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Recent Submissions

A double resistive-capacitive approach for the analysis of a hybrid battery-ultracapacitor integration study
(MDPI, 2025) Chmielewski, Adrian; Piórkowski, Piotr; Bogdziński, Krzysztof; Krawczyk, Paweł; Lorencki, Jakub; Kopczyński, Artur; Możaryn, Jakub; Costa-Castelló, Ramon; Ožana, Štěpán
The development of energy storage systems is significant for solving problems related to climate change. A hybrid energy storage system (HESS), combining batteries with ultracapacitors, may be a feasible way to improve the efficiency of electric vehicles and renewable energy applications. However, most existing research requires comprehensive modelling of HESS components under different operating conditions, hindering optimisation and real-world application. This study proposes a novel approach to analysing the set of differential equations of a substitute model of HESS and validates a model-based approach to investigate the performance of an HESS composed of a Valve-Regulated Lead Acid (VRLA) Absorbent Glass Mat (AGM) battery and a Maxwell ultracapacitor in a parallel configuration. Consequently, the set of differential equations describing the HESS dynamics is provided. The dynamics of this system are modelled with a double resistive-capacitive (2-RC) scheme using data from Hybrid Pulse Power Characterisation (HPPC) and pseudo-random cycles. Parameters are identified using the Levenberg-Marquardt algorithm. The model's accuracy is analysed, estimated and verified using Mean Square Errors (MSEs) and Normalised Root Mean Square Errors (NRMSEs) in the range of a State of Charge (SoC) from 0.1 to 0.9. Limitations of the proposed models are also discussed. Finally, the main advantages of HESSs are highlighted in terms of energy and open-circuit voltage (OCV) characteristics.
Design and analysis of automatic whole row tomato seedling transplanter technology with integrated controlling system
(Wiley, 2026) Ali, Addisu Negash; Nigus, Messele Gashaye; Paramasivam, Velmurugan; Petrů, Jana; Čep, Robert
In the small-scale farming, transplantation of tomato is performed manually using hand drilling without considering the standard agronomy practices. To develop innovative products with reduced size and automatic operations, the analysis and design of the feeding, picking, and planting components of the automatic transplanting machine need to be the focus area. The integrated approaches of conceptual design, concepts evaluation and selection, synthesis and numerical modeling of mechanisms, path manipulator design, components and assembly SolidWorks modeling, Matlab and ADAMS software validation simulations, and PLC based control system design are used to develop the target technology. During design and analysis, a 128 cell standard plug tray, 42 mm grid depth, 110 mm average seedling height, 35 cm plant spacing, 40 cm row spacing, and 192 seedlings/min planting capacity were selected as design criteria. The results from kinematics analysis and optimal design of gripper indicated that the clamping and insertion angles should be in the ranges of 16 degrees-22 degrees and 10.6 degrees-14.8 degrees respectively to prevent damage. Furthermore, the optimum clamping angle (beta) and insertion angle (alpha) were found to be 20 degrees and 13.4 degrees respectively for successful clamping and picking of seedlings. A combination of linear and fourth order polynomial models have been developed to provide accurate trajectory plans for the path manipulator. The ADAMS software simulation results are directly fitted with the theoretical results, and the modeling of the seedling pickup mechanisms provides a basis for future bench tests. For a standard 128 cells plug tray, and target frequency of 192 seedlings/min, the pickup device with eight grippers is designed to effectively pick the whole row of tomato seedlings within 2.5 s. Finally, to synchronize the transplanting operations and ensure a continuous supply of signals, photoelectric positioning sensors, magnetic switches, pneumatic components, and PLC control unit are selected and positioned at the optimum locations.
IndiVNet A region adaptive semantic image segmentation for autonomous driving in unstructured environments
(Springer Nature, 2025) Chakraborty, Pritam; Bandyopadhyay, Anjan; Bhattacharyya, Siddhartha, Siddhartha; Platoš, Jan
Autonomous navigation in developing regions is challenged by heterogeneous traffic, dynamic occlusions, and weak road structure. Existing segmentation models, largely trained on structured Western datasets, struggle to generalize under these conditions. To address this gap, we propose IndiVNet, a semantic segmentation architecture tailored for unstructured Indian driving environments. IndiVNet introduces a progressive dilation encoder (616) that captures fine-grained details and broad contextual cues without inducing oversparsity. Evaluated on the India Driving Dataset (IDD), it achieves 69.98% mIoU, outperforming CNN and Transformer baselines, and reaches 73.2% mIoU on CAMVID, demonstrating strong cross-domain generalization. By combining contextual adaptability with real-time efficiency, IndiVNet offers a scalable, region-aware solution for robust autonomous navigation in complex environments.
Thermoelectric power factors of defective scandium nitride nanostructures from first principles
(Elsevier, 2026) Cigarini, Luigi; Wdowik, Urszula D.; Legut, Dominik
The thermoelectric properties of scandium nitride are strongly influenced by structural and electronic factors arising from defects and impurities. Nevertheless, the mechanisms by which these microscopic features affect transport are not yet fully understood. Experiments show a large variability in the electronic transport properties, with a strong dependence on the experimental conditions, and attempts to improve thermoelectric efficiency often lead to conflicting effects. In this work, we employ the Landauer approach to analyze the effects of different kinds of structural defects and impurities on electronic transport in scandium nitride. This approach allows us to relate the transport mechanisms to the structural and electronic modifications introduced in the lattice, with atomistic resolution. In light of these new insights, we propose a rationale relating part of the experimental variability to its microscopic origin.
Development of optimally reinforced glass/bamboo fiber and rice husk/bagasse filler Agrostone composite panels for interior panel applications
(Wiley, 2026) Ali, Addisu Negash; Yityaw, Abebaw Abiyu; Paramasivam, Velmurugan; Rao, D. K. Nageswara
Agrostone panels, popularly used for interior walls in construction, are usually made from sustainable agricultural waste such as bagasse as filler and glass fiber as reinforcement in a binder of pumice, MgO, and MgCl2 solutions. The present work has gone ahead of one step by adding rice husk and bamboo fiber, which are abundantly available in Ethiopia, in addition to bagasse and glass fiber. It is aimed to investigate the effect of rice husk and bamboo fiber additives. Initial optimized parameters are obtained for two variables in three levels from the central composite design (CCD), and the samples are prepared for the design of experiments. Regression analysis and ANOVA are conducted using the experimental data. The data from ANOVA is fed to response surface methodology (RSM) to obtain the final optimized proportions of reinforcement fibers and fillers for the highest mechanical properties without changing the proportions of matrix materials. Using the proportions from RSM, the specimens are prepared for the final evaluation of mechanical properties. Weight percentages of bamboo fibers (0, 1.1, and 2.2) and rice husk (0, 3.515, and 7.03) are given by RSM. The optimization process in CCD consists of three levels for two variables in terms of weight percentage. The results show that 3.091 and 1.358 wt.% of rice husk and bamboo fiber, respectively, gave the highest tensile, compressive, flexural, and impact strength values of 64.92 MPa, 75.534 MPa, 65.168 MPa, and 63.485 J, respectively. The corresponding comparable values from the experiment are 65.02, 74.73, 73.42, and 63.95 MPa, respectively.