This research aims to know the effect of the Rotor Radius Ratio on the performance of the hybrid Vertical Axis Wind Turbine Savonius-Darrieus NREL S809 model using the Computational Fluid Dynamics method. Two-bladed Savonius is used as an internal rotor, and three-bladed Darrieus NREL S809 as an external rotor. Turbine model performance is analyzed through the value of the Moment Coefficient and Power Coefficient. The result shows that the increase in the Rotor Radius Ratio value causes an increase in the initial Moment Coefficient but a decrease in the maximum Power Coefficient value. At the initial TSR, the Rotor Radius Ratio 0.5 model has the best Moment Coefficient value among all variations but has the lowest maximum Power Coefficient value.

Control strategy has an important role in electric vehicles. It determines the efficiency and performance of electric vehicles. This study analyzes the control strategies on electric vehicles by a bibliometric analysis using VOSviewer, Open Refine and Tableau Public software. In this study, the dataset was taken from Scopus. The number of articles used is 1403 documents. The keywords used in Scopus database based on TITLE-ABS-KEY (title, abstract, keyword) are "control strategy" AND "electric vehicle" OR "EV". Based on the result analysis, the number of studies on control strategies in electric vehicles continues to increase from 2013 to 2022. Result analysis of this study provides information that the latest research trend related to control strategies in electric vehicles is wireless power transfer, switched reluctance motor, energy consumption, robust control, disturbance observer, battery life, deep reinforcement learning, reinforcement learning, ECMS and fuzzy logic control. We find that the most influential and productive authors are from China.

The potential for solar and wind energy at YIA Airport is quite large so that it can be used as a renewable alternative energy source. Based on data obtained from BMKG of YIA, the average sun intensity at YIA Airport is 6.21 kWh/m2 while the average wind speed is 3.07 m/s. This potential can be used as solar and wind hybrid energy to meet some of the electricity demand at YIA Airport using photovoltaic modules and wind turbines. Design of the wind turbine refers to research conducted by Mihai Lates and Radu Velicu (2014), which implements a basic savonius type wind turbine with an aspect ratio (α) 2, diameter (D) 3.50 m, number of blades (n) 2. Solar array design uses an off-grid system, then will be hybridized with the wind turbine. Based on the calculation result shows that the required area of the solar array is 2282.87 m2 to produce 2574 kWh/day, while the number of turbines proposed is 143 units to produce 136.90 kWh/day. With this design and based on the calculation, electrical energy will be generated for 13.55% (2710.90 kWh/day) of the total electricity demand at YIA Airport.

The purpose of this community service activity is to introduce the Python programming language to teachers and students of vocational school in Purwakarta exploiting an application to create a simple graphical user interface (GUI). Python is a programming language that is currently trending. The training was carried out in 3 stages, namely preparation, implementation and evaluation. As a result, participants were able to follow this training well and were able to create their own version of a simple GUI. Participants were also able to integrate their GUI with Arduino. After this activity, participants are expected to be able to explore how to make simple GUI using the modules that have been given.

Bibliometric analysis research has been done for vertical axis wind turbine (VAWT). This study aims to determine the growth of VAWT research, the number of VAWT studies in various countries and the most influential authors to find opportunities for research collaboration, and the challenges of future VAWT research. Research data was taken from Scopus in 1801 articles from 1970-2021. The software used for data interpretation was VosViewer 1.6.19 and Tableau Public 2022.2. Based on the analysis, VAWT research has tended to increase from 1970-2021, although there was a decrease from 1987-2006. The country that has conducted the most VAWT research is China, while the author with the highest number of citations is from Italy. The most dominant research topic related to VAWT research is computational fluid dynamics (CFD), which is 50.14 % of the total. A future challenge related to VAWT research is finding a suitable turbulence model for each type of VAWT or finding an airfoil optimization method so that a model with betterperformance is obtained. Opportunities for research collaboration can be carried out with China or an author with the highest number of citations who has expertise in the field of CFD.