Approach to Design Behavioural Models for Traffic Network Users - Choice of transport mode

Our research work concerns the development of a multimodal urban traffic simulator designed to be a tool of decision-making aid similar to a game where in the user-player can test different scenarios by immersion in a 3D virtual city. Our approach is based on the activity-based model and the multi-agent technology. The implemented result is a hybrid simulator connecting numerical simulation and behavioural aspects coming from real data. This paper is focused on two points: firstly, we introduce how a final user (the traffic regulator) instantiates and assembles components so as to model a city and its urban traffic network, secondly, we present the use of Dempster-Shafer theory in the context of discrete choice modelling. Our approach manipulates input variables in order to test realistic representations of behaviours of agent categories in a decision-making process. The traffic modelling is based on a questionnaire elaborated from standard arrays of Taguchi. The significant variables and interactions are determined with the analysis of variance which suggests a reduced model describing the behaviour of a particular social category. The belief theory is used to take into account the doubt of some respondents as well as for the preferences redistribution if the number of alternatives changes. The effects of external traffic conditions are also quantified to choose a'robust'alternative and to use the agents'memory

Site selection for electric cars of a car-sharing service

This study is carried out in the framework of SUCCESS (Smaller Urban Communities in CIVITAS for Environmentally Sustainable Solutions), an European project funded by the European Commission under the CIVITAS program. These demonstration projects provide a means of testing out a wide range of projects in a number of cities and the results of the evaluation will assist in showing which were successful, in what way and how that was achieved. One of these projects is the car-sharing implementation. Carsharing is defined as a self service which allows to each subscriber for reaching a vehicle, for the duration and the way of his choice. In the current state, where the impacts of the pollution and the congestion of cities are increasingly acute, the car-sharing service can be an attractive complement for other means of transportation. For it, this type of service must ensure a high level of temporal and spatial availability. For the managers of a car-sharing service it means an efficient management of the existing system and for the local authorities it means the study of the opportunities of its extension. This work proposes to the decision makers an approach of aid to the extension of the service based on the modeling of the preferences of the potential users

Expression of Aspergillus hemoglobin domain activities in Aspergillus oryzae grown on solid substrates improves growth rate and enzyme production

DNA fragments coding for hemoglobin domains (HBD) were isolated from Aspergillus oryzae and Aspergillus niger. The HBD activities were expressed in A. oryzae by introduction of HBD gene fragments under the control of the promoter of the constitutively expressed gpdA gene. In the transformants, oxygen uptake was significantly higher, and during growth on solid substrates the developed biomass was at least 1.3 times higher than that of the untransformed wild-type strain. Growth rate of the HBD-activity-producing strains was also significantly higher compared to the wild type. During growth on solid cereal substrates, the amylase and protease activities in the extracts of the HBD-activity-producing strains were 30-150% higher and glucoamylase activities were at least 9 times higher compared to the wild-type strain. These results suggest that the Aspergillus HBD-encoding gene can be used in a self-cloning strategy to improve biomass yield and protein production of Aspergillus specie

A branch-and-cut algorithm for the Team Orienteering Problem

The Team Orienteering Problem aims at maximizing the total amount of profit collected by a fleet of vehicles while not exceeding a predefined travel time limit on each vehicle. In the last years, several exact methods based on different mathematical formulations were proposed. In this paper, we present a new two-index formulation with a polynomial number of variables and constraints. This compact formulation, reinforced by connectivity constraints, was solved by means of a branch-and-cut algorithm. The total number of instances solved to optimality is 327 of 387 benchmark instances, 26 more than any previous method. Moreover, 24 not previously solved instances were closed to optimality