Vortex sheets with reflection symmetry in exterior domains

AbstractIn this paper we prove the existence of a weak solution of the incompressible 2D Euler equations in the exterior of a reflection symmetric smooth bluff body with symmetric initial flow corresponding to vortex sheet type data whose vorticity is of distinguished sign on each side of the symmetry axis. This work extends the results proved for full plane flow by the authors in [M.C. Lopes Filho, H.J. Nussenzveig Lopes, Z. Xin, Existence of vortex sheets with reflection symmetry in two space dimensions, Arch. Ration. Mech. Anal. 158 (3) (2001) 235–257]

Evidence for partial rotation alignment in proton emitting 121Pr

Abstract Using nonadiabatic quasiparticle calculations we reproduce the experimental half-life for proton radioactivity in 121Pr assuming that the decaying state has angular momentum J π = 7 / 2 − , thus showing for the first time clear evidence for partial rotation alignment in a proton emitting nucleus. The treatment of the pairing interaction in the BCS approach produces profound changes in the ordering of energy levels, and at high deformation, the state 7 / 2 − coming from the h 11 / 2 spherical shell becomes the bandhead

Business Intelligence in the Vineyard

The evolution that is nowadays taking place in the information and communication fields, namely in mobile computing and remote monitoring, constitutes a very interesting challenge to the agricultural sector. This reality places agronomic knowledge in centre stage as these technologies are dramatically improving data collection and storage capacities, challenging the farmers and the agricultural field experts to develop processes that efficiently transform data into information and knowledge and are able to support the everyday decision making at farm level. In this work we will present a demonstration project under way in a vineyard in Portugal where we are exploring the potential of the most recent technological innovations available in the market to build the i-Farm, the information and knowledge society intelligent farm. i-Farm (intelligent farm) applies at farm level the potential offered by using in an integrated way mobile solutions, sensor networks, wireless communication and digital imagery materialized in a information system that supports farmer real time decision making in the field and in the office. The i-Farm project creates a unique knowledge repository containing information from multiple sources (crop, environment, soil, operations, market, etc.) enabling accurate and timely decisions. For the project development a Business Intelligence approach is used. In the context of this paper this broad term is used to refer to the process of aggregating, processing and building rich and relevant information which is made available dynamically in real time to managers in an interactive way to support decisions and planning activitiesinfo:eu-repo/semantics/publishedVersio

Design Concepts for Peel-Dominant Adhesive Joints in Aeronautic Applications

The adhesive bonding technique is employed from the aeronautical/aerospace industry to current house products. To comply with the requirements of distinct applications, different joint configurations are available to the designer. While single-lap joints (SLJ) are the most common in application and research, double-lap joints, scarf joints and T-joints find specific applications. T-joints are seldom studied in the literature, but these are used, for instance, in aircraft to bond the stiffener beams to the skin, or in the cars between the B-pillar and the rocker. Due to the high stress concentrations, T-joints often fail under average stresses much lower than the adhesive strengths, giving rise to the necessity for proper design and strength improvement methodologies. This work initially aims to validate the cohesive zone modelling (CZM) technique with experiments, and then use it to numerically evaluate and optimize the performance of T-joints subjected to peel loads. CZM is nowadays regarded as the most powerful strength prediction tool for adhesive joints, and can be a valuable tool to improve T-joints. Different features are addressed for a complete analysis: adhesive type, geometrical parameters, dual-adhesive technique for strength improvement, and composite joints. The evaluated geometrical parameters are the base adherend thickness (a), T-part thickness (t), overlap or bonding length (l) and curvature radius (r). As a result of this work, the model was successfully validated, and clear design guidelines were provided to define the ideal geometric and material (adhesive) conditions for best performance

Nonlinear stabilitty for steady vortex pairs

In this article, we prove nonlinear orbital stability for steadily translating vortex pairs, a family of nonlinear waves that are exact solutions of the incompressible, two-dimensional Euler equations. We use an adaptation of Kelvin's variational principle, maximizing kinetic energy penalised by a multiple of momentum among mirror-symmetric isovortical rearrangements. This formulation has the advantage that the functional to be maximized and the constraint set are both invariant under the flow of the time-dependent Euler equations, and this observation is used strongly in the analysis. Previous work on existence yields a wide class of examples to which our result applies.Comment: 25 page

An Extension Of Marchioro's Bound On The Growth Of A Vortex Patch To Flows With Lp Vorticity

We observe that C. Marchioro's cubic-root bound in time on the growth of the diameter of a patch of vorticity [Comm. Math. Phys, 164 (1994), pp. 507-524] can be extended to incompressible two-dimensional Euler flows with compactly supported initial vorticity in Lp, p > 2, and with a distinguished sign.293596599Delort, J.-M., Existence de nappes de tourbillons en dimension deux (1991) J. Amer. Math. Soc., 4, pp. 553-586Majda, A., Vorticity and the mathematical theory of incompressible fluid flow (1986) Comm. Pure Appl. Math., 39, pp. S187-S220Marchioro, C., Bounds on the growth of the support of a vortex patch (1994) Comm. Math. Phys., 164, pp. 507-524Schocket, S., The weak vorticity formulation of the 2D Euler equations and concentration-cancellation (1995) Comm. Partial Differential Equations, 20, pp. 1077-110

Composição esterólica e em ácidos gordos de azeites monovarietais provenientes das regiões de Elvas, Castelo Branco e Santarém

Comunicação apresentada no III Simpósio Nacional de Olivicultura que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 29 a 31 de Outubro de 2003.Neste trabalho apresenta-se um estudo efectuado em cinco azeites monovarietais (Olea europaea ‘Cordovil De Castelo Branco’, ‘Cobrançosa’, ‘Conserva De Elvas’, ‘Galega Vulgar’ e ‘Picual’). O estudo reporta-se a três campanhas consecutivas (2000/03) e o material experimental provém de olivais situados em três regiões portuguesas, nomeadamente Elvas, Castelo Branco e Santarém. Os azeites foram extraídos em equipamento Oliomio e as análises foram: ácidos gordos, esteróis e álcoois triterpénicos (eritrodiol + uvaol). Dos resultados obtidos, o azeite ‘Cordovil De Castelo Branco’ destaca-se pelos seus teores elevados em eritrodiol + uvaol nas três regiões em estudo. Por seu turno, o teor de ácido oleico do azeite ‘Galega Vulgar’ permite distinguir cada uma das regiões, enquanto no azeite ‘Cobrançosa’ o teor em esteróis totais distingue as três regiões

Evolução do teor de esteróis e alcoóis triterpénicos no envelhecimento de azeites monovarietais e loteados de seis cultivares no Norte Alentejano

Comunicação apresentada no III Simpósio Nacional de Olivicultura que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 29 a 31 de Outubro de 2003.A legislação europeia limita os teores de alguns esteróis no azeite virgem: valores máximos de colesterol, de brassicasterol, de campesterol, de estigmasterol e de ∆7-estigmastenol; e valores mínimos do β-sitosterol aparente e do total de esteróis. O presente trabalho mostra o efeito de um ano de envelhecimento – em frascos de vidro âmbar a 25 °C – nos teores destes esteróis em azeites monovarietais e loteados de seis cultivares no Norte Alentejano, da campanha de 2001/02. O envelhecimento foi geralmente acompanhado pelo aumento dos teores de β-sitosterol aparente, de ∆5-avenasterol e de esteróis totais e pela diminuição dos teores de campesterol e de estigmasterol

Is PCBs concentration variability between and within freshwater fish species explained by their contamination pathways?

Many chemical, physiological, and trophic factors are known to affect ioaccumulation of polychlorinated biphenyls (PCBs) in biota. Understanding the primary factors affecting fish contamination is critical for predicting and assessing risks to upper-trophic level consumers, including humans. Here we identify PCB contamination pathways that could explain within- and between-species variability in fish concentration levels. Three freshwater river fish species (barbel, chub and bream) were sampled at three sites along the Rhone River (France) where fish consumption is partially prohibited because of PCB levels exceeding the European health-based benchmark. The trophic position was assessed using an innovative approach based on stable isotope analyses and Bayesian inference, which takes into account both isotope data variability and parameter uncertainty. The effect of foraging habitat on fish contamination was addressed using stable isotope mixing models. The fish trophic position and PCB concentrations were found to be unrelated while the exploitation of sediment detrital carbon as a food source appeared to be a critical factor affecting fish contamination. Fish length, PCB concentration of the sediment, and individual fish foraging habitat (exploitation of detrital versus planktonic carbon sources) explained 80% of within- and between-species variability observed in PCB concentrations. These results, obtained for species that have overlapping TPs and exploit different carbon sources, reveal that the important factor in fish PCB contamination is not only what fish consume, but also and essentially the feeding location