Knowledge-based Consistency Index for Fuzzy Pairwise Comparison Matrices

Abstract—Fuzzy AHP is today one of the most used Multiple Criteria Decision-Making (MCDM) techniques. The main argument to introduce fuzzy set theory within AHP lies in its ability to handle uncertainty and vagueness arising from decision makers (when performing pairwise comparisons between a set of criteria/alternatives). As humans usually reason with granular information rather than precise one, such pairwise comparisons may contain some degree of inconsistency that needs to be properly tackled to guarantee the relevance of the result/ranking. Over the last decades, several consistency indexes designed for fuzzy pairwise comparison matrices (FPCMs) were proposed, as will be discussed in this article. However, for some decision theory specialists, it appears that most of these indexes fail to be properly “axiomatically” founded, thus leading to misleading results. To overcome this, a new index, referred to as KCI (Knowledge-based Consistency Index) is introduced in this paper, and later compared with an existing index that is axiomatically well founded. The comparison results show that (i) both indexes perform similarly from a consistency measurement perspective, but (ii) KCI contributes to significantly reduce the computation time, which can save expert’s time in some MCDM problems

A state-of the-art survey & testbed of Fuzzy AHP (FAHP) applications

As a practical popular methodology for dealing with fuzziness and uncertainty in Multiple Criteria Decision-Making (MCDM), Fuzzy AHP (FAHP) has been applied to a wide range of applications. As of the time of writing there is no state of the art survey of FAHP, we carry out a literature review of 190 application papers (i.e., applied research papers), published between 2004 and 2016, by classifying them on the basis of the area of application, the identified theme, the year of publication, and so forth. The identified themes and application areas have been chosen based upon the latest state-of-the-art survey of AHP conducted by Vaidya and Kumar (2006). To help readers extract quick and meaningful information, the reviewed papers are summarized in various tabular formats and charts. Unlike previous literature surveys, results and findings are made available through an online (and free) testbed, which can serve as a ready reference for those who wish to apply, modify or extend FAHP in various applications areas. This online testbed makes also available one or more fuzzy pairwise comparison matrices (FPCMs) from all the reviewed papers (255 matrices in total). In terms of results and findings, this survey shows that: (i) FAHP is used primarily in the Manufacturing, Industry and Government sectors; (ii) Asia is the torchbearer in this field, where FAHP is mostly applied in the theme areas of Selection and Evaluation; (iii) a significant amount of research papers (43% of the reviewed literature) combine FAHP with other tools, particularly with TOPSIS, QFD and ANP (AHP’s variant); (iv) Chang’s extent analysis method, which is used for FPCMs’ weight derivation in FAHP, is still the most popular method in spite of a number of criticisms in recent years (considered in 57% of the reviewed literature)

Knowledge-based Consistency Index for Fuzzy Pairwise Comparison Matrices

Abstract—Fuzzy AHP is today one of the most used Multiple Criteria Decision-Making (MCDM) techniques. The main argument to introduce fuzzy set theory within AHP lies in its ability to handle uncertainty and vagueness arising from decision makers (when performing pairwise comparisons between a set of criteria/alternatives). As humans usually reason with granular information rather than precise one, such pairwise comparisons may contain some degree of inconsistency that needs to be properly tackled to guarantee the relevance of the result/ranking. Over the last decades, several consistency indexes designed for fuzzy pairwise comparison matrices (FPCMs) were proposed, as will be discussed in this article. However, for some decision theory specialists, it appears that most of these indexes fail to be properly “axiomatically” founded, thus leading to misleading results. To overcome this, a new index, referred to as KCI (Knowledge-based Consistency Index) is introduced in this paper, and later compared with an existing index that is axiomatically well founded. The comparison results show that (i) both indexes perform similarly from a consistency measurement perspective, but (ii) KCI contributes to significantly reduce the computation time, which can save expert’s time in some MCDM problems

L'infiltration des eaux pluviales en milieu urbain : conséquences sur l'écosystème aquatique souterrain

International audienceL'urbanisation induit une imperméabilisation des sols et une augmentation du ruissellement, réduisant ainsi la recharge de la nappe souterraine. La gestion des eaux de pluie consiste à les collecter et les infiltrer vers la nappe qui est protégée de la pollution par des processus auto-épurateurs localisés dans le sol et la zone insaturée. Les dynamiques de la matière organique et des micro-organismes ont été suivies dans les eaux de surface et les eaux souterraines en amont et en aval des trois systèmes d'infiltration (SI). Les teneurs en Carbone Organique dissous (COD) biodégradable et réfractaire ont été mesurées sur l'eau et la croissance des biofilms a été suivie à l'aide des substrats artificiels incubés dans le milieu. Le COD diminue fortement au cours de l'infiltration, mais sa fraction biodégradable demeure plus forte en aval de SI, tout comme les biofilms qui sont stimulés par les infiltrations en biomasse et en diversité. ABSTRACT Urbanization increases impervious surfaces and stormwater runoff reducing groundwater recharge. Stormwater management mainly consists in the collection of rain water and its infiltration to the aquifer, which is protected by the self-purification capacity of the soil and the unsaturated zone. The dynamics of organic matter and microorganisms were studied in surface water and in groundwater upstream and downstream of three stormwater infiltration systems (SIS). Dissolved Organic Carbon (DOC) concentrations were measured in surface and in ground waters, while biofilm dynamics were studied using artificial substrates incubated in the waters. DOC sharply decrease from surface water to the groundwater, but the biodegradable fraction of DOC was higher downstream than upstream of the SIS and the biofilms were stimulated by the infiltration for both biomass and bacterial diversity

Rapid response to the M_w 4.9 earthquake of November 11, 2019 in Le Teil, Lower Rhône Valley, France

On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to large damages it produced in several villages. InSAR interferograms indicated a shallow rupture about 4 km long reaching the surface and the reactivation of the ancient NE-SW La Rouviere normal fault in reverse faulting in agreement with the present-day E-W compressional tectonics. The peculiarity of this earthquake together with a poor coverage of the epicentral region by permanent seismological and geodetic stations triggered the mobilisation of the French post-seismic unit and the broad French scientific community from various institutions, with the deployment of geophysical instruments (seismological and geodesic stations), geological field surveys, and field evaluation of the intensity of the earthquake. Within 7 days after the mainshock, 47 seismological stations were deployed in the epicentral area to improve the Le Teil aftershocks locations relative to the French permanent seismological network (RESIF), monitor the temporal and spatial evolution of microearthquakes close to the fault plane and temporal evolution of the seismic response of 3 damaged historical buildings, and to study suspected site effects and their influence in the distribution of seismic damage. This seismological dataset, completed by data owned by different institutions, was integrated in a homogeneous archive and distributed through FDSN web services by the RESIF data center. This dataset, together with observations of surface rupture evidences, geologic, geodetic and satellite data, will help to unravel the causes and rupture mechanism of this earthquake, and contribute to account in seismic hazard assessment for earthquakes along the major regional Cévenne fault system in a context of present-day compressional tectonics

C. Voisin - Cubic fourfolds, hyper-Kähler manifolds and their degenerations: Complex analytic and differential geometry 2017

There at least three families of hyper-K ̈ahler manifolds built from cubic fourfolds, the most recently discovered one being the compactified intermediate Jacobian fibrations I constructed with Laza and Sacca. In a joint work with Koll ́ar, Laza and Sacca, we provide an easy way to compute their deformation types, by proving that if the central fiber of a degeneration of hyper-Kähler manifolds has one component which is not uniruled, then after base-change the family becomes fiberwise birational to a family of smooth hyper-Kähler manifolds

Utilisation de billes de verre comme substrats artificiels pour la caractérisation des communautés microbiennes dans les nappes phréatiques : mise au point méthodologique

International audienceDans un objectif d’étudier l’impact de l’infiltration des eaux pluviales en milieu urbain sur les eaux souter- raines, il est nécessaire de développer des outils permettant d’évaluer la qualité microbiologique des nappes phréatiques. La difficulté majeure des études microbiologiques des nappes phréatiques réside dans l’échantillonnage des bactéries. Un système d’échantillonnage passif, par incubation de substrats artificiels dans la nappe, pourrait permettre d’obtenir une image plus fiable de la diversité des micro-organismes transitant dans ces systèmes. Le but de cette étude a été de tester l’efficacité d’un substrat artificiel, des billes de verre de différents diamètres (4, 6, 8 et 10 mm), pour le piégeage et le développement de biofilm dans deux eaux ayant des concentrations en bactéries et en nutriments contrastées. Les résultats montrent que les bactéries peuvent se développer sous forme d’un biofilm à la surface des billes de verre et que le type d’eau a une influence majeure sur l’échantillonnage passif. Ces premières expériences ont aussi permis de conclure qu’il est plus intéressant en terme de biomasse bactérienne d’utiliser dans le dispositif d’échantillonnage des billes d’un diamètre de 8 ou 10 mm plutôt que des billes d’un diamètre inférieur. En effet, les billes de grandes tailles semblent favoriser les échanges entre la surface des billes et le milieu environnant, favorisant la colonisation et la crois- sance microbienne

Aquifer recharge with stormwater runoff in urban areas: Influence of vadose zone thickness on nutrient and bacterial transfers from the surface of infiltration basins to groundwater

International audienceStormwater in␣ltration systems (SIS) have been built in urban areas to reduce the environmental impacts of stormwater runoff. In␣ltration basins allow the transfer of stormwater runoff to aquifers but their abilities to retain contaminants de- pend on vadose zone properties. This study assessed the in␣uence of vadose zone thickness (VZT) on the transfer of inor- ganic nutrients (PO34␣, NO␣3 , NH+4 ), dissolved organic carbon (total -DOC- and biodegradable -BDOC-) and bacteria. A ␣eld experiment was conducted on three SIS with a thin vadose zone (b3 m) and three SIS with a thick vadose zone (N10 m). Water samples were collected at three times during a rainy period of 10 days in each in␣ltration basin (stormwater runoff), in the aquifer impacted by in␣ltration (impacted groundwater) and in the same aquifer but upstream of the in␣ltration area (non-impacted groundwater). Inorganic nutrients, organic matter, and dissolved oxygen (DO) were measured on all water samples. Bacterial community structures were investigated on water samples through a next-generation se- quencing (NGS) scheme of 16S rRNA gene amplicons (V5-V6). The concentrations of DO and phosphate measured in SIS-impacted groundwaters were signi␣cantly in␣uenced by VZT due to distinct biogeochemical processes occurring in the vadose zone. DOC and BDOC were ef␣ciently retained in the vadose zone, regardless of its thickness. Bacterial transfers to the aquifer were overall low, but data obtained on day 10 indicated a signi␣cant bacterial transfer in SIS with a thin va- dose zone. Water transit time and water saturation of the vadose zone were found important parameters for bacterial transfers. Most bacterial taxa (N60%) from impacted groundwaters were not detected in stormwater runoff and in non- impacted groundwaters, indicating that groundwater bacterial communities were signi␣cantly modi␣ed by processes as- sociated with in␣ltration (remobilization of bacteria from vadose zone and/or species sorting)