esa-sceva/satcom-chunk-collection huggingface dataset:
###### Abstract  
The aim of this study was to determine the effect of a cow's breed on the content of minerals in milk depending on the stage of lactation. The study material was the milk of cows of two breeds, Montbeliarde (mb; \(n=15\)) and black-and-white Polish Holstein-Friesian (phf; \(n=15\)), kept at the same farm. The phf cows were matched with the mb cows by analogs considering the stage and number of successive lactations. Milk for analysis was collected six times during lactation when the official test milking was performed, and a total of 180 milk samples were collected. The fresh milk was analyzed for its proximate chemical composition and mineral content (Ca, Mg, K, Na and Zn), which were identified in the mineralization by flame atomic absorption spectrophotometry. Milk of the Montbeliarde cows contained significantly more sodium, calcium, magnesium and zinc compared to milk of the Polish Holstein-Friesian cows. This enables the conclusion that the contents of these elements are determined by breed. This study demonstrates the variability of the contents of the analyzed minerals with time after calving. During lactation, the contents of potassium, calcium, magnesium and sodium were the highest at the late stage of lactation, especially in the tenth month of lactation.  
macroelements; zinc; cow's milk; breed; Montbeliarde +
Footnote †: journal: Applied sciences
## 3 Interoperability for Wide-Area Applications
### R-SV for Wide-Area Measurement  
Traditional Supervisory Control and Data Acquisition (SCADA) systems receive measurements data from remote devices every few seconds. However, current Synchronized Measurement Technology can provide hundreds of samples of data per second. This technology consists of four components: Phasor Measurement Units (PMU), Phasor Data Concentrator (PDC), time-synchronization source from GPS, and a communication network. While a PDC is located in the control center, PMUs are deployed at substations.  
In each substation, the PMU connects to the substation Local Area Network (LAN) and sends synchrophasor data (time-synchronized wide-area measurement data) to the remote PDC via [17] WAN. The PDC processes the wide-area measurement data and forwards it to the WAMPAC application. Many legacy PMUs use the IEEE C37.118.2 communication framework for WAN communication with the PDC. One drawback with this communication is its cybersecurity vulnerabilities [18] since there is no built-in security mechanism in the IEEE C37.118.2 framework. To counter this, IEC 61850-90-5 published a communication framework for secure transmission of synchrophasor data (measurement data such as voltage, current, frequency, etc.) based on the IEC61850 data model and communication services. IEC 61850-90-5 R-SV is a suitable solution [3; 19; 20] for transferring wide-area measurement data between PMUs and PDCs in an interoperable and secure manner. R-SV messages contain measurement data modeled on the IEC61850 data model and secured by defined security mechanisms in IEC61850-90-5. R-SV messages can be applied for Coordinated Voltage Control (CVC) schemes that aim to optimize system voltage by receiving measurements from different locations. One such setup for CVC that could utilize R-SV communication is presented by authors in [21].
# Bangla Character Detection Using Enhanced YOLOv11 Models: A Deep Learning Approach
## 2 Related Work
### Different Bangla Alphabet or Character Datasets Using Different Models  
Among the various techniques employed for Bangla alphabet recognition shown as Table 1, our approach, utilizing ResNet-50 with transfer learning, demonstrates exceptional performance in terms of both accuracy and versatility. Achieving an accuracy of 96.12% on the Banglalekha-isolated dataset, which includes 84 distinct classes, our model significantly outperforms other methods that either use fewer classes or report lower testing accuracies.  
For instance, although [PERSON] et al. [15] achieved a 99% accuracy, their model was tested on only 50 classes, thus reducing the complexity of the classification task. Similarly, while [PERSON] et al. [16] reported high accuracy (96% for character recognition and 91% for word recognition), their results were split across different recognition tasks, making direct comparisons less straightforward. The integration of ResNet-50 with transfer learning in our model facilitates more effective feature extraction and enhances its ability to generalize across datasets with diverse character variations. As such, our model stands as a more robust and effective solution for Bangla character recognition compared to the other approaches examined.
## 3 Results and Discussion
### Sn PP Electrodes Based on In-House GDLs
After 19 h of CO2 electrolysis at 50 mA\(\cdot\)cm\({}^{-2}\), the Sn catalyst layer on top of the sample was completely dissolved, large agglomerates were found inside of the GDL, and the GDL thickness increased from 0.9 mm to 1.4 mm (Figure 7b). In the SEM image (Figure 5c), the dark grey areas represent the GDL (Spectra 6, Figure S8a). EDX measurements in some lighter areas on the surface and inside of the GDL (Spectra 5, Figure S8b) revealed the presence of large amounts of K and O. During the long-term  
Figure 5: Investigations of Sn-IH-PP GDE. **(a)** SEM images of Sn-1-11-60; **(b)** SEM images of Sn-1-55-200; **(c)** FE for formate and product distribution for the electrodes with electrodeposited catalysts Sn-1-11-60 and Sn-1-55-200, as well as an electrode with a precipitated Sn catalyst. Electrochemical tests conditions: 200 mA\(\cdot\)cm\({}^{-2}\), 50 \({}^{\circ}\)C; time on stream (TOS): 60 min. electrolysis, secondary products such as carbonates or bicarbonates were formed in a non-Faradaic side reaction at high pH values in the pore systems of the used electrodes. These carbonate salts precipitated inside the GDL and increased its thickness through the process of swelling. [PERSON] et al. [34] also observed SnO\({}_{2}\) leaching from the same in-house fabricated GDL, where the Sn catalyst was not electrochemically deposited but instead had Sn particles finely deposited on the carbon black via a homogeneous precipitation method with urea. According to the Pourbaix diagram of Sn [80], metallic Sn is the thermodynamically stable phase at these potentials at a pH value of at least 10. It must be mentioned that due to the generated OH' ions during the ongoing reactions of eCO\({}_{2}\)RR and HER, the pH value inside the GDL can significantly exceed the value of 10 [66]. It seems that at such high pH values, and due to the negative potential, the metallic Sn is not stable. Sn dissolves, and over time, less catalyst is available in the deposited layer of the Sn electrocatalyst. Finally, no catalyst remains on the surface (see Figure 7b,c). To summarise, these results indicate that Sn is not stable as a catalyst for eCO\({}_{2}\)RR at high current densities. Locally high pH values undoubtedly cause the dissolution of Sn. This can be unambiguously concluded to be due to the complete dissolution of the electrodeposited Sn layer at these conditions. Figure 6: Product distribution of the Sn-IH-PP GDE, Sn-1-11-60. Electrochemical tests conditions: 50 mA\(\cdot\)cm\({}^{-2}\), 50 \({}^{\circ}\)C, 19 h.  
Figure 7: Sn-IH-PP GDE, Sn-1-11-60: (**a**) CT cross-section of Sn-IH-PP-GDE before electrolysis; (**b**) CT cross-section of the Sn-IH-PP-GDE after 19 h of electrolysis; (**c**) SEM cross-section of the electrode after 19 h of electrolysis at 50 mA\(\cdot\)cm\({}^{-2}\) at 50 \({}^{\circ}\)C with the secondary products inside the GDL.
# An Evaluation of the Demineralizing Effects of Various Acidic Solutions
## 1 Introduction  
Dental caries is a multifactorial chronic disease caused by the interaction of four major factors: microorganisms, substrate, host factors and time [1]. It is caused by the action of organic acids produced during the metabolism of carbohydrates by aciduric bacteria [2]. Glyolysis (acid production) lowers the pH of the surrounding area and leads to the demineralization of dental tissue [3]. The acidic environment eventually causes a cavity on tooth surfaces [4].  
When the pH in the surrounding environment decreases, the solubility of the dental enamel increases significantly. The solubility of hydroxyapatite (HAP) crystals increases 10 times with a drop of each pH unit [5, 6]. When the pH drops under the value of 6, chemical dissolution of both the organic and the inorganic components takes place. This is enhanced by the water content of the tooth, which facilitates the infiltration of acid and the wash-out of minerals from the enamel [7]. During dental demineralization, calcium and phosphorus ions are drawn out from the hydroxyapatite, which has the following chemical formula: Ca\({}_{8}\)(PO\({}_{4}\))\({}_{3}\)(OH) [8, 9, 10].  
Dental enamel demineralization is a chemical process. The dissolution of hydroxyapatite can be described as  
\[\text{Ca}_{10}(\text{PO}_{4})_{6}(\text{OH})_{2}+2\text{H}^{+}\rightleftharpoons 10\text{Ca}^{2+}+6\text{PO}_{4}{}^{3-}+2\text{H}_{2}\text{O}\]\[\text{PO}_{4}{}^{3-}+\text{H}^{+}\rightleftarrows\text{HPO}_{4}{}^{2-}\text{ or }\text{H}_{2}\text{PO}_{4}{}^{-}\text{ or }\text{H}_{3}\text{PO}_{4}\]  
The consequences of enamel demineralization are as follows:  
An increase in interprismatic space;  
A change in the orientation of hydroxyapatite crystals and occurrence of abnormal forms;  
An expansion of the porosities of the enamel, which leads to higher penetrability of the dental tissue [11].  
Optical changes (white spot lesions) occur due to the increased pore spaces between the thinned rods, which modify the refractive qualities of the enamel [12]. Simulating enamel demineralization is a complex task, and some of the steps can be accomplished using digital instruments, as in the finite elements method [13; 14; 15; 16].  
The purpose of this work is to evaluate which of the techniques and acids that are included in this study can induce artificial caries lesions in the most natural way. This is important for a better understanding of their etiology and could assist further research in finding alternative treatment options. Diagnosing and being able to treat dental caries and erosions in their early stage is essential in preventive and minimally invasive dentistry. Therefore, the null hypothesis is that all the acidic solutions (the independent variable) used in this in vitro study can create lesions for which there are no statistically significant differences (\(p<0.05\)) compared to the healthy enamel, selecting as dependent variables the \(\Delta\)E and the DIAGNODent(tm) values. Rejecting the null hypothesis could prove which acids and viscosities can mimic natural dental decay or erosion.
###### Abstract  
The application of renewable energy is stimulating since the environmental pollution and the increase in demand for global energy consumption have become the main concerns of humanity. However, the intermittent nature of renewable sources could seriously affect the frequency stability of the system which needs to be solved. In this paper, the Virtual Synchronous Generator (VSG) based on battery/supercapacitor Hybrid Energy Storage System (HESS) is proposed to handle the stochastic power output of Photovoltaic (PV). First, the power allocation methods for HESS and its comparison are illustrated. Second, the comparison of the frequency deviation suppression strategies is presented. Moreover, as the adjustable parameters of VSG (\(J\), \(D\)) is a key superior to the conventional synchronous generator; hence, a part of this paper will be introduced a new evolutionary algorithm called Backtracking Search Optimize Algorithm (BSA) to tune the parameters of the VSG in real time. To investigate the control performance, the standalone microgrid is modeled in the MATLAB/Simulink environment. Several case studies are conducted, and the results prove the improvement of the system frequency by attenuating the maximum overshoot of frequency deviation from 50.18 Hz to 50.03 Hz.  
backtracking search optimize algorithm; frequency fluctuation; hybrid energy storage system; power allocation method; virtual synchronous generator
## 1 Introduction
### Main Contributions  
The studies regarding the decision-making tools integrating expert systems presented in the literature have highlighted various approaches that solve different technical issues from EDNs at various voltage levels. However, very few references refer to voltage control in LVEDNs, which use expert systems, and these with applications in passive LVEDNs.  
In this context, the authors propose an efficient and resilient voltage control solution based on an expert system to remove the over-voltage and under-voltage issues in PV-rich active LVEDNs. The main contributions are the following:  
* Proposing another principle compared to the LDC method (used in all current solutions) to solve the decreased/increased voltage issues based on the data performed by the smart meters installed at the end-user level. The OLTC modifies the tap to ensure that the voltages at the end-user level remain inside the range [\(-10\%\), \(+10\%\)] at least 95% of the time slots.
* Developing an expert system, including rule-based reasoning, with the main advantages: the \"fast-scanning\" of the input data, identification of voltage issues that come up, and determination of a solution associated with the tap position of the OLTC that does not violate the voltage constraints in the PV-rich LVEDNs. The voltage constraints are verified based on the deviations between the reference voltage and the voltages recorded in the nodes in each time slot recognizing the excesses of the allowable limits, regardless of the power flow's direction.
* Designing a data management framework including a real-time query procedure that uploads data from the smart metering system (SMS) and network data systems (NDS) and saves them in two partitions (static and dynamic) from the knowledge database. The design allows a high speed of data processing.
* Performing an in-depth analysis in a real LVEDN belonging to a Romanian DNO based on more scenarios characterized by the three indicators: the penetration degree of the PV prosumers, the consumption evolution associated with the consumers, and the energy production of the PV systems installed to the prosumers. The number of combinations between the possible values of the three indicators led to 75 scenarios that cover all spectrums of the operating regimes of the LVEDNs.
# Dynamic Low-Emission Zones for Urban Mobility: A Systematic Review
## 4 Results
### Technological Innovations  
Technological innovations are pivotal in defining and implementing dynamic Low-Emission Zones (LEZs), ensuring adaptability, efficiency, and public acceptance. The referred studies show the transformative role of blockchain technology, cryptographic security, dynamic pricing, and real-time data analytics in enhancing LEZ operations. Blockchain-based access-control systems improve privacy preservation and fraud detection, while electronic road pricing (ERP) with dynamic tolling optimizes traffic flow and emission management. Advanced sustainability assessment tools integrate real-time monitoring and predictive modeling, enabling data-driven policy adjustments.  
4.3.1 Security and Privacy in a Blockchain-Powered Access Control System for Low-Emission Zones [26]  
This study proposes a decentralized Low-Emission Zone (LEZ) management system that addresses the limitations of traditional access-control schemes reliant on centralized entities. The proposed system ensures enhanced privacy, security, and system availability by utilizing blockchain technology and smart contracts. The main contributions proposed are as follows:  
* Decentralization of Access Control: The system replaces centralized entities with a blockchain-based distributed network, eliminating single points of failure and improving transparency in managing vehicle accesses and fee payments.
* Privacy Preservation: Unlike conventional camera-based systems, which capture indiscriminate license plate data, this approach guarantees user anonymity unless fraudulent behavior is detected. Honest drivers retain their privacy throughout the process.
* Smart Contract Implementation: Vehicle entries and payments are processed as blockchain transactions through smart contracts. This ensures automated, tamper-proof fee calculations and payments using digital currencies.
* Secure Fraud Detection: Fraudulent users can be identified and penalized without compromising the privacy of compliant users. The system provides revocable anonymity and integrity for all recorded transactions.
* Performance Validation: Extensive laboratory and real-world low-traffic street-environment testing confirmed the system's feasibility. The smart contract's gas consumption was analyzed, demonstrating the approach's cost-effectiveness.  
This blockchain-powered access-control system addresses critical challenges in dynamic LEZ implementations, such as scalability, user trust, and efficient fee collection. Its decentralized and privacy-preserving features make it a valuable foundation for future dynamic LEZ strategies.
## 6 Limitations and Challenges in Passkeys
### Challenges
#### 6.1.1 Technical Challenges
The use of default attestation reveals device-specific information, such as the manufacturer and model, and metadata associated with public keys, such as key handles, which in turn can inadvertently aid in account linking attacks, especially if combined with timing or side-channel attacks [80]. However, developers often avoid requiring attestation due to privacy concerns, leading to reliance on less robust forms like self-attestation, which are more susceptible to certain attacks [81]. Mitigation suggestions emphasize limiting the use of attestation to scenarios where it is strictly necessary and anonymizing data wherever possible [80]. Without proper configuration, this can otherwise be exploited to track users across services. One paper highlighted that in modern operating systems and browsers, forensic data can give clues about the user's authentication processes with FIDO2 passkeys, therefore compromising the user's privacy [78]. More specifically, this forensic data may allow for detecting linked devices, which might inadvertently expose user accounts and authentication processes [29; 80]. The paper also noted that additional artifacts are generated when external devices (e.g., smartphones) are used for the authentication process, leading to the distribution of digital traces across multiple locations. This is different from password-based authentication, where little to no traces are left behind in the authentication process [78]. Continuing on the note of privacy, certain privacy safeguards, such as Direct Anonymous Attestation (DAA), are not mandatory in the FIDO2 specification, leading to further inconsistent implementations [80]. If advanced privacy features like DAA were made mandatory, it would aid in ensuring consistent privacy protection across implementations and protect users' privacy [80]. Addressing privacy issues requires both mandatory protocol changes and the widespread adoption of advanced privacy-preserving techniques. Here, formal verification emerges as a crucial tool for identifying and addressing such vulnerabilities [80]. These insights from academic literature suggest that while FIDO2 provides high-security guarantees, there are still existing issues that need to be addressed, like the above-mentioned incomplete standardization and issues regarding privacy protections due to inconsistent implementations. Finally, although passkeys are resistant to phishing, they can still be exploited through sophisticated social engineering tactics targeting recovery mechanisms or user devices [6,79]. In addition, websites supporting FIDO2 authentication often allow fall-back to weaker second-factor alternatives, e.g., OTPs, exposing users to real-time phishing attacks. Attackers can exploit this by relaying credentials and inducing users to input OTPs under the guise of additional security, effectively bypassing the stronger FIDO2 authentication [82].
# Synthesis and Properties of Octet NiCr Alloy Lattices Obtained by the Pack Cementation Process
## 3 Results and Discussion
### Microhardness  
Figure 6 shows the microhardness of the lattices with different compositions. The average microhardness of the pure nickel lattice was 90 HV, which was roughly equal to that of the Ni foam Dunand used to make NiCr and NiCrAl alloys [10,20]. It was lower than the microhardness of an electroplated Ni lattice (295 HV) [25]. This was because  
Figure 4: TEM microstructure of the Ni-23 Cr alloy lattice: (**a**) bright-field image of the NiCr alloy lattice, (**b**) enlarged view of the red area in (**a**).  
Figure 5: EDS results of NiCr alloy lattices with different compositions: (**a,e**) Ni-16 Cr; (**b,f**) Ni-23 Cr; (**c,g**) Ni-34 Cr; (**d,h**) Ni-45 Cr, (**i–l**) EDS mapping of the Ni-45 Cr lattice cross section.  
electrodeposited Ni had an ultra-fine grain structure, and the growth of the grains occurred during the annealing process at 900 \({}^{\circ}\)C.  
The microhardness of Ni-16 Cr, Ni-23 Cr, Ni-34 Cr and Ni-45 Cr alloys was 135 HV, 180 HV, 280 HV and 363 HV, respectively. The microhardness of the NiCr alloy lattice increased with the increase of Cr content. Compared with the microhardness of the annealed Ni lattice, the microhardness of the Ni-45 Cr alloy lattice was about four times higher. This was attributed to the solution strengthening provided by the Cr element, which increased with the increase of Cr content. This trend was observed for the NiCr alloy foams [10], but the microhardness of the NiCr alloy in this paper was higher.