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It is usually assumed that faulty bearings produce second-order cyclostationary (CS2) signals, and thus the natural process for their diagnostic analysis involves first the removal of first-order cyclostationary (CS1) components, such as from gears, followed by amplitude demodulation of an 'informative' frequency band, and subsequent envelope analysis, in which the spectrum of the (squared) envelope is inspected for signs of a fault, typically manifesting as discrete frequency components at or near one of the expected fault frequencies, the latter calculated from basic kinematic relationships. However, recent theoretical research, supported by empirical evidence from the aero industry, has shown that bearing signals are in fact not purely CS2, but rather exhibit both CS1 and CS2 properties, dominant in the lower and higher frequency ranges, respectively, with the 'crossover' between these ranges proportional to machine speed. Thus, for high-speed bearings, where the frequency range available for analysis may span only a handful of fault frequency harmonics, the relative importance of CS1 signal content is far greater than for lower speed applications, and it can no longer be assumed that the envelope spectrum is the optimal diagnostic tool. These and other issues associated with high-speed bearing diagnostics are discussed in this paper, using as an example the aircraft engine data provided by Safran for the diagnostic contest at the 2015 Surveillance 8 Conference in Roanne, France. The objective of the paper is to guide the reader in the analysis of high-speed bearing signals, pointing out in particular the ways in which the required analysis techniques differ from the 'conventional wisdom' of the diagnostics field, most of which is based on more common, lower speed applications. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of a hitherto barely known conceptual problem in the foundations of arithmetic. An unknown type of number, so-called complex numbers, first emerged in 18th century France and became connected with the claim of non-commutativity of their multiplication. These first French practitioners are here analysed, along with examination of the impact of the introduction of the metric decimal system. International dissemination of the notion is then analysed, in particular in the case of Brazil. The paper concludes by looking at the mathematical foundations of multiplying (physical) quantities. [ABSTRACT FROM AUTHOR]

Nuclear power is largely analysed as a contested energy production technology with a focus on the factors for the success or failure of the development of nuclear programmes but little questioning of the usages associated with this energy production. By concentrating specifically on the question of usage, this article sheds light on an original timeline of the development of nuclear power in France in the 1970s. It highlights the existence of an intense debate on the means of using the energy that would be produced by this industry and on the models of technical, political, economic and spatial organisation of the energy system that would result. Based on an analytical work of several historical archival funds, this paper brings into light how three sociotechnical regimes were in competition to organize the French energy system during the development of the national nuclear programme. From an historical geography perspective, this paper provides insights for a critical rethinking of the development of nuclear programmes as well as for the politics surrounding the phase-out of nuclear power. • The means of using nuclear energy were intensely discussed during the development of the French programme. • Three technical, political, economic and spatial models of nuclear development were in competition. • The development of nuclear power can follow several spatial routes. • The legacy of the electric heating choice restricts the construction of a new energy transition. [ABSTRACT FROM AUTHOR]

The number of bridges worldwide is extensive, making it financially and technically challenging for the authorities to install a structural health monitoring (SHM) system and collect large quantities of data for every bridge. Transfer learning has gained relevance in the last few years to extend the SHM concept for most bridges, while minimizing costs with monitoring systems and time with data measurement. It can be especially suitable for bridges structurally similar and replicated extensively, like overpasses integrated into highways. Therefore, this paper intends to lay down the foundations of transfer learning for SHM of bridges and to highlight the importance of the quality of knowledge transferred across different bridges for damage detection. Transfer Component Analysis, Joint Distribution Adaptation, and Maximum Independence Domain Adaptation methods are applied to data sets from different bridges, where classifiers have access to labeled training data from one bridge (source domain) and unlabeled monitoring test data from another bridge (target domain) that present similarities. The effectiveness of those methods is compared through the classification performance using real-world monitoring data sets collected from the Z-24 Bridge in Switzerland, and the PI-57 and PK 075+317 Bridges in France. [ABSTRACT FROM AUTHOR]

Although the 'organization of space' is said to be one of the defining characteristics of modern human behavior, the identification and documentation of such organization has proven to be elusive, especially as rendered in artifact patterning. Without directly comparing artifact patterns within multiple sites, there is no benchmark with which to conclude one site to be more or less 'organized' than another. We can objectively identify patterns within the distribution of archaeological materials, but the decision of whether that patterning constitutes as 'organized' is entirely subjective without a comparative model. In this paper, I present the results of a study in which the spatial distribution of artifacts within nine Middle and Upper Paleolithic sites in France are directly compared to one another, and discernible changes in patterning can be identified. The differences in spatial patterning between the Middle and Upper Paleolithic sites suggest that the organization of space likely became increasingly formalized into and throughout the Upper Paleolithic alongside other cultural norms of behavior. Though more sites are needed to thoroughly document this phenomenon, this study suggests that direct comparisons of spatial patterning have the potential to yield more objective results on the question of spatial organization. [ABSTRACT FROM AUTHOR]

The paper deals with the automatic analysis of real-life telephone conversations between an agent and a customer of a customer care service ( ccs ). The application domain is the public transportation system in Paris and the purpose is to collect statistics about customer problems in order to monitor the service and decide priorities on the intervention for improving user satisfaction. Of primary importance for the analysis is the detection of themes that are the object of customer problems. Themes are defined in the application requirements and are part of the application ontology that is implicit in the ccs documentation. Due to variety of customer population, the structure of conversations with an agent is unpredictable. A conversation may be about one or more themes. Theme mentions can be interleaved with mentions of facts that are irrelevant for the application purpose. Furthermore, in certain conversations theme mentions are localized in specific conversation segments while in other conversations mentions cannot be localized. As a consequence, approaches to feature extraction with and without mention localization are considered. Application domain relevant themes identified by an automatic procedure are expressed by specific sentences whose words are hypothesized by an automatic speech recognition ( asr ) system. The asr system is error prone. The word error rates can be very high for many reasons. Among them it is worth mentioning unpredictable background noise, speaker accent, and various types of speech disfluencies. As the application task requires the composition of proportions of theme mentions, a sequential decision strategy is introduced in this paper for performing a survey of the large amount of conversations made available in a given time period. The strategy has to sample the conversations to form a survey containing enough data analyzed with high accuracy so that proportions can be estimated with sufficient accuracy. Due to the unpredictable type of theme mentions, it is appropriate to consider methods for theme hypothesization based on global as well as local feature extraction. Two systems based on each type of feature extraction will be considered by the strategy. One of the four methods is novel. It is based on a new definition of density of theme mentions and on the localization of high density zones whose boundaries do not need to be precisely detected. The sequential decision strategy starts by grouping theme hypotheses into sets of different expected accuracy and coverage levels. For those sets for which accuracy can be improved with a consequent increase of coverage a new system with new features is introduced. Its execution is triggered only when specific preconditions are met on the hypotheses generated by the basic four systems. Experimental results are provided on a corpus collected in the call center of the Paris transportation system known as ratp . The results show that surveys with high accuracy and coverage can be composed with the proposed strategy and systems. This makes it possible to apply a previously published proportion estimation approach that takes into account hypothesization errors. [ABSTRACT FROM AUTHOR]

In this paper, we propose a nonlocal reaction-diffusion model of bluetongue disease with seasonality, spatial heterogeneous structure, and periodic extrinsic incubation period. We introduce the basic reproduction ratio R 0 for this model and show that the disease-free periodic solution is globally attractive if R 0 < 1 , while the disease is uniformly persistent if R 0 > 1. Further, we obtain the global attractivity of the positive steady state in the case where all the coefficients are constants. Numerically, we study the bluetongue transmission in Corsica Island, France, and investigate the impact of some model parameters on R 0. We find that the disease risk may be underestimated if the spatial heterogeneity is ignored. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the motives behind an intrinsic value of decision rights. Based on a series of experimental treatments conducted in France and Japan, we measure how much of such potential value stems from (i) a desire for independence from others, (ii) a desire for power, or (iii) a desire for self-reliance. We find that both Japanese and French subjects attach a significant intrinsic value to hold control. Surprisingly, we find that self-reliance is the only significant motive behind it in both countries. [ABSTRACT FROM AUTHOR]

In parallel to phytoplankton community dynamics, transparent exopolymeric particles (TEP) and exopolymeric substances (EPS) were investigated along the salinity gradient of a temperate estuary (Seine estuary, Normandy, France) over the course of a year. The phytoplankton community was mainly dominated by marine diatom species (especially Skeletonema sp., Nitzschia sp., and Paralia sulcata ) associated with a spring bloom of pico-eukaryotes and the development of Cryptophyceae in summer. The decreases in species richness and salinity were correlated along the estuary and a significant exponential relationship between species richness and primary production was identified. Concentrations of TEP and EPS (soluble and bound carbohydrates) are highly dynamic in this estuary and can reach respectively 69 mgC L −1 , and 33 mgC L −1 . TEP distribution was mainly related to physical factors (hydrodynamics, maximum turbidity zone formation and sediment resuspension) probably produced by stressed or dying phytoplankton, while EPS appeared to be excreted during the phytoplankton spring bloom. Soluble and bound EPS appear to be related to Skeletonema sp. and Cryptophyceae occurrences. This paper presents the dynamic pattern of these carbon pools, which play an important role in the trophic network and influence the flocculation processes involved in the fate of both organic and inorganic matter. [ABSTRACT FROM AUTHOR]

A number of freshwater fish particularly migratory species are currently under threat. As the pressure of recreational fishing has intensified, this activity needs to be more regulated to halt the decline of threatened fish stocks. This paper presents results of an economic valuation study of anglers' preferences for a change in the rules applying to Twaite shad fisheries in south-western France. Twaite shad has become a "near-threatened" species, with the same IUCN status as the Atlantic salmon. As shad recreational angling continues to be open access, new regulations are required to limit recreational harvest in support of a management strategy to prevent stock reduction even to foster stock recovery. We combined a deliberative choice experiment with open group discussion to obtain an in-depth understanding of anglers' preferences between two types of traditional regulatory instrument – a license fee or a bag limit. The closure of the fishery served as the reference scenario. The results indicate that the majority of anglers were aware of the decline of Twaite shad stocks. The recreational value of the species remains high, especially for those who already target migratory species. Although econometric estimations show that there are heterogeneous preferences across anglers, there were support for a change toward a bag limit, and an aversion for a high-priced licence fee. The findings also provided two key insights to improve recreational fishing management and preservation policy for threatened species. The communication of observation data on fish stock could not be considered as a sufficient ecological information to ensure threatened species monitoring leads to an effective co-management with anglers' community. Anglers' aversion to loss can be seen as a behaviour mechanism towards the preservation of the species rather than to its use. • The first economic valuation study aimed at Twaite shad preservation. • Anglers who target or not the species were interviewed to reveal their preference for harvest regulations. • Deliberative choice experiment combined with open group discussion was employed. • There was consensual support for a change toward a bag limit if control is reinforced. • Respondents who do not identify themselves as shad anglers are more willing to support a permanent closure of the fisheries. [ABSTRACT FROM AUTHOR]

We present a two-method spherical approach to archeomagnetic dating based on directional variations of the geomagnetic field after vector treatment of all data, including individual in situ structure-level data used to calculate the reference variation curve and the archeomagnetic direction to be dated. In this paper, the reference curve for France was determined from a compilation of data acquired from kiln structures using a sliding window technique in which the varying durations and time shifts between windows are fixed according to the temporal distribution of individual reference data, as well as the bivariate extension of Fisher's statistics. The first dating method involves identifying the time interval(s) in which the direction to be dated is closest to the mean directions that define the reference curve. The angles between the direction to be dated and reference curve directions, and the Fisher probability density function allow us to derive a coincidence probability density curve, from which it is possible to estimate a 95% probability level-based dating interval. The second dating method involves the determination of an archeomagnetic date in which the direction to be dated is statistically identical to a dated reference curve direction at the 95% confidence level. This approach is much more restrictive than the previous method because it requires an excellent agreement between the test and reference directions to obtain a dating result, while the first method is only based on relative proximity. Using examples of archeomagnetic dating, we show that these two methods are complementarity and should be applied jointly to account for some of the limitations inherent in archeomagnetic dating, particularly due to the dispersion of the reference structure-level data. • We use a vector treatment of archeomagnetic directions for dating purposes. • A dating method involving the maximum proximity to a reference curve was developed. • A method involving the statistical compatibility to a reference curve is also used. • Both dating methods are applied to French archeomagnetic direction data. • We show the effectiveness of the joint use of these two archeomagnetic dating methods. [ABSTRACT FROM AUTHOR]

In the karstic regions of the South of France, caves were used as water source during the Late Neolithic. Different strategies of water collection were put in place, the most frequent being the positioning of very large ceramic containers under trickle points. Functional studies, and more specifically use-wear analysis, are seldom used approaches applied to ceramic assemblages and the identification of post-depositional processes remains a major challenge that affects interpretation, particularly in karstic contexts. In the case of Le Claux, this approach shed light on a possible storage of acid liquid, that was potentially fermented. This paper aims both to contribute to the discipline of use-wear studies applied to ceramic material by offering a new method to differentiate natural and man-made wears, and to offer a better understanding of cave activities in the Late Neolithic of the South of France. • The function of Neolithic cistern-caves is renewed by a use-alteration analysis on pots. • A new method to differentiate ceramic use-alteration from natural and post-depositional alterations is proposed. • Use-wear of ceramic vessels from a cave context may reveal the production of acid fermented liquids. [ABSTRACT FROM AUTHOR]

In this paper we question whether prior cross-national differences in food attitudes still exist and if so, to what extent. Due to societal evolutions such as sedentarism and globalization, international variations in food attitudes may not be as pronounced as currently believed. A cross-sectional web-based survey was carried out in the United States, the United Kingdom, France and Belgium. A total of 2167 respondents (52% women; mean age = 39.0 years, SD = 11.4) participated. To successfully combat obesity, a joint approach focusing on food choice and physical activity is required; therefore we included behavioral measures by means of choice tasks for these two important drivers. Further, the extent to which respondents subscribe to the unhealthy = tasty intuition, together with health and taste interest were investigated. Socio-demographic information and self-reported heights and weights were also incorporated. Logistic regressions were fitted with weight status as the dependent variable and the attitudinal and behavioral measures as independent variables. Our findings indicate that having a higher interest in healthy eating decreases the chance of being overweight (odds = 0.88) and believing that unhealthy food is tasty significantly increases the chance of being obese by 1.18 times. Overall, we find that food attitudes have largely converged across the countries we investigated. [ABSTRACT FROM AUTHOR]

The infiltration of secondary treated effluent (STE) into the soil downstream of wastewater treatment plants is becoming increasingly common in a climate change context. In STE infiltration, STE is discharged onto the soil over a large surface allowing for a gradual infiltration of the water. This paper investigates a novel time-lapse electrical resistivity tomography strategy to evaluate the impact of STE infiltration on the water pathways of two planted loamy-soil trenches located in a Fluvisol region in southwestern France. The system has been monitored for 3 years using discontinuous monitoring of electrical resistivity tomography during four saline tracer tests. Results show that: 1) the new methodology has successfully highlighted the evolution of water pathways in the soil over time; 2) such evolution is in agreement with reeds root distribution in the trenches which seems to be affected by water quality i.e. sludge losses and TSS, for this study case. Indeed, for the infiltration trench receiving STE with lower pollution levels (2.2 mg TSS. L−1, 26 mg COD. L−1), the infiltration capacity is maintained over the years (4–6 mm h−1) and reed roots developed deeper in the soil. A sludge deposit present at the bottom of the second infiltration trench receiving higher pollution levels (7.2 mg TSS. L−1, 45 mg COD. L−1, plus episodic sludge release) could lead roots to develop close to the surface affecting the infiltration capacity which did not evolve over time. This work highlights the importance of long-term flow pathway monitoring in understanding the hydraulic behavior of infiltration surfaces submitted to STE. [Display omitted] • New methodology for monitoring preferential flow pathways. • Infiltration is monitored by discontinuous saline tracer tests and time-lapse ERT. • Water flow pathways in soil evolve over time depending on water quality. [ABSTRACT FROM AUTHOR]

• Paleolithic artwork with overlaping engravings provides a dynamic analyses. • The succession of the animals themes suggests story tellings. • The realization of the artwork is similar to art performance. • 3D of the panel in its space lets consider an audience watching the art in progress. • Social cohesion through stories, tellings or myths recalled in a peculiar space. This paper investigates the cognitive role of the palimpsest in cave art through the case of the Cussac Cave Grand Panel, the main engraved assemblage from this sepulchral and decorated site dated from the Middle Gravettian period (31,200–28,700 cal BP). The technical, thematic and formal unity of this monumental panel yields evidence of a short time-span for its creation. The accurate study of the superimpositions in situ and on a high resolution 3D model leads to the conception of a Harris matrix like model. It attests to a global structuring based on privileged themes interactions (taxa associations, animation and scale of depictions, relative chronology). Considering Cussac Cave Grand Panel palimpsest as a dynamic composition, the paper discusses agency and practice of accumulation in one place in Palaeolithic cave art. In the perspective of "art as action" the dynamic composition could be considered as a performance which raises the question of the audience. The monumentality of the depictions, the physical space of the chamber and the panel setting would suggest two agents: the engraver as primary agent acting towards a potential collective audience as a secondary agent. In this social context we assume that the palimpsest could have been used as a way to share and reinforce common concepts in the community. Whatever the particular semantic content of Cussac cave rock art, this study testifies to the collective dimension of cave art palimpsests, unlike most works so far which considered these specific compositions as the expression of an individual relationship to the parietal images. Thus it brings new elements of discussion on the socio-cultural functions of cave art production and cave art sites in the Palaeolithic societies of Western Europe. [ABSTRACT FROM AUTHOR]

Sheep and goat are often herded together and show morphological similarities in their skeleton. Being able to identify archaeological remains of these two taxa to species level is particularly important for understanding and characterising past herding practices. Discrete criteria are now available to identify a large number of their bones and teeth, and quantitative approaches have been developed for post-cranial elements but not for mandible and isolated teeth. In this paper we explore the discriminating potential of geometric morphometrics to identify modern sheep and goat third lower molar and mandible and its application on archaeological specimens. The size and shape of the mandible and the third lower molar of 143 modern specimens (101 sheep and 42 goats) were quantified using 2D-landmark and sliding semi-landmarks geometric morphometric approaches. The results show that sheep and goat differ in terms of the size, shape, and form (i.e. size and shape together) in both studied elements. Classification accuracy of the two species reaches 93.3% (CI: 90.0–95.7%) for third lower molar shape, 62.7% (CI 57.1–68.6%) for third lower molar size, 95.2% (CI: 92.0–97.4%) for mandible shape and 84.0% (CI 81.6–86.8%) for mandible size. Form does not provide better classification than shape alone. Sex and age appear to have little impact on the ability to differentiate between sheep and goat, despite the two species displaying distinct sexual dimorphism and changes through age. The same methodology was then applied on 32 Middle Ages third lower molars from Missignac-Saint Gilles le Vieux, Aimargues, France. The identifications obtained through geometric morphometrics were only partially congruent with the identifications based on visual observations calling for caution in the interpretation and further investigations. Further research should include molecular identification of the archaeological specimens to assess whether the geometric morphometric identification can be made with confidence for all periods and all geographic areas. Nevertheless, the results obtained with the newly developed geometric morphometric protocols represent an important contribution toward a better understanding of past livestock husbandry practices. • Sheep and goat differ in their third lower molar and mandible size and shape. • Based on shape, 93% of the molar and 95% of the mandibles can be correctly identified. • Geometric morphometrics allow the identification of archaeological specimens. • Geometric morphometric and macroscopic identifications are only partially congruent. [ABSTRACT FROM AUTHOR]

This paper provides an empirical assessment of the effects of age and baseline health on the Value per Statistical Life (VSL) by reporting the results of a compensating wage differential for occupational fatality risk in France. We exploit Constances, a novel population-based cohort that combines respondents' full medical history, elicited using face-to-face interviews with physicians, with respondents' work history, extracted from administrative records. Focusing on blue-collar males, aged between 20 and 59 years of age, we find an average VSL estimate of at least 6.5 million euros. Our results suggest that VSL decreases with age and with better baseline health. [ABSTRACT FROM AUTHOR]

To assess human health risks related to the environment, it is necessary to aggregate exposure from multiple sources. The objective of this paper was to propose a relevant approach to combine data from heterogeneous populations and methodologies. Five different methods based on Monte-Carlo simulations were tested and compared. Differences were: taking into account or not stratification variable, timeline to assign exposure factors and concentration and way to account for concentration correlations. The methods were applied to estimate lead exposure from food, dust, soil, air, and tap water or French children aged between six months and three years old. Comparing results' uncertainty, it is recommended to 1) select a reference population representative of the target population, 2) select stratification variables to combine surveys, and 3) simulate a new population by randomly sampling individuals in the reference population and simultaneously assigning human exposure factors and environmental concentrations from other surveys in integrating correlations (MC1S). No difference was observed when taking into account correlations using vectors of determinist data from one survey or rank of correlations with the Iman-Conover method. Regardless the methods used to combine data, dust was the main exposure source, followed by soil and in a less extent by food. Exposures from air and tap water were found to be insignificant for most children. • Five calculation processes were tested to combine dietary and environmental surveys. • Resampling individuals and variables decrease the uncertainty. • Use stratification variables to combine surveys limits risk of error. • The tested methods to account for correlations between exposure factors gave similar results. • Dust and soil were main exposure sources of children in France. [ABSTRACT FROM AUTHOR]

The present paper reports on a series of field experiments aiming to characterise the functioning of a man-engineered strongly forced salt-wedge estuary: the lower estuary of the Adour river, France. Bottom-moored velocity measurements and surface boat surveys have been performed under low river discharge conditions, for both neap and spring tides, in order to provide a well-documented reference framework to understand the dynamics of water masses, turbulence and suspended particulate matter (SPM) transport in the lower estuary. An additional campaign has been carried out in high river discharge conditions. This first documented in-situ study of the Adour lower estuary demonstrates its variability in terms of hydrological regimes, from salt-wedge to partially mixed regimes depending on tidal and discharge conditions. Turbulent properties showed a significant response to the variations of salinity structure, with higher values when stratification is minimal. At spring tide, a tidal variation between mixing conditions on the ebb and the flood is revealed by ADCP measurements, with higher values extended up to the surface during the ebb. The link between turbulent mixing and suspended sediment concentration is straightforward during the ebb. During the flood, the suspended sediment concentration (SSC) seems related to the salt-wedge entrance re-suspension and stratification-induced turbulence damping. No stable Estuarine Turbidity Maximum (ETM) has been observed during the field experiment in the lower Adour estuary. • The first extensive study of the lower Adour estuary. • The observations reveal a very high variability of the salinity structure, which has never been reported in the literature. • No ETM has been identified in the present experimental conditions. • The Adour estuary dynamics is discussed with respect to the roles of tide, river discharge and human engineering. [ABSTRACT FROM AUTHOR]