50,322 research outputs found
Remind Solution (Australia) Brain Booster Benefits!
No full textHenceforth, the audit here has the intense Remind Solution, which is exceptional and helps upgrade your memory, in contrast to other memory items. Peruse the survey about Remind Solution, which could assist Remind Solution you with reestablishing your blissful and most important recollections throughout everyday life
The numerical solution of waveguide discontinuity problems
No full textA computational method for solving a wide range of transverse and longitudinal waveguide discontinuity problems is described. Results are obtained by the simultaneous solution of matrix equations, generated by Fourier analysis, which relate the complex amplitudes of orthogonal electric and magnetic field components. In some cases the solution is found to be sensitive to the way in
which infinite series of field functions are truncated, and it is shown how the optimum form of truncation can be determined for many configurations of practical importance.
Several examples showing the application of the method are
given, and comparison of results with those obtained by experiment, and by other analytical techniques, confirms its accuracy.
The application of the method in the design of discontinuities for higher-mode generation in multimode antennas is considered, particularly in connection with a multimode monopulse feed for a satellite-communication reflector antenna. Primary and secondary characteristics are determined theoretically for various modeconverter
configurations, allowing those giving satisfactory allround
performance to be selected. Comparison with conventional
feeds shows the multimode feed to be superior in many respects. A prototype multimode feed is constructed, and theoretical primary radiation patterns are compared with those obtained experimentally
Analytical solution for the cumulative wake of yawed wind turbines
No full textThis thesis sets out to improve the physical grounding and predictive accuracy of cumulative wake effect modelling within wind farms with yawed turbines. It derives an analytical solution for the lateral velocity field within a wind farm and compares its predictions to those of computational fluid dynamics.A parametric study is performed using a Reynolds-averaged Navier-Stokes (RANS) solver with the k-ε-fP turbulence model, Joukowsky rotor-based actuator disc, and neutral log-law inflow within the PyWakeEllipSys framework to determine the effects of yaw angle, thrust coefficient, and turbulence intensity on the lateral wake.The results of this parametric study are used to solve an approximate form of conservation of mass and momentum in the lateral direction for a turbine within a wind farm. The solution is an explicit equation predicting the lateral velocity distribution and lateral wake deflection within a wind farm of arbitrary layout and with arbitrarily yawed turbines. It also provides a first mathematical proof of secondary wake steering. The solution is implemented in Python and used to predict the velocity distributions in several wind farm cases, including for a single turbine, a two-turbine arrangement, and two wind farm cases with aligned and staggered layouts. These predictions are then compared against those of the RANS setup. The model significantly overestimates wake deflections unless corrected to neglect the near wake, but the corrected version shows promise, particularly in predicting wind farm power of the staggered layout, where the prediction is 19% closer to the RANS result than the prediction that considers lateral velocities equal to zero.https://github.com/NilsGaukroger/Analytical-solution-for-the-cumulative-wake-of-yawed-wind-turbinesEuropean Wind Energy Masters (EWEM) | Rotor Design Trac
Calculations of Freezing Point Depression, Boiling Point Elevation, Vapor Pressure and Enthalpies of Vaporization of Electrolyte Solutions by a Modified Three-Characteristic Parameter Correlation Model
No full textA method was proposed for calculating the thermodynamic properties, freezing point depression, boiling point elevation, vapor pressure and enthalpy of vaporization for single solute electrolyte solutions, including aqueous and nonaqueous solutions, based on a modified three-characteristic-parameter correlation model. When compared with the corresponding literature values, the calculated results show that this method gives a very good approximation, especially for 1-1 electrolytes. Although the method is not very suitable for some solutions with very high ionic strength, it is still a very useful technique when experimental data is scarce.Chemistry, PhysicalSCI(E)4ARTICLE91097-11173
Calculations of Freezing Point Depression, Boiling Point Elevation, Vapor Pressure and Enthalpies of Vaporization of Electrolyte Solutions by a Modified Three-Characteristic Parameter Correlation Model (vol 38, pg 1097, 2009)
No full textChemistry, PhysicalSCI(E)0CORRECTION4894-8954
The effect of nutrient solution conductivity on the growth of cucumber plants
No full textCucumber growth responses to nutrient solution conductivity (Ec) were evaluated. Four levels of nutrient solution Ec, ranging from 1.0 to 2.5 mS cm-I, were used. Plant height, stem diameter, leaf area and fresh and dry weight of different plant parts were measured. The results showed that cucumber plants can be grown in a wide range of nutrient solution Ec without affecting the plant growth and productivity. Plant water uptake and relative water content (RWC) were significantly reduced with increasing nutrient solution Ec. Plant water potential, measured 40 days after imposing the treatments, was higher for 2.5 mS cm-l than 1.0 mS cm-l plants. There was no significant effect for the treatments on the transpiration rate and stomatal conductance. Photosynthetic rate measured 40 days after applying the treatment, significantly increased with increasing nutrient solution Ec.Corresponding Author:
Dr. Abdulaziz R. Al-Harbi
Plant Production Department, College of Agriculture & Food Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia. Telephone:+96614678347, Fax:966-1-4678467
Email:[email protected]
The Twilight of “Chimerica”? China and the collapse of the American model
No full text“Chimerica” illustrates the interactions between a Chinese model of high savings, overinvestment and export-led growth and the American model of leverage investment, credit consumption and finance-led growth. The collapse of the U.S model, linked with the unregulated derivatives market, drives China to redirect its growth toward domestic consumption, despite the strengthening of regionalisation in East Asia. The new stimulus plan, based on investment, is limited by both income disparities and the under-development of social protection. Land reform, or the collective redistribution of the remaining state assets, could stimulate domestic consumption. But the first solution deprives the local state of financial resources, and the second solution collides with the interests of the state-party system. However, stronger social movements could lead to a better income distribution. Like two faces of the same coin, credit consumption or high savings rate reflect the crisis of a global accumulation regime, tailored for a financial oligarchy in the U.S, or for a party-state oligarchy in China.World Financial crisis, World Economic crisis, China, Usa
What makes an insight problem? The roles of heuristics, goal conception and solution recoding in knowledge-lean problems.
No full textFour experiments investigated transformation problems with insight characteristics. In Experiment 1, performance on a version of the 6-coin problem that had a concrete and visualizable solution followed a hill-climbing heuristic. Experiment 2 demonstrated that the difficulty of a version of the problem that potentially required insight for solution stems from the same hill-climbing heuristic, which creates an implicit conceptual block. Experiment 3 confirmed that the difficulty of the potential insight solution is conceptual, not procedural. Experiment 4 demonstrated the same principles of move selection on the 6-coin problem and the 10-coin (triangle) problem. It is argued that hill-climbing heuristics provide a common framework for understanding transformation and insight problem solving. Post-solution recoding may account for part of the phenomenology of insight
A Co-simulation Solution for Vehicle-Track Interaction Dynamics Problems
No full textA co-simulation solution based on direct equilibrium of contact forces is proposed to simulate vehicle-track interaction (VTI) dynamics. It is developed in two platforms, which presents an iterative feedback loop that exchanges contact force files and structure response field in real-time. The load vector acting on the structure is described by a moving Gaussian pulse, which approximates the Dirac-delta function. Through this approach, system matrices are not exported and the additional identification of the correspondence between structure nodes and vehicle positions is avoided, which is contrary to the typical scheme in existing co-simulation methods for VTI problems. The direct information exchange in the current solution simplifies the VTI model development, making it easier for the application in track design and maintenance phase. The solution is demonstrated by a general beam model subject to a quarter car and has been calibrated and verified by benchmark cases coded in MATLAB. The example presented is a baseline model for demonstration purposes. And the proposed scheme allows for flexibility in incorporating more complex structure configurations and vehicle motions for further study.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Integral Design & ManagementEngineering Structure
Application of the domain-integrated field relations method to the solution of large scale static and stationary magnetic field problems
No full textAuthor accepted manuscript of: “Application of the domain-integrated field relations method to the solution of large scale static and stationary magnetic field problems” IEEE Transactions on Magnetics, vol. 38, no. 2, pp. 465-468, Mar., 2002Electrical Engineering, Mathematics and Computer Scienc
- …
