TELKOMNIKA (Telecommunication Computing Electronics and Control)

Journal Information
ISSN / EISSN : 1693-6930 / 2302-9293
Current Publisher: Universitas Ahmad Dahlan (10.12928)
Total articles ≅ 2,649
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Latest articles in this journal

W. S. W. Daud, N. Ahmad, G. Malkawi
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 583-598; doi:10.12928/telkomnika.v19i2.18023

Matrix equations have its own important in the field of control system engineering particularly in the stability analysis of linear control systems and the reduction of nonlinear control system models. There are certain conditions where the classical matrix equation are not well equipped to handle the uncertainty problems such as during the process of stability analysis and reduction in control system engineering. In this study, an algorithm is developed for solving fully fuzzy matrix equation particularly for ~ A ~X ~B 􀀀 ~X = ~ C, where the coefficients of the equation are in near-zero fuzzy numbers. By modifying the existing fuzzy multiplication arithmetic operators, the proposed algorithm exceeds the positive restriction to allow the near-zero fuzzy numbers as the coefficients. Besides that, a new fuzzy subtraction arithmetic operator has also been proposed as the existing operator failed to satisfy the both sides of the nearzero fully fuzzy matrix equation. Subsequently, Kronecker product and V ec-operator are adapted with the modified fuzzy arithmetic operator in order to transform the fully fuzzy matrix equation to a fully fuzzy linear system. On top of that, a new associated linear system is developed to obtain the final solution. A numerical example and the verification of the solution are presented to demonstrate the proposed algorithm.
Mohammad Tariq Yaseen, Abdalem A. Rasheed
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 683-689; doi:10.12928/telkomnika.v19i2.18146

The plasmonic material properties of aluminum allow active plasmon resonances extending from the blue color in the visible range to the ultraviolet (UV) region of the spectrum. Whereas Al is usually avoided for applications of plasmonics due to its losses in the infrared spectrum region. In this work, the study of the scatter and absorption of disk nanoantennas (DNAs) using various types of materials Au, Ag, and Al is accomplished by using the CST microwave studio suite simulation. The results showed that Al can offer good plasmonic properties when DNA radius is 25 nm to 125 nm at 20 nm height and working wavelengths longer than 800 nm in the near-infrared (NIR) region. Al produces negative plasmonic features around 800 nm wavelength due to the interband transition in the imaginary part of epsilon. For Au and Ag, the plasmonic characteristics rapidly decayed when the DNA radius was higher than 60 nm, but in contrast, Al offers good plasmonic features at these large dimensions of DNAs. This extended response of Al in UV, visible, and NIR, incorporated with its low cost, natural abundance, low native oxide, and amenability to industrial processes, could make Al an extremely promising plasmonic metal candidate for energy applications.
Arwa H. Salih Hamdany, Aseel Thamar Ebrahem, Ahmed M. Alkababji
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 432-437; doi:10.12928/telkomnika.v19i2.16572

Earprint has interestingly been considered for recognition systems. It refers to the shape of ear, where each person has a unique shape of earprint. It is a strong biometric pattern and it can effectively be used for authentications. In this paper, an efficient deep learning (DL) model for earprint recognition is designed. This model is named the deep earprint learning (DEL). It is a deep network that carefully designed for segmented and normalized ear patterns. IIT Delhi ear database (IITDED) version 1.0 has been exploited in this study. The best obtaining accuracy of 94% is recorded for the proposed DEL.
Pakpoom Mookdarsanit, Lawankorn Mookdarsanit
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 479-490; doi:10.12928/telkomnika.v19i2.18321

Rice is a staple food for around 3.5 billion people in eastern, southern and south-east Asia. Prior to being rice, the rice-grain (grain) is previously husked and/or milled by the milling machine. Relevantly, the grain quality depends on its pureness of particular grain specie (without the mixing between different grain species). For the demand of grain purity inspection by an image, many researchers have proposed the grain classification (sometimes with localization) methods based on convolutional neural network (CNN). However, those papers are necessary to have a large number of labeling that was too expensive to be manually collected. In this paper, the image augmentation (rotation, brightness adjustment and horizontal flipping) is appiled to generate more number of grain images from the less data. From the results, image augmentation improves the performance in CNN and bag-of-words model. For the future moving forward, the grain recognition can be easily done by less number of images.
Aulia Aulia, Eka Putra Waldi, Darwison Darwison, Dwi Gustiono, Novizon Novizon, M. Heru Setiawan, M. A. Hafizi
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 631-637; doi:10.12928/telkomnika.v19i2.16417

The dielectric properties of low-density polyethylene natural rubber (LDPE-NR) biopolymeric insulating materials can be improved by adding the silica nanoparticles in a certain percentage of weight (w%). In the present study, four types of bio-nano polymeric samples were prepared. To each sample, the nanosilica particles with wt% 1.5%, 3%, 4.5% and 6%. As one characteristic of dielectric, the partial discharge (PD) characteristics, each sample has been tested for 1 hour under AC high voltage field, and the pulses were counted for each sample and grouped into positive and negative pulses. The PD pattern was also plotted based on X-Y axes, namely Φ-q-n pattern. It was found that the number of positive and negative partial discharge (PD) pulses for each silica sample after 60 minutes of testing varied for all samples. It is also found that samples with a higher percentage of nanosilica had fewer PD pulses. The PD pattern in lower w% of silica was identified in the 90 degrees mostly in containing This indicates that w% of nanosilica particles can improve the PD resistance or the insulation quality of LDPE-NR insulation materials.
Meryam Telmem, Youssef Ghanou
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 515-522; doi:10.12928/telkomnika.v19i2.16793

In this paper, we present an approach based on convolutional neural networks to build an automatic speech recognition system for the Amazigh language. This system is built with TensorFlow and uses mel frequency cepstral coefficient (MFCC) to extract features. In order to test the effect of the speaker's gender and age on the accuracy of the model, the system was trained and tested on several datasets. The first experiment the dataset consists of 9240 audio files. The second experiment the dataset consists of 9240 audio files distributed between females and males’ speakers. The last experiment 3 the dataset consists of 13860 audio files distributed between age 9-15, age 16-30, and age 30+. The result shows that the model trained on a dataset of adult speaker’s age +30 categories generates the best accuracy with 93.9%.
My Hanh Nguyen Thi, Phung Ton That, Hoang Van Ngoc
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 616-622; doi:10.12928/telkomnika.v19i2.16706

If remote phosphor structures are put into comparison with conformal phosphor or in-cup phosphor, their luminous flux are better, but the color quality is not as elevated. This leads to an obvious need of a practical solution to enhance color quality. Therefore, many studies were carried out to achieve this purpose, and so is ours. We proposed using two layers of phosphor in WLEDs to achieve better rendering ability and chromatic performance. The identical WLEDs with different color temperatures, 5600 K-8500 K, were used and reported in this paper. Our research consists of two parts, which are placing a layer of red phosphor SrwFxByOz:Eu2+,Sm2+on the yellow YAG:Ce3+ phosphor layer at first, and then specifying an appropriate SrwFxByOz:Eu2+,Sm2+ concentration to reach the highest color performance. It is shown that with the contribution of SrwFxByOz:Eu2+,Sm2+,the color rendering index (CRI) and color quality scale (CQS) are increased. This can be explained by the increased amount of red light components in the WLEDs when the concentration of SrwFxByOz:Eu2+,Sm2+ was greater. However, excessive SrwFxByOz:Eu2+,Sm2+ will cause the reduction in the flux, which has been proven by the application of Mie scattering and the Lambert-Beer law. Therefore, the conclusion will present an optimal amount of SrwFxByOz:Eu2+,Sm2+ to obtain high color quality while minimizing the light loss.
Ayom Widipaminto, Yohanes Fridolin Hestrio, Yuvita Dian Safitri, Donna Monica, Dedi Irawadi, Rokhmatuloh Rokhmatuloh, Djoko Triyono, Erna Sri Adiningsih
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 690-704; doi:10.12928/telkomnika.v19i2.18155

The current urban environment is very dynamic and always changes both physically and socio-economically very quickly. Monitoring urban areas is one of the most relevant issues related to evaluating human impacts on environmental change. Nowadays remote sensing technology is increasingly being used in a variety of applications including mapping and modeling of urban areas. The purpose of this paper is to classify the Pleiades data for the identification of roof materials. This classification is based on data from satellite image spectroscopy results with very high resolution. Spectroscopy is a technique for obtaining spectrum or wavelengths at each position from various spatial data so that images can be recognized based on their respective spectral wavelengths. The outcome of this study is that high-resolution remote sensing data can be used to identify roof material and can map further in the context of monitoring urban areas. The overall value of accuracy and Kappa Coefficient on the method that we use is equal to 92.92% and 0.9069.
M. M. Hasan Mahfuz, Shazzadul Islam, Islam Md. Rafiqul, Mohamed Hadi Habaebi, Nazmus Sakib
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 357-363; doi:10.12928/telkomnika.v19i2.18147

Recently lower frequency band 4.5−5.5 GHz is proposed by the ASEAN countries for 5G cellular application and therefore, it is essential of designing an ultra-wideband (UWB) antenna for the particular band-notched characteristics. In this article, a compact tuning fork shape ultra-wideband (UWB) patch antenna with a variable band-notched characteristic has been proposed for 5G cellular application. The UWB antenna has been achieved by using a tuning fork shape with a simple partial ground plane. A pair of ring shape slits (RSS) on the ground plane has been added to achieve the band-notched characteristic. The proposed antenna has achieved a large −10 dB bandwidth of 7.8 GHz (2.9−11 GHz) and the VSWR value is less than 2 for the entire bandwidth excepted for notched frequency bands of lower 5G bands (4.5−5.5 GHz). Moreover, the antenna has a peak radiation efficiency of more than 87% for UWB and less than 27% for the notched frequency band. The notched-band is shifted with the change in the position of RSS’s within the vertical axis and thus, the variable band-notched characteristics have been achieved. Besides, the proposed antenna is compact with the dimension of 45×34 mm2 that makes it suitable for the lower band of 5G application.
My Hanh Nguyen Thi, Phung Ton That
TELKOMNIKA (Telecommunication Computing Electronics and Control), Volume 19, pp 599-602; doi:10.12928/telkomnika.v19i2.16755

TiO2 nanoparticle and silicon composite has powerful effect of scattering, thus it is famous in enhancing the scattered light in light-emitting diode (LED) packages. To accomplish higher lighting performance in LED devices, a thin encapsulation layer of TiO2 with high concentration and silicon glue is introduced to complement the main encapsulation one. After conducting experiments, the results present that in the case of the main encapsulation including only silicone, the light extraction efficiency (LEE) of COB LEDs increases to 65%. On the other hand, when there is the additional layer of TiO2 and silicone, the improvement of LEE depends on the concentration of TiO2. As this nanoparticle concentration decreases from 0.12 to 0.035 g/cm3, the LEE can be enhanced from 6% to 24%. Moreover, at the average correlated color temperature (CCT) of approximately 8500 K, the layer of TiO2/silicone composite can help to accomplish the reduction of the angular correlated color temperature (CCT) deviation, from 900 to 470 K, within −90° to 90° viewing angle range.
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