Célio Estevan Morón

A visual environment for the development of parallel real-time programs

This work describes a Visual Environment for the Development of Parallel Real-Time programs, a tool whose aim is to facilitate the generation and debugging of source code of applications developed for the Parallel Kernel Virtuoso (Virtuoso is a trademark of Eonic Systems (http://www.eonic.com). When offering support to the kernel, a set of tools is required to help in the development of parallel applications, debugging and analysis of real-time requirements. Within these tools it is worth mentioning: 1- Parallel Programs Generator, 2- Worst Case Execution Time Analyser, 3- Scheduling Analyser, and 4 Parallel Debugger. These four tools are part of the Visual Environment for the Development of Parallel Real-Time Programs, an integrated programming environment for the development of applications executed in a parallel machine. Roughly, this Visual Environment should be able to provide continuity in the development of projects using the most common development methods (traditional or object-oriented), by offering support. during the phases of implementation, debugging and testing. This paper reports on the first two tools and the first one is available for downloading from http://www.dc.ufsear.br/ -tev/tev.html. The second of these tools is already under implementation and the last two tools will be available in a near future.

Phenomenological dynamics of coronal loops using a neural network approach

Abstract The objective of this study is to simulate the X-ray 2D-coronal dynamics using an artificial neural network — multilayer backpropagation algorithm with inputs of Energy Fragmentation Patterns obtained from Yohkoh images in soft and hard X-rays. Details of a single loop structure have been investigated for initial analysis. The images are spatio-temporal series showing the loop-top in Soft X-ray (SXR) and foot points in Hard X-ray (HXR). Using a square electron density gradient model, we have characterized the spatio-temporal loop dynamics concerning its twister-relaxation regime. The performance of this trained network model has been tested with classical image statistics applied to the Yohkoh data. In this paper we show preliminary results indicating that this technique can be useful for coronal dynamics analysis.

QoS Proxy Architecture for Real Time RPC with Traffic Prediction

Currently, there are many research works focused at the creation of architectures that support QoS for real time multimedia applications guarantees. However, those architectures do not support the traffic of RT-RPCs whose requirements (i.e. priority and deadline) are harder than those of multimedia applications. The aim of this work is to propose an architecture of QoS proxy for RT-RPCs that uses Box-Jenkins time series models in order to predict future traffic characteristics of RT-RPCs that pass through the proxy, allowing the anticipated allocation of the necessary resources to attend the predicted demand and the choice of policies aimed at the adaptation of the proxy to the states of its network environment.

A LOW COST STEERABLE RADIO-TELESCOPE

We present the technical characteristics of a low-cost radio telescope for solar/non solar observations at decimetric (1200–1700 MHz) and centimetric (2700 and 5000 MHz) wavelengths known as Brazilian Decimetric Array (BDA). The technical specifications of the antenna, tracking system, log-periodic feed, preamplifier and the frequency-synthesised receiver with a Single Side Band (SSB) video output of 2.5 MHz are given.

From design to implementation using the Parallel Program Generator

The development of parallel applications usually require the use of different techniques for each of the phases of development. The paper reports on the process of moving from the design of a parallel real time application into its implementation using the Parallel Program Generator. This tool is part of a visual environment for the development of parallel real time programs, an integrated environment for the development of applications executed in a parallel machine. The aim of the tool being described here is to facilitate the generation and debugging of source code of parallel real time applications. As the aim of the environment is to provide continuity in the development of projects using the most common development methods (traditional or object oriented), an example is provided in order to show the potential of the tool, whose first version is available for downloading at http://www.dc.ufscar.br//spl sim/tev/tev.html.

A gateway architecture for QoS management considering time constraint application

Time constraint applications that use the Internet/Intranet (e.g. audio and video streaming, VoIP and RT-RPC messages), require some QoS mechanisms in order to deliver the package before the end of its deadline. Prioritizing the traffic of the packages generated by these applications in relation to other packages is one way of trying to minimize the loss of deadlines. This paper presents an architecture of gateway with QoS and traffic forecast aiming to favour applications requests with time constraints. The Gateway classifies traffic, based on IEEE 802.1q standard, on six classes with different priorities. It also uses the mathematical model Box-Jenkins to forecast the volume of traffic for each class of service and to allocate resources to meet them according to their priority. The results of the simulations show a significant gain with the proposed use of the gateway.

A parallel application for 3D reconstruction of coronal loops using image morphing

Abstract This paper presents an approach for 3D reconstruction of X-ray tomographic images of coronal loops, observed on the solar atmosphere by the Japanese satellite Yohkoh. In this approach, the intermediate cross-sections images of the magnetic loop are generated with image morphing controlled by a Bezier curve in arc shape. Due to the high computational costs involved in the processing and visualization of solar images, a parallel application for 3D reconstruction of a coronal loop was implemented to execute in the Atlas parallel system.

From MultiTask to MultiCore: Design and Implementation Using an RTOS

Practice has shown that programming a new multicore system is a greater challenge than previously thought. The challenge is to produce the resulting system in a way, which is as easy as sequential programming. This new trend has changed the way we think about the whole development process. The aim of this work is to show that it is possible to develop a multicore embedded system application using existing tools, while at the same time, obtaining reuse. This process is carried out in a cyclic and increasing manner, generating a more refined version of the application at each iteration. The development process consists of five phases: Multitask Modelling, Code Generation, Test/Debugging, Mapping Tasks to Cores and Tuning the Application. The three initial ones are carried out using the Visual RTXC tool, whereas the last two use the performance tool TAU. Using a small application, a Case Study shows how the proposed development process works and the steps involved in the implementation of an embedded system.

Image morphing applied to 3D reconstruction of coronal loops

We present a new approach for 3D reconstruction of X-ray tomographic images of a magnetic structure, called coronal loop, observed on the solar atmosphere by the Japanese satellite Yohkoh. In this approach, the intermediate cross sections images of the magnetic loop are generated with image morphing controlled by a Bezier curve in arc shape. In space science, this approach has an important application to obtain information about the solar explosions that may cause serious perturbations in terrestrial communication systems.

A program generator for real-time remote procedure call communication

The Visual Environment for the Development of Parallel Real-Time Programs (http://www.dc.ufscar.br/~tev) has been designed to facilitate the change from the sequential to the parallel paradigm. This graphic environment enables the fast prototyping of parallel applications executed in the realtime operating system Virtuoso from Eonic Systems (http://www.eonic.com). Such parallel applications run on a parallel machine making intensive calculations which have little or no interaction with the outside world. However, with the advance in the Internet it has been possible to develop programs capable of remotely executing, manipulating and monitoring such applications. This article focuses on the Real-Time Remote Procedure Call Generator which is aimed at managing the development of Java applications able to interact with parallel real-time programs through remote procedure calls that consider time requirements and guarantee the atomicity of the remote execution.