1,818 research outputs found

    An electronic weather vane for field science

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    This paper details the construction of a weather vane for the measurement of wind direction in field situations. The purpose of its construction was to analyse how wind direction affected the attractiveness of an insect pheromone in a dynamic outdoor environment, where wind could be a significant contributor to odour movement. The apparatus described provides a cheap and easy-to-construct alternative to commercial wind vanes, and was shown to provide accurate and continuous measurement of wind direction

    Enhancing Seed Set and Seed Yield of Sewan Grass (\u3cem\u3eLasiurus sindicus\u3c/em\u3e) through Physiological Approaches

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    Western part of Rajasthan, the Thar desert, is the most thickly populated desert of the World, possessing more than 55 million population each of human and livestock. Aberrant weather conditions and poor soil fertility pose major threats to arable crops cultivation. Livestock rearing is directly dependent on fodder availability but due to harsh agro-climatic conditions there is severe fodder scarcity. Lasiurus sindicus, perennial grass grown in hot and warm grassland climate thrives well under moisture stress on sandy plains, low dunes and hummocks of this region, receiving annual rainfall below 200 mm. For decades, these grasslands in turn supported an ever increasing livestock population in the Indian desert. Establishment of this grass is hampered by low seed availability because of its poor seed yield due to poor seed set. While sufficient literature is available on forage productivity of Sewan grass, however, information on seed set and seed yield production is lacking

    The Search for Neutrino Oscillations numubar->nuebar with KARMEN

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    The neutrino experiment KARMEN is situated at the beam stop neutrino source ISIS. It provides numu's, nue's and numubar's in equal intensities from the pi+ mu+ decay at rest (DAR). The oscillation channel numub->nueb is investigated in the appearance mode with a 56t liquid scintillation calorimeter at a mean distance of 17.7m from the nu source looking for p(nue,e+)n reactions. The cosmic induced background for this oscillation search could be reduced by a factor of 40 due to an additional veto counter installed in 1996. In the data collected through 1997 and 1998 no potential oscillation event was observed. Using a unified approach to small signals this leads to an upper limit for the mixing angle of sin**2(2t) < 1.3x10^{-3} (90%CL) at large Dm**2. The excluded area in (sin**2(2t),Dm**2) covers almost entirely the favored region defined by the LSND numub->nueb evidence.Comment: Proceedings Contribution to Neutrino98 in Takayama, Japan, June 4-9, 1998; 13 pages, including 4 figure

    Quadratic Poisson brackets compatible with an algebra structure

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    Quadratic Poisson brackets on a vector space equipped with a bilinear multiplication are studied. A notion of a bracket compatible with the multiplication is introduced and an effective criterion of such compatibility is given. Among compatible brackets, a subclass of coboundary brackets is described, and such brackets are enumerated in a number of examples.Comment: 6 page

    A Cut Finite Element Method for the Bernoulli Free Boundary Value Problem

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    We develop a cut finite element method for the Bernoulli free boundary problem. The free boundary, represented by an approximate signed distance function on a fixed background mesh, is allowed to intersect elements in an arbitrary fashion. This leads to so called cut elements in the vicinity of the boundary. To obtain a stable method, stabilization terms is added in the vicinity of the cut elements penalizing the gradient jumps across element sides. The stabilization also ensures good conditioning of the resulting discrete system. We develop a method for shape optimization based on moving the distance function along a velocity field which is computed as the H1H^1 Riesz representation of the shape derivative. We show that the velocity field is the solution to an interface problem and we prove an a priori error estimate of optimal order, given the limited regularity of the velocity field across the interface, for the the velocity field in the H1H^1 norm. Finally, we present illustrating numerical results

    A Cut Finite Element Method for the Bernoulli Free Boundary Value Problem

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    We develop a cut finite element method for the Bernoulli free boundary problem. The free boundary, represented by an approximate signed distance function on a fixed background mesh, is allowed to intersect elements in an arbitrary fashion. This leads to so called cut elements in the vicinity of the boundary. To obtain a stable method, stabilization terms is added in the vicinity of the cut elements penalizing the gradient jumps across element sides. The stabilization also ensures good conditioning of the resulting discrete system. We develop a method for shape optimization based on moving the distance function along a velocity field which is computed as the H1H^1 Riesz representation of the shape derivative. We show that the velocity field is the solution to an interface problem and we prove an a priori error estimate of optimal order, given the limited regularity of the velocity field across the interface, for the the velocity field in the H1H^1 norm. Finally, we present illustrating numerical results

    A study of the Zygaenidae (Lepidoptera) fauna of Central Anatolia, Turkey

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    The Zygaenidae fauna in some provinces (Aksaray, Karaman, Kayseri, Konya, Nevşehir and Niğde) of Central Anatolia was studied using attractant traps as well as by netting specimens in biotopes in 2017. The sex attractants for the Procridinae had been produced in the Crimean Federal University and were esters of 2 dodecenoic acid and isomers of 2-butanol: EFETOV-2 [racemic mixture of R- and S-enantiomers], EFETOV-S-2 [R-enantiomer] and EFETOV-S-S-2 [S-enantiomer]. Zygaena attractants were made at Canterbury Christ Church University using a range of acetate compounds with known attraction to various genera as originally identified by Priesner et al. (1984). Fourteen Zygaenidae species from four genera belonging to Procridinae and Zygaeninae subfamilies were found: Rhagades Wallengren, 1863 (1 species), Adscita Retzius, 1783 (1 species), Jordanita Verity, 1946 (4 species), and Zygaena Fabricius, 1775 (8 species)
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