Performance Analysis of 12Slot-14Pole for HEFSM and FEFSM with Outer-Rotor Configuration

Recently, research on flux switching machines (FSMs) become an attractive research topic due to several excessive advantages of robust rotor structure, high torque and power capability, and low manufacturing cost that suitable for heavy applications. Nevertheless, most of research have been reported are mainly focused on inner-rotor configuration. The outer-rotor configuration of electric machines are more applicable for direct drive application especially for in-wheel drive electric vehicles (EVs) due to higher torque at low speed and constant power at high operating region. Therefore, this paper presents performance analysis of 12Slot-14Pole hybrid excitation flux switching machine (HEFSM) and field excitation flux switching machine(FEFSM) with outer-rotor configuration. To confirm the machine’s operating principles, coil test analysis, magnetic flux characteristics, cogging torque, flux line and torque characteristics at various current densities for both machines are carried out using twodimensional finite element analysis (2D-FEA). The results obtained show that the HEFSM with outer-rotor configuration has higher torque and power compared with the outer-rotor FEFSM. Since, the machine’s performances are still far from the target torque and power, design optimization will be conducted to meet the target for direct drive EV application

Image fusion based multi resolution and frequency partition discrete cosine transform for palm vein recognition

The rapid growth of technology has increased the demand for automated security systems. Due to the accessibility of the palm region and the unique characteristics of each individual's palm vein features, such biometrics have been receiving particular attention. In the published research relating to palm vein biometrics, usually only a single image is used to supply the data for recognition purposes. Previous experimental work has demonstrated that the fusion of multiple images is able to provide richer feature information resulting in an improved classification performance. However, although most of the image fusion techniques are able to preserve the vein pattern, the fused image is often blurred, the colors are distorted and the spatial resolution reduced. In this paper, the multi-resolution discrete cosine transform (MRDCT) and frequency partition DCT (FPDCT) image fusion are applied and are able to extract the finer details of vein patterns while reducing the presence of noise in the image. The performance shows that the use of MRDCT and FPDCT was able to improve recognition rate compared to using a single image. The equal error rate improvement is also significant, falling to 9% in 700nm image, 7% in 850nm image and 6% in 940nm image

Activation energy for the oxidation of Malaysian coal chars

The oxidation of two Malaysian coal chars has been studied by means of a thermal gravimetric analyser (TGA). The weight-loss data were analysed by the Temperature Program Reaction (TPR) technique, which employed the random pore model of Bhatia & Perlmutter1. All experiments were conducted within a temperature range of 698-773 K (isothermal condition) and heating rates of 2-10 K min-1 (dynamic condition) with char samples in the size range 53-75 μm. It was found that the random pore model can accurately describe the oxidation of char to yield activation energy that is similar to that obtained from model free kinetics, provided the structural parameter ψ, which is an input to the model, is taken as an adjustable parameter

Compact Dual-Wavelength Laser Generation Using Highly Concentrated Erbium-Doped Fiber Loop Attached to Microfiber Coupler

A compact and low noise dual-wavelength fiber laser is demonstrated using a 70-cm-long Erbium-doped fiber loop attached to a microfiber coupler. The coupler functions to inject a 980-nm pump light as well as to tap out the output. At the maximum pump power of 8.4 mW, dual-wavelength laser is obtained at 1537.7 and 1551.4 nm with peak powers of 20.5 and 20.9 dBm, respectively. Both laser outputs are stable with a signal to noise ratio of more than 35 dB at room temperature. Both 1537.7 and 1551.4 nm lasers start to lase at threshold pump power as small as 2.5 mW with efficiencies of 0.14% and 0.10%, respectively

Erbium-doped fibre ring laser based on microfibre coupler

A compact erbium-doped fibre (EDF) laser is demonstrated which uses a microfibre coupler and a highly concentrated EDF loop. The coupler functions to inject the pump light and tap out the output. The EDF laser operates at 1526.3 nm, with a signal-to-noise ratio of about 26 dB. The maximum output power 20 µW is obtained at the pump power 18.6mW. We have obtained the slope efficiencies of the laser 0.12, 0.06, 0.04 and 0.02% at the EDF lengths fixed at 90, 78, 66 and 51 cm, respectively. The lowest lasing-pump power threshold is achieved at 3.8 mW

Simulation, optimization and parametric studies of a solid catalyzed gas phase ethylene polymerization fluidized bed reactor

A steady-state model incorporating interactions between separate bubbles and emulsion phases in a fluidized-bed polyethylene reactor is employed to study the effect of operating conditions on the stability of gas-phase polyethylene reactors. A simple optimization program is developed to find the optimum combination of operating parameters at which the maximum polyethylene production rate is achieved with the constraints only on the reactor temperature, which should not exceed the melting point of polymer. Using the optimum values found, the parametric investigation for the effect of the catalyst deactivation rate constant and process operating parameters, such as the catalyst feed rate and the gas superficial to minimum fluidization velocity on system behavior are investigated. The investigations reveal that, the fluidized bed polyethylene reactor is prone to show unstable behavior and temperature oscillations, and the optimum polyethylene production rate could be achieved when it operates close to its melting point under a suitable controller to avoid polymer melting. Copyright © 2

Equilibrium of CO2 in aqueous diethanolamine (DEA) and Amino Methyl Propanol (AMP) solutions

Equilibrium data of CO2 in aqueous solutions of DEA and AMP for a range of CO2 partial pressure (0.5-100 kPa) and temperature (25-80°C) obtained using a stirred cell reactor is presented in this paper. The data were analyzed using the Deshmukh and Mather Model. It has been found that this model is able to predict results which are close to the experimental data in terms of the total CO2 loadings and the pH of the solution, an additional parameter which was monitored in this work. Comparison was also made with other published results using the different interaction parameters generated in this work. Good agreement between predicted and experimental values were also observed

Demonstration of acoustic vibration sensor based on microfiber knot resonator

A compact microfiber-based acoustic vibration sensor is demonstrated using microfiber knot resonator (MKR) structure, which is fabricated by flame brushing technique. It is observed that the extinction ratio of the resonant spectrum of the knot resonator is linearly proportional to the vibration amplitude. This is attributed to the interruption of the effective coupling of the MKR which is correlated with the exposed vibration force. It is also shown that the resonant wavelength shifts by about 0.19 nm as the normalized vibration energy is increased from 0 to 10%. The performance of the sensor is then further investigated by monitoring the fast Fourier transform (FFT) of the signal when the MKR is exposed to various vibration frequencies as a narrowband 1545 nm laser is injected into the MKR. In the spectra of the signals, the frequency of the applied vibration is clearly shown as it has the highest magnitude followed by the accompanying harmonics. This holds true for all vibration frequencies