Dans ces travaux de thèse, nous proposons de nouvelles méthodes d’estimation de canal pour un système full-duplex dédié aux communications véhiculaires. Les deux canaux relatifs au signal utile (SOI) et au signal interférant (SI) sont estimés. Les méthodes que nous proposons sont classées selon si les pilotes des deux signaux sont envoyés séparément ou simultanément. Dans le cas de la transmission séparée des pilotes, nous proposons un algorithme se basant sur un positionnement dynamique des pilotes ainsi qu’une méthode hybride qui combine l’approche du changement de position des pilotes avec l’emploi des séquences d’apprentissage en début de trame. Nous proposons également une méthode visant à optimiser l’estimation classique qui se base sur un séquence d’apprentissage en amélioration l’estimation au niveau de chaque symbole préambule. Dans le contexte d’une transmission simultanée des pilotes, nous proposons deux algorithmes visant à améliorer les performances d’estimation par rapport aux méthodes existantes. Dans la première méthode proposée, les deux canaux SI et SOI sont estimés dans le domaine fréquentiel à l’aide des itérations de Landweber. La seconde proposition consiste à utiliser une matrice de projectionafin d’éviter le bruit engendré par les données inconnues du signal SOI lors de l’estimation. Finalement, nous proposons une méthode d’estimation de canal sélectif en temps et en fréquence pour des fréquences doppler faibles à modérées. Certaines méthodes proposées sont implémentées dans un système full-duplex expérimental qui a recours aux antennes reconfigurables pour réaliser l’annulation passive. / In this work of thesis, we propose new channel estimation approaches for a full-duplex system dédicated to vehicular communications. Both the self-interference (SI) and intended (SOI) channel are estimated. We propose different estimation méthods according to whether the pilots of the signals are transmitted jointly or separately. In the separate transmission, an estimation based on a new pilot configuration is proposed as well as a hybrid method which use both pilot configuration and training sequences.We also propose an optimisation of the conventional training-based method.It consists of improving the estimation of each training symbole. In the joint transmission, we propose two algorithms that aims to improve the estimation performances compared to the existing methods. In the first proposed method, the two channels are first estimated in the frequency domain using the Landweber iterations. The second proposition consists of using a projection matrix to manipulate only the pilots and avoid the noise that is caused by the SOI unknown datas. Finally, we propose a time and frequency-selective channel estimation for low and medium doppler frequency. Some of the proposed estimators are implemented on a real Full Duplex communication system which use Multi-reconfigurable antennas to perform the passive cancellation.

The Municipality of Quelimane, the fourth biggest city in Mozambique, aims to apply an EcoCity concept in the city. Therefore, the municipality initiated a waste-to-energy project in order to improve the lacking waste management, valorize resources and lessen the burden on the environment. The purpose of the current project was to investigate the potential for implementing a waste-to-energy system in Quelimane. In particular, the technology of anaerobic digestion. This technology had been identified as the best alternative based on local conditions according to a study performed by students at KTH, the municipality of Quelimane and GreenLight about waste-to-energy in Quelimane the spring of 2015. The present project was performed during eight weeks in Mozambique; five weeks in the capital Maputo and three weeks on-site in Quelimane, where the collection of data mainly was made in Quelimane. The gathered information resulted in a model for a small scale anaerobic digestion system in Quelimane. An assessment of the potential for an implementation of an anaerobic digestion system in Quelimane was determined using a feasibility assessment tool. The study was performed using the following methods: literature study, interviews, surveys, on-site observations, modelling and by using a feasibility assessment tool. The analysis performed with the feasibility tool identified the socio-cultural attitude towards the technology and the willingness among the residents to use the end products as key factors for a successful implementation. The attitude towards the technology was determined as mainly positive and the willingness to use the end product high. The strong involvement and initiative from the municipality were also identified as key factors and determined as positive. The environmental, policy and legal and the technological aspects of the system are other identified key factors were mainly identified as positive according to the feasibility assessment tool. However, there is currently no end user for the small scale plant and no established funding for the project. This altogether results in a current marginally high potential for the implementation of a small scale anaerobic digestion plant, with good chances to increase the potential in the future.

<p>Emergency services (ES) pilots operate in a dynamic, high-risk team environment, as a subset of general aviation (GA) operations. The time constraints associated with ES operations means that ES pilots must make flight decisions quickly and often with limited or incomplete information (Worm, 1999). Due to the nature of ES operations, the consequences of an incorrect flight decision can be severe, including loss of life. ES operations are often initiated by extreme weather events, and ES pilots are frequently required to fly on the boundary between marginal visual flight rules (MVFR) weather conditions and instrument meteorological conditions (IMC). Unfortunately, an unintended transition into IMC is the leading cause of fatal accidents in GA operations (Ayiei et al., 2020). Mission objectives dictate that most ES pilots fly below 1,500’ above ground level (AGL) for extended periods of time, and low-altitude flight in hazardous weather can reduce a pilot’s outside visual reference, thus leading to spatial disorientation, loss of control, or controlled flight into terrain. To mitigate this problem, ES pilots must be able to accurately assess weather conditions before and during flight. However, the current method of presenting meteorological aerodrome reports (METARs) on weather displays can be misleading to pilots. Weather conditions in the areas between weather observation stations can be different than what is reported by the METAR observations at those stations. This can cause current or forecasted weather conditions <em>between</em> weather stations to be incompletely represented. However, pilots are given no obvious indication of how incompletely represented weather conditions can affect weather-related risk. This research demonstrates that a <em>Kth</em> Nearest Neighbor (KNN) analysis can be used to identify areas where the variability of conditions between weather stations (and thus weather-related risk) is incompletely represented by METAR observations. In addition, it is shown that areas where there is an increased risk of an unintended transition from MVFR to IMC can be identified among areas with incompletely represented conditions and depicted to pilots on aviation weather displays. Machine learning tactics are proposed as a way to consider additional inputs in future KNN analyses, and several emerging technologies are proposed as mediums to collect additional weather observations. The ability for an ES pilot to more accurately assess weather-related risk in MVFR conditions using the proposed technologies is evaluated, the benefits to ES pilots and the GA community are discussed, and the requirements and limitations of the study are examined.</p>

While worldwide the flight industry was increasing in the last decade, little is known about the working environment of pilots and flight attendants. This paper aims to develop a deeper understanding based on the theories of loyalty, self-loyalty, commitment, and motivation for pilots and flight attendants in the low-cost segment and the carrier segment in the flight industry. A qualitative study with a semi-structured interview is provided. In total, three pilots and three flight attendants who work for a low-cost airline and carrier airlines from all over the world were interviewed. The findings show that a differentiation between before the COVID 19 pandemic and during COVID 19 has to be made. Before COVID 19, pilots were almost satisfied with their working conditions whereas flight attendants felt their working conditions could have been improved in terms of better wages. However, during the COVID 19 time, both the flight attendants and pilots are afraid of losing their job. Due to COVID 19, many flights were cancelled which might have an impact on the flight industry in the future. My studies open up possibilities for new research in the future about the transformation of the flight industry after COVID 19.

Zum Ende der Förderung durch die Förderlinie „Lehrpraxis im Transfer“ wurde eine Pilotstudie zur datengestützten Lernanalyse (Learning Analytics) durchgeführt, die das Potenzial der SHRIMP Plattform für diese Form der Auswertung erkunden sollte. Vorgehen und Ergebnisse dieser Pilotstudie sind in diesem Paper kurz dokumentiert.:1. Einleitung 2. Methodik und Daten 3. Analyse 4. Zusammenfassung 5. Gründe und Ansätze für eine weiterführende, datengestützte Analyse von SHRIMP

Reducing energy consumption in pulp and paper refining requires a deep understanding of all the processes involved. This dissertation investigates fundamental mechanics of the low consistency mechanical refining process. Three studies investigate forces applied to wood fibers with the focus on how force profiles during bar passing events change with process variables such as fiber length and refiner load. In the first study a high resolution rotary encoder and a piezo ceramic force sensor are implemented in a 16-inch laboratory-scale low consistency refiner to explore the effect of plate gaps on bar-force profiles. The rotary encoder data is used to locate the rotor bars relative to the stator bar in which the sensor is located. Force profiles for bar passing events are registered to the position of rotor bars relative to the stator bar in which the sensor is located and mean force profiles are produced. These mean force profiles have potential to shed light on the fundamental mechanisms of mechanical refining. For large gaps, there is a late peak in the force profiles that occurs toward the end of the bar passing event. For gaps that are less than the critical gap, below which fiber cutting occurs, there is an early peak in the force profiles that occurs at the start of the bar passing event. It is hypothesized that the early peak represents the corner force and, therefore, that corner force is causal in the onset of fiber cutting. In the second study a set of piezo ceramic force sensors is implemented in a 52-inch mill-scale low consistency refiner to explore the effect of varying operating conditions on bar force profiles. Force profiles for individual bar passing events are identified based on key features in the time domain force data based on the knowledge acquired from the previous study in the pilot-scale refiner. The individual bar force profiles are classified as single peak events which feature one peak corresponding to the fiber compression force and as dual peak events corresponding to fiber compression force and the corner force. It is shown that dual peak events which are considered to represent the corner force, are present throughout the whole range of refining and increase with increased refining energy. After applying the dual peak analysis to the data from the previous study this behaviour was also found in the pilot-scale refiner data. Furthermore, it is found that different radial positions on the stator plate are subjected to different force profiles. This is thought to be due to the difference in tangential speed and a change in the fiber and floc material properties at different radial positions. In the third study the effect of refiner plate wear on bar force sensor measurements is explored by applying the dual peak analysis to long term data acquired from the mill-scale refiner. Bar passing events are analysed based on the dual peak ratio and the timing of the early peak in the dual peak events. Force measurements are evaluated over the full run time of a set of refiner plates. When comparing force profiles with refiner plate wear measurements and discharge fiber analysis, it is found that the decrease in the prevalence of the corner force correlates with the wear of the leading edge of the refiner bars, or bar rounding, for the run time of the refiner plate. This is accompanied by a decrease in plate performance which is represented by a decrease in fiber length and freeness reduction for the same refiner load. / Graduate

Planning and management of logistics and material flow are widely studied and two key factors contributing to company competitiveness. Automation in material flow is recognized in efficient and profitable factories in the context of today’s smart industry, however, the operators are playing a significant role as well. The purpose of the study was to identify which criteria could be used to determine the level of automation in a material flow of the industrial factory. A model was developed to practically support the decision making on the level of automation for the case company that was going to build a pilot line for battery manufacturing. The question for the case company was to decide whether the process should be fully automated, manual, or semi-automated in its trial production to avoid costly reconfigurations when a full production starts. In this study a literature review was conducted in the form of previous research to describe which criteria were important to decide the level of automation. The literature study together with site visiting, interviews, survey and document analysis was used for the formulation of research questions, establishment of methodology and model development. The study has identified different criteria whereas six of them are shared by both literature studies and the case company. Two unique criteria were identified in the case company but not found in the literature: lead time and recruitment. The lead time refers to the time from planning to finished process and the recruitment is about how difficult to recruit people with the right skills. Two theoretical contributions presented in this study: new criteria when deciding on the level of automation and a model that assists in decisions regarding the level of automation in early phases. The model is also a practical contribution to the case company. Finally, some suggestions for further research within the area are presented.

The multi zone fluidized bed reactor instantaneously creates several chemical/physical environments in a single reactor vessel. Effective solid circulation across zones can be achieved by tuning the reactor geometries, solid properties, and operating conditions. However, there is limited research for this innovative reactor concept beyond the laboratory scale, among which a better understanding of the complex fluid dynamics, dominating the solid circulation in different zones, is a basis. This work aims to propose a new method to capture the fluid dynamics of a pilot MZFBR by laboratory measurements with validation from theoretical analysis and simulation. Toward this goal, we first performed particle characterizations, and fluidization testing experiments in a laboratory scale fluidized bed reactor and a pilot scale multi zone fluidized bed reactor at ambient conditions to study the development of fluidization regimes. Then we compared the minimum fluidization velocity with argon and air between the experimental measurements and theoretical calculation results and proposed a modified Ergun equation, which better fits our system. Finally, we conducted computational particle fluid dynamics simulations for the pilot multi zone fluidized bed reactor with the Ergun equation and our modified equation and compared the results against previous experimental observations. Simulations display that the prediction of pressure drop in the pilot scale multi zone fluidized bed reactor with the proposed Ergun equation is similar to that of the original equation, with a relative deviation of around 3%. However, the modified equation captured the bubbling fluidization behavior as the experiment, while the Ergun equation predicted a smooth fluidization without any bubbles. The better agreements validated both our workflow of estimating the fluidization behavior in a pilot multi zone fluidized bed reactor from laboratory measurements and the simulation strategy.

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A vast area of the northeastern Great Basin of the western USA was inundated by a succession of Plio-Pleistocene lakes, including Lake Bonneville (28 ka to 12 ka). The Pilot Valley playa, located just east of the Utah-Nevada border near Wendover, Utah, within the eastern Basin and Range Province, represents an 8 to 16 km wide and ~50 km long remnant of these lakes. The playa corresponds to the upper surface of a closed basin that is delimited by two mountain ranges, which are mantled by recent alluvial fans over which the playa sediments have prograded. In order to investigate the interaction of Plio- Pleistocene lake sedimentation and alluvial fan development, high-resolution seismic reflection profiles have been acquired near the base of both the west-bounding and the east-bounding ranges. On the western side of the basin, the seismic profiles provide images of sub-horizontal playa sediments prograding over the inclined alluvial fans. Theboundary between the playa and fan sediments is marked by a prominent angular unconformity. Seismic images from the eastern side of the basin reveal a markedly different structural and stratigraphic style with down-to-the-basin normal faulting of relatively shallow Paleozoic bedrock overlain by alluvial fan deposits, which are in turn on-lapped by a thin veneer of playa sediments. The results contained herein reveal for the first time the stratigraphic relationships between Quaternary pluvial sediments as a shoreline depositional facies and the adjacent bounding fan deposits. Post-stack reprocessing of lower-resolution but deeper penetration seismic data located in an analogous basin to the southwest, provides a likely context for the Pilot Valley seismic data. The new geophysical images, when integrated with available geologic mapping and limited well control, aid in constraining how deep aquifers are locally recharged from an adjacent range. The results also clearly demonstrate the strong structural asymmetry of the range and playa system, which is consistent with a classic half-graben structure. Lastly, this study demonstrates the utility of the shallow seismic reflection method as a tool to provide high-resolution sub-surface images in the geophysically challenging environment of Basin and Range geology.