• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 175
  • 57
  • 31
  • 29
  • 16
  • 11
  • 6
  • 5
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 429
  • 71
  • 46
  • 38
  • 36
  • 32
  • 29
  • 28
  • 27
  • 26
  • 26
  • 26
  • 25
  • 25
  • 23
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Análisis del impacto vial producido por el establecimiento de un edificio multifamiliar de 20 pisos y 80 estacionamientos ubicado en la Avenida Arequipa utilizando el modelo de microsimulación de Wiedemann 74 / Analysis of the road impact produced by the establishment of a 20-story and 80-parking multifamily building located on Avenue Arequipa using Wiedemann 74 microsimulation model

Marin Flores, Alvaro Manuel, Enero Quispe, Robin Alejandro 28 January 2020 (has links)
La presente tesis propone una solución a la congestión vehicular ocasionado por el establecimiento de un proyecto multifamiliar a través de propuestas de mejora en la infraestructura vial, la cual reducirá las demoras por control y optimizará los niveles de servicio por medio de los parámetros de diseño del modelo de microsimulación de Wiedemann 74. En el primer capítulo contextualiza la problemática del tema de investigación, antecedentes de estudios, justificativa, hipótesis, objetivos y limitaciones de la investigación. En el segundo capítulo se desarrolla el marco teórico que respalda los criterios con los que se desarrollará el modelo de microsimulación y la propuesta de mejora. Se define los tipos de modelos de tránsito, los fundamentos de la microsimulación y conceptos que serán importantes al momento de realizar el análisis de resultados. El tercer capítulo describe la metodología que se utiliza desde la recolección de datos de campo hasta el modelo de microsimulación debidamente calibrado y validado. Además, se detalla la elaboración del modelo de microsimulación. En el cuarto capítulo se presentan el análisis de resultados obtenidos en la situación actual, en la situación del proyecto a 5 años sin implementar las propuestas de mejora y luego, se presentan las medidas de mitigación a los impactos negativos, los cuales involucra el diseño de la infraestructura vial y reajuste en los ciclos semafóricos. En el último capítulo se encontrarán las conclusiones y recomendaciones a las que se llegaron respondiendo así el objetivo general de la presente tesis. / This thesis proposes a solution to vehicular congestion caused by the establishment of a multi-family project through proposals for improvement in road infrastructure, which will reduce delays in control and optimize service levels through the design parameters of the Wiedemann microsimulation model 74. In the first chapter, it contextualizes the problems of the research topic, study background, justification, hypotheses, objectives and limitations of the research. In the second chapter, the theoretical framework that supports the criteria with which the microsimulation model will be developed and the improvement proposal will be developed. It defines the types of traffic models, the fundamentals of microsimulation and concepts that will be important when performing the results analysis. The third chapter describes the methodology used from the field data collection to the properly calibrated and validated microsimulation model. In addition, the elaboration of the microsimulation model is detailed. In the fourth chapter, the analysis of results obtained in the current situation is presented, in the situation of the project 5 years without implementing the improvement proposals and then, the mitigation measures to the negative impacts are presented, which involves the design of road infrastructure and readjustment in traffic light cycles. In the last chapter you will find the conclusions and recommendations that were reached thus responding to the general objective of this thesis. / Tesis
32

Stabbing and separation

Wenger, Rephael January 1988 (has links)
No description available.
33

Automatic System to Measure Turning Movements and Intersection Delay

Mao, Jialei 09 June 2009 (has links)
No description available.
34

A Computational Hybrid Method for Self-Intersection Free Offsetting of CAD Geometry

Bodily, Garrett Clark 01 July 2014 (has links) (PDF)
Surface offsetting is a valuable tool used in Computer Aided Design (CAD). An offset surface is a collection of points that are at a constant distance from another surface. An offset surface is created in CAD by selecting a surface and then specifying the distance that the surface is to be offset. If a surface is selected and a distance of D is specified, then the resulting offset surface should always be distance D from the original surface. The surface offset tool can be used for many applications. Modeling of composites or other layered manufacturing processes rely heavily on offset surfaces. Thin walled parts such as injection molded components are often modeled using the offset tool. Coating processes can also be modeled using the offset tool. Modern CAD systems have surface offsetting tools and are widely used throughout industry. However, CAD systems often fail to produce valid results. The process of surface offsetting can often result in surface self-intersections as well as surface degeneracies. Self-intersections and degeneracies make the surfaces invalid because they are physically impossible to create and CAD systems cannot use these invalid surfaces to represent solid bodies. The surface offset tool is therefore, one of the most challenging CAD tools to implement. The process of avoiding, detecting and removing surface self-intersections is extremely challenging. Much research in the field of CAD is dedicated to the detection and removal of surface self-intersections. However, the methods proposed in the literature all suffer from robustness problems. The purpose of this research is to introduce a method that creates valid offset surfaces and does not suffer from the problem of creating surface self-intersections. This method uses a numerical approach that approximates the offset surface and avoids all self-intersections. Because no self-intersections are created, the method does not require intersection tests of any kind. The value of this method is demonstrated by comparing its results with results from leading CAD systems.
35

Characteristic and Order for Polynomial Differentiability

Gupta, Meera 10 1900 (has links)
<p> A definition of polynomial differentiability of an arc in the real affine plane at a point is given. The differentiable points are classified with respect to the intersection and support properties of certain families of osculating polynomials. For a given point of an arc, these properties are used to define a certain n-tuple of integers, the characteristic of that point. It is shown that the polynomial order of polynomially differentiable interior point of an arc is at least as great as the sum of the digits of its characteristic.</p> / Thesis / Doctor of Philosophy (PhD)
36

Fast Gaussian Evaluations in Large Vocabulary Continous Speech Recognition

Srivastava, Shivali 13 December 2002 (has links)
Rapid advances in speech recognition theory, as well as computing hardware, have led to the development of machines that can take human speech as input, decode the information content of the speech, and respond accordingly. Real-time performance of such systems is often dominated by the evaluation of likelihoods in the statistical modeling component of the system. Statistical models are typically implemented using Gaussian mixture distributions. The primary objective of this thesis was to develop an extension of the Bucket Box Intersection algorithm in which the dimension with the optimal number of splits can be selected when multiple minima are present. The effects of normalization of mixture weights and Gaussian clipping have also been investigated. We show that the Extended BBI algorithm (EBBI) reduces run-time by 21% without introducing any approximation error. EBBI also produced a 12% lower word error rate than Gaussian clipping for the same computational complexity. These approaches were evaluated on a wide variety of tasks including conversational speech.
37

Development of a Threat Assessment Algorithm for Intersection Collision Avoidance Systems

Doerzaph, Zachary R. 11 February 2008 (has links)
Relative to other roadway segments, intersections occupy a small portion of the overall infrastructure; however, they represent the location for nearly 41 % of the annual automotive crashes in the United States. Thus, intersections are an inherently dangerous roadway element and a prime location for vehicle conflicts. Traditional safety treatments are effective at addressing certain types of intersection safety deficiencies; however, cumulative traffic data suggests these treatments do not address a large portion of the crashes that occur each year. Intersection Collision Avoidance Systems (ICAS) represent a new breed of countermeasures that focus on the types of crashes that have not been reduced with the application of traditional methods. Incursion systems, a subset of ICAS, are designed to specifically undertake crashes that are a result of the violation of a traffic control device. Intersection Collision Avoidance Systems to address Violations (ICAS-V) monitor traffic as it approaches the intersection through a network of in-vehicle sensors, infrastructure- mounted sensors, and communication equipment. A threat-assessment algorithm performs computations to predict the driver's intended intersection maneuver, based on these sensor inputs. If the system predicts a violation, it delivers a timely warning to the driver with the aim of compelling the driver to stop. This warning helps the driver to avoid a potential crash with adjacent traffic. The following dissertation describes an investigation of intersection approach behavior aimed at developing a threat assessment algorithm for stop-sign intersections. Data were collected at live intersections to gather infrastructure-based naturalistic vehicle approach trajectories. This data were compiled and analyzed with the goal of understanding how drivers approach intersections under various speeds and environmental conditions. Six stop-controlled intersection approaches across five intersections in the New River Valley, Virginia area were selected as the test sites. Data were collected from each site for at least two months, resulting in over sixteen total months of data. A series of statistical analysis techniques were applied to construct a set of threat assessment algorithms for stop-controlled intersections. These analyses identified characteristics of intersection approaches that suggested driver intent at the stop sign. Models were constructed to predict driver stopping intent based on measured vehicle kinematics. These models were thoroughly tested using simulation and evaluated with signal detection theory. The overall output of this work is a set of algorithms that may be integrated into an ICAS-V for on-road testing. / Ph. D.
38

Designing is Cooking: A Museum of Gastronomy

Lam, 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
39

On Projective Planes & Rational Identities

Brunson, 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
40

Travel Time Estimation on Arterial Streets

Wang, Heng 30 December 2004 (has links)
Estimation of real-time travel times on arterial streets has been a challenging task due to the intersection control delay as well as bottleneck delay from the downstream link. Therefore, few transportation professionals have conducted research at utilizing the dynamic flow methods to estimate travel times on arterial street networks. This thesis is to develop dynamic flow algorithms that estimates the real-time travel time on an arterial street network by utilizing the traffic information obtained from detectors. A modified method to the one adopted in HCM2000 in computing the intersection control delay is developed and utilized to estimate the real-time travel time for a short-time interval update under non-incident and incident situations. Simulation model is developed in CORSIM to validate developed algorithms under different traffic situations. / Master of Science

Page generated in 0.1121 seconds