Search results for " computing"

Use of Supercomputing towards the Generation of a Process Execution Plan in Distributed Real-Time Systems

2010

This work consider the scheduling of periodic tasks or processes with real-time constraints in a distributed environment. Each task must be executed meeting deadlines, precedence relationships and resources constraints. The problem of scheduling tasks on a distributed environment can be viewed as a problem of assigning processes to the processors but keeping the schedulability in local environments. Thus, the problem can be divided in two phases: the first phase is assigning processes to processors and the second is to schedule assigned processes in each processor in the distributed environment. This paper focuses in the first phase. It introduces a heuristic mechanism for assigning process…

Potential implementation of reservoir computing models based on magnetic skyrmions

2018

Reservoir Computing is a type of recursive neural network commonly used for recognizing and predicting spatio-temporal events relying on a complex hierarchy of nested feedback loops to generate a memory functionality. The Reservoir Computing paradigm does not require any knowledge of the reservoir topology or node weights for training purposes and can therefore utilize naturally existing networks formed by a wide variety of physical processes. Most efforts prior to this have focused on utilizing memristor techniques to implement recursive neural networks. This paper examines the potential of skyrmion fabrics formed in magnets with broken inversion symmetry that may provide an attractive phy…

Object Clustering Methods and a Query Decomposition Strategy for Distributed Object-Based Information Systems

1999

Emerging developments and advances in distributed processing have created a need for tools and methods to partition and distribute information systems across interconnected processors. In particular, distribution approaches which take into account the key characteristics of OO concepts are required to extend traditional fragmentation results to object oriented database systems. To fulfill the above requirements, we propose a methodology for the distribution design of object-based information systems. The underlying approach consists of techniques and heuristics that can be used to create clusters of inter-related object classes that can be fragmented interdependently, producing distribution…

HybridS: A Scheme for Secure Distributed Data Storage in WSNs

2008

In unattended wireless sensor networks (WSNs), data is stored locally or at designated nodes upon sensing, and users can access it on demand. This paradigm can improve energy efficiency by making use of the upcoming cheap and large flash memory, as well as system robustness. Nevertheless, the security and dependability of distributed storage are critical for the applicability of such WSNs. In this paper, we propose a secure and dependable data storage scheme by taking advantages of secret sharing and Reed-Solomon code, which has computational security and yet maintains optimal data size. The extensive analysis verifies our scheme can provide secure and dependable data storage in WSNs in the…

A recognize-and-accuse policy to speed up distributed processes

1994

A resilient distributed measurement system for smart grid application

2020

Since the production of energy from renewable energy sources is strongly increasing, the migration from the classical electric grid toward the smart grid is becoming a reality. Distribution System Operators, along with the control of the entire network and its stability, need to address the security and the reliability of the communication channels and the data itself. In this paper a solution is proposed to address these issues. It is based on a distributed measurement system that relies on a wireless network as well as a redundant Power Line communication system in order to transfer the electrical measures to a centralized SCADA server. The collected data are used to run a power flow algo…

Memory Resource Management for Real-Time Systems

2007

Dynamic memory storage has been widely used for years in computer science. However, its use in real-time systems has not been considered as an important issue, and memory management has not receive much consideration, whereas today's real-time applications are often characterized by highly fluctuating memory requirements. In this paper we present an approach to dynamic memory management for real-time systems. In response to application behavior and requests, the underlying memory management system adjusts resources to meet changing demands and user needs. The architectural framework that realizes this approach allows adaptive allocation of memory resources to applications involving both per…

The differences between distributed shared memory caching and proxy caching

2000

The authors discuss the similarities in caching between the extensively studied distributed shared memory systems and the emerging proxy systems. They believe that several of the techniques used in distributed shared memory systems can be adapted and applied to proxy systems.

An empirically grounded agent based model for modeling directs, conflict detection and resolution operations in air traffic management

2017

We present an agent based model of the Air Traffic Management socio-technical complex system that aims at modeling the interactions between aircrafts and air traffic controllers at a tactical level. The core of the model is given by the conflict detection and resolution module and by the directs module. Directs are flight shortcuts that are given by air controllers to speed up the passage of an aircraft within a certain airspace and therefore to facilitate airline operations. Conflicts resolution between flight trajectories can arise during the en-route phase of each flight due to both not detailed flight trajectory planning or unforeseen events that perturb the planned flight plan. Our mod…

Programming languages for data-Intensive HPC applications: A systematic mapping study

2020

This work is a result of activities from COST Action 10406 High -Performance Modelling and Simulation for Big Data Applications (cHiPSet), funded by the European Cooperation in Science and Technology. FCT, Portugal for grants: NOVA LINCS Research Laboratory Ref. UID/ CEC/ 04516/ 2019); INESC-ID Ref. UID/CEC/50021/2019; BioISI Ref. UID/MULTI/04046/2103; LASIGE Research Unit Ref. UID/CEC/00408/ 2019. A major challenge in modelling and simulation is the need to combine expertise in both software technologies and a given scientific domain. When High-Performance Computing (HPC) is required to solve a scientific problem, software development becomes a problematic issue. Considering the complexity…