59 research outputs found
Atmospheric Electricity Network: coupling with the Earth System, climate and biological systems
Sustainable Groundwater Management in the Arid Southwestern US: Coachella Valley, California
Sustainable groundwater management requires approaches to assess the influence of climate and management actions on the evolution of groundwater systems. Traditional approaches that apply continuity to assess groundwater sustainability fail to capture the spatial variability of aquifer responses. To address this gap, our study evaluates groundwater elevation data from the Coachella Valley, California, within a groundwater sustainability framework given the adoption of integrative management strategies in the valley. Our study details an innovative approach employing traditional statistical methods to improve understanding of aquifer responses. In this analysis, we evaluate trends at individual groundwater observation wells and regional groundwater behaviors using field significance. Regional elevation trends identified no significant trends during periods of intense groundwater replenishment, active since 1973, despite spatial variability in individual well trends. Our results illustrate the spatially limited effects of groundwater replenishment occur against a setting of long-term groundwater depletion, raising concerns over the definition of sustainable groundwater management in aquifer systems employing integrative management strategies
Long-term variation analysis of a tropical river’s annual streamflow regime over a 50-year period
Cosserat-Type Rods
In this chapter we discuss a Cosserat-type theory of rods. Cosserat-type rod theories are based on the consideration of a rod base curve as a deformable directed curve, that is a curve with attached deformable or non-deformable (rigid) vectors (directors), or based on the derivation of one-dimensional (1D) rod equations from the three-dimensional (3D) micropolar (Cosserat) continuum equations. In the literature are known theories of rods kinematics of which described by introduction of the translation vector and additionally p deformable directors or one deformable director or three unit orthogonal each other directors. The additional vector fields of directors describe the rotational (in some special cases additional) degrees of freedom of the rod. The aim of the chapter is to present a Cosserat-type theory of rods and to show various applications
On a thermodynamic theory of rods with two temperature fields
This paper presents a thermodynamic theory for elastic rods using the model of directed curves. In this model, the thin rod-like bodies are described as deformable curves with a triad of rigidly rotating vectors attached to each point. To account for the thermal effects in rods, we introduce two independent temperature fields: the absolute temperature field and the temperature deviation field. We present a complete derivation of the non-linear equations of thermoelastic rods, starting from the principles of thermodynamics. Finally, we prove the uniqueness of solution to the linearized equations of thermoelastodynamics for rods
Patterns of genetic variation in bud flushing of Abies alba populations
In the spring of 2007, 51 full-sib and six half-sib families of European silver fir were obtained through controlled and open pollinations from the same clones in a seed orchard. Genetic variation and parameters for bud flushing were determined in two progeny tests established in a nursery. The results indicate a high genetic control of bud flushing of European silver fir. Both the additive and the dominance genetic variances were major sources of genetic variation. The additive genetic variance was greater for open-pollinated than for full-sib progeny, representing 50-95% of phenotypic variance. Narrow-sense individual heritability estimates for control-pollinated progenies ranged from 0.14 to 0.64, while the full-sib family heritability ranged from 0.09 to 0.40. In the open-pollinated progenies, the values of individual and family heritability were higher than those in control-pollinated progeny and ranged from 0.50 to 0.95 for both. In both experiments, genetic parameters were higher for bud flushing at the beginning of the growing period than at later stages. The genetic correlations between bud phenology and growth traits were positive and significant in control-pollinated progeny but not significant in open-pollinated progeny. Positive significant correlations between control-pollinated and open-pollinated progeny showed a maternal effect. Bud flushing was negatively correlated with geographic and climatic parameters of the site of parents’ origin, accounting for 83-97% of the total variation of this adaptive trait
Deformation analysis of functionally graded beams by the direct approach
In this paper we employ the direct approach to the theory of rods and beams, which is based on the deformable curve model with a triad of rotating directors attached to each point. We show that this model (also called directed curve) is an efficient approach for analyzing the deformation of elastic beams with a complex material structure. Thus, we consider non-homogeneous, composite and functionally graded beams made of isotropic or orthotropic materials and we determine the effective stiffness properties in terms of the three-dimensional elasticity constants. We present general analytical expressions of the effective stiffness coefficients, valid for beams of arbitrary cross-section shape. Finally, we apply this method for FGM beams made of metal foams and compare our analytical results with the numerical results obtained by a finite element analysis
Modeling river-aquifer interaction and their ecological relevance in an alpine floodplain
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