Civil aircraft advanced avionics architectures - an insight into saras avionics, present and future perspective

Traditionally, the avionics architectures being implemented are of federated nature, which means that each avionics function has its own independent, dedicated fault-tolerant computing resources. Federated architecture has great advantage of inherent fault containment and at the same time envelops a potential risk of massive use of resources resulting in increase in weight, looming, cost and maintenance as well. With the drastic advancement in the computer and software technologies, the aviation industry is gradually moving towards the use of Integrated Modular Avionics (IMA) for civil transport aircraft, potentially leading to multiple avionics functions housed in each hardware platform. Integrated Modular Avionics is the most important concept of avionics architecture for next generation aircrafts. SARAS avionics suite is purely federated with almost glass cockpit architecture complying to FAR25. The Avionics activities from the inception to execution are governed by the regulations and procedures under the review of Directorate General of Civil Aviation (DGCA). Every phase of avionics activity has got its own technically involvement to make the system perfect. In addition the flight data handling, monitoring and analysis is again a thrust area in the civil aviation industry leading to safety and reliability of the machine and the personnel involved. NAL has been in this area for more than two decades and continues to excel in these technologies

Process Support for Cooperative Work on the World Wide Web

The World Wide Web is becoming a dominating factor in information technology. Consequently, computer supported cooperative work on the Web has recently drawn a lot of attention. “Process Support for Cooperative Work” (PSCW) is a Web based system supporting both structured and unstructured forms of cooperation. It is a combination of the “Basic Support for Cooperative Work” (BSCW) shared workspace system and the Merlin Process Support Environment. The current PSCW prototype offers a loose connection, in effect extending BSCW with a gateway to Merlin. With this prototype we have successfully addressed the technical issues involved; further integration of functionality should not pose any real problems. We focus on the technical side of the PSCW system, which gives a good insight into the issues that have to be addressed generally in the construction of Web based groupware

A State-of-the-art Integrated Transportation Simulation Platform

Nowadays, universities and companies have a huge need for simulation and modelling methodologies. In the particular case of traffic and transportation, making physical modifications to the real traffic networks could be highly expensive, dependent on political decisions and could be highly disruptive to the environment. However, while studying a specific domain or problem, analysing a problem through simulation may not be trivial and may need several simulation tools, hence raising interoperability issues. To overcome these problems, we propose an agent-directed transportation simulation platform, through the cloud, by means of services. We intend to use the IEEE standard HLA (High Level Architecture) for simulators interoperability and agents for controlling and coordination. Our motivations are to allow multiresolution analysis of complex domains, to allow experts to collaborate on the analysis of a common problem and to allow co-simulation and synergy of different application domains. This paper will start by presenting some preliminary background concepts to help better understand the scope of this work. After that, the results of a literature review is shown. Finally, the general architecture of a transportation simulation platform is proposed

A system design for human factors studies of speech-enabled Web browsing

This paper describes the design of a system which will subsequently be used as the basis of a range of empirical studies aimed at discovering how best to harness speech recognition capabilities in multimodal multimedia computing. Initial work focuses on speech-enabled browsing of the World Wide Web, which was never designed for such use. System design is complete, and is being evaluated via usability testing

Study on thermal model for calculating transformer hot Spot temperature

A power transformer is a static piece of apparatus with two or more windings which, by electromagnetic induction, transforms a system of alternating voltage and current into another system of voltage and current usually of different values and at same frequency for the purpose of transmitting electrical power. The hot spot temperature depends on instantaneous load and ambient temperature, winding design and also cooling model. There are two possible methods for hotspot temperature determination. The first method is to measure the hot spot temperature using a fiber optic, and other is to calculation the hotspot temperature using transformer thermal models. It was noticed that the hot spot temperature rise over top oil temperature due to load changes is a function depending on time as well as the transformer loading (overshoot time dependent function). It has also been noticed that the top oil temperature time constant is shorter than the time constant suggested by the present IEC loading guide, especially in cases where the oil is guided through the windings in a zigzag pattern for the ONAN and ONAF cooling modes. This results in winding hottest spot temperatures higher than those predicted by the loading guides during transient states after the load current increases, before the corresponding steady states have been reached. This thesis presents more accurate temperature calculation methods taking into account the findings mentioned above. The models are based on heat transfer theory, application of the lumped capacitance method, the thermal-electrical analogy and definition of nonlinear thermal resistances at different locations within a power transformer. The methods presented in this thesis take into account all oil physical parameters change and loss variation with temperature. In addition, the proposed equations are used to estimate the equivalent thermal capacitances of the transformer oil for different transformer designs and winding-oil circulations. The models are validated using experimental results, which have been obtained from the normal heat run test performed by the transformer manufacturer at varying load current on a 250-MVA-ONAFcooled unit, a 400-MVA-ONAF-cooled unit and a 2500-KVA-ONAN-cooled unit. The results are also compared with the IEC 60076-7:2005 loading guide method. Keywords: power transformers, hot spot temperature, top oil temperature, non-linear therma

A NPC Behaviour Definition System for Use by Programmers and Designers

In this paper we describe ZBL/0, a scripting system for defining NPC (Non Player Character) behaviour in FPS (First Person Shooter) games. ZBL/0 has been used to illustrate the use of scripting systems in computer games in general and the scripting of NPC behaviour in particular in the context of a book on game development. Many novice game designers have clear ideas about how the computer game they imagine should work but have little knowledge – if any – about how their ideas can be implemented. This is why books on game creation (design, programming etc.), as well as all-in-one game creation systems – especially designed for ease of use and intended for an amateur audience – enjoy great popularity. A large proportion of these books however merely present solutions in the form of descriptions and explanations of specific implementations with inadequate explanations of principles. While this may benefit rapid application development it often does not lead to a deeper understanding of the underlying concepts. The understanding of rule-based behaviour definition through simple scripting in computer games and the development of such scripts by programmers and designers is what we aim to address with the ZBL/0 system