This thesis deals with energetical and efficiency comparison of two tractor transmission types, used by the Zetor company. The description of transmission construction types of various tractor producers is given, with focus on Zetor tractors transmission construction. The laboratory methodology and operating tractor and tractor sets measurement is described. The individual results are introduced in tables and graphs and subsequently evaluated.

This thesis describes fundamental approaches to quantify rate versus power consumption tradeoffs for cascaded communication systems. The discussion is bolstered by a large number of in-situ channel measurements, which are used in discussions of the power consumption of future massively broadband cellular systems. Chapter one provides an introduction. Chapter two discusses power consumption trends in modern communication systems. Chapter three introduces the consumption factor framework. Chapter four discusses the channel measurement campaign. Chapter five concludes the thesis, and uses the measurement results to estimate power consumption and capacity of future cellular systems. In addition, chapter five extends the consumption factor theory and draws fundamental conclusions about the energy price per bit for a general cascaded communication system. / text

The UK building stock accounts for about half of all energy consumed in the UK. A large portion of the energy is consumed by nondomestic buildings. Offices and retail are the most energy intensive typologies within the nondomestic building sector, typically accounting for over 50% of the nondomestic buildings’ total energy consumption. Heating, ventilating and air conditioning (HVAC) systems are the largest energy end use in the nondomestic sector, with energy consumption close to 50% of total energy consumption. Different HVAC systems have different energy requirements when responding to the same building heating and cooling demands. On the other hand, building heating and cooling demands depend on various parameters such as building fabrics, glazing ratio, building form, occupancy pattern, and many others. HVAC system energy requirements and building energy demands can be determined by mathematical modelling. A widely accepted approach among building professionals is to use building energy simulation tools such as EnergyPlus, IES, DOE2, etc. which can analyse in detail building energy consumption. However, preparing and running simulations in such tools is usually very complicated, time consuming and costly. Their complexity has been identified as the biggest obstacle. Adequate alternatives to complex building energy simulation tools are regression models which can provide results in an easier and faster way. This research deals with the development of regression models that enable the selection of HVAC systems for office buildings. In addition, the models are able to predict annual heating, cooling and auxiliary energy requirements of different HVAC systems as a function of office building heating and cooling demands. For the first part of the data set development used for the regression analysis, a data set of office building simulation archetypes was developed. The four most typical built forms (open plan sidelit, cellular sidelit, artificially lit open plan and composite sidelit cellular around artificially lit open plan built form) were coupled with five types of building fabric and three levels of glazing ratio. Furthermore, two measures of reducing solar heat gains were considered as well as implementation of daylight control. Also, building orientation was included in the analysis. In total 3840 different office buildings were then further coupled with five different HVAC systems: variable air volume system; constant air volume system; fan coil system with dedicated air; chilled ceiling system with embedded pipes, dedicated air and radiator heating; and chilled ceiling system with exposed aluminium panels, dedicated air and radiator heating. The total number of models simulated in EnergyPlus, in order to develop the input database for regression analysis, was 23,040. The results clearly indicate that it is possible to form a reliable judgement about each different HVAC system’s heating, cooling and auxiliary energy requirements based only on office building heating and cooling demands. High coefficients of determination of the proposed regression models show that HVAC system requirements can be predicted with high accuracy. The lowest coefficient of determination among cooling regression models was 0.94 in the case of the CAV system. HVAC system heating energy requirement regression models had a coefficient of determination above 0.96. The auxiliary energy requirement models had a coefficient of determination above 0.95, except in the case of chilled ceiling systems where the coefficient of determination was around 0.87. This research demonstrates that simplified regression models can be used to provide design decisions for the office building HVAC systems studied. Such models allow more rapid determination of HVAC systems energy requirements without the need for time-consuming (hence expensive) reconfigurations and runs of the simulation program.

Dans le courant de la théorie culturelle de la consommation (CCT), cette thèse explore la relation du consommateur à son système de consommation et s’emploie à décrire sous quelle forme de valorisation le consommateur l’exploite dans l’expérience. La première partie, qualitative, s’attache à explorer la nature de la relation du consommateur à son système d’objets (la garde-robe dans notre cas) à travers une étude anthropologique et une étude sémiotique réalisées durant les phases d’utilisation (filmées, photographiées et retranscrites) des systèmes de consommation. La seconde partie, quantitative, explore la sédimentation de valeur propre à l’exploitation d’un système au cours de différentes expériences de consommation : l’utilisation et le magasinage, envisagées dans le prêt-à-porter. Les résultats montrent une valorisation du système associée à la composante organisationnelle (traditionnellement décrite comme utilitaire) de la valeur à travers la recherche d’attributs d’interopérabilité des produits entre eux. Trois instruments de mesure sont adaptés et exploités dans une proposition de typologie. Nos données nous autorisent à valider la fiabilité des instruments de mesure adaptés et à identifier une typologie croisée de profils de magasinage et d’utilisation. / Within the course of the theory of cultural consumption (CCT), this research aims to enlighten on the relationship between the consumer to hir or her system of consumption. The first part, qualitative, attempts to describe the nature of the relationship between the consumer and his or her system (the wardrobe in our case) through an anthropological study and a semiotic study. The data was collected by way of observation (video and audio taped) during usage experiences. The second part, quantitative, measures separately the sedimentation of value linked to usage and shopping experiences. Applied to the clothing market, results show the value of the organisational and systemic concerns (which merges with the utilitarian aspects of value). Three tools are adapted and applied in order to construct a segmentation of consumers. The data allows us to confirm the reliability of our measurement scales and to suggest typologies based on usage and shopping, experiences which underlines the real link between the two consumption experiences as long as we take into account the system of consumption.