Forecasting wind speed data by using a combination of ARIMA model with single exponential smoothing

Wind serves as natural resources as the solution to minimize global warming and has been commonly used to produce electricity. Because of their uncontrollable wind characteristics, wind speed forecasting is considered one of the best challenges in developing power generation. The Autoregressive Integrated Moving Average (ARIMA), Simple Exponential Smoothing (SES) and a hybrid model combination of ARIMA and SES will be used in this study to predict the wind speed. The mean absolute percentage error (MAPE) and the root mean square error (RMSE) are used as measurement of efficiency. The hybrid model provides a positive outcome for predicting wind speed compare to the single model of ARIMA and SES

Exploiting similarity in turbulent shear flows for turbulence modeling

It is well known that current k-epsilon models cannot predict the flow over a flat plate and its wake. In an effort to address this issue and other issues associated with turbulence closure, a new approach for turbulence modeling is proposed which exploits similarities in the flow field. Thus, if we consider the flow over a flat plate and its wake, then in addition to taking advantage of the log-law region, we can exploit the fact that the flow becomes self-similar in the far wake. This latter behavior makes it possible to cast the governing equations as a set of total differential equations. Solutions of this set and comparison with measured shear stress and velocity profiles yields the desired set of model constants. Such a set is, in general, different from other sets of model constants. The rational for such an approach is that if we can correctly model the flow over a flat plate and its far wake, then we can have a better chance of predicting the behavior in between. It is to be noted that the approach does not appeal, in any way, to the decay of homogeneous turbulence. This is because the asymptotic behavior of the flow under consideration is not representative of the decay of homogeneous turbulence

Synthesis and Evaluation of Some New Thiazoles as Antioxidant Additives for Egyptian Lubricating Oils

4-(2-Aminothiazol-4-yl)-phenol (1) reacted with 2-(4-methoxy-benzylidene)-malononitrile or 1,3-diphenyl-1H- pyrazole-4-carbaldehyde to afford enaminonitrile, pyrazolo derivatives 2 and 3, respectively. On the other hand, methylation of 1 afforded the acetyl derivative 4 which reacted with phenyl isothiocyanate, diazonium salt, acetic anhydride, cyclic anhydride, ethyl acetoacetate, benzaldehyde or phosphorous oxychloride to afford compounds 5-9, 11 and 12, respectively. Moreover, the compound 12 reacted with ethyl cyanoacetate to afford compound 13. A one-pot reaction of compound 1 with ethyl acetoacetate and benzaldehyde afforded compound 10. The synthesized compounds were evaluated as antioxidant additives for lube oil. Key words: Key words: Aminothiazole; Condensation; Antioxidant Additive

Population based optimization algorithms improvement using the predictive particles

A new efficient improvement, called Predictive Particle Modification (PPM), is proposed in this paper. This modification makes the particle look to the near area before moving toward the best solution of the group. This modification can be applied to any population algorithm. The basic philosophy of PPM is explained in detail. To evaluate the performance of PPM, it is applied to Particle Swarm Optimization (PSO) algorithm and Teaching Learning Based Optimization (TLBO) algorithm then tested using 23 standard benchmark functions. The effectiveness of these modifications are compared with the other unmodified population optimization algorithms based on the best solution, average solution, and convergence rate

Generalized optimal placement of PMUs considering power system observability, communication infrastructure, and quality of service requirements

This paper presents a generalized optimal placement of Phasor Measurement Units (PMUs) considering power system observability, reliability, Communication Infrastructure (CI), and latency time associated with this CI. Moreover, the economic study for additional new data transmission paths is considered as well as the availability of predefined locations of some PMUs and the preexisting communication devices (CDs) in some buses. Two cases for the location of the Control Center Base Station (CCBS) are considered; predefined case and free selected case. The PMUs placement and their required communication network topology and channel capacity are co-optimized simultaneously. In this study, two different approaches are applied to optimize the objective function; the first approach is combined from Binary Particle Swarm Optimization-Gravitational Search Algorithm (BPSOGSA) and the Minimum Spanning Tree (MST) algorithm, while the second approach is based only on BPSOGSA. The feasibility of the proposed approaches are examined by applying it to IEEE 14-bus and IEEE 118-bus systems

FACTS allocation considering loads uncertainty, steady state operation constraints, and dynamic operation constraints

This study proposes an algorithm to allocate different types of flexible AC transmission system (FACTS) in power systems. The main objective of this study is to maximize profit by minimizing the system’s operating cost including FACTS devices (FDs) installation cost. Dynamic and steady state operating restrictions with loads uncertainty are included in the problem formulation. The overall problem is solved using both teaching learning based optimization (TLBO) technique for attaining the optimal allocation of the FDs as main-optimization problem and matpower interior point solver (MIPS) for optimal power flow (OPF) as the sub-optimization problem. The validation of the proposed approach is verified by applying it to test system of 59-bus; Simplified 14-Generator model of the South East Australian power system

A study of frequency and pulses for stepper motor controller system by using programmable logic controller

The stepper motor movement process produced different frequency and pulses. This research explained about the frequency and pulses for the stepper motor movement by using Programmable Logic Controller (PLC) as research method. The study was done to find the suitable frequency and pulses for stepper motor movement by developing a prototype stepper motor controller system. The pulse frequency used did not affected the distance of moving load in the stepper motor operations. The increasing number of pulse frequency only will affect the time taken for the stepper motor to complete its operations. The result showed that number of pulse frequency at high operation was 5000 Hz. Pulse number reacted as a manipulated variable that affected both factor which is time taken of stepper motor operation and the distance of moving load

Effect of Different Growth Conditions on Certain Biochemical Parameters of Different Cyanobacterial Strains

Aims: Variation in the traditional growth medium conditions to enhance the production of lipids, carbohydrates, protein and the free amino acids content of three cyanobacterial species. Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.). Conclusion, significance and impact of study: Aerated enriched glucose medium (1%, w/v) was the best growth medium condition used in the present study

Microscopic description of Coulomb and nuclear excitation of multiphonon states in 40^{40}Ca + 40^{40}Ca collisions

We calculate the inelastic scattering cross sections to populate one- and two-phonon states in heavy ion collisions with both Coulomb and nuclear excitations. Starting from a microscopic approach based on RPA, we go beyond it in order to treat anharmonicities and non-linear terms in the exciting field. These anharmonicities and non-linearities are shown to have important effects on the cross sections both in the low energy part of the spectrum and in the energy region of the Double Giant Quadrupole Resonance. By properly introducing an optical potential the inelastic cross section is calculated semiclassically by integrating the excitation probability over all impact parameters. A satisfactory agreement with the experimental results is obtained.Comment: 20 pages, 2 figures, revtex, to be published in Phys. Rev.

String/(D−5)(D-5)-brane Duality and SS Duality as Symmetries of Actions

We realize the string/$(D-5)$-brane duality on the action level between the $T^{10-D}$-compactified heterotic string effective action and the $(D-5)$- brane effective action in $D$ dimensions by managing a Lagrange multiplier field. A dual dictionary is composed to be available for the translation between the elementary or solitonic solutions of the dual pair of actions. In the same way the $S$ duality is also reconstructed on the action level as a double dualization for the $T^6$-compactified heterotic string effective action.Comment: 9 pages, latex, no figure