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Zaghdoud R.,Institute Superieur Of Gestion Of Tunis | Zaghdoud R.,Ecole Centrale Lille | Mesghouni K.,Ecole Centrale Lille | Dutilleul S.C.,IFSTTAR Institute Francais des science et Technologies des Transports | And 2 more authors.
Studies in Informatics and Control | Year: 2015

The handling operations performed in ports require the use of equipment operating in a dynamic environment. Some tasks may not be fully carried out due to equipment failure or power breakdown that may occur particularly with the automated guided vehicles (AGV). The unavailability of equipment such as AGV has important consequences in terms of respecting the deadlines of different operations that a port should perform, such as the loading and unloading operations of ships. This situation can aggravate if there are also traffic problems in the port with some inaccessible network nodes. A part of the equipment will be blocked or the operations will take longer than expected if they don`t take the optimal path to connect the loading/unloading points and storage areas. These reasons confirm the usefulness of establishing a robust system able to resolve the problem of assigning containers in the static and dynamic environments. In a previous work, we developed a system for assigning containers in a static environment. In order to improve this method, we devote this paper to the study of the robustness of our system to the dynamic environment of the port. The numerical tests included in this paper show an adequate performance of our method for this particular dynamic environment. © ICI Bucharest 2010-2015. Source


Zaghdoud R.,Institute Superieur Of Gestion Of Tunis | Collart-Dutilleul S.,IFSTTAR Institute Francais des science et Technologies des Transports | Ghedira K.,Institute Superieur Of Gestion Of Tunis | Mesghouni K.,Ecole Centrale Lille | Zidi K.,Institute Superieur Of Gestion Of Tunis
Proceedings - 2013 IEEE International Conference on Systems, Man, and Cybernetics, SMC 2013 | Year: 2013

The problem of assignment containers to AIVs in a container terminal is a complex problem, it is a combination of several problems; the dispatching problem, the vehicles routing problem and the scheduling problem. Each problem of these depends on some criteria; this makes the global problem as a multi-criteria problem. To solve this type of problem, the idea is to consider it like a mono-objective problem depending on each criterion separately. An aggregation function is calculated according to different criteria. The coefficient value of each criterion is proposed by an expert, these values can give the nearest Pareto front solution. The approach proposed in this work is a hybrid approach; genetic algorithm and Dijkstra algorithm. This approach is tested with different numbers of vehicles, for each problem separately, in order to have the best solution. The numeric results show the performance of our approach for the multi-objective problem. © 2013 IEEE. Source


Degraeve B.,University of Nimes | Granie M.-A.,IFSTTAR Institute Francais des science et Technologies des Transports | Pravossoudovitch K.,Aix - Marseille University | Lo Monaco G.,Aix - Marseille University
Transportation Research Part F: Traffic Psychology and Behaviour | Year: 2015

The aim of this study was to investigate the specific contents of the social representations (SR) associated with men and women drivers and examine the effects of the social insertions of individuals (i.e., age, sex and socio-economic status) on the content and structure of these SR. A preliminary study with 414 French participants identified thematic content associated with men and women drivers using the verbal association method. Based on these themes, 833 French participants, equally distributed by age group (from 12 to 50 years-old and over), sex and socioeconomic status (SES), were asked to answer a questionnaire on men (N = 422) or women (N = 411) drivers. The results show that each of these SR is organized around three factors: incompetence, prudence and lack of self-control for women drivers; carelessness, skills and self-control for men drivers. In-group favoritism bias can be noted in both groups as male participants, more than female ones, rated men drivers as having self-control and women drivers as lacking self-control, whereas female participants, more than male ones, perceived men drivers as careless and women drivers as prudent. Despite this phenomenon, more male respondents than female ones in all age groups seemed to believe that women are not competent at driving, whereas both sexes seem to agree that men have good driving skills. Among most age groups, three characteristics associated with men drivers (confidence, speed and pleasure of driving) and four characteristics associated with female drivers (caution, civil, compliance with rules and vigilance) emerged as central in the SR. The SR associated with men drivers appeared to be stable and shared across age groups, whereas the SR associated with women drivers appeared more mixed, heterogeneous and unstable with age. Female participants with higher SES consider women drivers as more incompetent, less prudent and more lacking self-control than female participants with lower SES. © 2015 Elsevier Ltd. All rights reserved. Source


Papadimitriou E.,National Technical University of Athens | Lassarre S.,IFSTTAR Institute Francais des science et Technologies des Transports | Yannis G.,National Technical University of Athens
Transportation Research Part F: Traffic Psychology and Behaviour | Year: 2016

The objective of this research is the development of pedestrian crossing choice models on the basis of road, traffic and human factors. For that purpose, a field survey was carried out, in which a panel of 75 pedestrians were asked to take 8 short walking trips (each one corresponding to a different walking and crossing scenario) in the Athens city centre in Greece, allowing to record their crossing behaviour in different road and traffic conditions. The same individuals were asked to fill in a questionnaire on their travel motivations, their mobility characteristics, their risk perceptions and preferences with respect to walking and road crossing, their opinion on drivers, etc. The walking and crossing scenarios' data were used to develop mixed sequential logit models of pedestrian behaviour on the basis of road and traffic characteristics. The modelling results showed that pedestrian crossing choices are significantly affected by road type, traffic flow and traffic control. The questionnaire data were used to estimate human factors (components) of pedestrian crossing behaviour by means of principal component analysis. The results showed that three components of pedestrian crossing behaviour emerge, namely a "risk-taking and optimisation" component reflecting the tendency to cross at mid-block in order to save time, etc., a "conservative" component, concerning individuals with increased perceived risk of mid-block crossing, who also appear to be frequent public transport users, and a "pedestrian for pleasure" component, bringing together frequent pedestrians, walking for health or pleasure, etc. The introduction of these components as explanatory variables into the choice models resulted in improvement of the modelling results, indicating that human factors have additional explanatory power over road and traffic factors of pedestrian behaviour. Therefore, the development of integrated choice and latent variables models appears to be an appropriate field for further research. © 2015 Elsevier Ltd. Source


Betaille D.,IFSTTAR Institute Francais des science et Technologies des Transports | Peyret F.,IFSTTAR Institute Francais des science et Technologies des Transports | Voyer M.,ESGT Ecole Superieure des Geometres et Topographes
Journal of Navigation | Year: 2015

Urban positioning using the Global Positioning System (GPS) is challenging because of multipath. Urban canyons limit open sky visibility, and cause signal reflection and diffraction, resulting in significant satellite range measurement errors. The investigations reported here have been carried out in a French project called Inturb (an acronym derived from integrity and urban positioning). So far, the project has had two phases: first, a simple Three-Dimensional (3D) geometrical city modelling, called Urban Trench, has been developed and engineered manually from data sets collected in different cities. Positioning improvement in terms of accuracy was quantified where the model could be applied. Second, this modelling has been automated, based on the standard national BD Topo ® map database for France, with promising results. This geometrical modelling makes it possible to distinguish between line-of-sight satellite signals and those from non-line-of-sight. The latter, apparently bona fide, signals are caused by strong reflections, usually from buildings with a lot of steel and glass in their construction. A correction of the pseudo-range measurements of the latter is also computed and applied in the position estimator. Positioning accuracy is improved, whilst availability is kept at its maximum. In the study both manual and automatic 3D models are used in extensive experimental campaigns. Results are: first, the possibility to cover entirely any urban area in the country; second, the reduction of the median error in 3D by more than 50% on data collected in Nantes, Paris and Toulouse for a total duration of nearly ten hours; third, the compliance with standards used in most embedded maps and geographical information systems, including an assessment of the trade-off between the model simplicity and the positioning improvement. Copyright © 2015 The Royal Institute of Navigation. Source

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