1,787 research outputs found

    Fourier transforms of Lipschitz functions on certain Lie groups

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    We study the order of magnitude of the Fourier transforms of certain Lipschitz functions on the special linear group of real matrices of order two

    A piecewise-linear reduced-order model of squeeze-film damping for deformable structures including large displacement effects

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    This paper presents a reduced-order model for the Reynolds equation for deformable structure and large displacements. It is based on the model established in [11] which is piece-wise linearized using two different methods. The advantages and drawbacks of each method are pointed out. The pull-in time of a microswitch is determined and compared to experimental and other simulation data.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838

    SOME OBSERVATIONS ON FISHES AND THEIR PARASITES OF DARBANDIKHAN LAKE, KURDISTAN REGION IN NORTH IRAQ

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    A total of 255 freshwater fishes, belonging to 17 species, namely: Barbus barbulus, B. grypus, Capoeta trutta, Capoeta umbla, Carasobarbus luteus, Carassius auratus, Chondrostoma regium, Cyprinion macrostomum, Cyprinus carpio, Garra rufa, Hemiculter leucisculus, Hypophthalmichthys molitrix, Luciobarbus esocinus, Squalius lepidus (Family Cyprinidae), Mystus pelusius (Bagridae), Silurus triostegus (Siluridae) and Mastacembelus mastacembelus (Mastacembelidae), were collected from Darbandikhan Lake, southeast of Sulaimani city, Kurdistan region, Iraq, from March 2012 to the end of October 2012. The fishes were examined for ectoparasites and endoparasites. The study revealed the existence of 45 species of parasites including: seven species of protozoans, 29 species of monogeneans, two species of trematodes, one species each of cestode and nematode, two species of acanthocephalans and three species of crustaceans. The present study revealed that Dactylogyrus suchengtaii and D. carassobarbi were the most parasites prevalent (100% and 90.90%, respectively) in the lake, while Scyphidia arctica was scarce (1.44%). The fish C. trutta was highly infected with parasites (nine species), followed by S. lepidus (eight species) and both C. luteus and M. mastacembelus (six species each), while G. rufa and H. molitrix were less infected (one species each). The ciliated protozoan Ichthyophthirius multifiliis was recorded on seven species of fishes with prevalence ranged between 2.89% and 23.52%, followed by the crustacean Lernaea cyprinacea which was recorded on four species of fishes (5% - 27.27%)

    SOME OBSERVATIONS ON FISHES AND THEIR PARASITES OF DARBANDIKHAN LAKE, KURDISTAN REGION IN NORTH IRAQ

    Get PDF
    A total of 255 freshwater fishes, belonging to 17 species, namely: Barbus barbulus, B. grypus, Capoeta trutta, Capoeta umbla, Carasobarbus luteus, Carassius auratus, Chondrostoma regium, Cyprinion macrostomum, Cyprinus carpio, Garra rufa, Hemiculter leucisculus, Hypophthalmichthys molitrix, Luciobarbus esocinus, Squalius lepidus (Family Cyprinidae), Mystus pelusius (Bagridae), Silurus triostegus (Siluridae) and Mastacembelus mastacembelus (Mastacembelidae), were collected from Darbandikhan Lake, southeast of Sulaimani city, Kurdistan region, Iraq, from March 2012 to the end of October 2012. The fishes were examined for ectoparasites and endoparasites. The study revealed the existence of 45 species of parasites including: seven species of protozoans, 29 species of monogeneans, two species of trematodes, one species each of cestode and nematode, two species of acanthocephalans and three species of crustaceans. The present study revealed that Dactylogyrus suchengtaii and D. carassobarbi were the most parasites prevalent (100% and 90.90%, respectively) in the lake, while Scyphidia arctica was scarce (1.44%). The fish C. trutta was highly infected with parasites (nine species), followed by S. lepidus (eight species) and both C. luteus and M. mastacembelus (six species each), while G. rufa and H. molitrix were less infected (one species each). The ciliated protozoan Ichthyophthirius multifiliis was recorded on seven species of fishes with prevalence ranged between 2.89% and 23.52%, followed by the crustacean Lernaea cyprinacea which was recorded on four species of fishes (5% - 27.27%)

    Dosis de azufre y tiempos de aplicación en el rendimiento y la calidad del aceite de canola cultivada en suelo calcáreo

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    Pakistan has been constantly deficient in its oil seed production and it is very difficult to meet the edible oil requirement of its ever-increasing population. A field experiment was conducted at the Agronomy Research Farm, The University of Agriculture Peshawar, Northern Pakistan during winter (2013–14). Five sulphur levels (15, 30, 45, 60 and 75 kg·ha-1) and times of application (at seedling, bolting and flowering stages) were used for the canola variety Abasin-95. The experiment was laid out in a randomized complete block design replicated four times on a 5 m × 3.2 m plot size. The results showed that the sulphur-applied plots gave the highest seed yield, biological yield, glucosinolate, erucic acid, oil content, protein content, oleic acid and linoleic acid compared to the control plots. Sulphur applied at the rate of 60 kg·ha-1 and applied at the bolting stage increased seed yield, biological yield, oil content, and protein content.Pakistán ha sido constante y crónicamente deficiente en producción de semillas oleaginosas y es muy difícil cumplir con la demanda de aceites comestibles para una población cada vez mayor. Se realizó un experimento de campo en la granja de investigación agronómica de la Universidad de Agricultura Peshawar, en el norte de Pakistán, durante el invierno (2013–14). Los cinco niveles de azufre (15, 30, 45, 60 y 75 kg·ha-1) y su tiempo de aplicación (en las etapas de plántula, floración y floración) se utilizaron para la variedad de canola (Abasin-95). El experimento se realizó en un diseño de bloques completos al azar que se replicó cuatro veces con un tamaño de parcela de 5 m × 3,2 m. Los resultados mostraron que las parcelas aplicadas con azufre dieron el mayor rendimiento de semilla, rendimiento biológico, glucosinolato, ácido erúcico, contenido de aceite, contenido de proteína, ácido oleico y ácido linoleico en comparación con las parcelas de control. El azufre se aplicó en una tasa de 60 kg·ha-1 y se aplicó en la etapa de empernado, incrementando el rendimiento de las semillas, el rendimiento biológico, el contenido de aceite y el contenido de proteínas

    The Effect of Time-Delay Feedback Controller on an Electrically Actuated Resonator

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    This paper presents a study of the effect of a time-delay feedback controller on the dynamics of a Microelectromechanical systems (MEMS) capacitor actuated by DC and AC voltages. It is shown that negative time-delay feedback control gain can lead to an unstable system, even if AC voltage is relatively small compared to DC voltage. Perturbation method is utilized to present analytically the nonlinear dynamic characteristics of the MEMS capacitor. Agreements among the results of a shooting technique, long-time integration, basin of attraction analysis with the perturbation method are achieved

    The Fourier transforms of Lipschitz functions on the Heisenberg group

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    We study the order of magnitude of the Fourier transforms of certain Lipschitz functions on the Heisenberg group Hn. We compare our conclusions with some previous results in the field

    Trapping cold atoms using surface-grown carbon nanotubes

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    We present a feasibility study for loading cold atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimentally sustainable nanotube currents, generating trapped clouds whose densities and lifetimes are sufficient to enable detection by simple imaging methods. This opens the way for a novel type of conductor to be used in atomchips, enabling atom trapping at sub-micron distances, with implications for both fundamental studies and for technological applications

    Effect of tannery effluents on seed germination and growth of two sunflower cultivars

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    The wastewater of a tannery in Multan, Pakistan, was alkaline with high biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values along with much higher concentrations of total settle able salts and suspended solids, sodium adsorption ratio and high amount of sodium having the water quality class C3S1. Effluent was examined for its chemical constituents and the effect of its various dilutions was examined in greenhouse on two newly recommended sunflower cultivars (FH-330 and FH- 245) during their whole growth period. Percentage of germination, chlorophyll, carbohydrates and protein contents of both the sunflower cultivars showed significant (p = 0.05) decreasing trend with increasing effluent concentrations. Vegetative growth parameters like plant height and number of leaves per plant were significantly (p = 0.05) reduced with the increasing levels of effluents. Rate of leaf senescence of both cultivars was higher under higher effluent concentrations. Yield of sunflower crop in both cultivars was significantly (p = 0.05) reduced due to effluent concentrations. Seeds per capitulum were decreased to 49%, seeds weight per plant to 61 - 66% and 100-seed weight to 49 - 59%. The appearance of pale yellowish color of the affected plants was due to reduction in photosynthetic material under higher effluent concentration. Full strength effluent concentration caused the reduction in biomass accumulation and reproductive growth of sunflower cultivars. The results revealed that cultivar FH-330 was relatively resistant to varying effluent concentrations as compared to the cultivar FH- 245. However, the tannery effluents due to the presence of chemicals are not suitable for inclusion in irrigation system.Key words: Tannery effluents, sunflower, seed germination, growth, adverse effect, reduced yield
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