Grid Resource Information Frameworks
G. Pashov, K. Kaloyanova, K. Boyanov
Abstract
The choice of a suitable information model is a key step to successful deployment and use of the Grid infrastructure. It has to meet strong requirements for scalability, robustness and performance in the heterogeneous and dynamic Grid environment.
In this paper are reviewed the main characteristics of the Grid information models. The basic challenges that have to be taken into account: architecture, data distribution and replication, functionally complete Grid entity sets, etc.
Finally an overview of existing are adressed concepts for information representation in Grid is presented and a comparison of the particular realizations of information services based on LDAP, RDBMS and UDDI is provided.
Efficient Quantum Computing Simulation in GRID Environments
V. Pavlov
Abstract
We describe an implementation of Shor’s quantum algorithm for prime number factorization on a portable universal quantum computing simulator that allows large-scale entirely quantum computation to be carried out in parallel environments. The quantum computing simulator in question is a result of our previous work in which we speculated that its special design will not only allow running efficient simulations of various quantum algorithms for large problem sizes, but will also allow reducing the simulation time further by parallelizing its execution among multiple computing elements. We test these expectations by implementing and running Shor’s algorithm for different problem sizes up to 59 qubits in single - and multi-processing environments, consisting of mainstream computing elements participating in a GRID infrastructure. The results indicate ideal scaling of the simulator as a function of the number of the computing elements involved and thus show that it can be used standalone or in GRID environment as a valuable research tool for performing large scale quantum algorithm simulations.
General Stochastic Modelling for Quantitative Safety Analysis Using Markov Chains and Petri Nets
R. Slovàk, K. Kassev, N. Stoytcheva, E. Ivanov, E. Schnieder
Abstract
An important aspect of safety modeling is the necessity of description of non
deterministic behaviour of the system, which is caused by the stochastic character of the system
environment and system degradation process. In many modeling situations the use of exponential
distribution may be adequate. On the other hand, a reasonable prediction of undesired system
behaviour, can be only obtained by applying more realistic description of stochastic processes. The
high modeling precision determines the system’s dependability, which offers a wide potential for
cost benefit in the system development and operational use. The aim of the article is to present a
practical application of a method for modelling of more general (non-exponential) stochastic
distributions for the purposes of safety analysis of Railway Operation and Control Systems.
Identification, Retrieval and Management of Services in Ambient Networks
N. Kalaydjiev
Abstract
Connecting devices other than workstations to the Internet is becoming commonplace now. Examples are the equipment, traditionally connected to a computer like a printer, a scanner or a disk (file server). In addition, the number of mobile devices like PDA’s and telephones increases rapidly. All these devices are capable of providing services to users. Ambient networks and environments pose unique challenges, different from the challenges in conventional and static networks. Devices that need to join and leave the network dynamically require architectures and protocols aiding at making ease of the interaction between network participants. Service consumers need flexible ways to find the exact service provider they need. Networks like these could have static structure and dynamic content, but also could be spontaneously created (i.e. ad-hoc networks) when devices appear close together. This paper is a survey of protocols and taxonomy of architecture capabilities of existing service discovery technologies.
An Algorithm for Automated Creation of a PC Database Storing Related Text Objects
D. Dimova, K. Onkov
Abstract
An algorithm for automated creation of a relational PC database based on primary text documents is developed. The suggested coding system assigns a natural number to each explicit text object. Two numbers form a pair when the text objects they represent relate to each other. Input data, basic algorithmic operations and general database structure are described. The developed algorithm is applied for creation of the “Phytopharmacy” database that stores and structures the data referring to the cultures, pests and basic groups of pesticides. The presented algorithm and software would be useful appropriate applicable methodology and tool for automated creation of databases storing related text objects.