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29,939 Article Results

Detailed analysis of grid connected and islanded operation modes based on P/U and Q/f droop characteristics

10.11591/ijpeds.v12.i2.pp772-782
Qusay Salem , Khaled Alzaaree
This paper presents a thorough control structure of the distributed generators inside the microgrid during both grid-connected and islanded operation modes. These control structures of the DGs voltage source inverters are implemented in synchronous reference frame (SRF) and controlled using linear PI controllers. By implementing the control structures, the desired real and reactive power can be efficiently transferred to the local loads and the utility load by the microgrid generating units. A modified droop control technique is introduced to facilitate the microgrid performance during both modes of operation. The active and reactive power sharing of the load demand between the utility grid and the microgrid can be performed by this drop control technique during the islanded mode. The system performance during intentional islanding event and utility load increase is investigated. The effectiveness of the offered control structures is confirmed through simulation results during both modes of operation.
Volume: 12
Issue: 2
Page: 772-782
Publish at: 2021-06-01

Hybrid memristor-CMOS implementation of logic gates design using LTSpice

10.11591/ijece.v11i3.pp2003-2010
Wan Mohd Hashimi Wan Mohamad Sharif , Mohd Faizul Md Idros , Syed Abdul Mutalib Al-Junid , Fairul Nazmi Osman , Abdul Hadi Abdul Razak , Abdul Karimi Halim , Muhammad Adib Harun
In this paper, a hybrid memristor-CMOS implementation of logic gates simulated using LTSpice. Memristors' implementation in computer architecture designs explored in various design structures proposed by researchers from all around the world. However, all prior designs have some drawbacks in terms of applicability, scalability, and performance. In this research, logic gates design based on the hybrid memristor-CMOS structure presented. 2-inputs AND, OR, NAND, NOR, XOR, and XNOR are demonstrated with minimum components requirements. In addition, a 1-bit full adder circuit with high performance and low area consumption is also proposed. The proposed full adder only consists of 4 memristors and 7 CMOS transistors. Half design of the adder base on the memristor component created. Through analysis and simulations, the memristor implementation on designing logic gates using memristor-CMOS structure demonstrated using the generalized metastable switch memristor (MSS) model and LTSpice. In conclusion, the proposed approach improves speed and require less area.
Volume: 11
Issue: 3
Page: 2003-2010
Publish at: 2021-06-01

The origin of cycle life degradation of a lead-acid battery under constant voltage charging

10.11591/ijpeds.v12.i2.pp986-993
Arif Hariyadi , Awan Nugroho , Suwarno Suwarno
Due to its low cost and recycle-ability, the lead-acid battery is widely used in mobile and stationary applications. Despite much research on lead-acid batteries, the effect of charging voltage on the degradation mechanism requires further investigation. In particular, the origin of cycle life degradation remains unclear. In the present work, by using electrochemical tests and materials characterization, we studied the effect of charging voltage at voltages slightly higher than the open-circuit potential (OCP) i.e., 103-107% OCP, on the battery life cycle. The highest degradation was observed at 105% OCP charging voltage. Based on the materials characterization results, we found that the degradation of a lead-acid battery is influenced by the amount of hard sulfate and the sulfate particles' size.
Volume: 12
Issue: 2
Page: 986-993
Publish at: 2021-06-01

Contrast-distorted image quality assessment based on curvelet domain features

10.11591/ijece.v11i3.pp2595-2603
Ismail Taha Ahmed , Chen Soong Der , Baraa Tareq Hammad , Norziana Jamil
Contrast is one of the most popular forms of distortion. Recently, the existing image quality assessment algorithms (IQAs) works focusing on distorted images by compression, noise and blurring. Reduced-reference image quality metric for contrast-changed images (RIQMC) and no reference-image quality assessment (NR-IQA) for contrast-distorted images (NR-IQA-CDI) have been created for CDI. NR-IQA-CDI showed poor performance in two out of three image databases, where the pearson correlation coefficient (PLCC) were only 0.5739 and 0.7623 in TID2013 and CSIQ database, respectively. Spatial domain features are the basis of NR-IQA-CDI architecture. Therefore, in this paper, the spatial domain features are complementary with curvelet domain features, in order to take advantage of the potent properties of the curvelet in extracting information from images such as multiscale and multidirectional. The experimental outcome rely on K-fold cross validation (K ranged 2-10) and statistical test showed that the performance of NR-IQA-CDI rely on curvelet domain features (NR-IQA-CDI-CvT) significantly surpasses those which are rely on five spatial domain features.
Volume: 11
Issue: 3
Page: 2595-2603
Publish at: 2021-06-01

Novel hybrid framework for image compression for supportive hardware design of boosting compression

10.11591/ijece.v11i3.pp1985-1993
Premachand D. R. , U. Eranna
Performing the image compression over the resource constrained hardware is quite a challenging task. Although, there has been various approaches being carried out towards image compression considering the hardware aspect of it, but still there are problems associated with the memory acceleration associated with the entire operation that downgrade the performance of the hardware device. Therefore, the proposed approach presents a cost effective image compression mechanism which offers lossless compression using a unique combination of the non-linear filtering, segmentation, contour detection, followed by the optimization. The compression mechanism adapts analytical approach for significant image compression. The execution of the compression mechanism yields faster response time, reduced mean square error, improved signal quality and significant compression ratio performance.
Volume: 11
Issue: 3
Page: 1985-1993
Publish at: 2021-06-01

Data bank: nine numerical methods for determining the parameters of weibull for wind energy generation tested by five statistical tools

10.11591/ijpeds.v12.i2.pp1114-1130
Ahmed Samir Badawi , Siti Hajar Yusoff , Alhareth Mohammed Zyoud , Sheroz Khan , Aisha Hashim , Yılmaz Uyaroğlu , Mahmoud Ismail
This study aims to determine the potential of wind energy in the mediterranean coastal plain of Palestine. The parameters of the Weibull distribution were calculated on basis of wind speed data. Accordingly, two approaches were employed: analysis of a set of actual time series data and theoretical Weibull probability function. In this analysis, the parameters Weibull shape factor ‘k’ and the Weibull scale factor ‘c’ were adopted. These suitability values were calculated using the following popular methods: method of moments (MM), standard deviation method (STDM), empirical method (EM), maximum likelihood method (MLM), modified maximum likelihood method (MMLM), second modified maximum likelihood method (SMMLM), graphical method (GM), least mean square method (LSM) and energy pattern factor method (EPF). The performance of these numerical methods was tested by root mean square error (RMSE), index of agreement (IA), Chi-square test (X2), mean absolute percentage error (MAPE) and relative root mean square error (RRMSE) to estimate the percentage of error. Among the prediction techniques. The EPF exhibited the greatest accuracy performance followed by MM and MLM, whereas the SMMLM exhibited the worst performance. The RMSE achieved the best prediction accuracy, whereas the RRMSE attained the worst prediction accuracy.
Volume: 12
Issue: 2
Page: 1114-1130
Publish at: 2021-06-01

Modeling and control of two five-phase induction machines connected in series powered by matrix converter

10.11591/ijpeds.v12.i2.pp685-694
Mohamed Nekkaz , Abdelkader Djahbar , Rachid Taleb
The two five-phase Induction Motor (IM) drive system that is serially connected is available in literature. The power supply of such system is considered as a matrix converter (a direct AC to AC converter system) by three and five-phases outputs. The main benefit from the drive topology is the sinusoidal source as a side current with a controllable input side power factor. The decoupled control is achieved similarly to the inverter based drive system. In this paper; the decoupled control of two five-phase induction machines serially connected and powered by a five-phase matrix converter as well as analytical and simulation results are presented.
Volume: 12
Issue: 2
Page: 685-694
Publish at: 2021-06-01

High clarity speech separation using synchro extracting transform

10.11591/ijece.v11i3.pp2621-2630
Shahin M. Abdulla , J. Jayakumari
Degenerate unmixing estimation technique (DUET) is the most ideal blind source separation (BSS) method for underdetermined conditions with number of sources exceeds number of mixtures. Estimation of mixing parameters which is the most critical step in the DUET algorithm, is developed based on the characteristic feature of sparseness of speech signals in time frequency (TF) domain. Hence, DUET relies on the clarity of time frequency representation (TFR) and even the slightest interference in the TF plane will be detrimental to the unmixing performance. In conventional DUET algorithm, short time Fourier transform (STFT) is utilized for extracting the TFR of speech signals. However, STFT can provide on limited sharpness to the TFR due to its inherent conceptual limitations, which worsens under noise contamination. This paper presents the application of post-processing techniques like synchro squeezed transform (SST) and synchro extracting transform (SET) to the DUET algorithm, to improve the TF resolution. The performance enhancement is evaluated both qualitatively and quantitatively by visual inspection, Renyi entropy of TFR and objective measures of speech signals. The results show enhancement in TF resolution and high clarity signal reconstruction. The method also provides adequate robustness to noise contamination.
Volume: 11
Issue: 3
Page: 2621-2630
Publish at: 2021-06-01

Grid-connected control of PV-Wind hybrid energy system

10.11591/ijpeds.v12.i2.pp1228-1238
Hakim Azoug , Hocine Belmili , Fekkak Bouazza
ABSTRACT Article history: Received Oct 14, 2020 Revised Mar 22, 2021 Accepted Apr 23, 2021 This paper presented a strategy for modeling, simulation and control of a hybrid grid connected power system which is in fact a rather complex system. In this work, we study how to use two renewable energies in an efficient manner without any disturbing of the main network. Our hybrid energy system (HES) is composed by two renewable energy sources, the photovoltaic source and wind source. It is better for these two systems to work at their maximum power in order to return the investment cost of the system. The proposed solution is to connect those generators to the electrical grid via the AC bus with trackers. Where the photovoltaic generator (PVG) is followed by a DC/DC boost converter, controlled by a perturb and observe (P&O) tracker, then followed by a three-phase voltage inverter (3-ph-VSI) which is controlled by the watt-var decoupled method. The wind system is based on permanent magnet synchronous machine (PMSM) which is used as a variable speed generator and directly connected to the turbine (without gearbox) followed by back-to-back converters. The grid side converter (GSC) allows us to control the DC bus voltage and unity power factor, while the machine side converter (MSC) ensures us to control the PMSM speed. Knowing that pitch angle control is not considered in our study. The MPPT control strategy, which is based on the optimum peak speed ratio (OTSR), is used to ensure the most energy efficiency despite variations in wind speed. The coupling of the two systems is done via the Point of Common Collecting (PCC). Finally, simulation results show the feasibility of our solution and the good performances of the proposed control strategy, applied for mediumsized HES in power generation. They also demonstrate that such system topology is very advantageous.
Volume: 12
Issue: 2
Page: 1228-1238
Publish at: 2021-06-01

Investigating the PageRank and sequence prediction based approaches for next page prediction

10.11591/ijece.v11i3.pp2229-2237
Nguyen Thon Da , Tan Hanh
Discovering unseen patterns from web clickstream is an upcoming research area. One of the meaningful approaches for making predictions is using sequence prediction that is typically the improved compact prediction tree (CPT+). However, to increase this method's effectiveness, combining it with at least other methods is necessary. This work investigates such PageRank-based methods related to sequence prediction as All-K-Markov, DG, Markov 1st, CPT, CPT+. The experimental results proved that the integration of CPT+ and PageRank is the right solution for next page prediction in terms of accuracy, which is more than a standard method of approximately 0.0621%. Still, the size of the newly created sequence database is reduced up to 35%. Furthermore, our proposed solution has an accuracy that is much higher than other ones. It is intriguing for the next phase (testing one) to make the next page prediction in terms of time performance.
Volume: 11
Issue: 3
Page: 2229-2237
Publish at: 2021-06-01

Bigradient neural network-based quantum particle swarm optimization for blind source separation

10.11591/ijai.v10.i2.pp355-364
Hussein M. Salman , Ali Kadhum M. Al-Qurabat , Abd Alnasir Riyadh Finjan
An independent component analysis (ICA) is one of the solutions of a blind source separation problem. ICA is a statistical approach that depends on the statistical properties of the mixed signals. The purpose of the ICA method is to demix the mixed source signals (observation signals) and rcovering those signals. The abbreviation of the problem is that the ICA needs for optimizing by using one of the optimization approaches as swarm intelligent, neural neworks, and genetic algorithms. This paper presents a hybrid method to optimize the ICA method by using the quantum particle swarm optimization method (QPSO) to optimize the Bigradient neural network method that applies to separate mixed signals and recover sources signals. The results of an implement this work prove that this method gave good results comparing with other methods such as the Bigradient neural network and the QPSO method, based on several evaluation measures as signal-to-noise ratio, signal-to-distortion ratio, absolute value correlation coefficient, and the computation time.
Volume: 10
Issue: 2
Page: 355-364
Publish at: 2021-06-01

Design and control of grid-connected solar-wind integrated conversion system with DFIG supplying three-phase four-wire loads

10.11591/ijpeds.v12.i2.pp1150-1161
Arjun Kumar GB , Shivashankar Shivashankar , Keshavamurthy Keshavamurthy
This paper describes the architecture and control of an autonomous hybrid solar-wind system (AHSWS) powered distributed generation system supplying to a 3ϕ-4 wire system. It includes a nonlinear controlling technique for maximum power point tracking (MPPT) used in doubly fed induction generator dependent wind energy translation scheme and solar photovoltaic system (SPVS). In the hybrid model, the DC/DC converter output from the PV system is explicitly coupled with the DC-link of DFIG's back-to-back converter. An arithmetical model of the device is developed, derived using a suitable d-q reference frame. The grid-voltage-oriented vector regulation is required to manage the GSC to keep the steady-state voltage of the DC bus and to adjust reactive power on the grid side. Also, the stator-voltageoriented control scheme offers a stable function of DFIG to regulate the RSC on the stator edge for reactive and active power management in this approach. DC/DC converter is being used to maintain the maximum power from SPVS. A Perturb & Observe method is used for tracing maximum power in an SPVS. The simulation designs of 4.0kW DFIG and 4.5kW solar array simulator are built-in SIMPOWER software kit of MATLAB, it is shown to achieve optimum efficiency under various mechanical and electrical circumstances. It can produce rated frequency and voltage in both scenarios.
Volume: 12
Issue: 2
Page: 1150-1161
Publish at: 2021-06-01

K-means clustering-based WSN protocol for energy efficiency improvement

10.11591/ijece.v11i3.pp2371-2377
Jong-Yong Lee , Daesung Lee
Since it is very difficult to replace or recharge the batteries of the sensor nodes in the wireless sensor network (WSN), efficient use of the batteries of the sensor nodes is a very important issue. This has a deep relationship with the lifetime of the network. If the node's energy is exhausted, the node is no longer available. If a certain number of nodes (50% or 80%) in a network consumes energy completely, the whole network will not work. Therefore, various protocols have been proposed to maintain the network for a long time by minimizing energy consumption. In recent years, a protocol using a K-means clustering algorithm, one of machine learning techniques, has been proposed. A KCED protocol is proposed in consideration of residual energy of a node, a cluster center, and a distance to a base station in order to improve a problem of a protocol using K-average gung zipper algorithm such as cluster center consideration.
Volume: 11
Issue: 3
Page: 2371-2377
Publish at: 2021-06-01

Controller design for PV experimental bench with ADRC strategy supervised by Labview created interface

10.11591/ijpeds.v12.i2.pp1162-1176
Naoufel Khaldi , Youssef Barradi , Khalida Zazi , Malika Zazi
The converter control scheme plays an important role in the performance of maximum power point tracking (MPPT) algorithms. In this work, a model has been analysed, designed and simulatedon Power Simulator software and in Matlab Simulink.A hardware implementation using a microcontroller (Arduino Mega 2560 based on ATmega2560) is provided, that operateson feedback from a PV panel voltage and current to control the operation of DCDC converter in order to draw maximum power. Newactive disturbance rejection control (ADRC) algorithm is required to extract the maximum power of the solar energy. This MPPT controller incorporates a boost topology that ensuresa two continuous battery in series (12V, 5Ah) charging in various conditions. The whole of the results shows in one hand that the converter efficiency is very satisfactory, and in the other hand a very good agreement between the results simulated and those experimental in terms of performance. The proposed system is designed in Proteus, and implemented on hardware with a graphical user interface built throughout Labview software.
Volume: 12
Issue: 2
Page: 1162-1176
Publish at: 2021-06-01

The health beliefs of patient with type 2 diabetes mellitus who use herbs as a complement to self-care

10.11591/ijphs.v10i2.20729
Anita Joeliantina , Hepta Nur Anugrahini , Jujuk Proboningsih
Diabetes mellitus type 2 patients who have a tendency to use herbs, are based on the patient's health belief that herbal medicine is a natural ingredient that has efficacy and is safe. This study aimed to explore health beliefs as predictors of herbal use as a complement to diabetes self-care. A cross-sectional study was conducted on 230 patients with type 2 diabetes mellitus who had been clinically diagnosed, received medical treatment and used herbs. The data was collected using a questionnaire at seven community health centers (Puskesmas) in Surabaya City. Data analysis using Partial Least Square. The indicator of health belief variables has a loading factor value>0.5: perceived vulnerability and severity (0.820), perceived benefits (0.739), perceived barriers (0.822), sense of self-efficacy (0.695). Health beliefs have a significant effect on the use of herbs as a complement to diabetes self-care, the value of T>1.97 (T>10.07). Health beliefs consisting of perceived vulnerability and severity, perceived benefits, perceived inhibition, and perceived self-efficacy were strong predictors associated with the use of herbs as a complement to diabetes self-care. Nurses as part of health workers must pay attention to patient health beliefs in providing education to patients.
Volume: 10
Issue: 2
Page: 265-271
Publish at: 2021-06-01
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