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Le Conseil d'Etat, juridiction suprême en réseau : une illustration
No full textnonouinon-rechercheNationa
Approximating the optimal sequence of acquisitions and sales with a capped budget
No full textWe introduce and study the approximability of the following problem. There is a set of useful objects that are available for purchase, and another set of useless objects that can be sold. Selling useless objects generates revenue which allows to acquire useful objects. We search for a sequence of decisions (buying or selling objects) which optimizes either the number of purchased objects or their global utility. One of the constraints is that, at any time, only a limited amount of money can be held.nonouirechercheInternationa
Protection of transport infrastructures against major accidents in land use planning policies. A decision support approach
No full textUsers of transport infrastructures nearby hazardous plants may represent important populations potentially impacted by a major accident. Toulouse catastrophe in 2011 has been an illustrative example as it strongly impacted highway users. Therefore, transport infrastructure users (Roads and railways mainly) represent a population to be protected within a land use planning policy as it is the case for inhabitants.Accordingly, this paper presents a decision support approach aiming to help local stakeholders identifying the most cost effective measures to protect transport infrastructures from major accidental consequences. The suggested approach takes in account both technical and participatory constraints with the aim of offering an equal chance to all involved stakeholders to understand the issues under discussion and formulate opinions and values.After a description of the French regulatory context, the major technical difficulties related to transport infrastructures protection will be described before introducing the main technical choices adopted by the team. Finally, a decision support procedure is described and a real case study presented.This work is strongly embedded in the French regulatory context. However, we believe the decision support structure as fully adaptable to other regulatory contexts.nonouirechercheInternationa
Social Choice Theory
No full textSocial choice theory is the formal study of collective decision-making. Its modern version was initiated by both Arrow and Black and is concerned with the construction of a social preference out of individual preferences.nonouirechercheInternationa
Hierarchical Data Topology Based Selection for Large Scale Learning
No full textThe amount of available data for data mining, knowledge discovery continues to grow very fast with the era of Big Data. Genetic Programming algorithms (GP), that are efficient machine learning techniques, are face up to a new challenge that is to deal with the mass of the provided data. Active Sampling, already used for Active Learning, might be a good solution to improve the Evolutionary Algorithms (EA) training from very big data sets. This paper investigates the adaptation of Topology Based Selection (TBS) to face massive learning datasets by means of Hierarchical Sampling. We propose to combine the Random Subset Selection (RSS) with the TBS to create the RSS-TBS method. Two variants are implemented, applied to solve the KDD intrusion detection problem. They are compared to the original RSS, TBS techniques. The experimental results show that the important computational cost generated by original TBS when applied to large datasets can be lightened with the Hierarchical Sampling.nonouirechercheInternationa
Efficient Feedback Collection for Pay-as-you-go Source Selection
No full textArticle No. 1Technical developments, such as the web of data and web data extraction, combined with policy developments such as those relating to open government or open science, are leading to the availability of increasing numbers of data sources. Indeed, given these physical sources, it is then also possible to create further virtual sources that integrate, aggregate or summarise the data from the original sources. As a result, there is a plethora of data sources, from which a small subset may be able to provide the information required to support a task. The number and rate of change in the available sources is likely to make manual source selection and curation by experts impractical for many applications, leading to the need to pursue a pay-as-you-go approach, in which crowds or data consumers annotate results based on their correctness or suitability, with the resulting annotations used to inform, e.g., source selection algorithms. However, for pay-as-you-go feedback collection to be cost-effective, it may be necessary to select judiciously the data items on which feedback is to be obtained. This paper describes OLBP (Ordering and Labelling By Precision), a heuristics-based approach to the targeting of data items for feedback to support mapping and source selection tasks, where users express their preferences in terms of the trade-off between precision and recall. The proposed approach is then evaluated on two different scenarios, mapping selection with synthetic data, and source selection with real data produced by web data extraction. The results demonstrate a significant reduction in the amount of feedback required to reach user-provided objectives when using OLBP.nonouirechercheInternationa
Drinking water supply in resilient cities: Notes from L’Aquila earthquake case study
No full textDisasters impacts on urban environment are the result of interactions among natural and human systems, which are intimately linked each other. What is more, cities are directly dependent on infrastructures providing essential services (Lifeline Systems, LS). The operation of LS in ordinary conditions as well as after disasters is crucial. Among the LS, drinking water supply deserves a critical role for citizens. The present work summarizes some preliminary activities related to an ongoing EU funded researchproject. The main aim of the paper is to define a System Dynamic Model (SDM) to assess the evolution of resilience of a drinking water supply system in case of natural disasters, with particular attention to the role of both ‘structural’ and ‘non-structural’ parameters. Reflections are carried out on L’Aquila (Italy) case study, since drinking water infrastructures were significantly stressed during the 2009 earthquake, causing a limited functionality in the aftermath of the event. Furthermore, the reallocation of citizens in temporary shelters determined a change in the demand pattern, requiring a dynamic adaptation of the infrastructure. Based on an innovative approach to resilience, the model was developed also to simulate different emergency management scenarios, corresponding to different disaster management strategies.nonouirechercheInternationa
Integrating Organizational Risk Analysis and Participatory Network Mapping for flood risk management
No full textThe complexity of the interaction network among the different actors involved in flood risk management makes it difficult for risk managers to fully understand the different interconnections among the key elements, i.e. actors, knowledge and tasks. Due to their limited understanding of thenetwork, the risk managers fail to strengthen the social capital embedded in the network, reducing its role in supporting risk management. A method based on the integration between Organization Risk Analysis and Participatory Network Mapping is described in this work. The method aims at enhancing the risk managers’ understanding of the interaction network and, in doing so, at enabling the collective decision-making process for the management of risk interaction network. The method has beenexperimentally implemented for flood risk management in Lorca (Spain).nonouirechercheInternationa
Efficient computation of the search region in multi-objective optimization
No full textMulti-objective optimization procedures usually proceed by iteratively producing new solutions. For this purpose, a key issue is to determine and efficiently update the search region, which corresponds to the part of the objective space where new nondominated points could lie. In this paper we elaborate a specific neighborhood structure among local upper bounds. Thanks to this structure, the update of the search region with respect to a new point can be performed more efficiently compared to existing approaches. Moreover, the neighborhood structure provides new insight into the search region and the location of nondominated points.nonnonrechercheInternationa