Articles

Access the latest knowledge in applied science, electrical engineering, computer science and information technology, education, and health.

Filter Icon

Filters article

Years

FAQ Arrow
0
0

Source Title

FAQ Arrow

Authors

FAQ Arrow

29,939 Article Results

Image mixed gaussian and impulse noise elimination based on sparse representation model

10.11591/ijeecs.v23.i3.pp1440-1450
Ahmed Abdulqader Hussein , Sabahaldin A. Hussain , Ahmed Hameed Reja
A modified mixed Gaussian plus impulse image denoising algorithm based on weighted encoding with image sparsity and nonlocal self-similarity priors regularization is proposed in this paper. The encoding weights and the priors imposed on the images are incorporated into a variational framework to treat more complex mixed noise distribution. Such noise is characterized by heavy tails caused by impulse noise which needs to be eliminated through proper weighting of encoding residual. The outliers caused by the impulse noise has a significant effect on the encoding weights. Hence a more accurate residual encoding error initialization plays the important role in overall denoising performance, especially at high impulse noise rates. In this paper, outliers free initialization image, and an easier to implement a parameter-free procedure for updating encoding weights have been proposed. Experimental results demonstrate the capability of the proposed strategy to recover images highly corrupted by mixed Gaussian plus impulse noise as compared with the state of art denoising algorithm. The achieved results motivate us to implement the proposed algorithm in practice.
Volume: 23
Issue: 3
Page: 1440-1450
Publish at: 2021-09-01

Active cooling photovoltaic with IoT facility

10.11591/ijpeds.v12.i3.pp1494-1504
Muhammad Nizam Kamarudin , Sahazati Md. Rozali , Mohd Saifuzam Jamri
Harvesting energy from the sun makes the photovoltaic (PV) power generation a promising technology. To obtain a consistent state of charge (SOC), consistent energy must be harvested and efficiently directed to the battery. Overcharging or undercharging phenomena decreases the lifetime of the battery. Besides, the effect of irradiance toward solar in term of sunlight intensity effects the efficiency and hence, sluggish the SOC. The main problem of the solar panel revealed when the temperature has increased, the efficiency of solar panel will also be decreased. This manuscript reports the finding of developing an automatic active cooling system for a solar panel with a real time energy monitoring system with internet-of-things (IoT) facility. The IoT technology assists user to measure the efficiency of the solar panel and SOC of the battery in real time from any locations. The automatic active cooling system is designed to improve the efficiency of the solar panel. The effectiveness of the proposed system is proven via the analysis of the effect of active cooling toward efficiency and SOC of photovoltaic system. The results also tabulate the comparative studies of active-to-passive cooling system, as well as the effect of cooling towards SOC and efficiency of the solar panel.
Volume: 12
Issue: 3
Page: 1494-1504
Publish at: 2021-09-01

Examining child obesity risk level using fuzzy inference system

10.11591/ijphs.v10i3.20928
Febrina Sari , Desyanti Desyanti , Teuku Radillah , Siti Nurjannah , Julimar Julimar , Juwita Yanti Pakpahan
The doctor will determine the risk level of childhood obesity by using standard calculations, namely measuring the child's weight and height, and many other factors. Then the doctor will calculate the child's body mass index (BMI). The results of calculations made by the doctor will be compared with standard/normal values set by FAO/WHO, to obtain the level of risk of obesity in children. This study aims to analyze the risk level of obesity in children using the Sugeno method of Fuzzy Inference system, using the trapezoidal membership function and involving six input variables such as exercise habits, consumption of fast food, history of obesity of parents, and others. The application of the fuzzy inference system Sugeno method can help doctors to analyze the risk level of childhood obesity quickly and accurately with an accuracy rate of 85%. The results of the implementation of the Sugeno method of Fuzzy Inference system showed that out of 140 children who were the object of the study, 119 children received a diagnosis of the level of risk of obesity which was the same as the diagnosis made by a doctor.
Volume: 10
Issue: 3
Page: 679-687
Publish at: 2021-09-01

Implementation on the dSPACE 1104 of VOC-SVM based anti-windup PI Controller of a three-phase PWM rectifier

10.11591/ijpeds.v12.i3.pp1586-1597
J. lamterkati , L. Ouboubker , M. Khafallah , A. El afia
The study made in this paper concerns the use of the voltage-oriented control (VOC) of three-phase pulse width modulation (PWM) rectifier with constant switching frequency. This control method, called voltage-oriented controlwith space vector modulation (VOC-SVM). The proposed control scheme has been founded on the transformation between stationary (α-β) and and synchronously rotating (d-q) coordinate system, it is based on two cascaded control loops so that a fast inner loop controls the grid current and an external loop DC-link voltage, while the DC-bus voltage is maintained at the desired level and ansured the unity power factor operation. So, the stable state performance and robustness against the load’s disturbance of PWM rectifiers are boths improved. The proposed scheme has been implemented and simulated in MATLAB/Simulink environment. The control system of the VOC-SVM strategy has been built based on dSPACE system with DS1104 controller board. The results obtained show the validity of the model and its control method. Compared with the conventional SPWM method, the VOC-SVM ensures high performance and fast transient response.
Volume: 12
Issue: 3
Page: 1586-1597
Publish at: 2021-09-01

Adaptive backstepping controller design based on neural network for PMSM speed control

10.11591/ijpeds.v12.i3.pp1940-1952
E. Sabouni , B. Merah , I. K. Bousserhane
The aim of this research is the speed tracking of the permanent magnet synchronous motor (PMSM) using an intelligent Neural-Network based adapative backstepping control. First, the model of PMSM in the Park synchronous frame is derived. Then, the PMSM speed regulation is investigated using the classical method utilizing the field oriented control theory. Thereafter, a robust nonlinear controller employing an adaptive backstepping strategy is investigated in order to achieve a good performance tracking objective under motor parameters changing and external load torque application. In the final step, a neural network estimator is integrated with the adaptive controller to estimate the motor parameters values and the load disturbance value for enhancing the effectiveness of the adaptive backstepping controller. The robsutness of the presented control algorithm is demonstrated using simulation tests. The obtained results clearly demonstrate that the presented NN-adaptive control algorithm can provide good trackingperformances for the speed trackingin the presence of motor parameter variation and load application.
Volume: 12
Issue: 3
Page: 1940-1952
Publish at: 2021-09-01

EFL university teachers’ perspectives in written corrective feedback and their actual applications

10.11591/ijere.v10i3.21641
Windy Wahju Purnomo , Yazid Basthomi , Johannes Ananto Prayogo
This study aimed to investigate the English as a foreign language (EFL) university teachers’ perspective and their actual applications in providing written corrective feedback to the writing errors made by the EFL university students and their correlation. The study was based on 80 responses of a Google-Form survey distributed to EFL university teachers with various teaching experiences from the most parts of Indonesia. Correlational design was used in this research. Descriptive statistics and Pearson’s correlation tests were used to analyze data. The results indicated that the majority of teachers had perspectives that it is valuable to provide and vary the strategies of written corrective feedback. In addition, the teachers mostly applied both direct and indirect feedback in various strategies and they only sometimes provided corrections in all aspects of errors and reformulation. It was also found out that the Indonesian EFL university teachers’ perspectives in the written corrective on students’ writing errors highly correlated with their actual applications. The results of the study provide both theoretical and pedagogical implications. Theoretically, it enriches the body knowledge of feedback and EFL writing. Pedagogically, EFL teachers are also suggested to improve their knowledge on various feedback techniques and apply it in their classroom teaching and learning process. 
Volume: 10
Issue: 3
Page: 1089-1099
Publish at: 2021-09-01

A novel hybrid approach based artificial bee colony and salp swarm algorithms for solving ORPD problem

10.11591/ijeecs.v23.i3.pp1825-1837
Souheil Salhi , Djemai Naimi , Ahmed Salhi , Saleh Abujarad , Abdelouahab Necira
Optimal reactive power dispatch (ORPD) is an important task for achieving more economical, secure and stable state of the electrical power system. It is expressed as a complex optimization problem where many meta-heuristic techniques have been proposed to overcome various complexities in solving ORPD problem. A meta-heuristic search mechanism is characterized by exploration and exploitation of the search space. The balance between these two characteristics is a challenging problem to attain the best solution quality. The artificial bee colony (ABC) algorithm as a reputed meta-heuristic has proved its goodness at exploration and weakness at exploitation where the enhancement of the basic ABC version becomes necessary. Salp swarm algorithm (SSA) is a newly developed swarm-based meta-heuristic, which has the best local search capability by using the best global solution in each iteration to discover promising solutions. In this paper, a novel hybrid approach-based ABC and SSA algorithms (ABC-SSA) is that developed to enhance the exploitation capability of the ABC algorithm using SSA and applied for solving ORPD problem. The efficiency of ABC-SSA is investigated using two standard test systems IEEE-30 and IEEE-300 buses, and that by considering the famous objective functions in ORPD problem.
Volume: 23
Issue: 3
Page: 1825-1837
Publish at: 2021-09-01

Comparison of roughness index for Kitka and Koznica wind farms

10.11591/ijpeds.v12.i3.pp1872-1879
Bukurije Hoxha , Bedri Dragusha
Kosovo has limited renewable energy resources and its power generation sector is based on fossil fuels. Such a situation emphasizes the importance of active research and efficient use of renewable energy potential. According to the analysis of meteorological data for Kosovo, it can be concluded that among the most attractive potential wind power sites are the locations known as Kitka (42° 29' 41" N and 21° 36' 45" E) and Koznica (42° 39′ 32″ N, 21° 22′30″E). The two terrains in which the analysis was carried out are mountain areas, with altitudes of 1142 m (Kitka) and 1230 m (Koznica). the same measuring height, about 84 m above the ground, is obtained for these average wind speeds: Kitka 6,667 m/s and Koznica 6,16 m/s. Since the difference in wind speed is quite large versus a difference in altitude that is not being very large, analyses are made regarding the terrain characteristics including the terrain relief features. In this paper it will be studied how much the roughness of the terrain influences the output energy. Also, that the assumption to be taken the same as to how much they will affect the annual energy produced.
Volume: 12
Issue: 3
Page: 1872-1879
Publish at: 2021-09-01

From competition to collaboration: Unraveling teachers’ lesson study experiences

10.11591/ijere.v10i3.21101
Romiro G. Bautista , Wilfredo B. Baniqued
Lesson study is a professional development program among teachers. It reciprocates teachers’ development to students’ outcomes. It is also an act of leveraging classroom practices, enriching teachers’ content knowledge, and process skills and beliefs. This study explored the experiences of a group of science secondary school teachers that implemented the lesson study in their classes. Qualitative data were gathered from the informants’ interview during the implementation of the lesson study. Data were processed through document trail among the informants to ascertain the veracity of the transcribed responses, reflections, and observations. Thematic analysis revealed five themes on the experiences of the teachers in implementing the Lesson Study: developing a culture of oneness, crafting teachers’ competence through synergism, boosting teachers’ morale and confidence, refining the quality of the research lesson, and scheming avenues for critical thinking. It is, therefore, suggested that lesson study be implemented by all teachers across all subject-areas in the division and introduced among pre-service teachers to further discover its efficacy towards teachers’ development and students’ outcomes. Furthermore, it is strongly suggested that knowledgeable others be involved in the implementation of the lesson study as their presence were found significant in ensuring its success as most of the teachers are not specialized in the field that they are teaching.
Volume: 10
Issue: 3
Page: 921-929
Publish at: 2021-09-01

A comparative study for the performance operation of electric machine based on conventional and D-Q theories

10.11591/ijpeds.v12.i3.pp1304-1314
Sanabel M. AL hajzber , Ahmed J. Ali , Alya H. AL-Rifaie , Abdullah K. Shanshal
Induction motors are used widely in industrial applications, thanks to their high efficiency and reliability which nominates it as a good machine used in various application. Based on the application and accuracy, modeling processes of electric machines are carried out using different mathematical methods. The most common method for modeling electrical machines is based on solution of differential equations of voltages as well as calculating the time varying self-inductances and the mutual inductances based on the rotor angle. One of the most important features of this method is that the inductance is no long depend on the time varying voltage, which is the major problem facing the conventional model. But the D-Q modeling approach has several problems, the greatest of which is that the voltage applied on stator must be balanced in addition to the fact that the winding are sinusoidal distributed form. Herein this research is focused on build two models of a 3-Φ induction motor (IM) based on the two analytical approaches and compare them to clarify the difference. The results have been shown that the conventional model gives more accurate response when it is applied in both normal and upnormal operation. MATLAB/Simulink softare is used to construct the D-Q and classical abc IM models.
Volume: 12
Issue: 3
Page: 1304-1314
Publish at: 2021-09-01

Newly fault-tolerant indirect vector control for traction inverter

10.11591/ijpeds.v12.i3.pp1576-1585
Sara Zerdani , Mohamed Larbi Elhafyani , Hicham Fadil , Smail Zouggar
The traction inverter is a crucial power device in the electric vehicle’s powertrain, and its failure is intolerable as it would considerably compromise the system’s safety. For more reliable driving, installing a traction inverter that is sufficiently resistant to electrical failure is inherent. Due to its compact size and the small number of switches incorporated in three-phase four-switch inverter, this modular topology was used to compensate for the open switch’s failure. However, it is known to have manifold weaknesses mainly distinguished in the low-frequency region. This paper introduces a new fault-tolerant indirect control that handles the IGBT’s failure constituting the traction inverter. The fault compensator is designed first based on the Proportional Integral regulator combined with the notch filter to mitigate the current imbalance and restore the DC voltage equilibrium.Furthermore, to conceive a comprehensive fault-tolerant control, there must therefore contain an accurate fault detector. In this regard, an uncomplicated fault diagnosis method based on the current spectral analysis has been performed. The effectiveness of the submitted controller was validated by simulation using Matlab.
Volume: 12
Issue: 3
Page: 1576-1585
Publish at: 2021-09-01

Using Y-source network as a connector between turbine and network in the structure of variable speed wind turbine

10.11591/ijpeds.v12.i3.pp1644-1658
Mahmoud Zadehbagheri , Tole Sutikno , Rahim Ildarabadi
Environmental factors such as air pollution and increase in global warming by using polluting fuels are the most important reasons of using renewable and clean energy that runs in global community. Wind energy is one of the most suitable and widely used kind of renewable energy which had been in consideration so well. This paper introduces an electric power generationsystem of wind based on Y-source and improved Y-source inverter to deliver optimal electrical power to the network. This new converter is from impedance source converters family. This presented converter has more degrees of freedom to adjust voltage gain and modulation. Also, by limiting the range of simultaneous control (shooting through) while it maintains thehighest power of maximizer, it can operate in higher modulation range. This causes the reduce of stress in switching and thus it will improve the quality of output. Recommended system had been simulated in MATLAB/Simulink and shown results indicate accurate functionality.
Volume: 12
Issue: 3
Page: 1644-1658
Publish at: 2021-09-01

Soft computing and IoT based solar tracker

10.11591/ijpeds.v12.i3.pp1880-1889
Kanhaiya Kumar , Lokesh Varshney , A. Ambikapathy , Vrinda Mittal , Sachin Prakash , Prashant Chandra , Namya Khan
The significance of the solar energy is to intensify the effectiveness of the Solar Panel with the use of a primordial solar tracking system. Here we propounded a solar positioning system with the use of the global positioning system (GPS) , artificial neural network (ANN) and image processing (IP) . The azimuth angle of the sun is evaluated using GPS which provide latitude, date, longitude and time. The image processing used to find sun image through which centroid of sun is calculated and finally by comparing the centroid of sun with GPS quadrate to achieve optimum tracking point. Weather conditions and situation observed through AI decision making with the help of IP algorithms. The presented advance adaptation is analyzed and established via experimental effects which might be made available on the memory of the cloud carrier for systematization. The proposed system improve power gain by 59.21% and 10.32% compare to stable system (SS) and two-axis solar following system (TASF) respectively. The reduced tracking error of IoT based Two-axis solar following system (IoT-TASF) reduces their azimuth angle error by 0.20 degree.
Volume: 12
Issue: 3
Page: 1880-1889
Publish at: 2021-09-01

Determinants of medical students' empathy during clinical rotation

10.11591/ijphs.v10i3.20747
Resiana Citra , Rizma Adlia Syakurah , Eddy Roflin
Medical students in clinical rotation level have been developed comprehension and implementation of empathy, considering that they have already dealt with patients in the first hand, whereas professionalism and ethics are two main competences as a physician. This study aims to discuss and investigates determinants of medical students’ empathy towards their patients during clinical rotation in the hospital. A qualitative study with phenomenology approach using focus group discussion (FGD) was accompanied with an open-ended questionnaire to serve as preliminary data and basis of FGD topic guidelines involved fourth and fifth grade medical students that has to pass one and/or two of these stages out of the 15 stages in clinical rotation. As much 191 students participated of the written questionnaire and 28 students agree upon voluntarily joining the FGD, which is held with a snowball sampling approach and finishes in five batches. The three main determinants are: i) Internal factors: knowledge about the importance of empathy, direct experience, personality, motivation, mood (emotion), and personal experience; ii) Patient’s and patient’s family factors: patient’s attitudes, patient’s family’s attitudes, patient’s socioeconomic status, patient's illness type and severity; and iii) Environment factors: burnout, satisfaction or appreciation in the job, work environment, and role models. Many factors influence medical students in expressing and implementing empathy as they are taught to do to their patients. Medical school as an institution responsible for upholding the professionalism and ethical standard can help to create more suitable environment for the students to ensure maximum learning experience.
Volume: 10
Issue: 3
Page: 629-637
Publish at: 2021-09-01

Reduction of total harmonic distortion of three-phase inverter using alternate switching strategy

10.11591/ijpeds.v12.i3.pp1598-1608
Nur Arifah Ramli , Auzani Jidin , Zulhani Rasin , Tole Sutikno
Alternating current (AC) electrical drives mainly require smaller current (or torque) ripples and lower total harmonic distortion (THD) of voltage for excellent drive performances. Normally, in practice, to achieve these requirements, the inverter needs to be operated at high switching frequency. By operating at high switching frequency, the size of filter can be reduced. However, the inverter which oftenly employs insulated gate bipolar transistor (IGBT) for high power applications cannot be operated at high switching frequency. This is because, the IGBT switching frequency cannot be operated above 50 kHz due to its thermal restrictions. This paper proposes an alternate switching strategy to enable the use of IGBT for operating the inverter at high switching frequency to improve THD performances. In this strategy, each IGBT in a group of switches in the modified inverter circuit will operate the switching frequency at one-fourth of the inverter switching frequency. The alternate switching is implemented using simple analog and digital integrated circuits.
Volume: 12
Issue: 3
Page: 1598-1608
Publish at: 2021-09-01
Show 915 of 1996

Discover Our Library

Embark on a journey through our expansive collection of articles and let curiosity lead your path to innovation.

Explore Now
Library 3D Ilustration