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Volcanic structures are inhomogeneous on a number of scales. Quantifying whether such inhomogeneities result in a physical and mechanical anisotropy is important to improve large-scale volcano and volcano-geothermal modelling. It is, however, currently challenging to account for such anisotropy because there are very few experimental studies that quantify the physical and mechanical property anisotropy expected for volcanic rocks. Here, we measure the porosity, permeability, P-wave velocity, thermal properties, uniaxial compressive strength (UCS), and static Young's modulus of samples from five trachyandesite lavas from the Chaîne des Puys (Massif Central, France) that have been cored in three arbitrary orthogonal directions. We show, using X-ray computed tomography, that the pores in the most anisotropic lava are oblate spheroids, with a major axis 2−5 times larger than their minor axis, that have a shape preferred orientation. This lava is an order of magnitude less permeable, has a P-wave velocity ~25% lower, and has a UCS and Young's modulus ~50% lower when measured perpendicular to the major pore axis. The observed physical and mechanical anisotropy is therefore the result of a pore shape preferred orientation. We conclude that, alongside large-scale sources of anisotropy such as stratified lavas, modellers should also consider incorporating a physical and mechanical anisotropy in the volcanic rocks forming a particular layer in the development of models that seek to incorporate greater complexity. Incorporating additional complexities in modelling, where and when possible, will provide the most accurate predictions and therefore the most reliable information for a given volcano or geothermal reservoir. [ABSTRACT FROM AUTHOR]

The use of bio-based building materials is a sustainable opportunity to reduce the environmental footprint associated with the construction sector. The achievement of this objective is primely achieved through the valorisation of vegetable waste, resulting in a reduction in the use of primary source material and waste generation. Within the scope of this study, the focus is directed towards research concerning the thermal, acoustic, and fire behaviour properties of bio-based building materials. This study conducts a comprehensive bibliometric analysis encompassing all documents meeting these criteria within the Scopus database, spanning two decades, from 2003 to 2023. The comprehensive analysis covered a total of 1081 documents, which were analysed. This analysis furnishes insight into various facets, including the temporal evolution of publications, journals boasting the highest publication counts and impact, influential research areas, countries with substantial contributions and their collaborative patterns, noteworthy affiliations, prolific authors, and seminal documents, alongside recurrent keywords. The objective of this comprehensive study is to provide a detailed analysis of the documents published up to the present day, in order to identify research gaps and potential opportunities in this field, to assist new researchers interested in the subject. The analysis reveals that bio-based building materials have gained substantial attention over the past decade. With each passing year, the published documents have increased their impact and become more specific, underscoring the growing importance of this subject. This evolution has also fostered a broader network of researchers engaged in this field. However, it is noteworthy that the characterization of these materials focuses predominantly on their thermal properties, while research avenues related to acoustic and fire properties remain less explored and present opportunities for future investigation. • This study contributes to identify research gaps and potential opportunities in the field of bio-based building materials. • Studies in bio-based building materials have shown an annual growth of the 25% since 2014, being a topic on the rise. • France and China are the countries with the highest scientific publication on bio-based building materials. • Keywords play a crucial role in making visible the research within bio-based building materials. • "Thermal Conductivity" and "Thermal insulation" are the most repeated keywords in this field. [ABSTRACT FROM AUTHOR]

Most amphibians use both aquatic and terrestrial habitats. While the aquatic phase attracted considerable interest, terrestrial habitat use is often less investigated. We studied diurnal refuge selection in the Midwife toad in Western central France. We used a factorial design and tested the effect of refuge type (wood versus rubber boards) and substrate (wet sawdust versus bare soil). Most animals were observed under refuges with sawdust substrate. An interaction between refuge type and temperature was detected with higher presence probability under rubber refuges at low temperature. Conflicting hydric and thermic requirements are likely determinants of the observed pattern. [ABSTRACT FROM AUTHOR]

[Display omitted] • Urban building energy modeling based on probabilistic district characterization has been used to quantify uncertainty on the flexibility. • The duration event and the decrease in the set point temperature are key parameters in the flexibility potential. • A dynamic model of the thermal comfort of occupants puts forward the rejection risk of flexibility. • The effectiveness of the envelope properties plays an indirect role. With the increasing share of intermittent renewable energy sources in the energy mix, demand-side flexibility is likely to play a key role in the future. For buildings, flexibility is defined as the ability to shift their energy consumption away from "peak periods" i.e. high-demand periods of the electrical network. In France, these episodes occur mainly during the wintertime due to the significant demand for space heating. To achieve flexibility objectives, we explore an indirect control strategy at district scale by adjusting the dwelling thermostat during peak periods. The study is conducted over 337 dwellings in order to better predict the load curve by taking advantage of the aggregation effect. Three main research questions are addressed in relation to the assessment of flexibility potential: (i) the effect of aggregation, (ii) the identification of the most influencing factors, including occupant behavior, and (iii) the quantification of uncertainties. Using an urban building energy modeling tool populated with various national data sources (building envelope, energy class of equipment, etc), we perform a sensitivity analysis on 22 parameters representing the geometry, the appliances, the building characteristics, the occupants, and the grid. The output indicator is the average power shifted during the flexibility (or demand response) event. From this analysis, 7 parameters appear as being the most influential. A regression analysis on these parameters is performed, depending on both the duration of the event and the typology of district. The results show that the duration of the flexibility event and the occupant pre-selected temperature change are the most influential parameters. It results to approximately ± 90 W of uncertainty on an average potential of 290 W of shiftable power per household in a recent district. Furthermore, the occupants are highlighted as making a significant contribution to flexibility. Finally, we observed that the thermal properties investigated with the study of an old fabric district play a key role. Low thermal performance means high heating consumption and increased flexibility potential, but a similar relative uncertainty. [ABSTRACT FROM AUTHOR]

[Display omitted] • Distributed Temperature sensing is used to monitor borehole flows in fractured media. • Fast analytical solutions are used to invert the temperature profile into flow profile • The potential of DTS data for monitoring the dynamics of fractured media is shown. Fractured aquifers are known to be very heterogeneous with complex flow path geometries. Their characterization and monitoring remain challenging despite the importance to better understand their behavior at all spatial and temporal scales. Heat and correspondingly temperature data have gained much interest in recent years and are often used as a tracer for characterizing groundwater flows. In the current work, a fast computer code is developed using Ramey and Hassan and Kabir analytical solutions which converts the temperature profile to the flow rate profile along the borehole. The method developed is validated through numerical simulations. A global sensitivity study recognizes the media thermal properties as the most influential parameters. For testing the method in the field, fiber-optic distributed temperature sensing (FO-DTS) data were used to monitor the dynamic behavior of fractured aquifers at the borehole scale at the Ploemeur-Guidel field site in Brittany, France. DTS data are used to infer the flow rates in the different sections of a fractured wellbore (flow profile) and calculate the contribution of each fracture to the total flow. DTS data were acquired for about three days in three different hydraulic conditions corresponding to two different ambient flow conditions and one pumping condition. Flow profiling using distributed temperature data matches satisfactorily with results from heat-pulse flow metering performed in parallel for cross-checking. Moreover, flow profiling reveals the daily variations of ambient flow in this fractured borehole. Furthermore, it shows that during ambient flowing conditions, shallow and deep fractures contribute roughly equally to the total flow while during the pumping condition, the deepest fractures contribute more to the total flow, suggesting a possible reorganization of flow and hydraulic heads depending on the hydraulic conditions. Thus, although the proposed method (DTS data and proposed framework) may be costlier and is based on indirect characterization through temperature measurements, it provides real-time monitoring of complex fracture interactions and recharge processes in fractured media. Thus, this method allows for a full analysis of the temporal behavior of the system with a simple and fast analytical model. Furthermore, thanks to its narrow width, DTS can be used and installed in boreholes for long-term monitoring while heat-pulse flow metering may lead to head losses in the borehole and may not be always possible depending on some borehole conditions. One of the limitations of the approach proposed is the proper knowledge of the thermal properties of media required to infer the flow rate from the temperature. Nevertheless, surface rate measurement can be useful to constrain these properties and reduce the flow profiling uncertainty. Thus, the method proposed appears to be an interesting and complementary method for characterizing borehole flows and groundwater dynamics in fractured media such as for instance, monitoring the recharge dynamic. [ABSTRACT FROM AUTHOR]

• D-optimum criterion is applied to select an optimal experiment duration. • Identifiability of parameters is demonstrated. • Thermal conductivity is estimated over the reduced measurement plan. • Parameter estimation problem is solved with hybrid optimization method. • Reliability of the model for one year experiment is achieved. The in situ estimation of the thermal properties of existing building wall materials is a computationally expensive procedure. Its cost is highly proportional to the duration of measurements. To decrease the computational cost a methodology using a D-optimum criterion to select an optimal experiment duration is proposed. This criterion allows to accurately estimate the thermal properties of the wall using a reduced measurement plan. The methodology is applied to estimate the thermal conductivity of the three-layer wall of a historical building in France. Three different experiment sequences (one, three and seven days) and three spatial distributions of the thermal conductivity are investigated. Then using the optimal duration of observations the thermal conductivity is estimated using the hybrid optimization method. Results show a significant reduction of computational time; and reliable simulation of physical phenomena using the estimated values. [ABSTRACT FROM AUTHOR]