194 research outputs found

    Pertumbuhan Dan Hasil Tanaman Tomat (Lycopersicum Esculentum Mill) Pada Berbagai Media Tumbuh Dengan Interval Penyiraman Air Kelapa Yang Berbeda

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    This research was carried out at the Green House Experimental Farm Science Park, Sigi Biromaru Sidondo sub-district, Sigi Regency, since April - July 2016. This research aims to determine the effect of different types of media is growing and the interval giving coconut water towards growth and yield of tomato plants with uses a Completely Randomized Design (CRD) two factors, where the first factor is the growing medium consisting of four levels treatments, M1 (medium soil and chicken manure), M2 (ground husk charcoal and media), M3 (medium soil and sawdust), M4 (medium soil and cow manure), and the second factor is the interval watering coconut water is P1 (4 days), P2 (8 days), and P3 (12 days). Each combination treatment was repeated three times so that there are 36 experimental units. The data were analyzed using analysis of variance, and the real effect then tested further using Honestly Significant Difference at 5% level. The results showed that the treatment M2P2 give very good influence on the growth phase of height with an average 121,67 cm at age 45 days after planting, the average number of leaves 268,67 strands, and the total dry weight of the average plant 204,67 g, whereas treatment M1P1 give very good influence on the amount of fruit on average of 7,67 with a total weight of ripe fruit average 243, 67 g and the average root volume 19,67 ml

    Single point modeling of rotating turbulent flows

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    A model for the effects of rotation on turbulence is proposed and tested. These effects which influence mainly the rate of turbulence decay are modeled in a modified turbulent energy dissipation rate equation that has explicit dependence on the mean rotation rate. An appropriate definition of the rotation rate derived from critical point theory and based on the invariants of the deformation tensor is proposed. The modeled dissipation rate equation is numerically well behaved and can be used in conjunction with any level of turbulence closure. The model is applied to the two-equation kappa-epsilon turbulence model and is used to compute separated flows in a backward-facing step and an axisymmetric swirling coaxial jets into a sudden expansion. In general, the rotation modified dissipation rate model shows some improvements over the standard kappa-epsilon model

    Alpha antagonists and intraoperative floppy iris syndrome: A spectrum

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    Sharif A Issa, Omar H Hadid, Oliver Baylis, Margaret DayanDepartment of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, UKBackground: To determine occurrence of features of intraoperative floppy iris syndrome (IFIS) during cataract surgery in patients taking systemic alpha-antagonists (AA).Methods: We prospectively studied patients on AA and who underwent phacoemulsification. The following were recorded: pupil diameter preoperatively, iris flaccidity, iris prolapse and peroperative miosis.Results: We studied 40 eyes of 31 subjects. Mean age was 78 years. Overall, 14 eyes (13 patients) showed signs of IFIS: 9/13 (69%) eyes of patients on tamsulosin, 1/18 (6%) eyes in the doxazosin group, 2/2 prazosin patients, 1/4 eyes in the indoramin group, and 1/2 eyes in two patients on a combination of doxazosin and tamsulosin. Most cases (92%) had only one or two signs of IFIS. Bilateral cataract surgery was undertaken in 9 patients but only one patient (on tamsulosin) had features of IFIS in both eyes, while 4 patients (2 on tamsulosin and 2 on other AA) showed signs of IFIS in one eye only, and 4 patients did not show IFIS in either eye.Conclusion: Most AA were associated with IFIS, but it tends to present as a spectrum of signs rather than full triad originally described. Tamsulosin was most likely to be associated with IFIS; however, its intake does not necessarily mean that IFIS will occur. For patients on AA, the behavior of the iris intraoperatively in one eye is a poor predictor of the other eye. Surgeons should anticipate the occurrence of IFIS in any patient on AA.Keywords: alpha blocker, alpha antagonist, cataract surgery, intraoperative floppy iris syndrome, tamsulosin

    Multidisciplinary Approach to Aerospike Nozzle Design

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    A model of a linear aerospike rocket nozzle that consists of coupled aerodynamic and structural analyses has been developed. A nonlinear computational fluid dynamics code is used to calculate the aerodynamic thrust, and a three-dimensional finite-element model is used to determine the structural response and weight. The model will be used to demonstrate multidisciplinary design optimization (MDO) capabilities for relevant engine concepts, assess performance of various MDO approaches, and provide a guide for future application development. In this study, the MDO problem is formulated using the multidisciplinary feasible (MDF) strategy. The results for the MDF formulation are presented with comparisons against separate aerodynamic and structural optimized designs. Significant improvements are demonstrated by using a multidisciplinary approach in comparison with the single-discipline design strategy

    Overview of turbulence model development and applications at Rocketdyne

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    This viewgraph presentation discusses turbulence modeling requirements, development philosophy, and approach; two major areas of concentration (high speed and low speed turbulence modeling); high speed turbulence modeling; compressibility effects; turbulence models adapted to USA code; M = 9.2 flat plate flow; Mach 7.05 flow over axisymmetric flare; Mach 8.6 flow over cold wall edge; low speed turbulence modeling; turbulence models being assessed; turbulence model deck structure and integration with Navier-Stokes solver; nonlinear algebraic-stress model; rotation modified k-epsilon model; and Reynolds stress model

    Three-dimensional free convection in molten gallium

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    Plasma Transport in Saturn's Low‐Latitude Ionosphere: Cassini Data

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    An edited version of this paper was published by AGU. Copyright 2019 American Geophysical Union.In 2017 the Cassini Orbiter made the first in situ measurements of the upper atmosphere and ionosphere of Saturn. The Ion and Neutral Mass Spectrometer in its ion mode measured densities of light ion species (H+, H2+, H3+, and He+), and the Radio and Plasma Wave Science instrument measured electron densities. During proximal orbit 287 (denoted P287), Cassini reached down to an altitude of about 3,000 km above the 1 bar atmospheric pressure level. The topside ionosphere plasma densities measured for P287 were consistent with ionospheric measurements during other proximal orbits. Spacecraft potentials were measured by the Radio and Plasma Wave Science Langmuir probe and are typically about negative 0.3 V. Also, for this one orbit, Ion and Neutral Mass Spectrometer was operated in an instrument mode allowing the energies of incident H+ ions to be measured. H+ is the major ion species in the topside ionosphere. Ion flow speeds relative to Saturn's atmosphere were determined. In the southern hemisphere, including near closest approach, the measured ion speeds were close to zero relative to Saturn's corotating atmosphere, but for northern latitudes, southward ion flow of about 3 km/s was observed. One possible interpretation is that the ring shadowing of the southern hemisphere sets up an interhemispheric plasma pressure gradient driving this flow

    Electron Density Distributions in Saturn's Ionosphere

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    This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Between 26 April and 15 September 2017, Cassini executed 23 highly inclined Grand Finale orbits through a new frontier for space exploration, the narrow region between Saturn and the D Ring, providing the first opportunity for obtaining in situ ionospheric measurements. During the Grand Finale orbits, the Radio and Plasma Wave Science instrument observed broadband whistler mode emissions and narrowband upper hybrid frequency emissions. Using known wave propagation characteristics of these two plasma wave modes, the electron density is derived over a broad range of ionospheric latitudes and altitudes. A two‐part exponential scale height model is fitted to the electron density measurements. The model yields a double‐layered ionosphere with plasma scale heights of 545/575 km for the northern/southern hemispheres below 4,500 km and plasma scale heights of 4,780/2,360 km for the northern/southern hemispheres above 4,500 km. The interpretation of these layers involves the interaction between the rings and the ionosphere
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