Unmanned Aircraft Systems (UAS) face one common challenge when integrating with the existing manned aircraft population in the National Airspace System (NAS). To unlock the full efficiency of UAS, the UAS integrator must comply with an onboard pilot’s requirement to see-and-avoid other aircraft while operating. Commercially available Detect-and-Avoid (DAA) sensor technologies have been developed to attempt to comply with this requirement. UAS integrators must use these sensors to meet or exceed the performance of a human pilot. This thesis covers research done to integrate an array of commercially made DAA sensors with a large Group 3 UAS both in hardware and software that was later flight tested and evaluated for usability. A fast-time simulation is presented using the principles of the National Aeronautics and Space Administration's (NASA) Detect-and-AvoID Alerting Logic for Unmanned Systems (DAIDALUS). Last, open-source tools are presented to assist future integrators in validating their DAA solutions.

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Modern radar technology relies heavily on digital signal processing. As radar technology pushes the boundaries of miniaturization, computational systems must be developed to support the processing demand. One particular application for small radar technology is in modern drone systems. Many drone applications are currently inhibited by safety concerns of autonomous vehicles navigating shared airspace. Research in radar based Detect and Avoid (DAA) attempts to address these concerns by using radar to detect nearby aircraft and choosing an alternative flight path. Implementation of radar on small Unmanned Air Vehicles (UAV), however, requires a lightweight and power efficient design. Likewise, the radar processing system must also be small and efficient. This thesis presents the design of the processing system for a small Frequency Modulated Continuous Wave (FMCW) phased array radar. The radar and processing is designed to be light-weight and low-power in order to fly onboard a UAV less than 25 kg in weight. The radar algorithms for this design include a parallelized Fast Fourier Transform (FFT), cross correlation, and beamforming. Target detection algorithms are also implemented. All of the computation is performed in real-time on a Xilinx Zynq 7010 System on Chip (SoC) processor utilizing both FPGA and CPU resources. The radar system (excluding antennas) has dimensions of 2.25 x 4 x 1.5 in3, weighs 120 g, and consumes 8 W of power of which the processing system occupies 2.6 W. The processing system performs over 652 million arithmetic operations per second and is capable of performing the full processing in real-time. The radar has also been tested in several scenarios both airborne on small UAVs as well as on the ground. Small UAVs have been detected to ranges of 350 m and larger aircraft up to 800 m. This thesis will describe the radar design architecture, the custom designed radar hardware, the FPGA based processing implementations, and conclude with an evaluation of the system's effectiveness and performance.

For unmanned aircraft systems to gain full access to the National Airspace System (NAS), they must have the capability to detect and avoid other aircraft. This research focuses on the development of a detect-and-avoid (DAA) system for small unmanned aircraft systems. To safely avoid another aircraft, an unmanned aircraft must detect the intruder aircraft with ample time and distance. Two analytical methods for finding the minimum detection range needed are described. The first method, time-based geometric velocity vectors (TGVV), includes the bank-angle dynamics of the ownship while the second, geometric velocity vectors (GVV), assumes an instantaneous bank-angle maneuver. The solution using the first method must be found numerically, while the second has a closed-form analytical solution. These methods are compared to two existing methods. Results show the time-based geometric velocity vectors approach is precise, and the geometric velocity vectors approach is a good approximation under many conditions. The DAA problem requires the use of a robust target detection and tracking algorithm for tracking multiple maneuvering aircraft in the presence of noisy, cluttered, and missed measurements. Additionally these algorithms needs to be able to detect overtaking intruders, which has been resolved by using multiple radar sensors around the aircraft. To achieve these goals the formulation of a nonlinear extension to R-RANSAC has been performed, known as extended recursive-RANSAC (ER-RANSAC). The primary modifications needed for this ER-RANSAC implementation include the use of an EKF, nonlinear inlier functions, and the Gauss-Newton method for model hypothesis and generation. A fully functional DAA system includes target detection and tracking, collision detection, and collision avoidance. In this research we demonstrate the integration of each of the DAA-system subcomponents into fully functional simulation and hardware implementations using a ground-based radar setup. This integration resulted in various modifications of the radar DSP, collision detection, and collision avoidance algorithms, to improve the performance of the fully integrated DAA system. Using these subcomponents we present flight results of a complete ground-based radar DAA system, using actual radar hardware.

Robust communication is required to provide a safe airspace for the large numbers of unmanned aerial systems that are coming to the National Airspace System (NAS). This thesis explores methods for providing robust communication to large numbers of vehicles in the NAS. Automatic dependent surveillance-broadcast (ASD-B) is a transmission system that can transmit to and is currently required on all manned aircraft. Unfortunately, ADS-B suffers connectivity problems when supporting large numbers of unmanned aerial systems (UAS). The 5G Cellular protocol can support large numbers of UAS, but connectivity suffers with an increase in distance and interference. Using a 5G cellular and an ADS-B simulator we evaluate the advantages of a combined ADS-B and 5G Cellular transmission system compared to a 5G or ADS-B exclusive system. We also offer hybrid system recommendations that clarify the appropriate operation strategies or triggers that should prompt transitions between transmission systems in different environmental situations. The simulation results show message success and vehicle collision rates, with each messaging method investigated to show the case for a combined communication system. This study shows that a hybrid transmission system is a possible communication solution for UAS operating in beyond visual line of sight (BVLOS) environments.

The problem of aircraft conflict detection and resolution (CDR) in uncertainty is addressed in this thesis. The main goal in CDR is to provide safety for the aircraft while minimizing their fuel consumption and flight delays. In reality, a high degree of uncertainty can exist in certain aircraft-aircraft encounters especially in cases where aircraft do not have the capabilities to communicate with each other. Through the use of a probabilistic approach and a multiple model (MM) trajectory information processing framework, this uncertainty can be effectively handled. For conflict detection, a randomized Monte Carlo (MC) algorithm is used to accurately detect conflicts, and, if a conflict is detected, a conflict resolution algorithm is run that utilizes a sequential list Viterbi algorithm. This thesis presents the MM CDR method and a comprehensive MC simulation and performance evaluation study that demonstrates its capabilities and efficiency.

Stress hos sjuksköterskor är vanligt förekommande vilket kan påverka arbetsförmågan och leda till en försämring i omvårdandskvalitén. Arbetsklimatet gör att sjuksköterskor oavsett arbetslängd funderar över att lämna yrket alternativt valt att lämna. Samtidigt är det brist på sjuksköterskor i Sverige och majoriteten av arbetsgivare är i behov av att anställa sjuksköterskor på grund- och specialistnivå. Syftet med studien var att beskriva stresshanteringsmetoder för att minska arbetsrelaterad stress hos sjuksköterskor. Studien var en systematisk litteraturöversikt som inkluderat 24 studier som publicerats på engelska mellan 2010–2018 med hög och medel vetenskaplig kvalité. Resultatet identifierade tio stresshanteringsmetoder som kunde minska arbetsrelaterad stress och tre tillvägagångssätt påvisades. Reducera stressorer på arbetsplatsen; Organisationförändringar och utbildning i vård av äldre. Hitta metoder för att anpassa sig till stressfulla miljöer; Coping strategier. Interventioner med stresshanteringsmetoder; Avslappningsövningar, BREATHE, Mindfulness, PAR, Resilience training program, Self-help through mobile phone och Stressmanagement program. Sjuksköterskor kan möjligtvis stärka sitt empowerment med välvalda coping strategier där sjuksköterskan tar kontroll över sina handlingar och känslor. Förstärkning av begriplighet och hanterbarhet enligt Antonovskys teori om KASAM kan eventuellt stärkas med sex av stresshanteringsmetoder från resultatet. I syfte att stärka sjuksköterskors meningsfullhet bör gemensamma värderingar stärkas bland sjuksköterskor i olika arbetsgrupper. Meningsfullhet bidrar till motivation och engagemang samt gör att stress tolkas som utmaningar värda att investera energi i.

The master’s thesis expresses an opinion on trends in UAV integration into non-segregated airspace issue. In the beginning, barriers to integration are characterized and a broader context is shown. Since necessity of the technical realization of the “see and be seen” principle exists, requirements for so called Sense and Avoid systems are presented. Various methods of Sense and Avoid are briefly described, highlighting their contribution to air safety and their potential for future development. The UAV communication topic is described in the last chapter, providing a list of the volume of transmitted messages, analyzing data link frequencies and selecting appropriate means of UAV operations.

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-06-15T18:33:41Z No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-28T11:59:17Z (GMT) No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Made available in DSpace on 2016-06-28T11:59:17Z (GMT). No. of bitstreams: 2 Tese - Diogo Soares Menezes Samia - 2015.pdf: 4976311 bytes, checksum: 317908c75deb4de1770cd68c544a5190 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Optimal escape theory states that animals should counterbalance the costs and benefits of flight when escaping from a potential predator. However, in apparent contradiction with this well-established optimality model, birds and mammals generally initiate escape soon after beginning to monitor an approaching threat; a phenomena codified as the “Flush Early and Avoid the Rush” (FEAR) hypothesis. Typically, the FEAR hypothesis is tested using correlational statistics and is supported when there is a strong relationship between the distance at which an individual first responds behaviorally to an approaching predator (alert distance; AD), and its flight initiation distance (the distance at which it flees the approaching predator; FID). However, such correlational statistics are both inadequate to analyze relationships constrained by an envelope (such as that in the AD-FID relationship) and are sensitive to outliers with high leverage, which can lead one to erroneous conclusions. To overcome these statistical concerns we develop the phi index (Φ), a distribution-free metric to evaluate the goodness of fit of a 1:1 relationship in a constraint envelope (the prediction of the FEAR hypothesis). Using both simulation and empirical data, we conclude that Φ is superior to traditional correlational analyses because it explicitly tests the FEAR prediction, is robust to outliers, and it controls for the disproportionate influence of observations from large predictor values (caused by the constrained envelope in AD-FID relationship). Importantly, by analyzing the empirical data we corroborate the strong effect that alertness has on flight as stated by the FEAR hypothesis. / A teoria do escape ótimo afirma que os animais devem contrabalançar os custos e benefícios da fuga quando vão escapar de um predador. No entanto, em aparente contradição com este bem-estabelecido modelo ótimo, aves e mamíferos geralmente empreendem fuga logo após inicio do monitoramento do predador em potencial; um fenômeno denominado “Flush Early and Avoid the Rush hypothesis” (a hipótese FEAR). A hipótese FEAR é geralmente testada usando estatísticas correlativas e seu suporte se dá por uma forte relação positiva entre a distância na qual um indivíduo responde comportamentalmente a um predador que se aproxima (distância de alerta; alert distance, AD) e a distância do início da fuga (flight initiation distance, FID). No entanto, o uso de estatísticas correlativas para testar a hipótese FEAR pode levar a conclusões errôneas, já que estatísticas correlativas são inadequadas para análise de relações em envelope (tais como a relação entre AD e FID) e são sensíveis a valores discrepantes (outliers) com elevado efeito de alavancagem. Por isso, nós desenvolvemos o índice fi (Φ), uma métrica não-paramétrica destinada a avaliar a qualidade do ajuste de uma relação 1:1 restrita por um envelope (tal como a observada na hipótese FEAR). Usando simulações numéricas e dados empíricos, nós concluímos que Φ é uma métrica superior às análises de correlação tradicionais porque testa explicitamente a predição da hipótese FEAR, é robusta a outiliers, e ainda controla pela influência disproporcional dos altos de AD (causado pela relação em envelope entre AD e FID). Como predito pela hipótese FEAR, a análise dos dados empíricos corroborou o forte efeito que a distância de alerta tem sobre a decisão de fuga das presas.

Comparison liability of statutory representatives for company's debts in case of breach of the duty to strive to avoid insolvency and wrongful trading The aim of thesis is to compare liability of statutory representatives for company's debts in case of breach of the duty to strive to avoid insolvency and wrongful trading. The reason for choosing this topic was discussion which was last two years about extent of liability of statutory representatives for company's debts in case of breach of the duty to strive to avoid insolvency in Czech Republic. The work is divided into three chapters. Chapter one provides a general overview of the liability of statutory representatives for company's debts in case of breach of the duty to strive to avoid insolvency. It explains very wide extent of personal liability which the legislature provided not only to members of the boards of directions, but also the influential and controlling person Business Corporation. Furthermore, I analyze the enactment of the new duty to strive to avert bankruptcy and its impact on the members of the board of directors, as well as the newly enacted type of liability, based on a judicial decision. This part deals with questions such as, what extent can be expected in this type of liability, how will accessorial guarantor relationship or what...