From RF-Microsystem Technology to RF-Nanotechnology

The RF microsystem technology is believed to introduce a paradigm switch in the wireless revolution. Although only few companies are to date doing successful business with RF-MEMS, and on a case-by-case basis, important issues need yet to be addressed in order to maximize yield and performance stability and hence, outperform alternative competitive technologies (e.g. ferroelectric, SoS, SOI,…). Namely the behavior instability associated to: 1) internal stresses of the free standing thin layers (metal and/or dielectric) and 2) the mechanical contact degradation, be it ohmic or capacitive, which may occur due to low forces, on small areas, and while handling severe current densities.The investigation and understanding of these complex scenario, has been the core of theoretical and experimental investigations carried out in the framework of the research activity that will be presented here. The reported results encompass activities which go from coupled physics (multiphysics) modeling, to the development of experimental platforms intended to tackles the underlying physics of failure. Several original findings on RF-MEMS reliability in particular with respect to the major failure mechanisms such as dielectric charging, metal contact degradation and thermal induced phenomena have been obtained. The original use of advanced experimental setup (surface scanning microscopy, light interferometer profilometry) has allowed the definition of innovative methodology capable to isolate and separately tackle the different degradation phenomena under arbitrary working conditions. This has finally permitted on the one hand to shed some light on possible optimization (e.g. packaging) conditions, and on the other to explore the limits of microsystem technology down to the nanoscale. At nanoscale indeed many phenomena take place and can be exploited to either enhance conventional functionalities and performances (e.g. miniaturization, speed or frequency) or introduce new ones (e.g. ballistic transport). At nanoscale, moreover, many phenomena exhibit their most interesting properties in the RF spectrum (e.g. micromechanical resonances). Owing to the fact that today’s minimum manufacturable features have sizes comparable with the fundamental technological limits (e.g. surface roughness, metal grain size, …), the next generation of smart systems requires a switching paradigm on how new miniaturized components are conceived and fabricated. In fact endowed by superior electrical and mechanical performances, novel nanostructured materials (e.g. carbon based, as carbon nanotube (CNT) and graphene) may provide an answer to this endeavor. Extensively studied in the DC and in the optical range, the studies engaged in LAAS have been among the first to target microwave and millimiterwave transport properties in carbon-based material paving the way toward RF nanodevices. Preliminary modeling study performed on original test structures have highlighted the possibility to implement novel functionalities such as the coupling between the electromagnetic (RF) and microelectromechanical energy in vibrating CNT (toward the nanoradio) or the high speed detection based on ballistic transport in graphene three-terminal junction (TTJ). At the same time these study have contributed to identify the several challenges still laying ahead such as the development of adequate design and modeling tools (ballistic/diffusive, multiphysics and large scale factor) and practical implementation issues such as the effects of material quality and graphene-metal contact on the electrical transport. These subjects are the focus of presently on-going and future research activities and may represent a cornerstone of future wireless applications from microwave up to the THz range

Management: A bibliography for NASA managers

This bibliography lists 630 reports, articles and other documents introduced into the NASA Scientific and Technical Information System in 1991. Items are selected and grouped according to their usefulness to the manager as manager. Citations are grouped into ten subject categories: human factors and personnel issues; management theory and techniques; industrial management and manufacturing; robotics and expert systems; computers and information management; research and development; economics, costs and markets; logistics and operations management; reliability and quality control; and legality, legislation, and policy

Techniques d'interaction multimodales pour l'accès aux mathématiques par des personnes non-voyantes

Cette thèse s‟inscrit dans le domaine de l‟interaction Homme-Machine et plus précisément dans celui des interfaces multimodales destinées aux non-voyants. Elle a pour thème principal la présentation des expressions mathématiques aux non-voyants. Pour les étudiants non-voyants, apprendre les mathématiques est une tâche ardue et peut constituer une barrière, les séparant des disciplines techniques. Les travaux de recherche présentés ici décrivent les problèmes rencontrés dans la conception d‟un système permettant l‟accès aux mathématiques pour les utilisateurs déficients visuels. En effet, nous présentons une analyse des outils existants puis nous proposons des solutions pour combler leurs insuffisances. Nous exposons les techniques utilisées au sein de notre système pour répondre aux problèmes de la présentation des expressions mathématiques aux non-voyants. Nous exploitons la multimodalité comme technique d‟interaction pour développer des applications destinées à ce type d‟utilisateurs parce qu‟elle offre plusieurs opportunités grâce à sa richesse des interactions. Nous dotons également notre système d‟un comportement intelligent pour assurer une certaine autonomie à l‟utilisateur. En effet, le système est capable de présenter l‟information en fonction du contexte de l‟interaction (c-à-d. l‟utilisateur, son environnement et sa machine) et de la nature de l‟information. Le système est « pervasif » et adaptatif. L‟accès à l‟information est assuré n‟importe où n‟importe quand et il s‟adapte dynamiquement aux changements du contexte tout en fournissant continuellement des services à l‟utilisateur non-voyant, sans intervention humaine. Pour rendre le système adaptatif, nous avons élaboré un modèle qui détermine la complexité de l‟expression mathématique et nous avons intégré une technique d‟apprentissage automatique pour implémenter les mécanismes de décisions. Enfin, l‟architecture proposée est du type multi-agent. Ces techniques ont été validées par des études de cas et en utilisant les réseaux de Pétri et l‟outil de simulations JADE

Technological roadmap on AI planning and scheduling

At the beginning of the new century, Information Technologies had become basic and indispensable constituents of the production and preparation processes for all kinds of goods and services and with that are largely influencing both the working and private life of nearly every citizen. This development will continue and even further grow with the continually increasing use of the Internet in production, business, science, education, and everyday societal and private undertaking. Recent years have shown, however, that a dramatic enhancement of software capabilities is required, when aiming to continuously provide advanced and competitive products and services in all these fast developing sectors. It includes the development of intelligent systems – systems that are more autonomous, flexible, and robust than today’s conventional software. Intelligent Planning and Scheduling is a key enabling technology for intelligent systems. It has been developed and matured over the last three decades and has successfully been employed for a variety of applications in commerce, industry, education, medicine, public transport, defense, and government. This document reviews the state-of-the-art in key application and technical areas of Intelligent Planning and Scheduling. It identifies the most important research, development, and technology transfer efforts required in the coming 3 to 10 years and shows the way forward to meet these challenges in the short-, medium- and longer-term future. The roadmap has been developed under the regime of PLANET – the European Network of Excellence in AI Planning. This network, established by the European Commission in 1998, is the co-ordinating framework for research, development, and technology transfer in the field of Intelligent Planning and Scheduling in Europe. A large number of people have contributed to this document including the members of PLANET non- European international experts, and a number of independent expert peer reviewers. All of them are acknowledged in a separate section of this document. Intelligent Planning and Scheduling is a far-reaching technology. Accepting the challenges and progressing along the directions pointed out in this roadmap will enable a new generation of intelligent application systems in a wide variety of industrial, commercial, public, and private sectors

RFID Technology in Intelligent Tracking Systems in Construction Waste Logistics Using Optimisation Techniques

Construction waste disposal is an urgent issue for protecting our environment. This paper proposes a waste management system and illustrates the work process using plasterboard waste as an example, which creates a hazardous gas when land filled with household waste, and for which the recycling rate is less than 10% in the UK. The proposed system integrates RFID technology, Rule-Based Reasoning, Ant Colony optimization and knowledge technology for auditing and tracking plasterboard waste, guiding the operation staff, arranging vehicles, schedule planning, and also provides evidence to verify its disposal. It h relies on RFID equipment for collecting logistical data and uses digital imaging equipment to give further evidence; the reasoning core in the third layer is responsible for generating schedules and route plans and guidance, and the last layer delivers the result to inform users. The paper firstly introduces the current plasterboard disposal situation and addresses the logistical problem that is now the main barrier to a higher recycling rate, followed by discussion of the proposed system in terms of both system level structure and process structure. And finally, an example scenario will be given to illustrate the system’s utilization

Propagation channel measurement system development and channel characterization at 5.3 GHz

The wireless access has proven its usability for reliable communication and data conveying link for a long time. The ever growing usage of wireless communications systems has been driving the research to study even faster and more interference tolerant wireless solutions. A key concept towards achieving these goals are the detailed analysis and modeling of the propagation channel. In both of these aspects the availability of reliable measurement data is a prerequisite. This thesis concentrates on contributing to the measurement system development in single- and dual-link cases as well as measurement data analysis for specific wireless systems. In the first part of the thesis the physical radiowave propagation phenomena are briefly related to the challenges of the modern wireless communication systems. Through the analysis of the propagation channel conducted earlier in the literature, the main phenomena for modeling the propagation channel are illustrated, and the current modeling approaches are described. The hardware related design challenges are described along with the recent achievements in the measurement system development. Specifically, the design of antenna arrays for estimation of the parameters of the double directional channel model is illustrated. A measurement system developed for characterizing the double directional channel in the 5.3 GHz frequency range is presented along with the evaluation of the accuracy of the measurment system for the spatial characterization. The developed measurement system is further extended to enable simultaneous, double directional dual-link propagation channel measurements, and the first directional results from a measurement campaign are presented. In the second part, the important feature of the spatial dimensionality of the propagation channel is considered through measurement data acquired using the developed measurement system. The basics of the single- and dual-link MIMO communications systems and cooperative communications are presented. The analysis of the spatial domain used in MIMO communications systems is extended to multiuser scenario. Furthermore, cooperative communications system is analyzed