Mohd Hamiruce Marhaban

Infrared Heating in Food Drying: An Overview

This article aims to review and analyze the aspects and characteristics related to infrared food drying. Indeed, with a review of 100 relevant publications all dealing with infrared food drying, this article notes that infrared drying has several advantages over other common food drying methods. Shorter drying time, a better final dried product quality, and more energy savings in the process are revealed as the most important advantages of infrared drying over convective heat drying. Infrared dryers can also be easily combined with other drying methods such as hot air, microwave, vibration, and vacuum. This article clearly shows that using infrared heating for food drying purposes has become more popular in the last decade and its application in the industrial drying of different foodstuffs has been employed widely.

3D facial expression recognition using maximum relevance minimum redundancy geometrical features

In recent years, facial expression recognition (FER) has become an attractive research area, which besides the fundamental challenges, it poses, finds application in areas, such as human-computer interaction, clinical psychology, lie detection, pain assessment, and neurology. Generally the approaches to FER consist of three main steps: face detection, feature extraction and expression recognition. The recognition accuracy of FER hinges immensely on the relevance of the selected features in representing the target expressions. In this article, we present a person and gender independent 3D facial expression recognition method, using maximum relevance minimum redundancy geometrical features. The aim is to detect a compact set of features that sufficiently represents the most discriminative features between the target classes. Multi-class one-against-one SVM classifier was employed to recognize the seven facial expressions; neutral, happy, sad, angry, fear, disgust, and surprise. The average recognition accuracy of 92.2% was recorded. Furthermore, inter database homogeneity was investigated between two independent databases the BU-3DFE and UPM-3DFE the results showed a strong homogeneity between the two databases.

Digital-signal-processor-based waveform generator

This note describes a digital signal processor (DSP) based waveform generator, which can generate a sine wave, up to 24 kHz, a square wave, up to 5 kHz, and a triangular wave, up to 12 kHz. A DSP starter kit with Code Composer Studio has been used in the design of a waveform generator. The waveform generators can also produce periodic arbitrary waveforms and amplitude modulated signals. Two synchronized signals can be obtained by using the waveform generator too. The spectral components of the signals generated are found comparable with a commercially available signal generator. The total harmonic distortion of the sine wave generated is less than 0.6%.

Quasi‐ARX neural network based adaptive predictive control for nonlinear systems

In this paper, a new switching mechanism is proposed based on the state of dynamic tracking error so that more information will be provided –not only the error but also a one up to pth differential error will be available as the switching variable. The switching index is based on the Lyapunov stability theory. Thus the switching mechanism can work more effectively and efficiently. A simplified quasi-ARX neural-network (QARXNN) model presented by a state-dependent parameter estimation (SDPE) is used to derive the controller formulation to deal with its computational complexity. The switching works inside the model by utilizing the linear and nonlinear parts of an SDPE. First, a QARXNN is used as an estimator to estimate an SDPE. Second, by using SDPE, the state of dynamic tracking error is calculated to derive the switching index. Additionally, the switching formula can use an SDPE as the switching variable more easily. Finally, numerical simulations reveal that the proposed control gives satisfactory tracking and disturbance-rejection performances. Experimental results demonstrate its effectiveness.

Fundamental of an efficient and reliable staircase multilevel inverter for photovoltaic application

Due to high initial cost of photovoltaic generators, it is necessary to use high efficient converters to convert DC output of Photovoltaic systems to AC. This is done by efficient inverters. Between various inverter structures, staircase output inverters have a special place. Most of these inverters use structures that are constituted of series-connected switches. This limits efficiency and reliability. In this paper, an efficient and reliable staircase output inverter structure based on two ladders of switches is discussed. The major advantages of this structure are higher reliability and efficiency. This structure has low on-state power dissipation which means more performance especially when working with low voltage low power photovoltaic systems. The other advantage of this inverter is reliability when switches fail in form of open circuit. By choosing a special switching strategy, this inverter has ability to continue working with some failed open circuit switches. Increasing the number of levels increases the reliability of this inverter. Moreover, low switching frequency, let to use Photovoltaic output isolator as driver for switches, which means more capability for compactness in Integrated Power Modules (IPM). In this paper, first the structure of this inverter is discussed then the on-state power dissipation is calculated in form of using Mosfets and other p-n junction switches, then simulation result is brought.

Digital Signal Processing Based Waveform Generator for Flickermeter Calibration Test System

This paper describes a method of waveform generation using digital signal processing processor for flickermeter calibration test system. Flickermeter is a power analyzer designed to quantify to what degree the light intensity variation caused by voltage changes will irritate test subjects. Calibration test system for flickermeters is a system used to generate and measure accurately all the modulated test signals required for testing flickermeters [1]. Two waveform generators are needed in the system to produce the test conditions; one represents the mains frequency, generating frequency of 50 Hz while another represents the modulating frequency, generating frequencies from 2-25 Hz. The modulating frequencies, acting as flicker, are to be applied with the main frequency, resulting in modulation of frequencies. The DSP processor TMS320C6713DSK with code composer studio has been used to generate the two waveforms. It generates waveforms with different frequencies by using the look-up tables for the required waveforms up to 32 kHz. The required waveform, amplitude, and frequency can be programmed by the user. The DSP processor has also been programmed to produce amplitude modulated signal. Using the stereo audio codec of the kit, two difference types of frequencies have been generated simultaneously.

Analysis on the torque characteristics due to outer rotor displacement in the double rotor switched reluctance machine

The paper presents the influence on torque characteristics of the outer rotor displacement in the double rotor reluctance motor. At the first stage the magnetic equivalent circuit of the machine is developed based on the magnetic circuit of the machine in each of the parts that describes their own reluctances. From the equivalent circuit at the particular position the net reluctance is calculated. The magnetic circuit reluctances include due to the iron core of the stator, the rotor and that of the air gaps. The air gap reluctance in different rotor position influences predominantly the torque characteristics as the torque development highly dependent upon the flux linkages at any position. The changing of the pole arc essentially improves the extended flux linkage capability. Hence an investigation into the variations on the displacement of the rotor pole is imperative. In this investigation attempt is made only on the displacement of the outer rotor pole with respect to that of the inner rotor pole. From the results it is inferred that displacing the outer rotor by 3 degrees evolves an improvement in the torque characteristics.

Improved SIFT algorithm for place categorization

The main aim of this paper is an improvement of the famous Scale Invariant Feature Transform (SIFT) algorithm used in place categorization. Masking approach to reduce the computational complexity of SIFT have been proposed. Tradeoff between key points and processing time on feature extraction has been used. Selected parameters used in the experiment demonstrated that the computational cost of SIFT in feature extraction can be reduced to half. The categorization performance techniques of the masked image achieved good accuracy of more than 80% and further experimental results on classification using nearest neighbor achieved good results. The proposed method will help to minimize computation cost in SIFT thereby, improving the performance of robotic mapping, navigation, and matching.

Nonlinear Model-Predictive Control Based on Quasi-ARX Radial-Basis Function-Neural-Network

A nonlinear model-predictive control (NMPC) is demonstrated for nonlinear systems using an improved fuzzy switching law. The proposed moving average filter fuzzy switching law (MAFFSL) is composed of a quasi-ARX radial basis function neural network (RBFNN) prediction model and a fuzzy switching law. An adaptive controller is designed based on a NMPC. a MAFFSL is constructed based on the system switching criterion function which is better than the (ON/OFF) switching law and a RBFNN is used to replace the neural network (NN) in the quasi-ARX black box model which is understood in terms of parameters and is not an absolute black box model, in comparison with NN. The proposed controller performance is verified through numerical simulations to demonstrate the effectiveness of the proposed method.