Train scheduling and rolling stock assignment in high speed trains

The Train Timetabling Problem (TTP) has been widely studied for freight and passenger rail systems. A lesser effort has been devoted to the study of high-speed rail systems. A modeling issue that has to be addressed is to model departure time choice of passengers on railway services. Passengers who use these systems attempt to travel at predetermined hours due to their daily life necessities (e.g., commuter trips). We incorporate all these features into TTP focusing on high-speed railway systems. We propose a Rail Scheduling and Rolling Stock (RSch-RS) model for timetable planning of high-speed railway systems. This model is composed of two essential elements: i) an infrastructure model for representing the railway network: it includes capacity constraints of the rail network and the Rolling-Stock constraints; and ii) a demand model that defines how the passengers choose the departure time. The resulting model is a mixed-integer programming model which objective function attempts to maximize the profit for the rail operator

Análisis, dignóstico y propuesta para fomentar el destino turístico Bolivia enfocado al turismo emisivo de la ciudad de Cuenca, con la ruta que efrece LAN hacia La Paz y Santa Cruz 2015-2016

El presente trabajo de investigación tiene como objetivo conocer la oferta y demanda del mercado turístico emisivo hacia Bolivia desde la ciudad de Cuenca, con la finalidad de fomentar el turismo hacia nuevos destinos, enfocado principalmente en las ciudades de: La Paz y Santa Cruz de la Sierra, con la ruta que ofrece la aerolínea LAN hacia estos destinos. Para el desarrollo de la tesis se investigó el comportamiento de los pasajeros que deciden comprar los boletos en las oficinas de LAN, y las particularidades de las agencias de viajes que tienen convenio con la mencionada aerolínea, con la finalidad de determinar si existe un potencial mercado emisivo en la ciudad de Cuenca que esté dispuesto a visitar Bolivia; los resultados que se obtuvieron en este análisis definenprincipalmente la oferta y la demanda actual; adicionalmente se obtuvo la información necesaria de las agencias de viajes para informar y capacitar a los agentes de viajes, sobre los diferentes atractivos turísticos y sitios de interés con los que cuenta Bolivia; en base de toda ésta información, se propone la creación de diferentes paquetes con alternativas de turismo para los pasajeros en la ciudad de Cuenca. El aporte que se suministra con el desarrollo de ésta investigación, principalmente a las agencias de viajes y promotores turísticos es el de demostrar que se pueden ofertar lugares nuevos, que aún no han sido explotados en el mercado emisivo de la ciudad de Cuenca, para que no se limiten únicamente a competir por los productos de siempre previamente estructurados y saturados.

RESILIENCE OF NETWORKED INFRASTRUCTURE WITH EVOLVING COMPONENT CONDITIONS: A PAVEMENT NETWORK APPLICATION

This thesis deals with quantifying the resilience of a network of pavements. Calculations were carried out by modeling network performance under a set of possible damage-meteorological scenarios with known probability of occurrence. Resilience evaluation was performed a priori while accounting for optimal preparedness decisions and additional response actions that can be taken under each of the scenarios. Unlike the common assumption that the pre-event condition of all system components is uniform, fixed, and pristine, component condition evolution was incorporated herein. For this purpose, the health of the individual system components immediately prior to hazard event impact, under all considered scenarios, was associated with a serviceability rating. This rating was projected to reflect both natural deterioration and any intermittent improvements due to maintenance. The scheme was demonstrated for a hypothetical case study involving Laguardia Airport. Results show that resilience can be impacted by the condition of the infrastructure elements, their natural deterioration processes, and prevailing maintenance plans. The findings imply that, in general, upper bound values are reported in ordinary resilience work, and that including evolving component conditions is of value.

A Ride-Sharing System with High Capacity Vehicles and Flexible Meeting Points

In many major cities, fixed route transit systems such as bus and rail serve millions of trips per day. These systems have people collect at common locations (the station or stop), and board at common times (for example according to a predetermined schedule or headway). By using common service locations and times, these modes can consolidate many trips that have similar origins and destinations or overlapping routes. However, the routes are not sensitive to changing travel patterns, and have no way of identifying which trips are going unserved, or are poorly served, by the existing routes. On the opposite end of the spectrum, personal modes of transportation, such as a private vehicle or taxi, offer service to and from the exact origin and destination of a rider, at close to exactly the time they desire to travel. Despite the apparent increased convenience to users, the presence of a large number of small vehicles results in a disorganized, and potentially congested road network during high demand periods. The focus of the research presented in this paper is to develop a system that possesses both the on-demand nature of a personal mode, with the efficiency of shared modes. In this system, users submit their request for travel, but are asked to make small compromises in their origin and destination location by walking to a nearby meeting point, as well as slightly modifying their time of travel, in order to accommodate other passengers. Because the origin and destination location of the request can be adjusted, this is a more general case of the Dial-a-Ride problem with time windows. The solution methodology uses a graph clustering algorithm coupled with a greedy insertion technique. A case study is presented using actual requests for taxi trips in Washington DC, and shows a significant decrease in the number of vehicles required to serve the demand.

Configurando a cidade contemporânea em Natal : os processos espaciais em Ponta Negra

This dissertation is about the spatial configuration in Natal and processes in the Ponta Negra neighborhood today. Ponta Negra has undergone a number of critical social and spatial changes due to tourism development after the 1990s. It is of special interest to consider the intensification of real estate investment after 2000, when the new airport terminal, located in the neighboring municipality of Parnamirim, was in use. Ponta Negra is the place where most tourists go to, so attracting considerable public investments. New agents of transformation have produced change in the neighborhood as well. The present study aims at analysing the spatial processes in this part of the city. Here, the spatial configuration that resulted from extended real estate investments, both public and private, in recent years, is analysed in detail. The study identifies the multually differentiated, however internally homogenous areas. The concepts of production of space, contemporanean urban development and spatial dynamics are discussed. The research is based on document analysis and field work. Results were plotted to maps and tables. A detailed analysis of the spatial processes in the Ponta Negra neighborhood is undertaken as a conclusion, considering the contemporanean global scenario

On the optimaL response of q-vortex

Wingtip vortices represent a hazard for the stability of the following airplane in airport highways. These flows have been usually modeled as swirling jets/wakes, which are known to be highly unstable and susceptible to breakdown at high Reynolds numbers for certain flow conditions, but different to the ones present in real flying airplanes. A very recent study based on Direct Numerical Simulations (DNS) shows that a large variety of helical responses can be excited and amplified when a harmonic inlet forcing is imposed. In this work, the optimal response of q-vortex (both axial vorticity and axial velocity can be modeled by a Gaussian profile) is studied by considering the time-harmonically forced problem with a certain frequency ω. We first reproduce Guo and Sun’s results for the Lamb-Oseen vortex (no axial flow) to validate our numerical code. In the axisymmetric case m = 0, the system response is the largest when the input frequency is null. The axial flow has a weak influence in the response for any axial velocity intensity. We also consider helical perturbations |m| = 1. These perturbations are excited through a resonance mechanism at moderate and large wavelengths as it is shown in Figure 1. In addition, Figure 2 shows that the frequency at which the optimal gain is obtained is not a continuous function of the axial wavenumber k. At smaller wavelengths, large response is excited by steady forcing. Regarding the axial flow, the unstable response is the largest when the axial velocity intensity, 1/q, is near to zero. For perturbations with higher azimuthal wavenumbers |m| > 1, the magnitudes of the response are smaller than those for helical modes. In order to establish an alternative validation, DNS has been carried out by using a pseudospectral Fourier formulation finding a very good agreement.

Motivating the use of public transit through a mobile glanceable display

With increasing concerns about the impact of global warming on human life, policy makers around the world and researchers have sought for technological solutions that have the potential to attenuate this process. This thesis describes the design and evaluation of an information appliance that aims to increase the use of public transportation. We developed a mobile glanceable display that, being aware of the user’s transportation routines, provides awareness cues about bus arrival time, grounded upon the vision of Ambient Intelligence. We present the design process we followed, from ideation to building a prototype and conducting a field study, and conclude with a set of guidelines for the design of relevant personal information systems. More specifically we seek to test the following hypotheses: 1) That the tangible prototype that provides ambient cues will be used more frequently than a similar purpose mobile app, 2) That the tangible prototype will reduce the waiting time at the bus stop, 3) That the tangible prototype will result to reduced anxiety on passengers, 4) That the tangible prototype will result to an increase in the perceived reliability of the transit service, 5) That the tangible prototype will enhance users’ efficiency in reading the bus schedules and 6) That the tangible prototype will make individuals more likely to use public transit. In a field study, we compare the tangible prototype against the mobile app and a control condition where participants were given no external support in obtaining bus arrival information, other than their existing routines. Using qualitative and quantitative data, we test the aforementioned hypotheses and explore users’ reactions to the prototype we developed.

Measuring QoS in an aeronautical opportunistic network architecture with limited access to a satellite communications backhaul

We measure quality of service (QoS) in a wireless network architecture of transoceanic aircraft. A distinguishing characteristic of the network scheme we analyze is that it mixes the concept of Delay Tolerant Networking (DTN) through the exploitation of opportunistic contacts, together with direct satellite access in a limited number of the nodes. We provide a graph sparsification technique for deriving a network model that satisfies the key properties of a real aeronautical opportunistic network while enabling scalable simulation. This reduced model allows us to analyze the impact regarding QoS of introducing Internet-like traffic in the form of outgoing data from passengers. Promoting QoS in DTNs is usually really challenging due to their long delays and scarce resources. The availability of satellite communication links offers a chance to provide an improved degree of service regarding a pure opportunistic approach, and therefore it needs to be properly measured and quantified. Our analysis focuses on several QoS indicators such as delivery time, delivery ratio, and bandwidth allocation fairness. Obtained results show significant improvements in all metric indicators regarding QoS, not usually achievable on the field of DTNs.

Tráfico de droga nos aeroportos

Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de licenciada em Criminologia

Motivating the use of public transit through a mobile glanceable display

With increasing concerns about the impact of global warming on human life, policy makers around the world and researchers have sought for technological solutions that have the potential to attenuate this process. This thesis describes the design and evaluation of an information appliance that aims to increase the use of public transportation. We developed a mobile glanceable display that, being aware of the user’s transportation routines, provides awareness cues about bus arrival time, grounded upon the vision of Ambient Intelligence. We present the design process we followed, from ideation to building a prototype and conducting a field study, and conclude with a set of guidelines for the design of relevant personal information systems. More specifically we seek to test the following hypotheses: 1) That the tangible prototype that provides ambient cues will be used more frequently than a similar purpose mobile app, 2) That the tangible prototype will reduce the waiting time at the bus stop, 3) That the tangible prototype will result to reduced anxiety on passengers, 4) That the tangible prototype will result to an increase in the perceived reliability of the transit service, 5) That the tangible prototype will enhance users’ efficiency in reading the bus schedules and 6) That the tangible prototype will make individuals more likely to use public transit. In a field study, we compare the tangible prototype against the mobile app and a control condition where participants were given no external support in obtaining bus arrival information, other than their existing routines. Using qualitative and quantitative data, we test the aforementioned hypotheses and explore users’ reactions to the prototype we developed.

Maleta pequeña y relatos cortos: Crónicas de un viajero

Este trabajo de grado es un conjunto de crónicas que carácter experiencial, desde las cuales se narran las historias que viven los turistas en sitios inhóspitos como el desierto de la Tatacoa y la selva del Amazonas. Estos textos están orientados a mostrar el desarrollo del periodismo de turismo en Colombia.

Planos nacionais de controlo dos géneros alimentícios

Este relatório descreve as atividades desenvolvidas durante o estágio curricular do curso de Mestrado Integrado em Medicina Veterinária no âmbito da inspeção sanitária e saúde pública, realizado tanto nos PIF de Lisboa, como na Divisão de Riscos Alimentares (DRA) da Autoridade de Segurança Alimentar e Económica (ASAE). Existe uma grande variedade de produtos e animais que chegam diariamente à União Europeia provenientes de diferentes países terceiros, como por exemplo a China, África do Sul, Brasil, Índia, Canadá e Senegal. Durante o período de estágio a categoria dos produtos mais inspecionada nos PIF foi o pescado representando 57,5% da totalidade das remessas inspecionadas nos portos de Lisboa e 98% no aeroporto. No âmbito do plano de fiscalização da ASAE em 2015, a aluna analisou 365 amostras de géneros alimentícios e constatou-se que o número de amostras não conformes foi 254. O grupo das bebidas alcoólicas destacou-se com 159 amostras não conformes; Abstract: National Control Plans of Food This essay describes the activities developed throughout the curricular internship of the Integrated Master of Veterinary Medicine within sanitary inspection and public health, both at border control of Lisbon as well as in the Divisão de Riscos Alimentares (DRA) of the Autoridade de Segurança Alimentar e Económica (ASAE). There is a wide variety of products and animals that arrive daily to the European Union from third countries, such as China, South Africa, Brazil, India, Canada and Senegal. During the internship the largest category of inspected food was fish representing 57.5% of the inspected remittances in the port of Lisbon and 98% in the airport. As part of the fiscalization plan of ASAE in 2015 the student analysed 365 food samples and it was found that the number of samples non-conforming was 254. The ardent spirits was the category that stood out with 159 non-conforming samples (63%).

El salvamento del Mural de la Segunda República: recuperar el patrimonio y la memoria histórica de un pueblo

La decisión de realizar este trabajo, cuyo objetivo fue salvar y dar a conocer el Mural de la Segunda República, fue tomada después de analizar la situación de esta obra-mural de Lucio Ranucci, elaborada en 1954, para el gobierno de Costa Rica en el Aeropuerto Internacional El Coco (actual Aeropuerto Internacional Juan Santamaría).Este mural estaba en peligro de perderse, pues la empresa concesionaria para la construcción y remodelación del aeropuerto iba a demoler el edificio que por más de 48 años, había albergado esta obra y hasta ese momento nadie se había preocupado por su suerte. AbstractThe decision to undertake this work, aimed at rescuing and bringing to light the Mural de la Segunda República, was taken after carefully analyzing the conditions of this masterpiece, a mural painted, by request of the Costa Rican government, in 1954 by Lucio Ranucci at the El Coco Airport, today known as Juan Santamaría International Airport. This mural was in danger, since the contracting company for the building and remodeling of the new airport was about to demolish the building that have had hosted work of art for over 48 years. Up to then no one had shown interest in its relocation.