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Designing an onshore wind farm layout poses several challenges, including the effects of terrain and landscape characteristics. An accurate model should be developed to obtain the optimal wind farm layout. This study introduces a novel metaheuristic algorithm called Modified Electric Charged Particles Optimization (MECPO) to maximize wind farms' annual energy production (AEP) by considering the different terrain and landscape characteristics of the sites. Some non-uniform scenarios are applied to the optimization process to find the best combination of decision variables in the wind farm design. The study was initiated by a uniform wind farm layout optimization employing identical wind turbine hub heights and diameters. Following this, these parameters underwent further optimization based on some non-uniform scenarios, with the optimal layout from the initial uniform wind farm serving as the reference design. Three real onshore sites located in South Sulawesi, Indonesia, were selected to validate the performance of the proposed algorithm. The wind characteristics for each site were derived from WAsP CFD, accounting for the terrain and landscape effects. The results show that the non-uniform wind farm performs better than its uniform counterpart only when using varying hub heights. Considering the impacts of the terrain and landscape characteristics, it is observed that sites with a higher elevation, slope index, and roughness length exhibit a lower wake effect than those with lower ones. Moreover, the proposed algorithm, MECPO, consistently outperforms other algorithms, achieving the highest AEP across all simulations, with a 100% success rate in all eight instances. These results underscore the algorithm's robustness and effectiveness in optimizing wind farm layouts, offering a promising avenue for advancing sustainable wind energy practices. [ABSTRACT FROM AUTHOR]

Renewable energy sources play a great role in the sustainability of natural resources and a healthy environment. Among these, solar photovoltaic (PV) systems are becoming more economically viable. However, as the utility of solar energy conversion systems is limited by the availability of sunlight, they need to be integrated with electrical energy storage systems to be more sustainable. This paper aims to improve the control performance of a hybrid energy storage system (HESS) with PV power generation as the primary power source. HESSs stabilize DC microgrid systems by compensating for demand generation mismatches. Batteries and supercapacitors are chosen as energy storage elements; batteries have a high energy density and are capable of supplying and absorbing energy over a long duration, while supercapacitors can store and deliver energy very quickly. To enhance the stability of the system, each storage element is connected to the DC bus using a bidirectional Ćuk converter, which offers high efficiency, a continuous current, and minimal switching losses. This study proposes a proportional–integral (PI) controller combined with the fast nonsingular integral terminal sliding mode control (FNITSMC) for HESSs to adjust the power balance in a DC microgrid. FNITSMC has the advantage of enhancing the system states to reach the equilibrium point of a long sliding surface with a fast convergence rate. The reference current for FNITSMC is obtained using a PI controller combined with a low-pass filter (LPF), which eliminates the peaking current spikes on the battery and diverts them towards the supercapacitor. The effectiveness of the proposed control scheme is validated through the real-time hardware-in-the-loop (HIL) simulations on Typhoon™ HIL-402 with added uncertainties, including load variations at various temperatures and irradiances. [ABSTRACT FROM AUTHOR]

A hybrid generator is one of the attempts to reduce carbon emissions in electricity generation, as it could replace the combustion system currently used in generator sets to generate electricity while increasing carbon emissions. In the hybrid generator system, Lenz's rule of electromagnetic induction is applied in reverse by using a relay to change the polarity of the solenoid coil's electric current. The permanent magnet in the solenoid coil generates mechanical energy (motion) and thereby moves the generator engine, since the permanent magnet is connected to the generator engine via the crankshaft. The objective of this study is to determine and compare the behaviour of N55, N52, N42, N42SH, and samarium-cobalt permanent magnets for the magnet system. The objective of this study is also to find a suitable permanent magnet for use in the magnet system to increase the power generation efficiency. A simple model is simulated to achieve the desired result, including magnetic flux density inside and around the magnets, magnetic field strength calculation, and applied force. The simulations and analysis are performed using ANSYS R19 software and finally all the data are recorded and compared to select the best magnet and develop a prototype. The permanent magnet inside the solenoid plays an important role in the hybrid generator and it is crucial to choose the suitable permanent magnet to increase the efficiency of power generation. From the data, Alliance N-55 permanent magnet has the highest magnetic force of 131.57 N for 1 mm because it has significantly higher magnetic flux density, magnetic flux intensity and magnetic force. [ABSTRACT FROM AUTHOR]

This paper presents a multi-technique approach for the purpose of recording and documentation of cultural heritage. The focal point of the study is to generate a three-dimensional (3D) model representation of a physical object and to apply orthographic projection to document the design. Three main methods are used to generate 3D objects, namely Laser Range Scanner, Depth Image Data, and Photogrammetry. A comparison analysis is designed to evaluate each method accordingly. For evaluation purposes, a case study is designed where a scale model of a 25-cm-long famous historic Portuguese Indian Armada, known as "Flor de la Mar" is selected as a sample for generating 3D model records. The comparison analysis shows that the Photogrammetry method is superior in terms of detail, precision, and visualization. On the other hand, Laser Range Scanner and Depth Image Data method can display the data into the point cloud but with less accuracy. Overall, the result shows that the Photogrammetry method achieves a strong 97.6% of accuracy in terms of dimensions and shapes. [ABSTRACT FROM AUTHOR]

Rambutan and pulasan seeds are usually discarded as waste. However, the seeds contain a significant quantity of quality crude fat. Therefore, the present work was conducted to establish and compare the fat properties, and saponin and total phenolic contents of fermented rambutan and pulasan seeds. Results showed that the crude fat yields for rambutan and pulasan seeds were 3.98 and 7.41 g/10 g, respectively. Results also showed decreases in crude fat by 41% for rambutan seeds, and 23% for pulasan seeds after fermentation. The yields of the main fatty acid in rambutan and pulasan seeds, which was oleic acid, were 53.11 and 58.27%, respectively. Only 0.81 and 37.25% of triacylglycerols remained in rambutan and pulasan seed fats, respectively after fermentation. In addition, the melting temperature for both seed fats increased, while the saponin and total phenolic contents in rambutan and pulasan seeds decreased with increasing fermentation time. [ABSTRACT FROM AUTHOR]