esa-sceva/satcom-chunk-collection huggingface dataset:
## 1 Introduction
Enough experiences from field testing have implied that, as much as possible precise controllability is essentially demanded during implementing or operating heat extraction from HDR. Closed-loop geothermal systems (CLGSs) also become an essential approach in developing geothermal energy from deep, including dry rocks. Numerous closed-loop configurations have been proposed, mainly including coaxial closed-loop geothermal systems and U-tube systems [17; 18]. During the heat extraction process, fluid circulation is looping convection inside the borehole closure, transporting heat exchanged from the wellbore inward wall by its conduction radially through the external wall from the contacted surrounding rocks. Since the flow rate of injection fluid inside closure tubes has been facilitated for flexible adjustment, the two-level heat exchange not only relies on the formation of original permeability and stimulation effect of hydraulic fracturing. Hence, the controllability during heat production is substantially improved than that during conventional EGS with regard to HDR. As well, instability hazards such as induced earthquakes are effectively avoided. In 2019, near Sylvan Lake, Alberta, Canada, Eavor established a full-scale demonstration project by adopting CLGSs. With a bottom-hole temperature of 78 \({}^{\circ}\)C and well depth of approximately 2400 m, about 800 kw/h was achieved as thermal output [19]. However, as CLGSs collect heat energy mainly along radial heat conduction, a crucial challenge becomes how to revise the minute heat conductivity of surrounding rocks and provide sufficient contacting areas of the heat exchange interface between fluid and solid [20; 21]. In conclusion, it is hardly expectable to satisfy the scale of power generation by exploiting HDR only by adopting either conventional EGS or cutting-edged CLGSs. Therefore, in terms of fundamental schemes for the sake of large-scale deep geothermal exploitation, an innovative breakthrough looks urgently needed. Aiming at a solution to the bottleneck existing in EGS and CLGSs, a novel scheme is proposed in this paper turning geothermal energy extraction using dominant techniques from petroleum over to mineral mining, i.e., an extensive study on Excavation based Enhanced Geothermal System (EGS-E), to contribute to realizing extremely large-scale heat production from HDR. In addition, to introduce the essence inside this EGS-E, the representative heat exchange mechanism with regard to a core engineering unit is analyzed through numerical simulation. In addition, its intrinsic advantages, as well as scientific and technical challenges being brought about, are discussed.
# Mapping [PERSON] Using Sentinel-1 SAR Time Series in Camargue, France
## 3 Methodology
### Temporal Behavior of \(\sigma^{\circ}\) SAR Backscattering over Agricultural Plots
#### 3.1.2 VV/VH Signal Variance  
Variance is the expectation of the squared deviation of a random variable from its mean. Informally, it measures how far a set of numbers is spread out from their average value. It is expected that the variance values for VV/VH in rice plots are higher than other crop types, since the values change rapidly during the growing season. For example, Figure 4 shows a slight variation of VV/VH for vineyards, grasslands, and swamps during the period between May and September, whereas an important variation of the VV/VH signal is observed for the rice plots. For this reason, the variance value of  
Figure 6: Gaussian fitting of the VV/VH temporal series for a rice plot with the corresponding fitting parameters. Raw normalized data in black, smoothed data in blue and Gaussian fitted data in red.  
VV/VH was calculated for each parcel and is considered to be an additional metric for classifying rice plots.
# Multi-User Linear Equalizer and Precoder Scheme for Hybrid Sub-Connected Wideband Systems
###### Abstract  
Millimeter waves and massive multiple-input multiple output (MIMO) are two promising key technologies to achieve the high demands of data rate for the future mobile communication generation. Due to hardware limitations, these systems employ hybrid analog-digital architectures. Nonetheless, most of the works developed for hybrid architectures focus on narrowband channels, and it is expected that millimeter waves be wideband. Moreover, it is more feasible to have a sub-connected architecture than a fully connected one, due to the hardware constraints. Therefore, the aim of this paper is to design a sub-connected hybrid analog-digital multi-user linear equalizer combined with an analog precoder to efficiently remove the multi-user interference. We consider low complexity user terminals employing pure analog precoders, computed with the knowledge of a quantized version of the average angles of departure of each cluster. At the base station, the hybrid multi-user linear equalizer is optimized by using the bit-error-rate (BER) as a metric over all the subcarriers. The analog domain hardware constraints, together with the assumption of a flat analog equalizer over the subcarriers, considerably increase the complexity of the corresponding optimization problem. To simplify the problem at hand, the merit function is first upper bounded, and by leveraging the specific properties of the resulting problem, we show that the analog equalizer may be computed iteratively over the radio frequency (RF) chains by assigning the users in an interleaved fashion to the RF chains. The proposed hybrid sub-connected scheme is compared with a fully connected counterpart.  
massive MIMO; millimeter wave communications; analog precoder; hybrid analog-digital multi-user equalizer; sub-connected architectures +
Footnote †: journal: Electronics
## 2 Disturbance Torque Model of the Sun-Tracking Solar Array
### Friction Torque Model  
Upon analyzing the SADA structure, the internal friction torque of the SADA is found to mainly consist of bearing friction, harmonic reducer friction, and conductive slip ring friction. Bearing friction is relatively small, so its influence is ignored in this paper.  
Due to its structural characteristics, the harmonic reducer has nonlinear friction in the transmission process [24]. The static Stribeck model, which is suitable for simulating the influence of low-speed mechanical friction, can be used to describe the relationship between the nonlinear friction and angular velocity of the harmonic reducer, and the friction torque can be expressed as [25]:  
\[T_{f,h}=\left\{T_{c}+(T_{s}-T_{c})\exp\!\left(-|\omega_{l}/\omega_{s}|^{\delta }\right)+\sigma\cdot|\omega_{l}|\right\} \tag{5}\]where \(T_{c}\) is the Coulomb friction moment, \(T_{s}\) is the Stribeck friction moment, \(\omega_{l}\) is the rotation angular velocity of the solar array along the drive axis direction, \(\omega_{s}\) is the Stribeck velocity, \(\delta\) is the Stribeck shape factor, and \(\sigma\) is the viscous friction factor. In this paper, the Tustin empirical model is used to describe the Stribeck phenomenon, so \(\delta=1\).  
The friction moment of the conductive slip ring is mainly caused by the friction pair between the ring and the brush, and its calculation formula is:  
\[T_{f,c}=N_{c}p\mu r \tag{6}\]  
where \(N_{c}\) is the number of contact pairs of the ring and brushes, \(p\) is the single point pressure, \(\mu\) is friction coefficient, \(r\) is the radius of the conducting ring.  
In conclusion, the internal friction torque of the SADA can be obtained as follows:  
\[T_{f}=T_{f,h}+T_{f,c}=\Big{\{}T_{c}+(T_{s}-T_{c})\exp\Bigl{(}-|\omega_{l}/ \omega_{s}|^{\delta}\Bigr{)}+\sigma\cdot|\omega_{l}|\Big{\}}+Np\mu r \tag{7}\]
## 2 Results and Discussion
### Molecular Mass and Amino Acid Sequences of the Purified Peptides  
The properties of peptides are related to their composition, structure, MW, amino acid sequence and hydrophobicity. Considering the radical-scavenging ability, the amino acid sequences and molecular mass of the three isolated peptides were analyzed using a protein sequencer and quadrupole-time of flight mass spectrometry (Q-TOF MS), respectively. The mass spectra of the three isolated peptides were shown in Figure 5. The amino acid sequences of SCPE-A, SCPE-B and SCPE-C were identified as Gly-Pro-Glu (GPE), Gly-Ala-Arg-Gly-Pro-Gln (GARGPQ), and Gly-Phe-Thr-Gly-Pro-Pro-Gly-Phe-Asn-Gly (GFGPPFNG), with molecular masses of 301.30 Da,  
Figure 4: RP-HPLC profile of Fr.4-1 on a Zorbax C18 column with a linear gradient of acetonitrile (0%–50% for 32 min) containing 0.1% trifluoroacetic acid (TFA) at a flow rate of 0.8 mL/min.  
Figure 3: Elution profile of Fr.4 in Sephadex G-15 chromatography (**A**) and HO\(\bullet\) scavenging activity of Fr.4 and its fractions at 5 mg protein/mL (**B**). All data are presented as the mean \(\pm\) SD of triplicate results. \({}^{a<}\) Values with same letters indicate no significant difference for each group of samples at the same concentration (\(p>0.05\)).  
584.64 Da and 950.03 Da, respectively, which were in agreement with the theoretical masses of 301.27 Da, 584.64 Da, and 949.12 Da, respectively.
## 4 Experimental Results
### Calibration and Human-in-the-Loop Evaluation  
Expected Calibration Error (ECE) scores (Table 4) reveal that XCeption and VGG16 are better calibrated compared to ResNet-50.  
A human-in-the-loop assessment (Table 5) shows that manual verification can significantly reduce misclassification errors.  
\begin{table}
\begin{tabular}{l c c} \hline \hline
**Model** & **ECE (\%)** & **Calibration Quality** \\ \hline XCeption & 4.6 & Well-Calibrated \\ VGG16 & 4.1 & Well-Calibrated \\ ResNet-50 & 9.3 & Poorly-Calibrated \\ \hline \hline \end{tabular}
\end{table}
Table 4: Expected Calibration Error (ECE) scores of the models on DFDC.  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Model** & **No Distortion** & **H.264 (1 Mbps)** & **Gaussian Blur** & **Gaussian Noise** \\ \hline XCeption & 89.2 & 87.1 & 83.5 & 84.8 \\ ResNet-50 & 72.8 & 71.3 & 66.1 & 68.0 \\ VGG16 & 85.5 & 84.2 & 80.7 & 81.9 \\ MobileNet V2 & 80.2 & 78.6 & 75.2 & 76.5 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Accuracy under common distortions (DFDC).  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Model** & **Clean Acc.** & **Adversarial Acc.** & **AUC-ROC (Adv)** \\ \hline XCeption & 89.2\% & 79.1\% & 0.85 \\ ResNet-50 & 72.8\% & 64.2\% & 0.67 \\ VGG16 & 85.5\% & 74.3\% & 0.78 \\ MobileNet V2 & 80.2\% & 69.4\% & 0.74 \\ \hline \hline \end{tabular}
\end{table}
Table 3: FGSM attack results (\(\epsilon=0.01\)) on DFDC.  
\begin{table}
\begin{tabular}{l c c} \hline \hline
**Model** & **ECE (\%)** & **Calibration Quality** \\ \hline XCeption & 4.6 & Well-Calibrated \\ VGG16 & 4.1 & Well-Calibrated \\ ResNet-50 & 9.3 & Poorly-Calibrated \\ \hline \hline \end{tabular}
\end{table}
Table 4: Expected Calibration Error (ECE) scores of the models on DFDC.
## 4 Conclusions  
In this work, the possibility to separate ALA from a binary protein mixture of proteins having similar MW (when present as monomers) and charge by charged UF process was demonstrated. Compared to current literature, here, the UF process was carried out far from the isoelectric point of both proteins and in conditions where they both bore the same charge as the membrane. This was performed in order to limit fouling and to achieve ALA separation on the basis of electrostatic repulsion, Donnan exclusion, and size exclusion.  
\begin{table}
\begin{tabular}{c c c} \hline
**Initial Binary Protein Mixture** & **ALA Recovery Factor (\%)** & **ALA Purity (\%)** \\
**Concentration (mg/mL)** & & \\ \hline
0.5 & 33 & \\ \hline
1.0 & 32 & 95 \\ \hline
2.0 & 33 & \\ \hline \end{tabular}
\end{table}
Table 3: ALA recovery factor and purity in the permeate as a function of initial protein mixture concentration and constant flux during UF carried out at pH 3.4.  
The work identified the operating conditions leading to high recovery factor and protein purity in the absence of irreversible fouling. When the ultrafiltration of the binary protein mixture was carried out at pH 3.4, and with initial protein concentration of 1 g:L\({}^{-1}\), a fractionation of ALA with respect to BLG was obtained with a recovery factor of about 80% and a purity of 95%. The pure water permeance of the membrane was fully recovered after protein separation by simply rinsing the membrane with buffer solution. Measurements of hydraulic resistance confirmed that reduction of flux with increasing of VRF was due to reversible fouling. Even though, in the presence of real whey, antifouling properties might change due to the presence of proteins with different charge, this study provides a solution tuned for protein pairs after their easy separation from larger/smaller proteins that differ by at least a factor of 10 in terms of molecular weight.  
The following are available online at [[https://www.mdpi.com/article/10](https://www.mdpi.com/article/10)]([https://www.mdpi.com/article/10](https://www.mdpi.com/article/10)) 3390/app11199167/s1, Figure S1: Zeta potential measurement as a function of pH of ALA and BLG (1 g:L\({}^{-1}\)). Figure S2: SDS-page carried out on final retentate (4.4 h) after UF by using binary protein mixture (1 g:L\({}^{-1}\)) pH 3.4 and charged regenerated cellulose membrane. 1: IS (1 g:L\({}^{-1}\)); 2: internal MW standard; 3: retentate obtained n the UF process after 4.4 h.  
R.M.: conceptualization, performing experiments, data curation, writing, review and editing; A.M.S.: performing experiments, data curation; E.D., M.A.-F. and M.A.A.: funding review and editing; L.G.: funding, writing, review, and editing. All authors have read and agreed to the published version of the manuscript.  
This work was financially supported by the project \"Membrane systems in regenerative medicine, tissue engineering, and biotechnology\" AGREEMENT No. KACST-ITM-CNR/03.  
Not applicable.  
The authors declare no conflict of interest.
# A Survey on Cybersecurity in IoT
## 4 Network Security and Communication Protocols
### Security Challenges in IoT Protocols
Z-Wave, a low-power communication protocol often used in home automation systems, faces threats such as DoS attacks and encryption key compromise. Strengthening Z-Wave networks requires improved key management systems, regular firmware updates, and the integration of advanced encryption protocols [175; 176]. LoRaWAN, a protocol for long-range, low-power IoT communication, is commonly used in smart agriculture, logistics, and urban infrastructure. It faces challenges like session key distribution vulnerabilities and replay attacks. Adopting end-to-end encryption and secure key provisioning methods can help secure LoRaWAN-based systems [177; 178]. Thread, an IPv6-based low-power protocol for connected devices, offers strong security through its mesh networking capabilities. However, effective key management remains critical to preventing unauthorized network access and data breaches [179; 180]. Wi-Fi, while ubiquitous in IoT applications, has its own vulnerabilities, such as susceptibility to key reinstallation attacks (e.g., KRACK) and weak password policies. Advanced security protocols like Wi-Fi Protected Access 3 (WPA3) provide enhanced encryption and authentication mechanisms, addressing many traditional Wi-Fi security issues [181; 182].
## 3 ADDT Analysis
### Failure-Time Analysis
As described in the table, the overall lifetimes based on the closed-form equation become conservative since this method does not consider the variability of the parameters and directly estimates the constant value of the independent parameter set, \(\hat{\theta}\equiv\left(\hat{\beta},\ \hat{E}_{a}\right)\). On the other hand, the numerical method provides a more centralized lifetime distribution, where the generated degradation paths are spread around the original path through the closed-form equation. Figure 11: Simulated degradation paths and failure-time distribution at normal use conditions from the ADDT data. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \begin{tabular}{c} **Estimation** \\ **Method** \\ \end{tabular} & **Percentile** & **1** & **5** & **10** & **20** & **30** & **40** & **50** \\ \hline \multirow{2}{*}{\
\begin{tabular}{c} Closed-form \\ equation \\ \end{tabular} } & Hour & 4,694 & 14,256 & 25,925 & 53,775 & 91,351 & 144,033 & 220,914 \\  & (Year) & (3.22) & (9.76) & (17.76) & (36.83) & (62.57) & (98.65) & (151.31) \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Monte Carlo \\ simulation \\ \end{tabular} } & Hour & 18,061 & 29,356 & 38,593 & 94,050 & 127,629 & 168,546 & 220,311 \\  & (Year) & (12.37) & (20.11) & (26.43) & (64.42) & (87.42) & (115.44) & (150.90) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Percentile estimation of the return-spring at normal use conditions.
# Evaluation of a Framework for Robust Image Reversible Watermarking
## 2 Evaluation of the Robust Framework for Robust Reversible Image Watermarking
### Description of the Framework  
In [20], a framework is proposed to construct a robust reversible watermarking scheme with signal restoration. Figure 1 shows the framework, which consists of two processes: encoding and decoding. Each process consists of a fragile stage and a self-recovery stage. Figure 2 shows a general fragile reversible watermarking scheme. Secret message \(M\) is hidden in a host signal \(X\), resulting in a watermarked signal \(Y\) transmitted through a noise-free channel. The extraction process requires \(Y\) and control data to reconstruct the host signal \(X\), and it also recovers a message \(M^{\prime}\).  
On the other hand, Figure 3 shows a general self-recovery scheme that can detect tampered regions and reconstruct them with the embedded control data.  
In the encoding process, the fragile embedding stage inserts the secret message \(m\) into the host signal \(x\), producing a watermarked signal \(y\). Then, the self-recovery stage embeds control information, which allows the recovery of the signal after a content replacement attack. The result is the protected signal \(y^{\prime}\).  
In the presence of a content replacement, attack signal \(y^{\prime}\) becomes an attacked signal \(\hat{y}\). The decoding process receives \(\hat{y}\), then the restoration stage tries to revert the attack. The self-recovery restoration stage extracts the control information embedded in the encoding process and utilizes it along with the remaining non-attacked regions of the signal to restore the regions altered by the attack. If the attack is limited to a threshold, the watermarked signal \(y\) produced by the encoding process is obtained. From the watermarked signal \(y\), the fragile RWS extraction and recovery stage can extract the secret message and recover the original samples from the host signal.
# Tunable RF Filters Based on Liquid Crystal for Space Applications
## 1 Introduction
Other resonator modes may be found that are equally suitable for this purpose. The geometry and distribution of the electrical field inside the circular shaped resonator are shown in Figure 1. The field pattern was calculated by means of the software tool Ansys HFSS (Ansys, Electromagnetics Suite 15.0, Canonsburg, USA), which performs full-wave simulation by employing a finite-element approach. The electrical field is oriented from the bottom to the top, with its maximum in the center and vanishing field along the lateral housing wall. Figure 1: Circular-shaped cavity and electrical field lines of the TM010 mode, three-dimensional (3D) view from a simulation tool. A photograph of a practical realization of this resonator is shown in Figure 2. With respect to Figure 1, the z-axis is now oriented towards the observer. The resonator cavity is milled out of aluminum, which is silver-plated to improve RF loss performance. The upper enclosure of the resonator is a planar lid (also made of silver-plated aluminum), screwed onto the resonator housing using four screws. The liquid crystal container is reaching into the cavity from the right side. Thus, the liquid crystal material is placed in the center of the cavity, where the highest electrical field is present and hence, the maximum tuning effect can be achieved. The liquid crystal container penetrates the cavity through a hole in the lateral wall. This hole can be regarded as a circular waveguide, and since its diameter is much smaller than the wavelength in the Ka-band, it can be understood that the flow of RF energy through this hole can be easily controlled by its length. At the bottom of the cavity, partly hidden by the upper edge of the lateral wall in Figure 2, a coaxial connector is entering the resonator. It is used to determine the resonance frequency of the resonator by measurement. The liquid crystal container is made from Rexolite. This material is a cross-linked polystyrene and has favorable properties for the current application, namely low RF losses, low dielectric constant (as not to dominate the resonant frequency), it can be machined easily, and further, it is commonly used in space applications [7]. The resonator cavity inside the metal housing has a diameter of 15.5 mm and a height of 3.8 mm. With a liquid crystal container having a diameter of the liquid crystal volume of 1.5 mm, the resonance frequency was tuned from 18,707 MHz to 18,836 MHz, by changing the orientation of the liquid crystal with external permanent magnets.
## 4 Discussion
On the other hand, PP was the material with the lowest migration of phthalates. PP is a linear hydrocarbon polymer that can have an isotactic, syndiotactic and atactic structure. It is widely used thanks to its good physical and chemical properties that can be adjusted by adding different types of additives. PP may contain phthalates such as DBP, DEHP and DIBP, primarily due to the presence of catalysts [33]. DEHP is the most commonly found phthalate ester in foods [34]. In this study, the levels of DEHP in carp, which has a lipid content of 5.2%, are, in most of the samples, statistically significantly different (\(p\leq 0.05\)) from the meat of trout and salmon, which have higher percentages of fat and reached 9.5% and 11.4%, respectively. That correlation was most visible with LDPE and PAPE packaging after 6 months of storage (Figure 3). In the meat of carp packed in LDPE that contained a lower percentage of fat, the concentration of DEHP was 159.34 ug/kg; in trout, was 191.59 ug/kg; and in the meat of salmon, was 213.01 ug/kg. In the samples packaged in PAPE, the DEHP level in carp meat reached 182.36 ug/kg, and in trout, it was 198.62 ug/kg, while, in salmon, as the fattiest fish, it reached 253.56 ug/kg. Since phthalate esters are lipid-soluble, it was expected that a higher amount of DEHP migrated in fish with a higher fat content. With DIBP and DBP, it was more difficult to see a correlation between the fat content and phthalate levels, possibly because the values of these phthalates were lower than the DEHP values. The presented values show that the migration of DBP and DEHP from the examined plastic packagings did not exceed the levels in accordance with the EC [12], which regulates the migration of some phthalates from food contact material to food and which the maximum levels are 0.3 mg/kg for DBP and 1.5 mg/kg for DEHP. The concentrations obtained in this study are far below, which indicates that the plastic materials used for the packaging and storing of smoked fish at a temperature of \(-18~{}^{\circ}\)C are safe regarding the migration of the tested phthalates. We acknowledge the levels of these contaminants should be monitored, and research in this field should be continued, especially since there are no legal restrictions regarding the maximum level of phthalates in food.