594 research outputs found
Design Broad Bandwidth Microwave Bandpass Filter Of 10 Ghz Operating Frequency Using HFSS
Microwave bandpass filter is the essential part in microwave circuits and wireless communication systems. This paper presents a new designing and simulation of broad bandwidth,low losses microwave bandpass filter operating at 10 GHz frequency using return loss method. The designing and simulation of the circuit has been carried out using Computer Aid Design (CAD) Ansoft HFSS software purchase from Ansys. The microwave filter circuit has designed with a parallel coupled line having a small dimension (10 Ă— 10 mm2) of LaAlO3 substrate. The microwave circuit showed a high return loss -20 dB, broad bandwidth of 1.5 GHz, and operating frequency at 10 GHz. The results indicate the filter design and simulation using HFSS is reliable and have the opportunity to transfer from lab potential experiments to industry
Locking-free two-layer Timoshenko beam element with interlayer slip
A new locking-free strain-based finite element formulation for the numerical treatment of linear static analysis of two-layer planar composite beams with interlayer slip is proposed. In this formulation, the modified principle of virtual work is introduced as a basis for the finite element discretization. The linear kinematic equations are included into the principle by the procedure, similar to that of Lagrangian multipliers. A strain field vector remains the only unknown function to be interpolated in the finite element implementation of the principle. In contrast with some of the displacement-based and mixed finite element formulations of the composite beams with interlayer slip, the present formulation is completely locking-free. Hence, there are no shear and slip locking, poor convergence and stress oscillations in these finite elements. The generalization of the composite beam theory with the consideration of the Timoshenko beam theory for the individual component of a composite beam represents a substantial contribution in the field of analysis of non-slender composite beams with an interlayer slip. An extension of the present formulation to the non-linear material problems is straightforward. As only a few finite elements are needed to describe a composite beam with great precision, the new finite element formulations is perfectly suited for practical calculations. (c) 2007 Elsevier B.V. All rights reserved
Adaptive Asymptotic Tracking of Spacecraft Attitude Motion with Inertia Matrix Identification
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57789/1/AhmedSCAdaptiveControlJGCD1998.pd
The Effect of Irrigation systems and Planting Methods on Soil Porosity and Soil Electrical Conductivity and Potato Yield sunder Two Irrigation Intervals
The experiment was conducted to evaluate the effect of irrigation systems, planting methods and irrigation intervals on soil porosity and soil electrical conductivity and potato yields for fall season of 2016 in Yousufia Area. Three irrigation systems included Sprinkler Irrigation (S), Drip irrigation (D),and Furrow Irrigation (F), two different irrigation intervals included (4 day irrigation interval (I1) and 8 day irrigation interval (I2)) and two methods of planting included (Mechanical planting (M) and Manual (Hand) planting (H) were used in the experiment. Soil Porosity, electrical conductivity of a saturated soil extract (Ece), average weight of potato tuber, and plant yield were measured in this study. Split split plots arrangment under Randomized Complete Block Design (RCBD) with three replicates, were used in this experiment. The means of treatments were compared by using least significant difference (LSD=0.05) under probability of 0.05.
The results can be summarized as follows:
1- Drip irrigation was superior in obtaining the least value of the electrical conductivity stood 2.76 ds.m-1, highest potato yield stood 811 gm. plantˉ¹ and highest value for the average weight of potato tuber was 150 gm. Also, the furrow irrigation treatment was superior in obtaining the highest value of soil porosity stood, 0.44 cm3.cm-3.
2- 4 days irrigation interval got a significant higher single plant yield stood 731 gm.plant-1, and potato tuber weight average stood 117.83 gm and got the least value of electrical conductivity stood 3.40 ds.m-1, whereas 8 days irrigation interval was superior in getting the highest value of porosity, stood 0.40 cm3.cm-3.
3- Mechanical planting method resulted in obtaining the highest value of porosity, stood 0.40 cm3.cm-3, and the highest yield for a single plant value stood 703 gm.plant-1, and the highest value of potato tuber average weight stood 131.33 gm.
4- The interaction between drip irrigation and 4 days irrigation interval was superior compared to other interactions in obtaining the least value of the electrical conductivity (Ece) stood 2.52 ds.m-1, and highest value of single plant yield stood 884 gm.plant-1, and highest value for the average weight of potato tuber stood 161.17 gm. On the other hand, the interaction between furrow irrigation method and the 8 days irrigation interval in obtaining the highest value for porosity which stood 0.44 cm3.cm-3.
5- The interaction between drip irrigation method and mechanical planting method was superior compared to other interactions in obtaining the highest yield value for single plant which stood 846 gm.plant-1, and the highest value for the weight average of potato tuber stood 157.50 gm. while, the interaction between furrow irrigation method and mechanical planting recorded the highest value for porosity which stood 0.46 cm3.cm-3.
6- The interaction between 4 days irrigation interval and mechanical planting showed a superiority in obtaining the highest value for single plant yield which stood 770 gm.plant-1, and highest value for the weight average for potato tuber stood 140.44 gm, compared to other interactions, and the interaction between 8days irrigation interval and mechanical planting method was superior to obtain the highest value of porosity stood 0.42 cm3.cm-3. Also, the interaction between 4 days irrigation interval and the manual (hand) planting methods was superior to obtain the least value for electrical conductivity for soil solution stood 3.34 ds.m-1.
7- The triple interaction between drip irrigation, 4 days irrigation interval, and mechanical planting method was superior in obtaining the highest yield for a single plant which stood 936 gm.plant-1 and the highest value of the weight average of potato tuber which stood 169.33 gm and the lowest value for electrical conductivity of soil solution which stood 2.50 ds.m-1 compared to other interactions. While the interaction between furrow irrigation method, 8 days irrigation interval, and mechanical planting method was superior to obtain the highest value of soil porosity stood 0.48 cm3.cm-3
Morphological structures and drug release effect of multiple electrospun nanofibre membrane systems based on PLA, PCL, and PCL/Magnetic nanoparticle composites
Biopolymers are good carrier materials in relation to efficient release sustainability for encapsulated drugs. In particular, electrospun polymer/composite fibre membranes can offer greater benefits owing to their competitive release features as well as large specific surface areas. In this study, multiple electrospun nanofibre membrane systems were utilised including different material systems such as poly(lactic acid) (PLA), poly(ε-caprolactone) (PCL), and PCL/magnetic nanoparticle (MP) composites loaded with tetracycline hydrochloride (TCH) as a therapeutic compound for their potential use in drug delivery applications. Such electrospun nanofibres were investigated to understand how composite constituents could tailor surface morphology for drug release control and biodegradation effect of PCL electrospun nanofibers on a long term for different drug release systems. Fibre diameter appeared to be decreased considerably with the addition of TCH drug. It was also evident that average fibre diameter was reduced when embedding MPs owing to the enhancement of solution conductivity. The encapsulation of TCH drug was found to be effective, as evidenced by Fourier transform infrared (FTIR) spectra. Thermogravimetric analysis (TGA) data revealed no significant change in the thermal stability of PCL with the inclusion of TCH and MPs. However, the use of TCH to PLA delayed the thermal degradation. Glass transition temperature (TQ) and melting temperature (TM) of PCL were decreased with the inclusion of MPs and TCH. The degree of crystallinity (XC) for PCL diminished when incorporated with MPs. Additional TCH to PLA, PCL, and PCL/MP nanocomposites resulted in a moderate decrease in (XC). TCH might be dispersed in an amorphous state within nanofibre membranes. Over the short-term periods, it was clearly seen that TCH release from PCL nanofibre membranes was higher as opposed to PLC/MP and PLA counterparts. On the contrary, such a drug release from PLC membranes became relatively slow owing to its high (XC). Further, the mass loss results were consistent with those obtained from in vitro drug release. Overall, TCH release kinetics of PCL/TCH nanofibre membranes were better estimated by Zeng model as opposed to PLA/TCH counterparts
Hydrodynamics and Kinetics of Phenols Removal from Industrial Wastewater in a Trickle Bed Reactor (Part I: Hydrodynamic Study)
An experimental investigation of the hydrodynamic parameters in a trickle bed reactor is presented. The operating conditions are selected for the operating system to be at trickle flow regime. The effects of the two-phase flow rates, reactor pressure and temperature
on the pressure drop, external liquid holdup and liquid axial dispersion are discussed. Pressure drop was measured using differential pressure transducer, while liquid holdup and axial dispersion were estimated using RTD technique with a reactive dye as
a tracer. The results confirmed that pressure drop is proportional to flow rate of fluids and operating pressure while it is inversely proportional to temperature. Liquid flow rate has a proportional effect on liquid holdup and axial dispersion while gas flow rate and temperature presented a different image. A comparison between the results of present work and that of literature is presented and discussed. Empirical correlations for pressure drop, liquid holdup and axial dispersion with operating conditions are developed with correlation coefficient of 98.4 to 99.7 %
Driver Drowsiness Detection Using Gray Wolf Optimizer Based on Face and Eye Tracking
It is critical today to provide safe and collision-free transport. As a result, identifying the driver’s drowsiness before their capacity to drive is jeopardized. An automated hybrid drowsiness classification method that incorporates the artificial neural network (ANN) and the gray wolf optimizer (GWO) is presented to discriminate human drowsiness and fatigue for this aim. The proposed method is evaluated in alert and sleep-deprived settings on the driver drowsiness detection of video dataset from the National Tsing Hua University Computer Vision Lab. The video was subjected to various video and image processing techniques to detect the drivers’ eye condition. Four features of the eye were extracted to determine the condition of drowsiness, the percentage of eyelid closure (PERCLOS), blink frequency, maximum closure duration of the eyes, and eye aspect ratio (ARE). These parameters were then integrated into an ANN and combined with the proposed method (gray wolf optimizer with ANN [GWOANN]) for drowsiness classification. The accuracy of these models was calculated, and the results demonstrate that the proposed method is the best. An Adadelta optimizer with 3 and 4 hidden layer networks of (13, 9, 7, and 5) and (200, 150, 100, 50, and 25) neurons was utilized. The GWOANN technique had 91.18% and 97.06% accuracy, whereas the ANN model had 82.35% and 86.76%
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