Hub Location Problem e Site Selection: il caso FAAC Technologies

Questa tesi ha l’obbiettivo di studiare e seguire la creazione un modello matematico che possa risolvere un problema logistico di Hub Facility Location reale, per l’individuazione del posizionamento ottimale di uno o più depositi all’interno di una rete distributiva europea e per l’assegnazione dei rispettivi clienti. Si fa riferimento alla progettazione della rete logistica per rispondere alle necessità del cliente, relativamente ad una domanda multiprodotto. Questo problema è stato studiato a partire da un caso reale aziendale per la valutazione della convenienza nella sostituzione di quattro magazzini locali con uno/due hub logistici che possano servire tutte le aree. Il modello distributivo può anche essere adoperato per valutare l’effetto della variazione, dal punto di vista economico, del servizio di trasporto e di tariffario. La determinazione della posizione ottimale e del numero dei magazzini avviene tramite un modello matematico che considera al proprio interno sia costi fissi relativi alla gestione dei magazzini (quindi costo di stabilimento, personale e giacenza) e sia i costi relativi al trasporto e alla spedizione dei prodotti sulle diverse aree geografiche. In particolare, la formulazione matematica si fonda su un modello Programmazione Lineare Intera, risolto in tempi molto brevi attraverso un software di ottimizzazione, nonostante la grande mole di dati in input del problema. In particolare, si ha lo studio per l’integrazione di tariffari di trasporto diversi e delle economie di scala per dare consistenza ad un modello teorico. Inoltre, per ricercare la migliore soluzione di quelle ottenute sono poi emersi altri fattori oltre a quello economico, ad esempio il tempo di trasporto (transit-time) che è un fattore chiave per ottenere la soddisfazione e la fedeltà del cliente e attitudine dell’area geografica ad accogliere una piattaforma logistica, con un occhio sugli sviluppi futuri.

Linking Real Time and Location in Scheduling Demand-Responsive Transit, September 1996

The role of rural demand-responsive transit is changing, and with that change is coming an increasing need for technology. As long as rural transit was limited to a type of social service transportation for a specific set of clients who primarily traveled in groups to common meal sites, work centers for the disabled, or clinics in larger communities, a preset calendar augmented by notes on a yellow legal pad was sufficient to develop schedules. Any individual trips were arranged at least 24 to 48 hours ahead of time and were carefully scheduled the night before in half-hour or twenty-minute windows by a dispatcher who knew every lane in the service area. Since it took hours to build the schedule, any last-minute changes could wreak havoc with the plans and raise the stress level in the dispatch office. Nevertheless, given these parameters, a manual scheduling system worked for a small demand-responsive operation.

Taunton's citizens' and travelers' rapid transit map and time table of the Metropolitan and New York elevated railways : showing, on a new plan, the railways with up and down-town tracks ... ferries, etc., etc.

Covers Manhattan south of 62nd Street.

Oral and pharyngeal transit of a paste bolus in Chagas` disease

We measured the oral and pharyngeal transit of a paste bolus in 20 patients with Chagas` disease and 21 controls. Each subject swallowed of a 10-ml paste bolus prepared with 50 ml of water and 4.5 g of instant food thickener labeled with 55.5 MBq of 99(m) technetium phytate. After the scintigraphic recording of the transit, we delineated regions of interest (ROI) corresponding to mouth, pharynx, and proximal esophagus. Time-activity curves were generated for each ROI. There was no difference between patients with Chagas` disease and controls with respect to the duration of oral and pharyngeal transit, amount of pharyngeal residue, or flux of bolus entry into the proximal esophagus. The amount of oral residue was higher in patients with Chagas` disease (median = 0.71 ml) than in controls (median = 0.45 ml). The pharyngeal clearance duration was longer in patients with Chagas` disease (median = 0.85 s) than in controls (median = 0.60 s). The oral transit duration of the patients with Chagas` disease and dysphagia (median = 0.55 s, n = 14) was shorter than the oral transit duration of chagasic patients without dysphagia (median = 0.80 s, n = 6). We conclude that when swallowing a paste bolus, patients with Chagas` disease may have an increased amount of oral residue and a longer pharyngeal clearance duration than asymptomatic volunteers.

Simultaneous observations of ionospheric quasiperiodic scintillations from short and long meridional baselines using VHF transmissions from transit satellites

For the first time it was possible to observe regular quasiperiodic scintillations (QPS) in VHF radio-satellite transmissions from orbiting satellites simultaneously at short (2.1 km) and long (121 km) meridional baselines in the vicinity of a typical mid-latitude station (Brisbane; 27.5degreesS and 152.9degreesE geog. and 35.6degrees invar.lat.), using three sites (St. Lucia-S, Taringa-T in Brisbane and Boreen Pt.-B, north of Brisbane). A few pronounced quasiperiodic (QP) events were recorded showing unambiguous regular structures at the sites which made it possible to deduce a time displacement of the regular fading minimum at S, T and B. The QP structure is highly dependent on the geometry of the ray-path from a satellite to the observer which is manifested as a change of a QP event from symmetrical to non-symmetrical for stations separated by 2.1 km, and to a radical change in the structure of the event over a distance of 121 km. It is suggested the short-duration intense QP events are due to a Fresnel diffraction (or a reflection mechanism) of radio-satellite signals by a single ionospheric irregularity in a form of an ellipsoid with a large ionization gradient along the major axis. The structure of a QP event depends on the angle of viewing of the irregular blob from a radio-satellite. In view of this it is suggested that the reported variety of the ionization formation, responsible for different types of QPS, is only apparent but not real. (C) 2003 Elsevier Science Ltd. All rights reserved.

Deploying public surface transit to forward messages in DTN

Delay Tolerant Network (DTN) is a communication architecture enabling connectivity in a topology with unregular end-to-end network connection. DTN enables communication in environments with cross-connectivity, large delays and delivery time variations, and a high error rate. DTN can be used in vehicular networks where public transport get involved. This research aims to analyze the role of public transit as a DTN routing infrastructure. The impact of using public transit as a relay router is investigated by referencing the network performance, defined by its delivery ratio, average delay and overhead. The results show that public transit can be used as a backbone for DTN in an urban scenario using existing protocols. This opens insights for future researches on routing algorithm and protocol design.

Transit Manager's Handbook, September, 2010

This handbook provides an overview of public transit in Iowa and how to do business with the Iowa Department of Transportation (Iowa DOT) Office of Public Transit (OPT). It is intended to be a tool to assist transit managers navigate through the many policies, procedures and requirements of state and federal government. This handbook can be used to provide orientation for new personnel; to help clarify the relationships and required procedures for existing personnel; and to provide easier accessibility to regulations and procedures. Input on the content of the handbook to increase its usefulness is encouraged at any time.

Cedar-Iowa River Rail Transit Project Feasibility Study, November 9, 2006

Five Seasons Transportation & Parking (FSTP) and the Johnson County Council of Governments (JCCOG) are interested in evaluating the feasibility of prospective passenger rail service(s) that would operate over existing trackage of the Cedar Rapids and Iowa City Railway Company (CRANDIC), seen below left, and/or the Iowa Interstate Railroad System (IAIS), seen below right, connecting Cedar Rapids, Iowa City and the Amana Colonies. To perform the study, FSTP and JCCOG selected R.L. Banks & Associates, Inc. (RLBA) as Prime Contractors, HNTB Corporation (HNTB) and Snyder & Associates, Inc. (Snyder) as Subcontractors, hereafter Consultant Team. Both railroads participated in the study and contributed time and resources, as did many local government and civic organizations. The purpose of the study is to determine whether it is feasible to establish regularly scheduled passenger rail service and/or special event excursion rail service, in conjunction with the Five Seasons Transit system, Iowa City Transit, East Central Iowa Transit, Coralville Transit and the University of Iowa CAMBUS.

Evaluation of In-Use Fuel Economy and On-Board Emissions for Hybrid and Regular CyRide Transit Buses, October 2012

The objective of this project was to evaluate the in-use fuel economy and emission differences between hybrid-electric and conventional transit buses for the Ames, Iowa transit authority, CyRide. These CyRide buses were deployed in the fall of 2010. Fuel economy was compared for the hybrid and control buses. Several older bus types were also available and were included in the analysis. Hybrid buses had the highest fuel economy for all time periods for all bus types. Hybrid buses had a fuel economy that was 11.8 percent higher than control buses overall, 12.2 percent higher than buses with model years 2007 and newer, 23.4 percent higher than model years 2004 through 2006, 10.2 percent higher than model years 1998 through 2003, 38.1 percent higher than model years 1994 through 1997, 36.8 percent higher than model years 1991 through 1993, and 36.8 percent higher for model years pre-1991. On-road emissions were also compared for three of the hybrid buses and two control buses using a portable emissions monitor. On-average, carbon dioxide, carbon monoxide, and hybrid carbon emissions were much higher for the control buses than for the hybrid buses. However, on average nitrogen oxide emissions were higher for the hybrid buses.

Personal soundtracks on public transit : personal listening devices and socio-spatial negotiations of students' bus journeys

One way of exploring the power of sound in the experience and constitution of space is through the phenomenon of personal listening devices (PLDs) in public environments. In this thesis, I draw from in-depth interviews with eleven Brock University students in S1. Catharines, Ontario, to show how PLDs (such as MP3 players like the iPod) are used to create personalized soundscapes and mediate their public transit journeys. I discuss how my interview participants experience the space-time of public transit, and show how PLDs are used to mediate these experiences in acoustic and non-acoustic ways. PLD use demonstrates that acoustic and environmental experiences are co-constitutive, which highlights a kinaesthetic quality of the transit-space. My empirical findings show that PLDs transform space, particularly by overlapping public and private appropriations of the bus. I use these empirical findings to discuss the PLD phenomenon in the theoretical context of spatiality, and more specifically, acoustic space. J develop the ontological notion of acoustic space, stating that space shares many of the properties of sound, and argue that sound is a rich epistemological tool for understanding and explaining our everyday experiences.

Décliner la frontière : transit et contagion de la violence dans la fiction sacrificielle de Bernard-Marie Koltès

Ce mémoire de maîtrise traite de quatre pièces de l’auteur français Bernard-Marie Koltès. Résolument axé sur l’étude du texte écrit, il vise dans un premier temps l’analyse d’un ensemble de désajustements et d’une culture de l’équivoque dans le traitement du lieu, du temps et de l’identité. Le premier but de ces analyses est l’approfondissement de certaines avenues déjà investies par la critique (marginalité des lieux et des personnages, présence constante de la violence et de la mort, etc.), dans la recherche d’une signification globale à un ensemble de pratiques textuelles liées à la notion de limite ou de frontière. Opérant un changement de perspective, la seconde partie de l’étude s’attarde à la violence ainsi qu’aux modalités et implications de sa mise en texte dans une étude croisée de l’acte créateur et de la pratique de lecture. À partir de la théorie du sacrifice élaborée par René Girard dans La violence et le sacré, et faisant dialoguer certains textes importants d’auteurs divers (Aristote, Nietzsche, Artaud, Foucault, Derrida et Adorno), l’analyse vise à inscrire la littérarité du texte koltésien dans une entreprise plus vaste ayant à voir avec la violence, sa régulation et sa diffusion. Au carrefour des études théâtrales, de la littérature et de la philosophie, cette réflexion cherche à concevoir le théâtre de Koltès (particulièrement Roberto Zucco) comme un sacrifice rituel, afin de mieux en comprendre le rapport au réel et certaines de ses particularités du point de vue du mécanisme cathartique.

Determinants of Accelerated Small Intestinal Transit in Alcohol-Related Chronic Pancreatitis

Patients with chronic pancreatitis may have abnormal gastrointestinal transit, but the factors underlying these abnormalities are poorly understood. Gastrointestinal transit was assessed, in 40 male outpatients with alcohol-related chronic pancreatitis and 18 controls, by scintigraphy after a liquid meal labeled with (99m)technetium-phytate. Blood and urinary glucose, fecal fat excretion, nutritional status, and cardiovascular autonomic function were determined in all patients. The influence of diabetes mellitus, malabsorption, malnutrition, and autonomic neuropathy on abnormal gastrointestinal transit was assessed by univariate analysis and Bayesian multiple regression analysis. Accelerated gastrointestinal transit was found in 11 patients who showed abnormally rapid arrival of the meal marker to the cecum. Univariate and Bayesian analysis showed that diabetes mellitus and autonomic neuropathy had significant influences on rapid transit, which was not associated with either malabsorption or malnutrition. In conclusion, rapid gastrointestinal transit in patients with alcohol-related chronic pancreatitis is related to diabetes mellitus and autonomic neuropathy.

Employment of a noninvasive magnetic method for evaluation of gastrointestinal transit in rats

AC Biosusceptometry (ACB) was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy. © 2012 Quini et al.; licensee BioMed Central Ltd.

Melhoria do nível de serviço no atendimento ao cliente por meio da estrutura direta de distribuição Transit Point

Increasingly competitive markets have driven the search for companies in many different ways to win and keep customers. The service level is basically the performance of companies in fulfilling the orders made, or how companies demonstrate to their clients efforts in their behalf. This work aims to solve the difficulties faced by a multinational company present in Brazil, in the distribution of its products in the category Ice Cream in order to improve the service level of their customers. Review the logistics network and concepts related to the distribution system of products is one of several ways to achieve this goal, as well as the use of IT and tools to assist in planning and programming of the physical distribution of products. In this study we used the concept of direct distribution system called Transit Point (TP). The TP provides at the same time, a strategy of rapid response, flexibility, low transportation costs and no inventory. A router - software capable of simulating the actual conditions experienced in the daily distribution - was used to assist in calculations. Results showed reductions of up to 47.5% in transportation costs and better conditions were provided in the distribution of products, positively impacting on service levels and in the maintenance of products quality, with a reduction of 1.6% of the total costs involve