esa-sceva/satcom-chunk-collection huggingface dataset:
## Materials and Methods  
### Data  
#### 2.1.1. TechDemoSat-1 Space GPS Receiver Remote Sensing Instrument Data  
Positioning the specular reflection point requires the use of the transmitter and the receiver positions. In order to avoid introducing uncertainties from the orbit simulation, and to facilitate reference, the transmitter and the receiver positions contained in the dataset of the Space GPS Receiver Remote Sensing Instrument (SGR-ReSI) carried by the TDS-1 satellite are used to position specular reflection points which are then compared with those also contained in the dataset. The TDS-1 satellite was launched on 8 July 2014, the orbital altitude is 635 km and the inclination is 98\({}^{\circ}\). The GNSS-R payload of the TDS-1 consists a zenith-pointing antenna for receiving direct GPS signals,  
Figure 1: The Global Navigation Satellite System Reflectometry (GNSS-R) reflection reference surface and the specular reflection point, where \(T\) is the transmitter, \(R\) is the receiver, \(S\) is the specular reflection point with the WGS-84 ellipsoid as the reflection reference surface, and \(S^{\prime}\) is the specular reflection point with geoid as the reflection reference surface.  
a nadir-pointing antenna for receiving reflected GPS signals, and the remote sensing receiver SGR-ReSI, which continuously records the integration midpoint time and the corresponding receiver space coordinates. The SGR-ReSI also records the integration midpoint time of the four reflected signal receiving channels when capturing reflection. These two kinds of integration midpoint times are saved in the Level-1 metadata with the corresponding GPS satellites and the derived specular reflection points space coordinates (the TDS-1 data are obtained from: [[ftp://ftp.merrbys.co.uk](ftp://ftp.merrbys.co.uk)]([ftp://ftp.merrbys.co.uk](ftp://ftp.merrbys.co.uk))) [36]. For extracting the positions, we need the receiver space coordinates when capturing reflection, these reflections are filtered out when the two kinds of integral midpoint times are the same by comparison. In order to achieve statistically significant results based on sufficient time and space coverage, we used a total of 4,492,927 reflections from all the 944 tracks of April 2018.  
The position of the specular reflection point in the TDS-1 satellite dataset takes the WGS-84 ellipsoid as the reflection reference surface. The calculation method is as follow [36]:  
1. Applying the coordinate transformation to scale the WGS-84 ellipsoid to a sphere of unit radius in polar and equatorial axes independently. The positions of the transmitter and the receiver are scaled to the new coordinate system by the same transformation.
2. Then the specular reflection point position is calculated using the standard sphere as the reflection reference surface.
3. The inverse of the coordinate transform is applied to scale back to the original ellipsoid.
# AI-Driven Adaptive Communications for Energy-Efficient Underwater Acoustic Sensor Networks
## 3 System Description  
We assume an underwater wireless sensor network where two nodes, A and B, are equipped with cameras, temperature sensors, light intensity sensors, and depth sensors. These nodes monitor water conditions in an area rich of marine species, as illustrated in Figure 1. Delivering information about critical species passages is essential for tracking migrations and preserving ecosystems. When data must be relayed beyond the underwater domain, connectivity can leverage terrestrial networks or other wireless systems, depending on coverage and requirements.  
Underwater nodes must be smart and capable of promptly identifying marine species. By performing on-node classification, nodes dynamically adjust transmission parameters (e.g., modulation, transmission power, packet size, etc.) to minimize environmental disturbance. For example, rare species trigger low-rate modulation schemes for reliability purposes (e.g., BPSK) and smaller packet sizes to reduce noise pollution, while common species recognition allows for the use of higher spectral efficiency modulations (e.g., QPSK) for faster and larger data delivery. Transmission power is also tuned accordingly: lower power increases BER but avoids excess noise, while higher power increases throughput at the risk of harming marine life. Background noise from acoustic communications can cause behavioral changes, hearing damage, or physical harm to marine animals, as evidenced by documented cases linking mid-frequency sonar to cetacean strandings [14].  
In our envisioned underwater monitoring system, the use of a distributed AI-based approach is essential due to the unique constraints of underwater environments. Traditional centralized systems, which rely on surface-based processing, cannot support real-time inference or dynamically adapt to the transmission parameters without overwhelming the limited bandwidth and exhausting energy resources. To address this, our design embeds lightweight AI models directly into sensor nodes, enabling on-node classification of marine species and real-time adjustment of transmission parameters (e.g., switching to BPSK modulation in case of monitoring of rare species). Each underwater node captures images,performs local species identification, and transmits only the classification result to the central station or to the neighbor node. This approach reduces data traffic, minimizes acoustic noise pollution, and aligns with ecological preservation goals. By decentralizing intelligence, the system avoids the pitfalls of centralized architectures, thereby avoiding bandwidth demands and risking harm to marine life through excessive acoustic traffic. Thus, distributed AI ensures scalability, energy efficiency, and environmentally responsible operation--critical requirements for sustainable underwater monitoring.
# Modeling and Analysis of Contactless Solar Evaporation for Scalable Application
## 2 Methodology
### Experimental Setup  
To verify the effectiveness of the proposed modelling framework, a laboratory SCE device was fabricated, tested and compared with the modelling results. Test rigs of the laboratory device are represented in Figure 4, containing a solar simulator, the foam topped with a reflector, an absorber-emitter, a container with pure water, a balance, three thermocouples, a data acquisition unit and a PC. The absorber-emitter was prepared as follows: Firstly, the copper plate was drilled uniformly and then polished and etched to achieve high absorptance of sunlight. Then, the emitter side was sprayed with black paint (Zynolyte Hi-Temp Paint; Aervoe) to achieve a high-emissivity paint. The solar simulator (_Sciencetech_, UHE-NS-100) was fixed and provided with a stable solar flux of 1000 W\(\cdot\)m\({}^{-2}\). Three thermocouples were placed at the top surface (\(T_{\text{wat-t}}\)) and bottom surface (\(T_{\text{wat-b}}\)  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Value** & **Parameter** & **Value** \\ \hline \(T_{\text{wat}}\) (\({}^{\circ}\)C) & 25 & \(\alpha_{e}\) (\%) & 96.32 \\ \(T_{\text{w}}\) (\({}^{\circ}\)C) & 25 & \(\varepsilon_{e}\) (\%) & 78.20 \\ \(T_{\text{amb}}\) (\({}^{\circ}\)C) & 25 & \(\varepsilon_{wall}\) (\%) & 95 \\ \(\varphi_{\text{emb}}\) (\%) & 50 & \(h_{\text{fg}}\) (kJ kg\({}^{-1}\)) & 2500 – 2.386 \(\times\) (T-273) \\ \(\varphi_{\text{wat}}\) (\%) & 100 & \(D\) (m\({}^{2}\) s\({}^{-1}\)) & \(1.87\times 10^{-10}\) (T/K)\({}^{2/02}\)/(P/atm) \\ \hline \hline \end{tabular}
\end{table}
Table 2: Input parameters for the 3D COMSOL Multiphysics models.  
Figure 3: Independence study of mesh for scalable SCE.  
of the bulk water, and the bottom surface of the absorber-emitter (\(T_{\text{ae}}\)) for measurement of temperatures. A weighing balance (_Sartorius_, GL22021--1 SCN) was used to assess the change in mass of water as a proxy for evaporation rates. The data acquisition unit (_Toprie_, TP700) logged the signals from measuring instruments and monitored the readings.
## 4 Monitoring System Testing and Analysis
### Measurement Performance Test and Analysis of State Parameters
#### 4.2.2 Voltage Test  
This test required a high-voltage transmission line with the regulator and step-up transformer for the simulation, using a ratio of 1:120 step-up transformer, one end of which is connected to the high-voltage lead, one end of which is connected to earth. The  
\begin{table}
\begin{tabular}{l c c c c c} \hline \hline \multirow{2}{*}{**Methods**} & \multirow{2}{*}{**Avg. Acceptance Rate vs.**} & \multicolumn{2}{c}{**Acceptance Rate**} & \multicolumn{2}{c}{**Network Survival Time (s)**} \\ \cline{3-5}  & & **Burst Data Nodes** & **100 Nodes** & **200 Nodes** & **100 Nodes** & **200 Nodes** \\ \hline ODMT & 98.6286 & 81 & 80 & 898 & 1803 \\ EGRPM & 98.6286 & 50 & 39 & 942 & 1841 \\ MECA & 91.8571 & 55 & 46 & 1034 & 2005 \\ EEDD & 76.0429 & 78 & 62 & 1026 & 2017 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Numerical results of the experiments.  
Figure 6: Network generation time.  
monitoring terminal was suspended at 4 m, and this was followed by a multimeter to obtain the voltage regulator readings of input voltage, \(U_{1}\), and voltage sensor output voltage, \(U_{2}\); Table 6 shows the voltmeter readings. The two values, \(U_{1}\) and \(U_{2}\), are closely related to each other; thus, with the voltage sensor at a height of 4 m, the input voltage and output voltage difference ratio of about 5% and the value of distributed capacitance to the ground close to stable, demonstrate that the output voltage sensing monitoring is also relatively good.
## 3 Results and Discussion
### Biological Activity of AmPS
#### 3.2.2 Antioxidant Activity  
The total antioxidant potential of AmPS was investigated using the ORAC assay and the ABTS\({}^{\bullet+}\) scavenging activity. The results of both assays are expressed in Trolox equivalents per mass of AmPS (Table 3). Crude polysaccharides from honey mushroom were found to possess antioxidant activity at a level of 414.3 uM TE/g and 94.69 uM TE/g in the ORAC and ABTS assay, respectively. Previous results for crude polysaccharides from a different edible mushroom _S. crispa_ revealed activity at a level of 168.51 uM TE/g in the ORAC assay [10]. This demonstrates that the polysaccharide fraction from _A. mellea_ shows significantly higher activity. The results obtained by [PERSON] et al. [23] showed that polysaccharides from wild _A. mellea_ demonstrated a dose-dependent antioxidant effect in various assays, including ORAC and FRAP as well as DPPH\({}^{\bullet}\) and ABTS\({}^{\bullet\bullet}\) scavenging activity. They found that two purified polysaccharide fractions exhibited ORAC values at levels of 2126.53 uM TE/g and 1791.05 uM TE/g. With regard to the ABTS\({}^{\bullet\bullet}\) scavenging activity, polysaccharides at a concentration of 2 mg/mL reduced 49.72% and 68.91% of the radical, while Trolox (a highly efficient antioxidant molecule) was found to reduce 99.02%. The reducing properties of _A. mellea_ polysaccharides (determined with the ABTS assay) reported previously by [PERSON] et al. [30] revealed that IC\({}_{50}\) values of the four polysaccharides isolated from wild sporophores and cultured products of honey mushroom varied from 885.7 to 2118 ug/mL and were lower than for positive controls (15.79 ug/mL for vitamin C and 29.82 ug/mL for BHA). The differences between our and previous results indicate that mushroom fruiting bodies of various origins possess different polysaccharide structures, which affects their biological activity. Certainly, further studies on the relationship between the composition and structure of polysaccharides in relation to their activity are needed to reveal the mechanisms of action.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Sample** & \(\alpha\)**-Glucosidase** & \(\alpha\)**-Amylase** \\ \cline{2-3}  & & **EC\({}_{50}\) (mg/mL)** \\ \hline AmPS & 0.73 \(\pm\) 0.02 & n.d. \\ Acarbose & 1.37 \(\pm\) 0.01 & 0.01 \(\pm\) 0.02 \\ \hline \hline \end{tabular} Mean values from three replicate determinations with standard deviation; n.d.—activity not detected.  
\end{table}
Table 2: EC\({}_{50}\) values of \(\alpha\)-glucosidase and \(\alpha\)-amylase inhibition by the AmPS.
# Design of a Device Based on an LED Matrix for Water Sterilization
## 2 Materials and Methods
### Effect of LEDs on Water Temperature  
The effect of LEDs on water temperature was measured using a thermometer in 10 mL of deionized distilled water in contact with different LEDs at the following time intervals: 0 min, 1 min, 2 min, 4 min, 8 min, 16 min, 32 min, 64 min, 90 min, 2 h, 3 h, and 6 h.  
Following the construction of an array of LEDs, their effect on temperature was assessed by placing the thermometer inside a flask containing 1 L of deionized distilled water, and measuring the temperature at the following intervals: 0 min, 1 min, 2 min, 4 min, 8 min, 16 min, 32 min, 64 min, 90 min, 2 h, 3 h, and 6 h.
## 3 Results and Discussion
### Hardened State Properties
#### 3.4.6 Carbonation  
Figure 10 presents the results of the carbonation test, wherein the samples were exposed to a 5% CO\({}_{2}\) environment for 91 days. The results of the RC were not included as carbonation depths were all under 1 mm for the duration of the test. As expected, carbonation increased with the incorporation of MIBA as partial FA replacement; however, contrary to expectations, C10 FA20 BA showed equivalent depths to C20 FA10 BA and the same occurred for C20 FA40 BA and C40 FA20 BA regardless of the MIBA content. One the one hand, improved performance would be expected from mixes with higher FA content since the addition would lead to pozzolanic reactions capable of reducing the samples' porosity (demonstrated in the water absorption by immersion test), thereby reducing the diffusion of CO\({}_{2}\) to a greater extent than when using MIBA. On the other, it is possible that there may have been a faster reduction of overall pH in samples with higher FA content, which, in combination with the slight densification of the microstructure from the pozzolanic reaction, led to opposing effects in terms of carbonation depth.  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Indicators**} & \multicolumn{3}{c}{**EC2**} \\ \cline{2-3}  & **fad = 30\%** & **fad = 60\%** \\ \hline \multicolumn{1}{c}{Overestimated prediction (\%)} & 6.0 & 58.0 \\ \(\text{R}^{2}\) & 0.9 & 0.7 \\ \(\text{R}\) & 0.9 & 0.8 \\ \multicolumn{1}{c}{Standard error of the estimate (\(\times 10^{-6}\))} & 33.2 & 119.4 \\ \hline \hline \end{tabular}
\end{table}
Table 7: Statistical indicators of the results calculated using the EC2 model.  
Figure 9: Total length of shrinkage over 91 days (**a**) and shrinkage calculated according to the EC2 prediction model (**b**).
### Paper Contribution  
In this paper, we propose an extension of the FzGR protocol, called multi-next-hop fuzzy geographical routing (MNH-FGR). Like FzGR, the MNH-FGR protocol uses the fuzzy algorithm, but considers a limited number of neighboring nodes able to ensure a good routing of the data. The objective is to select, dynamically, a set of links with less or equal weight to a predefined threshold. This approach will make it possible to send the data packets to several neighbors instead of a single one. Our multi-next-hops approach, which respects the load balancing, aims to promote the quality of video transmission by further improving the rate of packet delivery and especially by minimizing the end-to-end delay in order to achieve a good perception from the user regarding the final content received. The main contribution of this paper can be summarized as follows: our MNH-FGR variant inherits from the FzGR protocol all the fuzzy characteristics, making it a perfect fit for vehicle-critical environments. In addition, it integrates the weighted round-robin (WRR) scheduling algorithm to balance the multiple selected links with different QoS.
## 4 Results
### Sensor Characterization
Moreover, translating the information presented in Table 2 to the sensitivity metric (i.e., voltage per single pH unit [mV/pH]), it is simple to demonstrate a measured (average) sensitivity of 57.56 [mV/pH]. Comparing this value to the Nernstian response, see Equation (3), the instrument sensitivity is 1.6 units below the reference parameter. By simple mathematical calculation this represents a 97.3% percent \"compliance\" with respect to the optimal Nernstian response. It is, thus, concluded that the proposed pH sensor characterization described in this work may enable the creation of a precise and portable instrument for global VF applications requiring pH measurements.
###### Abstract  
Vitamin D exhibits immunomodulatory effects in autoimmune diseases. We aimed to evaluate the associations of vitamin D levels with clinical and laboratory features of systemic sclerosis (SSC) in a Polish cohort. The study was prospective in design. SSc patients who met ACR-EULAR 2013 criteria underwent comprehensive clinical and laboratory investigations using the European Scleroderma Trials and Research group (EUSTAR) methodology. We assessed patients' sera for 25(OH)D3 using a radioimmunoassay, and the cutoff value for vitamin D deficiency was set at 20 ng/mL. Statistical analyses were performed using the Mann-Whitney U test, the Fisher's exact, and the Spearman's rho, where appropriate, with a significance threshold set at 0.05. We recruited 68 Ssc patients (85% female). The mean 25(OH)D3 level was 21.6 \(\pm\) 10 ng/mL, and 50% of subjects (\(n\) = 34) presented vitamin D deficiency (mean 13.7 \(\pm\) 3.9 ng/mL). Vitamin D-deficient SSc patients exhibited higher prevalence of arterial hypertension (\(p\) = 0.002), proteinuria (\(p\) = 0.002), and lung fibrosis (\(p\) = 0.032), as well as higher CRP (\(p\) = 0.035). The modified Rodnan skin score correlated negatively with 25(OH)D3 in diffuse cutaneous SSc (dcSSC). We found no correlation with the disease duration, age, joints, and the heart. Vitamin D deficiency was common in the studied population of Polish SSc patients and was associated with arterial hypertension, proteinuria, lung involvement, and increased CRP.  
vitation D; scleroderma; systemic; calcifediol +
Footnote †: journal: Applied Sciences  
1
## 1 Introduction
Converting power from the PV cell to the storage device is crucial for any energy harvesting system. There are several power converter architectures that can be used to regulate the supply voltage from the energy harvester to a suitable output voltage. Among these architectures, the low-dropout (LDO) regulator and switched-mode power supply (SMPS) systems are widely used in power management circuits [15]. LDO is a DC linear voltage regulator that is used to maintain regulation with small differences between supply and load voltage. SMPS is a type of power supply that incorporates semiconductor switching techniques rather than standard linear methods to convert the required output voltage. Moreover, in energy harvesting systems it is crucial to track the maximum power point (MPP) to maximize the harvesting efficiency. To this aim, it is necessary to use maximum power point tracking (MPPT) techniques to keep input voltage close to the operating voltage [16]. The current study is part of a broader project on wireless sensor nodes for the monitoring and logging of the soil moisture of crops. It focuses on a comparative analysis between two different power supply modules to find a suitable solution for powering wireless sensor nodes. In particular, a comparison is made between the rechargeable battery as energy reservoir and the solar energy harvesting system. The rest of this study is organized as follows. Section 2 describes the architecture of the sensor node. Section 3 presents the results and discussion of this study. Finally, conclusions are drawn in Section 4.
# A Charging and Discharging Data Privacy Protection Scheme for V2G Networks Based on Cloud-Fog-End
## 2 Problem Formalization
### Threat Model  
In this model, the connection between the TA and other entities is conducted through secure channels, while the connection to other public communication networks is not secure. According to the attack points marked in Figure 1, external adversaries may attempt to launch attacks such as eavesdropping, forgery, tampering, replay, and denial of service. Attackers may also attempt to impersonate legitimate EVs, CPs, or FNs. In this scheme, only the TA is a fully trusted entity, while the KGC is not fully trusted and may be vulnerable to malicious attacks or colluding with malicious attackers to cause a key leakage. The other entities, the CP, FN, and CSO, are honest and curious, and they honestly execute this plan, but also show curiosity about the EV's charging and discharging data or true identity.  
Therefore, we consider two attackers in the threat model, namely, the external attacker \(A_{I}\) and the internal attacker \(A_{II}\). \(A_{I}\) can query and tamper with the public key of any legitimate user but cannot obtain the master key; \(A_{II}\) represents a malicious KGC that can obtain the master key but cannot tamper with any user's public key.
## 4 Experimental Results and Discussion  
### Influence of the Key Parameters of the VFPEH on Its Output Performance  
The energy harvest effect of the VFPEH is directly related to the deformation of the piezoelectric cantilever beam, and the deformation of the piezoelectric cantilever beam is related to the mass of the end mass unit and the excited load [43; 44]. In this paper, a composite energy harvester is designed with the blunt body and both the airfoil as the mass unit of its cantilever beam. The size of the blunt body mass has an important influence on the output performance and vibration frequency of the energy harvester. The diameter of the cylindrical blunt body has an influence on the vortex forces and the frequency of the vortex vibrations [40; 43]. The diameter of the blunt body has a significant effect on the vortex force and the frequency of the vortex vibration of the energy harvester. As the diameter changes, the mass of the blunt body changes, the larger the diameter, the greater the resulting vortex excitation force; the larger the diameter of the blunt body, the lower the vortex vibration frequency. The mass of the blunt body is mainly related to the difference between its inner and outer diameter (or the size of the outer diameter if the inner diameter remains the same), i.e., its length, etc. In order not to change the size of the overall structure of the VFPEH, this paper focuses on the effect of changes in the outer diameter of the blunt body on the energy harvest effect of the VFPEH. The influence of the airfoil on the performance of the energy harvester is complex, mainly in terms of the mass of the airfoil, the area of the windward side of the airfoil, the angle between the airfoil and the incoming flow direction, etc. The optimized design and deep investigation of the VFPEH will be presented in the future work. The load resistance is an important parameter that affects the performance output of the VFPEH. As the VFPEH itself has a certain internal resistance, there is an external resistance value that maximizes the output power of the VFPEH, i.e., the optimum resistance value. In order to obtain the maximum output power of the energy harvester, it is necessary to study it.