbering letters will be arranged neatly, thus will increase the effectiveness of a worker. (Abstract
Optical Network Virtualisation using Multi-technology Monitoring and SDN-enabled Optical Transceiver
We introduce the real-time multi-technology transport layer monitoring to
facilitate the coordinated virtualisation of optical and Ethernet networks
supported by optical virtualise-able transceivers (V-BVT). A monitoring and
network resource configuration scheme is proposed to include the hardware
monitoring in both Ethernet and Optical layers. The scheme depicts the data and
control interactions among multiple network layers under the software defined
network (SDN) background, as well as the application that analyses the
monitored data obtained from the database. We also present a re-configuration
algorithm to adaptively modify the composition of virtual optical networks
based on two criteria. The proposed monitoring scheme is experimentally
demonstrated with OpenFlow (OF) extensions for a holistic (re-)configuration
across both layers in Ethernet switches and V-BVTs
Technology Contribution to Improve Autistic Children Life Quality
To review published literature on the use of technology and how it has improved autistic children life style. A systematic review of the English literature was performed using the PRISMA guideline. Papers indexed in WOS and Scopus databases were included, adjusted to a timeline between 2016 and 2020 and focused on mobile technology, interventions, improvement of social behavior and communication and autism, aimed to describe the most used mechanism to improve autistic life style. Thirty two (32) papers were included in the review. We obtained 14 papers on the Scopus database and 18 on the WOS database. The majority of studies evidenced the use of virtual reality, mobile devices, video modelling and robots as the most common applications for autism therapies. Technology has caused an improvement in autistic children life quality. The development of mobile applications, virtual reality applications and robots have showed a positive impact reflected in the performance of daily activities and a better understanding of how they feel, how to behave, how to express themselves and interact with others. Technology gives the opportunity to monitor children status; and offers adaptability, safety, and accuracy of the information
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