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29,922 Article Results

Optimal tuning of proportional integral controller for fixed-speed wind turbine using grey wolf optimizer

10.11591/ijece.v10i5.pp5251-5261
Aliyu Hamza Sule , Ahmad Safawi Mokhtar , Jasrul Jamani Bin Jamian , Attaullah Khidrani , Raja Masood Larik
The need for tuning the PI controller is to improve its performance metrics such as rise time, settling time and overshoot. This paper proposed the Grey Wolf Optimizer (GWO) tuning method of a Proportional Integral (PI) controller for fixed speed Wind Turbine. The objective is to overcome the limitations in using the PSO and GA tuning methods for tuning the PI controller, such as quick convergence occurring too soon into a local optimum, and the controller step input response. The GWO, the Particle Swarm Optimization (PSO), and the Genetic Algorithm (GA) tuning methods were implemented in the Matlab 2016b to search the optimal gains of the Proportional and Integral controller through minimization of the objective function. A comparison was made between the results obtained from the GWO tuning method against PSO and GA tuning techniques. The GWO computed the smallest value of the objective function minimized. It exhibited faster convergence and better time response specification compared to other methods. These and more performance indicators show the superiority of the GWO tuning method.
Volume: 10
Issue: 5
Page: 5251-5261
Publish at: 2020-10-01

Algorithm performance comparison for earthquake signal recognition on smartphone’s accelerometer

10.12928/telkomnika.v18i5.14708
Hapsoro Agung; School of Meteorology, Climatology, and Geophysics Nugroho , Haryas Subyantara; School of Meteorology, Climatology, and Geophysics Wicaksana , Hariyanto; School of Meteorology, Climatology, and Geophysics Hariyanto , Rista H.; School of Meteorology, Climatology, and Geophysics Virgianto
Micro-electro-mechanical-system accelerometer is able to detect acceleration signal caused by earthquake. Such type of accelerometer is also used by smartphones. There are few algorithms that can be used to recognize the type of acceleration signal from smartphone. This study aims to find signal recognition algorithm in order to consider the most proper algorithm for earthquake signal detection. The initial stage of designing the recognizer is data collection for each type of signal classification. The next step is to apply a highpass filter to separate the signals collected from the gravitational acceleration signal. The signal is divided into several segments. The system will extract features of each signal segment in the time and frequency domain. Each signal segment is then classified according to the type of signal using the classifier through a series of training data processes. The classifier which has the highest accuracy value is exported into the new input signal modeling. As the result, fine K-NN algorithm has the highest level of accuracy in the classification. The fine K-NN algorithm has an accuracy rate of 99.75% in the classification of human activity signals and earthquake signals with a memory capacity of 6,044 kilobytes and processing time of 15.93 seconds. This algorithm has the best classifier criteria compared to decision tree, support vector machine and linear discriminant analysis algorithms.
Volume: 18
Issue: 5
Page: 2505-2516
Publish at: 2020-10-01

Pulse shaping methods for inter carrier interference reduction in OFDM system

10.12928/telkomnika.v18i5.13840
N. M. A. E. D.; Udayana University Wirastuti , Ni Putu Lintang; Bali Towerindo Sentra Plc. Anggitiadewi , Nyoman; Udayana University Pramaita
The weakness of the orthogonal freuency division multiplexing (OFDM) system is susceptible to the existence of carrier frequency offset (CFO) which causes the emergence of inter carrier interference (ICI) which causes a degradation of performance OFDM systems. This study aims to apply the suggested rectangular (REC) pulse and improved sinc-power (ISP) pulse shaping methods on OFDM system and determines ICI reduction with the effects of CFO over flat fading Rayleigh channels. The performance of each pulse shaping method is evaluated and compared based on parameter ICI power vs. normalized frequency offset, signal to interference ratio (SIR) vs. normalized frequency offset and bit error rate (BER) vs. energy bit per noise (Eb/No). The simulation result in terms of BER vs. Eb/No indicated that REC and ISP pulse shaping has better performance dealing with ICI reduction compared to OFDM system no applied pulse shaping. In addition, the ISP is able to mitigate ICI better than REC.
Volume: 18
Issue: 5
Page: 2276-2283
Publish at: 2020-10-01

Creation of speech corpus for emotion analysis in Gujarati language and its evaluation by various speech parameters

10.11591/ijece.v10i5.pp4752-4758
Vishal P. Tank , S. K. Hadia
In the last couple of years emotion recognition has proven its significance in the area of artificial intelligence and man machine communication. Emotion recognition can be done using speech and image (facial expression), this paper deals with SER (speech emotion recognition) only. For emotion recognition emotional speech database is essential. In this paper we have proposed emotional database which is developed in Gujarati language, one of the official’s language of India. The proposed speech corpus bifurcate six emotional states as: sadness, surprise, anger, disgust, fear, happiness. To observe effect of different emotions, analysis of proposed Gujarati speech database is carried out using efficient speech parameters like pitch, energy and MFCC using MATLAB Software.
Volume: 10
Issue: 5
Page: 4752-4758
Publish at: 2020-10-01

Designing and configuring context-aware semantic web applications

10.12928/telkomnika.v18i5.15277
Haider Hadi; Al-Mansour University College (MUC) Abbas , Suha Sahib; Ministry of Higher Education Oleiwi , Haider Rasheed; Baghdad College of Economic Sciences University Abdulshaheed
Context-aware services are attracting attention of world as the use of web services are rapidly growing. We designed an architecture of context-aware semantic web which provides on demand flexibility and scalability in extracting and mining the research papers from well-known digital libraries i.e. ACM, IEEE and SpringerLink. This paper proposes a context-aware administrations system, which supports programmed revelation and incorporation of setting dependent on Semantic Web administrations. This work has been done using the python programming language with a dedicated library for the semantic web analysis named as “Cubic-Web” on any defined dataset, in our case as we have used a dataset for extracting and studying several publications to measure the impact of context aware semantic web application on the results. We have found the average recall and averge accuracy for all the context aware research journals in our research work. Moreover, as this study is limited journal documents, other future studies can be approached by examining different types of publications using this advance research. An efficient system has been designed considering the parameters of research article meta-data to find out the papers from the web using semantic web technology. Parameters like year of publication, type of publication, number of contributors, evaluation methods and analysis method used in publication. All this data has been extracted using the designed context-aware semantic web technology.
Volume: 18
Issue: 5
Page: 2549-2559
Publish at: 2020-10-01

The effectiveness of MgCeAl11O19:Tb3+ phosphor in enhancing the luminous efficacy and color quality of multi-chip white LEDs

10.11591/ijece.v10i5.pp4631-4638
Nguyen Thi Phuong Loan , Nguyen Doan Quoc Anh
In this research paper, we introduced yellow-green MgCeAl11O19:Tb3+ asa new phosphor ingredient to adapt to the quality requirements onthe chromatic homogeneity and emitted luminous flux of modern multi-chip white LED lights (MCW-LEDs). The results from experiments and simulation show that employing MgCeAl11O19:Tb3+ phosphor can lead to much better optical properties and therefore is a perfect supporting material to achieve the goals of the research. When the MgCeAl11O19:Tb3+ phosphor is added into the phosphorus composite which already contains YAG: Ce3+ particles, and the silicone glue, it affects the optical properties significantly. In other words, the concentration of this phosphor can determine the efficiency of lumen output and chromatic homogeneity of WLEDs. In specific, as the concentration of MgCeAl11O19:Tb3+ go up, the luminous yield will increase accordingly, though there is an insignificant decrease in CQS. Moreover, if the MgCeAl11O19:Tb3+ concentration reduce a little bit, it is possible to better the correlated color temperature uniformity and lumen efficacy of LED packages. In addition, the Mie scattering theory, Monte Carlo simulation and LightTools 8.3.2 software are employed to analyze and simulate the LED packages’ structure as well as the phosphor compound.
Volume: 10
Issue: 5
Page: 4631-4638
Publish at: 2020-10-01

The Effects of ZnO particles on the color homogeneity of phosphor-converted high-power white LED light sources

10.11591/ijece.v10i5.pp5155-5161
Nguyen Thi Phuong Loan , Nguyen Doan Quoc Anh
Color homogeneity is one of the goals to continuously improve WLED. Among the methods for enhancing the color uniformity of WLEDs, improving scattering in phosphor layer is considered to be the most effective. In this paper, ZnO is used for that purpose. The results show that ZnO particle size significantly affects scattering in the phosphor layer, which is a vital factor to analyze scattering, scattering sand surface, scattering coefficient and scattered phase function C_sca (D,λ), μ_sca (λ) and ρ(θ,λ). In addition, the concentration of ZnO was also analyzed with values from 2% to 22%. Color homogeneity depends not only on size but also on the concentration of added ZnO. Therefore, color homogeneity control is the control of ZnO size and concentration. The proposed result is 10% ZnO for the highest lumen of LED. With 14% and 500 nm of ZnO particles, ΔCCT reaches the lowest. Depending on the production needs, manufacturers can choose the most appropriate way. However, with both required lumen and ΔCCT, 14% ZnO is suitable for ZnO sizes.
Volume: 10
Issue: 5
Page: 5155-5161
Publish at: 2020-10-01

Factors influencing low intension detection rate in a non-invasive EEG-based brain computer interface system

10.11591/ijeecs.v20.i1.pp167-175
Clifford Maswanganyi , Chungling Tu , Pius Owolawi , Shengzhi Du
Motor imagery (MI) responses extracted from the brain in the form of EEG signals have been widely utilized for intention detection in brain computer interface (BCI) systems. However, due to the non-linearity and the non-stationarity of EEG signals, BCI systems suffer from low MI prediction rate with both known and unknown influncing factors. This paper investigates the impact of visual stimulus, feature dimensions and artifacts on MI task detection rate, towards improving MI prediction rate. Three EEG datasets were utilized to facilitate the investigation. Three filters (band-pass, notch and common average reference) and the independent component analysis (ICA) were applied on each datasets, to eliminate the impact of artifact. Three sets of features where extracted from artifact free ICA components, from which more relevant features were selected. Moreover, the selected feature subsets were incorporated into three classifiers, NB, Regression Tree and K-NN to predict four MI and hybrid tasks. K-NN classifier outperformed the other two classifies in each dataset. The highest classification accuracy is obtained in hybrid task EEG dataset. Moreover, accurately predicted EEG classes were applied to a robotic arm control.
Volume: 20
Issue: 1
Page: 167-175
Publish at: 2020-10-01

A novel delay dictionary design for compressive sensing-based time varying channel estimation in OFDM systems

10.12928/telkomnika.v18i5.14223
Maryam K.; Al-Nahrain University Abboud , Bayan M.; Al-Nahrain University Sabbar
Compressive sensing (CS) is a new attractive technique adopted for Linear Time Varying channel estimation. orthogonal frequency division multiplexing (OFDM) was proposed to be used in 4G and 5G which supports high data rate requirements. Different pilot aided channel estimation techniques were proposed to better track the channel conditions, which consumes bandwidth, thus, considerable data rate reduced. In order to estimate the channel with minimum number of pilots, compressive sensing CS was proposed to efficiently estimate the channel variations. In this paper, a novel delay dictionary-based CS was designed and simulated to estimate the linear time varying (LTV) channel. The proposed dictionary shows the suitability of estimating the channel impulse response (CIR) with low to moderate Doppler frequency shifts with acceptable bit error rate (BER) performance.
Volume: 18
Issue: 5
Page: 2284-2291
Publish at: 2020-10-01

Standalone photovoltaic array fed induction motor driven water pumping system

10.11591/ijece.v10i5.pp4534-4542
Atarsia Loubna , Toufouti Riad , Meziane Salima
Due to the absence of energy transmission lines connected to the water pumping sites in remote areas, problems related to the electrical power outages and the environmental degradation caused by fossil fuel. For this one of the most conceived solutions is the photovoltaic water pumping technology which has the advantage of being sustainable and respectful of the environment to supply water to rural areas. To ensure the need of water, especially for domestic use and small communities, in this article, the photovoltaic energy system for autonomous water pumping using the induction motor was presented, particularly adapted to the isolated regions. Pumping system consists of four photovoltaic (PV) panels, boost converter, inverter, induction motor, centrifugal pump and a storage tank. In this study, the output power of a PV solar cell is fully used by proposing the P&O algorithm, where it is used to follow a maximum power point tracking (MPPT) technique. The recommended system is designed, modeled and simulated on the MATLAB/Simulink platform. The efficiency of the proposed algorithm is observed with variable solar sunshine.
Volume: 10
Issue: 5
Page: 4534-4542
Publish at: 2020-10-01

Defective ground structure and complimentary split ring resonator loaded compact wideband antenna for radiolocation applications

10.12928/telkomnika.v18i5.15953
Nelapati Ananda; Acharya Nagarjuna University College of Engineering and Technology Rao , Siddaiah; Acharya Nagarjuna University College of Engineering and Technology P.
A wideband compact antenna with wo Bandwidth enhancement techniques intended for radiolocation applications is presented. Defective ground structure (DGS) is used to enhance the bandwidth and complimentary split ring resonator (CSRR) has been used to generate the bandwidth at the lower frequency of the antenna which brings compact nature. A coax feed patch antenna radiating at X-band frequency of 10 GHz is loaded with DGS and CSRR. Proposed antenna with a bandwidth of 3.4 GHz has shown a considerable enhancement in the antenna bandwidth when compared with the antenna with CSRR alone which is having a bandwidth of 1.15 GHz and a basic patch antenna whose bandwidth is 0.91 GHz. Proposed antenna is having omni directional radiation pattern with a gain of 5.01 dB and without any null in the coverage area. A great increase in the current fields can be observed that the field currents by loading the patch and ground with CSRR and DGS respectively. The patch currents have increased from 2.76 v/m to 3.25 v/m and the ground currents have increased from 0v/m to 2.45 v/m. Proposed antenna has been realized and its performance is measured using vector network analyzer, a near match in between the simulated result and measured result is observed.
Volume: 18
Issue: 5
Page: 2328-2334
Publish at: 2020-10-01

Accurate harmonic source identification using S-transform

10.12928/telkomnika.v18i5.5632
Mohd Hatta; Universiti Teknikal Malaysia Melaka Jopri , Abdul Rahim; Universiti Teknikal Malaysia Melaka Abdullah , Rony; Infineon Technologies AG Karim , Srete; University of Osijek Nikolovski , Tole; Universitas Ahmad Dahlan Sutikno , Mustafa; Universiti Teknikal Malaysia Melaka Manap
This paper introduces the accurate identification of harmonic sources in the power distribution system using time-frequency distribution (TFD) analysis, which is S-transform. The S-transform is a very applicable method to represent signals parameters in time-frequency representation (TFR) such as TFR impedance (ZTFR) and the main advantages of S-transform it can provide better frequency resolution for low frequency components and also offers better time resolution for high-frequency components. The identification of multiple harmonic sources are based on the significant relationship of spectral impedances (ZS) that extracted from the ZTFR, consist of the fundamental impedance (Z1) and harmonic impedance (Zh). To verify the accuracy of the proposed method, MATLAB simulations carried out several unique cases on IEEE 4-bus test feeder cases. It is proven that the proposed method is superior, with 100% correct identification of harmonic source location. It is proven that the method is accurate, fast and cost-efficient to localize harmonic sources in the power distribution system.
Volume: 18
Issue: 5
Page: 2708-2717
Publish at: 2020-10-01

Control system of automatic garage using programmable logic controller

10.12928/telkomnika.v18i5.14398
K.; SRM Institute of Science and Technology Selvakumar , R.; SRM Institute of Science and Technology Palanisamy , Patti; SRM Institute of Science and Technology Nikhil , D.; SRM Institute of Science and Technology Karthikeyan , D.; SRM Institute of Science and Technology Selvabharathi
In today’s populated world, urban land availability has become scarce and manual involvement of humans for a proper task makes a work less efficient and less accurate. The garage is one of the workstations which needs to be modernized for enhanced land utilization, energy saving approach and systematic functioning. This goal can only be achieved through the automation of parking systems. We have proposed an automated control system for garage using siemens PLC (programmable logic control)-1200 to control the vehicles. The number plate of the car is recorded through the RFID reader and the parking slot for that particular vehicle is allotted automatically based on the available vacancy. Along with this the parking area is fitted with fire alarm, which will raise if any smoke or fire happens in the location. The total parking cost of each vehicle can be calculated based on the number of hours it has been parked. And the information will be displayed in the SCADA screen. Additionally, instead of the full lightening of the complete place, lightening will be provided only in the direction of movement of the car, preventing wastage of energy.
Volume: 18
Issue: 5
Page: 2654-2664
Publish at: 2020-10-01

Hybrid order characteristics in car-following behavior

10.11591/ijeecs.v20.i1.pp158-166
Chunling Tu , Shengzhi Du
This paper addresses the discovery of an interesting property in car-following processes, which was not reported in the existing literatures. A hybrid order behavior is supported by both experimental data and theoretical simulations. To demonstrate this behavior, the first order and the second order car-following behaviors are defined. Then, by comparing the first and the second order car-following behaviors in the existing analystic models and the real traffic context, this paper finds that a significant amount of the second order car-following processes in real traffic context do not match the existing models and structural mismatches are observed. The popularity and significance of such cases suggest the existence of unmodelled dynamics in the existing methods, that is, the car following behavior should be determined by more factors than the immediate proceeding vehicle. Therefore, the existing car-following models must be improved to accommodate these factors. This forms one of the main values of this paper. This paper then defines the hybrid order car-following behavior and prompts to associate this behavior with the concerned unmodelled dynamics (mismatches between the actual traffic data and the simulation from models). The neural network is employed to model such dynamics. The idea of the proposed hybrid order behavior matches the fact that the car-following behavior is determined by multiple vehicles driving in front of the subject car instead of only the immediate proceeding one. This is valuable because it provides guidance on the improvement of existing car-following models. The neural network model validates that the consideration of multiple vehicles improves the accuracy of car-following modelling.
Volume: 20
Issue: 1
Page: 158-166
Publish at: 2020-10-01

Development of video-based emotion recognition using deep learning with Google Colab

10.12928/telkomnika.v18i5.16717
Teddy Surya; International Islamic University Malaysia Gunawan , Arselan; International Islamic University Malaysia Ashraf , Bob Subhan; Universitas Potensi Utama Riza , Edy Victor; Universitas Potensi Utama Haryanto , Rika; Universitas Potensi Utama Rosnelly , Mira; International Islamic University Malaysia Kartiwi , Zuriati; Universiti Teknologi MARA Janin
Emotion recognition using images, videos, or speech as input is considered as a hot topic in the field of research over some years. With the introduction of deep learning techniques, e.g., convolutional neural networks (CNN), applied in emotion recognition, has produced promising results. Human facial expressions are considered as critical components in understanding one's emotions. This paper sheds light on recognizing the emotions using deep learning techniques from the videos. The methodology of the recognition process, along with its description, is provided in this paper. Some of the video-based datasets used in many scholarly works are also examined. Results obtained from different emotion recognition models are presented along with their performance parameters. An experiment was carried out on the fer2013 dataset in Google Colab for depression detection, which came out to be 97% accurate on the training set and 57.4% accurate on the testing set.
Volume: 18
Issue: 5
Page: 2463-2471
Publish at: 2020-10-01
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