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The monitoring of dams provides a series of chronological measurements from different devices installed in the structure. These measurements must be analyzed in order to determine the behavior of the dam with respect to the factors (hydrostatic pressure, temperature, aging, etc.) influencing its stability. The work presented in this article, concerns the analysis of a set of pendular measurements (280 measurements approximately), spread over a period of 16 years (from September 1, 2003 to September 30, 2019), of the Beni-Haroun dam (Wilaya of Mila-Algeria) using the HST model (Hydrostatic, Seasonal, Temporal). The application of the HST model on these measurements allowed to quantify the displacements relative to the effects (hydrostatic, seasonal and time) on the one hand and to separate the reversible effects (hydrostatic and seasonal effects) from the irreversible effect (time) by the calculation of the corrected displacements on the other hand. The displacements due to the hydrostatic effect are more important (up to 14 mm) than those due to the other effects (not exceeding 5 mm). In order to make a judgment on the behavior of the dam, interpretation indicators were calculated for each effect. The values obtained are insignificant (of the order of a thousandth), which means that none of the three effects presents a risk for the stability of the structure (indicators below unity). [ABSTRACT FROM AUTHOR]

Understanding how ducks use breeding habitat can help managers ensure conservation efforts are focused on the types, locations, and connectivity of habitat species require. Recent technological advancements have provided high temporal and spatial resolution on animal movements, revealing unexpected patterns in movement and habitat use. As part of a larger study, we attached a GPS-GSM backpack transmitter to a second-year female Mallard (Anas platyrhynchos) captured in a decoy trap on 28 April 2018 in Alberta, Canada's boreal forest. Following marking, we qualitatively inferred from the duck's movement path that she made at least one nesting attempt; however, we were unable to confirm a nest location. Approximately 30 d after marking, the duck made a long-distance (>200 km) movement west-southwest into the boreal transition zone and then proceeded to make another long-distance movement southeast (>450 km) into the prairie potholes region, where we suspected she made at least one more nesting attempt in early July based on clustered GPS data. After spending just over 30 d in a localized prairie potholes region (all points within ∼1 km radius), she began moving north in early August and by the end of the month had returned to within 4 km of where she was originally marked, and to the same boreal wetland where she first attempted to nest. Overall, the female Mallard traveled >1,000 km within the breeding period and used habitats in 2 disparate biomes for presumed nesting, the prairie potholes and the boreal forest. Herein we provide additional details about our observation and propose some hypotheses to explain the phenomenon. [ABSTRACT FROM AUTHOR]

Using the finite element method, the present study deals first, with the behavior of a cracked structure repaired and not repaired by a patch, then the interaction effect between two surface cracks moving in opposite directions. The stress intensity factors (SIFs) and adhesive stresses will be estimated; the transverse and longitudinal displacements of a crack for an invariable length will be studied, as well as the effect of a crack oriented on a plane inclined with respect to the main crack. The results obtained clearly indicate that the interaction effect is decisive when these cracks are very close to each other. In this case, the distribution of shear stresses in the adhesive layer along the virtual line is also analyzed using the finite element method. [ABSTRACT FROM AUTHOR]

Women face particular travel challenges when combining commuting with broader caring responsibilities. This policy note considers the issues associated with meeting the transport needs of working women as they navigate their daily ‘mobilities of care’. We extend the concept of ‘mobilities of care’ by combining an intersectional understanding of the transport task with the principles embodied in the child-friendly cities agenda. These are discussed with respect to the provision of public transport services and infrastructure in Australia to illuminate the ways that such an approach could deliver transport benefits to those commuting with young children in their care, most often mothers. We also argue that transport policy, planning and provision must make an explicit connection between intersectional factors such as disability, class, as well as gender, and the substantive impact they can have on women and children’s mobilities and modal choices. [ABSTRACT FROM PUBLISHER]

Backfilling of mine stopes helps provide a safe workplace underground. The interaction between the backfill and surrounding rock mass has to be evaluated to ensure the secure application of backfill. This critical issue has led to much research on the stress state in single (isolated) backfilled stopes. However, the stress distribution in multiple openings that interact with each other has not yet been investigated as thoroughly. In this paper, the authors are using numerical simulations to evaluate the response of two adjacent backfilled stopes created in sequence, with a new assumption that is based on an explicit relationship between Pois son's ratio and the internal friction angle of the backfill; as shown here, the use of this relationship can significantly modify the stress state in backfilled stopes. The simulation results, presented in terms of stresses, displacements, and strains, illustrate the influence of different parameters including backfill strength, pillar width, stope depth, rock mass stiffness, natural stress state, and excavation and filling sequence. Complementary aspects are also considered. A discussion follows on some of the characteristics and limitations of this investigation. [ABSTRACT FROM AUTHOR]

Solitary, facultative migrating animals must make decisions each year on whether, when, and where to migrate. Factors influencing individuals in their movement choices are poorly understood. American black bears ( Ursus americanus Pallas, 1780) commonly migrate in late summer to areas of concentrated foods before winter denning; some bears also move long distances to dens. We radio-tracked seasonal migrations of >200 bears in Minnesota, USA, over 10 years. We observed concurrences in movements that suggested social coordination among individuals, including ( i) individuals with neighboring summer ranges traveling to the same distant feeding and (or) denning areas, ( ii) shared travel routes with use staggered through time, and ( iii) instances of ≥2 individuals traveling in loose tandem over tens of kilometres. We sought to explain the mechanism for these coordinated migrations by comparing our observations to the predictions of six hypotheses: instinct, landscape morphology, habitat gradients, long-distance olfaction, maternal teaching, and conspecific cueing. The most parsimonious explanation was that bears follow other bears, with social cueing likely mediated through chemical communication. Males likely play a key role in social transmission of knowledge of the nutritional landscape via a system of travel routes and information centers that benefits the entire population. [ABSTRACT FROM AUTHOR]

Although activity budget, movements, and habitat use of herbivores have been extensively studied, few studies have simultaneously examined these behaviors at several temporal scales. We investigated the influence of spatiotemporal variations in forage and climate on the activity and movement patterns of white-tailed deer ( Odocoileus virginianus (Zimmermann, 1780)) at high density, in a predator-free ecosystem impacted by long-term browsing. We used GPS telemetry and activity sensors to monitor seasonal activity budgets, movements, and patterns of habitat use within the home ranges of 24 female deer at three temporal scales: (1) season, (2) within season, and (3) daily. At large temporal scale, deer were less active and moved less during winter than during summer. Within each season, deer reduced their activity and movements in areas where forage resources were abundant and when climatic conditions were more difficult. On a daily scale, summer and winter movements peaked at dusk, but habitat selection neither changed with period of the day nor activity (foraging vs. resting). These results provide empirical evidence on how environmental constraints can modulate the trade-offs between forage acquisition and exposure to limiting factors. [ABSTRACT FROM AUTHOR]

For most Australian parents, there is continuing tension between work and family commitments. This tension is exacerbated by the need not only to have sufficient time available to children in the family but also for that time to be characterized by nurturance and guidance. This article reports on a qualitative study that explored how 21 part-time or full-time working parents, who also commute 10–15 hours a week to work, manage both the quantity and quality of their time with their young children (0–5 years). The study revealed the difficult conditions of commuting and the importance of social support to parents' well-being, as well as a significant pattern of parent–child interaction which we have described as ‘attentive parenting.’ Parents felt these activities contributed to the parent–child bond and their children's well-being in spite of an acknowledged lack of interactive time. [ABSTRACT FROM AUTHOR]

As with other turtles, the postemergent movements, overwintering behaviours, and survivorship of hatchling Diamond-backed Terrapins ( Malaclemys terrapin (Schoepff, 1793)) are poorly known, but anecdotal reports suggest that they may spend more time on land than most aquatic turtles. We investigated this behaviour using drift fences with pitfall traps on the island of Ruler's Bar, Jamaica Bay, New York, fall 2006 to spring 2008. We captured 324 live hatchling Terrapins, 95 were recaptured at least once, and we found 43 dead. After emergence from nests in the fall, most hatchlings moved upland away from the water; this pattern was reversed in the spring. Hatchling body sizes shrank during winter, probably owing to desiccation, and hatchlings were more likely to move on warmer days and days without precipitation. We recaptured some hatchlings on land as long as 9 months after emergence. As a result, hatchling M. terrapin were seen on land from April to December, well outside fall and spring during which they emerge from nests, and we found strong evidence that hatchling M. terrapin overwinter on land outside their nests. One important nest predator (raccoons, Procyon lotor (L., 1758)) was also an important hatchling predator, as were Norway rats ( Rattus norvegicus (Berkenhout, 1769)). Future work should investigate the terrestrial microhabitats used by hatchling M. terrapin, and management should protect hatchlings during this life stage. [ABSTRACT FROM AUTHOR]

A common strategy for reptile conservation is to establish reserves around nesting or hibernation sites. The government of British Columbia, Canada, mandates protection of 200-300 ha wildlife habitat areas (WHAs) around hibernation sites of the federally threatened Great Basin Gophersnakes ( Stejneger, 1893), but practical constraints result in a mean size of 193 ha. To evaluate the efficacy of this reserve size, we radio-tracked 39 adult Gophersnakes at four study sites in the Okanagan Valley in 2006 and 2007. Home ranges averaged 10.5 ± 1.7 ha. The maximum distance traveled from a hibernation site was 2400 m, whereas the maximum distance dispersed averaged 520 ± 65 m. An idealized circular WHA of 193 ha with the hibernation site at the centre would be large enough to contain Gophersnake home ranges, but the dispersal data show that only 85% of snakes would stay within that area. Small or asymmetrical WHAs likely protect even fewer Gophersnake locations. We recommend that WHAs be expanded if possible because the high mobility of Gophersnakes suggests that current reserves may not offer adequate protection. [ABSTRACT FROM AUTHOR]

In this paper I provide evidence that suggests selective retirement does not bias estimates of wage losses due to displacement. I estimate the magnitude of hourly wage losses faced by workers who are displaced when over the age of 50. I account for the self-selection of older workers into retirement, which prevents observation of some workers' potential wage losses. The results confirm that high tenured older workers face large wage losses following displacement. [ABSTRACT FROM AUTHOR]

Abstract: A recent theorem giving the initial behavior of very short-time fluctuations of particle displacements in classical many-body systems is discussed. It has applications to equilibrium and non-equilibrium systems, one of which is a series expansion of the distribution of work fluctuations around a Gaussian function. To determine the time-scale at which this series expansion is valid, we present preliminary numerical results for a Lennard-Jones fluid. These results suggest that the series expansion is useful up to time scales on the order of a picosecond, below which a simple Gaussian function for the distribution of the displacements can be used. To cite this article: R. van Zon et al., C. R. Physique 8 (2007). [Copyright &y& Elsevier]

The March 1996 slope failure in a municipal solid waste landfill near Cincinnati, Ohio, USA, is reanalyzed using continuum-mechanics-based procedures implemented in the computer programs FLAC and FLAC3D. A failure mechanism, based on the field observations of the failure, is used for the analyses. The failure mechanism is also implemented in a limit-equilibrium-based slope stability analysis computer program, SSTAB2, to simulate the observed translational character of the failure. The reanalysis results (failure surface, factor-of-safety (FoS), and displacement) from the continuum models are in general agreement with the field data. The FoS values from SSTAB2, FLAC, and FLAC3D range in the expected order. Overall, the reanalysis results supplement previously reported failure analyses. This paper serves two functions: (1) it documents the results of reanalysis using a different (from the previously published) failure mechanism hypothesis for the 1996 landfill slope failure near Cincinnati, Ohio; and (2) it demonstrates the use of 2-D and 3-D continuum models to study: (i) onset of instability; (ii) failure surface geometry and location; and (iii) displacements associated with slope failures. [ABSTRACT FROM AUTHOR]

Abstract: The Middle Palaeolithic mineral environment in the South of the Massif Central: preliminary petroarchaeological results. Five Middle-Palaeolithic assemblages coming from archaeological sites in the Haute-Loire and Ardèche dated to isotopic stages 7 to 5 have been studied using a petroarchaeological method based on the optimization of observation techniques at different scales with respect to genetic and postgenetic characteristics of flint raw materials. The method reveals a relatively large collection area for the middle mountain sites (Sainte-Anne I, Baume-Vallée, Le Rond-de-Saint-Arcons, Rochelimagne), but apparently a smaller one for the site of Payre, located nearby the side of the Rhône Valley. For all sites, gathering is predominantly local, but some distant sources are utilised too. The rare exogenous materials, for example the Bedoulian flint from Ardèche identified in the Velay assemblages (Sainte-Anne I, Baume-Vallée) are in fact located in the heart of the massif as well as in secondary deposits and thus do not allow one to establish firm circulation routes for, or certain contact between the relevant human groups. To cite this article: P. Fernandes et al., C. R. Palevol 5 (2006) . [Copyright &y& Elsevier]

Wolves (Canis lupus) on the Canadian barrens are intimately linked to migrating herds of barren-ground caribou (Rangifer tarandus). We deployed a Global Positioning System (GPS) radio collar on an adult female wolf to record her movements in response to changing caribou densities near her den during summer. This wolf and two other females were observed nursing a group of 11 pups. She traveled a minimum of 341 km during a 14-day excursion. The straight-line distance from the den to the farthest location was 103 km, and the overall minimum rate of travel was 3.1 km/h. The distance between the wolf and the radio-collared caribou decreased from 242 km one week before the excursion to 8 km four days into the excursion. We discuss several possible explanations for the long foraging bout. [ABSTRACT FROM AUTHOR]

It is postulated that for purposes of seismic design, the ductile behaviour of lateral force-resisting wall components, elements, and indeed the entire system can be satisfactorily simulated by bilinear force–displacement modeling. This enables displacement relationships between the system and its constituent components at a particular limit state to be readily established. To this end, some widely used fallacies, relevant to the transition from the elastic to the plastic domain of behaviour, are exposed. A redefinition of stiffness and yield displacement allows more realistic predictions of the important feature of seismic response, component displacements, to be made. The concepts are rational, yet very simple. Their applications are interwoven with the designer's intentions. Contrary to current design practice, whereby a specific global displacement ductility capacity is prescribed for a particular structural class, the designer can determine the acceptable displacement demand to be imposed on the system. This should protect critical components against excessive displacements. Specific intended displacement demands and capacities of systems comprising reinforced concrete cantilever and coupled walls can be estimated.Key words: ductility, displacements, reinforced concrete, seismic design, stiffness, structural walls.Il est postulé que, pour la conception parasismique, le comportement ductile des composantes résistant aux forces latérales, les éléments et le système tout entier d'ailleurs, peut être simulé de façon satisfaisante par un modèle bi-linéraire force–déplacement. Ceci permet d'établir des relations entre le déplacement du système et ces composantes à un état limite particulier facilement établi. Cependant, plusieurs erreurs sont exposées au sujet de la transition entre le comportement du domaine élastique au domaine plastique. Une redéfinition de la rigidité et du déplacement permet des prédictions plus réalistes des traits importants de la réponse sismique, déplacement des composantes, à être fait. Les concepts sont logiques et très simples. Leurs applications sont entremêlées avec les intentions du concepteur. Contrairement aux pratiques de conception courantes, par lesquelles une capacité spécifique de déplacement ductile global est prescrite pour une classe structurale particulière, le concepteur peut déterminer le niveau de déplacement acceptable a être imposé au système. Ceci devrait protéger les composantes critiques contre des déplacements excessifs. Les demandes et les capacités de déplacements spécifiques voulus des systèmes comprenant des murs à porte-à-faux et couplés en béton armé peuvent être estimés.Mots clés : ductilité, déplacements, béton armé, conception parasismique, rigidité, murs structuraux.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Analysis of the time-dependent changes in displacements, internal forces, and reactions at the supports in continuous reinforced concrete structures cast, prestressed, and loaded at different stages is frequently needed in design to satisfy the serviceability requirements. The time-dependent parameters considered in the analysis are creep and shrinkage of concrete, relaxation of prestressed steel, sequence of construction, and changes in structural system and support conditions. A procedure of analysis is presented using conventional linear analysis computer programs. The analysis procedure is explained through examples to demonstrate its simplicity and applicability.Key words: analysis, computer program, creep, displacement, frames, precast concrete, prestressed concrete, relaxation, shrinkage, time-dependent.L'analyse des variations en fonction du temps des déplacements, des forces internes et des réactions aux supports dans des structures de béton armé continues coulées, précontraintes et chargées à différentes étapes est fréquemment requise lors de la conception afin de satisfaire les exigences d'utilisation. Les paramètres dépendants du temps considérés dans l'analyse sont le glissement et la contraction du béton, l'extension de l'acier précontraint, la séquence de construction, et les changements dans le système structural et les conditions de support. Une procédure d'analyse est présentée et utilise des programmes informatiques d'analyse linéaire conventionels. La procédure de l'analyse est expliquée par le biais d'exemples afin de démontrer sa simplicité et son applicabilité.Mots clés : analyse, programme informatique, glissement, déplacements, cadres, béton préfabriqué, béton précontraint, extension, contraction, fonction du temps.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]