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31,456 Article Results

Identifying of emotional quotient junior high school students in mathematics

10.11591/ijere.v10i1.20681
Syaiful Syaiful , Kamid Kamid , Nizlel Huda
This study aimed to determine the emotional intelligence of junior high school students, especially in managing emotions, recognizing emotions, and motivating themselves. This was quantitative study with survey design. There were 102 respondents participated in this research that were obtained based on purposive technique. The instruments used in this study were questionnaires and semi-structured interviews and data analysis using descriptive statistics, including mean, min, max, categorization, and percentage. From the results of the investigation that has been done, it is found that there is emotional intelligence of students in mathematics which is shown by the aspect of recognizing emotions which has a suitable category of 61.8% (63 of 102) students, the issue of managing emotions has an appropriate category of 53.9% (56 out of 102) students. The self-motivation aspect has a suitable category of 60.8% (62 out of 102) students. Students need to be allowed to develop direct experiences and thoughts on learning activities.
Volume: 10
Issue: 1
Page: 202-208
Publish at: 2021-03-01

Supplier side optimal bidding strategy for electricity market using bacterial foraging optimization algorithm

10.11591/ijape.v10.i1.pp58-67
Uday Sriram L , Siva Nagaraju S , Chandram Karri
In this article, bacterial foraging optimization (BFO) algorithm is developed for single side optimal bidding strategy in an electricity market. Optimal bidding strategy is one of the important functions in the electricity market along with forecasting of the electricity price and the profit based unit commitment. The prime objective of generating company (Genco) is to maximize their profit when they participate in the bidding pro-cess. The BFO algorithm has been used to maximize the probability density function (pdf). In the second stage the BFO algorithm is again applied to maximize the profit of the suppliers. The proposed algorithm is developed in MATLAB (Version, 2019) and tested on standard test case available in the literature. Also, the simulation results are presented and compared. It is noticed that the proposed method yields the best results in terms of profit.
Volume: 10
Issue: 1
Page: 58-67
Publish at: 2021-03-01

State of charge estimation by using extended Kalman filter based on improved open circuit voltage model

10.11591/ijape.v10.i1.pp1-10
Maamar Souaihia , Bachir Belmadani , Rachid Taleb , Kamel Tounsi
This paper focuses on the state of charge estimation (SOC) for battery Li-ion. By modeling a battery based on the equivalent circuit model, the extended Kalman filter approach can be applied to estimate the battery SOC. An electrical battery model is developed in Matlab, Where the structure of the model is detailed by equations and blocks. The battery model has been validated from the experiment results. The comparison shows a good agreement in predicting the voltage, SOC estimation and the model performs better in SOC estimation.
Volume: 10
Issue: 1
Page: 1-10
Publish at: 2021-03-01

Implementation effects of economics and market operations based model for traditionally integrated power systems

10.11591/ijeecs.v21.i3.pp1247-1255
Youssef Mobarak , Nithiyananthan Kannan , Fahd Alharbi , Faisal Albatati
The main objective of this paper is to introduce power system economic operations in traditionally integrated power systems and market operations in deregulated power systems and study its effects. The power system economic operation is mathematically treated as an optimization problem. Also, a function of economic operation is to minimize generation cost, transmission losses, and so on, subject to power system operation constraints. In this paper, we start from generation cost formulations and introduce traditional economic dispatch model, optimal power flow model, and unit commitment model. With the deregulation of the power industry, integrated power system is unbundled to generation, transmission, and distribution. Electricity is traded in the wholesale market. Small customers purchase energy from electricity retailers through the retail market. The electricity market is operated for energy trading while satisfying power system operation requirements. Electricity market is mathematically modelled as an optimization problem that is subject to power system operation constraints and market operation constraints.
Volume: 21
Issue: 3
Page: 1247-1255
Publish at: 2021-03-01

A low-cost IoT-based auscultation training device

10.11591/ijeecs.v21.i3.pp1356-1363
Heri Andrianto Andrianto , Daniel Perdana Sutanto , Yunus Adhy Prasetyo
Auscultation training devices are needed by teachers and students in health schools to practice auscultation techniques. In this paper, a low-cost IoT-based auscultation training device has been developed using NodeMCU, four proximity sensors, metal as a stethoscope, a switch, an android smartphone, an earphone, and a phantom doll. The message queuing telemetry transport (MQTT) protocol has been used for data communication between NodeMCU and smartphones, therefore an auscultation training hardware can be used by many students who have auscultation training application on their smartphones that subscribe to topics. The results showed that an auscultation training device was able to detect a stethoscope. Auscultation training application on a smartphone successfully plays normal and abnormal breathing sounds based on subscribed topics. With a production cost of less than 15 USD, we offer an inexpensive IoT-based auscultation training device. 
Volume: 21
Issue: 3
Page: 1356-1363
Publish at: 2021-03-01

Analysis of teacher performance to build student interest and motivation towards mathematics achievement

10.11591/ijere.v10i1.20711
Hardi Tambunan , Bornok Sinaga , Wahyu Widada
The purpose of this study was to determine the impact and categories of teacher performance in building student interest and motivation on mathematics achievement. The population in this study was students in the eighth grade of junior high schools from six public and two private schools, and a sample of 277 students was taken by cluster sampling. Data collection instruments used a questionnaire, and data analysis was done by using by descriptive and path analysis. The results of data analysis showed that partially, teacher performance significantly affected student interest and motivation excel at mathematics. Simultaneously, teacher performance is very significant in influencing student interest and motivation to be excellent in mathematics. Partially, teacher performance builds interest and student motivation for mathematics achievement is low category. Simultaneously, teacher performance builds student interest and motivation to excel at mathematics is low category. Both of these can be caused by the ability of teachers to build motivation and interest is not good, so students are also less interested and motivated to learn mathematics.
Volume: 10
Issue: 1
Page: 42-47
Publish at: 2021-03-01

Performance analysis of power generation by wood and woody biomass gasification in a downdraft gasifier

10.11591/ijape.v10.i1.pp80-88
Sahar Safarian , Runar Unnthorsson , Christiaan Richter
An equilibrium simulation model was developed by applying Aspen Plus to evaluate the performance of 28 wood and woody biomass (W&WB) gasification in a downdraft gasifier integrated with power production unit. The developed simulation model does not focus the gasification process as a closed box, it considers important processes in gasification like drying, pyrolysis, combustion, gasification and integrated with power production plant (combustion chamber plus gas turbine). The results for the 28 W&WB alternatives show that the net power produced from 1-ton feedstock entering to the gasification system is between the interval [0-400 kW/ton] and among them, gasification system derived from Tamarack bark biomass significantly outranks all other systems by producing 363 kW/ton, owing to the favorable results obtained in the performance analysis. Moreover, effect of various operating parameters such as gasification temperature and air to fuel ratio (AFR) on the system performance was carried out. Finally, the developed model is applied as an effective tool to assess the impact of so many biomasses and operating parameters on output power.
Volume: 10
Issue: 1
Page: 80-88
Publish at: 2021-03-01

Investigation of 22 kV silane cure TR-EPR cable

10.11591/ijape.v10.i1.pp41-47
Fernando Agustin , Akhtar Kalam , Aladin Zayegh
EPR-insulated cables for distribution power network are not commonly used in Australia. This is due to the higher DDF of common EPR cables when compared with XLPE that contributes to the power loss and economics in transmitting electricity. This led to the development of EPR called TR-EPR with significantly lower DDF and uses silane curing process to address concerns about cost-effectiveness. The thermal behavior of low DDF silane cure TR-EPR is investigated for 30 months of exposure to the maximum operating temperature of material. The physical changes in the samples throughout the long-term aging are examined to create an opportunity to model the expected life cycle of TR-EPR cable under thermal stress. The cross-linking characteristics of TR-EPR cable are also examined by ambient curing that simulates the storage condition for unused cable and by cable heating process that simulates the condition when the cable is energized. The results are tabulated for a better understanding of the time for the material to cross-link at various conditions. The improved partial discharge values after cross-linking are also presented.
Volume: 10
Issue: 1
Page: 41-47
Publish at: 2021-03-01

Smart power grid vulnerability analysis in composite system through power grid modelling

10.11591/ijape.v10.i1.pp11-20
Shouvik kumar Samanta , Chandan kumar Chanda
A though the number of traditional literature reviews most of the researchers in this area have concluded that modern intelligent electric network a referred standard new model which is considering for proposed power flow model analysis of smart power grid vulnerability through composite network. By the theorem of max-flow and complex power network theorems that are represented the advance vulnerability indices for pick out endangered lines of the smart grid network. In other hand, the power flow model and existing models simulation are examined on the IEEE 39-bus test model. The results of the simulation introduced that the proposed concept of grid model, estimation and the index application are more adequate in smart grid weakness power and efficiency analysis. In this paper briefly summarize the methods and probabilities of a vulnerability index which was explained in specific in references. Therefore, it is imperative to further implement new models and new tools so as to reach the novel state and moderate the huge or massive potential shutoff
Volume: 10
Issue: 1
Page: 11-20
Publish at: 2021-03-01

Single switch Z-source/quasi Z-source DC-DC converters

10.11591/ijape.v10.i1.pp68-79
V Saravanan , M Sabitha , V Bindu , Venkatachalam K M , M. Arumugam
This paper analyzes a family of high step up single switch switched capacitor boost converters and Z-source/quasi Z-source dc-dc converters to provide high output dc voltage gain with single stage conversion having low voltage stress on active switches, capacitors, and diodes. The operating principles, parameters design guideline of these converters are presented along with simulation results. The discussed topologies in this paper are aimed to increase the conversion system reliability and efficiency with decreased cost, volume, and weight. These power converter topologies are used for various applications such as photovoltaic (PV) systems, wind energy conversion, fuel cells, uninterruptible power systems, motor drives, energy storage systems, electric vehicle and power factor correction. Simulations are carried out in MATLAB/Simulink environment.
Volume: 10
Issue: 1
Page: 68-79
Publish at: 2021-03-01

Grid integration of PMSG based wind energy conversion with battery storage system

10.11591/ijape.v10.i1.pp48-57
Venkatachalam K M, , V. Saravanan
In this paper, the design and implementation of a permanent magnet synchronous generator (PMSG) based wind energy conversion system and battery bank storages are connected to utility grid. It has phase locked loop (PLL) control strategy as it provides for control single-phase grid connected inverter with constant dc-link voltage. The dc-link is interfaced to a permanent magnet synchronous generator through diode bridge rectifier (DBR) with dc-dc boost converter, battery bank and single phase voltage source inverter (VSI). The dc-link voltage is maintained constant value of 48 V by controlling dc-dc converter with help of perturb and observe (P&O) algorithm based maximum power point tracker (MPPT). The VSI output voltage and frequency values are controlled based on grid parameters using PI controller and sinusoidal pulse width modulation (SPWM) technique. In this grid connected system is simulated and performances are analyzed through MATLAB software. The prototype experimental results are verified through 1 kW PMSG, 48 V battery bank with single phase grid connected system.
Volume: 10
Issue: 1
Page: 48-57
Publish at: 2021-03-01

Effect of thiourea on structure, morphology, and optical properties of spray deposited CZTS thin films for solar cell applications

10.11591/ijaas.v10.i1.pp39-46
Ramesh B. Mahewar , Ravikumar R. Vidule , Limbraj S. Ravangave
Cu2ZnSnS4 (CZTS) films of different Thiourea (SC (NH2)2) molarity were deposited by using a simple chemical spray technique at substrate temperature 275 °C. Analytical reagent Grade Copper chloride (CuCl2), Zinc chloride (ZnCl2), and Tin chloride (SnCl4.5H2O) were used as Cu+, Zn+, and Sn+ ion sources respectively and thiourea (SC(NH2)2) (0.02, 0.04, 0.06, 0.08, and 0.1 M) was used as an S- ion source. A set of five CZTS films was deposited using five different molarity of thiourea. The structure, morphology, elemental analysis, and optical properties of these films were studied using X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and UV-visible spectroscopy techniques respectively. The XRD spectra showed that all films are polycrystalline tetragonal structures with preferential orientation along 112 planes. The calculated crystallite size was increased with an increase in thiourea concentration. Variations of optical band gap with thiourea molarity have been investigated using Tauc plots. SEM micrographs exhibit CZTS spherical granules regularly arranged with some void spaces. The purity of deposited films was investigated using EDX analysis. All the CZTS films exhibit a higher absorption coefficient (α>104) cm-1 and a band gap in the reported range (1.2 to 1.53 eV) can be used as an absorber layer in solar cells.
Volume: 10
Issue: 1
Page: 39-46
Publish at: 2021-03-01

Successful online learning factors in COVID-19 era: Study of Islamic higher education in West Papua, Indonesia

10.11591/ijere.v10i1.21036
Agus Yudiawan , Budi Sunarso , Suharmoko Suharmoko , Fatma Sari , Ahmadi Ahmadi
This study aimed to map and tests the factors that influence online learning success in the COVID-19 era in Islamic Religious Higher Education in the West Papua region. Factors to be analyzed are student characteristics, internal motivation, instructor characteristics, quality of institutions and services, infrastructure and system quality, quality of courses and information, online learning environment. The sample size obtained from the Slovin formula was 302 students. Data collected through surveys by distributing questionnaires. Analysis of the regression model used to carry out data analysis. The results showed that the seven factors tested influenced online learning success in the COVID-19 era, with varying significance. Infrastructure and system quality are the most dominant influences (94.2%), while institutions' variety and services have no significant impact (6.3%). The conclusion is that the seven factors can be used to determine the success of online learning in the COVID-19 era in Islamic Religious Higher Education in the West Papua region.
Volume: 10
Issue: 1
Page: 193-201
Publish at: 2021-03-01

Deployment of internet of things-based cloudlet-cloud for surveillance operations

10.11591/ijai.v10.i1.pp24-34
Edje E. Abel , Abd Latiff Muhammad Shafie , Weng Howe Chan
This research proposes the design of internet of things (IoT) camera/toxic gas sensors for the surveillance of a nation’s borders. Also, a wearable radio frequency identification (RFID) tag with built-in body-temperature/heartbeat sensors, for monitoring the health status and locations of military personnel while on border patrol duty or in battlefield combats. Mobile micro-controllers are deployed to gather sensed data retrieved from the sensors/RFID tags and transmitted to a cloudlet situated at the command control center, located 200 meters away from the sensor devices. Consequently, sensed data are dispatch to the cloud data center when there is a need for offline data mining or analysis. The distinguishing feature of our proposed system from previous researches is that the health status and locations of troops (soldiers) are monitored while they are in border patrol duty or in battlefield combats. Also, the introduction of cloudlet services closer to the IoT sensor devices for collection of sensed data. This way, the sensed data or information gathered at the cloudlet will aid timely information retrieval that will speed up intelligence gathering for strategic military operations, especially in critical situations. This is an innovative attempt to apply IoT-enabled cloudlet-based cloud computing to support military operations.
Volume: 10
Issue: 1
Page: 24-34
Publish at: 2021-03-01

What network simulator questions do users ask? a large-scale study of stack overflow posts

10.11591/ijeecs.v21.i3.pp1622-1633
Syful Islam , Yusuf Sulistyo Nugroho , Md. Javed Hoss
The use of network simulator as a modern tool in analyzing and predicting the behaviour of computer networks has grown to reduce the complexity of its accuracy measurement. This growth of network simulator implementation have attracted the researchers and practitioners to share problems and discuss to improve the features. To communicate the issues relates to network simulators, users move to an online discussion platform, such as Stack Overflow. Although recent studies have shown the popularity and benefits of adopting network simulation tools, however, the challenges of using network simulator that users face remain mostly unknown. Therefore, in this paper, we examine 2,322 network-simulator-related Stack Overflow posts to provide insights on the topics that users are interested and the challenges they face. We apply the Latent Dirichlet Allocation topic modeling to understand the topics that are being discussed in Stack Overflow. Then, we investigate the popularity and difficulty of each topic. The results of this study show that users use Stack Overflow as an implementation guideline for network simulation model. We determine 8 discussion topics that are merged into 5 major categories. Most of the posts discuss simulation model configuration. We also observe that target network protocol modification and network simulator installation are the most popular topics among the users compared to other topics. Users are specially facing challenges on network simulator installation and target network protocol modification issues.
Volume: 21
Issue: 3
Page: 1622-1633
Publish at: 2021-03-01
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