Interval type-2 fuzzy sets improved by Simulated Annealing for locating the electric charging stations

Electric vehicles are the key to facilitating the transition to low-carbon ‘green’ transport. However, there are concerns with their range and the location of the charging stations which delay a full-fledged adoption of their use. Hence, the electric charging infrastructure in a given region is critical to mitigating those concerns. In this study, an interval type-2 fuzzy set based multi-criteria decision-making method is introduced for selecting the best location for electric charging stations. This method is improved by Simulated Annealing obtaining the best configuration of the parameters of the interval type-2 membership functions along with two different aggregation operators; linguistic weighted sum and average. The proposed overall reusable multi-stage solution approach is applied to a real-world public transport problem of the municipal bus company in Istanbul. The results indicate that the approach indeed improves the model, capturing the associated uncertainties embedded in the interval type-2 membership functions better, leading to a more effective fuzzy system. The experts confirm those observations and that Simulated Annealing improved interval type-2 fuzzy method achieves more reliable results for selecting the best sites for the electric bus charging stations

Accuracy and Uncertainty in Traffic and Transit Ridership Forecasts

Investments of public dollars on highway and transit infrastructure are influenced by the anticipated demands for highways and public transportations or traffic and transit ridership forecasts. The purpose of this study is to understand the accuracy of road traffic forecasts and transit ridership forecasts, to identify the factors that affect their accuracy, and to develop a method to estimate the uncertainty inherent in those forecasts. In addition, this research investigates the pre-pandemic decline in transit ridership across the US metro areas since 2012 and its influence on the accuracy of transit forecasts. The sample of 1,291 road projects from the United States and Europe compiled for this research shows that measured traffic is on average 6% lower than forecast volumes, with a mean absolute deviation of 17% from the forecast. Higher volume roads, higher functional classes, shorter time spans, and the use of travel models all improved accuracy. Unemployment rates also affected accuracy—traffic would be 1% greater than forecast on average, rather than 6% lower, if we adjust for higher unemployment during the post-recession years (2008 to 2014). Forecast accuracy was not consistent over time: more recent forecasts were more accurate, and the mean deviation changed direction. Similarly for 164 large-scale transit projects, the observed ridership was about 24.6% lower than forecasts on average. The accuracy depends on the mode, length of the project, year the forecast was produced as well as socio-economic and demographic changes from the production to observation year. In addition, we have found evidence of recent changes in transit demand to be affecting the transit ridership forecast accuracy. From 2012 to 2018, bus ridership decreased by almost 15% and rail ridership decreased by about 4% on average across the metropolitan areas in the United States. This decline is unexpected, because it coincided with the period of economic and demographic growth: indicators typically associated with rising transit ridership. We found that the advent of new mobility options in ride hailing services, bike and scooter shares as well as declining gas prices and increasing transit fares have the highest impact on ridership decline. Adjusting the ridership forecasts for these factors in a hypothetical scenario saw an improved transit ridership forecast performance. Despite the advances in modeling techniques and the availability of rich travel data over the years, expecting perfect forecasts (where observations are equal to the forecasts), may not be prudent because of its forward-facing nature. Forecasts need to convey their inherent uncertainty so that planners and policymakers can take that into account when they are making any decision about a project. The existing methods to quantify the uncertainty rely on flawed assumptions regarding input variability and interaction and are significantly resource intensive. An alternate method is one that considers the uncertainty inherent in the travel demand models themselves based on empirical evidence. In this research, I have developed a tool to quantify the uncertainty in traffic and transit ridership forecasts through a retrospective evaluation of the forecast accuracy from the two largest available databases of traffic and transit ridership forecasts. The factors associated with the accuracy and the recent decline in transit ridership lead the formulation of quantile regression as a new method to quantify the uncertainty in forecasts. Together with a consideration of decision intervals or breakpoints where a project decision might change, such ranges can be used to quantify project risk and produce better forecasts

Towards Sustainable Transport and Mobility

Small island states are one of the most affected areas by sea-level rise, and sustainable transport development is crucial to their transition towards resiliency. However, their special spatial situations, insularity, geographic remoteness, small populations, and small economies resulted in high transport costs and car dependencies. The book moves away from the conventional focus on urban areas in the Global North and tourism. It gives a different perspective on sustainable transport, travelling, and commuting in the Caribbean and Europe. The authors provide research-based insights and show the state-of-the-art and future approaches for policy-makers, academics, and practitioners. Even beyond small island state research, the book offers an innovative outlook

Regional public transport : The balancing act of service planning

This thesis addresses the demand for more knowledge regarding regional public transport (between urban areas or to and from rural areas). More specifically, the aim is to develop a better understanding of the effects of different service planning decisions in terms of different trade-offs and their impacts on the overarching objectives of public transport provision. The studied trade-offs concern, for example, stop spacing in rural areas and the distribution of departures between peak hours and periods of lower travel demand.The thesis includes four research papers with different orientations relative to the overarching aim. The first paper is a literature review that explores preferences in regional public transport and how different quality attributes influence modal choice, demand, and customer satisfaction. The other three papers contain in-depth studies of some regional rail, coach, and bus services in the southern Swedish region of Scania, employing different research setups and statistical analyses to enable detailed examination of some important aspects of the service planning trade-offs.The results suggest that the trade-offs can be more complex than they may seem. For instance, stop spacing is commonly debated and assessed as a trade-off between travel time and spatial coverage. However, the results of this thesis demonstrate that stop spacing on regional bus services is not so much about travel time as it is about reliability. This is particularly evident for rural bus stops where buses rarely need to stop to pick up or drop off passengers. Also, the coverage aspect of the trade-off is complex, as higher service quality extends the catchment areas around the stops, not least by increasing the use of bicycles and cars as access modes.Regarding the distribution of departures between peak and off-peak periods, the results of this thesis show that reasonable off-peak service levels are valuable not only for providing possibilities to access activities beyond school and work, but also for attracting new patronage. Despite low patronage levels on some off-peak departures, such departures may contribute substantially to the overall patronage.The main contribution of the thesis is twofold. First, it sheds light on the balancing act that public transport service planning entails. Second, it highlights the regional perspective and shows that the differences between local and regional public transport affect the trade-offs that exist at the core of service planning

Infrastructure Project Failures in Colombia

Due to poor civil engineering practices, natural disasters, corruption, the sabotage of infrastructure associated with Colombia’s armed conflict, and the politicisation of large infrastructure projects, Colombia is spending a significant amount annually on improving and rebuilding relatively new infrastructure. As the country’s population and economy continue to grow, so do its economic loses. This rapid literature review synthesises findings from academic, practitioner, and policy literature published in the past five years that discuss the factors that influence the recurrence of infrastructure project failures in Colombia and the public procurement checks and balances that been adopted to reduce their likelihood. Poor civil engineering is associated with inadequate initial design and design changes, an insufficient initial budget, lack of supervision, unexpected events, a lack of professional experience and competence, inadequate quality of work, poor budget and resource management and a lack of knowledge of construction and planning policy (Forcada, et al., 2017). In some cases, policies of social inclusion have resulted in the employment of local inexperienced contractors and workers. These major defining characteristics lead to a high rate of reconstruction and unnecessary effort in repeating poorly completed or incomplete work resulting in budget overruns. In ageing infrastructure, a preference for new construction over maintenance has resulted in increasingly deteriorated existing infrastructure, further increasing failure rates. Natural disasters are mostly associated with extreme rainfall events and earthquakes and can cause frequent flooding and landslides which impact important transport corridors. Heavy rainfall further complicates the maintenance and operation of surface transport by inhibiting repairs and upgrades (Wettling, et al., 2015). Corruption is a serious hurdle for the government and companies operating or investing in Colombia’s infrastructure. Various factors contribute to corruption including organised crime, drug trafficking, a lack of government transparency, and weak regulations for securing investments and their monitoring. To address this the Government of Columbia (GoC) is trying to improve transparency and access to information and to strengthen the legal framework and government structures (International Monetary Fund, 2018). Infrastructure sabotage mainly perpetrated by guerrilla forces and criminal groups (the “BACRIM”, formerly the paramilitary groups) , during the course of Colombia’s 50+ year armed conflict, has resulted in frequent attacks on oil and electricity infrastructure. The politicisation of large infrastructure projects. An ongoing series of papers by IABD (2018, forthcoming) on megaprojects in Latin American highlight how infrastructure megaprojects tend to be politicised – whereby political criteria and elections often dominate decision-making. Meanwhile, prefeasibility studies, feasibility studies and evaluations are often dominated by political actors and processes, and by the construction companies or the financiers of the projects. Colombia’s gross domestic product (GDP) has tripled over the past decade, however inadequate and insufficient infrastructure is a major threat to its economy, and improving its infrastructure is needed to boost the country’s competitiveness. Although significant investment in infrastructure has been taking place in Colombia, infrastructure project failures are severely constraining the impacts of these investments. The literature suggests that corruption is the major reason for the ineffectiveness of public procurement checks and balances. Efforts to improve public sector organisation by ring-fencing agencies/activities historically prone to corruption his has been led by a number of government anti-corruption initiatives including the establishment of the National Infrastructure Agency (ANI)