Real-time Intraday Traffic Volume Forecasting – A Hybrid Application Using Singular Spectrum Analysis and Artificial Neural Networks

The present paper provides a comparative evaluation of hybrid Singular Spectrum Analysis (SSA) and Artificial Neural Networks (ANN) against conventional ANN, applied on real time intraday traffic volume forecasting. The main research objective was to assess the applicability and functionality of intraday traffic volume forecasting, based on toll station measurements. The proposed methodology was implemented and evaluated upon a custom developed forecasting software toolbox, based on the software Mathworks MatLab, by using real data from Iasmos-Greece toll station. Experimental results demonstrated a superior ex post forecasting accuracy of the proposed hybrid forecasting methodology against conventional ANN, when compared to performance of usual statistical criteria (Mean Absolute Error, Mean Squared Error, Root Mean Squared Error, Coefficient of Determination R2, Theil's inequality coefficient). The obtained results revealed that the hybrid model could advance forecasting accuracy of a conventional ANN model in intraday traffic volume forecasting, while embedding hybrid forecasting algorithm in an Intelligent Transport System could provide an advanced decision support module for transportation system maintenance, operation and management

Exploring the Factors Influencing Parental Choices on School Trips

Within the last decades, the examination and definition of factors affecting the mode choice decision on school trips has gained much of attention, as the completion of such trips represent a vast percentage of total travel demand. Key players of the decision process are students' parents, deciding how their children will complete everyday trips from their residence to the school unit and vice versa. The current study examines the factors affecting parents' travel mode choice for school trips of both primary and high school students in Thessaloniki city, Greece. Data collected is based on a questionnaire survey in which, 512 parents participated, stating their perception regarding the use of several transport modes for school trips and the motives behind specific adopted travel behavioural aspects. Three main topics are examined and analysed related to the parents' attitudes and their travel habits in the choice of motorized and non-motorized transport modes, the parents' perception regarding the built environment safety, and the parents' perception regarding specific parameters which appear to motivate them in the mode choice decision process. For the research analysis, a number of statistical methods and techniques are deployed, starting with descriptive statistical and Pearson's correlation analysis and proceeding with the exploratory and confirmatory factor analysis. The results verify initial thoughts for critical factors which appear to affect parents' choices regarding their children’s school trips while they also gives an initial picture of parents' experiences regarding the school travel mode choice, in an urban environment of a typical Greek city

Environmental Effects and Externalities from the Transport Sector and Sustainable Transportation Planning – A Review

A literature review of the environmental effects and externalities of the transport sector and the concerns in sustainable transport planning is presented in this paper. The relation between air pollution and transport, considering that transport is an important air pollution emitter, is initially analyzed. The causal relationship between per capita GDP and individual consumption for transport, annual growth of global GDP and CO2 emissions and changes in CO2 emissions from fuel combustion by the various transport modes is then explained. Furthermore, energy consumption of transport modes for the EU countries is illustrated, as well as the relation between traffic flow and noise emissions and the implications of transport infrastructure to the landscape and environmental aesthetics. The increase in passenger mobility has caused traffic congestion, constituting an effect which is also quantified. Furthermore, the impact of accidents in terms of injuries, impairments and fatalities is a global social and public health issue. Moreover, the transport policies and the impact on economic and urban development, health, environmental protection and energy, focusing also on possible conflicts and convergence between safety and environmental policies are discussed. Finally, transport sector externalities, quantification in monetary units and possible effects of eventual internalization of these external costs are presented. Keywords: Environmental effects; Externalities; Internalization; Sustainable; Transportation planning JEL Classifications: H23; O44; Q53; R4

Coupling and Decoupling Relationships between Energy Consumption and Air Pollution from the Transport Sector and the Economic Activity

In the present paper an analysis of whether and under which conditions coupling or decoupling exists between growth rates (as reflecting in GDP rates) of the economy and energy consumption and air pollution from the transport sector. An extensive time period from 1995 to 2012 is surveyed and divided into two periods, from 1995 to 2008 (growth period) and from 2008 to 2012 (recession period). The analysis is conducted for the 28 European Union countries and illustrates, for most of these countries, a coupling phenomenon for the growth period and a decoupling phenomenon for the recession period. This finding may be essential for the further institutional steps to be undertaken, in view of the reduction of CO2 and of energy conservation. Keywords: Coupling; Decoupling; Transportation; Environment; Sustainability JEL Classifications: H23; O44; R4; Q53

Analytical model for predicting the buckling load of continuous welded rail tracks

The use of continuous welded rail (CWR) track has solved many of the problems associated with tread surface discontinuities that occur in jointed tracks. However, due to the longitudinal expansion of the rails in CWR tracks being highly constrained, the generated compressive stresses in the rails can cause track buckling in the horizontal plane. Track buckling is a complex phenomenon, in which many factors are involved and around which there is much uncertainty. The objective of this paper is to present an analytical model that can be used to calculate the buckling load of a CWR track. This model accounts for the contributions of base, crib and shoulder ballast and includes the effect of vertical loading on each of these components. Moreover, a parametric study based on this model is developed, in order to understand how and the extent to which the considered factors affect track stability. The results of the study indicate that the characteristics of the existing misalignments in the track are the critical parameters involved in the phenomenon. In addition, maintenance operations that affect the ballast, such as tamping or surfacing, and the dimensions and material of the track sleepers are also important factors.Navarro Martinez, JI.; Villalba Sanchis, I.; Martínez Fernández, P.; Insa Franco, R. (2015). Analytical model for predicting the buckling load of continuous welded rail tracks. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit. 229(5):542-552. doi:10.1177/0954409713518039S5425522295Kerr, A. D. (1978). Analysis of thermal track buckling in the lateral plane. Acta Mechanica, 30(1-2), 17-50. doi:10.1007/bf01177436Grissom, G. T., & Kerr, A. D. (2006). Analysis of lateral track buckling using new frame-type equations. International Journal of Mechanical Sciences, 48(1), 21-32. doi:10.1016/j.ijmecsci.2005.09.006Le Pen, L. M., & Powrie, W. (2011). Contribution of Base, Crib, and Shoulder Ballast to the Lateral Sliding Resistance of Railway Track: A Geotechnical Perspective. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 225(2), 113-128. doi:10.1177/095440971039709

Decoupling of economic growth and emissions in China’s cities: A case study of the Central Plains urban agglomeration

Recently, the economy has grown rapidly in China’s Central Plains urban agglomeration, with high energy consumption and a huge pressure on reducing CO2 emissions. Thus, low-carbon development is an important measure to solve economic, energy and environmental problems. To analyse low-emission development, this paper clarifies the evolutionary characteristics of CO2 emissions and the decoupling relationship between GDP and CO2 emissions based on the latest available data from 2000 to 2015. The results indicate that CO2 emissions of Pingdingshan and Changzhi are higher in the same year. The ratios from coal consumption accounting for the total CO2 emissions are clearly bigger than from other energy types and industrial processes. Changzhi, Luoyang and Pingdingshan have reached their peaks. Five cities have experienced strong decoupling after 2010, 13 cities present weak decoupling, 4 cities present growth connection, and 7 cities show growth negative decoupling. It can be concluded that a relatively smaller proportion of industry and strict policy implementations of coal reduction are the main factors in inhibiting the decoupling. So the proportion of coal purification should be increased firstly. Then, the energy consumption structure should be changed from the traditional coal consumption structure to coal, oil and gas. Lastly, economic means can be used to control CO2 emissions