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The relationship between preschool teachers’ self-efficacy beliefs and their teaching attitudes

10.11591/ijere.v9i4.20670
Kamil Arif Kırkıç , Fatma Çetinkaya
This study examined the relationship between preschool teachers’ selfefficacy beliefs and their teaching attitudes. In the study, it was considered whether preschool teachers’ self-efficacy beliefs and their teaching attitudes change in terms of certain variables. The research was carried out using a correlational survey model. The target population of the study is the preschool teachers working in Küçükçekmece district, İstanbul Province, in the 2017-2018 academic year. The working group consists of 264 preschool teachers working at the schools in said district. The following assessment instruments were used in the research: “Personal Information Form,” “Preschool Teachers’ Self-efficacy Beliefs Scale,” to identify preschool teachers’ self-efficacy beliefs and ‘Preschool Teachers’ Teaching Attitudes Scale’ to determine the teachers’ attitudes. The obtained data were analyzed using Pearson multiplication moment correlation analysis, and Regression analysis was performed to determine the level of self-efficacy beliefs of preschool teachers affecting teaching attitudes. Preschool teachers were found to have full self-efficacy beliefs in the teaching-learning process, communication skills, planning, and regulation of learning environments and classroom management, and firm self-efficacy beliefs in family participation. Teachers’ attitudes of preschool teachers were found to be democratic at the highest level, followed by autocratic and laissez-faire at the lowest level. As a result of the regression analysis made to determine the level of the effect of self-efficacy beliefs of preschool teachers on their teaching attitudes, the learning and teaching process positively predicts democratic teaching attitudes and negatively predicts laissez-faire attitudes.
Volume: 9
Issue: 4
Page: 807-815
Publish at: 2020-12-01

Design, modelling and simulation of controlled sepic DC-DC converter-based genetic algorithm

10.11591/ijpeds.v11.i4.pp2116-2125
Mohammed Omar Ali , Ali Hussein Ahmad
This paper discusses various aspects of a single-ended primary inductance DC-DC converter (SEPIC). The focus is on design, modelling, and simulation results of a SEPIC converter. The study analyses the principle of SEPIC operation when operated in continuous conduction mode (CCM). Additionally, the mathematical equations for the design modules are calculated as per converter requirements. State-space equations are used to formulate the state-space model of the SEPIC converter. To satisfy the best-performance criterion of the system, the parameters for controller (Kp, Ki, Kd) should be tuned or optimized using the genetic algorithm (GA) optimization technique. Controller parameters are determined using an objective function that minimises the integral time absolute error (ITAE). Simulations performed on a closed-loop system reveal that the step response with a PID controlled based GA displayed superior performance. A closed-loop system has a substantially bigger stability region compared to an open-loop system. The simulation optimised performance metrics like maximum overshoot percentage (Mp), rise time (tr), and settling time (ts). MATLAB/Simulink R2018a® and m-file code are used for the system modelling, simulation, and optimization of the PID controller parameters based on the GA.
Volume: 11
Issue: 4
Page: 2116-2125
Publish at: 2020-12-01

Design of high performance DC motor actuated cable driving system for compact devices

10.11591/ijpeds.v11.i2.pp580-593
Chawaphol Direkwatana , Jackrit Suthakorn
The cable transmission is widely used in the remote operation or complex geometry with high stiffness and low backlash. Larger drum is required to reduce and error of transmission in long stroke. An error of the desired position occurs due to the fleet angle while cable winding on a drum. Therefore, a new cable driving module which overcomes this problem is proposed. A new cable driving module with a sliding platform is connected to the actuator unit. A motion of the sliding platform is corresponding to a screw rod connected to an actuator. The precision of the driving system is measured by a high-resolution rotatory encoder and high gear ratio actuator. Results are measured by load and error of the system. A load of system shows a performance of overall translation and rotation of the drum at different speeds. An error of the system is measured from forward and reverse direction by increasing and decreasing the number of turns with constant speed. A system has an average load consumption along a long stroke of cable winding which has no significant problem on the screw platform. Multiple turns have low error value in specific and continuous turn in forward and reverse motion. A new cable driving system is proved in precision movement. The fleet angle is eliminated in new mechanism. Along with a constraint motion, there is no significant change in load consumption. An error is low value in a different direction of movement. Hence, a new design of cable transmission can perform in high performance and small size of the system.
Volume: 11
Issue: 2
Page: 580-593
Publish at: 2020-12-01

Investigation on the BER performance of downlink JT-CoMP-NOMA with different modulation schemes

10.11591/ijeecs.v20.i3.pp1309-1314
Norshidah Katiran , Shaharil Mohd Shah , Noorsaliza Abdullah , Aimi Syamimi Abdul Ghaffar , Faiz Asraf Saparudin
The principle of joint transmission coordinated multipoint with non-orthogonal multiple access (JT-CoMP-NOMA) is to allow multiple cells in the network to cooperatively transmit data to users using the same network resources in frequency and time domains. The approach would be beneficial in enhancing the system performance in the context of spectral efficiency. This paper presents the performance comparison of JT-CoMP-NOMA for several modulation schemes including QPSK, 16-QAM and 64 QAM in downlink transmission in the context of bit error rate. We conduct an investigation to compare the error performance of JT-CoMP-NOMA with NOMA system. Our simulation results demonstrate that the JT-CoMP-NOMA provides lower bit error rate compared to NOMA system.
Volume: 20
Issue: 3
Page: 1309-1314
Publish at: 2020-12-01

Automatic amyotrophic lateral sclerosis detection using tunable Q-factor wavelet transform

10.11591/ijai.v9.i4.pp744-756
Abdelouahad Achmamad , Abdelali Belkhou , Atman Jbari
Early diagnosis of amyotrophic lateral sclerosis (ALS) based on electromyography (EMG) is crucial. The processing of a non-stationary EMG signal requires powerful multi-resolution methods. Our study analyzes and classifies the EMG signals. In the present work, we introduce a novel flexible method for classification of EMG signals using tunable Q-factor wavelet transform (TQWT). Different sub-bands generated by the TQWT technique were served to extract useful information related to energy and then the calculated features were selected using a filter selection (FS) method. The effectiveness of the feature selection step resulted not only in the improvement of classification performance but also in reducing the computation time of the classification algorithm. The selected feature subsets were used as inputs to multiple classifier algorithms, namely, k-nearest neighbor (k-NN), least squares support vector machine (LS-SVM) and random forest (RF) for automated diagnosis. The experimental results show better classification measures with k-NN classifier compared with LS-SVM and RF. The robustness of the classification task was tested using a ten-fold cross-validation method. The outcomes of our proposed approach can be exploited to aid clinicians in neuromuscular disorders detection.
Volume: 9
Issue: 4
Page: 744-756
Publish at: 2020-12-01

PSO-CCO_MIMO-SA: A particle swarm optimization based channel capacity optimzation for MIMO system incorporated with smart antenna

10.11591/ijece.v10i6.pp6276-6282
Shivapanchakshari T. G. , H. S. Aravinda
With the radio channels physical limits, achieving higher data rate in the multi-channel systems is been a biggest concern. Hence, various spatial domain techniques have been introduced by incorporating array of antenna elements (i.e., smart antenna) in recent past for the channel limit expansion in mobile communication antennas. These smart antennas help to yield the improved array gain or bearm forming gain and hence by power efficiency enhanmaent in the channel and antenna range expansion. The use of smart antenna leads to spatial diversity and minimizes the fading effect and improves link reliability. However, in the process of antenna design, the proper channel modelling is is biggest concern which affect the wireless system performance. The recent works of MIMO design systems have discussed the issues in number of antenna selection which suggests that optimization of MIMO channel capacity is required. Hence, a Particle Swarm Optimization based channel capacity optimzation for MIMO system incorporated with smart antenna is introduced in this paper. From the outcomes it is been found that the proposed PSO based MIMO system achieves better convergenece speed which results in better channel capacity.
Volume: 10
Issue: 6
Page: 6276-6282
Publish at: 2020-12-01

A lightweight secure CoAP for IoT-cloud paradigm using elliptic-curve cryptography

10.11591/ijeecs.v20.i3.pp1460-1470
Amrani Ayoub , Rafalia Najat , Abouchabaka Jaafar
Cloud computing and the internet of things (IoT), two different technologies, are already part of our lives. Their impressive adoption increasing more and more, which makes them the future of the future internet. The tsunami of interconnectivity between objects and data collection is increasingly based on Cloud Computing, where data analysis and intelligence really reside. A new paradigm where the Cloud and the IoT are merged will create a new air in the world of technology, which can offer many services and applications useful to humanity. However, despite the great benefits that can bring this technology in term of new services, elasticity and flexibility, the security aspect still remains a serious constraint which hampers the expansion of this technology. This paper proposes a lightweight Mutual authentication protocol based on constrained application protocol (CoAP); that is suitable for IoT device than HTTP and using elliptic curve cryptography to secure data transmission between the Cloud and devices. We used AVISPA tool to verify our proposed scheme.
Volume: 20
Issue: 3
Page: 1460-1470
Publish at: 2020-12-01

Cyber DoS attack based security simulator for VANET

10.11591/ijece.v10i6.pp5832-5843
Muntadher Naeem Yasir , Muayad Sadik Croock
At the late years, researches focused on the cyber Denial of Service (DoS) attacks in the Vehicle Ad hoc Networks (VANETS). This is due to high importance of ensuring the save receiving of information in terms of Vehicle to Vehicle (V2V), Vehicle to Infrastructure (V2I) and Vehicle to Road Side Unit (V2R). In this paper, a cyber-security system is proposed to detect and block the DoS attacks in VANET. In addition, a simulator for VENAT based on lightweight authentication and key exchange is presented to simulate the network performance and attacks. The proposed system consists of three phases: registration, authentication as well as communications and DoS attack detection. These phases improve the system ability to detect the attacks in efficient way. Each phase working is based in a proposed related algorithm under the guidance of lightweight protocol. In order to test the proposed system, a prototype is considered includes six cars and we adopt police cars due to high importance of exchanged information. Different case studies have been considered to evaluate the proposed system and the obtained results show a high efficiency of performance in terms of information exchange and attack detection.
Volume: 10
Issue: 6
Page: 5832-5843
Publish at: 2020-12-01

Hybrid technique for an efficient PV system through intelligent MPPT and water cooling process

10.11591/ijpeds.v11.i4.pp1835-1843
Hussain Attia , Khaled Hossin
Solar panels have undergone several tests through research studies for the purpose of improving performance to increase the resulting electrical power. This study considers the fact of the necessity of Maximum Power Point Tracking working conditions of the PV panels to harvest maximum electrical power during the weather variations. It considers also the panel temperature reduction which affects positively the panel ability in terms of producing additional electrical power. By this consideration, this study proposes a new design, and simulation results with analysis of a hybrid PV system. The system is able to deliver 5 kW, through the day hours, with less number of PV panels based on a hybrid technique. The proposed technique combines two manipulating processes. The first one guarantees the Maximum Power Point Tracking (MPPT) condition during day hours through an artificial Neural Network (ANN) controller. Whereas the second one focuses on reducing the panel temperature by introducing a water cooler which is designed for this purpose. Simulink software of MATLAB is used to implement and evaluate the proposed system.
Volume: 11
Issue: 4
Page: 1835-1843
Publish at: 2020-12-01

Hybrid unified power quality conditioner for power quality enhancement

10.11591/ijpeds.v11.i4.pp2126-2134
Djellouli Djoudi , Benoudjafer Cherif , Toumi Toufik , Othmane Abdelkhalek
In a low-voltage electrical network, harmonics, reactive power, the current and voltage imbalance, and voltage dips have harmful effects on electrical equipments. To overcome these problems, the hybrid UPQC is proposed. This paper discusses the structure of passive filters, parallel active filters, serial and combines (UPQC) to study the compensation of all types of disturbances likely to appear in the grid. Furthermore, the aim of reducing the size, cost of UPQC is to improve the quality of electric power, making it in compliance with the new regulatory constraints, we proposed the hybrid UPQC which uses passive filters and a combination of active filters. To validate the proposed topology, several sags of source voltage have been applied, at the point of common coupling (PCC). The simulation results from MATLAB/Simulink are discussed to verify the proposed topology.
Volume: 11
Issue: 4
Page: 2126-2134
Publish at: 2020-12-01

Intelligent control of flywheel energy storage system associated with the wind generator for uninterrupted power supply

10.11591/ijpeds.v11.i4.pp2062-2072
Bensaid Amel , Zebirate Soraya , Chaker Abdelkader
Wind energy is currently the fastest-growing energy source in the world. However, the inherent characteristic of intermittent energy production, due to the stochastic nature of wind, still comprises the main drawback of wind power. To avoid such problems, various configurations have been reccomended in order to reduce output power variation. The paper concentrates on performance benefits of adding energy storage system with the wind generator in order to regulate the electric power delivered into the power grid. Compared with other means of energy storage, the flywheel energy storage system (FESS) is the best choice to solve power quality problems. In this paper, a FESS associated to a variable speed wind generation (VSWG) is investigated by presenting two control strategies applied to the storage system equipped with an induction machine; both techniques are studied and developed and consist of a field control (FOC) and a Fuzzy Logic Control (FLC). Simulation model is established in MATLAB/Simulink and comparative results are then reported.
Volume: 11
Issue: 4
Page: 2062-2072
Publish at: 2020-12-01

Hybrid compensation of polarization-multiplexed QPSK optical format for high bit rate networks

10.11591/ijeecs.v20.i3.pp1325-1331
Omar Y. Shabaan , Omar A. Athab
Transmitting the highest capacity throughput over the longest possible distance without any regeneration stage is an important goal of any long-haul optical network system. Accordingly, polarization-multiplexed quadrature phase-shift-keying (PM-QPSK) was introduced lately to achieve high bit-rate with relatively high spectral efficiency. Unfortunately, the required broad bandwidth of PM-QPSK increases the linear and nonlinear impairments in the physical layer of the optical fiber network. Increased attention has been spent to compensate for these impairments in the last years. In this paper, single mode fiber (SMF), single channel, PM-QPSK transceiver was simulated, with a mix of optical and electrical (digital signal processing (dsp) compensation stages to minimize the impairments  The behaviour of the proposed system was investigated under four conditions: without compensation, with only optical compensator, with only DSP compensator and finally with both compensators. An evidence improvement was noticed in the case of hybrid compensation; where the transmission distance was multiplied from (720 km) to more than (3000 km) at 40 Gb/s.
Volume: 20
Issue: 3
Page: 1325-1331
Publish at: 2020-12-01

A new hybrid text encryption approach over mobile ad hoc network

10.11591/ijece.v10i6.pp6461-6471
Mohammed Amin Almaiah , Ziad Dawahdeh , Omar Almomani , Adeeb Alsaaidah , Ahmad Al-Khasawneh , Saleh Khawatreh
Data exchange has been rapidly increased recently by increasing the use of mobile networks. Sharing information (text, image, audio and video) over unsecured mobile network channels is liable for attacking and stealing. Encryption techniques are the most suitable methods to protect information from hackers. Hill cipher algorithm is one of symmetric techniques, it has a simple structure and fast computations, but weak security because sender and receiver need to use and share the same private key within a non-secure channel. Therefore, a novel hybrid encryption approach between elliptic curve cryptosystem and hill cipher (ECCHC) is proposed in this paper to convert Hill Cipher from symmetric technique (private key) to asymmetric one (public key) and increase its security and efficiency and resist the hackers. Thus, no need to share the secret key between sender and receiver and both can generate it from the private and public keys. Therefore, the proposed approach presents a new contribution by its ability to encrypt every character in the 128 ASCII table by using its ASCII value direct without needing to assign a numerical value for each character. The main advantages of the proposed method are represented in the computation simplicity, security efficiency and faster computation.
Volume: 10
Issue: 6
Page: 6461-6471
Publish at: 2020-12-01

Development of algorithm for identification of maligant growth in cancer using artificial neural network

10.11591/ijece.v10i6.pp5709-5713
R. Pandian , D.N.S. Ravi Kumar , R. Raja Kumar
The precise identification and characterization of small pulmonary nodules at low-dose CT is a necessary requirement for the completion of valuable lung cancer screening. It is compulsory to develop some automated tool, in order to detect pulmonary nodules at low dose ct at the beginning stage itself. The numerous algorithms had been proposed earlier by many researchers in the past, but, the accuracy of prediction is always a challenging task. In this work, an artificial neural network based methodology is proposed to find the irregular growth of lung tissues. Higher probability of detection is taken as a goal to get an automated tool, with great accuracy. The finest feature sets derived from Haralick Gray level co occurrence Matrix and used as the dimension reduction way for feeding neural network. In this work, a binary Binary classifier neural network has been proposed to identify the normal images out of all the images. The capability of the proposed neural network has been quantitatively computed using confusion matrix and found in terms of classification accuracy.
Volume: 10
Issue: 6
Page: 5709-5713
Publish at: 2020-12-01

Power loss reduction by gryllidae optimization algorithm

10.11591/ijict.v9i3.pp179-184
Kanagasabai Lenin
This paper projects Gryllidae Optimization Algorithm (GOA) has been applied to solve optimal reactive power problem. Proposed GOA approach is based on the chirping characteristics of Gryllidae. In common, male Gryllidae chirp, on the other hand some female Gryllidae also do as well. Male Gryllidae draw the females by this sound which they produce. Moreover, they caution the other Gryllidae against dangers with this sound. The hearing organs of the Gryllidae are housed in an expansion of their forelegs. Through this, they bias to the produced fluttering sounds. Proposed Gryllidae Optimization Algorithm (GOA) has been tested in standard IEEE 14, 30 bus test systems and simulation results show that the projected algorithms reduced the real power loss considerably.
Volume: 9
Issue: 3
Page: 179-184
Publish at: 2020-12-01
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