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The purpose of this paper is to provide a traffic route selection strategy based on minimum carbon dioxide (CO₂) emission by vehicles over different route choices.

The study used queuing theory for Markovian M/M/1 model over the road junctions to assess total time spent over each of the junctions for a route with junctions in tandem. With parameters of distance, mean service rate at the junction, the number of junctions and fuel consumption rate, which is a function of variable average speed, the CO₂ emission is estimated over each of the junction in tandem and collectively over each of the routes.

The outcome of the study is a mathematical formulation, using queuing theory to estimate CO₂ emissions over different route choices. Research finding estimated total time spent and subsequent CO₂ emission for mean arrival rates of vehicles at junctions in tandem. The model is validated with a pilot study, and the result shows the best vehicular route choice with minimum CO₂ emissions.

Proposed study is limited to M/M/1 model at each of the junction, with no defection of vehicles. The study is also limited to a constant mean arrival rate at each of the junction.

The work can be used to define strategies to route vehicles on different route choices to reduce minimum vehicular CO₂ emissions.

Proposed work gives a solution for minimising carbon emission over routes with unsignalised junctions in the tandem network.

The purpose of this paper is to fit a logit model for dry bulkers transporting grains through the Panama Canal versus alternative routes destined to East Asia, originating on the US Gulf and East Coast. This is with the purpose of better understanding the attributes.

In this paper, grain transits both through the Panama Canal and alternative routes, which are examined, and a logit model is developed to explain the route decision from a carrier/vessel operator point of view.

Transit draft is the most important attribute in the route decision process for grains according to this study. Also, Panamax bulkers are the preferred vessel size into China, especially through the Cape of Good Hope route, impacting Panama Canal’s market share for grains.

This research used only a full year of grain traffic data approximating fiscal year 2018 (October 1, 2017 to September 30, 2018). Data will come mostly from the Panama Canal transit data and observations using IHS’s Market Intelligence Network (MINT).

This paper is highly dependent on visual observations of grains vessels through alternative routes using AIS data from MINT software.

In mass gatherings, a large number of people gather at a single location. To ensure safety of these people, adequate crowd management strategies are essential. Specifically, in case of an emergency, efficient evacuation can save the lives of many people. This paper aims to develop various control strategies for efficient evacuation, including providing information of routes, changing the physical layout and controlling the behavior of evacuees.

Mathematical models have been developed for optimal decision-making and analysis of the effect of these control strategies during evacuation. A global search with Sequential Quadratic programming is used to increase the likelihood of obtaining the optimal solution to these models. Further, an illustrative evacuation example is presented to test the efficacy of the models.

The results of the illustrative example demonstrate that the models and their corresponding strategies can bring significant benefits for efficient evacuation.

The models developed can play a significant role in helping the security staff execute evacuation better at an operational level. The authors’ models can also have implications at the strategic level for the crowd manager.

Efficient strategies and optimal decision-making during evacuation can save lives of people. These models can develop efficient strategies that can save lives of people.

This paper fulfills need to study the effect of various control strategies on evacuation efficiency for a large area and its complete network.

Emergency evacuation plans are often developed under the assumption that evacuees will use wayfinding strategies such as taking the shortest distance route to their nearest exit. The purpose of this paper is to analyze empirical data from a wildfire evacuation analyzed to determine whether evacuees took a shortest distance route to their nearest exit and to identify any alternate wayfinding strategies that they may have used.

The wildfire evacuation analysis presented in this paper is the outcome of a natural experiment. A post-fire online survey was conducted, which included an interactive map interface that allowed evacuees to identify the route that they took. The survey results were integrated with several additional data sets using a GIS. Network analysis was used to compare the routes selected by evacuees to their shortest distance routes, and statistical hypothesis testing was employed to identify the wayfinding strategies that may have been used.

The network analysis revealed that 31 percent of evacuees took a shortest distance route to their nearest exit. Hypothesis testing showed that evacuees selected routes that had significantly longer distances and travel times than the shortest distance routes, and indicated that factors such as the downhill slope percentage of routes and the elevation of exits may have impacted the wayfinding process.

This research is best regarded as a spatiotemporal snapshot of wayfinding behavior during a single wildfire evacuation, but could inspire additional research to establish more generalizable results.

This research may help emergency managers develop more effective wildfire evacuation plans.

This research presents an analysis of an original data set that contributes to the broader body of scientific knowledge on wayfinding and spatial behavior during emergency evacuations.

For many years it has been recognised that physical distribution is a promising area for the application of system modelling techniques. Freight transportation systems offer a rare combination of tractability and realistic opportunity for improvement. Large‐scale freight network models, for example, can be useful to state and national transportation system planners. Among other uses, the models permit examination of the impact of proposed changes on modal competition and on the flow of traffic over certain routes. Carriers may also find network models useful for their more limited planning purposes, such as determining the consequences of changes in a physical system. For example, facilities or links can be added, deleted, or modified in order to analyse the effects on tonnage and mode of shipment for the affected commodities. Specific routes can be added or eliminated in order to determine the worth of using those routes. Finally, firms can change the commodity tonnage between specific origins and destinations in order to assess future transportation needs.

This paper aims to analyse available multimodal transport route variations for iron ore shipments from northwest Australia to northeast China, focusing on a major iron and steel manufacturer.

The research is focused on a case study and uses an established cost model as a framework, for the first time, in the context of heavy bulk cargo shipments. Field interviews and a questionnaire form the principal methods of primary data collection. The characteristics of bulk iron ore transport flow are analysed against traditional criteria and an appraisal of the transport infrastructure in north east China is made, considering both road and rail options, and various possible combinations for transport being evaluated. All factors affecting modal choice in the region are examined, including cargo volume, weight, and value, transport distance, transit time, transport costs and schedule reliability.

The volumes of iron ore moved are large, with a high weight‐to‐volume ratio, and shipments are regular. The research initially confirms that sea and rail transport combinations are the most appropriate for the movement of iron ore. However, where rail transport corridors are congested, provided that the transport distances are not too great, road haulage appears to be an effective substitute and the most competitive multimodal transport route, at least in the short to medium term, is found to be a rail‐sea‐road combination via Port Bayuquan in China.

The research focuses on the delivery of iron ore to one major steel manufacturer in northeast China; so findings may not be transferable to other companies or circumstances.

The paper first demonstrates that, for heavy, high volume cargoes concentration of flows on to one corridor, perhaps under the control of one service provider, maximises scale economies, but works against competition and route/mode choice. Second, it demonstrates that, for long haul shipments of iron ore, port variations and modal differences for inland transport yield only marginal differences in overall logistics costs.

An assessment of high volume/heavy/low value cargoes such as iron ore has not previously been undertaken using this cost model. This paper therefore provides an original analysis of such supply chains.

The purpose of the study is to implement a methodology intended to identify the links between the microclimatic quality of urban routes and the behavior of pedestrians. This document will open up new opportunities for the development of urban open spaces and facilitate decision-making for urban decision-makers.

The methodology intended to identify the links between the microclimatic quality of urban routes and the behavior of pedestrians is deployed in two stages. The first stage represents a microclimatic characterization of the pedestrian routes. The second step represents a behavioral characterization of these same journeys, based on the on-site video observation of the pedestrians.

The analysis of the results obtained by applying this method shows that the physical factors of the urban environment in the two climatic seasons (winter, summer) significantly influence the choice of routes, the percentage of route use, the speed of travel and the frequency of user stops.

The authors have recently observed that the issue of the influence of microclimatic factors on the behavior of pedestrians, and more particularly their movements, has only rarely been addressed. It is therefore in this context that the authors would like to provide, through this article, some technical solutions for analysis and characterization as well as some answers to the problem of the influence of microclimatic factors on pedestrian movements.

It has been witnessed that many incidents of crowd evacuation have resulted in catastrophic results, claiming lives of hundreds of people. Most of these incidents were a result of localized herding that eventually turned into global panic. Many crowd evacuation models have been proposed with different aspects of interests. The purpose of this paper is to attempt to bring together many of these aspects to study evacuation dynamics.

The proposed agent-based model, in a hypothetical physical environment, uses perception maps for routing decisions which are constructed from agents’ personal observations of the surroundings as well as information gathered through distant communication. Communication is governed by a trust model which measures the authenticity of the information being shared. Agents are of two types; emotional and rational. The trust model is combined with a game-theoretic model to resolve conflict of agents’ own type with that of types of agents in the neighborhood.

Evacuation dynamics in different environmental and exit strategies are evaluated on the basis of reduced herding and evacuation time. Using this integrated information sharing model, agents gain an overall view of the environment, sufficient to select the optimal path towards exits with respect to reduced herding and evacuation time.

The proposed model has been formulated and established using an agent-based simulation integrating important modeling aspects. The paper helps in understanding the interplay between technological and humanistic aspects in smart and pervasive environments.

The purpose of this paper is to explore whether children adopt a survey or a route approach when seeking information in a virtual world (VW), and whether their approach differs depending on whether they are experiencing positive or negative motivation. Different models were used based on disparate spatial recognition and conceptual abilities.

In total, 127 children operated a three-dimensional VW interface then they filled out a questionnaire. Structural equation modeling was employed to analyze weighted relationships among latent variables. Motivation (positive vs negative), information-seeking model (heuristic survey or detailed route) and the spatial markers, and complexity of patterns of the VW were examined.

The authors discovered that a highly motivated child tends to take a central route in the process of information seeking, whereas a child experiencing negative emotions and uncertainty prefers a survey approach using spatial markers to obtain information. In short, the type of motivation influences whether children adopt a heuristic or detailed perspective when searching for information on virtual interfaces.

It is believed that users combine perceptual activities (low-level cognition) with conceptual activities (high-level cognition) in order to save energy. Yet this study is the first to investigate the conditions under which children are prone to utilize spatial markers (based on visual working memory) or the sequencing of patterns (based on verbal working memory) to find information in a heuristic or detailed fashion. This study provides a fresh perspective regarding perceptual and conceptual integration for information visualization technology.

The skillsets of science, technology, engineering and mathematics (STEM) graduates are widely recognised to be important for economic prosperity. At the same time, it is broadly accepted that in England there is a need to increase the number of people studying STEM degree courses and working in STEM. However, despite decades of interventions post-16, STEM participation rates remain lower than projected requirements. Some research reports suggest a lack of positive attitudes towards these subjects and aspirations amongst some social groups. As these debates continue, official reports such as those released by the Department for Education show these patterns from the labour market and higher education (HE) extend to both attainment and participation in science and math in school.

In this paper, the authors summarise the authors' findings from the analysis of official reports, policy documents and major research reports focussing on attainment in school science and math and post-compulsory STEM participation.

The authors identify the problematic ways in which STEM subject choices are made across the student life cycle and then discuss how the leaky pipeline metaphor can be ambiguous and needs to be used with caution.

Some aspects identified here warrant further research and will be of particular interest to researchers, practitioners and policymakers.

In this new report, the authors identify the problematic ways in which STEM subject choices are made across the student life cycle in England and then discuss how the leaky pipeline metaphor can be ambiguous and needs to be used with caution.