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Rogowski coil sensor in the digitization process to detect partial discharge

10.12928/telkomnika.v18i2.14282
Eka Putra; Universitas Andalas Waldi , Asri Indah; Universitas Andalas Lestari , Rudy; Universitas Andalas Fernandez , Syaifa; Universitas Andalas Mulyadi , Yoshinobu; Toyohashi University of Technology Murakami , Naohiro; Toyohashi University of Technology Hozumi
This paper presents the construction of a Rogowski Coil sensor with an air core to detect partial discharge using a digital oscilloscope. Two types of sensors are used. The first is the primary sensor winding with back wire, and the second is without back wire, labeled BW and WBW, respectively. The numbers of primary-turn in the sensors are 5, 10, 20, and 40 turns. The performance of the sensors is tested using two types of tests. First, the wave response test with a fixed imitation partial discharge magnitude input is used to select the optimum sensitivity with the lower sampling rate, aims to select the peak or valley value as a magnitude partial discharge value. The second test is using an imitation partial discharge ramp to check the linearity of the sensors. The imitation of the partial discharge inputs is generated by a commercial charge calibrator. The wave response test results show an increase in the number of turns that corresponds to an increase of the sensor output for both sensors in a non-linear trend. In determining the sampling rate, the detection of magnitude in the valley is better than the peak. All sensors act linear toward the imitation partial discharge ramp either in BW or WBW conditions.
Volume: 18
Issue: 2
Page: 1062-1071
Publish at: 2020-04-01

Forecasting rupiah exchange rate with learning vector quantization neural network

10.11591/ijeecs.v18.i1.pp24-31
Linawati Linawati , Made Sudarma , I Putu Oka Wisnawa
The classification technique and data forecasting will probably be one of the techniques that will often be needed in handling or managing big data. So, from that the author analyzes the possible development of the existing algorithms. The purpose is to find possibilities in the use of reliable algorithms in a particular field, then can be adopted and implemented to develop forecasting techniques in the future. Based on these considerations, the authors conducted experiments by applying LVQNN to conduct shortterm forecasting on daily period of the Rupiah exchange rate. The literature that is used as a reference is the discovery of architectural data classification processes that resemble forecasting techniques. So, when there is a combination of Rupiah exchange histories, it is possible to find these combinations into certain classes based on predetermined parameters and historical data combination data and forecast values in the past. In this research the factors chosen as indicators that affect the Rupiah exchange rate are the amount of exports, the amount of imports, the inflation rate and also the world oil price. In this research the highest accuracy value in the testing process for the population reached 99.0991%. The increase in the percentage value of forecasting accuracy is influenced by the composition of the data. In this study the formation of data composition is influenced by distinct data. The selection of parameters which become distinct claused determines how the composition of the data will be formed. If the composition of the data is not correct, the test results will not be good. If the number of weights vector is smaller than the input data, the forecasting accuracy will decrease. Because the weight vector cannot represent data combinations that used during training or testing.
Volume: 18
Issue: 1
Page: 24-31
Publish at: 2020-04-01

HAR-MI method for multi-class imbalanced datasets

10.12928/telkomnika.v18i2.14818
H.; STMIK IBBI Hartono , Yeni; STMIK IBBI Risyani , Erianto; Akademi Teknologi Industri Immanuel Ongko , Dahlan; Universitas Malikussaleh Abdullah
Research on multi-class imbalance from a number of researchers faces obstacles in the form of poor data diversity and a large number of classifiers. The Hybrid Approach Redefinition-Multiclass Imbalance (HAR-MI) method is a Hybrid Ensembles method which is the development of the Hybrid Approach Redefinion (HAR) method. This study has compared the results obtained with the Dynamic Ensemble Selection-Multiclass Imbalance (DES-MI) method in handling multiclass imbalance. In the HAR-MI Method, the preprocessing stage was carried out using the random balance ensembles method and dynamic ensemble selection to produce a candidate ensemble and the processing stages was carried out using different contribution sampling and dynamic ensemble selection to produce a candidate ensemble. This research has been conducted by using multi-class imbalance datasets sourced from the KEEL Repository. The results show that the HAR-MI method can overcome multi-class imbalance with better data diversity, smaller number of classifiers, and better classifier performance compared to a DES-MI method. These results were tested with a Wilcoxon signed-rank statistical test which showed that the superiority of the HAR-MI method with respect to DES-MI method.
Volume: 18
Issue: 2
Page: 822-829
Publish at: 2020-04-01

Performance evaluation of the IEEE 802.11n random topology WLAN with QoS application

10.11591/ijece.v10i2.pp1924-1934
Ziyad Khalaf Farej , Mustafa Mohammad Jasim
The IEEE 802.11n supports high data rate transmissions due its physical layer Multiple Input ‎Multiple Output (MIMO) advanced antenna system and MAC layer enhancement features (frame ‎aggregation and block acknowledgement). As a result this standard is very suitable for multimedia ‎services through its Enhanced Distributed Channel Access (EDCA). This paper focuses on ‎evaluating the Quality of Service (QoS) application on the performance of the IEEE 802.11n ‎random topology WLAN. Three different number of nodes (3, 9 and 18) random topology with one ‎access point are modeled and simulated by using the Riverbed OPNET 17.5 Modular to ‎investigate the Wireless Local Area Network (WLAN) performance for different spatial streams. ‎The result clarified the impact of QoS application and showed that its effect is best at the 18 node ‎number topology. For a 4x4 MIMO, when QoS is applied and with respect to the no QoS ‎application case, simulation results show a maximum improvement of 86.4%, 33.9%, 52.2% and ‎‎68.9% for throughput, delay, data drop and retransmission attempts, respectively. ‎
Volume: 10
Issue: 2
Page: 1924-1934
Publish at: 2020-04-01

Enabling relay selection in non-orthogonal multiple access networks: direct and relaying mode

10.12928/telkomnika.v18i2.13313
Dinh-Thuan; Industrial University of Ho Chi Minh City (IUH) Do , Minh-Sang V.; Industrial University of Ho Chi Minh City (IUH) Nguyen
In this paper, we consider downlink non-orthogonal multiple access (NOMA) in which the relay selection (RS) scheme is enabled for cooperative networks. In particular, we investigate impact of the number of relays on system performance in term of outage probability. The main factors affecting on cooperative NOMA performance are fixed power allocations coefficients and the number of relay. This paper also indicate performance gap of the outage probabilities among two users the context of NOMA. To exhibit the exactness of derived formula, we match related results between simulation and analytical methods. Numerical results confirms that cooperative NOMA networks benefit from increasing the number of relay.
Volume: 18
Issue: 2
Page: 587-594
Publish at: 2020-04-01

Failed handoffs in collaborative Wi-Fi networks

10.12928/telkomnika.v18i2.14894
Cesar; Universidad Distrital Francisco José de Caldas Hernandez , Diego; Universidad Distrital Francisco Jose de Caldas Giral , C.; Universidad Distrital Francisco Jose de Caldas Salgado
Cognitive radio networks enable a more efficient use of the radioelectric spectrum through dynamic access. Decentralized cognitive radio networks have gained popularity due to their advantages over centralized networks. The purpose of this article is to propose the collaboration between secondary users for cognitive Wi-Fi networks, in the form of two multi-criteria decision-making algorithms known as TOPSIS and VIKOR and assess their performance in terms of the number of failed handoffs. The comparative analysis is established under four different scenarios, according to the service class and the traffic level, within the Wi-Fi frequency band. The results show the performance evaluation obtained through simulations and experimental measurements, where the VIKOR algorithm has a better performance in terms of failed handoffs under different scenarios and collaboration levels.
Volume: 18
Issue: 2
Page: 669-675
Publish at: 2020-04-01

Dynamic multiagent method to avoid duplicated information at intersections in VANETs

10.12928/telkomnika.v18i2.13947
Mohammed I.; Universiti Tun Hussein Onn Malaysia Habelalmateen , A. H.; Universiti Tun Hussein Onn Malaysia Abbas , L.; Universiti Tun Hussein Onn Malaysia Audah , N.; Universiti Tun Hussein Onn Malaysia A. M. Alduais
Vehicular ad hoc networks (VANETs) allow vehicles to contact one another to provide safety and comfort applications. However, mobility is a great challenge in VANETs. High vehicle speed causes topological changes that result in unstable networks. Therefore, most previous studies focused on using clustering techniques in roads to reduce the effect of vehicle mobility and enhance network stability. Vehicles stop moving at intersections, and their mobility does not impact clustering. However, none of previous studies discussed the impact of vehicle stopping at intersections on base stations (BSs). Vehicles that have stopped moving at intersections continue to send the same information to BSs, which causes duplicated information. Hence, this study proposes a new method named dynamic multiagent (DMA) to filter cluster information and prevent duplicated information from being sent to BSs at intersections. The performance of the proposed method was evaluated through simulations during the use of DMA and without-DMA (W-DMA) methods based on real data collected from 10 intersections in Batu Pahat City, Johor, Malaysia. Overall, the proposed DMA method results in a considerable reduction in duplicated information at intersections, with an average percentage of 81% from the W-DMA method.
Volume: 18
Issue: 2
Page: 613-621
Publish at: 2020-04-01

A performance of radio frequency and signal strength of LoRa with BME280 sensor

10.12928/telkomnika.v18i2.14843
Puput; Universitas Merdeka Malang Dani Prasetyo Adi , Akio; Kanazawa University Kitagawa
LoRa is a Radio Frequency module that can send packet data up to 3 km in FSPL.LoRa has 3 different Frequency Radios i.e, 915 MHz, 868 MHz, and 433 MHz. LoRa testing is based on different distances, BME280 provides Barometric Pressure, Temperature, and Humidity data. An analysis from the results of the Received Signal Strength to the distance (m) to the farthest point to prove and provide QoS data from LoRa 915 MHz. Sensor nodes are built using ADR and Automatic sleep mode algorithms. Communication systems between nodes are built dynamic sensor nodes in mesh networking. Monitoring signal transferring on the 915 MHz Frequency waveform is carried out using the Textronix Spectrum analyzer. Based on the BME280 Data packet transmission from the LoRa 915 MHz Transmitter to the Receiver Receiver at a distance of 100m is -84 dBm and at a distance of 500m is -107 dBm. The LoRa Internet Gateway has 2 types of settings, i.e, application, and gateway, this setting is to find out the location of the gateway with longitude and latitude. Furthermore, the gateway holds Sensor data from the End node, while the Application Server displays sensor data in the form of Graphics in realtime.
Volume: 18
Issue: 2
Page: 649-660
Publish at: 2020-04-01

A compact UWB monopole antenna with penta band notched characteristics

10.12928/telkomnika.v18i2.14542
Majed O.; Al-Balqa Applied University Al-Dwairi , Amjad Y.; Al-Balqa Applied University Hindi , Mohamed S.; Taif University Soliman , Mohammad F.; Al-Balqa Applied University Aljafari
A modified rectangular monopole ultra-wideband (UWB) antenna with penta notched frequency bands is presented. An inverted U shaped and slanted U-shaped on the radiating patch are inserted to achieve WiMAX and ARN bands rejection respectively, two mirrored summation Σ-shaped and four mirrored 5-shaped slots are inserted on the partial ground to achieve WLAN and X-band bands rejection respectively, finally rectangular shaped slot with partially open on the feed is inserted to achieve ITU-8 band rejection. The proposed antenna which was simulated has a compact size 30×35×1.6 m3. It is operated with impedance bandwidth 2.8-10.6 GHz at |S11| < −10 dB, that supported UWB bandwidth with filtering the five narrowbands that avoid the possible interference with them. The simulated resonant frequency for notched filters received 3.55, 4.55, 5.53, 7.45, 8.16 GHZ, for WiMAX, ARN, WLAN, X-Band, ITU-8 respectively. The proposed antenna is suitable for wireless communication such as mobile communication and internet of everything (IoE). Throughout this paper, CST-EM software package was used for the design implementation. Surface current distributions for all notched filters were investigated and shown that it is concentrated around the feeding point and the inserted notched slots proving that there is no radiation to the space due to maximum stored electromagnetic energy around each investigated notch slot, proving that the slots play a role of a quarter wavelength transformer which generates for each notched band, maximum gain, and radiation pattern are also investigated.
Volume: 18
Issue: 2
Page: 622-630
Publish at: 2020-04-01

The development of a wireless LCP-based intracranial pressure sensor for traumatic brain injury patients

10.11591/ijece.v10i2.pp1229-1238
Preedipat Sattayasoonthorn , Jackrit Suthakorn , Sorayouth Chamnanvej M.D
Raised intracranial pressure (ICP) in traumatic brain injury (TBI) patients can lead to death. ICP measurement is required to monitor the condition of a patient and to inform TBI treatment. This work presents a new wireless liquid crystal polymer (LCP) based ICP sensor. The sensor is designed with the purpose of measuring ICP and wirelessly transmitting the signal to an external monitoring unit. The sensor is minimally invasive and biocompatible due to the mechanical design and the use of LCP. A prototype sensor and associated wireless module are fabricated and tested to demonstrate the functionality and performance of the wireless LCP-based ICP sensor. Experimental results show that the wireless LCP-based ICP sensor can operate in the pressure range of 0 - 60.12 mmHg. Based on repeated measurements, the sensitivity of the sensor is found to be 25.62 µVmmHg-1, with a standard deviation of ± 1.16 µVmmHg-1. This work represents a significant step towards achieving a wireless, implantable, minimally invasive ICP monitoring strategy for TBI patients.
Volume: 10
Issue: 2
Page: 1229-1238
Publish at: 2020-04-01

Genomic repeats detection using Boyer-Moore algorithm on Apache Spark Streaming

10.12928/telkomnika.v18i2.14883
Lala Septem; Universitas Pendidikan Indonesia Riza , Farhan Dhiyaa; Universitas Pendidikan Indonesia Pratama , Erna; Universitas Pendidikan Indonesia Piantari , Mahmoud; Djillali Liabes University Fahsi
Genomic repeats, i.e., pattern searching in the string processing process to find repeated base pairs in the order of Deoxyribonucleic Acid (DNA), requires a long processing time. This research builds a big-data computational model to look for patterns in strings by modifying and implementing the Boyer-Moore algorithm on Apache Spark Streaming for human DNA sequences from the Ensemble site. Moreover, we perform some experiments on cloud computing by varying different specifications of computer clusters with involving datasets of human DNA sequences. The results obtained show that the proposed computational model on Apache Spark Streaming is faster than standalone computing and parallel computing with multicore. Therefore, it can be stated that the main contribution in this research, which is to develop a computational model for reducing the computational costs, has been achieved.
Volume: 18
Issue: 2
Page: 783-791
Publish at: 2020-04-01

Water bath sonicator integrated with PID-based temperature controller for flavonoid extraction

10.12928/telkomnika.v18i2.14830
Zainul; Universitas Brawijaya Abidin , M. Aziz; Universitas Brawijaya Muslim , Muhammad; Universitas Brawijaya Muqorrobin , Warsito; Universitas Brawijaya Warsito
In this research, water bath sonicator was fabricated to extract bioactive compound of plants material using sound energy (ultrasonic waves) and heater. The bioactive compound, flavonoid, has high sensitivity to temperature and extraction time and previous research stated best treatment with combination of 45˚C and 20 minutes. Therefore, fabricated water bath sonicator was equipped with proportional integral derivative (PID) based temperature controller and timer. Based on a calculation using the Ziegler-Nichols tuning method, Kp, Ki, Kd parameters are 16.59, 0.0279, and 2463.6, respectively. The experimental result shows that the PID controller can perform as design specification with overshoot 1.39%, error steady-state 0.688% and settling time 37.2 minutes. Furthermore, it was proven that the PID controller has contribution to extract more flavonoid.
Volume: 18
Issue: 2
Page: 970-976
Publish at: 2020-04-01

Retina blood vessel extraction based on kirsch’s template method

10.11591/ijeecs.v18.i1.pp318-325
Nur Syazlin Zolkifli , Ain Nazari , Mohd Marzuki Mustafa , Wan NurShazwani Wan Zakaria , Nor Surayahani Suriani , Wan Nur Hafsha Wan Kairuddin
Analysis on the retina blood vessels from fundus images have been widely used in the medical community to detect the disorder condition in the blood vessels. An automated tracing of retina blood vessel can help to provide valuable computer-assisted diagnosis for the ophthalmic disorders. Thus, it helps to reduce the time for the ophthalmologist to analyses and diagnose the result of the fundus image of patient. The purpose of this research is to build an algorithm to trace the retina blood vessels. The method to be used in this research consist of two parts which are the pre-processing part and the feature extraction by using the Kirsch’s template. Combining the pre-processing at the early stage and feature extraction at the next stage is applied to extract the edges of the blood vessels.  The proposed algorithm was verified by using two online databases, DRIVE and HRF to validate the performance measures. Hence, proposed method is capable to extract the retina blood vessel and give the accuracy of 0.7917, the sensitivity of 0.9077 and the specificity of 0.7215. In conclusion, the extraction of the blood vessels is highly recommended as the early screening stage for the eye diseases beneficially.
Volume: 18
Issue: 1
Page: 318-325
Publish at: 2020-04-01

Fisher-Yates and fuzzy Sugeno in game for children with special needs

10.12928/telkomnika.v18i2.14906
Diena Rauda; UIN Sunan Gunung Djati Bandung Ramdania , Mohamad; UIN Sunan Gunung Djati Bandung Irfan , Salma Nuralisa; UIN Sunan Gunung Djati Bandung Habsah , Cepy; UIN Sunan Gunung Djati Bandung Slamet , Wisnu; UIN Sunan Gunung Djati Bandung Uriawan , Khaerul; Universitas Sangga Buana Manaf
As a country that has its language, English is an international language that needs to be mastered. Until now, the mastery of English in Indonesian on an international scale is in a low category. Learning English should be taught to children from an early age. For children with special needs, special learning methods are needed so that the material is conveyed. Educational games can be used as an interesting learning media. In this study, an English educational game was created that had the concepts of a quiz, rearrange, and matching. Fisher-Yates algorithm was applied to randomize the questions so that the questions that came out varied. Fuzzy Sugeno algorithm is also applied to the scoring calculation, with input variables of time, value, and the number of stars obtained. The system test outcomes show that the application of the Fisher-Yates algorithm was successful because every question that came out was randomized. The application of the Fuzzy Sugeno algorithm happened also successful because of the high degree of accuracy. Besides, the use of games shows there is an increase in student understanding as evidenced by the acquisition of grades. The results of the average value in doing the test is from 80.41 to 88.3 after playing the game. 
Volume: 18
Issue: 2
Page: 879-889
Publish at: 2020-04-01

CMOS based thermal detector for processor

10.11591/ijeecs.v18.i1.pp276-283
Lee Che Yang , Warsuzarina Mat Jubadi
This project proposed a design of low power CMOS-based thermal detector which can detect the temperature of processor such as in Central Processing Unit. By re-designing temperature detector circuit using CMOS technology, the reduction in power consumption and area size of the thermal detector can be obtained.  In this paper, the design of thermal detector consists of temperature sensing core, amplifier, and Analog to Digital Converter (ADC), respectively. The sensor was designed using 0.13 µm CMOS technology and operates by sensing the temperature of processor and produced a digital output value. The temperature detection range was setup between 0 °C to 80 °C with 10 °C resolution. The temperature detector was capable to show temperature readings in binary value. It consumed an average power of 558.2 µW and a space occupancy of 0.0118 mm².
Volume: 18
Issue: 1
Page: 276-283
Publish at: 2020-04-01
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