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Current sensors to monitor water quality are made of manual sensors, which reported to have good performance. However, the major problems, which manual process to get the data. In addition, the data interpretation takes a long time. Due to these problems, a new approach needs to be introduced into the process to prevent a long data acquisition. Therefore, the SIAGA application was proposed. The application of SIAGA is divided into two main applications which are SIBA (Siaga Banjir) and SIAB (Siaga Air Bersih). We using WiFi system which is located at points along the flow of river. The result can be monitored in the online application based on smartphone which is divided into the river water quality, potential sources of pollution and flood area. Each WiFi point is completed with the instruments which are divided into the sensors that can do the identification of parameters to determine the water quality such as temperature, pH, water level and turbidity. This instrument completed using GPS (Global Positioning System), Full Map menu. The instrument was succesfully monitoredthe flood distribution and water quality in Bengawan Solo river. [ABSTRACT FROM AUTHOR]

Battery Charge Regulator (BCR) is needed for the solar power system generation. But the battery is often easily damaged due to the excessive charging current and the high temperature. This may the effect of the solar panel voltage being fluctuating and the fickle battery condition. Therefore it is necessary to manufacture BCR with constand current, the excessive voltage, and perform charging at a safe temperature. In this research BCR was made with constant current charging method. Current control is done using the MOSFET switching technique. In order to a constant current, closed loop control is used with a current sensor as a feedback sensor. The duty cycle of switching is regulated through a microcontroller based on the current read by the sensor. In addition, a temperature sensor and a voltage sensor are used as a feedback sensor so that charging runs safely. The results of the experiment show success withthe constantly maintained current at 1.5 A and 2 A. The battery temperature is lower than 40°C. The charge voltage is lower than 14.7 V. And the battery voltage is lower than 13.8 V. [ABSTRACT FROM AUTHOR]

Disinfection of a room is very important to note, especially because of the presence of the coronavirus which has been confirmed to be able to spread through the air, stick to objects around it and has a high potential to transmit the virus. This is exacerbated by the presence of a new variant of the coronavirus which causes an increasing number of people to be exposed every day. One of the most effective disinfectants is ozone. Ozone is a gas formed from three oxygen atoms which is highly reactive and more unstable than oxygen. Ozone with the right concentration of about 1 ppm can kill pathogens, such as bacteria and viruses. This research focuses on designing an independent control and monitoring system based on Human Machine Interface (HMI). This control and monitoring system design can be applied to measure ozone concentration and is equipped with a timer and automatic mode. The test results obtained total accuracy value of this device with variables of voltage, current, generator temperature, ambient temperature in the box, humidity in the box, and ozone concentration is 97.3%, while total precision value is 98.5%. This research was conducted by testing the appliance in a 1.2 x 1.5 x 2.5 m room for 10 minutes and the results showed that the voltage used by the appliance is in the range of 216V to 219V with a current dropping from 0.56A to a stability point of 0.46A. The maximum temperature at the generator is around 96oC with an ambient temperature of 38°C, the humidity decreases from 81% to 68% and the ozone concentration produced can be stable around 1 ppm in 1 minute which can be used to kill bacteria and viruses. [ABSTRACT FROM AUTHOR]

Electrical energy is the key in the development of human civilization, it causes an increase in electricity production using fossil fuels. This causes the emergence of the need for commissioning Solar PV plants in large scale. The large scale of the project has the problem of land requirement needed for the project that not always available. Installing the Solar PV plants on water bodies like oceans, lake, and reservoir can be an interesting option. Floating type solar panel can have a numerous advantages, one of them are the increase in power yield while also lowering the working temperature of the solar panel. Test carried to measure the influence of floating method by measuring the performance of the solar panel. The data shows that by using this method there has been an increase in power yield by 30.54%. However in regard of temperature, an increase of 6.42% occurred at the time of testing. [ABSTRACT FROM AUTHOR]

Lithium-ion is used in battery electric vehicles as an effective and efficient energy storage medium. The energy density and life cycle of Lithium-ion battery are better than lead-acid batteries. But for Lithium-ion batteries, like every other battery, when operating in a high discharge current which causes an increase in battery temperature. This increase in temperature causes degradation in the performance of available electrical capacity of the battery. An experimental method was carried out to determine the effect of discharging current of the 18650 Lithium-ion cells to the surface temperature of the battery. The first measurement was carried out on a cell by installing three temperature sensors to measure the surface temperature distribution of the battery. The temperature sensors are each installed at 16mm (point A), 32mm (point B) and 48mm (point C) from the positive end of the battery. The initial treatment before the Lithium-ion cell test is charging up to a voltage of 4,2Vdc, then drained to a voltage of 2,7Vdc. Constant discharging currents are applied to the cells i.e. 3.5A, 7.5A, 11A, and 15A, respectively. The second measurement was carried out on a battery module consisting of 35 cells arranged in 7 cells in series and 5 cells in parallel (7S5P). Each temperature sensor is installed in the center of the cell (point B). The cell with the sensor was put in the middle of the series or parallel of the battery module. Before the discharge current, the battery module is charged to a voltage of 29.4Vdc. Constant discharge current is applied to the battery modules i.e. 15A, 20A, 25A, and 30A, respectively. The result of the temperature measurement of a cell (point B) to time shows that the 15A discharge current produces the highest temperature compared to 3.5A, 7.5A, and 11A. The temperature at point A has a lower tendency compared to points B and C. The temperature of point D in the direction of the series and parallel arrangement shows a tendency for higher temperatures compared to other points. This condition indicates that the highest temperature concentration of the battery module is in the middle of the battery cell arrangement. [ABSTRACT FROM AUTHOR]

Transistors are the most important part in the development of microprocessor systems. However, the size of transistor cannot be reduced again due to its material size limitation. A new type of transistor is needed, namely single electron transistor (SET). This transistor transports electrons one by one through the quantum dot (QD) using the coulomb blockade effect. SET can be used to make low-power quantum computing device. This research simulates the effect of capacitance in double quantum dots single electron transistor (DQD-SET) using SIMON 2.0. There are two configurations of DQD-SET; series and parallel systems. This simulation uses an experimental approach where the current sensor is placed close to the drain. The value of middle capacitance (CM) and tunnel junction capacitance (TJ) of DQD-SET configurations are varied to observe changes in I - V characteristics. As a result, capacitance values of CM and TJ affects to the current rate change i.e., number of peaks and peak value which is associated with the distance of QD. When the value of CM decreases, an additional current appears between the two initial current peaks. This happens due to clustering effect on QD. [ABSTRACT FROM AUTHOR]