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Temporality and Rhythmic Structure in Thirteen Drums by Maki Ishii and Rebond a by Iannis XenakisLiu, Yi-Jan 08 1900 (has links)
This dissertation will focus on the concepts of musical time of two solo multiple-percussion compositions, Thirteen Drums (1985) by Maki Ishii and Rebond A (1987-1989) by Iannis Xenakis. The aesthetic experience of musical works is tied to the perception of musical time. Performers have to understand the concepts and methods of construction of musical time in order to interpreting composer’s works. The model of cognitive process in neuroscience of music and the information processing theory from cognitive psychology is provided to explain the perception of musical time and its importance to the aesthetic experience of music. The rhythmic structure, which is essential in temporal structure to the perception of musical time, is examined in depth to show its significant influence on the aesthetic experience in both works. Rhythmic tension will also affect the aesthetic experience.
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Neuronal Deep Fakes Data Driven Optimization of Reduced Neuronal ModelJanuary 2020 (has links)
abstract: Neuron models that behave like their biological counterparts are essential for computational neuroscience.Reduced neuron models, which abstract away biological mechanisms in the interest of speed and interpretability, have received much attention due to their utility in large scale simulations of the brain, but little care has been taken to ensure that these models exhibit behaviors that closely resemble real neurons.
In order to improve the verisimilitude of these reduced neuron models, I developed an optimizer that uses genetic algorithms to align model behaviors with those observed in experiments.
I verified that this optimizer was able to recover model parameters given only observed physiological data; however, I also found that reduced models nonetheless had limited ability to reproduce all observed behaviors, and that this varied by cell type and desired behavior.
These challenges can partly be surmounted by carefully designing the set of physiological features that guide the optimization. In summary, we found evidence that reduced neuron model optimization had the potential to produce reduced neuron models for only a limited range of neuron types. / Dissertation/Thesis / Doctoral Dissertation Neuroscience 2020
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Smoking and Cerebrovascular Disease: A Three-phase Research ProgramEdjoc, Rojiemiahd January 2013 (has links)
Purpose: The purpose of this research program was three-fold. First it aimed to determine the effectiveness of smoking cessation interventions in increasing cessation rates in smokers with cerebrovascular disease and whether smoking cessation reduces stroke recurrence. Second it aimed to determine the prognostic influence of smoking and its association with stroke severity, disability, length of stay in hospital and mortality. Third it aimed to identify multi-level correlates of smoking cessation in Canadians who reported stroke symptoms in a large population based survey.
Methods: Two systematic reviews and meta-analyses were performed to achieve the first objective. For the second objective, a retrospective cohort study was undertaken using variables from the Registry of the Canadian Stroke Network. Finally, the third objective was achieved by analyzing respondents from the Canadian Community Health Survey.
Results: There is a paucity of intervention studies examining the effectiveness of smoking cessation in smokers with cerebrovascular disease. Most intervention studies that were found, failed to employ evidence-based approaches to smoking cessation. No evidence was found in regards to the effect of smoking cessation on stroke recurrence. We found smokers had strokes at a younger age compared to non-smokers. We found that in transient ischemic attacks and intracerbral haemorrhage, smoking was a significant predictor of stroke severity, disability, length of stay in hospital and 1 year mortality. Correlates of smoking cessation among Canadians who have experienced symptoms of a stroke included: higher education and income, implementation of household and vehicle smoking restrictions, access to a general practitioner and the use of smoking cessation pharmacotherapies and counselling support. Co-morbidities such as depression and alcohol consumption reduced the likelihood of successful cessation.
Conclusions: This three-phase research program elucidated the gaps in intervention research for this population along with co-morbidities that hinder success in cessation. Smoking negatively impacted outcomes such as disability, hospital length of stay and mortality in patients with transient ischemic attacks and intracerebral haemorrhage strokes. Future interventions should take into account modifiable smoking cessation correlates in order to increase cessation rates in smokers with cerebrovascular disease.
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Multi-family housing complex: The effectiveness of using community development block grant funds and other financial sources to address residential housing demand in Terrebonne Parish, LouisianaJanuary 2013 (has links)
The following research will respond to an active request for proposals to develop workforce housing in Terrebonne Parish, Louisiana to create one (1) multi-family rental housing development that services residents earning less than 80% of the Area Median Income. The proposed research will explore the feasibility of development in Terrebonne as well as determining financial structure, including tax incentives that would best utilize a $5.7 million dollar community development block grant funds allocated from hurricanes Ike and Gustav. The project is intended to be energy efficient, aesthetically pleasing and use universal design standards that aim at making the resulting multi-family community comparable and competitive with recently developed market rate apartments. / 0 / SPK / specialcollections@tulane.edu
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Multi-Threshold Bidirectional MEMS Inertial SwitchesNiyazi, Alhammam 11 1900 (has links)
In this work, MEMS inertial switches intended to be triggered at multiple acceleration thresholds in two directions were implemented and proven effective. The switches consume virtually no power in their open switching state. Multiple acceleration thresholds can be beneficial in triggering different actions for different acceleration events. Low power consumption can aid in their use for portable applications such as in cycling helmets.
The developed designs rely mainly on a suspended shuttle mass, which is used to implement one of two methods of actuation. The first relies on simple contact between the moving shuttle mass and a flexible electrode. In the second, the pull-in instability is induced by applying a voltage between a cantilever and an electrode, and then having the shuttle mass force the cantilever moving towards the electrode as it moves under the applied acceleration. Ten designs varying in their actuation method, suspension design, intended acceleration thresholds, and dimensions were modeled using a finite element model, fabricated, through the SOIMUMPs process, and then electrically and mechanically tested. Mechanical testing has been conducted using Drop-table tests and mechanical shakers.
The simple contact devices were proven effective through shock test results showing triggering at two acceleration thresholds in two directions. Initial results also were promising for the pull-in based devices showing switching by moving their shuttle mass with a probe while applying appropriate voltage and observing under a microscope.
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Engineering Nature-Inspired Heuristics for the Open Shortest Path First Weight Setting ProblemMohiuddin, Mohammed Aijaz 04 1900 (has links)
In the thesis of “Mohammed Aijaz Mohiuddin”, Engineering Nature-Inspired Heuristics for the Open Shortest Path First Weight Setting Problem, nature inspired heuristics were developed. Besides the existing two objectives, namely maximum utilization and the number of congested links, a third objective namely the number of unused links was used to formulate the fuzzy based objective function for the OSPFWS problem. The idea was to make use unused network links if any. Furthermore, a hybrid fuzzy based evolutionary Particle Swarm Optimization (FEPSO) algorithm was designed that harnessed evolutionary intelligence along with swarm intelligence. The proposed FEPSO algorithm was tested on different size test cases and its performance was mutually compared with other algorithms namely Simulated Annealing, Simulated Evolution, Particle Swarm Optimization, Weighted Aggregation Particle Swarm Optimization, Pareto-dominance Particle Swarm Optimization and Non-dominating Sorting Genetic Algorithm. Obtained results suggested the better performance of FEPSO among other algorithms over majority of test cases. / Thesis (PHD)--University of Pretoria, 2018. / Computer Science / PhD / Unrestricted
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Partial preference models in discrete multi-objective optimization / Intégration de préférences expertes en optimisation multicritèreKaddani, Sami 10 March 2017 (has links)
Les problèmes d’optimisation multi-objectifs mènent souvent à considérer des ensembles de points non-dominés très grands à mesure que la taille et le nombre d’objectifs du problème augmentent. Générer l’ensemble de ces points demande des temps de calculs prohibitifs. De plus, la plupart des solutions correspondantes ne sont pas pertinentes pour un décideur. Une autre approche consiste à utiliser des informations de préférence, ce qui produit un nombre très limité de solutions avec des temps de calcul réduits. Cela nécessite la plupart du temps une élicitation précise de paramètres. Cette étape est souvent difficile pour un décideur et peut amener à délaisser certaines solutions intéressantes. Une approche intermédiaire consiste à raisonner avec des relations de préférences construites à partir d’informations partielles. Nous présentons dans cette thèse plusieurs modèles de relations partielles de préférences. En particulier, nous nous sommes intéressés à la génération de l’ensemble des points non-dominés selon ces relations. Les expérimentations démontrent la pertinence de notre approche en termes de temps de calcul et qualité des points générés. / Multi-objective optimization problems often lead to large nondominated sets, as the size of the problem or the number of objectives increases. Generating the whole nondominated set requires significant computation time, while most of the corresponding solutions are irrelevant to the decision maker. Another approach consists in obtaining preference information, which reduces the computation time and produces one or a very limited number of solutions. This requires the elicitation of precise preference parameters most of the time, which is often difficult and partly arbitrary, and might discard solutions of interest. An intermediate approach consists in using partial preference models.In this thesis, we present several partial preference models. We especially focused on the generation of the nondominated set according to these preference relations. This approach shows competitive performances both on computation time and quality of the generated preferred sets.
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Cooperation in self-organized heterogeneous swarmsMoritz, Ruby Louisa Viktoria 26 February 2015 (has links)
Cooperation in self-organized heterogeneous swarms is a phenomenon from nature with many applications in autonomous robots. I specifically analyzed the problem of auto-regulated team formation in multi-agent systems and several strategies to learn socially how to make multi-objective decisions. To this end I proposed new multi-objective ranking relations and analyzed their properties theoretically and within multi-objective metaheuristics. The results showed that simple decision mechanism suffice to build effective teams of heterogeneous agents and that diversity in groups is not a problem but can increase the efficiency of multi-agent systems.
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Modelling and Pitch Control of a Re-Configurable Unmanned AirshipTuta Navajas, Gilmar 14 April 2021 (has links)
Lighter than air (LTA) vehicles have many advantageous capabilities over other aircraft, including low power consumption, high payload capacity, and long endurance. However, they exhibit manoeuvrability and control reliability challenges, and these limitations are particularly significant for smaller unmanned LTA. In this thesis, a 4 m length autonomous airship with a sliding gondola is presented. A rigid keel, mounted to the helium envelope, follows the helium envelope profile from the midsection to the nose of the vehicle. Moving the gondola along the keel produces upwards of 90-degree changes in pitch angle, thereby improving manoeuvrability and allowing for rapid changes in altitude. The longitudinal multi-body equations of motion were developed for this prototype using the Boltzmann–Hamel method. An adaptive PID controller was then designed to control the pitch inclination using the gondola’s position. This control system is capable of self-tuning the controller gains in real time by minimizing a pre-defined sliding condition. Experimental flight tests were carried out to evaluate the controller’s performance on the prototype.
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Safe navigation and path planning for multiagent systems with control barrier functionsSchoer, Andrew 22 January 2021 (has links)
Finding safe trajectories for multiagent autonomous systems can be difficult, especially as multiple robots and obstacles are added to the system. Control barrier functions (CBFs) have been effective in addressing this problem. Although the use of CBFs for guaranteeing safe operation is well established, there is no standard software implementation to simplify the integration of these techniques into robotic systems. We present a CBF Toolbox to fill this void.
Although the CBF Toolbox can be used to ensure safety based on local control decisions, it may not be sufficient to guide a robots to their goals in certain environments. In these cases, path planning algorithms are required. We present one such algorithm, which is the multiagent extension of the CBF guided rapidly-exploring random trees (CBF-RRT) to demonstrate how the CBF Toolbox can be applied.
This work addresses the theory behind the CBF Toolbox, as well as presenting examples of how it is applied to multiagent systems. Examples are shown for its use in both simulation and hardware experiments. Details are provided on CBF guided rapidly-exploring random trees (CBF-RRT), and its application to multiagent systems with multiagent CBF-RRT (MA-CBF-RRT) that streamlines safe path planning for teams of robots.
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