esa-sceva/satcom-chunk-collection huggingface dataset:
## 5 Relationship between Cable Unstrained Length and Cable Tension
### Relationship between \(d\) and \(T_{x}\)
#### 5.2.2 Relationship between \(a_{d}\) and D  
By fixing \(\mathbf{B}^{d}\) and \(\rho\), the adjusted length \(d\) that corresponds to a certain \(T_{x}\) is obtained by optimizing (20). The relationship of \(d\) and \(T_{x}\) is modeled by using nonlinear regression with respect to (41). The result is illustrated in Figure 10 with diversity of \(D\).  
In reality, if \(D\to 0\), then \(\mathbf{B}^{d}\rightarrow\mathbf{A}\), which leads to \(T_{x}\to 0\) and \(d\in\mathbb{R}^{+}\). According to (41), the consequence of \(D\to 0\) is \(a_{d}\to 0\). That is also proven in Figure 11. Hence, the model estimated that the relationship between \(a_{d}\) and \(d\) cannot have terms that are independent of \(D\). Furthermore, if \(D\rightarrow\infty\) and \(d\) is a finite number, then \(L\to D\), which leads to \(T_{x}\rightarrow\infty\). According to (41), if \(D\rightarrow\infty\) then \(a_{d}\rightarrow\infty\). By its monotonic property, the function that expresses the relationship between \(a_{d}\) and \(D\) cannot have extrema.  
Figure 10: The relationship between \(T_{x}\) and \(d\) with different \(D\) and fixed \(\beta=0.754\) rad.  
According to these analyzes, either the power model or exponential model can be used to estimate the relationship between \(D\) and \(a_{d}\). However, the 3 rd order power model (43) is the fittest model to the collected data. In the next step, \(\beta\) will be variated with fixed \(\rho\).  
\[a_{d}=q_{a}(\beta)\cdot D^{3} \tag{43}\]  
The relationship (43) is always valid with constraint \(a_{d}\geq 0\) since \(D\geq 0\).
## 1 Introduction
The main contributions of our work can be summarized as follows:  
* The spatial distribution of the UAVs was modeled as \(\beta\)-GPP, and the UAVs were equipped with directional antennas to reduce signal self-interference. The repulsive parameter \(\beta\) describes different application environments with tunability. Different values of \(\beta\) describe the UAVs' deployment in different environments, which makes our model more practical;
* We considered the information transmission performance of a certain instantaneous snapshot. By ignoring small-scale fading of interfering links and using random geometry tools, an approximate expression for the coverage probability of multi hop relay systems was obtained, thereby obtaining the traversal capacity. Then, according to the diagonal approximate matrix property of \(\beta\)-GPP, we derived the approximate expression of the coverage probability. The above analysis results can better predict the performance of FlyMesh in different environments;
* Based on the theoretical expressions obtained, we analyzed the effects of various parameters on the performance of FlyMesh in different environments. The simulation results verified the correctness of the theoretical expression. We also adjusted the beam width _theta_ and the number of relay hops \(N\), to achieve the best network performance according to the repulsive parameter \(\beta\). The rest of this paper is organized as follows. Section 2 describes the related work. Section 3 briefly introduces the \(\beta\)-GPP related mathematics and FlyMesh system model. Section 4 gives the connection probability and ergodic capacity of multi-hop relaying, and derives an approximate expression for the coverage probability. Section 5 provides numerical results to verify the correctness of our theoretical derivation. Finally, Section 6 summarizes the work and looks forward to the application of the results.
# FD-LTDA-MAC: Full-Duplex Unsynchronised Scheduling in Linear Underwater Acoustic Chain Networks
## 4 Results and Discussion
### Percentage Reduction in Frame Duration  
The percentage reduction in frame duration across the pipeline length for both LTDA-MAC with FD nodes and FD-LTDA-MAC compared to LTDA-MAC with half-duplex nodes is shown in Figure 14. Although the monitoring rate improves across the pipeline length, the FD-LTDA-MAC shows higher percentage reduction in frame duration compared with LTDA-MAC and LTDA-MAC in FD. This is because the FD-LTDA-MAC is able to better exploit the spatial re-use. Consequently, FD-LTDA-MAC has better prospect with scalability than LTDA-MAC and LTDA-MAC in FD.
## 3 Experiment and Results  
To assess the accuracy of SBAS orbit, clock and ionospheric corrections, the SBAS message files, from 1 January 2018 to 30 June 2018, are downloaded from the CNES Navigation and Time Monitoring Facility (NTMF) FTP server ([[ftp://serenad-public.cnes.fr/SERENAD0/FROM_NTMFV2/MSG/](ftp://serenad-public.cnes.fr/SERENAD0/FROM_NTMFV2/MSG/)]([ftp://serenad-public.cnes.fr/SERENAD0/FROM_NTMFV2/MSG/](ftp://serenad-public.cnes.fr/SERENAD0/FROM_NTMFV2/MSG/))). For each SBAS system, only SBAS message files from two satellites are collected. These files are provided in the receiver independent exchange (RINEX) 2.12 type B format [41]. The SBAS satellites broadcast one message per second and thus the number of SBAS messages during the entire assessment period is expected to be 15,638,400. The missing number of SBAS messages for each satellite is counted and given in Table 1. The availability of SBAS messages varies from different SBAS satellites. The availability of PRNs 135, 138, 120, 123, 129, 137, and 127 are close to 100%. However, PRNs 128, 125 and 140 have relatively lower availability, especially PRN 125, of which the availability is 85.9%. Afterward, two sets of experiments are conducted to evaluate SBAS corrections from five different systems. Firstly, the SBAS orbit and clock corrections are evaluated with IGS final orbit and clock products as the references; Secondly, the SBAS ionospheric corrections are evaluated by comparison to the references derived from dual-frequency GNSS measurements.
## 1 Introduction
Therefore, it can be found that the multiple-band MIMO antenna in the millimeter frequency range along with the flexible configuration is a very promising factor to facilitate the high-speed wireless communication in wearable electronics. In this paper, we have designed, fabricated, and analyzed a quad-port flexible MIMO antenna operating in the mm-wave frequency range. The proposed antenna has a novel configuration with perturbed triangular-shaped radiating elements and two 'cross'-shaped slots in the ground plane. A horizontal arrangement of 1 \(\times\) 4 MIMO elements exhibits multiband characteristics. The significant diversity parameters such as envelope correlation coefficient (ECC), diversity gain (DG), mean effective gain (MEG), total active reflection coefficient (TARC), and channel capacity loss (CCL) of the MIMO antenna are calculated using CST Microwave Studio, and a prototype antenna is fabricated to compare the measured results. The manuscript is composed of nine sections, starting with the introduction followed by antenna design configuration in Section 2. In Section 3, S-parameters analysis and current distribution are performed, and Section 4 describes the realized gain, efficiency, and radiation pattern measurement. Diversity parameters are calculated in Section 5, and the bending analysis of the MIMO design is presented in Section 6. Furthermore, Section 7 presents the SAR calculation details to ensure the antenna's suitability for on-body wearable applications. Section 8 discusses the link budget analysis for verifying high data rate telemetry. The manuscript concludes with the findings presented in Section 9.
# HyperIO: A Hypervisor-Based Framework for Secure IO
## 2 Background  
### Virtualization  
Hardware-assisted virtualization [9] is a widely adopted foundation for security applications. Originally, virtualization extensions' main goals were to simplify virtual machine monitor design and improve performance. With these extensions, a virtual machine monitor, also called a \"hypervisor\", can configure the interception of various events inside the virtual machines (VMs). When an event occurs, the CPU transfers the control from the VM to the hypervisor. This transition is called a \"VM exit\". In addition, the CPU stores the information about the occurred event in a data structure for the hypervisor's latest inspection.  
The hypervisor manages the memory of the VMs through a secondary-level address translation (SLAT) mechanism called \"extended page tables\" (EPT) by Intel. The hypervisor can define a page table for each VM, representing translation and access rights of the VM's physical addresses to real physical addresses. Using EPT, the hypervisor can isolate itself and the VMs from each other.  
A hypervisor can intercept a wide range of events, while interception of some events, e.g., access to IO ports, can be disabled, others, e.g., execution of the CPUID instruction, induce VM exits unconditionally. We handle three types of events: (1) access to IO ports, (2) execution of the CPUID instruction, and (3) EPT violations. HyperIO and other hypervisors use the CPUID instruction as a hypercall instruction. The interception of access to IO ports and memory regions protects the sensitive IO and hypervisor.
## 5 Conclusions  
This paper presents a joint method based on the Hough transform of RSPWVD to detect time-varying interferences with crossed frequency for GNSS receivers with a single antenna. The analytical expression of initial frequency estimation and chirp rate estimation is presented and the double threshold detection is proposed as well.  
The performance of the developed method has been assessed by experiments under conditions where the real BDS B1I signals corrupted by the simulated chirp interferences are collected by the GNSS software receiver. The actual performance of experiments has been shown by the quantitative metric RMSE of the parameter estimation. In addition, the effect of the sweep period on the estimation of the initial frequency and chirp rate has been analyzed.  
The ROC curves have been used to assess the performance of the notch filter to mitigate chirp interference by Monte Carlo simulations. The results depict that the proposed method can effectively detect and identify the chirp interferences with crossed frequency and provide the same root mean square errors (RMSE) of the parameter estimation for chirp one and the improved initial frequency estimation for chirp two compared with the Hough transform of WVD when JNR equals or surpasses 4 dB. Furthermore, the RSPWVD method itself can provide better performance in reducing cross-term interference and needs less computational requirements compared with the WVD method.  
[PERSON] contributed to design the algorithms, performed the experiment, analyzed the results of the experiments and wrote this paper. [PERSON] provided valuable feedback and advice during the manuscript modification.  
This research received no external funding.  
The authors declare no conflict of interest.
###### Abstract  
The aim of this study was to determine the gait features that are most suitable for the quantified assessment of the severity of Parkinson's disease (PD). This study computed the mean and variance of the four phases of gait intervals, i.e., stride, swing, stance and double-support intervals, and lateral difference to determine the difference between three groups, i.e., control subjects and PD patients with two severity levels (early and advanced stage) of the disease, PD1 and PD2. Data from 31 subjects were used in the study. The data were obtained from the public database (16 control healthy subjects, 6 Parkinson's disease patients with early stages, and 9 Parkinson's disease patients with advanced stages based on the Hoehn and Yahr scale). The main outcome measure of the study was the group difference of the four gait interval parameters and the statistical significance of this difference. The results show that there was a significant increase in the variance of the four gait intervals with the severity of the disease. However, there was no significant difference in the mean values between the three groups. It was also observed that the fraction corresponding to the double-support interval was significantly higher for PD patients. This study has shown that the variance of the gait parameters and the fraction of double-support interval are associated with the severity of PD and may be suitable measures for a quantified evaluation of the disease.  
Keywords: gait; double support; Parkinson's disease; variance; lateral differences +
Footnote †: journal: Applied Sciences
# Genetic Algorithm-Based Model Updating in a Real-Time Digital Twin for Steel Bridge Monitoring
###### Abstract  
The integration of digital twin technology with structural health monitoring (SHM) is revolutionizing the assessment and maintenance of critical infrastructure, particularly bridges. Digital twins--virtual, data-driven replicas of physical structures--enable real-time monitoring by continuously synchronizing sensor data with computational models. This study presents the development of a real-time digital twin for a three-span steel railway bridge, utilizing a high-fidelity finite element (FE) model built using OpenSeesPy v 3.5 and instrumented with 18 strategically placed accelerometers. The dynamic properties of the bridge are extracted using Stochastic Subspace Identification (SSI), enabling an accurate estimation of modal parameters. To enhance the fidelity of the digital twin, a genetic algorithm-based model-updating strategy is implemented, optimizing the steel elastic modulus to minimize discrepancies between measured and simulated frequencies and mode shapes. The results demonstrate a remarkable reduction in frequency errors (below 5%) and a significant improvement in modal shape correlation (MAC > 0.93 post-calibration), confirming the model's ability to reflect the bridge's true condition. This work underscores the potential of digital twins in predictive maintenance, early damage detection, and life-cycle management of bridge infrastructure, offering a scalable framework for real-time SHM in complex structural systems.  
digital twin; structural health monitoring (SHM); genetic algorithms; real-time monitoring; sensor data integration; model updating [PERSON]  
[PERSON], [PERSON], [PERSON] Genetic Algorithm-Based Model Updating in a Real-Time Digital Twin for Steel Bridge Monitoring. _Appl. Sci._**2025**, 15, 4074. [[https://doi.org/10.3390/appl5084074](https://doi.org/10.3390/appl5084074)]([https://doi.org/10.3390/appl5084074](https://doi.org/10.3390/appl5084074))
###### Abstract  
Classification, segmentation, and recognition techniques based on deep-learning algorithms are used for smart farming. It is an important and challenging task to reduce the time, burden, and cost of annotation procedures for collected datasets from fields and crops that are changing in a wide variety of ways according to growing, weather patterns, and seasons. This study was conducted to generate crop image datasets for semantic segmentation based on an image style transfer using generative adversarial networks (GANs). To assess data-augmented performance and calculation burdens, our proposed framework comprises contrastive unpaired translation (CUT) for a conditional GAN, pix2 pixHD for an unconditional GAN, and DeepLabV3+ for semantic segmentation. Using these networks, the proposed framework provides not only image generation for data augmentation, but also automatic labeling based on distinctive feature learning among domains. The Frechet inception distance (FID) and mean intersection over union (mIoU) were used, respectively, as evaluation metrics for GANs and semantic segmentation. We used a public benchmark dataset and two original benchmark datasets to evaluate our framework of four image-augmentation types compared with the baseline without using GANs. The experimentally obtained results showed the efficacy of using augmented images, which we evaluated using FID and mIoU. The mIoU scores for the public benchmark dataset improved by 0.03 for the training subset, while remaining similar on the test subset. For the first original benchmark dataset, the mIoU scores improved by 0.01 for the test subset, while they dropped by 0.03 for the training subset. Finally, the mIoU scores for the second original benchmark dataset improved by 0.18 for the training subset and 0.03 for the test subset.  
annotation; semantic segmentation; smart farming; GAN; FID; IoU; CUT; pix2 pixHD; DeepLabV3+ +
## 2 Data and Methods
### TSIS-1 Data  
In the atmospheric RT model, we use the Total and Spectral Solar Irradiance Sensor (TSIS-1) Hybrid Solar Reference Spectrum (HSRS) [23]. We smoothed the 0.1 nm spectral resolution TSIS-1 HSRS spectrum with a 5 nm boxcar rolling filter to create a proxy of the OCI extraterrestrial solar irradiance (ETS) (Figure 1). At wavelengths below 2400 nm, the original TSIS-1 HSRS hybrid spectrum was constructed by adjusting the absolute irradiance scale of high spectral resolution solar irradiance datasets with measurements from the Spectral Irradiance Monitor (SIM) on the TSIS-1 mission aboard the International Space Station (ISS). The TSIS-1 SIM instrument is a prism-CCD spectrometer with SI-traceable calibration monitored carefully on-orbit [24]. The uncertainties reported for the TSIS-1 HSRS are 1.3% in the UV region used in this study. Daily TSIS-1 SIM measurements from one week in early December 2019 when solar activity was near minimum were used to construct the reference spectrum. The TSIS-1 HSRS spectrum is recommended by the PACE science team for the use in OCI L2 algorithms. We corrected TSIS-1 HSRS, reported at a standard distance of 1 AU, for the variation of ETS with the Sun-Earth distance (\(\pm\)3.5%).  
Figure 1a shows TSIS-1 high spectral resolution extraterrestrial solar irradiance measurements at varying boxcar smoothing widths from 1 to 5 nm (OCI 5 nm resolution in dark red). The spectral shape was chosen because OCI data will be collected at a higher resolution in orbit and averaged onboard to 5 nm resolution. Figure 1b shows spectral details in the UV-A region. The high-frequency structure in the irradiance spectra results from solar Fraunhofer features, resulting from absorption in the Sun's photosphere. The depth of the prominent Ca H and K Fraunhofer lines at 396.847 and 393.366 nm diminishes rapidly as smoothing is applied, and a notable distortion and spectral shift in the Fraunhofer features occurs as the smoothing width is increased from 3 to 5 nm.
## 2 Results and Discussion
### Qualitative Characteristics of Fruit  
#### 2.4.1 Fruit Composition  
Biorfortification with selenium, both at FL and IG, affected the compositional traits of fruit collected at the red-ripe stage. In the fruit of the first truss, Se enrichment decreased titratable acidity and increased dry weight compared to the control (Table 5), while SSC (soluble solid content) and maturity index were not affected. In the fruit of the second truss (Table 6), dry weight and titratable acidity showed the same effects as Se-enrichment, as observed in the first truss, whereas SSC increased. Thus, the maturity index was significantly affected by Se-enrichment.  
The taste index, based on brix and titratable values, slightly decreased in fruit treated with 1.5 mg Se L\({}^{-1}\) of both protocols and in fruit treated with 1 mg Se L\({}^{-1}\) at the IG stage. Considering that a taste index of \(<\)0.7 is associated with low quality [32], plants treated with selenium selenate produced tastely fruit. These results on fruit composition agree with previous studies conducted by our research group [18; 20] in which tomato plants grown in hydroponics were enriched with the same concentration of Se, as sodium selenate, which was added to the nutrient solution.
# Gap Analysis of Ambient Electromagnetic Noise Measurements Stored in the ITU Data Banks
## 6 Conclusions  
### RNDB Data Set Should Not Be Used for an Empirical Model  
As was shown, blindly combining measurements and ignoring that these data sets were obtained in different countries, in different environments, on dissimilar frequencies, and in different years, is not a good idea. This will introduce a strong bias towards certain countries for subsets of the model, and result in an inconsistent model that does not represent reality. Furthermore, it was noted that all measurements come from rich and industrialized countries. Data from large parts of the globe, especially from LMIC countries, are missing. This makes it impossible to create an empirical new model that represents all countries based on these measurements.
## 3 Results
### Spectral Vegetation Indices
Distinct differences between glyphosate application and the other treatments became obvious on day 4. From then on, vegetation dieback progressed rapidly. On day 16 and day 23, the glyphosate and drought treatment looked alike just as it was observed with the SVC reflectance data. Using image data, however, spatial patterns caused by the different development or dieback of the plants are additionally revealed. Finally, CRI-1 based on hyperspectral image data revealed differences in the health status of plants at the beginning of the experiment which were not visible to the naked eye. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \multirow{2}{*}{**Spectral Index**} & \multirow{2}{*}{\begin{tabular}{c} **Dry Matter** \\ **(\%)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Chlorophyll _ab_** \\ **(mg/g DM)** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **Carotenoids** \\ **(mg/g DM)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **Polyphenols** \\ **(mg/g DM)** \\ \end{tabular} } \\ \hline  & \(R^{2}\) & **Sig.** & \(R^{2}\) & **Sig.** & \(R^{2}\) & **Sig.** & \(R^{2}\) & **Sig.** \\ \hline PSSRa & 0.55 & *** & 0.80 & *** & 0.79 & *** & 0.31 & *** \\ \hline IRECI & 0.56 & *** & 0.71 & *** & 0.72 & *** & 0.28 & *** \\ \hline mARI & 0.46 & *** & 0.63 & *** & 0.62 & *** & 0.32 & *** \\ \hline CRI-1 & 0.63 & *** & 0.87 & *** & 0.86 & *** & 0.31 & *** \\ \hline PRI & 0.86 & *** & 0.85 & *** & 0.87 & *** & 0.22 & *** \\ \hline NDLI & 0.91 & *** & 0.79 & *** & 0.82 & *** & 0.15 & *** \\ \hline NDVI & 0.93 & *** & 0.78 & *** & 0.82 & *** & 0.16 & *** \\ \hline NDWI & 0.88 & *** & 0.72 & *** & 0.75 & *** & 0.19 & *** \\ \hline \end{tabular}  
* Sig. = Significance code; *** \(p<0.001\).  
\end{table} 
Table 5: Coefficient of determination (\(R^{2}\)) and significance level (Sig.) between the chemical parameters and the spectral vegetation indices (\(n=99\)).
## 4 The Design of Routing Protocol  
In this section, an elaborate outline of the devised routing protocol design is presented, including the packet structure, the exchange of node status knowledge, and the forwarding of data packets.