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On Projective Planes & Rational IdentitiesBrunson, Jason Cornelius 24 May 2005 (has links)
One of the marvelous phenomena of coordinate geometry is the equivalence of Desargues' Theorem to the presence of an underlying division ring in a projective plane. Supplementing this correspondence is the general theory of intersection theorems, which, restricted to desarguian projective planes P, corresponds precisely to the theory of integral rational identities, restricted to division rings D. The first chapter of this paper introduces projective planes, develops the concept of an intersection theorem, and expounds upon the Theorem of Desargues; the discussion culminates with a proof of the desarguian phenomenon in the second chapter. The third chapter characterizes the automorphisms of P and introduces the theory of polynomial identities; the fourth chapter expands this discussion to rational identities and cements the ``dictionary''. The last section describes a measure of complexity for these intersection theorems, and the paper concludes with a curious spawn of the correspondence. / Master of Science
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Designing is Cooking: A Museum of GastronomyLam, Alwan Abdulrahman 30 May 2012 (has links)
Those who eat share a relationship with design. The Museum of Gastronomy, a museum located at the Washington D.C. National Mall, would dedicate a space to a full-sense experience pursuing a relationship between food, culture, and design. The National Mall is a symbolic setting dedicated to U.S. heritage via museums, memorials, and the honoring of legacies accessible to the public. As the U.S. is a melting pot of different nationalities, this museum would fill an open niche devoted to celebrating the cultural heritage of cooking throughout the cycle of food consumption.
As consumers, regardless of notice or intention, we have an intimate relationship with food as means of survival. Cooking, the method for preparing this vital element, is also an expression of culture, style, and use of available resources. In essence, cooking is an everyday design: a crucial aspect of our very survival.
Therefore:
food → cooking → design → survival → food → cooking
Similarly, it is the architect's mission to reach an effective design with available "ingredients," forces, or kit-of-parts within a project. In the Museum of Gastronomy, the architect would become the unifying source between a relationship literally built between food, people, and design in an interactive experience. This would result in a space dedicated to showcasing and combining the concept of "cooking is designing."
Incorporating these components into a museum located at the National Mall would personify an experience of the cooking processes as a building block of every-day observation of design. / Master of Architecture
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Intersection Safety Analysis Methodology for Utah RoadwaysGibbons, Joshua Daniel 01 May 2018 (has links)
Roadway safety continues to be a priority for the Utah Department of Transportation (UDOT) Traffic and Safety Division. UDOT has participated in and managed several research projects in recent years to determine the roadway segments of highest safety concern in the state. This research has provided UDOT with more tools to assist in safety project prioritization. Researchers in Department of Civil and Environmental Engineering at Brigham Young University (BYU) have worked with UDOT and the Statistics Department at BYU to create two network screening statistical tools called the Utah Crash Prediction Model (UCPM) and the Utah Crash Severity Model (UCSM) to analyze roadway segment safety. The Roadway Safety Analysis Methodology (RSAM) was developed as a process to run these segment models. Because a significant portion of crashes occur at intersections, there is a need to analyze roadway safety specifically at intersections. This research focuses on the development of the Utah Intersection Crash Prediction Model (UICPM) and the Intersection Safety Analysis Methodology (ISAM). The UICPM is a Bayesian generalized linear model that determines crash distributions for each intersection based on roadway characteristics and historical crash data. The observed number of crashes at each intersection is compared with the crash distribution, and a percentile value is calculated as the probability that the number of crashes occurring at an intersection in a particular year is less than or equal to the average annual number of crashes. A high percentile value indicates that more crashes were observed than expected and the intersection is a hot spot and should be considered for safety improvements. All intersections are ranked at the state, UDOT Region, and county levels based on the percentile value, the higher ranks having higher percentile values. The ISAM is the three-step process that was developed to execute the UICPM. The first step is to prepare the model input by formatting and combining the roadway characteristics and crash data files. Crashes are assigned to intersections if they fall with the functional area of an intersection. Due to data limitations, the ISAM is currently being used only for intersections of at least two state routes. It is anticipated that, as more data are made available, the ISAM will function properly for intersections of non-state routes as well. The second step is to execute the UICPM using the R GUI tool and R software. The third step is to create a two-page Intersection Safety Analysis Report (ISAR) for intersections of interest and maps of the state, UDOT Regions, and counties with the model results. Parts of the ISARs are auto-generated and the rest is entered manually by an analyst. The two-page ISARs will be used by UDOT Regions to prioritize intersection safety projects in their respective areas.
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ESTIMATION OF PEDESTRIAN SAFETY AT INTERSECTIONS USING SIMULATION AND SURROGATE SAFETY MEASURESAgarwal, Nithin K. 01 January 2011 (has links)
With the number of vehicles increasing in the system every day, many statewide policies across the United States aim to increase the use of non- motorized transportation modes. This could have safety implications because the interaction between motorists and non-motorists could increase and potentially increasing pedestrian-vehicle crashes. Few models that predict the number of pedestrian crashes are not sensitive to site-specific conditions or intersection designs that may influence pedestrian crashes. Moreover, traditional statistical modeling techniques rely extensively on the sparsely available pedestrian crash database.
This study focused on overcoming these limitations by developing models that quantify potential interactions between pedestrians and vehicles at various intersection designs using as surrogate safety measure the time to conflict. Several variables that capture volumes, intersection geometry, and operational performance were evaluated for developing pedestrian-vehicle conflict models for different intersection designs. Linear regression models were found to be best fit and potential conflict models were developed for signalized, unsignalized and roundabout intersections. Volume transformations were applied to signalized and unsignalized conditions to develop statistical models for unconventional intersections.
The pedestrian-vehicle conflicting volumes, the number of lanes that pedestrians are exposed to vehicles, the percentage of turning vehicles, and the intersection conflict location (major or minor approach) were found to be significant predictors for estimating pedestrian safety at signalized and unsignalized intersections. For roundabouts, the pedestrian-vehicle conflicting volumes, the number of lanes that pedestrians have to cross, and the intersection conflict location (major or minor approach) were found to be significant predictors. Signalized intersection models were used for bowtie and median U-turn intersections using appropriate volume transformations. The combination of signalized intersection models for the intersection area and two-way unsignalized intersection models for the ramp area of the jughandle intersections were utilized with appropriate volume transformations. These models can be used to compare alternative intersection designs and provide designers and planners with a surrogate measure of pedestrian safety level for each intersection design examined.
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Study of photo induce process by quantum chemistry and quantum dynamics methods / Etude de processus photochimique par une approche couplant chimie quantique et dynamique quantiquePerveaux, Aurelie 08 December 2015 (has links)
C’est dernières années, les progrès des techniques expérimentales combinées avec les simulations théoriques ont données un accès à l’étude et le contrôle des réactions photochimiques dans des systèmes moléculaires de grande taille. Ceci ouvre des portes à de nouvelles applications technologiques. Par exemple, les molécules de la famille du 3-hydroxychromone et de l’aminobenzonitrile sont des types de systèmes où les spectres de fluorescences vont présentés des différences importantes suivant l’environnement du système ou même suivant les substituants utilisés. Ce type de propriété est crucial dans le domaine des matériaux organique, afin de pouvoir comprendre et designer des matériaux qui présentent des propriétés optiques choisis tells que les marqueurs fluorescents dans le domaine médical par exemple.Notre stratégie pour étudier la réactivité photochimique est la suivante: *Explorer la surface d’énergie potentielle et optimiser les points spécifiques avec des calculs de chimie quantiques. Dans un premier temps, on a utilisé des méthodes CASSCF/CASPT2 et la méthode PCM pour décrire les effets de solvant. * Génération des surfaces d énergies potentielles exprimer sous la forme de fonctions analytiques des coordonnées nucléaires. * Résolution de l’équation de Schrödinger dépendant du temps pour les noyaux et pour tout les derges de libertés de la molécule. Cette étape est faite à l’aide de la méthode multilayer multiconfiguration time-dependent hartree (ML-MCTDH). / Over the last decades, progress in experimental techniques combined with theoretical simulations has given access to studying and controlling the photochemical reactivity of large molecular systems with numerous technological applications. 3-hydroxychromone and aminobenzonitrile-like molecules are an example where different fluorescence patterns are observed, depending of the solvent or its substituents. Such properties are crucial in the field of organic materials to understand and design materials with specific optical properties such as fluorescent markers.Our strategy to study the photochemistry reactivity is summarised as follows: * Exploring the potential energy surfaces and optimising specific points with quantum chemistry calculations. In a first stage, these are run at the CASSCF/CASPT2 level of theory with a polarised extended basis set, and the solvent effect is described implicitly with the PCM model. * Generating the full dimension potential energy surfaces as analytical functions of the nuclear coordinates.* Solving the nuclear time-dependent Schrödinger equation for all the degrees of freedom. This is achieved with the multilayer Multi-Configuration Time-Dependent Hartree method (ML-MCTDH).
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Quantitative Analyse der Komplexität von Knotenpunkten und ihr Einfluss auf die UnfallhäufigkeitGidion, Fritjof 27 September 2019 (has links)
Innerorts-Knotenpunkten gilt aufgrund der vielen Unfälle eine hohe Aufmerksamkeit in der Unfallforschung und -prävention. Die vorliegende Arbeit identifiziert und quantifiziert Einflüsse, welche die Komplexität von Knotenpunkten bestimmen und sich so auf Fehlerraten und somit Unfallzahlen auswirken. Dazu werden verallgemeinert lineare Modelle verwendet. Dabei erweisen sich neben der Verkehrsstärke vor allem die Anzahl der Konfliktpunkte an nichtsignalisierten Knotenpunkten sowie die Links- und Rechtsabbiegersignalisierungen an signalisierten Knotenpunkten als signifikante Einflüsse auf die Unfallzahlen. Entsprechend können komplexitätsverringernde Maßnahmen abgeleitet werden. / A great deal of research on road safety and accident prevention focuses on urban intersections due to high crash frequencies. In this paper urban intersection complexity is broken down into single quantifiable effects that determine crash counts using generalised linear models. Besides traffic volumes it can be shown that the number of conflict points explain crash counts at non-signalised intersections. Whereas crash counts at signalised intersections are effected by protected left- and right-turn signalling. Practical measures can be deduced from this work in order to manage intersection safety.
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Simulation of the Impact of Connected and Automated Vehicles at a Signalized IntersectionAlmobayedh, Hamad Bader 30 May 2019 (has links)
No description available.
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HAMMS : Managing a mix of human driven and autonomous vehicles in four-way intersections / HAMMS : Korsningshantering förblandningen av mänskligt och autonomtframförda fordonLjungberg, Sebastian, Schalling, Fredrik January 2017 (has links)
The purpose of this report is to improve the flow of trafficin intersections through the use of a dynamic algorithm.People spend on average more than six weeks commuting towork in Stockholm every year. A large part of the time thatis spent in traffic is due to the time delay in intersections.In this report, sensors that measure speed and distanceto the vehicle are used instead of detectors that only knowif a car is there or not. There are existing solutions that canoptimise the flow for autonomous cars but since the trafficmay consist of a mix of autonomous and human drivenvehicles during the upcoming 40 years those solutions arenot usable for some time.In this work, a system that can handle both autonomousand human driven vehicles is created. The limitation of thesystem is that it can only receive two cars coming from differentdirections simultaneously. The system does not workfor car queues. The system measures the speed of- and thedistance to the vehicles continuously.According to the simulations that were made the algorithmthat has been designed through this project is moretime efficient than the system that is in place today, assumingthat the assumptions that were made for the currentsystem are correct.The conclusion in this report is that it is possible tomake a system that is more time efficient than the one thatis in use today. / Syftet med den här rapporten är att förbättra flödet ikorsningar genom en dynamisk algoritm. Människor sitterdrygt 6 veckor i bilköer varje år. En stor del av av denspenderande tiden i traffiken är på grund av att fordonbehöver stanna i korsningar.I den här rapporten har sensorer som mäter hastighetoch distans använts istället för dagens detektorer som endastkänner av om ett fordon kör över detektorn eller inte.Det finns andra rapporter med lösningar för att öka flödeti korsningar för självkörande bilar men om man kollar pådet kommande 40 åren kommer det troligtsvis att vara enblandning av självkörande och mänskligt körda bilar.I det här arbetet skapas ett system som kan interageramed både mänskligt körda och autonoma bilar. Begränsningarnai det här systemet är att systemet endast kan taemot två bilar som kommer från olika ingångar i korsningensamtidigt. Systemet fungerar inte för bilköer. Systemet mäterden nuvarande hastigheten och distansen på fordonen.Systemet fungerar för alla olika kombinationer av mänskligtoch självkörande bilar.Resultatet av den här rapporten är att en algoritm harutvecklats och är mer tidseffektivt än systemet som användsi Sverige idag, med våra antaganden om systemet som harutveklats i den här rapporten och systemet som användsidag. Resultatet är baserat på korsningar där bara två bilarmöts utan köer.Slutsatsen av den här rapporten är att det är möjligtatt göra ett system som är mer tidseffektivt än systemetvi använder oss av idag, men vi kan inte säkertsätlla attsystemet i den här rapporten är mer robus och driftsäkertän det som används i Sverige idag.
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Safety, Operational, and Energy Impacts of In-Vehicle Adaptive Stop Displays Using Connected Vehicle TechnologyNoble, Alexandria M. 23 January 2015 (has links)
Driving through an un-signalized intersection creates multiple opportunities for missed or misunderstood information. Stop signs, in particular, can be stolen, covered by vegetation, or rotated out of place, leading to an absence of information, contributing to inappropriate decision-making and crashes. Stop controlled intersections have also been shown to be a source of unnecessary delay and emissions due to their frequent, often inappropriate use. Using connected vehicle technology, it is possible to place an electronic stop sign within the vehicle that tells the driver to stop when a conflict in the intersection is imminent, thus reducing the probability of missed information by the driver, and decreasing the amount of unnecessary delay, fuel consumption, and emissions. Before implementing any new technology, it is important to assess it from both a transportation engineering and human factors standpoint to assess the value of the system.
The objective of this study was to assess several key benefits of an adaptive in-vehicle stop display as well as to determine if there are any negative safety implications with the use of this system. This assessment was accomplished through a test track experiment where participants experienced conditions where a standard R1-1 stop sign was displayed on the in-vehicle display, as well as an experimental sign, which informed them to proceed through the intersection with caution. Data collected from in-vehicle sensors was analyzed, and results indicate that the implementation of this technology reduces delay, decreases fuel consumption, and does not instigate any safety decrements. / Master of Science
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Opérateurs de typage non-idempotents, au delà du lambda-calcul / Non-idempotent typing operators, beyond the lambda-calculusVial, Pierre 07 December 2017 (has links)
L'objet de cette thèse est l'extension des méthodes de la théorie des types intersections non-idempotents, introduite par Gardner et de Carvalho, à des cadres dépassant le lambda-calcul stricto sensu.- Nous proposons d'abord une caractérisation de la normalisation de tête et de la normalisation forte du lambda-mu calcul (déduction naturelle classique) en introduisant des types unions non-idempotents. Comme dans le cas intuitionniste, la non-idempotence nous permet d'extraire du typage des informations quantitatives ainsi que des preuves de terminaison beaucoup plus élémentaires que dans le cas idempotent. Ces résultats nous conduisent à définir une variante à petits pas du lambda-mu-calcul, dans lequel la normalisation forte est aussi caractérisée avec des méthodes quantitatives. - Dans un deuxième temps, nous étendons la caractérisation de la normalisation faible dans le lambda-calcul pur à un lambda-calcul infinitaire étroitement lié aux arbres de Böhm et dû à Klop et al. Ceci donne une réponse positive à une question connue comme le problème de Klop. À cette fin, il est nécessaire d'introduire conjointement un système (système S) de types infinis utilisant une intersection que nous qualifions de séquentielle, et un critère de validité servant à se débarrasser des preuves dégénérées auxquelles les grammaires coinductives de types donnent naissance. Ceci nous permet aussi de donner une solution au problème n°20 de TLCA (caractérisation par les types des permutations héréditaires). Il est à noter que ces deux problèmes n'ont pas de solution dans le cas fini (Tatsuta, 2007).- Enfin, nous étudions le pouvoir expressif des grammaires coinductives de types, en dehors de tout critère de validité. Nous devons encore recourir au système S et nous montrons que tout terme est typable de façon non triviale avec des types infinis et que l'on peut extraire de ces typages des informations sémantiques comme l'ordre (arité) de n'importe quel lambda-terme. Ceci nous amène à introduire une méthode permettant de typer des termes totalement non-productifs, dits termes muets, inspirée de la logique du premier ordre. Ce résultat prouve que, dans l'extension coinductive du modèle relationnel, tout terme a une interprétation non vide. En utilisant une méthode similaire, nous montrons aussi que le système S collapse surjectivement sur l'ensemble des points de ce modèle. / In this dissertation, we extend the methods of non-idempotent intersection type theory, pioneered by Gardner and de Carvalho, to some calculi beyond the lambda-calculus.- We first present a characterization of head and strong normalization in the lambda-mu calculus (classical natural deduction) by introducing non-idempotent union types. As in the intuitionistic case, non-idempotency allows us to extract quantitative information from the typing derivations and we obtain proofs of termination that are far more elementary than those in the idempotent case. These results leads us to define a small-step variant of the lambda-mu calculus, in which strong normalization is also characterized by means of quantitative methods.- In the second part of the dissertation, we extend the characterization of weak normalization in the pure lambda-calculus to an infinitary lambda-calculus narrowly related to Böhm trees, which was introduced by Klop et al. This gives a positive answer to a question known as Klop's problem. In that purpose, it is necessary to simultaneously introduce a system (system S) featuring infinite types and resorting to an intersection operator that we call sequential, and a validity criterion in order to discard unsound proofs that coinductive grammars give rise to. This also allows us to give a solution to TLCA problem #20 (type-theoretic characterization of hereditary permutations). It is to be noted that those two problem do not have a solution in the finite case (Tatsuta, 2007).- Finally, we study the expressive power of coinductive type grammars, without any validity criterion. We must once more resort to system S and we show that every term is typable in a non-trivial way with infinite types and that one can extract semantical information from those typings e.g. the order (arity) of any lambda-term. This leads us to introduce a method that allows typing totally unproductive terms (the so-called mute terms), which is inspired from first order logic. This result establishes that, in the coinductive extension of the relational model, every term has a non-empty interpretation. Using a similar method, we also prove that system S surjectively collapses on the set of points of this model
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