Migrating freshwater fish population has been significantly declined, mostly by the obstruction of their migratory routes by hydropower dams. To diminish such impacts, fish ladders have been developed to facilitate the passage of migrating fish. However, fish ladders are associated with mortality and migratory failure, resulting in an ecological problem which has been a concern for years. The paper contained in the following pages focuses on studying the viability of an innovative modular design for a fish ladder developed by Fiskvägsteknik AB. The design is based in a vertical slot fishway (VSF) to which some roughness elements are attached to modify the flow. The aim of this bypass system is to restore the original biological continuity and diversity in the Swedish rivers, therefore solving a long-lasting ecological problem that hydroelectric production has caused over the years. Through a computational analysis, the flow has been evaluated as a function of the parameters that present an influence over its behaviour. First, a study of the changes in flow velocity influenced by four different slopes: 5 %, 10 %, 15 % and 20 %, has been performed with the objective to find an appropriate inclination according to the capabilities of the fish species considered. The lowest slopes have resulted to be the most appropriate ones, coinciding with low values of turbulent kinetic energy and lower flow velocities. The second step has been checking the effect of roughness elements on the bottom part of the structure tilted a 5%. The flow velocity has shown a considerable decrease, falling in the range of the fish swimming capabilities established. As for the streamlines of the flow, they were altered compared to the cases without the roughness elements.

Rock grouting is a commonly used process for sealing rocks in tunnels to reduce water ingress. In order to achieve sufficient sealing level the grout must effectively penetrate into rock fractures while the limiting factor is filtration of cement based grout. Many devices and measuring methods have been developed to study filtration and to measure the penetrability. The filter pump and the penetrability meter are two of the most commonly used instruments for measuring filtration tendency in the field and in the lab, while short slot is used mainly in the lab. The results obtained from these devices have relatively different estimations of the penetrability partly due to the weaknesses in measuring methods and test procedures. Furthermore, there are no clear criteria to find out which of the results are closer to the reality or how much the results differ among these instruments. The aim of this study is comparing, and evaluating the results of these devices in relatively similar conditions while using more accurate methods of weight-time and pressure-time compared to the less reliable total volume method. The filter pump and the penetrability meter were modified In order to fulfill the requirement of testing in similar conditions and to improve their accuracy and versatility. The results show that increasing the pressure improves the penetrability significantly. The modification of the filter pump results in reducing many uncertainties related to the testing procedure. Probably the modified filter pump has higher accuracy in measuring the penetrability compared to regular filter pump. The short slot has the highest accuracy in estimating penetrability of cement based grout especially at higher pressures, furthermore, the short slot provides a more flexible way to measure penetrability with different pressures in the range of 1-15 bars.

This paper considers the allocation of slots for a network of coordinated (congested) airports, where the term “slot” refers to a time on a specific day when a carrier is given permission to use the full range of airport infrastructure for the purpose of landing and take-off at a slot-controlled airport. We take into account the existing IATA rules and guidelines: priorities of requests for slots, the capacity limitations at each airport, the minimal turnaround time between arrival and subsequent departure of the same aircraft, and allocation to series of slots rather than to individual slots. Given the complexity of the problem, we propose an approach that consists of (i) a constructive heuristic procedure to generate a feasible and coherent allocation of slots for each airport from the network, and (ii) an iterative heuristic to improve the quality of an initial feasible solution in terms of the schedule delay (time difference between allocated time slots and airline requests). To evaluate whether the approach would be practical in real operation, we perform tests on a set of generated benchmark instances that span an entire scheduling season. The instances differ by the number of airports in the network and by the distribution of requests among airports from a given network - the largest number of airports forming a network is 100, while the maximum total number of aircraft movements considered on a half-yearly basis exceeds . We provide computational comparisons with solutions obtained when each airport from a network is considered independently (the en-route constraint is ignored). These results reveal that the consideration of the en-route constraint, which ensures a coherent allocation of slots at origin and destination airports, introduces only a minor degradation in the schedule delay and in the number of unaccommodated requests. Furthermore, we investigate the heuristic performance for reduced-capacity scenarios.

Endwall contouring has been widely studied as an effective measure to improve aerodynamic performance by reducing secondary flow strength. The effects of endwall contouring with discrete holes and an upstream purge slot for a high turning (127") airfoil passage under transonic conditions are investigated. The total pressure loss and secondary flow field were measured for two endwall geometries. The non-axisymmetric endwall was developed through an optimization study [1] to minimize secondary losses and is compared to a baseline planar endwall. The blade inlet span increased by 13 degrees with respect to the inlet in order to match engine representative inlet/exit Mach number loading in a HP turbine.  The experiments were performed in a quasi-2D linear cascade with measurements at design exit Mach number 0.88 and incidence angle. Four cases were analyzed for each endwall -- the effect of slot presence (with/without coolant) and the effect of discrete holes (with/without coolant) without slot injection. The coolant to mainstream mass flow ratio was set at 1.0% and 0.25% for upstream purge slot and discrete holes, respectively.  Aerodynamic loss coefficient is calculated with the measured exit total pressure at 0.1 Cax downstream of the blade trailing edge. CFD studies were conducted in compliment. The aero-optimized endwall yielded lower losses than baseline without the presence of the slot. However, in presence of the slot, losses increased due to formation of additional vortices. For both endwall geometries, results reveal that the slot has increased losses, while the addition of coolant further influences secondary flow development. / Master of Science

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The research aims to investigate how the 2D slot game “Lucky Hero”, created for this research, could convey the story of Beowulf. The result of this study could provide experience and strategy for improving narrative design in casual games with similar mechanics. Also, this study is valuable to developers/designers who want to explore the potential of using casual games, especially slot games, as a storytelling tool. To answer the research question “How could the 2D slot game Lucky Hero convey the story of Beowulf”, a “research for design” qualitative study was conducted. The researchers examined theories related to narrative design, design in slot machine games, and folk mythology to develop the game. Playtests followed by interviews and adapted stimulation recall were used as data collection methods, and thematic analysis was used as the data analysis technique. The findings revealed that the existing design of "Lucky Hero" was not capable of effectively conveying the story of Beowulf to players. However, the study identified key elements that influenced players' understanding, such as graphics and game mechanics. The future narrative design of “Lucky Hero” should focus on improving immersion, character representation, and the connection between game mechanics and the story.

In 2013, cracks were found in the radius of the dovetail slots of the rotor rim sheets in generator 1 of Juktan hydro power plant in Västerbotten, Sweden. The cracks were estimated to be too deep to be able to repair and Alstom conducted an investigation on the cause of fracture. The investigation came to the conclusion that the radius was too small and that the new rotor rim sheets should have a six times greater fillet radius. However, it has not been investigated whether the material structure or the manufacturing process may have an impact on the crack initiation and following propagation that is the focus of this report.Parts of the dovetail slots were cut out and characterized with XRF, SEM and LOM. Further mechanical characterizations were done according to Vickers.From the SEM and LOM micrographs a high amount of large (10μm) and cubic particles were found in the microstructure. The micrographs also showed a deformation of the microstructure and the hardness test showed a deformation hardening near the edge where the sheet had been punched. The edge surface of the sheet also had notches.The large and hard particles in the microstructure impair the mechanical properties of the steel. Furthermore, the hardening effect combined with the notches will make a good crack initiation point. Therefore, there is a higher possibility that a crack will initiate in the radius of the dovetail slots where large stresses occur.

This thesis examines how members of a Muslim community (made up of migrants and their descendants from various parts of North Africa, West Africa, Turkey, and elsewhere) in a small town in France seek to become moral persons through Islam. I argue that this quest for moral recognition is informed simultaneously by Islamic and French Republican values, which my French Muslim interlocutors usually conceive of as being consistent with one another. I contrast this analysis with other scholarly approaches to Islam in France that have generally explored the way non-Muslims perceive Islam to be at odds with Frenchness, how Muslims are marginalized and kept from becoming full citizens, and how certain public figures challenge and resist that oppression through explicit forms of resistance. I argue that these accounts, by focusing on Muslims seeking political recognition (from the state) in the face of oppression, have failed to account for the life projects of French Muslims, like my interlocutors, who emphasize moral over political considerations. In contrast to previous approaches, I follow my interlocutors' lead in analyzing the ways in which they seek after moral personhood and recognition as moral persons in their everyday discourse and practice. Thus, I show how an understanding of the moral projects of French Muslims is key to moving beyond a focus on suffering, oppression, and resistance in scholarship examining the experiences of migrants in France.

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