Addressing performance requirements in the FDT-based design of distributed systems

The development of distributed systems is generally regarded as a complex and costly task, and for this reason formal description techniques such as LOTOS and ESTELLE (both standardized by the ISO) are increasingly used in this process. Our experience is that LOTOS can be exploited at many stages on the design trajectory, from requirements specification to implementation, but that the language elements do not allow direct formalization of performance requirements. To avoid duplication of effort by using two formalisms with distinct approaches, we propose a design method that incorporates performance constraints in an heuristic but effective manner

Fiber Optic Tactical Local Network (FOTLAN)

A 100 Mbit/s FDDI (fiber distributed data interface) network interface unit is described that supports real-time data, voice and video. Its high-speed interrupt-driven hardware architecture efficiently manages stream and packet data transfer to the FDDI network. Other enhancements include modular single-mode laser-diode fiber optic links to maximize node spacing, optic bypass switches for increased fault tolerance, and a hardware performance monitor to gather real-time network diagnostics

Fiber optic voice/data network

An asynchronous, high-speed, fiber optic local area network originally developed for tactical environments with additional benefits for other environments such as spacecraft, and the like. The network supports ordinary data packet traffic simultaneously with synchronous T1 voice traffic over a common token ring channel; however, the techniques and apparatus of this invention can be applied to any deterministic class of packet data networks, including multitier backbones, that must transport stream data (e.g., video, SAR, sensors) as well as data. A voice interface module parses, buffers, and resynchronizes the voice data to the packet network employing elastic buffers on both the sending and receiving ends. Voice call setup and switching functions are performed external to the network with ordinary PABX equipment. Clock information is passed across network boundaries in a token passing ring by preceeding the token with an idle period of non-transmission which allows the token to be used to re-establish a clock synchronized to the data. Provision is made to monitor and compensate the elastic receiving buffers so as to prevent them from overflowing or going empty

Proof of concept of a new Audio Dispatcher

To excel in today’s world, rail controllers need to be able to communicate with numerous personnel across different mobile and fixed networks, in order to make well-informed decisions effortlessly. Audio Dispatcher is a software product that allows the railway control center operators to manage different voice communication systems in an integrated manner, by being able to concentrate them in a single Web graphic interface. It enables operational communication between control centers, train drivers, shunting personnel, maintenance personnel, neighbourhood dispatchers and local train stations. Audio Dispatcher already had two previous versions, however, the second version had some problems and was not according to Thales GTS division latest technological stack. This new version of the Audio Dispatcher is integrated into a multi-platform framework named GDP UI Toolkit whose main advantage is that it facilitates the rapid development of applications based on a predefined toolbox of components and microservices. In the course of this product’s renewal, new functionalities need to be added, such as multimedia file sharing, chat sessions and video calls. This 3rd version also intends to make the product more versatile, easy to set up and configure. The AD product required a new and well-defined interface. This is the main purpose and the problem this dissertation was proposed to solve, in doing so, we developed the HMI for the new Audio Dispatcher system, focusing on two central modules: the Call Manager and the Contact Manager.Para se destacar no mundo de hoje, os controladores ferroviários necessitam de comunicar com várias pessoas em diferentes redes móveis e fixas, para tomar decisões bem informadas sem qualquer esforço. O Audio Dispatcher é um produto de software que permite aos operadores de centros de controlo ferroviário giram numa maneira integrada diferentes sistemas de comunicação de voz, podendo concentrar esses sistemas numa única interface gráfica Web. Este software permite a comunicação operacional entre centros de controlo, maquinistas, pessoal de manutenção e estações de comboio locais. O Audio Dispatcher já tinha duas versões anteriores, porém, a segunda versão apresentava alguns problemas e não estava de acordo com a exigência tecnológica da divisão GTS da Thales. Esta nova versão do Audio Dispatcher está integrada numa framework multiplataforma denominada GDP UI Toolkit, cuja principal vantagem é que facilita o rápido desenvolvimento de aplicações com base numa coleção predefinida de componentes e microsserviços. No decorrer da renovação deste produto, novas funcionalidades serão adicionadas, como a partilha de ficheiros multimédia, chat e vídeo chamadas. Esta 3ª versão pretende também tornar o produto mais versátil, fácil de instalar e configurar. O produto AD precisava de uma nova e bem definida interface. Este é o principal objetivo e o problema que esta dissertação foi proposta a resolver, ao fazê-lo, desenvolvemos a HMI para o novo sistema Audio Dispatcher, com o foco em dois módulos centrais: o Call Manager e o Contact Manager

Literature review of recent, practical - oriented computer networks papers

This thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2009.Cataloged from PDF version of thesis report.Includes bibliographical references (page 61).This thesis will include a literature review of recent practical oriented computer networks papers in premier IEEE conferences. The objective of the thesis is to provide detailed plans for a number of computer network related projects that may be implemented by subsequent BRAC University students. We will do an in-depth study of the selected topics and provide a step by step implementation process.Hasibul IslamHassan SameerIrtiza Ahmad FarooqB. Electrical and Electronic Engineerin

Near-real-time TOMS, telecommunications and meteorological support for the 1987 Airborne Antarctic Ozone Experiment

The goal of the 1987 Airborne Antarctic Ozone Experiment was to improve the understanding of the mechanisms involved in the formation of the Antarctic ozone hole. Total ozone data taken by the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) played a central role in the successful outcome of the experiment. During the experiment, the near-real-time TOMS total ozone observations were supplied within hours of real time to the operations center in Punta Arenas, Chile. The final report summarizes the role which Research and Data Systems (RDS) Corporation played in the support of the experiment. The RDS provided telecommunications to support the science and operations efforts for the Airborne Antarctic Ozone Experiment, and supplied near real-time weather information to ensure flight and crew safety; designed and installed the telecommunications network to link NASA-GSFC, the United Kingdom Meteorological Office (UKMO), Palmer Station, the European Center for Medium-Range Weather Forecasts (ECMWF) to the operation at Punta Arenas; engineered and installed stations and other stand-alone systems to collect data from designated low-orbiting polar satellites and beacons; provided analyses of Nimbus-7 TOMS data and backup data products to Punta Arenas; and provided synoptic meteorological data analysis and reduction

Inter-organisational infrastructures for competitive advantage : strategic alignment in virtual corporations

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