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  • 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.
361

Calibración de la función BPR en vías colectoras de Lima Metropolitana, basada en el caso de la avenida San Luis

Carbonell Remigio, Esmirna Géminis, García Vicente, Sergio Manuel 14 July 2020 (has links)
Para tomar decisiones sobre alternativas para reducir los efectos negativos de la congestión, se debe planificar el transporte. La planificación requiere, según el enfoque clásico, el conjunto secuencial de cuatro (04) modelos de transporte para tomar decisiones pertinentes. El cuarto y último modelo corresponde a la asignación de tráfico, el cual requiere de la función BPR. La función BPR (Bureau of Public Roads) estima el tiempo de viaje (Tf) respecto al flujo de transporte (V), a la capacidad (C), al tiempo de viaje en flujo libre (to) y a los parámetros (α y β), los cuales deben reflejan el desempeño de la infraestructura vial. En Lima Metropolitana, como en otras ciudades de Latinoamérica, suele emplearse valores estandarizados de α y β en la función BPR, esto significa que dichos valores no están ajustado a las condiciones actuales de la ciudad. A partir de ello, se genera incertidumbre en la estimación de los datos de salida de la función (tiempo de viaje) y en efecto, incertidumbre en la eficiencia de las decisiones para disminuir la congestión. El objetivo de la presente investigación es calibrar la función BPR, es decir, estimar los valores de α y β. Y, en consecuencia, asegurar que esta represente, de manera confiable, el comportamiento vial en Lima Metropolitana, específicamente en la vía colectora: Avenida San Luis. La metodología se desarrolla en tres (03) etapas: Levantamiento de información, determinación de los parámetros y análisis de los resultados. Como resultado de la calibración se obtiene valores de α=2.22 y β=1.19, y se demuestra que la función calibrada representa de forma adecuada los tiempos de viaje observados en la vía en estudio. En cambio, la utilización de valores estandarizados no resulta ser la mejor para dicha representación, y por el contrario, presenta errores significativos. / In order to take decisions about alternatives to reduce the congestion’s negative effects, transport must be planified. Planification requires, according to the classic approach, the four-model transport sequential set to take the pertinent decisions. The fourth and last model corresponds to the traffic allocation, that requires the BPR function. The BPR function (Bureau of Public Roads) estimates the travel time (Tf) regarding the transport’s flow (V), the capacity (C), the travel time in free flow (to) and the parameters (α y β), that reflect the performance of the road infraestructure. In the city of Lima, as in others Latinamerican cities, it is common to use standarised values of α and β in BPR function. That means that those values are not adjusted to the city’s current conditions. On that basis, uncertainty arises on the function of the data output (travel time) and also on the efficiency of the decisions taken to diminish the traffic congestion. The main approach of this investigation is to calibrate the BPR function, that means, to estimate the functions of α y β, and, because of it, ensure that this function represents the traffic behavoir in the city of Lima in a reliable way, specifically in the collector road: San Luis Avenue. The methodology is developed in three stages: gathering of information, determination of the parameters and analysis of the results. As a result of the calibration, the values obtained are α=2.22 and β=1.19, and it is demonstraded that the calibrated functions represent in a reliable way the travel times observed in the studied avenue. However, the use of standarised values is not the best one for such representation, and, on the contrary, it shows significative errors. / Tesis
362

Modeling Overlapping and Heterogeneous Perception Variance in Stochastic User Equilibrium Problem with Weibit Route Choice Model

Kitthamkersorn, Songyot 01 May 2013 (has links)
In this study, a new SUE model using the Weibull random error terms is proposed as an alternative to overcome the drawbacks of the multinomial logit (MNL) SUE model. A path-size weibit (PSW) model is developed to relax both independently and identically distributed assumptions, while retaining an analytical closed-form solution. Specifically, this route choice model handles route overlapping through the path-size factor and captures the route-specific perception variance through the Weibull distributed random error terms. Both constrained entropy-type and unconstrained equivalent MP formulations for the PSW-SUE are provided. In addition, model extensions to consider the demand elasticity and combined travel choice of the PSW-SUE model are also provided. Unlike the logit-based model, these model extensions incorporate the logarithmic expected perceived travel cost as the network level of service to determine the demand elasticity and travel choice. Qualitative properties of these minimization programs are given to establish equivalency and uniqueness conditions. Both path-based and link-based algorithms are developed for solving the proposed MP formulations. Numerical examples show that the proposed models can produce a compatible traffic flow pattern compared to the multinomial probit (MNP) SUE model, and these models can be implemented in a real-world transportation network.
363

Cooperative Multi-Agent UAS Task Assignment for Disaster Response Scenario

DeGroote, Nicholas January 2021 (has links)
No description available.
364

Quality-of-Service Control Scheme for Wireless Local Area Networks / 無線ローカルエリアネットワークにおける通信品質制御方式の研究

Nuno, Fusao 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18623号 / 情博第547号 / 新制||情||97(附属図書館) / 31523 / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 守倉 正博, 教授 高橋 達郎, 教授 梅野 健 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
365

Synthetic Studies of Peptide-Polyketide Hybrid Natural Products, Odoamide and Stereocalpin A / ペプチド─ポリケチド複合型天然物OdoamideおよびStereocalpin Aの合成研究

Kaneda, Masato 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第21049号 / 薬科博第92号 / 新制||薬科||10(附属図書館) / 京都大学大学院薬学研究科医薬創成情報科学専攻 / (主査)教授 大野 浩章, 教授 竹本 佳司, 教授 高須 清誠 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
366

VALUE-BASED FAULT LOCALIZATION IN JAVA NUMERICAL SOFTWARE WITH CAUSAL INFERENCE TECHNIQUE

Sheng, Jian 01 February 2019 (has links)
No description available.
367

Collocation of Data in a Multi-temperate Logical Data Warehouse

Martin, Bryan January 2019 (has links)
No description available.
368

A Biogeochemistry Approach to Geographic Origin and Mortuary Arrangement at the Talgua Cave Ossuaries, Olancho, Honduras

Warner, Monica Michelle 07 May 2016 (has links)
Isotopic assays, including stable carbon, stable oxygen, and radiogenic strontium were measured for 37 individuals from the Talgua cave ossuaries to understand human movement and mortuary practice during Formative Period Honduras. Likelihood assignment models demonstrated that the individuals had diverse childhood geographic origins within the surrounding valleys. This shows that different kin or ethnic groups from diverse geographic origins were utilizing the ossuaries. Five possible ‘non-local’ individuals were identified from the radiogenic strontium and stable oxygen isotope datasets, suggesting minimal human movement into northeast Honduras from outside Lower Central America. The low number of ‘non-local’ individuals at Talgua Caves also suggests that trade items were acquired by down-the-line exchange processes rather than through a long-distance trade connection. This type of trade network and bioarchaeological evidence of limited ‘non-local’ individuals at Talgua Caves suggests the surrounding region was culturally distinct from Mesoamerica during the Formative Period.
369

Using Stochastic and Deterministic Approaches for Integrating Freight Movement and Aircraft Taxiing to Solve the Gate Assignment Problem

Behrends, John A 12 August 2016 (has links)
With the increase in fuel prices, the efficient movement of aircraft around an airport can impact the profitability of a flight and an airline. The assignment of a flight to a specific gate not only impacts passenger satisfaction, but also impacts the efficient movement of aircraft from the departure gate to the runway. There have been bodies of research investigating aircraft taxi problems and gate assignment problems. However, each of these research bodies has not included the effects of the other research areas into their respective areas. This research presents a proposed framework that integrates the passenger or freight movement within a terminal with the taxiing of the aircraft to support an integrated approach to solving the gate assignment problem. A solution technique that incorporates a job shop scheduling solution method is presented and demonstrates that a large problem can be solved efficiently and in a short time using both deterministic and stochastic data.
370

Effects of Connected Vehicle Technology on Mobility and Mode Choice

Minelli, Simon 11 1900 (has links)
Connected vehicle is a fully connected transportation system in which vehicles, infrastructure, and mobile devices are enabled to exchange information in real-time to bring advancements in transportation operations. It is important to incorporate the new characteristics of the connected vehicle in the transportation planning process. Also, it is vital for planning and road agencies to better understand the impacts of connected vehicle on transportation networks, system demand, and travel behavior of road users in order to properly prepare for them. In addition, developers of connected vehicle systems can gain insight into how their systems will impact road users and network performance. When a change in performance of a transportation network occurs it can potentially cause users to change travel modes, known as mode choice. In this research, the change in mode choice, due to the change in network performance by introduction of connected vehicle is studied. This provides a more accurate depiction of the performance of the network and indicates how connected vehicles could change travellers’ preference in travel mode. The effect of this technology is explored on the performance of the Toronto waterfront, in a microsimulation environment. The results show that average travel time increases for high market penetrations when a dynamic route guidance algorithm is implemented, a phenomenon that occurs in dense, and complex traffic networks. Analysis of mode choice shows a loss in the auto mode share, for high market penetrations, due to the increased auto travel times. This loss in the auto mode share is compensated by increases in the other modes. / Thesis / Master of Applied Science (MASc)

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