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S. Lale, Mateo Bašić, S. Lubura, Božidar Popović, M. Ikić

This paper proposes a battery emulator based on a bidirectional non-inverting buck-boost power electronics converter. With the capability of bidirectional operation, it can emulate both charging and discharging processes. The proposed emulator is controlled with the advanced I2 dual current-mode control (I2DCMC) algorithm, combined with a feedforward control, which ensures fast and accurate tracking of the voltage and current characteristics of the batteries. The emulator is universal in terms of the various mathematical models of the batteries, which can be implemented in real time. It has no limitations regarding different battery types. Detailed analysis and the design procedure of the proposed battery emulator are presented. The performances of the emulator are validated with simulation and experimental results for three battery types: polymer Li-ion, conventional Li-ion, and lead–acid battery. Both steady and transient states are analyzed, especially transitions between charging and discharging phases. The possibility of simple time scaling of charging/discharging processes is successfully achieved and demonstrated, which is very important in making tests faster, with preserved battery characteristics. Considering its low-cost and user-friendly operation, the proposed emulator can be a good alternative to the real batteries in experimental tests of different power electronics systems. The prototype, which is developed for the experimental verification of the emulator, is designed for and limited to the research of lower power ratings systems of up to 100 W. It is suitable in education to easily demonstrate the behavior of the batteries in multiple scenarios in controlled laboratory conditions.

The complete classification of the saddle-point solutions for high-order above-threshold ionization, presented in and for a linearly polarized laser field, is generalized to the case of an arbitrary bichromatic elliptically polarized field. We first present the classification of the saddle-point solutions for the case of a monochromatic elliptically polarized driving field, which is the simplest example of the field that has two components, i.e., that evolves in the plane. For a bichromatic laser field whose elliptically polarized components have the frequencies rω and sω (r and s are integers, s>r, and ω is the fundamental frequency), the system of the saddle-point equations has 8s2 solutions per optical cycle. One-half of these solutions are the so-called backward-scattering solutions for which the direction of the electron motion is significantly affected by the rescattering. The other half are the forward-scattering solutions for which the electron is only slightly deflected during the rescattering event. For some specific field configurations, the number of saddle-point solutions can be smaller. For example, for a bicircular field, which consists of two counterrotating circularly polarized components, there are 4s(r+s) solutions, while for the corotating configuration there are 4s2 solutions. As an application, we have shown that for a monochromatic elliptically polarized laser field, all four threshold anomalies appear in the spectra of the rescattered photoelectrons.

Jaeyong Lee, Zuwan Lin, Wenbo Wang, Jongmin Baek, Ariel J. Lee, Almir Aljović, Arnau Marin-Llobet, Xinhe Zhang et al.

M. Benedikt, F. Zimmermann, B. Auchmann, W. Bartmann, J. Burnet, C. Carli, A. Chanc'e, P. Craievich et al.

Nataša Trkulja, Artur Hermann, Paul Lukas Duhr, Echo Meissner, Michael Buchholz, Frank Kargl, Benjamin Erb

Connected and automated vehicles rely on data from various entities to support safety-critical applications such as Cooperative Adaptive Cruise Control (CACC). However, unauthorized data manipulation through, for example, data injection attacks can compromise vehicle safety and lead to incidents. Existing vehicular security mechanisms, such as Misbehavior Detection System (MBD), have limitations in detecting and mitigating all types of threats on their own. To address these limitations, our prior work has proposed the concept of a Trust Assessment Framework (TAF), which assesses data trustworthiness by combining evidence from multiple security systems operating as trust sources. However, TAF as a concept has not been extensively evaluated in safety-critical Cooperative Driving (CD) applications. In this work, we refine the architecture of the TAF and implement a software prototype based on it. We integrate the TAF prototype with a CACC simulation environment and implement three types of data injection attacks. We demonstrate that by incorporating multiple security mechanisms as trust sources, the TAF significantly improves attack detection performance and reduces the number of crashes by 86% compared to using a single security mechanism, such as MBD.

Zijad Dzafic, Jozo Bejic

Authors in this paper investigates the relationship between the business environment and the operating performance of the plastic products manufacturing sector intended for the construction industry in Bosnia and Herzegovina (BiH). The focus is placed on how regulatory and institutional conditions impact economic indicators such as sales revenue growth, profit, export earnings, total assets, and employment. Since empirical studies in this area are scarce, this research contributes to filling an important academic gap. The study relies on both secondary and primary data sources. First, the business environment of BiH is evaluated using reports. Second, financial and operational data were collected for the top 20 companies in the plastic products manufacturing sector for the construction industry in BiH. The analysis covers the period 2015–2024, using indicators of revenue, profit, exports, total assets, and number of employees. A trend analysis was conducted to identify growth patterns, while a qualitative assessment was applied to connect these trends with the conditions of the business environment. The analysis of company performance reveals a positive growth trend in all major economic categories. Sales revenue steadily increased between 2015 and 2024, reflecting growing demand in the markets. Profitability improved despite regulatory barriers, indicating a strong adaptive capacity of firms. Export earnings expanded, showing that plastic product manufacturers. Total assets of the companies grew significantly, suggesting reinvestment and capacity expansion. Employment levels also increased, underscoring the sector’s contribution to job creation. These results support the hypothesis of a significant impact of the plastic products manufacturing industry on economic performance indicators in BiH.

Yuexi Lin, Muniba Bhatti, Michael Shola David, Yannic Brasse, Jann Harberts, Thomas Kister, Muamer Dervisevic, Tobias Kraus et al.

Wearable electrochemical biosensors offer a promising alternative to conventional invasive blood‐based methods for monitoring biomarkers in diagnostic or therapeutic applications. Microneedle (MN)‐based technology provides direct access to the skin's interstitial fluid (ISF), enabling real‐time monitoring of biomarkers. Nevertheless, current micro‐ and nanofabrication techniques do not adequately support the development of MN‐based wearable technology that can utilize soft hybrid conductive inks, limiting its use in transdermal biosensing. Herein, an MN‐based biosensing platform is developed by integrating 3D printing, soft lithography, and hybrid conductive ink technology, featuring a fenestrated MN shell (FMNS) that serves as a protective layer for the inner hybrid conductive ink coating and prevents delamination during skin application. This FMNS patch demonstrates a wide pH monitoring range, high selectivity and accurate detection of subtle ISF pH changes, safe integration of hybrid conductive inks, and reduced fabrication time and cost when compared to other microfabrication methods such as lithography and deep reactive ion etching. The biosensor excels in protecting the biosensing layer and demonstrates excellent analytical performance in monitoring changes in pH levels of the skin ISF. This micro‐ and nanofabrication approach has great potential in integrating hybrid conductive ink technology into transdermal wearable devices for health monitoring and diagnostics.

A. Greljo, Ajdin Palavri'c, Mirsad Tunja, J. Zupan

We chart new-physics models that produce exotic, high-multiplicity muon decays featuring prompt or displaced $e^+e^-$ pairs and/or photons, with or without missing energy, such as $\mu \to 5e$, $\mu \to 7e$, etc. Starting from an effective-field-theory perspective, we estimate the reach on the ultraviolet scale and identify conditions under which lower-multiplicity modes are suppressed or occur at comparable rates. We then construct explicit realizations in minimal dark-sector models with light, feebly interacting particles, such as flavor-protected scalars, dark photons, inelastic dark matter, and axion-like particles. The predicted novel signatures can be probed at MEG II and Mu3e, as well as during calibration runs of COMET and Mu2e. A future discovery would provide valuable insights into short-distance dynamics and the mechanism of lepton-flavor symmetry breaking.

Marta Narigina, A. Tihak, A. Romānovs, Dušanka Bošković, Y. Merkuryev

In computational cardiology, a paradigm shift has occurred with the transition from static cardiovascular risk assessment to dynamic, customized modeling. A hybrid conceptual framework for AI-based digital twins is presented in this paper, which combines simulation models informed by physics and datadriven perception models in a synergistic way. For conditions like myocardial infarction and stroke, this strategy seeks to provide previously unheard-of possibilities for disease prediction, real-time cardiovascular monitoring, and customized treatment optimization. Key elements of the framework include graph neural networks (GNNs) for modeling vascular topology, physicsinformed neural networks (PINNs) for hemodynamic analysis, and multi-scale mathematical underpinnings. We illustrate a crucial first step toward the realization of a comprehensive digital twin that is based on physiological first $p$ rinciples a nd responsive to real-time data by validating the data-driven perception module.

This study aims to determine the antioxidant and antibacterial potential of aqueous extracts of six different plant species, which are widely used in traditional medicine: Salvia officinalis L., Mentha longifolia (L.) Huds., Urtica dioica L., Rosmarinus officinalis L., Rubus fruticosus L. and Achillea millefolium L. The samples were collected in the Tuzla region between March and July 2025. All of the mentioned plants are important in traditional medicine and have been previously reported to have biological activity. The antioxidant activity was tested by the DPPH and FRAP methods, while the antibacterial potential was tested by the diffusion technique on reference bacterial strains from the WDCM collection. The extracts showed high antioxidant activity, with nettle and sage extracts showing the most potent in neutralizing DPPH radicals. Weak to moderate antibacterial activity was recorded in the case of nettle, sage, mint and rosemary extracts, and a complete absence of activity in the case of yarrow and blackberry leaf extracts.

S. Gajip, T. Martinović, S. Huseinbegović, Amer Smajkic, M. Ćalasan, M. Petronijević

This paper presents the development and validation of a computation model of a cascaded multilevel power inverter as an initial step toward creating a high-fidelity digital twin. A preliminary overview of the cascaded multilevel inverter topology is provided, followed by introducing a mathematical modeling approach that uses graph theory to derive the system's nodal equations. The computation model is implemented in a programmable environment, and its output is compared to the MATALB/Simulink-based simulation, which serves as a reference for performance evaluation. The evaluation is performed using the mean square error (MSE) metric to quantify the accuracy of the proposed model. Results indicate a close agreement between the computation model and simulation data, confirming the model's potential for integration into future real-time digital twin architectures for power converter control and diagnostics.

Karlijn Demers, N. van den Bergh, B. Bongers, S. V. van Kuijk, Z. Mujagic, D. Jonkers, M. Pierik, Laurents P. S. Stassen

BACKGROUND Inflammatory bowel disease (IBD) may negatively affect health-related physical fitness. However, the development of interventions to improve health-related physical fitness and thereby disease outcomes is hindered by insufficient evidence. This study compared health-related physical fitness between patients with IBD and healthy control subjects, examined associations with disease and treatment characteristics, and explored patients' perspectives. METHODS In this cross-sectional study, 105 patients with IBD and 102 age- and sex-matched healthy control subjects performed validated tests for body fat (4-site skinfold thickness), cardiorespiratory fitness (steep ramp test), muscular strength (steep ramp test, 60-second sit-to-stand test, hand-held dynamometry), muscular endurance (isokinetic dynamometry), and flexibility (sit-and-reach test). Data on disease and treatment characteristics, fatigue, physical activity, and patients' perspectives were collected. RESULTS Patients with IBD had higher body fat (29.5% vs 26.9%; P = .012), lower steep ramp test performance (peak work rate 4.2 W/kg vs 4.8 W/kg; P < .001), fewer sit-to-stand repetitions (42 vs 47; P = .002), and reduced hamstring strength (3.0 N/kg vs 3.2 N/kg; P = .011) compared with healthy control subjects. This was associated with higher age, female sex, higher body mass index, fatigue, arthritis, and multiple biologicals used. Most patients considered physical fitness important and beneficial for their symptoms, and the majority expressed interest in professional support. CONCLUSIONS Patients with IBD have higher body fat and reduced cardiorespiratory fitness and muscular strength compared with healthy control subjects. Especially, patients with a higher age, female sex, higher body mass index, fatigue, arthritis, or multiple biologicals used are at risk for such impairments and may benefit from physical exercise interventions.

Abaz Velić, Z. Karadžin

The negative impacts of the old mining operations both in our country and throughout the world represent one of the biggest environmental problems. The analysis of the previous practice in Bosnia and Herzegovina regarding the closure of mines in the past decades lead to the conclusion that very few were closed in accordance with the regulations. The problem was further complicated by the war that took place in our country from 1992 to 1995 which in certain number of cases led to the sudden stoppage of mine operations, many of which did not continue to operate even after the cessation of war activities. In the period 2013-2014 the Japanese Agency for International Cooperation (JICA) did an initial analysis of black industrial spots (Hot spots) in the Federation of Bosnia and Herzegovina and 4 such locations were determined , one of which was the former mine in Vareš. The mine consisted of several units at different locations where various types of raw mineral materials were exploited , which made reasearch even more difficult. This primarily refers to the location of surface mine (SM) „Smreka“, the ore processing and packing plant at SM „Veovača“ and the water accumulation with flotation tailings. For the mentioned sites, a field inspection and analyses of the existing condition were carried out to obtain results required to serve as a basis for proposal of measures to reduce the impact on the environment as well as the rough estimate of the relating remediation costs, which were done separately for each of the research polygon sites. It should be emphasized that Bosnia and Herzegovina's accession to European Union implies significantly stricter environmental protection practices in the mining industry as well. Today, environmental protection in mining is an international standard and obligation. At the same time, the need should be pointed out to the contribution of each country in reducing the negative impact on the environment and climate changes. Key words: abandoned mines, environmental risks, measures to reduce environmental impacts, remediation

The main task of the multi-purpose reservoir "Modrac" is to regulate the water regime in a given basin while making decisions on the amount of water released, as well as the amount of water that needs to be retained for future use. Decisions are made on the basis of available data and forecast data. Since no forecast model has been developed, the operator of these complex processes must rely on forecasts that are more or less precise. In practice, dam and reservoir operators, in most cases, usually follow the rules of the curves (volume, flow, etc.), which determine the actions to be taken depending on the current state of the system. With the construction of the Modrac dam in 1964, the reservoir of the same name was formed. The primary goals were to provide technical water for industry in the Tuzla region and mitigate downstream floods, as well as recreation and other purposes. The paper presents an analysis of the runoff coefficient in the correlation of annual precipitation and mean annual inflows for the catchment area of the multipurpose reservoir "Modrac" for the period 1999 - 2024. Keywords: multipurpose reservoir, runoff coefficient, precipitation, inflow, catchment area

Munir Jahić, Amir Mešković, Mufid Tokić, Omer Kovčić

In a series of exogenous and endogenous processes that cause enormous damage almost all over the world, land erosion and torrential flows occupy a special place. Torrential flows are formed practically unnoticed and represent a mixture of a large amount of eroded material from mountainous and hilly areas, which, together with water, flows down the ravines formed at a high speed into the lower parts. These streams, which in dry weather have very little flow or their beds are completely dry, in a short period of time destroy everything in front of them, from bridges, roads, to other buildings. They fill canals and agricultural land with silt, and often endanger populated areas, often with human casualties. A true example of the above was witnessed in the destruction of settlements in the municipality of Konjic and municipality of Jablanica in October 2024, where torrential rains caused huge human losses and material damage in a few hours.

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