Vatten är en nödvändig resurs för allt liv på jorden. Med en ökande befolkningsmängd förväntas även sötvattenanvändningen att öka, vilket ställer krav på att hanteringen av de vattenresurser som finns sker på ett hållbart sätt. Jordbrukssektorn är i dagsläget den största konsumenten av vatten, varpå det är viktigt att uppmärksamma konsumenter om vattenanvändning vid produktion av livsmedel så att kunskapen ökar kring hur vatten används idag. Ett verktyg för att bedöma miljöpåverkan från vattenanvändning är det så kallade vattenfotavtrycket. De senaste åren har flera beräkningsmetoder tillkommit för att beräkna vattenfotavtryck, och dessa tar hänsyn till olika aspekter. Syftet med denna studie var att utvärdera tre sådana metoder och använda dem för att beräkna vattenfotavtrycket för ett antal livsmedel, jämföra resultatet och slutligen ta fram en rekommendation kring vilken eller vilka metoder som lämpar sig för konsumentvägledning. De metoder som undersöktes var TOTAL som är en metod av Water Footprint Network (WFN), metoden WSI och metoden AWARE. Resultatet visade att vissa nötter fick särskilt högt vattenfotavtryck oavsett vilken metod som användes, för exempelvis mandlar erhölls med respektive metod ett vattenfotavtryck motsvarande 15 m3 vatten/kg, 3,3 m3 WSI-H2O-ekvivalenter/kg samt 165 m3 AWARE-H2O-ekvivalenter/kg. Att resultaten har olika enheter samt storleksordningar beror på att metoderna är olika uppbyggda. Generellt fick baljväxter, spannmål samt frukt och grönt låga resultat, dock varierade resultaten något beroende på vilken metod som användes. Detta beror bland annat på att endast WSI och AWARE tar hänsyn till hur den lokala vattensituationen ser ut där vattnet används. Vid jämförelse av metoderna ansågs både metoden TOTAL samt AWARE vara lämpliga att använda för konsumentvägledning då den förstnämnda är väl beprövad samt lättförstådd medan den sistnämnda är en uppdaterad indikator som tar hänsyn till lokal vattenbrist. / Water is a vital resource for all life on earth. With an increasing population, the use of freshwater is also expected to increase, which requires a sustainable management of existing water resources. The agricultural sector is currently the largest consumer of water, and it is important to pay attention to consumers about water use in food production so that knowledge is increasing about how water is used today. The so-called water footprint is a tool for assessing the amount of water used to produce a good or a service. In recent years, several calculation methods have been added to calculate water footprints, and these take into account various aspects. The purpose of this study was to evaluate three such methods and use them to calculate the water footprint for a number of foods, compare the results and finally give a recommendation on which method or methods that are best suited for consumer guidance. The assessed methods were TOTAL by Water Footprint Network (WFN), the WSI method and the AWARE method. The results showed that some nuts had a particularly high water footprint regardless of the method used. Almonds, for example, obtained with each method a water footprint corresponding to 15 m3 water/kg, 3.3 m3 WSI-H2O-equivalents/kg and 165 m3 AWARE-H2O-equivalents/kg. The fact that the results have different units and orders of magnitude is because the different structure of the methods. Generally, legumes, cereals and fruits and vegetables had low water footprints, but the results varied somewhat depending on the method used. This is partly due to the fact that only WSI and AWARE take into account how the water situations looks where the water is used. When comparing the methods, both TOTAL and AWARE were considered suitable for use for consumer guidance, since the former is well-proven and easily understood while the latter is an updated indicator that takes local water shortage into account.

Cette thèse présente des méthodes et outils de conception de systèmes integres sur tranche entière (wafer scale intégration). L'application traitée (dans le cadre d'un projet européen esprit) est une architecture constituée d'un réseau 2d de 6720 processeurs (pe) monobits, destinée au traitement d'image de bas niveau. Pour tolérer les défauts de fin fabrication, une approche hiérarchisée a été implantée. Au niveau sous-système, une technique de redondance figee a consiste a implanter une colonne de pes de réserve, destines a remplacer les pes défaillants. Au niveau tranche entière, une technique de construction d'une cible maximale n'utilisant que des sous-systèmes s'appuient sur l'implantation d'un réseau de commutateurs permettant d'éviter les sous-systèmes défaillants. Une architecture originale des réseaux de commutateurs contrôle a partir des plots externes et des algorithmes efficaces de définition et construction du réseau opérationnel constituent les points forts de cette thèse

Un algorithme récurrent de la phase de reconnaissance d'un réseau mono couches de Hopfield a été implante. Le problème lie à l'interconnexion complète des neurones a été implantée sur une architecture systolique 2d ou chaque processeur représente une interaction neurone/neurone. Un circuit intégré de 16 neurones, soit 256 synapses, a été réalisé en technologie CMOS. Un tel circuit permet d'effectuer plus d'un demi milliard d'opérations synaptiques par seconde

In recent years, the conventional Flash memory with floating structure is expected to reach physical limits as devices scaling down in near future. In order to overcome this problem, alternative memory technologies have been widely investigated. And the resistance random access memory (RRAM) has attracted extensive attention for the application in next generation nonvolatile memory, due to the excellent memory property including lower consumption of energy, lower operating voltage, higher density, fast operating speed, simple structure, higher endurance, retention and process compatibility with CMOS. In this study, the tungsten-based oxide is chosen as RRAM switching layer because the tungsten is compatible with the present complementary metal oxide semiconductor (CMOS) process. The Pt/WOX/TiN structure device cells had the resistance switching property successfully. However, the experiment result revealed the inferior resistance switching property. The resistance switching characteristic of the WOX thin film is extremely unstable, it is impossible to become the products. Compared with WOX, the resistance switching property of WSiOX RRAM device is improved substantially such as stability of resistance states and reliability of device. In second parts, we purposed two methods to enhance the device switching characteristic, including controlling the filament formation/ interruption in the W doped SiOX layer and restricting oxygen movement in the WSiON layer. Finally, the transport mechanisms of carrier is analyzed and researched from the current-voltage (I-V) switching characteristic of the device. A designed circuit was used in this study to accurately observe the resistance switching process with a pulse generator and oscilloscope, which reveals that the switching process is related to both time and voltage. The oxygen movement will drift in the low temperature due to the electrical field and restricted the crystal lattice vibration. But, it will diffuse through thermal dynamics in the high temperature.

L'objet de cette étude est la conception d'une mémoire statique intégrée sur tranche (4.5 mbits). Cette mémoire réalisée à partir de cellules de 64kbits est tolérante aux défauts de fin de fabrication. Des éléments en réserve remplacent les éléments défectueux à l'aide des connexions du type grille flottante fets ou fusible et antifusible. Le travail de recherche a consisté:<br />-à étudier la faisabilité de cette mémoire<br />-à définir l'architecture d'une telle mémoire en tenant compte du rendement<br />-à définir une stratégie de test pour l'ensemble du circuit<br />-à étudier les dispositifs de connexion/déconnexion qui permettront de réaliser physiquement la mémoire finale -à développer des algorithmes de configuration qui détermineront les groupes de cellules en paquets de 256kbits. <br />Ce travail a été réalisé dans le cadre du projet Esprit-824. Un premier essai de fabrication a permis de caractériser les dispositifs de connexion. La mémoire de 4.5 mbits a été envoyée en fabrication fin 1987

This master thesis emphasizes the importance of aviation meteorological data for flight planning and for making inflight strategic decisions. It describes conventional ways of obtaining meteorological data before and during the flight. It provides the overview of alternative ways of acquiring weather related information. The master thesis compares how hazardous meteorological phenomena - thunderstorms, turbulence and icing - are displayed within the described commercial products.

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This thesis investigates the potential of wafer-scale integration (WSI) for the implementation of low-cost fine-grain parallel processing computer systems. As WSI is a relatively new subject, there was little work on which to base investigations. Indeed, most WSI architectures existed only as untried and sometimes vague proposals. Accordingly, the research strategy approached this problem by identifying a representative WSI structure and architecture on which to base investigations. An analysis of architectural proposals identified associative memory to be general purpose parallel processing component used in a wide range of WSI architectures. Furthermore, this analysis provided a set of WSI-level design requirements to evaluate the sustainability of different architectures as research vehicles. The WSI-ASP (WASP) device, which has a large associative memory as its main component is shown to meet these requirements and hence was chosen as the research vehicle. Consequently, this thesis addresses WSI potential through an in-depth investigation into the feasibility of implementing a large associative memory for the WASP device that meets the demanding technological constraints of WSI. Overall, the thesis concludes that WSI offers significant potential for the implementation of low-cost fine-grain parallel processing computer systems. However, due to the dual constraints of thermal management and the area required for the power distribution network, power density is a major design constraint in WSI. Indeed, it is shown that WSI power densities need to be an order of magnitude lower than VLSI power densities. The thesis demonstrates that for associative memories at least, VLSI designs are unsuited to implementation in WSI. Rather, it is shown that WSI circuits must be closely matched to the operational environment to assure suitable power densities. These circuits are significantly larger than their VLSI equivalents. Nonetheless, the thesis demonstrates that by concentrating on the most power intensive circuits, it is possible to achieve acceptable power densities with only a modest increase in area overheads.

Water scarcity combined with an increasing world population is creating pressure to develop new methods for producing food using less water. Rice is a staple crop with a very high water demand. This study examined the success in maintaining yields under water-saving irrigation management, including alternate wetting and drying (AWD). A meta-analysis was conducted examining yields under various types of water-saving irrigation compared to control plots kept under continuous flooding. The results indicated that yields can indeed be maintained under AWD as long as the field water level during the dry cycles is not allowed to drop below -15 cm, or the soil water potential is not allowed to drop below -10 kPa. Yields can likewise be maintained using irrigation intervals of 2 days, but the variability increases. Midseason drainage was not found to affect yield, though non-flooded conditions when maintained throughout most of the crop season appeared to be detrimental to yields. Increasingly negative effects on yields were found when increasing the severity of AWD or the length of the drainage periods. Potential benefits and drawbacks of water-saving irrigation management with regards to greenhouse gas emissions, soil quality and nutrient losses were discussed to highlight the complexity of the challenges of saving water in rice production.