Resumo em Inglês:

Abstract The article presents development of a closed-form corridor choice model under hypothetical variable message sign (VMS) based traffic information. A single VMS board is assumed to display traffic information at a junction of two alternative and competitive traffic corridors connecting two catchment areas in Kolkata city, India. The corridor choice models are developed by combining revealed preference (RP) and stated preference (SP) data sources. The development of a combined RP-SP model is a challenging task as different data sources have their respective error terms. In this work, the data sources are combined by exploiting their respective merits; while discarding their respective de-merits. Here a procedure of developing composite utility function is presented, which is constituted of estimates of attributes from SP data source and alternative specific constant term of alternatives calibrated from RP data source, while fixing all coefficients of attributes at SP estimates. The construction of corridor choice models is demonstrated for two types of VMS based traffic information, which differs in terms of the content displayed on VMS board and also for two types of trip maker- namely private car and taxi. Under the influence of VMS-based traffic information, trip makers are found to take corridor choice decision based on the rational trade-off between travel time information and direct travel cost of alternative traffic corridors. The alternative-specific-constant term of choice models indicates that in presence of VMS-based information, private car trip makers are likely to be less biased to choose comparatively longer but almost free-flow traffic corridor (thereby less travel time corridor); while taxi trip makers are likely to be more biased to choose longer but almost free-flow traffic corridor to arrive at their destination.

Resumo em Inglês:

Abstract Predictive models for entry flow at rotary intersections in Akure - a developing city in Nigeria- have been developed. Data were collected at the intersections critical to traffic flow in the study area using a cine camera placed at a vantage point from the road sections during peak and off-peak periods in week days. Entry flow (qe) was modelled as a function of circulating flow (qc), delay (da), headway (h) and geometric features of the intersections. The data were fitted to a multiple linear regression equation to obtain the generalized flow models for peak and off peak periods. The equations obtained were validated using empirical data other than those used to calibrate the model. The adjusted R2 values obtained during the peak and off peak periods were 95.8% and 87.7% respectively, indicating that the independent variables (circulating flow, delay and headway) made significant contributions in predicting the entry flow. The models developed can be used to evaluate entry flow at rotary intersections in the study area and other cities in developing countries with similar traffic characteristics for which such models are scarce, thereby facilitating planning and design of effective traffic control mechanisms.

Resumo em Inglês:

Abstract Road accident fatalities have been on an increasing trend for the last decade or so in India. Hence traffic safety management has emerged as a topic of discussion for researchers all over the world. Hence accident modelling on different factors causing them has to be conducted. Accident modelling helps us to know the real causative agents behind an accident to occur. The effect of one cause can be greater than the other. And those causes can only be known from accident modelling. In this paper we have tried to divide this accident modelling techniques into two different categories based on the location of road i.e. accidents on urban roads and on rural roads. In both urban and rural road accident studies it was seen that mainly regression techniques like linear, multi-linear, logit and poisons regression have been used for modelling the road crashes. It was also marked that mostly authors have tried to research on one cause and go deep into it rather considering all factors at a time. From the studies it was found that speed and age along with gender has been the area of study for accident causes in urban areas whereas in rural roads mostly all authors have limited their studies to speed on roads and has been noted as the major cause of accidents in rural areas. This paper has tried to review as much papers as possible and various gaps in research along with future scope of study in this area has been indicated. Starting from the basic models like negative binomial/Poisson's model to the logistic and linear regressions to the new modeling techniques involving genetic mining and fuzzy logics have been discussed explicitly in the paper.

Resumo em Português:

Resumo O objetivo desse artigo é desenvolver um modelo empírico de demanda por viagens de um aeroporto recentemente privatizado pelo governo federal: o Aeroporto Internacional de Confins -Tancredo Neves, em Belo Horizonte. As estimativas da modelagem sugerem que o futuro da concessão do aeroporto está bastante atrelado ao futuro do crescimento econômico do País: com uso de dados setoriais e modelo econométrico com uso de variáveis instrumentais, foi possível estimar elasticidades PIB e preço da demanda em torno de 2 e -0,15, respectivamente. A robustez das estimativas obtidas foi checada por meio de um conjunto de análises de sensibilidade com uso de estimadores alternativos. Como conclusão temos que, se por um lado, um baixo crescimento da economia pode afetar negativamente o retorno esperado da concessão dada a alta elasticidade-PIB da demanda aeroportuária, por outro lado, a baixa elasticidadepreço pode gerar pressões dos entes regulados por realinhamentos tarifários que mantenham o equilíbrio econômico-financeiro e a rentabilidade do operador.

Resumo em Inglês:

Abstract The purpose of this paper is to develop an empirical model of demand for travel to the airport recently privatized by the federal government: the Confins-Tancredo Neves International Airport, Belo Horizonte, Brazil. Estimates of the modelling suggest that the future of the airport concession is considerably related to the economic growth of the country: with the use of industry data and econometric model of instrumental variables, it was possible to estimate GDP and price elasticities of demand around 2 and -0.15, respectively. The robustness of the estimates was checked by means of a set of sensitivity analyses using alternative estimators. In conclusion, we have, on one hand, a low growth economy may negatively affect the expected return of the concession given to high GDP elasticity of demand of airport, on the other hand, the low price elasticity may generate pressures from the regulated entities for tariff increases that maintain economic and financial stability and profitability of the operator.

Resumo em Inglês:

Abstract This study evaluates airline customer loyalty and estimates the switching costs for a domestic airline route in Brazil through a stated preference survey. Several structures of discrete choice models were tested to represent the choice of behavior: multinomial logit, mixed logit random coefficients, multinomial logit incorporating systematic variations of preferences, mixed logit error component and mixed logit error component incorporating systematic variations of preferences. The results showed that loyal passengers are more likely to choose the dominant Brazilian airline Tam. The switching costs of passengers loyal to Tam, for this sample, are equivalent to 15% of the fare, which represents much more than the percentage for other companies. These passengers are less sensitive to variations in the fares and incur higher costs not to switch airlines.

Resumo em Inglês:

Abstract Managing the increasing traffic is a big problem all over the world. Intelligent Transportation System (ITS) provides solution to these problems with the help of new technologies. ITS is an integrated system that implements a broad range of communication, control, vehicle sensing and electronics technologies to solve and manage the traffic problems. ITS is being used in the developed countries since past two decades, but it is still a new concept when developing countries like India, Brazil, China, South Africa etc. are concerned. In the present study we have studied four major parts of the ITS i.e., Advanced Traveler Information System (ATIS), Advanced Traffic Management System (ATMS), Advanced Public Transportation System (APTS), and Emergency Management System (EMS). Objective of the paper is to study various ITS architecture and model and review such models to get in-depth of their architecture. Hence architecture and developed models over the years of four major branches of ITS have been reviewed here to make a comparison analysis of different models that have been developed by the researchers in their studies. It will lead to the gaps in the knowledge which can be further studied. The paper highlights the conclusions extracted from the studies of different systems and also gives the future scope in the field of ITS to make it more user friendly and accessible.

Resumo em Inglês:

Abstract Expansion analyses are performed on a bus transit network in the City of Laramie area in Wyoming. Expansion analysis is based on the needs identified by the bus transportation agency and the community. This paper examines the expansions, operations and sustainability of a bus transit in a small city having a population of 30,000 people. When funding is limited, it is very important to identify the best route that provides the services to the more people. Gravity model and ArcGIS software have been used to analyze the data. This paper examines the background of the transportation agency and existing services, finally develops a bus routing model for identifying future expansions. This research identified that one of the existing bus stops account for 1% of the ridership which can be closed. This research also found that adding a new loop considering same number of buses would increase the ridership significantly without increasing headway.

Resumo em Inglês:

Abstract Space syntax researchers have found that the role of roadway configuration itself is apparent in influencing urban movement. Despite this important finding, conventional traffic-assignment models are not seen to take the configurational measures into account for modeling urban movement networks. The argument is where exactly is the short fall in understanding the influence of roadway configuration on the urban phenomena of trip-making and route choice from the conventional traffic-assignment stance? This paper throws deeper insights into this question and reports the progress in the area of transportation planning research by producing theoretical evidence showing that configurational influence on urban movement gets captured through the capacity-restrained-analysis model-one of the prevalent trafficassignment models adopted by the transportation planning community. The conclusion reinforces the syntax research finding explaining that topological complexities of urban textures significantly get involved in modeling urban movement networks much of which has not been addressed before in the conventional traffic-assignment models.

Resumo em Inglês:

Abstract Nowadays, there are Concrete Pavements (CPs) with Joints Configurations (JCs) that reduce initial costs about 20%. But are these JCs produced by Early-Entry Saw-Cutting (EESC), Unsealed Joints (UJs) and Shorter Joint Spacing (ShJS) able to maintain the traditional performance of CPs? The aim of this paper is to analyze the effects of the joints behaviour (JB) on the performance of CPs with these JCs. The JB is characterized by joints activation, opening, deterioration and Load Transfer Efficiency (LTE), not in an isolated but in a comprehensive way to determine not only the complete JB, but their effects on the CPs performance, so upon the users. The paper contributes not only with a comprehensive analysis of the innovative JCs, but also with new field experiences, that allow concluding the JCs can maintain or even improve the traditional performance of CPs if the saw-cutting depth ≥ 30% to assure 100% joints activation, joints opening < 1.2 mm, so LTE ≥ 70%. UJs with thin blade (< 3 mm) and limited fines in the base can be used in CPs applications as streets, low volume roads, parking lots, bus corridors (moderate rainfall) and any CP where the seals do not work well.

Resumo em Inglês:

Abstract Despite the potential of agriculture in Nigeria, transport infrastructure projects in Nigeria have been adversely affected by poor policy formulation. This paper presents transportation infrastructure management within the past years in Nigeria and identifies that poor integration and management of the transportation sector with other productive sectors of the economy. For example from 2009 to 2011 budgets, the transport sector had the lowest allocation which was approximately 10 billion naira while other sectors—Education, Power; Works and Housing, and Urban Development had 60 billion, 18 billion and 35 billion naira respectively. Despite the low allocation on the average, transport had the highest budget-performance index of 37.29%, and therefore the highest performance rate. Research on transportation infrastructure development in Nigeria is not new, however; understanding transportation integration and management with other productive sectors of Nigerian economy is still under-researched. Data on transportation and agriculture investment are not readily available despite its importance in national development. Integration between state and federal governments' activities was recommended to identify the resource areas within the state to make policies that would enhance the income of both the state and those involved in fiscal generation.

Resumo em Português:

Abstract O problema de programação de caminhões é um tema de grande relevância na gestão de frota das empresas. Estas enfrentam dificuldades em gerenciar seus veículos devido às diversas variáveis inerentes ao processo, tais como o tamanho ideal da frota, os diversos tipos de caminhões disponíveis, a capacidade de carga do caminhão, as informações técnicas do cliente e o agendamento das viagens. No que se refere ao transporte de derivados de petróleo, existem diversas características operacionais que dificultam a programação de caminhões. O presente trabalho tem como objetivo desenvolver um modelo de programação inteira para a otimização da programação de veículos de múltiplos tipos para o transporte de derivados de petróleo para obras de construção de rodovias. Foi desenvolvido um modelo que buscasse a minimização da frota de caminhões disponíveis. Como conclusões, pode-se ressaltar que a metodologia empregada serviu para minimizar em 23,3%, em media, a frota necessária no período analisado. O desenvolvimento de indicadores de desempenho permitiu avaliar a qualidade das soluções geradas.

Resumo em Inglês:

Abstract The truck scheduling problem is an important topic in the companies' fleet management. Many companies face difficulties to manage their vehicles due to several variables inherent to the management process, such as the optimal fleet size, multiple types of trucks available, trucks capacity, the technical information from the client's construction site and trips scheduling. In terms of the transportation of oil products, there are many operational characteristics that make the truck scheduling difficult. The purpose of this research study was to develop an Integer Programming model to optimize the multi-type truck scheduling for the transportation of oil products for road construction sites. A model that aimed to minimize the truck fleet available was developed. The method used has minimized the available fleet in 23,3%, in average, in the period under review. The development of key performance indicators allows to evaluate the quality of the solutions created.