933 resultados para MASS TRANSIT SYSTEM


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The goal of this research was to evaluate the needs of the intercity common carrier bus service in Iowa. Within the framework of the overall goal, the objectives were to: (1) Examine the detailed operating cost and revenue data of the intercity carriers in Iowa; (2) Develop a model or models to estimate demand in cities and corridors served by the bus industry; (3) Develop a cost function model for estimating a carrier's operating costs; (4) Establish the criteria to be used in assessing the need for changes in bus service; (5) Outline the procedures for estimating route operating costs and revenues and develop a matrix of community and social factors to be considered in evaluation; and (6) Present a case study to demonstrate the methodology. The results of the research are presented in the following chapters: (1) Introduction; (2) Intercity Bus Research and Development; (3) Operating Characteristics of Intercity Carriers in Iowa; (4) Commuter Carriers; (5) Passenger and Revenue Forecasting Models; (6) Operating Cost Relationships; (7) Social and General Welfare Aspects of Intercity Bus Service; (8) Case Study Analysis; and (9) Additional Service Considerations and Recommendations.

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A Job Access project focuses on implementing new or expanded transportation services, targeted at filling transportation gaps and designed to transport welfare recipients and low-income individuals to and from jobs and other employment-related activities such as child care or training.

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The Revised Iowa Energy Conservation Plan: 1979-1980 is a blue print for the state's continued participation. The original Plan contained descriptions of more than 70 programs underway or conceived for state implementation with federal dollars. The Revised Plan contains only those programs to be funded in Federal dollars. The projects include five mandatory programs identified by DOE and several projects selected for funding by the Iowa Energy Policy Council (EPC), the policy making board which governs the state energy agency. The 18-member Council selected the conservation programs at its March 20-21, 1979 meeting. The Council retains the right to amend both the Plan and the budget at any time for the duration of the three-year program.

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The urban mobility has in the bicycle its symbol of the most environmentally sustainable modal of transportation of the planet, title conferred by the United Nations Organization (ONU). Nevertheless, the cities suffer with the traffic jam caused by the automobile fleet growth, what implies in a larger displacement time, injuries to the environment, to financials and to the quality of life. In order to build in a sustainable way the urban mobility, public policies are necessary to encourage the preferential usage, by the society, of the mass transit or the non-motorized type of transportation. Objecting cooperate with the public power and the civil society, this study intents to, through an analysis about the UFPR Extension Program - CICLOVIDA, propose a sustainable urban mobility public policy development, with emphasis in the bicycle´s usage. eferentially, it is discussed concepts such as Society, State and Government as well as public policies, which go in cycles to the State´s and Government´s responsibilities; and are presented the Sustainable Urban Mobility Public Policies (PPMUS) in Brazil. Also, it is debated about the transport by bicycle as an option to the sustainable mobility. Methodologically, the study is of an empiric-social nature, with the application of both qualitative and observational methods, what characterizes as an exploratory level of research, with the researcher´s involvement in the participant form, due to her acting on the Program. Regarding the research lineation, it was used the bibliographic and documental form as well as case study, by means of the nonparametric sampling by accessibility or convenience. Related to the data collection technique, it was used structured interviews with self-applied questionnaires and natural participant observation. Aligned with the research´s objective and matter, the outcome confirmed that the Extension Program CICLOVIDA of the Federal University of Paraná (UFPR) may effectively contribute in the development of a PPMUS proposal with emphasis in the bicycle usage. Thus, it was built a political proposal with a free form writing, objecting subsidize policies both institutional as public MUS through the bicycle usage and therefore, support the mobility, also contributing to the sustainability and to the public development planning.

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OBJECTIVES AND STUDY METHOD: There are two subjects in this thesis: “Lot production size for a parallel machine scheduling problem with auxiliary equipment” and “Bus holding for a simulated traffic network”. Although these two themes seem unrelated, the main idea is the optimization of complex systems. The “Lot production size for a parallel machine scheduling problem with auxiliary equipment” deals with a manufacturing setting where sets of pieces form finished products. The aim is to maximize the profit of the finished products. Each piece may be processed in more than one mold. Molds must be mounted on machines with their corresponding installation setup times. The key point of our methodology is to solve the single period lot-sizing decisions for the finished products together with the piece-mold and the mold-machine assignments, relaxing the constraint that a single mold may not be used in two machines at the same time. For the “Bus holding for a simulated traffic network” we deal with One of the most annoying problems in urban bus operations is bus bunching, which happens when two or more buses arrive at a stop nose to tail. Bus bunching reflects an unreliable service that affects transit operations by increasing passenger-waiting times. This work proposes a linear mathematical programming model that establishes bus holding times at certain stops along a transit corridor to avoid bus bunching. Our approach needs real-time input, so we simulate a transit corridor and apply our mathematical model to the data generated. Thus, the inherent variability of a transit system is considered by the simulation, while the optimization model takes into account the key variables and constraints of the bus operation. CONTRIBUTIONS AND CONCLUSIONS: For the “Lot production size for a parallel machine scheduling problem with auxiliary equipment” the relaxation we propose able to find solutions more efficiently, moreover our experimental results show that most of the solutions verify that molds are non-overlapping even if they are installed on several machines. We propose an exact integer linear programming, a Relax&Fix heuristic, and a multistart greedy algorithm to solve this problem. Experimental results on instances based on real-world data show the efficiency of our approaches. The mathematical model and the algorithm for the lot production size problem, showed in this research, can be used for production planners to help in the scheduling of the manufacturing. For the “Bus holding for a simulated traffic network” most of the literature considers quadratic models that minimize passenger-waiting times, but they are harder to solve and therefore difficult to operate by real-time systems. On the other hand, our methodology reduces passenger-waiting times efficiently given our linear programming model, with the characteristic of applying control intervals just every 5 minutes.

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High speed rail (also commonly known as HSR) is highly regarded as one of the most significant innovation for mass passenger transportation to travellers willing to pay for reduced travel impediments (shorter travel time, convenience, safety, security, comfort, reliability, flexibility, uniqueness and attractiveness). The transport policy in Australia has until now focused primarily on private passenger car transport and air transportation to the degree that State and Federal Governments’ commitments and actions of rail-oriented mass transportation system still remains sketchy in spite of occasional political and public attentions into it. This has resulted in a limited use of passenger rail as a regional transport system. Using one of the several alternative HSR alignments proposed for the South-Eastern Coast of Australia connecting Melbourne, Canberra, Sydney and Brisbane, this study assesses the regional accessibility impacts of Australian HSR system by means of four indicators: location accessibility, economic potential accessibility, daily accessibility and commuting accessibility. These indicators are commonly used in transport geography literature and they offer different concepts of changes in regional accessibility conditions due to a long distance transport system. The results provide an understanding of differential effects on regional accessibility based on the geographical location and size of urban areas along HSR corridor.

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Montréal parle de disposer d’un service rapide par bus depuis une dizaine années. En 2015, les travaux pour réaliser le premier tronçon du projet appelé le SRB Pie-IX commencent à peine. Comment justifier des délais de réalisation de plusieurs années alors que d’autres villes y arrivent en moins de 3 ans? Plusieurs élus et organismes de Montréal dénoncent une problématique de gouvernance du transport collectif. Seulement, il n’est pas évident de saisir la signification de ce concept si souvent invoqué pour justifier, entre autres, les difficultés de la métropole à faire naître des projets métropolitains de transport collectif. Certains évoquent la responsabilité du gouvernement, d’autres avancent la mauvaise répartition des rôles et responsabilités ou encore déplorent le trop grand nombre d’intervenants dans la région métropolitaine. La gouvernance est un concept à la fois flou et complexe qui cherche à établir la bonne conduite des affaires publiques comme celle de la gestion métropolitaine du transport collectif. Cependant, le système de transport collectif fait intervenir une multitude de parties prenantes aux intérêts contradictoires. La « bonne gouvernance » serait d’établir une collaboration fructueuse qui dépasse les limites institutionnalisées des intervenants pour réaliser des projets d’envergure métropolitaine, comme le SRB Pie-IX.

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Montréal parle de disposer d’un service rapide par bus depuis une dizaine années. En 2015, les travaux pour réaliser le premier tronçon du projet appelé le SRB Pie-IX commencent à peine. Comment justifier des délais de réalisation de plusieurs années alors que d’autres villes y arrivent en moins de 3 ans? Plusieurs élus et organismes de Montréal dénoncent une problématique de gouvernance du transport collectif. Seulement, il n’est pas évident de saisir la signification de ce concept si souvent invoqué pour justifier, entre autres, les difficultés de la métropole à faire naître des projets métropolitains de transport collectif. Certains évoquent la responsabilité du gouvernement, d’autres avancent la mauvaise répartition des rôles et responsabilités ou encore déplorent le trop grand nombre d’intervenants dans la région métropolitaine. La gouvernance est un concept à la fois flou et complexe qui cherche à établir la bonne conduite des affaires publiques comme celle de la gestion métropolitaine du transport collectif. Cependant, le système de transport collectif fait intervenir une multitude de parties prenantes aux intérêts contradictoires. La « bonne gouvernance » serait d’établir une collaboration fructueuse qui dépasse les limites institutionnalisées des intervenants pour réaliser des projets d’envergure métropolitaine, comme le SRB Pie-IX.

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Introducción: La rápida detección e identificación bacteriana es fundamental para el manejo de los pacientes críticos que presentan una patología infecciosa, esto requiere de métodos rápidos para el inicio de un correcto tratamiento. En Colombia se usan pruebas microbiología convencional. No hay estudios de espectrofotometría de masas en análisis de muestras de pacientes críticos en Colombia. Objetivo general: Describir la experiencia del análisis microbiológico mediante la tecnología MALDI-TOF MS en muestras tomadas en la Fundación Santa Fe de Bogotá. Materiales y Métodos: Entre junio y julio de 2013, se analizaron 147 aislamientos bacterianos de muestras clínicas, las cuales fueron procesadas previamente por medio del sistema VITEK II. Los aislamientos correspondieron a 88 hemocultivos (60%), 28 urocultivos (19%), y otros cultivos 31 (21%). Resultados: Se obtuvieron 147 aislamientos con identificación adecuada a nivel de género y/o especie así: en el 88.4% (130 muestras) a nivel de género y especie, con una concordancia del 100% comparado con el sistema VITEK II. El porcentaje de identificación fue de 66% en el grupo de bacilos gram negativos no fermentadores, 96% en enterobacterias, 100% en gérmenes fastidiosos, 92% en cocos gram positivos, 100% bacilos gram negativos móviles y 100% en levaduras. No se encontró ninguna concordancia en bacilos gram positivos y gérmenes del genero Aggregatibacter. Conclusiones: El MALDI-TOF es una prueba rápida para la identificación microbiológica de género y especie que concuerda con los resultados obtenidos de manera convencional. Faltan estudios para hacer del MALDI-TOF MS la prueba oro en identificación de gérmenes.

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We present nine newly observed transits of TrES-3, taken as part of a transit timing program using the RISE instrument on the Liverpool Telescope. A Markov-Chain Monte Carlo analysis was used to determine the planet star radius ratio and inclination of the system, which were found to be R-p/R-star = 0.1664(-0.0018)(+0.0011) and i = 81.73(-0.04)(+0.13), respectively, consistent with previous results. The central transit times and uncertainties were also calculated, using a residual-permutation algorithm as an independent check on the errors. A re-analysis of eight previously published TrES-3 light curves was conducted to determine the transit times and uncertainties using consistent techniques. Whilst the transit times were not found to be in agreement with a linear ephemeris, giving chi(2) = 35.07 for 15 degrees of freedom, we interpret this to be the result of systematics in the light curves rather than a real transit timing variation. This is because the light curves that show the largest deviation from a constant period either have relatively little out-of-transit coverage or have clear systematics. A new ephemeris was calculated using the transit times and was found to be T-c(0) = 2454632.62610 +/- 0.00006 HJD and P = 1.3061864 +/- 0.0000005 days. The transit times were then used to place upper mass limits as a function of the period ratio of a potential perturbing planet, showing that our data are sufficiently sensitive to have probed sub-Earth mass planets in both interior and exterior 2:1 resonances, assuming that the additional planet is in an initially circular orbit.

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We present seven light curves of the exoplanet system HAT-P-3, taken as part of a transit timing programme using the rapid imager to search for exoplanets instrument on the Liverpool Telescope. The light curves are analysed using a Markov chain Monte Carlo algorithm to update the parameters of the system. The inclination is found to be i = 86.75+0.22-0.21°, the planet-star radius ratio to be Rp/R* = 0.1098+0.0010-0.0012 and the stellar radius to be R* = 0.834+0.018-0.026Rsolar, consistent with previous results but with a significant improvement in the precision. Central transit times and uncertainties for each light curve are also determined, and a residual permutation algorithm is used as an independent check on the errors. The transit times are found to be consistent with a linear ephemeris, and a new ephemeris is calculated as Tc(0) = 2454856.70118 +/- 0.00018 HJD and P = 2.899738 +/- 0.000007 d. Model timing residuals are fitted to the measured timing residuals to place upper mass limits for a hypothetical perturbing planet as a function of the period ratio. These show that we have probed for planets with masses as low as 0.33 and 1.81 M? in the interior and exterior 2:1 resonances, respectively, assuming the planets are initially in circular orbits.

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We report the discovery of WASP-34b, a sub-Jupiter-mass exoplanet transiting its 10.4-magnitude solar-type host star (1SWASP J110135.89-235138.4; TYC 6636-540-1) every 4.3177 days in a slightly eccentric orbit (e = 0.038±0.012). We find a planetary mass of 0.59±0.01 MJup and radius of 1.22-0.08+0.11 RJup. There is a linear trend in the radial velocities of 55±4 m s-1 y-1 indicating the presence of a long-period third body in the system with a mass ?0.45 MJup at a distance of ?1.2 AU from the host star. This third-body is either a low-mass star, a white dwarf, or another planet. The transit depth ((RP/Rstar)2 = 0.0126) and high impact parameter (b = 0.90) suggest that this could be the first known transiting exoplanet expected to undergo grazing transits, but with a confidence of only 80%. Radial velocity and photometric data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/526/A130

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Drug delivery systems based on natural polysaccharides, such as chitosan (CS) and pectin (PC), rather than on synthetic polymers, have been widely studied. Some reasons for that are low toxicity and costs and high biodegradability of the formers. A multiparticulate system based on CS and PC was developed in our laboratories, including the addition of an enteric polymer, cellulose acetate phtalate (CAP). Such improvement promoted stronger gastric and enteric resistances, as assessed in vitro, making the systems more selective to enzymatic degradation in the colon. Although in vitro dissolution tests can simulate some properties concerning the gastrointestinal transit (GT), collaborating to characterize the systems behavior in the biological fluids, frequently they do not result in satisfactory in vitro/in vivo correlations. The objective of this work was to follow in vivo the GT of the particles developed by means of AC biosusceptometry (ACB), a non-invasive and of low cost methodology. The particles containing ferrite in powder form were prepared by complex coacervation using an ideal 3:1:1 mass ratio for PC:CS:CAP. The magnetic particles were administered to healthy volunteers by oral route. The GT was monitored by using multi-sensor ACB system and the signal acquisition was performed every IS min until the colonic region was reached. By means of ACB technique, it was possible to acquiring images generated by the magnetic particles within the whole gastrointestinal tract including the colonic region. Variable particles transit times were observed among the volunteers, but without interference on the mapping of the particles until the colonic region. The particles were able to produce magnetic field strong enough to generate signals adequate for mapping the particles. The results suggest that integral particles reached the colon, after they resisted against gastric and enteric media. Studies associating transit time and in vivo drug release are in development in order to confirm the efficiency of the systems.

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Context. Planet formation models have been developed during the past years to try to reproduce what has been observed of both the solar system and the extrasolar planets. Some of these models have partially succeeded, but they focus on massive planets and, for the sake of simplicity, exclude planets belonging to planetary systems. However, more and more planets are now found in planetary systems. This tendency, which is a result of radial velocity, transit, and direct imaging surveys, seems to be even more pronounced for low-mass planets. These new observations require improving planet formation models, including new physics, and considering the formation of systems. Aims: In a recent series of papers, we have presented some improvements in the physics of our models, focussing in particular on the internal structure of forming planets, and on the computation of the excitation state of planetesimals and their resulting accretion rate. In this paper, we focus on the concurrent effect of the formation of more than one planet in the same protoplanetary disc and show the effect, in terms of architecture and composition of this multiplicity. Methods: We used an N-body calculation including collision detection to compute the orbital evolution of a planetary system. Moreover, we describe the effect of competition for accretion of gas and solids, as well as the effect of gravitational interactions between planets. Results: We show that the masses and semi-major axes of planets are modified by both the effect of competition and gravitational interactions. We also present the effect of the assumed number of forming planets in the same system (a free parameter of the model), as well as the effect of the inclination and eccentricity damping. We find that the fraction of ejected planets increases from nearly 0 to 8% as we change the number of embryos we seed the system with from 2 to 20 planetary embryos. Moreover, our calculations show that, when considering planets more massive than ~5 M⊕, simulations with 10 or 20 planetary embryos statistically give the same results in terms of mass function and period distribution.

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Dwell times at stations and inter-station run times are the two major operational parameters to maintain train schedule in railway service. Current practices on dwell-time and run-time control are that they are only optimal with respect to certain nominal traffic conditions, but not necessarily the current service demand. The advantages of dwell-time and run-time control on trains are therefore not fully considered. The application of a dynamic programming approach, with the aid of an event-based model, to devise an optimal set of dwell times and run times for trains under given operational constraints over a regional level is presented. Since train operation is interactive and of multi-attributes, dwell-time and run-time coordination among trains is a multi-dimensional problem. The computational demand on devising trains' instructions, a prime concern in real-time applications, is excessively high. To properly reduce the computational demand in the provision of appropriate dwell times and run times for trains, a DC railway line is divided into a number of regions and each region is controlled by a dwell- time and run-time controller. The performance and feasibility of the controller in formulating the dwell-time and run-time solutions for real-time applications are demonstrated through simulations.