955 resultados para Portland (Vic.) -- Description and travel


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La planificación y las políticas de transporte no pueden descuidar la calidad del servicio, considerando que influye notablemente en el cambio modal del coche hacia otros medios de transporte más sostenibles. El concepto se aplica también a los intercambiadores de transporte público, los nodos del sistema donde se cruzan las distintas redes del transporte público y privado. Aunque se han logrado numerosos avances para medir y evaluar la calidad en el sector del transporte público, se han dedicado relativamente pocos esfuerzos a investigar estos aspectos relacionados con la calidad de los intercambiadores del transporte público. Este trabajo de investigación se concentra en la calidad del servicio de la transferencia modal en los intercambiadores interurbanos, según la perspectiva de los viajeros. Su objetivo es identificar los factores clave de la calidad del servicio y los perfiles de los viajeros en los intercambiadores. La investigación es exploratoria y ofrece información acerca de la percepción de los viajeros intermodales relacionada con los aspectos de la calidad, aportando nuevos elementos y datos para adentrarse en estudios más detallados. La metodología del trabajo combina técnicas de análisis estadístico multivariante para analizar los datos de las encuestas sobre la satisfacción de los clientes y se subdivide en tres etapas. En primer lugar, se ha implementado el análisis de correspondencias múltiples para explorar los constructos latentes relacionados con la satisfacción de las características cualitativas de los intercambiadores interurbanos, identificando así los factores clave de la calidad. En segundo lugar, se ha aplicado un análisis de conglomerados de k-medias sobre los factores clave de calidad para clasificar a los viajeros en grupos de usuarios de transportes homogéneos, de acuerdo con su percepción de satisfacción, identificando de este modo los perfiles de los viajeros. Por último, se han formulado sugerencias y recomendaciones sobre la calidad para respaldar la formulación de políticas, estableciendo las prioridades para los intercambiadores interurbanos. La metodología se aplicó en cuatro intercambiadores interurbanos (estaciones de ferrocarriles o de autobuses ) en Madrid, Zaragoza, Gothenburg y Lion, analizando los datos recogidos mediante una encuesta de satisfacción del cliente llevada a cabo en 2011 en los cuatro casos de estudio, donde se interconectan distintos medios de transporte público y privado, de corta y larga distancia. Se recogieron datos sobre la satisfacción de los viajeros con 26 criterios de calidad, así como información sobre aspectos socio-económicos y pautas de comportamiento de viajes. Mediante el análisis de correspondencias múltiples se identificaron 4-5 factores clave de calidad en cada intercambiador, que se asocian principalmente con el sistema de emisión de billetes, el confort y la interconexión, mientras que los viajeros no perciben los temas clásicos como la información. Mediante el análisis de conglomerados se identificaron 2-5 perfiles de viajeros en cada intercambiador. Se reconocieron dos grupos de viajeros en casi todos los casos de estudio: viajeros de cercanía/trabajadores y turistas. Por lo que concierne a las prioridades para apoyar a las partes interesadas en la formulación de políticas, la expedición de billetes es el factor clave para los intercambiadores interurbanos españoles, mientras que la interconexión y los aspectos temporales se destacan en los intercambiadores de Francia y Suecia. Quality of Service can not be neglected in public transport planning and policy making, since it strongly influences modal shifts from car to more sustainable modes. This concept is also related to Public Transport interchanges, the nodes of the transport system where the different sub-systems of public passenger transport and personal vehicles meet. Although a lot of progress has been generally done to measure and assess quality in public transport sector, relatively little investigation has been conducted on quality at PT interchanges. This research work focusses on Quality of Service in the use of transfer facilities at interurban interchanges, according to current travellers’ perspective. It aims at identifying key quality factors and travellers profiles at interurban interchanges. The research is exploratory and offers insight into intermodal travellers’ perception on quality aspects, providing new elements and inputs for more definitive investigation. The methodology of the work combines multivariate statistical techniques to analyse data from customer satisfaction surveys and is subdivided in three steps. Firstly, multiple correspondence analysis was performed to explore latent constructs as concern satisfaction of quality attributes at interurban interchanges, thus identifying the so-called Key Quality Factor. Secondly, k-means cluster analysis was implemented on the key quality factors to classify travellers in homogeneous groups of transport users, according to their perception of satisfaction, thus identifying the so-called Travellers Profiles. Finally, hints and recommendations on quality were identified to support policy making, setting priorities for interurban interchanges. The methodology was applied at four interurban interchanges in Madrid, Zaragoza, Gothenburg and Lyon, analysing the data collected through a customer satisfaction survey carried out in 2011 at the four railway or bus stations where different modes of public and private transport are interconnected covering both short and long trips. Data on travellers’ satisfaction with 26 quality attributes were collected, as well as information on socio-economical and travel patterns. Through multiple correspondence analysis were identified 4-5 key quality factors per interchange. They are mainly related to ticketing, comfort and connectivity, while classical issues, as information, are not perceived as important by travellers’. Through cluster analysis were identified 2-5 travellers profiles per interchange. Two groups of travellers can be found in almost all case studies: commuter / business travellers and holiday travellers. As regards the priorities to support stakeholders in policy making, ticketing is the key-issue for the Spanish interurban interchanges, while connectivity and temporal issues emerge in the French and Swedish case studies.

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Neighbourhood representation and scale used to measure the built environment have been treated in many ways. However, it is anything but clear what representation of neighbourhood is the most feasible in the existing literature. This paper presents an exhaustive analysis of built environment attributes through three spatial scales. For this purpose multiple data sources are integrated, and a set of 943 observations is analysed. This paper simultaneously analyses the influence of two methodological issues in the study of the relationship between built environment and travel behaviour: (1) detailed representation of neighbourhood by testing different spatial scales; (2) the influence of unobserved individual sensitivity to built environment attributes. The results show that different spatial scales of built environment attributes produce different results. Hence, it is important to produce local and regional transport measures, according to geographical scale. Additionally, the results show significant sensitivity to built environment attributes depending on place of residence. This effect, called residential sorting, acquires different magnitudes depending on the geographical scale used to measure the built environment attributes. Spatial scales risk to the stability of model results. Hence, transportation modellers and planners must take into account both effects of self-selection and spatial scales.

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In recent years, the increasing sophistication of embedded multimedia systems and wireless communication technologies has promoted a widespread utilization of video streaming applications. It has been reported in 2013 that youngsters, aged between 13 and 24, spend around 16.7 hours a week watching online video through social media, business websites, and video streaming sites. Video applications have already been blended into people daily life. Traditionally, video streaming research has focused on performance improvement, namely throughput increase and response time reduction. However, most mobile devices are battery-powered, a technology that grows at a much slower pace than either multimedia or hardware developments. Since battery developments cannot satisfy expanding power demand of mobile devices, research interests on video applications technology has attracted more attention to achieve energy-efficient designs. How to efficiently use the limited battery energy budget becomes a major research challenge. In addition, next generation video standards impel to diversification and personalization. Therefore, it is desirable to have mechanisms to implement energy optimizations with greater flexibility and scalability. In this context, the main goal of this dissertation is to find an energy management and optimization mechanism to reduce the energy consumption of video decoders based on the idea of functional-oriented reconfiguration. System battery life is prolonged as the result of a trade-off between energy consumption and video quality. Functional-oriented reconfiguration takes advantage of the similarities among standards to build video decoders reconnecting existing functional units. If a feedback channel from the decoder to the encoder is available, the former can signal the latter changes in either the encoding parameters or the encoding algorithms for energy-saving adaption. The proposed energy optimization and management mechanism is carried out at the decoder end. This mechanism consists of an energy-aware manager, implemented as an additional block of the reconfiguration engine, an energy estimator, integrated into the decoder, and, if available, a feedback channel connected to the encoder end. The energy-aware manager checks the battery level, selects the new decoder description and signals to build a new decoder to the reconfiguration engine. It is worth noting that the analysis of the energy consumption is fundamental for the success of the energy management and optimization mechanism. In this thesis, an energy estimation method driven by platform event monitoring is proposed. In addition, an event filter is suggested to automate the selection of the most appropriate events that affect the energy consumption. At last, a detailed study on the influence of the training data on the model accuracy is presented. The modeling methodology of the energy estimator has been evaluated on different underlying platforms, single-core and multi-core, with different characteristics of workload. All the results show a good accuracy and low on-line computation overhead. The required modifications on the reconfiguration engine to implement the energy-aware manager have been assessed under different scenarios. The results indicate a possibility to lengthen the battery lifetime of the system in two different use-cases.

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This study investigates the effect of price and travel mode fairness and spatial equity in transit provision on the perceived transit service quality, willingness to pay, and habitual frequency of use. Based on the theory of planned behavior, we developed a web-based questionnaire for revealed preferences data collection. The survey was administered among young people in Copenhagen and Lisbon to explore the transit perceptions and use under different economic and transit provision conditions. The survey yielded 499 questionnaires, analyzed by means of structural equation models. Results show that higher perceived fairness relates positively to higher perceived quality of transit service and higher perceived ease of paying for transit use. Higher perceived spatial equity in service provision is associated with higher perceived service quality. Higher perceived service quality relates to higher perceived ease of payment, which links to higher frequency of transit use.

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En los últimos años, el Ge ha ganado de nuevo atención con la finalidad de ser integrado en el seno de las existentes tecnologías de microelectrónica. Aunque no se le considera como un canddato capaz de reemplazar completamente al Si en el futuro próximo, probalemente servirá como un excelente complemento para aumentar las propiedades eléctricas en dispositivos futuros, especialmente debido a su alta movilidad de portadores. Esta integración requiere de un avance significativo del estado del arte en los procesos de fabricado. Técnicas de simulación, como los algoritmos de Monte Carlo cinético (KMC), proporcionan un ambiente atractivo para llevar a cabo investigación y desarrollo en este campo, especialmente en términos de costes en tiempo y financiación. En este estudio se han usado, por primera vez, técnicas de KMC con el fin entender el procesado “front-end” de Ge en su fabricación, específicamente la acumulación de dañado y amorfización producidas por implantación iónica y el crecimiento epitaxial en fase sólida (SPER) de las capas amorfizadas. Primero, simulaciones de aproximación de clisiones binarias (BCA) son usadas para calcular el dañado causado por cada ión. La evolución de este dañado en el tiempo se simula usando KMC sin red, o de objetos (OKMC) en el que sólamente se consideran los defectos. El SPER se simula a través de una aproximación KMC de red (LKMC), siendo capaz de seguir la evolución de los átomos de la red que forman la intercara amorfo/cristalina. Con el modelo de amorfización desarrollado a lo largo de este trabajo, implementado en un simulador multi-material, se pueden simular todos estos procesos. Ha sido posible entender la acumulación de dañado, desde la generación de defectos puntuales hasta la formación completa de capas amorfas. Esta acumulación ocurre en tres regímenes bien diferenciados, empezando con un ritmo lento de formación de regiones de dañado, seguido por una rápida relajación local de ciertas áreas en la fase amorfa donde ambas fases, amorfa y cristalina, coexisten, para terminar en la amorfización completa de capas extensas, donde satura el ritmo de acumulación. Dicha transición ocurre cuando la concentración de dañado supera cierto valor límite, el cual es independiente de las condiciones de implantación. Cuando se implantan los iones a temperaturas relativamente altas, el recocido dinámico cura el dañado previamente introducido y se establece una competición entre la generación de dañado y su disolución. Estos efectos se vuelven especialmente importantes para iones ligeros, como el B, el cual crea dañado más diluido, pequeño y distribuido de manera diferente que el causado por la implantación de iones más pesados, como el Ge. Esta descripción reproduce satisfactoriamente la cantidad de dañado y la extensión de las capas amorfas causadas por implantación iónica reportadas en la bibliografía. La velocidad de recristalización de la muestra previamente amorfizada depende fuertemente de la orientación del sustrato. El modelo LKMC presentado ha sido capaz de explicar estas diferencias entre orientaciones a través de un simple modelo, dominado por una única energía de activación y diferentes prefactores en las frecuencias de SPER dependiendo de las configuraciones de vecinos de los átomos que recristalizan. La formación de maclas aparece como una consecuencia de esta descripción, y es predominante en sustratos crecidos en la orientación (111)Ge. Este modelo es capaz de reproducir resultados experimentales para diferentes orientaciones, temperaturas y tiempos de evolución de la intercara amorfo/cristalina reportados por diferentes autores. Las parametrizaciones preliminares realizadas de los tensores de activación de tensiones son también capaces de proveer una buena correlación entre las simulaciones y los resultados experimentales de velocidad de SPER a diferentes temperaturas bajo una presión hidrostática aplicada. Los estudios presentados en esta tesis han ayudado a alcanzar un mejor entendimiento de los mecanismos de producción de dañado, su evolución, amorfización y SPER para Ge, además de servir como una útil herramienta para continuar el trabajo en este campo. In the recent years, Ge has regained attention to be integrated into existing microelectronic technologies. Even though it is not thought to be a feasible full replacement to Si in the near future, it will likely serve as an excellent complement to enhance electrical properties in future devices, specially due to its high carrier mobilities. This integration requires a significant upgrade of the state-of-the-art of regular manufacturing processes. Simulation techniques, such as kinetic Monte Carlo (KMC) algorithms, provide an appealing environment to research and innovation in the field, specially in terms of time and funding costs. In the present study, KMC techniques are used, for the first time, to understand Ge front-end processing, specifically damage accumulation and amorphization produced by ion implantation and Solid Phase Epitaxial Regrowth (SPER) of the amorphized layers. First, Binary Collision Approximation (BCA) simulations are used to calculate the damage caused by every ion. The evolution of this damage over time is simulated using non-lattice, or Object, KMC (OKMC) in which only defects are considered. SPER is simulated through a Lattice KMC (LKMC) approach, being able to follow the evolution of the lattice atoms forming the amorphous/crystalline interface. With the amorphization model developed in this work, implemented into a multi-material process simulator, all these processes can be simulated. It has been possible to understand damage accumulation, from point defect generation up to full amorphous layers formation. This accumulation occurs in three differentiated regimes, starting at a slow formation rate of the damage regions, followed by a fast local relaxation of areas into the amorphous phase where both crystalline and amorphous phases coexist, ending in full amorphization of extended layers, where the accumulation rate saturates. This transition occurs when the damage concentration overcomes a certain threshold value, which is independent of the implantation conditions. When implanting ions at relatively high temperatures, dynamic annealing takes place, healing the previously induced damage and establishing a competition between damage generation and its dissolution. These effects become specially important for light ions, as B, for which the created damage is more diluted, smaller and differently distributed than that caused by implanting heavier ions, as Ge. This description successfully reproduces damage quantity and extension of amorphous layers caused by means of ion implantation reported in the literature. Recrystallization velocity of the previously amorphized sample strongly depends on the substrate orientation. The presented LKMC model has been able to explain these differences between orientations through a simple model, dominated by one only activation energy and different prefactors for the SPER rates depending on the neighboring configuration of the recrystallizing atoms. Twin defects formation appears as a consequence of this description, and are predominant for (111)Ge oriented grown substrates. This model is able to reproduce experimental results for different orientations, temperatures and times of evolution of the amorphous/crystalline interface reported by different authors. Preliminary parameterizations for the activation strain tensors are able to also provide a good match between simulations and reported experimental results for SPER velocities at different temperatures under the appliance of hydrostatic pressure. The studies presented in this thesis have helped to achieve a greater understanding of damage generation, evolution, amorphization and SPER mechanisms in Ge, and also provide a useful tool to continue research in this field.

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We present a method for predicting protein folding class based on global protein chain description and a voting process. Selection of the best descriptors was achieved by a computer-simulated neural network trained on a data base consisting of 83 folding classes. Protein-chain descriptors include overall composition, transition, and distribution of amino acid attributes, such as relative hydrophobicity, predicted secondary structure, and predicted solvent exposure. Cross-validation testing was performed on 15 of the largest classes. The test shows that proteins were assigned to the correct class (correct positive prediction) with an average accuracy of 71.7%, whereas the inverse prediction of proteins as not belonging to a particular class (correct negative prediction) was 90-95% accurate. When tested on 254 structures used in this study, the top two predictions contained the correct class in 91% of the cases.

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Special foundations, most prominently micropiles and soil anchors, are frequently used in construction today. In Spain, the grout for these special technical applications is generally prepared with portland cement, although the codes and standards in place stipulate only the minimum compressive strength required, with no mention of cement type. Those texts also establish a range of acceptable water:cement ratios. In the present study, durability and compressive strength in cement grout prepared with blast furnace slag cement at different w/c ratios are characterised and compared to the findings for a reference portland cement grout. The results show that slag grout exhibits greater durability than the portland cement material and complies with the compressive strength requirements laid down in the respective codes.

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Almanac with sporadic annotations on the calendar pages and interleaved with entries in John Winthrop's hand for the months of January-April. The entries record Winthrop's social engagements and travel, with only occasional notes of the weather. There is also a folded interleaved leaf after the December page with scientific observations and a description of the Boston massacre (March 5).

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Almanac containing interleaved pages and sporadic annotations on the calendar pages by John Winthrop. The calendar pages are typically annotated with one or two notes at the bottom recording household activities. The interleaved pages contain entries with almost daily notes of social engagements and travel during the year. One interleaved leaf contains short miscellaneous entries about local deaths including the death and funeral of Harvard Tutor John Wadsworth (July 12), Revolutionary war battles, an illness (May 27), a description of changing currency (June 27), Doctor Doddridge's epigram "Dum vivimus vivamus" beginning "'Live while you live,' the Epicure will say...", and a short list of legal activities such as citations and wills performed in Winthrop's capacity as a Judge of Probate.

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The diary and commonplace book of Perez Fobes is written on unlined pages in a notebook with a sewn binding at the top of the pages; only the edge of the original leather softcover remain. The volume holds handwritten entries added irregularly from August 23, 1759 until December 1760 while Fobes was a student at Harvard College. The topics range from the irreverent, to the mundane, to the theological and scientific. The notebook serves to chronicle both his daily activities, such as books he read, lectures he attended, and travel, as well as a place to note humorous sayings, transcribe book passages, or ponder religious ideas such as original sin. In the volume, Fobes devotes considerable space to the subject of astronomy, and drew a picture of the "The Solar System Serundum Coper[nici] with the Or[bit] of 5 Remarkable Comets." At the back of the book, on unattached pages is a short personal dictionary for the letters A-K kept by Fobes.

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This layer is a georeferenced raster image of the historic paper map entitled: Map showing the Portland & Rochester railroad and its connections, prepared by G.W. & C.B. Colton & Co. It was published in 1860. Scale [ca. 1:900,000]. Covers Vermont, New Hampshire, Massachusetts, Connecticut, Rhode Island, and portions of New York, Maine, and the provinces of Quebec and New Brunswick, Canada.The image inside the map neatline is georeferenced to the surface of the earth and fit to the USA Contiguous Albers Equal Area Conic projection (Meters). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, or other information associated with the principal map. This map shows features such as railraods, principal and proposed railroad connections, drainage, state, county, and town boundaries, and more. Relief shown by hachures. Includes table of distances and inset: [Northeastern United States]. Scale [ca. 1:7,600,000].This layer is part of a selection of digitally scanned and georeferenced historic maps of New England from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of regions, originators, ground condition dates, scales, and purposes.

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After Russia annexed Crimea in early 2014 and then intervened, manu militari, in the Eastern part of Ukraine, the European Union wanted to show its disapproval and put pressure on Russia to change its behaviour. A wide variety of measures were taken, including the imposition of individual restrictions, such as asset freezes and travel bans, but also the suspension of development loans from the EBRD. But the EU (together with the United States) also took, in July and September 2014, a set of broader measures: limited access to EU primary and secondary capital markets for targeted Russian financial institutions and energy and defence companies; export and import bans on trade in arms; an export ban for dual-use goods and reduction of Russia’s access to sensitive technologies and services linked to oil production.

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"Guide in using plan description and annual report forms prepared by the Secretary of Labor."

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Corporate contributors include: Genesee Pure Food Company; Jell-O-Co. Inc.

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Each vol. has also a distinctive title: 1957- United States participation in international travel.