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Recent technological developments have implemented the use of proportional control in prosthetic hands, giving rise to the importance of appropriate myoelectric control. EMG models in the past have assumed a linear proportionality to simplify the EMG-force relationships. However, it has been shown that a non-linear EMG-force relationship may be a more effective model. This study focused on evaluating three different control algorithms for a novel myoelectric training device, consisting of a toy car controlled by EMG signals from the distal muscles in the arm. Sixteen healthy adult subjects (5 male and 11 female) with an average age of 23.6 years (SD = 2.7) were asked to drive the car through a slalom course. Completion times as well as number of errors (wall hits, cone hits, and reversals) were recorded to evaluate performance. The NASA TLX was administered to evaluate psychometrics such as mental demand, physical demand, frustration, and overall workload. The average total errors per trial on the final day of testing using the linear proportional algorithm was found to be statistically significantly (p < 0.05) lower than digital and non-linear proportional. The average course completion time per trial and overall workload using the non-linear proportional algorithm was found to be statistically significantly (p < 0.05) lower than digital and linear proportional. These results suggest that a non-linear algorithm would be most appropriate for myoelectric control in prosthetic hands.

The Cox proportional hazards model is a standard tool for modelling the effect of covariates on time to event in the presence of censoring. The appropriateness of this model is conditioned by the validity of the proportional hazards assumption. The assumption is explained in the thesis and methods for its testing are described in detail. The tests are implemented in R, including self-written version of the Lin- Zhang-Davidian test. Their application is illustrated on medical data. The ability of the tests to reveal the violation of the proportional hazards assumption is investigated in a simulation study. The results suggest that the highest power is attained by the newly implemented Lin-Zhang-Davidian test in most cases. In contrast, the weighted version of the Lin-Wei-Ying test was found to have inadequate size for low sample sizes.

Escalonamento com controle de overdose (EWOC-PH, escalation with overdose control proporcional hazards) é um método bayesiano com controle de overdose que estima a dose máxima tolerada (MTD, maximum tolerated dose) assumindo que o tempo que um paciente leva para apresentar toxicidade segue o modelo de riscos proporcionais. Neste trabalho analisamos quais são as consequências em adotarmos um método que se baseia no modelo de riscos proporcionais quando o tempo até toxicidade segue o modelo de chances de sobrevivência proporcionais. A fim de buscar responder se teríamos uma superestimativa ou uma subestimativa da MTD foram feitas simulações em que consideramos dados de chances de sobrevivência proporcionais e aplicação do método EWOC-PH para analisarmos a MTD. Como uma extensão do método EWOC-PH, propomos o método EWOC-POS que assume que os tempos seguem o modelo de chances de sobrevivência proporcionais. / Escalation with overdose control proportional hazards is a Bayesian method with overdose control that estimates the maximum tolerated dose (MTD) assuming that the time a patient takes to show toxicity follows the proportional hazards model. In this work, we analyse the consequences of adopting a method based on the proportional hazard model when the time until toxicity follows the proportional survival model. In order to seek to answer if we would have an overestimate or an underestimate of MTD, simulations were performed in which we considered proportional odds survival data and application of the EWOC-PH method. As an extension of the EWOC-PH method, we propose the EWOC-POS method which assumes that time until toxicity follows the proportional odds survival model.

Avec l’émergence rapide des applications Internet, il est prévu que le trafic mobile mondial augmente de huit fois entre fin 2018 et 2022. En même temps, les futurs systèmes de communication se devront aussi d’améliorer l'efficacité spectrale des transmissions, le temps de latence et l’équité entre utilisateurs. À cette fin, une technique d’accès multiple non orthogonal (NOMA) a été récemment proposée comme un candidat prometteur pour les futurs accès radio. La technique NOMA est basée sur un nouveau domaine de multiplexage, le domaine des puissances. Elle permet la cohabitation de deux ou plusieurs utilisateurs par sous-porteuse ou sous-bande de fréquence. Cette thèse aborde plusieurs problèmes liés à l’allocation de ressources basée sur NOMA afin d'améliorer les performances du réseau en termes d'efficacité spectrale, de débit et/ou d’équité entre utilisateurs. Dans ce sens, des solutions théoriques et algorithmiques sont proposées et des résultats numériques sont obtenus afin de valider les solutions et de vérifier la capacité des algorithmes proposés à atteindre des performances optimales ou sous-optimales. Après une étude bibliographique des différentes techniques d’allocation de ressources présentée dans le premier chapitre, on propose dans le deuxième chapitre plusieurs stratégies d’allocation de ressource où une réduction de la bande utilisée par les utilisateurs est ciblée. Les résultats de simulation montrent que les stratégies proposées améliorent à la fois l’efficacité spectrale et le débit total des utilisateurs par rapport aux systèmes basés uniquement sur des techniques d’accès orthogonales. Quant au troisième chapitre, il étudie la performance du Proportional Fairness (PF) Scheduler tout en considérant que la bande passante est disponible en totalité. Dans ce sens, plusieurs améliorations basées sur le PF sont proposées, qui offrent au système NOMA des avantages en termes de débit, d’équité entre utilisateurs et de qualité de service. Dans le quatrième chapitre, nous proposons plusieurs techniques d’allocation de ressources qui donnent aux utilisateurs la possibilité de favoriser le débit par rapport à l’équité entre utilisateurs et vice versa. Dans le dernier chapitre, différentes techniques permettant une transmission hybride broadcast/broadband sur la même bande de fréquence sont proposées et comparées à l’état de l’art. / With the proliferation of Internet applications, between the end of 2016 and 2022, total mobile traffic is expected to increase by 8 times. At the same time, communications networks are required to further enhance system efficiency, latency, and user fairness. To this end, non-orthogonal multiple access (NOMA) has recently emerged as a promising candidate for future radio access. By exploiting an additional multiplexing domain, the power domain, NOMA allows the cohabitation of two or more users per subcarrier, based on the principle of signal superposition. This dissertation addresses several radio resource allocation problems in mobile communication systems, in order to improve network performance in terms of spectral efficiency, through put, or fairness. Theoretical analysis and algorithmic solutions are derived. Numerical results are obtained to validate our theoretical findings and demonstrate the algorithms ability of attaining optimal or sub-optimal solutions. To this direction, the second chapter of this thesis investigates several new strategies for the allocation of radio resources (bandwidth and transmission power) using NOMA principle, where the minimization of the total amount of used bandwidth is targeted. Extensive simulation results show that the proposed strategies for resource allocation can improve both the spectral efficiency and the cell-edge user throughput, especially when compared to schemes employing only orthogonal signaling. A context where the total bandwidth is available has also been studied, in the 3rd chapter where we investigate the performance of the proportional fairness (PF) scheduler, and we propose modifications to it, at the level of user scheduling and power allocation that show to improve the system capacity, user fairness and QoS. In the 4th chapter, we proposed new pairing metrics that allow to favor the fairness at the expense of the throughput and vice versa. The proposed metrics show enhancements at the level of system capacity, user fairness, and computational complexity. Different techniques that allow a hybrid broadcast/multicast transmission on the same frequency platform are proposed in the last chapter and compared to the state of the art.

The two and k-sample tests of equality of the survival distributions against the alternatives including cross-effects of survival functions, proportional and monotone hazard ratios, are given for the right censored data. The asymptotic power against approaching alternatives is investigated. The tests are applied to the well known chemio and radio therapy data of the Gastrointestinal Tumor Study Group. The P-values for both proposed tests are much smaller then in the case of other known tests. Differently from the test of Stablein and Koutrouvelis the new tests can be applied not only for singly but also to randomly censored data.

Counting efficiencies were determined by empirical measurement and Monte Carlo simulation for carbon-14, strontium-89, strontium-90, and yttrium-90 standards counted by low-background gas flow proportional counter for strontium carbonate precipitates in the range from 3 to 33 mg cm⁻². The maximum beta particle energies range from 0.156 MeV for carbon-14 to 2.28 MeV for yttrium-90. The parameters for estimating the counting efficiency are summarized for sources with areal thickness of 14 mg cm⁻² and over the range in strontium carbonate areal thickness from 0.1 mg cm⁻² to 33 mg cm⁻². Uncertainty budgets providing estimates of the uncertainty, sources of variability in the calibration process, and the total expanded uncertainty are presented. Information is presented for the Monte Carlo simulation regarding the composition of the detector window, the energy excluded by the amplifier discriminator of the counting system, and the physical density of materials for this analytical process. The histogram normalization routine implemented within MCNP is described and found to bias the probability distribution for beta-particle energy spectra. The difference in the specification of the probability distribution for beta-particle energy spectra in ICRU 56 Appendix D and MCNP requirements are described and a correction for the bias introduced during the normalization process for beta spectra is provided. Counting efficiencies determined by empirical measurement and Monte Carlo simulations agree within the total expanded uncertainties of the measurements and the uncertainties of the Monte Carlo simulations.

The thesis examines the reasons why the German National Assembly of 1919 chose proportional representation to elect officials to the German Reichstag. Sources include the series Quellen zur Geschichte des Parlamentarismus and die politische Parteien, the "Hajo Holborn Papers", and the Reich Ministry of Interior debates concerning the institutional draft. The thesis traces the arguments for proportional representation, its use throughout Europe before 1914, and voting reform in Germany during World War I. The thesis surveys the German provisional government's adoption of proportional representation, emphasizing the constitutional drafts of Hugo Preuss and the role of the provisional government. Finally, the thesis scrutinizes the National Assembly debates, concluding that most of its members had already decided to follow the provisional government's course and accept proportional representation.

Forskning om de särskilda matematikkunskaper som lärare behöver för att undervisa om proportionella samband är begränsad. Därav är syftet med denna studie att bidra med insikter om pedagogiska ämneskunskaper inom proportionella samband. Det görs med utgångspunkt i två frågeställningar, som utgår från två kategorier av pedagogiska ämneskunskaper i matematik som Ball et al. (2008) beskrivit: (1) Vilka kunskaper om proportionalitet och elever visar lärare? (2) Vilka kunskaper om proportionalitet och undervisning visar lärare? Studien har genomförts med hjälp av kvalitativa semistrukturerade intervjuer med fyra lärare som arbetar i grundskolan och undervisar i matematik. Resultatet visar på flera exempel på vad som är kunskap inom de båda kategorierna. Bland annat beskrivs olika representationsformer och hur de kan användas för progression av undervisning som exempel på kunskaper om proportionalitet och undervisning. Sådana kunskaper är av stor betydelse att lärare besitter eftersom förståelse för proportionella samband framhålls som viktigt inom flera områden i matematiken. / Research about the special kind of mathematical knowledge that teachers need to teach proportional relationships is limited. Therefore, the aim of this study is to contribute with insights into pedagogical content knowledge about proportionality. To study this, two questions were posed: (1) What can knowledge of proportionality and students be? (2) What can knowledge of proportionality and teaching be? The two questions are based on two different categories of pedagogical content knowledge in mathematics that Ball et al. (2008) have described. This study has been conducted through qualitative semi-structured interviews with four teachers who work with students in the ages of 10-13 and teaches mathematics.  The result of the study shows several examples of pedagogical content knowledge in both categories that has been studied. For example, different representations and how they can be used to progress the teaching are described as examples of knowledge of proportionality and teaching. It is of great importance that teachers possess such knowledge considering understanding of proportional relationships has been described as a key to many areas of mathematics.