esa-sceva/satcom-chunk-collection huggingface dataset:
# Name-Based Security for Information-Centric Networking Architectures
## 3 System Design
### The Key Escrow Problem and a DID-Based Solution  
Identity-based security schemes often suffer from the so-called key escrow problem, i.e., the fact that a third party (the SKG) knows all secret keys. Even if we assume that this party is reliable and  
Figure 2: Namespace organization for a sample file sharing application.  
does not misuse the generated secret keys, these systems still are threatened by security breaches that would reveal the _master_ key (note that this is the secret key of the SKG, used to generate all user secret keys). An obvious solution to this problem is to use multiple SKGs; each user could use the SKG they trust, or even their own. Having multiple SKGs, however, leads to another problem: How are \(PP\) disseminated? In order to solve this problem, we rely on DIDs. Our design assumes a DID registry that is not part of the ICN network; instead, entities interact with that registry using legacy networking protocols.  
This name roots are treated by our system as DIDs, and they are associated with a DID document stored in a registry. Each DID document contains the \(PP\) required for performing the corresponding IBE and IB-PRE operations (related to a content name with that root). Therefore, in order for any third party to reliably learn some \(PP\), it simply has to lookup the registry. A DID document in our system also contains a public key used for authenticating the root owner when he wants to modify the document in the registry. As we discuss in Section 5, we implemented the registry functionality using the Hyperledger Fabric blockchain technology.  
Back to our file sharing example, suppose that an entity wants to perform some cryptographic operations related to the content name \"User A/Videos/Graduation\". The root of this name is \"User A\", hence its searching of the registry for the document associated with the DID \"User A\": This document contains the desired \(PP\).  
At this point, we should note that even if per-user SKGs are used, the problem of disseminating \(PP\) is not equivalent to the problem of disseminating users' RSA public keys (as in the current Internet). This is true because even if per-user SKGs are used, the same \(PP\) may be used for generating multiple keys. The security solutions presented in the following section use content names as keys; all these keys share the same \(PP\), i.e., the \(PP\) of the content owner. Therefore, if the \(PP\) of a content owner are known, these solutions can be used without interacting with the DID registry. So, back to our file sharing example, if a user has retrieved the \(PP\) that correspond to \"User A/Videos/Graduation\", he can use them for performing cryptographic operations with the name \"User A/Videos/Holidays\".
## 4 The Dynamic Form of the Problem
### Performance with Poisson Arrivals
This indicates that our scheme achieves the _de facto_ fairness by allocating almost equal-throughput channelsfor each flow. The RR scheme can provide around 12 pps average throughput, but its minimum throughput is only around 5 pps. This is most conspicuous for the FIFO scheme where the minimum throughput is plainly zero. In fact, from the 250 pps offered load and above, HEU can provide better fairness than RR. However, it only starts to underperform in terms of average throughput after 400 pps. To sum up, when the network is not severely saturated (e.g., the offered load is four-times higher than the processing speed), our heuristic scheduling scheme for the dynamic case can provide higher average throughput across all flows. At the same time, our scheduling scheme constantly provides better fairness than other scheduling schemes. It overcomes the crowd-out effect of other scheduling schemes when the offered load is too high, and some flows may suffer for low or even zero throughput.
# Characterization of Carrier Phase-Based Positioning in Real-World Jamming Conditions
## 4 Analysis and Results
### Analysis 4: Significance of the Baseline  
The purpose of this analysis is to examine the effect of baseline length on the positioning solution. In this analysis, only dual-frequency solutions to Case 2 are considered. In order to investigate the influence of the baseline, we chose to look at GPS + Galileo solutions only, as the previous analysis showed that this solution had the best positioning accuracy. Table 7 shows the standard deviations during the jamming incident for PPK solutions on all of the baselines used in Case 2.  
Table 7 shows clearly that, even during the multifrequency jamming incident, good positioning accuracy may still be achieved with carrier phase-based positioning.  
Figures 12 and 13 provide a more in-depth look at the four PPK solutions, focusing solely on the first 25 min of the jamming incident. It is clear that all solutions are very similar, having almost entirely the same number of satellites, and (except for the very long baseline) a similar performance for the entire period.  
Figure 12: Number of satellites (**top**) and 3D positioning error (**bottom**) of the four baselines in Case 2. All solutions are based on dual-frequency GPS and Galileo data.  
Figure 13: 3D positioning error for an entire 2-h span from 17:00 to 19:00 including the jamming incident from Case 2. It is seen that the very long baseline does not manage to fully recover within this period.  
The ambiguity resolution (AR) status levels of Figure 14 are explained in [38].  
Another observation is that the sudden degradation in data when the HIP starts leads to a large positioning error for all baselines, but they quickly recover and are not that heavily affected during the rest of the HIP. This could indicate that the sudden change in jamming power has a larger effect on the positioning performance than simply having a strong steady source, leaving only a few satellites available. As discussed at the end of this paper, it would be interesting to further investigate if a moving jammer, or a jammer constantly switched on and off, would affect the PPK solutions more severely than a constant static jamming source.  
Both Figures 12 and 13 show that positioning solutions are very similar as long as the baseline is shorter than 30 km. The very long baseline actually also performs at the same level up until jamming starts, but then does not achieve the same accuracy again.  
_Summary: Baseline length shows no significant improvements in the positioning solution during jamming. Very short baselines will not provide a more robust solution, and a difference is only observed at long baselines, where positioning (i.e., ambiguity resolution) will be slightly more vulnerable to jamming._
# Effect of Calined Marble Powder and Magnetized Water on the Performance of Cement-Based Composites
###### Abstract
[25] examined the effects of MW exposed to different magnetic field durations and intensities on concrete shrinkage cracking. They determined that MW could enhance both the early-age shrinkage crack resistance and the compressive and splitting strengths of concrete. Furthermore, it was found that the length of the magnetic field exposure had a direct impact on the strength development of concrete. [PERSON] et al. [26] achieved improvements in the fresh- and hardened-state properties of cement-based composites produced with slag/fly ash and MW exposed to a 0.6 Tesla magnetic field. Recent advances, including [PERSON] et al. [24] and [PERSON] et al. [26], have investigated the role of magnetized water (MW) in enhancing the hydration process and mechanical properties of concrete. This study builds on these findings, providing a unique integration of MW and CMP, showcasing their combined benefits in cementitious composites. This study builds on such efforts by demonstrating how calcination transforms raw marble powder into a more reactive material, further improving the physical and mechanical performance. This approach aligns with Turkiye's goals of reducing waste and promoting sustainable practices. Considering the literature, it is evident that there are limited studies on the use of MW to enhance the physical and mechanical properties of cement-based composites. Furthermore, there is a lack of comparative studies between RMP and CMP as substitutes in cement-based composites. These two factors motivated the present study. While previous research has individually explored RMP or CMP, this study uniquely compares the effects of these two materials on a wide range of physical, mechanical, and microstructural properties. Although studies have independently evaluated MW or CMP, this research investigates their synergistic effects on improving hydration, workability, and mechanical performance, which has not been extensively explored before. Despite significant advancements in utilizing RMP, CMP, and MW in cement-based composites, there remains a lack of comprehensive studies examining their combined effects. This study bridges this gap by investigating the synergy between CMP and MW, alongside a direct comparison with RMP-based composites, offering novel insights into their potential for sustainable construction.
# An Unequal Clustering and Multi-Hop Routing Protocol Based on Fuzzy Logic and Q-Learning in WSNs
## 5 Results and Discussion
### Performance Evaluation in Scenario 2
#### 5.3.4 Throughput  
Figure 29 compares the network throughput of the EEUC, CHEF, and FQ-UCR protocols across networks with varying node counts, offering a clear performance evaluation of each protocol. Compared to the other protocols, FQ-UCR achieved a throughput improvement of approximately 101.8% to 151.9% under the same network conditions. The increased throughput resulted from the efficient synergy of the FL and Q-learning methods, which jointly enhanced energy efficiency and extended the network's lifespan. These elements work together to enhance FQ-UCR's efficiency in WSNs.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{
\begin{tabular}{c} **Number of** \\ **Sensor Nodes** \\ \end{tabular} } & \multirow{2}{*}{**Protocol**} & \multicolumn{2}{c}{**FND**} & \multicolumn{2}{c}{**HND**} & \multirow{2}{*}{**LND**} \\  & & **(First Node** & **(Half of Nodes’ & **(Last Node** & **Stability** \\  & & **Death)** & **Death)** & **Death)** \\ \hline \multirow{3}{*}{100 Nodes} & EEUC & 373 & 690 & 710 & 373 \\  & CHEF & 214 & 560 & 987 & 214 \\  & FQ-UCR & 1048 & 1851 & 2478 & 1048 \\ \hline \multirow{3}{*}{200 Nodes} & EEUC & 465 & 812 & 837 & 465 \\  & CHEF & 562 & 700 & 887 & 562 \\  & FQ-UCR & 1100 & 1859 & 2493 & 1100 \\ \hline \multirow{3}{*}{400 Nodes} & EEUC & 651 & 899 & 928 & 651 \\  & CHEF & 483 & 711 & 828 & 483 \\ \cline{1-1}  & FQ-UCR & 1056 & 1848 & 2501 & 1056 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Comparison of network stability period of protocols in Scenario 2.  
Figure 27: Network lifetime comparison for 400 nodes in Scenario 2.
# A Survey of OCR in Arabic Language: Applications, Techniques, and Challenges
## 3 OCR Process
### Evaluation
The proposed system uses gradient-boosted algorithms to enhance the performance; furthermore, some other classifiers are used for this purpose, i.e., \(k\)NN and Random Forest Classifier. Thus, the overall achieved accuracy is 94.53%. The authors generate the dataset during the implementation, which is available on request. The paper also provided some information on previous research in this area, where researchers used Hidden Markov Model, Support Vector Machine, and Multi-Layer perceptron classifiers. The authors also highlighted the importance of the availability of quality datasets for the improved performance of OCR techniques. The impact of OCR quality on the accuracy of short text classification tasks is presented in [108]. A multi-class classification of short text is introduced. For this, the authors propose a dataset of beauty product images that contains 27,500 entries of labeled brand data and generate results based on targeting specific brands. The authors also show that preprocessing techniques such as text normalization and noise reduction can improve the performance of the classification model on low-quality OCR text. In addition to papers improving specific processes involved in OCR, some previous papers present a combination of various OCR techniques for overall improved process accuracy. OCR4 all [109] is an open-source OCR software that combines state-of-the-art OCR components and continuous model training into a comprehensive workflow for processing historical printings and provides a user-friendly GUI and extensive configuration capabilities. The software outperforms commercial tools on moderate layouts. It achieves excellent character error rates (CER) on very complex early printed books, making it a valuable tool for non-technical users and providing an architecture allowing easy integration of newly developed tools.
###### Abstract  
Crop yield estimation is important for formulating informed regional and national food trade policies. The introduction of remote sensing in agricultural monitoring makes accurate estimation of regional crop yields possible. However, remote sensing images and crop distribution maps with coarse spatial resolution usually cause inaccuracy in yield estimation due to the existence of mixed pixels. This study aimed to estimate the annual yields of maize and sunflower in Hetao Irrigation District in North China using 30 m spatial resolution HJ-1A/1B CCD images and high accuracy multi-year crop distribution maps. The Normalized Difference Vegetation Index (NDVI) time series obtained from HJ-1A/1B CCD images was fitted with an asymmetric logistic curve to calculate daily NDVI and phenological characteristics. Eight random forest (RF) models using different predictors were developed for maize and sunflower yield estimation, respectively, where predictors of each model were a combination of NDVI series and/or phenological characteristics. We calibrated all RF models with measured crop yields at sampling points in two years (2014 and 2015), and validated the RF models with statistical yields of four counties in six years. Results showed that the optimal model for maize yield estimation was the model using NDVI series from the 120 th to the 210 th day in a year with 10 days' interval as predictors, while that for sunflower was the model using the combination of three NDVI characteristics, three phenological characteristics, and two curve parameters as predictors. The selected RF models could estimate multi-year regional crop yields accurately, with the average values of root-mean-square error and the relative error of 0.75 t/ha and 6.1% for maize, and 0.40 t/ha and 10.1% for sunflower, respectively. Moreover, the yields of maize and sunflower can be estimated fairly well with NDVI series 50 days before crop harvest, which implicated the possibility of crop yield forecast before harvest.  
Keywords:yield estimation; random forest; HJ-1A/1B; normalized difference vegetation index; Hetao Irrigation District +
Footnote †: journal: Sensors
# Channel Access in Wireless Smart Grid Networks Operating under ETSI Frame-Based Equipment Rules
###### Abstract  
Smart grid operators seeking to extend their wireless network capacity can use unlicensed bands. However, devices in these shared bands must follow rules such as Listen Before Talk (LBT), standardized by ETSI. In this paper, we focus on the performance of the frame-based equipment (FBE) version of LBT channel access. We design, implement, and validate a fully functional FBE channel access simulator. Next, we conduct an extensive performance analysis of the FBE variants encountered in the literature, focusing on channel efficiency and fairness in upper-bound and coexistence scenarios. Our study leads to several conclusions about the operation of FBE-based devices, including the need for proper configuration of channel access parameters to ensure fairness and optimal performance. We also observe generally poor coexistence among FBE variants: the highest Jain's fairness index was only 0.88, with an average normalized channel efficiency of 0.76. Therefore, we identify several open research areas in the field, such as the need for further development of parameter adaptation algorithms, the deployment of an external controller to update channel access parameters, and new FBE designs with better coexistence qualities.  
chamel access; wireless networks; Listen Before Talk; unlicensed bands Article
## 3 Research Progress on Adsorption and Separation of Hydrocarbon Molecules
### n-Alkanes
However, when the exchange is too high and exceeds 91.9%, the adsorption and desorption curve of nC\({}_{13-16}\) gradually slowed down, which is consistent with the view in the above reference that the hindering force of the long-chain alkanes is too large when the Ca\({}^{2+}\) exchange of the adsorbent is too high. Flush volume of desorption solution: The saturated adsorbent needs to be flushed with pulsed liquid to record the sample fraction, and the experiment was performed by recording every 2 mL. In summary, starting from short-chain n-alkanes (C\({}_{5-7}\)) and long-chain n-alkanes (C\({}_{10-16}\)), the researchers studied the effects of temperature, space velocity, adsorbent, water content, and Ca\({}^{2+}\) exchange degree on the adsorption and desorption performance of n-alkanes. The adsorption and desorption regular of 5A type molecular sieves on n-alkanes under different conditions were comprehensively discussed, which provides a basis for further research on the adsorption and desorption laws of n-alkanes. Figure 7: Relationship between pulse parameters of nC\({}_{10-16}\) and water content of adsorbent [36] the values of (**a**) \(\Delta V_{R}\) (**b**) \(W_{1/2}\) (**c**) \(R\). In addition to the influence of external conditions on the adsorption performance, the structure of the adsorbent itself also has an impact on the adsorption of the adsorbate. The adsorption of alkane molecules on bronsted acid sites is the key to the adsorption reaction. Therefore, it is essential to control the acidity of zeolite by regulating the Si/Al ratio. Although the adsorption selectivity is not sensitive to the Si/Al ratio, the distribution of Al plays a crucial role in the adsorption selectivity. [PERSON] [39] reported that the change in Al distribution resulted in a two-fold increase in n-hexane adsorption selectivity. When the Si/Al ratio is large, the selectivity varied greatly with the distribution of aluminum. The positions of Al atoms at different T sites have a significant effect on the overall selectivity ratio. The Al atoms can synergistically enhance the adsorption of the central C-C bond when they are close together, resulting in a higher selectivity than isolated Al atoms. Controlling the location of Al in zeolites, such as MFI and other frameworks with heterogeneous pore systems, as well as a wide range of selectivity between different T-sites, would provide the opportunity to significantly improve the specific C-C bond to alkanes Adsorption selectivity. [PERSON]. [PERSON] [40] reported the adsorption isotherms of silicalite-1 for \(\alpha\)-alkanes and diols, and explained the adsorption mechanism in depth. It can be seen that the precise regulation of the atomic sites and texture composition in the catalyst greatly affects the adsorption performance of the adsorbent.
# Dynamic Impedance Estimation: Challenges and Considerations
## 3 Harmonic Synchrophasor Estimation
### Review Harmonic Synchrophasor Estimation
For example, the MSVA algorithm generates the interpolated samples using the following difference equation [5],  
\[x[n]=D_{0}x_{0}[n]+D_{-1}x_{0}[n-1]+D_{-2}x_{0}[n-2]+D_{+1}x_{0}[n+1]+D_{+2}x_ {0}[n+2] \tag{2}\]  
where \(x[n]\) is the interpolated sample, \(x_{0}[n]\) is the crude sample, and \(D_{i},\ i=-2,-1,\ldots,2\) are time-varying coefficients given by,  
\[\left[ \begin{array}{c}D_{0}\\ D_{-1}\\ D_{-2}\\ D_{+1}\\ D_{+2}\end{array} \right]=\left[ \begin{array}{cccc}1&0&-3/4&0\\ 0&2/3&1/3&-1/6\\ 0&-1/12&1/24&1/12\\ 0&-2/3&1/3&1/6\\ 0&1/12&1/24&-1/12\end{array} \right]\cdot\left[ \begin{array}{c}1\\ \alpha\\ \alpha\\ \alpha^{2}\\ \alpha^{3}\end{array} \right] \tag{3}\]  
The time-varying coefficients are a function of \(\alpha\) that is a function of the actual frequency \(f\) (which varies with time) and the time instant \(n\). This parameter is given by,  
\[\alpha=n(\frac{f-f_{0}}{f}) \tag{4}\]  
Despite the good performance of time-domain interpolation shown in the literature, the noise interference in the resampling algorithm's quality has been almost neglected. However, there is a degradation of the estimation under adverse conditions from the analyzed methodologies, especially when the SNR is less than 60 dB. In transmission networks, SNRs greater than 50 dB are common, but 45 dB values can be observed in distribution net  
Figure 5: Block diagram of discrete Fourier transform (DFT) passed harmonic synchrophasor estimation (HSpE). works. Noise interference seems to be one of the limiting factors in estimating high-order harmonic phasors. A strategy to mitigate the effect of noise in the resampling process is using the oversampling technique [36]. Figure 6 illustrates this technique. In this case, the signal in continuous time is sampled with L times greater than the necessary. After sampling, an average moving filter (MAF) reduces the noise level, and the signal is then decimated to the required sampling frequency. It is noteworthy that some analog-to-digital converters (ADC) have this methodology as an internal function, which relieves the processor.
## 7 Conclusions
\(\boldsymbol{\Psi}|\mathcal{K}=(\boldsymbol{x}^{T},\boldsymbol{\mathbf{m}}^{T}, \boldsymbol{\mathbf{I}}^{T})^{T}\), where \(\boldsymbol{\mathbf{x}}=[x_{sk}]\) denotes the vector of stopping pattern, \(\boldsymbol{\mathbf{m}}=[m_{k}]\) denotes the vector of train formation, and \(\boldsymbol{\mathbf{I}}=[l_{k}]\) denotes the vector of train frequency for all type of trains. \(x_{sk}=1\), if \(k\in\mathcal{K}\) type trains stop at station \(s\in\mathcal{S}\), 0 otherwise. \\ \multicolumn{2}{l}{As for the stopping pattern of train \(i\in\mathcal{I}\), it can be calculated by \(x_{si}=\sum_{k\in\mathcal{K}}\tau_{ik}x_{sk},\forall s\in\mathcal{S}\) Note that the operation zone for each train type can be calculated from the stopping pattern \(\boldsymbol{\mathbf{x}}\). \\ \multicolumn{2}{l}{The train arrival order at the first station under the line planning \(\boldsymbol{\Psi}\). Based on Assumption A.4, i.e., each type of train adheres to the principle of even-headway at their origin station within a short period, the departure times of trains from their origin station can be uniquely determined by the departure frequency \(\sum_{k\in\mathcal{K}}\tau_{ik}\). \\ \(\mathcal{J}_{1}|\boldsymbol{\Psi}\) & However, the departure times at other stations are influenced by the type of each train, i.e., the decision \\ \(\boldsymbol{\Gamma}\) & The in-vehicle arc and link incidence matrix in the space-time network. \(\boldsymbol{\Gamma}=[\gamma_{\tilde{a}a}]_{|\boldsymbol{B}|\times|\mathcal{E}|}\), where \(\gamma_{\tilde{a}a}=1\), if in-vehicle arc \(\tilde{a}\in\mathcal{B}\) is the link \(a\in\mathcal{E}\), 0 otherwise. \\ \(\boldsymbol{\Phi}\) & The path-OD incidence matrix in the space-time network. \(\boldsymbol{\Phi}=[\varphi_{pw}]_{|\mathcal{P}|\times|\mathcal{W}|}\), where \(\varphi_{