Managing embedded software development in China

Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, February 2004.Includes bibliographical references.As microprocessors have become smaller and cheaper, they are embedded in more and more non-computing products, such as washing machines, elevators, MP3 players and printers. It has been estimated that these products consumed 99% of the worldwide production of microprocessors. I In general, "Embedded system" means a computer system sitting inside a product other than a computer to make the product more flexible and controllable. For example, a modem washing machine has a control software system to execute different "washing programs" for different types of clothes. Embedded systems usually have strict requirements on response time, and the response must be generated within a finite and specified period, though depending on the situation, the time could be within a few milliseconds or a few seconds. Because of the special requirement on response time, embedded systems are sometimes called real-time systems. Embedded systems can be divided into two categories: hard and soft, according to the degree of required "timeliness" 2 . A hard embedded system is stringent on that the response must occur within a specified timeline. Typical examples are flight-control systems and missile control systems. A soft embedded system is less strict: response time is important but the system still can function properly given occasionally missed deadline. Examples are mobile phones, printers, and medical devices. This paper is only concerned with development of the soft-embedded systems, and hence the term "embedded systems" in the paper means "soft embedded systems".by Wei Hu.S.M

Un meta-modèle de composants pour la réalisation d'applications temps-réel flexibles et modulaires

The increase of software complexity along the years has led researchers in the software engineering field to look for approaches for conceiving and designing new systems. For instance, the service-oriented architectures approach is considered nowadays as the most advanced way to develop and integrate fastly modular and flexible applications. One of the software engineering solutions principles is re-usability, and consequently generality, which complicates its appilication in systems where optimizations are often used, like real-time systems. Thus, create real-time systems is expensive, because they must be conceived from scratch. In addition, most real-time systems do not beneficiate of the advantages which comes with software engineering approches, such as modularity and flexibility. This thesis aim to take real time aspects into account on popular and standard SOA solutions, in order to ease the design and development of modular and flexible applications. This will be done by means of a component-based real-time application model, which allows the dynamic reconfiguration of the application architecture. The component model will be an extension to the SCA standard, which integrates quality of service attributs onto the service consumer and provider in order to stablish a real-time specific service level agreement. This model will be executed on the top of a OSGi service platform, the standard de facto for development of modular applications in Java.La croissante complexité du logiciel a mené les chercheurs en génie logiciel à chercher des approcher pour concevoir et projéter des nouveaux systèmes. Par exemple, l'approche des architectures orientées services (SOA) est considérée actuellement comme le moyen le plus avancé pour réaliser et intégrer rapidement des applications modulaires et flexibles. Une des principales préocuppations des solutions en génie logiciel et la réutilisation, et par conséquent, la généralité de la solution, ce qui peut empêcher son application dans des systèmes où des optimisation sont souvent utilisées, tels que les systèmes temps réels. Ainsi, créer un système temps réel est devenu très couteux. De plus, la plupart des systèmes temps réel ne beneficient pas des facilités apportées par le genie logiciel, tels que la modularité et la flexibilité. Le but de cette thèse c'est de prendre en compte ces aspects temps réel dans des solutions populaires et standards SOA pour faciliter la conception et le développement d'applications temps réel flexibles et modulaires. Cela sera fait à l'aide d'un modèle d'applications temps réel orienté composant autorisant des modifications dynamiques dans l'architecture de l'application. Le modèle de composant sera une extension au standard SCA qui intègre des attributs de qualité de service sur le consomateur et le fournisseur de services pour l'établissement d'un accord de niveau de service spécifique au temps réel. Ce modèle sera executé sur une plateforme de services OSGi, le standard de facto pour le developpement d'applications modulaires en Java