A Tilt-Wing Unmanned Aerial Vehicle (TW-UAV) and the preliminary evaluation of its hovering characteristics in extended simulation studies and experiments are presented in this Master Thesis. In the beginning, an overview of the TW-UAV's design properties are established, highlighting the novelties of the proposed structure and the overall merits. The TW-UAV's design and structural properties are mathematically modelled and utilized for the synthesis of a cascaded P-PI and PID based control structure for the regulation of its hovering performance. In addition, extensive simulation trials are performed in order to evaluate the structure's efficiency in controlling the TW-UAV's attitude and position under various noise and disturbance scenarios. The model and aircraft are then put through experimental evaluation with an on-board processor, namely the KFly, in a Motion-capture equipped laboratory to evaluate the control structure and physical behaviour of the TW-UAV. The results of these experiments are presented and discussed. The system and control scheme are shown to work well. However, an unfortunate crash forced the premature termination of experimentation and thus the conclusion of this thesis. Nevertheless, the reason for the crash is understood and discussed for future work.

This diploma thesis describes the design of winglets for LS-3 glider. The method for determination of main winglet parameters based on selected criterion is presented as well as comparation of performace of original wing and final modification. It also includes analysis of wing loading and resetting of speed and weight limits for flying with winglets.

As populism in Europe is on the rise there are two sides of populism contesting to make an impact on their societies. In connection with existing research, this study is focusing on the most prominent left-wing populist party in Spain, Podemos, and the  most prominent right-wing populist party in Italy, Lega Nord, and examines differences in their voters’ attitudes regarding a couple of crucial indicators of populism. The study is influenced by a previous study that examined the attitudes of left-wing and right-wing voters. The main distinction between this previous study and the current one is that my study also includes voters from the Spanish left-wing party Podemos, which was not included in the previous research. The result of my study show that Podemos voters are more positive towards the EU and towards immigration in difference to Lega Nord voters, whereas they have comparable attitudes towards material deprivation and elitism.

The purpose of this study is to examine right-wing alternative media's framing of politics. This is examined by applying a method based on the framing theory, called Issue, game and scandal. The material consists of political news articles from these media during the 2018 election campaign in Sweden (13 August to 9 September), which in turn are either classified as issue news, game news or scandal news. The study uses the following five sites: Samhällsnytt, Nya Tider, Samtiden, Nya Dagbladet and Nyhetsbyrån. The study shows that alternative right-wing media frame politics as a scandal most times, followed by game and then issue. The results from the study are then compared with traditional media's framing of politics during the same period of time, where it shows that alternative right-wing media frame politics as scandal to a much greater degree than traditional media do, and that issue and game framings occur significantly less often on alternative right-wing media. The study also tries to explain how the differences between alternative right-wing media and traditional media can be understood, where press ethics and populism seem to be the key attributes. / Syftet med denna uppsatsen är att undersöka alternativa högermediers gestaltning av politik. Detta undersöks genom att applicera en metod som baseras på gestaltningsteorin - Sak, spel och skandal. Materialet består av politiska nyhetsartiklar från dessa medier under den svenska valrörelsen 2018 (13 augusti till 9 september), som i sin tur antingen klassificeras som saknyhet, spelnyhet eller skandalnyhet. I undersökningen används följande fem sajter: Samhällsnytt, Nya Tider, Samtiden, Nya Dagbladet och Nyhetsbyrån. Undersökningen visar att alternativa högermedier gestaltar politik som skandal flest gånger, följt av spel och sen sak. Resultatet från undersökningen jämförs sedan med traditionella mediers gestaltning av politik under samma tidsperiod, där det framgår att alternativa högermedier gestaltar politik som skandal i betydligt högre grad än vad traditionella medier gör, samt att sak- och spelgestaltningar förekommer betydligt färre gånger på alternativa högermedier. Dessutom redogörs det för hur skillnaderna mellan alternativa högermedier och traditionella medier kan förstås, där pressetik och populism bidrar med förklaringen.

No description available.

The purpose of this study is to examine the multidisciplinary design optimization (MDO) of a distributed propulsion blended-wing-body (BWB) aircraft. The BWB is a hybrid shape resembling a flying wing, placing the payload in the inboard sections of the wing. The distributed propulsion concept involves replacing a small number of large engines with many smaller engines. The distributed propulsion concept considered here ducts part of the engine exhaust to exit out along the trailing edge of the wing. The distributed propulsion concept affects almost every aspect of the BWB design. Methods to model these effects and integrate them into an MDO framework were developed. The most important effect modeled is the impact on the propulsive efficiency. There has been conjecture that there will be an increase in propulsive efficiency when there is blowing out of the trailing edge of a wing. A mathematical formulation was derived to explain this. The formulation showed that the jet "fills in" the wake behind the body, improving the overall aerodynamic/propulsion system, resulting in an increased propulsive efficiency. The distributed propulsion concept also replaces the conventional elevons with a vectored thrust system for longitudinal control. An extension of Spence's Jet Flap theory was developed to estimate the effects of this vectored thrust system on the aircraft longitudinal control. It was found to provide a reasonable estimate of the control capability of the aircraft. An MDO framework was developed, integrating all the distributed propulsion effects modeled. Using a gradient based optimization algorithm, the distributed propulsion BWB aircraft was optimized and compared with a similarly optimized conventional BWB design. Both designs are for an 800 passenger, 0.85 cruise Mach number and 7000 nmi mission. The MDO results found that the distributed propulsion BWB aircraft has a 4% takeoff gross weight and a 2% fuel weight. Both designs have similar planform shapes, although the planform area of the distributed propulsion BWB design is 10% smaller. Through parametric studies, it was also found that the aircraft was most sensitive to the amount of savings in propulsive efficiency and the weight of the ducts used to divert the engine exhaust. / Ph. D.

The purpose of the study was to evaluate the merits of the DiscRotor concept that combine the features of a retractable rotor system for vertical take-off and landing (VTOL) with an integral, circular wing for high-speed flight. Tests were conducted to generate basic aerodynamic characteristics of the DiscRotor in hover and in fixed-wing flight. To assess the DiscRotor during hover, small scale tests were conducted on a 3ft diameter rotor without the presence of a fuselage. A "hover rig" was constructed capable of rotating the model rotor at speeds up to 3,500 RPM to reach tip speeds of 500fps. Thrust and torque generated by the rotating model were measured via a two-component load cell, and time averaged values were obtained for various speeds and pitch angles. It has been shown that the DiscRotor will perform well in hover. Ground Effects in hover were examined by simulating the ground with a movable, solid wall. The thrust was found to increase by 50% compared to the ground-independent case. Pressure distributions were measured on the ground and disc surfaces. Velocity measurements examined the flow field downstream of the rotor by traversing a seven hole velocity probe. A wake behind the rotor was shown to contract due to a low pressure region that develops downstream of the disc. Wind tunnel experimentation was also performed to examine the fixed wing flight of the DiscRotor. These experiments were performed in the VA Tech 6â X6â Stability Tunnel. A model of the fuselage and a circular wing was fabricated based upon an initial sizing study completed by our partners at Boeing. Forces were directly measured via a six degree of freedom load cell, or balance, for free stream velocities up to 200fps. Reynolds numbers of 2 and 0.5 million have been investigated for multiple angles of attack. Low lift-to-drag ratios were found placing high power requirements for the DiscRotor during fixed-wing flight. By traversing a seven-hole velocity probe, velocities in a 2-D grid perpendicular to the flow were measured on the model. The strengths of shed vortices from the model were calculated. A method to improve fixed-wing performance was considered where two blades were extended from the disc. An increase of 0.17 in the CL was measured due to the interaction between the disc and blades. This research utilized a wide range of experiments, with the aim of generating basic aerodynamic characteristics of the DiscRotor. A substantial amount of quantitative data was collected that could not be included in this document. Results aided in the initial designs of this aircraft for the purpose of evaluating the merit of the DiscRotor concept. / Master of Science

No description available.

This study utilizes Multidisciplinary Design Optimization (MDO) techniques to explore the effectiveness of the truss-braced (TBW) and strut-braced (SBW) wing configurations in enhancing the performance of medium range, transonic transport aircraft. The truss and strut-braced wing concepts synergize structures and aerodynamics to create a planform with decreased weight and drag. Past studies at Virginia Tech have found that these configurations can achieve significant performance benefits when compared to a cantilever aircraft with a long range, Boeing 777-200ER-like mission. The objective of this study is to explore these benefits when applied to a medium range Boeing 737-800NG-like aircraft with a cruise Mach number of 0.78, a 3,115 nautical mile range, and 162 passengers. Results demonstrate the significant performance benefits of the SBW and TBW configurations. Both configurations exhibit reduced weight and fuel consumption. Configurations are also optimized for 1990's or advanced technology aerodynamics. For the 1990's technology minimum TOGW cases, the SBW and TBW configurations achieve reductions in the TOGW of as much as 6% with 20% less fuel weight than the comparable cantilever configurations. The 1990's technology minimum fuel cases offer fuel weight reductions of about 13% compared to the 1990's technology minimum TOGW configurations and 11% when compared to the 1990's minimum fuel optimized cantilever configurations. The advanced aerodynamics technology minimum TOGW configurations feature an additional 4% weight savings over the comparable 1990's technology results while the advanced technology minimum fuel cases show fuel savings of 12% over the 1990's minimum fuel results. This translates to a 15% reduction in TOGW for the advanced technology minimum TOGW cases and a 47% reduction in fuel consumption for the advanced technology minimum fuel cases when compared to the simulated Boeing 737-800NG. It is found that the TBW configurations do not offer significant performance benefits over the comparable SBW designs. / Master of Science

The ongoing war in Ukraine and Gaza have sparked international discussion on how to manage the situation but also on which side one should stand in these conflicts. One axis ofsupport these discussions occur are along ideological lines. What this paper aims to achieve is to understand where the left- and right-wing stand in these conflicts and what kind of reasonings that they put forwards to justify their support. In order to come to a conclusion this paper will use a text analysis method on different ideologically charged text in form of debate articles, policy documents and other public statements from four Swedish parties, two on the left and two on the right. This method will be a qualitative idea analysis that will focuson different statements from these texts that will then be analyzed and interpreted throughan IR constructivist lens. What could be concluded from this paper was a clear result that all four parties were on the side of Ukraine but differed on the Israel-Palestine with the right-wing leaning more to Israel and the left-wing leaning towards Palestine. This because two of the parties were more in the center of the ideological divide while two of them were on clear opposite sides with the more socialist party siding with Palestine due to principal and historical support while the more conservative party sided with Israel due to clear outspoken support and ideological similarities with the ruling party of Israel.