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29,905 Article Results

Design of a CMOS-based microwave active channelized bandpass filter

10.12928/telkomnika.v17i6.11662
Jarjar; Faculty of Sciences and Technology (FST)-Signals, Systems and Components laboratory (LSSC) Mariem , Pr. El Ouazzani; Faculty of Sciences and Technology (FST)-Signals, Systems and Components laboratory (LSSC) Nabih
A two-branch microwave active bandpass filter is designed through the channelized filtering technique as well as the transversal concept. Both the main and the auxiliary branches, connected without power dividers/combiners, rely on C-coupled active third order Chebyshev bandpass filters. A lumped element signal delay circuit is also introduced in the main channel. Active inductors based on the gyrator-C topology, are involved in the Chebyshev filters’ structure. CMOS-based Operational Transconductor Amplifier (OTA) circuits are the building blocks of these inductors. The proposed active transversal channelized filter produces an elliptic narrow band response, centered at 1.13 GHz. Simulation results, obtained by means of the PSPICE code according to the 0.18 ΞΌm TSMC MOS technology, indicate excellent performances illustrating good impedance matching, low insertion losses and high selectivity. Finally, the noise analysis shows that the filter has a low noise figure in the bandwidth.
Volume: 17
Issue: 6
Page: 2851-2859
Publish at: 2019-12-01

A novel model for solar radiation prediction

10.12928/telkomnika.v17i6.12729
Ibrahim S.; Kano University of Science and Technology Madugu , B. J.; University of Ilorin Olufeagba , Yinusa A.; University of Ilorin Adediran , F.; Kano University of Science and Technology Abdulkadir , A.; Ahmadu Bello University Zaria Abdulkarim , James U.; University of Ilorin Inaku , A. U.; Hussiani Adamu Federal Polytechnic Lawan
Energy for fulfilling basic community/individual needs has come to constitute the first article of expectation in all contemporary societies. The exploitation of renewables notably solar in electricity generation has brought relief to the fulfilment of energy demand especially among susceptible communities. In this paper yearly minimum solar radiation of Kano (12.05Β°N; 08.2Β°E; altitude 472.5 m; 3 air density 1.1705 kg/m3) for 46 years is used to generate a prediction model that fits the data using autoregressive moving average (ARMA) and a new model termed autoregressive moving average process (ARMAP). Comparison between the ARMA and ARMAP models showed a tremendous improve in the sum of square error reduction between the actual data and the forecasted data by 47%.
Volume: 17
Issue: 6
Page: 3100-3109
Publish at: 2019-12-01

Modeling of three-limb three-phase transformer relates to shunt core using in industrial microwave generators with n=2 magnetron per phase

10.11591/ijece.v9i6.pp4556-4565
H. Outzguinrimt , M. Chraygane , M. Lahame , R. Oumghar , R. Batit , M. Ferfra
This paper describes the development and implementation of a digital simulation model of a three-phase transformer relates to shunt core transformer, which used to drive magnetron tubes in the microwave. The focus of this study is based on modeling of a new shell-type of three limbs three-phase transformer. The model uses to feed two magnetrons instead of one magnetron per phase. The proposed model is established on the simultaneous analysis of a duo electromagnetic lumped component equivalent circuit. This latter was implemented in a MATLAB environment under rated conditions. The results obtained from the application of the analytical method are provided results in conformity to the experimental tests in the case of single phase high voltage power supply for one magnetron.
Volume: 9
Issue: 6
Page: 4556-4565
Publish at: 2019-12-01

A review of cloud oriented mobile learning platform and frameworks

10.11591/ijece.v9i6.pp5529-5536
Ahmad Shukri Bin Moh Noor , Marwan Nasser Yousef Atoom , Rabiei Mamat
With the continued growth of mobile devices usage, wireless communications improvement, and cloud computing evolution, many educational institutions around the world, especially universities and colleges, began to provide their students with mobile learning systems based on cloud computing. The widespread, ubiquitous, and flexible natures of mobile devices make mobile learning an attractive alternative in education, particularly when integrating it with cloud computing which is the up-to-date technology that delivers computing hardware and software as services. However, the participatory between mobile learning and cloud computing as a cloud based mobile learning (CBML) becomes one of the important methods in the learning process. Many researches have attempted to combine the unique features of CBML in a form of frameworks. These frameworks have been designed to identify, categorize, or evaluate the major components of the CBML system. This paper is an attempt to identify the important role of cloud computing technology in mobile learning, investigate the main advantages and limitations of CBML systems, and explore the previously designed CBML frameworks.
Volume: 9
Issue: 6
Page: 5529-5536
Publish at: 2019-12-01

Conceptual model for the integration of personal attribute skills in electrical technology education curriculum

10.11591/ijere.v8i4.20301
Dahiru Sale Mohammed , Sarimah Ismail
The current curriculum of Electrical Technology Education (ETE) of Nigerian Universities has been criticized for not meeting the desired challenges. The personal attribute skills were found are not integrated in the curriculum. Hence, a study was conducted to determine the types of personal attribute skills, their respective indicators and to develop a conceptual model for the integration of personal attribute skills for ETE curriculum. Mixed methods exploratory research design was employed for the study. 10 industry technical managers were interviewed and the interview data were analyzed using coding process of open coding, axial coding and selective coding. The interview data were used to develop a structured questionnaire that validated by 4 experts. Alpha value for pilot test was 0.89. Sample of the survey were 646 including 528 ETE graduates, 22 ETE lecturers and 96 industry technical managers. Stepwise Linear Regression and Confirmatory Factor Analysis were used to analyze the survey. The study developed a conceptual model for the integration of personal attribute skills that consists of two major skills: attitude skills and trait skills. This study recommended the implementation of the conceptual model for the integration of employability skills in ETE curriculum.
Volume: 8
Issue: 4
Page: 705-712
Publish at: 2019-12-01

A fuzzy micro-climate controller for small indoor aeroponics systems

10.12928/telkomnika.v17i6.12214
Bambang Dwi; Universitas Brawijaya Argo , Yusuf; Universitas Brawijaya Hendrawan , Ubaidillah; Universitas Brawijaya Ubaidillah
The Indonesian agricultural sector faces challenges producing affordably priced food using sustainable practices. A soilless cultural practice, such as indoor aeroponics, is a compelling alternative to conventional agriculture. The objective of the present study was to develop a system for micro-climate management in a pilot-scale indoor aeroponics system. For this purpose, three fuzzy logic controllers were developed and evaluated to maintain plant chamber parameters (temperature, relative humidity, and light intensity) at desired set points controlled by embedded system controls designed using BASCOM-AVR software. The results showed that the fuzzy controllers provided excellent responses and experienced relatively low errors in all controlled parameters. All parameters changes followed the set point very smoothly and responded accordingly.The averaged percent of working times in which temperature, relative humidity, and light intensity were maintained within less than Β±1Β°C, Β±5%, and Β±30 lux from the set points were found to be 88.43%, 95.91%, and 85.51%, respectively.
Volume: 17
Issue: 6
Page: 3019-3026
Publish at: 2019-12-01

Study the effect of thin film thickness on the optical features of (IR5 laser dye/CdSe nanoparticles) samples

10.12928/telkomnika.v17i6.13004
Mithaq M.; Kufa University Mehdy Al-Sultani
The linear optical features such as (transmittance T, absorbance A, the effective length 𝐿𝑒𝑓𝑓, absorption coefficient 𝛼 and refractive index 𝑛 ) for the thin films samples of (3x10-3 mol/l of (IR5) laser dye, 0.02 gm of (CdS) nanoparticles and 0.04 gm of pp polymer) had been studied at different values of film thickness in one time and at different number of Yb:GdVO4 laser pulses. The non-linear optical features in terms of transmittance difference Ξ”π‘‡π‘βˆ’π‘£, non-linear refractive index 𝑛2, non–linear phase shift Ξ”π›·π‘œ non-linear absorption coefficient 𝛽 and minimum normalized transmittance 𝑇(𝑍) have been computed in relation to obtained normalized transmittance data from setup of Z-scan with open and closed apertures, calculated for (3x10-3 mol/l of (IR5) laser dye, 0.02 gm of (CdSe) nanoparticles and 0.04 gm of (pp) polymer) thin films at different values of film thickness at in one time and at different Yb:GdVO4 laser pulses. Thick films causes in deleting the non-linear effects generated by different layers. The (CdSe) nanoparticles leads to an absorption shifting of the wavelengths to lengthier wavelengths of red shift. So, this can be used in selecting the nanoparticles and medium with applicable exciting wavelengths. The film thickness and the laser pulses have the main effects in consolidating the Non-linear optical features.
Volume: 17
Issue: 6
Page: 2877-2884
Publish at: 2019-12-01

Streaming in-patient BPM data to the cloud with a real-time monitoring system

10.12928/telkomnika.v17i6.13263
Mohammed G.; Northern Technical University Ayoub , Mazin N.; Northern Technical University Farhan , Mohamme S.; Northern Technical University Jarjees
Monitoring the heart activities for old people or people with medical history (Arrhythmia or CHD) is targeted by most new medical technologies. This paper demonstrated an in-patient real-time monitoring system for heart rate estimation. A ratio of beats per minute (BPM) is continuously recorded, streamed and archived to the cloud via WeMos WiFi development board. This cost effective system is simply based on two sub-systems: BPM data acquisition through pulse sensor and WeMos-based communication systems. The streamed BPM data are saved instantaneously in Google drive as spreadsheets which can only be accessed by authorized persons wherever the internet service is available. Thus, the person in charge can remotely observe the patient’s status and do analytics for the archived data. A pilot study with eight subjects was carried out to validate the developed BPM tele-monitoring system. Encouraging results have been achieved.
Volume: 17
Issue: 6
Page: 3120-3125
Publish at: 2019-12-01

Parallelism in web services: design of parallel XML parser for web services

10.11591/ijeecs.v16.i3.pp1407-1415
Rohitkumar Rudrappa Wagdarikar , Sandhya P
A WS provides the communication between heterogeneous systems. While performing this operation, we need to focus on QoS of consumer, provider and registry directory. There will be some parameters like WS selection, prediction and rank these are parameters need to consider while QoS implementation in web services. While performing integration in web services we need to focus on QoS requirements regarding server and network performance. Performance of WS is related to locations i.e the network distance and the Internet connections between consumer and provider. There will be more QoS approach which works on consumers collected QoS data, based on this data system can predict the QoS of WS. Throughput and response time are the QoS of WS. In this paper, we have proposed parallel XML parser, by which we can parse UDDI, WSDL and SOAP XML files parallel by which it will improve the response time and throughput of WS.
Volume: 16
Issue: 3
Page: 1407-1415
Publish at: 2019-12-01

A review on software defined network security risks and challenges

10.12928/telkomnika.v17i6.13119
Tsehay Admassu; Aksum University Assegie , Pramod Sekharan; Aksum University Nair
Software defined network is an emerging networking architecture that separates the traditional integrated control logic and data forwarding functionality into different planes, namely the control plane and data forwarding plane. The data plane does and end to end data delivery. And the control plane does the actual network traffic forwarding and routing between different network segments. In software defined network the networking infrastructure layer where the entire networking device, such as switches and routers reside is connected with the separate controller layer with the help of standard called OpenFlow protocol. It is a standard protocol that allows different vendor devices like juniper switches, cisco switches and huawei switches to be connected to the controller. The centralization of the SDN controller made the network more flexible, manageable and dynamic, such as provisioning of bandwidth, dynamic scale out and scale in compared to the traditional communication network, however the centralized SDN controller is more vulnerable to security risk factors such as DDOS and flow rule poisoning attack. In this paper we will explore the architectures and principles of software defined network and security risks with the centralized SDN controller and possible ways to mitigate these risks.
Volume: 17
Issue: 6
Page: 3168-3174
Publish at: 2019-12-01

Performance analysis of high-k materials as stern layer in ion-sensitive field effect transistor using commercial TCAD

10.12928/telkomnika.v17i6.12852
Ahmed M.; Universiti Teknikal Malaysia Melaka (UTeM) Dinar , AS Mohd; Universiti Teknikal Malaysia Melaka (UTeM) Zain , F.; Universiti Teknikal Malaysia Melaka (UTeM) Salehuddin , Mowafak K.; Universiti Teknikal Malaysia Melaka (UTeM) Mohsen , Mothana L.; Universiti Teknikal Malaysia Melaka (UTeM) Attiah , M. K.; Universiti Teknikal Malaysia Melaka (UTeM) Abdulhameed
High-k materials as a STERN Layer for Ion-Sensitive-Field-Effect-Transistor (ISFET) have improved ISFET sensitivity and stability. These materials decrease leakage current and increase capacitance of the ISFET gate toward highest current sensitivity. So far, many high-k materials have been utilized for ISFET, yet they were examined individually, or using numerical solutions rather than using integrated TCAD environment. Exploiting TCAD environment leads to extract ISFET equivalent circuit parameters and performs full analysis for both device and circuit. In this study we introduce a comprehensive investigation of different high-k material, Tio2, Ta2O5, ZrO2, Al2O3, HfO2 and Si3N4 as well as normal silicon dioxide and their effects on ISFET sensitivity and stability. This was implemented by developing commercial Silvaco TCAD rather than expensive real fabrication. The results confirm that employing high-k materials in ISFET outperform normal silicon dioxide in terms of sensitivity and stability. Further analysis revealed that Titanium dioxide showed the highest sensitivity followed by two groups HfO2, Ta2O5 and ZrO2, Al2O3 respectively. Another notable exception of Si3N4 that is less than other materials, but still have higher sensitivity than normal silicon dioxide. We believe that this study opens new directions for further analysis and optimization prior to the real cost-ineffective fabrication.
Volume: 17
Issue: 6
Page: 2867-2876
Publish at: 2019-12-01

Clarification of the optimum silica nanofiller amount for electrical treeing resistance

10.12928/telkomnika.v17i6.10605
Z.; Sriwijaya University Nawawi , M. A. B.; Sriwijaya University Sidik , M. I.; Sriwijaya University Jambak , C. L. G.; Universiti Teknologi Malaysia Pavan Kumar , Aulia; Andalas University Aulia , M. H.; Universiti Teknologi Malaysia Ahmad , A. A.; Universiti Sains Malaysia Abd Jamil
This paper aims to clarify the optimum amount of fumed silica (SiO2) nanofiller in resisting the initiation and propagation of electrical treeing in silicone rubber (SiR). Unlike other works, SiR/SiO2 nanocomposites containing seven different weight percentages of SiO2 nanofiller were prepared for this purpose. To achieve the objective, the electrical tree characteristics of the SiR/SiO2 nanocomposites were investigated by comparing the tree initiation voltage, tree breakdown time, tree propagation length and tree growth rate with its equivalent unfilled SiR. Moreover, the structural and morphological analyses were conducted on the SiR/SiO2 nanocomposite samples. The results showed that the SiR, when added with an appropriate amount of SiO2 nanofiller, could result in an improved electrical tree resistance. It implies that the 5 wt% of silica is the optimum amount to achieve the optimal electrical tree resistance such that above 5 wt%, the tree resistance performance has been abruptly reduced, subjected to the agglomeration issue.
Volume: 17
Issue: 6
Page: 2903-2911
Publish at: 2019-12-01

A design of radial line slot array antennas using the specification of panel antennas

10.12928/telkomnika.v17i6.12679
Teddy; Universitas Islam Negeri Sultan Syarif Kasim Purnamirza , Muhammad; UIN Sultan Syarif Kasim Riau Ralibi , Imran M. Bin; Universiti Teknikal Malaysia Malaka Ibrahim , Rika; UIN Sultan Syarif Kasim Riau Susanti , Halim; UIN Sultan Syarif Kasim Mudia , Depriwana; UIN Sultan Syarif Kasim Riau Rahmi , Sutoyo; UIN Sultan Syarif Kasim Riau Sutoyo , Mulyono; UIN Sultan Syarif Kasim Riau Mulyono
RLSA antennas were suggested by several researches as Wi-Fi antennas in addition to panel antennas. Therefore, this paper researched the possibility of this suggestion. We used the size of an available in market 16 dBi panel antenna (225 mm2) as the size for our developed RLSA antenna. Based on this size, we developed 60 RLSA models using extreme beamsquint technique and simulated them. We then chose a best model with a best performance. The best model was then fabricated and measured. The simulation and measurement results show that the developed RLSA antenna has better performance compared to the 16 dBi panel antenna in term of gain (0.25 dB higher) and bandwidth (570 MHz wider). The RLSA antenna also tested as antenna for a Wi-Fi device and it showed good performance.
Volume: 17
Issue: 6
Page: 3066-3072
Publish at: 2019-12-01

Modelling of scanning pulsed eddy current testing of normal and slanted surface cracks

10.11591/ijeecs.v16.i3.pp1297-1302
Faris Nafiah , Ali Sophian , Md Raisuddin Khan , Ilham Mukriz Zainal Abidin
Thanks to its wide bandwidth, pulsed eddy current (PEC) has attracted researchers of various backgrounds in the attempt to exploit its benefits in Non-destructive Testing (NDT). The ability of modelling PEC problems would be a precious tool in this attempt as it would help improve the understanding of the interaction between the transient magnetic field and the specimen, among others. In this work, a Finite Element Modelling (FEM) has been developed and experimental test data have been gathered for its validation. The investigated cases were simulated surface cracks of different sizes and angles. The study involved looking at time-domain PEC signals at different spatial distances from the cracks’ faces, which would particularly be useful for modelling scanning PEC probes. The obtained results show a good agreement between the FEM and experiment, demonstrating that the modelling technique can be used with confidence for solving similar problems.
Volume: 16
Issue: 3
Page: 1297-1302
Publish at: 2019-12-01

Characterization of silicon nanowire transistor

10.12928/telkomnika.v17i6.13084
Hani Taha; Universiti Malaysia Pahang Al Ariqi , Waheb A.; Universiti Malaysia Pahang Jabbar , Yasir; Ishik University Hashim , Hadi Bin; Universiti Malaysia Pahang Manap
This paper analyses the temperature sensitivity of Silicon Nanowire Transistor (SiNWT) depends on the diameter (D.ch) of channel. In addition, it also investigates the possibility of utilizing SiNWT as a Nano- temperature sensor. The MuGFET simulation tool has been utilized to conduct a comprehensive simulation to evaluate both electrical and temperature characteristics of SiNWT. Current-voltage characteristics with different values of temperature and with a varying diameter of the Nano wire channel (D.ch = 80, 40, 20 and 10 nm), were simulated. Diode operating mode connection of the transistor is suggested for measuring the temperature sensitivity of SiNWT. As simulation results demonstrated, the best temperature sensitivity was occurred at lower temperature with increasing the channel diameter. We also illustrate the impact of varying temperature and channel diameter on electrical characteristics of SiNWT including, Subthreshold Swing (SS), Threshold voltage (V.th), and Drain-induced barrier lowering (DIBL), which were proportionally increased with the operating temperature.
Volume: 17
Issue: 6
Page: 2860-2866
Publish at: 2019-12-01
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