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Counterfactuals are central in causal human reasoning and the scientific discovery process. The uplift, also called conditional average treatment effect, measures the causal effect of some action, or treatment, on the outcome of an individual. This paper discusses how it is possible to derive bounds on the probability of counterfactual statements based on uplift terms. First, we derive some original bounds on the probability of counterfactuals and we show that tightness of such bounds depends on the information of the feature set on the uplift term. Then, we propose a point estimator based on the assumption of conditional independence between the counterfactual outcomes. The quality of the bounds and the point estimators are assessed on synthetic data and a large real-world customer data set provided by a telecom company, showing significant improvement over the state of the art. [ABSTRACT FROM AUTHOR]

This paper introduces the design of a reconfigurable transmitarray operating within the D-band frequency range (110–170 GHz). The transmitarray unit cell is composed of three metal layers and two quartz dielectric substrates. It achieves a 1-bit phase shift resolution through the alternating states of two innovative switches integrated into the active transmitting patch of the unit cell. To address the challenge of miniaturization in the D-band, compact switches compatible with the proposed unit cell dimensions are introduced. These switches are constructed using phase change materials (PCM) that change between amorphous and crystalline states when exposed to heat. The paper includes a full-wave simulation of the unit cell, demonstrating an insertion loss below 1.5 dB across a wide frequency band of 27%. Additionally, a 10 × 10 elements transmitarray is synthesized using a numerical tool and its theoretical results are compared to full-wave electromagnetic simulations for validation purposes. The results indicate that by incorporating the proposed switches into the unit cell, the transmitarray achieves promising reconfiguration capabilities within the D-band. Moreover, the paper presents the architecture of a command line designed to bias the PCM switches. Notably, this command line represents a novel approach, as it enables individual biasing of each PCM switch using direct current (DC). The influence of these command lines on the transmitarray’s performance is thoroughly investigated. Although there is a compromise in the 1-dB gain bandwidth, the overall behavior of the transmitarray remains encouraging. [ABSTRACT FROM AUTHOR]

Since the end of the Little Ice Age (LIA), Svalbard glaciers have undergone a net retreat in response to changing meteorological conditions. Located between 76°N and 80°N, western Spitsbergen has seen a climatic transition from a glacial to a paraglacial system. On the northern shore of the Brøgger Peninsula (northwest Spitsbergen), the average temperature increased by 3 °C between 1965 and 2015, and cold-based valley glaciers have retreated more than 1 km from their LIA limits. This rapid deglaciation has exposed large areas of glacigenic sediments being easily reworked by runoff. This has led to the formation of extensive glacier-river delta systems and coastal progradation. Post-LIA coastal progradation and formation of new landforms in Kongsfjorden have been controlled predominantly by substantial availability of glacial sediment. A combination of aerial photographic and field data has been employed to estimate the post-LIA evolution of coastal sandur deltas and their submarine parts (named here 'prodeltas'). The data set reveals that delta shoreline advance could have reached around 5 m/year. between 1966 and 1990 for the most energetic delta of Austre Lovenbreen, and around 4 m/year between 2011 and 2014 for the most energetic delta of Midtre Lovenbreen. The prodeltas registered a net growth from 2009 to 2012: the biggest, located in the prolongation of deltas of Austre Lovenbreen, measured 1033 m in length in 2009 and 1180 m in length in 2012. This substantial amount of sediment supplied in the fjord has an impact on the fjord ecology, especially on the benthic ecosystem. [ABSTRACT FROM AUTHOR]

In this paper, we consider second-order evolution equations with unbounded dynamic feedbacks. Under a regularity assumption, we show that observability properties for the undamped problem imply decay estimates for the damped problem. We consider both uniform and non-uniform decay properties. [ABSTRACT FROM AUTHOR]

Storm Xynthia (February 2010) was responsible for a large sea surge along the French Atlantic coast. It resulted in the flooding of low-lying coastal areas during the night. Urbanized areas were impacted and 41 people died by drowning in their homes. The location and type of construction of the houses in the affected area contributed to the death toll. The fact that the inadequacy of construction with regard to coastal flood hazard could lead to death was one of the most important lessons of the storm. The French government decided to buy back and scrap the most dangerous buildings hit by Xynthia. In order to prevent future deaths by drowning, we have developed a tool (the V.I.E. index) to identify houses where a risk of death due to a coastal flood cannot be excluded. The goal is to propose individual-based solutions for risk mitigation of residential houses. This tool uses a micro-scale-level analysis along with four criteria: (1) the potential water depth per house, (2) the distance between the dike and the house, (3) the architectural typology and (4) the closeness to rescue point. The methodological background and the first results for three towns are presented in this paper. Limitations and further developments are also discussed. [ABSTRACT FROM AUTHOR]

Storm Xynthia occurred on 28 February 2010. It was one of the most destructive climatic events to hit metropolitan France for several decades, causing 47 victims in France, among whom more than half died in the department of Vendée. The occurence of various natural phenomena (atmospheric pressure, strength and orientation of the wind, tidal range) at the same time caused a major coastal flood in several urban areas from Vendée and Charente-Maritime (central Atlantic region of France). The evaluation of the disaster highlighted a number of problems, especially delays in approving the PPR-L ( Plan de Prévention des Risques Littoraux) that allowed urbanization in the coastal flood plain that exposed population to major natural risks, such as sea level rise and floods. Since 28th February, 2010, the French government has focused on these issues and tried to define in a more accurate way the criteria used for the flood zonings of the PPR-L. A number of circulars and recommendations have been produced and they all specified rules of protection for properties against the risk of flood and the necessary measures for adapting or building current or future houses (e.g. height of the upper floor, presence of an upper floor refuge) in accordance with the level of risk. The objective of this paper is twofold: we wish to highlight the impact of the disaster Xynthia on the production of PPR-L in the short and medium terms while focusing on the example of the town of La-Faute-sur-Mer. We will also analyze the evolution of the regulations since 28 February 2010, with special attention paid to the proposed criteria to define the hazard. [ABSTRACT FROM AUTHOR]

A first application of geomorphological methods to the assessment of sandstone deterioration at Angkor is presented. Damage diagnosis was carried out on the first eastern tier of the central pyramid of the 1,000 year-old Ta Keo temple. Methods combine field observations and measurements at 230 sampling points, high-resolution lasergrammetry and stereophotogrammetry on a 2-m2 test zone, and SEM observations. The first results indicate that decay operates through a synergistic combination of weathering phenomena dominated by scaling and solution, and exhibits a high spatial variability. Percentages of deteriorated surfaces vary from 17.6 to 93.8%, and average stone recession values from 0.00 to 2.71 cm (minimum) and 0.34 to 5.49 cm (maximum). On the test-zone, stereophotogrammetry and 3D-mapping of the present and reconstructed initial states using lasergrammetry indicate that erosion scars up to 6 cm deep have formed since 1963. On the whole, the amount of deteriorated surfaces more than tripled between 1963 and 2008. The degree of implication of salts in stone decay remains unclear for most efflorescences are composed of calcite (CaCO3), with secondary importance of barite (BaSO4) and gypsum (CaSO4·2H2O). Future prospects aim to evaluate the impact on stone decay of the clearing out of the temple from the forest in the 1920s. [ABSTRACT FROM AUTHOR]

Background: This study analyzes individuals’ perceptions of areas exposed to coastal flooding at a local level using sketch mapping methodology. In this way, 318 individuals were surveyed in four coastal municipalities in France (Barneville-Carteret, Saintes-Maries-de-la-mer, Châtelaillon-Plage and Sainte-Anne). We assessed the disagreement between expert estimates and individuals’ perceptions of areas exposed to coastal flooding using sketch mapping indicators. We also determined the relationships between individuals’ living environments and the way they perceived the spatial extent of coastal flooding.Results: Respondents were likely to under-assess the exposure of areas that are actually exposed according to expert hazard maps. Perceived distance to coastal flooding areas appeared to be a predominant factor in assessing individuals’ perceptions.Conclusions: Local preventive actions could take into account the individuals’ tendency to under-estimate the areas exposed to coastal flooding. Individual perception of the spatial extent of coastal flooding appeared to be more influenced by the perceived distance of the home to exposed areas than the objective distance. It is a result that raises the question about the individuals’ understanding of hazard maps and regulatory maps. This may necessitate the improvement of the appropriation of these documents by the inhabitants by involving them more closely in the application and decision process that directly concerns. [ABSTRACT FROM AUTHOR]