Matra

About: Matra is a based out in . It is known for research contribution in the topics: Signal & Detector. The organization has 1330 authors who have published 1216 publications receiving 17967 citations.

Software maintenance: an analysis of industrial needs and constraints

Abstract: The results are given of a series of case studies conducted at different industrial sites in the framework of the ESF/EPSOM (Eureka Software Factory/European Platform for Software Maintenance) project. The approach taken in the case studies was to directly contact software maintainers and obtain their own view of their activity, mainly through the use of interactive methods based on group work. This approach is intended to complement statistical studies which can be found in the literature, by presenting the perspective of the maintainers based on their experience. The aim of these studies has been to gain a better understanding of maintenance needs and constraints, and to highlight directions which could lead to improvements in the quality and efficiency of maintenance activities. The results obtained tend to conform the main preoccupations of the maintenance community, with an emphasis on two types of needs which appear crucial in the domains of activity of the partners, namely: the transfer, preservation and maintenance of knowledge; and the mastering of the maintenance process. >

Autonomous star identification

Abstract: A method and apparatus compare a star to be identified within an image with data in a database generated from known star data. According to a first aspect of the invention, a target star to be identified within an image is selected, and a number of adjacent stars, normally two, are also selected. The separation values between the stars and a geometric identity for each separation value are determined. This data is compared with corresponding data stored in a database for known stars, where the data in the database is generated using the same technique. According to a second aspect of the invention, a target star is selected, and adjacent stars are selected from an annulus centered on the target star. The separation values for the stars are determined and compared with known separation values stored in a database, where the data in the database is generated using the same annulus centered on each known target star.

Rotary electric motor having controller and power supply integrated therein

Abstract: A rotary electric motor is formed within a cylindrical rotor housing structure that surrounds an annular stator ring. The permanent magnet rotor is configured in an annular ring coaxial with, and outside of, the stator. The stator ring contains a plurality of wound core segments that are ferromagnetically isolated from each other. The core segments are secured to a rigid skeletal structure that is centrally fixed to a stationary shaft. The stator support structure is formed of spine members that extend radially away from the center. U-shaped plates at the outer ends of the spine members engage adjacent pair of stator segments. Within the inner periphery of the stator ring, space is provided within which motor control circuitry and battery power supply may be incorporated.

A process model for the maintenance of large space systems software

Abstract: The results are given of a study carried out in the framework of the ESF/EPSOM (Eureka Software Factory/European Platform for Software Maintenance) project to analyze the processes of software maintenance followed in the European space industry. First, the authors present a generic process, from which models for usual operational processes can be easily derived. Then, they show how this generic process is to be instantiated, taking as an example a reference organization defined by the European Space Agency. Finally, two variants of this instantiated process are briefly presented, in order to consider emergency and routine situations. >

Performance evaluation of the R-BTMA protocol in a distributed mobile radio network context

Abstract: A reservation multiple-access protocol for mobile communication in a decentralized environment is proposed and investigated both analytically and by simulation. The reservation-busy-tone multiple access (R-BTMA) is a fully distributed and reservation-based protocol. It is a medium access control (MAC) protocol designed for short-range communications between vehicles in a decentralized context (i.e., without a base station). The specificity of this protocol relies on the utilization of two different characteristic channels. Information is transmitted on the data channel (DC), whereas the busy-tone channel (BTC) is used for signalling traffic. The range of the BTC is typically longer than the DC one. The throughput and access delay performance are studied in the particular context of two cells sharing a common BTC. The traffic between the vehicles is supposed to be regular and is parameter sharing. The comparison of the model analysis results to those obtained by the simulative approach shows a satisfactory matching. >