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Demand for electricity is increasing rapidly, the consequence of this is a threat to the stability of the electrical system, one of which is the voltage stability. FACTS or flexible alternating current transmission system is an electronic equipment capable of regulating electrical power transmission that can be used to overcome stability problems. This research will analyze the use of SVC and STATCOM as an equipment model from FACTS to overcome the stability of the electric power system on the most critical buses. Simulations were carried out using PSAT using case studies: a 500 kV Java-Bali network. Then the stability of the voltage is observed using the help of the PV curve which can show the value of the voltage conditions in each operating condition. SVC installation in the Java-Bali 500 kV case does not reduce the active power losses or reactive power, but also the addition of length λ is 0.233 p.u. (6.01%) and compared to the addition of length λ at STATCOM of 0.149 p.u. (3.85%). [ABSTRACT FROM AUTHOR]

The use of electrical energy on industrial loads often cause energy consumption problem which is not in accordance with the power needed by loads. The problem is caused by low loads power factor rating. Therefore, power factor correction is required by calculating installed loads capacity with the resulted power factor. Power factor correction can be done by using a magnetic energy recovery switch (MERS). MERS is a circuit located between sources and loads which control switching process on the capacitor. MERS is arranged of four MOSFET or IGBT as the switch. This research is done to know the characteristics of MERS and simulate it to correct the power factor of static loads. Static load is symbolized as RL. The specification of the load is obtained from research reference. This research implements MERS on a renewable energy source. The result of this research proves that MERS can correct static loads power factor from 0, 47 to 0, 98. The implementation on a renewable energy source showed if MERS is able to increase the value of static loads power factor. [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]

Nowadays, 4G LTE (Long Term Evolution) telecommunication technology that has spread throughout Indonesia is growing rapidly. However, the coverage of 4G LTE has not been implemented well in Indonesia, one of them is in Sragen. So to be able to increase the quality of 4G LTE network, it is necessary to optimize the coverage area of 4G LTE network in Sragen by using the physical tuning method, which is to adjust the antenna tilt, azimuth antenna, power. Key Performance Indicator is a reference to determine the performance of a network. The measured parameters are reference signal reception power (RSRP), reference signal reception quality (RSRQ), signal interference noise ratio (SINR). The results from the optimization are the percentage of RSRP was initial 45.87% to 75.58%, an increase of 29.72%. While the RSRQ value increased by 20.78%, with an initial value was 27.84% to 48.62%. SINR increased by 5.29% with an initial percentage was 4.87% to 10.16%. [ABSTRACT FROM AUTHOR]

Technology in sector communication is growth rapidly, which is marked by the increasing number of facilities offered, for example the growth of data, voice and video communication. The technology that can answer these communication demands is Long Term Evolution Adavanced (LTE-A) technology. To optimize the quality by using a combination of frequencies on LTE-A. This research comparing results of non-Carrier Aggregation (Non-CA) and Carrier Aggregation (CA). The frequency band that use existing frequency one of cellular operator in Surakarta 1800MHz and the additional frequency for CA2100 MHz. The result shows signal level value is above th threshold -80 dB increasefrom 89.51 to 96.04%. The percentage of reviewed RSRP if the value is above threshold -105 dBm increased from 83% to 95.44%. the parameter of distribution SINR in percentage values are above threshold above 5dB increased from 47.22% to 69.67%. The value of the mean throughput increase from 25.41 Mbps be 37.31 Mbps, with target KPI 12 Mbps. The number of rejected user in the network decreased from 2.2% to 0.6%. Parameters that are reviewed in this research can meet the target KPI. [ABSTRACT FROM AUTHOR]

Water pollution in developing countries continues increase every year, almost every river as one of water sources have been polluted from low to high levels. Polluted river water unconsciously used by agricultural business actors as an irrigation source for their agricultural land which indirectly causes damage for yielding and planting media. In order to find out the quality of irrigation water used, a minimum parameter of quality of irrigation water is needed, namely pH, TDS, and temperature. The parameter value is sent to smartphone via Bluetooth connection and can also be accessed through the website because the device can be connected to the internet. The parameter data can be stored in graph files or tables. This device successfully measures pH, TDS, and irrigation water temperature accurately with an accuracy rate of + 5% with an optimal distance of 7 meters with Bluetooth connection and with a 720 mAh battery, this device can be used continuously for 2 hours in full working condition. Energy usage when device is fully work are 1.09 watts. This device can continuously monitor the quality of irrigation water used, so agricultural entrepreneurs can control the water used for irrigation sources better. [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]