The main problem with electricity supply on densely populated islands is reliable, low-carbon, and sustainable electricity. The availability of potential energy needs in-depth observation to ensure that the system can be built sustainably. This paper examines the integration of PV systems and diesel power systems on Karimunjawa Island to meet the need for reliable systems from economic, ecological, and technological aspects. Using the DigSilent Power Factory program to obtain the system response interference and penetration of the Photovoltaic (PV) system. Furthermore, this paper also tests short circuit analysis and economic feasibility analysis while validating the Levelized Cost of Electricity (LCOE) and Electric Production Cost (EPC) approaches. The results show that the availability of irradiation can handle the electricity needs on Karimunjawa Island. In addition, it proposes the designed requirements for an integrated PV power system and Diesel Power Plant (DPP) system. The research has also captured the synergistic profile of PV and DPP working coordination within 24 h.

The aim of this study is to investigate and analyze the NdFeB N52 type magnetic field distribution on a Trapezoidal type coil in an axial type generator. The main problems addressed by this study are how the distribution of magnetic field type NdFeB N52 to the trapezoidal type coil and how the influence of air gap between NdFeB N52 magnets and the coil to the output electric voltage generated from the coil at the speed of rotation. In order to answer the problems, we moved a rectangular type magnet axially towards the trapezoidal type coil with a specified distance, so that we could identify the change of the output voltage. The description of the magnetic field distribution in the stator was simulated by using the Maxwell 3D Design application ran in ANSYS software 16.0. The result of this study shows that the magnet was distributed evenly on the coil. It is also known that based on experiments with 2mm to 6mm of magnet to coils of gaps, the highest output voltage is at 2mm gaps at 750rpm.

Online quality analysis technique of energy consumption is getting easier. It is because the sensor module and microprocessor are getting more simple, complex and possess high accuracy. This study offers an alternative to online electrical energy consumption monitoring technique by using Arduino. It is interesting to know the accuracy of the work of the Arduino-based energy quality monitoring system with high accuration measurments tool Kyoritsu power analyzer KEW 6315 and Hioki 328-20. The method of this research is the design of 1 phase electrical energy monitoring system by using current sensor type SCT-013 and voltage sensor in the form of transformator. EmonLib Library was used for processing voltage and current data in Arduino. The validation of measurement results was done by comparing the results of Arduino with Kyoritsu KEW 6315 and Hioki 328-20. The measurement reporting technique was displayed online based on the website. The results provide a clear picture of the measurement performance of the developed system, that the system has a quality of performance close to Kyoritsu type kew 6315 that against Hioki 328-20 with an average error below 5% is acceptable. The results of the measurement of electrical energy consumption had been successfully displayed in the form of a website-based energy report.

This paper discusses a proposed system for measuring athletic agility based on Internet of Things (IoT) technology. The problem with existing agility gauges is that they still use a stopwatch to measure time, and the existing tools only have a few pads and a short distance. The main objective of this paper is to propose the design of an agility measuring system that is simpler and has the ability to coordinate with more motion sensor nodes. This paper also presents the design results of activity diagrams, transaction databases, block diagrams, and hardware configurations of motion sensor nodes. The result of this research is an IoT-based agility measuring system using the ESP8266 module, allowing 253 or more pads to be coordinated. The activity diagram consists of three main actors, namely admin/tester (coach), tester trainer (observer), and athlete actor. In the database design of this IoT-based agility measuring system, it consists of 6 tables, namely three master tables and three transactional tables. The three master tables are the "athletes" table, the "mater_pad" table, the "test_scheme" table. Meanwhile, the three transactional tables are the "test_log" table, the "test_pad" table, the "test_agility" table.