esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Attack Surface Analysis
### Radio Access Control
#### 4.1.2 Formal Model for Attack Scaling
The following table illustrates the estimated time needed for brute-force attacks on passwords using various hardware configurations: an Intel i7 CPU, an NVIDIA GeForce RTX 3070 GPU, and an NVIDIA Quadro RTX A6000 GPU. The data highlight the increasing challenge of brute-force attacks with longer passwords and demonstrate the significant influence of hardware acceleration, particularly evident in the marked reduction in attack times when utilizing powerful GPUs. This insight proves crucial in assessing password resilience against brute-force attacks and emphasizes the importance of implementing robust password security measures. Specifically, tests revealed that the i7 node can attempt approximately 33,000 passwords per second, the RTX 3070 node around 750,000 passwords per second, and the A6000 node approximately 2 million passwords per second. As can be seen in the table, employing longer passphrases yields enhanced security. This applies even to a single node. Expanding the attack by adding nodes would not significantly alter the outcome. It is crucial to note that this assessment only considers standard computing units and not specialized hardware tailored for password attack purposes. 2. Dictionary attack: Passphrases are generally considered more secure due to the considerable time required by brute-force attacks. However, they often pose a challenge in terms of memorization. Hence, many Wi-Fi networks resort to spoken words or phrases, a method increasingly adopted by access points preconfigured by ISPs. To assess the resilience of such measures against password attacks, various password formats were amalgamated. Although numerous combinations exist, the analyzed configurations provide insight into the requisite duration of the attack. We considered passwords that comprise the 1000 most common English words, 5000 English words, 20,000 English words, and 50,000 English words mixed with numbers. The number of possible combinations was calculated using the following equation:  
\[Number\ of\ possible\ combinations=\ I!\prod Mi \tag{5}\]  
where \(I\) is the number of total elements in the passwords. \(Mi\) is the number of possible combinations of each element. Ensuring robust password security is particularly critical when passwords contain common English words. However, the lack of an optimized industry-specific dictionary presents a significant obstacle. In this project, our aim was to develop dictionaries of varying sizes and evaluate their effectiveness against potential attacks. When discussing the breadth of the English language, it is important to note three key figures: there are over a million total words, with approximately 170,000 words currently in use, and a typical individual's vocabulary comprising 20,000-30,000 words. To assess the vulnerability of passwords to dictionary attacks, we analyzed different word set sizes. The results of these tests are detailed in Table 3.
## 2 Study Area, Data, and Methodology
### Data and Methodology
#### 2.2.2 MODIS Urban Extent  
The urban extent of the cities, used in this analysis, was derived from the MODIS urban area product [92]. This 250 m MODIS global urban area product (MGUP), available from 2001 to 2018, is one of the best and contemporary global products for urban extent that has been compared with other similar urban extent datasets. A locally adaptive and automated global mapping method for accurate urban maps was used to produce an updated 250 m MODIS global urban area product (MGUP) from 2001 to 2018. The method involves automated sample extraction, locally adaptive sample selection, and post-processing in a spatio-temporal context. The urban extent is processed to fill small holes and obtain a relatively uniform perimeter using morphological filters. The MGUP has a F-score of 0.88, outperforming contemporary global products. The latest 2018 urban extents, derived from MODIS observations (MGUP), were used in this study.
# Robust Symbol and Frequency Synchronization Method for Burst OFDM Systems in UAV Communication
## 4 Performance Analysis  
### Symbol Timing Synchronization Performance  
In this section, the symbol timing synchronization performance is evaluated in terms of detection probability. In the simulations, a ZC sequence with length \(L=128\) and root index \(u=127\) is employed. The sub-carrier spacing is 15 kHz; hence, the bandwidth of the preamble is 1.92 MHz. For the additive white Gaussian noise (AWGN) channel, the received signal can be given in the following composite model:  
\[\left\{\begin{array}{l}\mathcal{H}_{0}:r(n)=w(n)\\ \mathcal{H}_{1}:r(n)=s(n)+w(n)\end{array}\right., \tag{23}\]  
where \(\mathcal{H}_{0}\) represents the null hypothesis in which the preamble is not present and \(\mathcal{H}_{1}\) represents the alternative hypothesis in which the preamble is present. In this work, a correlator is considered at the receiver end, and thus, the  
Consequently, the false alarm probability is expressed by  
\[P_{fa}=\int_{V_{th}}^{+\infty}f(z|\mathrm{H}_{0})dz\approx\exp\left(-\frac{V_{th}} {2\sigma^{2}}\right). \tag{26}\]  
According to Equation (26), \(V_{th}\) can be expressed as an inverse function of \(P_{fa}\):  
\[V_{th}=-2\sigma^{2}\ln(P_{fa}). \tag{27}\]  
Moreover, the correlation value \(V(n)\) is subject to a non-central \(\chi^{2}\) distribution when \(\mathcal{H}_{1}\) is true, and the PDF of \(V(n)\) can be expressed as  
\[f(z|\mathrm{H}_{1})=\frac{1}{2\sigma^{2}}\exp\left(\frac{z+L^{2}}{2\sigma^{2} }\right)I_{0}(\frac{L\sqrt{z}}{\sigma^{2}}),z\geq 0. \tag{28}\]  
As a result, the detection probability \(P_{d}\) can be expressed as  
\[P_{d}=\int_{V_{th}}^{+\infty}f(z|\mathrm{H}_{1})dz=\mathrm{Q}\left(\sqrt{2L \times SNR},\sqrt{-2\ln(P_{fa})}\right), \tag{29}\]  
where \(SNR\) is the signal-to-noise ratio of the received signal and \(\mathrm{Q}(a,b)\) is the Marcum Q-function defined by  
\[\mathrm{Q}(a,b)=\int_{b}^{+\infty}x\exp\left(-\frac{x^{2}+a^{2}}{2}\right)I_{ 0}(ax)dx. \tag{30}\]
# Magnetic Nanoparticles: Synthesis, Characterization, and Their Use in Biomedical Field
## 2 Synthesis Methods
### Chemical Methods
#### 2.2.6 Microemulsion Method  
Microemulsion is a system of water, oil, and an amphiphilic surfactant that forms a stable, thermodynamically stable dispersion. The process involves the incorporation of precursor materials into different phases of the microemulsion, leading to NP formation. Chemical reactions occur within the confined spaces of the microemulsion droplets, leading to the formation of nanoparticles [55].  
Different variations of microemulsion methods exist:  
* **reverse microemulsions**, where water is dispersed in an oil phase with a surfactant;
* **direct microemulsions**, where oil is dispersed in a water phase with a surfactant;
* where both oil and water are present in a comparable amount [56].  
The advantage of using the microemulsion method is precise control over NP size, shape, and composition [55]. Several parameters (water-to-surfactant ratio, concentration of the reactants, and surfactant film flexibility) influence the size of MNP microdroplets [57]. This method's drawbacks are polydispersity, a low yield of NPs, large solvent volumes, and poor versatility in metal precursors compared to coprecipitation and thermal decomposition [17].
###### Abstract  
Structural Health Monitoring (SHM) of composite structures leads to greater safety during operation and reduces the cost of regular inspections. Impact damage detection is an important SHM task. Since impact damage can significantly reduce the lifetime of composite structures, sensors for impact damage are of great interest. Carbon Fiber Sensors (CFSs) can be used to detect composite damage. CFSs are lightweight and compact, and they can be integrated during the manufacturing process. In our study, CFSs were manufactured from three types of carbon fiber tows and were integrated into different layers of the lay-up in order to investigate the influence on impact damage detection. The effect of mechanical loading and temperature change on the measured electrical resistance was investigated during cyclic flexural tests. It was revealed that, it is possible to distinguish between changes in measured signals due to impact and due mechanical loading. The change in the measured electrical signal caused by temperature can be eliminated. CFSs can be used for impact damage detection of a glass fabric composite. A combination of thermography and CFSs as an active heating element also provides good results in the field of impact damage detection  
SHM; piezo-resistive sensor; carbon fiber sensor; impact damage; polymer composites; sensor embedment; NDT; active thermography Article
###### Abstract  
Fixed-wing unmanned aerial vehicles (UAVs) are widely considered as a vital candidate of aerial base station in beyond Fifth Generation (B5G) systems. Accurate knowledge of air-to-ground (A2G) wireless propagation is important for A2G communication system development and testing where, however, there is still a lack of A2G wideband channel models for such a purpose. In this paper, we present a wideband fixed-wing UAV-based A2G channel measurement campaign at 2.7 GHz, and consider typical flight phases, based on which a wide-sense stationary uncorrelated scattering (WSSUS)-based tapped delay line (TDL) wideband channel model is proposed. Parameters of individual channel taps are analyzed in terms of gain, amplitude distribution, Rice factor and delay-Doppler spectrum. It is shown that UAV flight phases significantly influence the channel tap parameters. Particularly, the \"Bell\"-type spectrum is found to be the most suitable model for the delay-Doppler spectrum under various flight scenarios for A2G propagation. The proposed channel model can provide valuable assistance and guidance for UAV communication system evaluation and network planning.  
air-to-ground communication; channel measurement and modeling; delay-Doppler spectrum; tapped delay line model +
Footnote †: journal: Advances in Neural Information Processing Systems
# Targeted Delivery Strategies for Hydrophilic Phytochemicals
## 3 Hydrophilic Phytochemicalemicals
### Flavonoids
#### 3.1.2 Hydroxyl Groups, Glycosylation, and Polarity  
Water solubility of flavonoids strongly depends on the number and placement of hydroxyl groups, the presence of glycosides, and structural modifications such as sulfonation, acetylation, or glycosylation [115; 117; 118; 119; 120]. As demonstrated by [PERSON] et al. (2002), a higher number of hydroxyl groups significantly increases molecular polarity and hydrogen bonding potential, directly improving water solubility [119]. As described earlier in the context of quercetin, luteolin, and apigenin, glycosylation with sugar moieties like glucose or rhamn enhances hydrophilicity, leading to greater water solubility and bioavailability [119]. For instance, quercetin-3-O-glucose exhibits much higher solubility compared to its aglycone form, which directly influences its absorption and distribution in biological systems [119]. Similarly, luteolin-7-O-glucose and glycosylated derivatives of apigenin demonstrate improved solubility and stability in aqueous environments, which enhances their biological effectiveness [119]. Despite its high number of hydroxyl groups, quercetin in its aglycone form has low water solubility (approximately 0.92 g/L at 25 \({}^{\circ}\)C) [115]. However, glycosylation or encapsulation in \(\beta\)-cyclodextrintrins increases its solubility and stability, forming hydrophilic-lipophilic inclusion complexes that improve bioavailability and protect against degradation [115].
## 6 The Lamp Post  
The lamp posts use, as new technologies, Light Emitting Diodes (LEDs) for the illuminating lamps and photovoltaic energy (PV) to supply the power. The use of these technologies is known in the literature, but a preventive traffic study allowed precisely defining the load allowing the correct dimensioning of the PV elements size.  
Figure 5: The system placed in a shelter for laboratory tests.  
Figure 6: Test system in the field.  
The choice to supply the lamp posts of an alternative energy source is imposed by the absence of mains in the area where the isle is placed, and strongly suggests the use of this kind of energies in areas where the mains is far away. In fact, it would be very expensive (requiring copper wires and civil engineering works) to connect the area. Among the alternative energies, the absence of a constant wind, suggested to us that the best alternative energy to use is the photovoltaic one. PV systems are composed of a PV panel, a battery and a battery recharger [35].  
The choice of the PV elements' size has been studied to match the operative conditions of the lamp posts. To evaluate the load, a preventive check of the car transit along the street has been made for four months during winter and spring when the nighttime has a longer duration. Every night we registered an average passage of about one hundred cars, often passing in group of two-four cars each time. For each transit of cars, we fixed 30 s for the lighting of the lamps so, the worst case provides that the total time the lamps need to be lit every night is about 25 min. Considering also anticipated some emergency situations, our system provides energy for one hour and a half. We also considered natural and weather conditions; in fact, we chose a larger battery to compensate for low sunlight for several days. Considering the loads, we have three different combinations:  
(1) for the presence sensor card (0.2 A current consumption) the battery has a capacity of 6 Ah and the PV panel has a maximum power of 9 W-12 V; this assures a functioning of 10 h for three consecutively nights;  
(2) secondary lamp posts use a 19 W-12 V PV panel and a battery of 10 Ah capacity able to ensure two hours per night of use for three consecutively nights;  
(3) the coordinator lamp post has higher a consumption than the secondary ones because it has also the Raspberry-Pi (current consumption 0.5 A), which must be always connected to the Internet during the night and the WiMAX modem/router, which is activated only for two times during the night 15 min every time. To limit the consumption, the lamp section is managed like the secondary lamp posts, so the PV panel has a peak of 95 W-12 V and the battery a capacity of 48 Ah which assures an activity of 2 hours/night and the full activity for the hub for three consecutive nights. The modem average power consumption is about 20 W.  
Obviously, the consumption, and consequently the PV panels, the batteries' sizes and the costs, would be at least three times higher without the intelligent management system; moreover, the lower weight produces less stress on the mounting poles.
## 4 Discussion
In this study, foreground selection, using the closely linked molecular markers \(F3^{\prime}H\)-F/R and _Pur7.1_-K1 from the donor parents SN60 and BT126, respectively, and background selection, using microsatellite markers in the genetic background of the recurrent parental genome [58], provided practical tools to ensure accurate transfer of non-anthocyanin and anthocyanin-rich traits in early generations while recovering the majority of the genome of the recurrent parent LF02 in the advanced backcross generations. The genetic background recovery percentage is an important issue considered in backcross breeding, and it is difficult to accurately reflect the genetic similarity between improved selected lines and recurrent parents in traditional agronomic character investigation [59; 60]. In this study, in order to retain the elite traits of the recurrent parent, genotype comparison between improved selected lines and recurrent parents was conducted using SSR markers to evaluate the background recovery rate in backcross breeding. Individualswith high background recovery percentages were selected to participate in the next round of backcrossing, and the background recovery rate was more than 85% in BC3F2 individuals. Using MAS combined with backcross breeding, the green or purple trait improvements in the existing excellent broccoli varieties was completed within 3-4 years. Many downny mildew-resistant, heat-stress-resistant, and clubroot-resistant broccoli varieties have been successfully developed using MAS [61; 62]. Many cultivars producing obvious purple heads have been selected for their rich anthocyanin contents, such as \"Purple Sprouting Early\" [63]. As a functional and nutrient-rich food, one of the most outstanding characteristics of purple sprouting broccoli is its winter hardness. The Organic Seed Alliance evaluated \"Red Head\", \"Red Fire\", and \"OSA 206\" as the most winter-hardy purple sprouting broccoli varieties, with survival rates ranging from 44% to 78% at temperatures down to \(-10\)\({}^{\circ}\)C in 2014 and 2015. Green broccoli lines developed using SN60 as the donor parent appeared more attractive with completely green heads. This color trait could be associated with a loss of function of the \(F3^{\prime}H\) gene affecting the anthocyanin biosynthesis. The purple lines derived from BT126 had significantly higher productivity, but the anthocyanin contents were not significantly different between the 20 PBLs and BT126 lines. The 20 PBL23, 20 PBL62, 20 PBL103, 20 GBL47, and 20 GBL128 lines produced higher head lengths, head diameters, and head weights, which are the key components of productivity. The materials obtained from the backcross breeding in this study also provided the parent materials for the breeding of next-generation hybrids.
## 4 Results and Discussion
### Performance Analysis
#### 4.1.5 Packet Loss Ratio (PLR)  
The packet loss ratio measures the percentage of data packets that fail to reach their destination in a network. Along the same path to establish the success of BSHNN, a thorough look at PLR was executed. The acceptable rate ranges from 0 to 3%. The proposed method uses a single-spiking neural network optimized for packet classification, efficiently monitoring packet arrivals through distributed controllers. This method mitigates the risk of a single point of failure in a network. Figure 7a illustrates the observed packet loss rate across various percentages of attacks. It clearly depicts that even with an increasing number of switches, there is practically a drop in the failure ratio.  
The proposed BSHNN method has a lower packet loss rate than the ML-IDP method, especially in scenarios with expanding network infrastructure. The distributed control and classification mechanisms contribute to a more resilient and reliable network, enhancing packet delivery and minimizing losses despite increasing attack percentages and network complexity. This makes the BSHNN approach particularly effective in minimizing packet loss.
## 1 Introduction
We propose an action-masked Proximal Policy Optimization (PPO) algorithm that adapts to time-varying independent channels and randomly arriving tasks while ensuring reliable task transmission. Our main contributions are summarized as follows:  
* We introduce a low-latency MEC network where tasks are composed of multiple data packets transmitted by various UEs through wireless channels to an edge server under the FBL regime. We analyze the impact of blocklength allocation and UE selection on the error probability of data packet transmission and the task AuD. * We formulate an optimization problem to minimize the average task AuD by jointly allocating blocklength and selecting UEs while ensuring error probability constraints. Subsequently, we transform this into a UE selection problem that adheres to the error probability constraints dictated by the FBL regime. * We propose an Error Probability-Controlled Action-Masked Proximal Policy Optimization (EMPPO) algorithm considering dynamic task generation and random fading channels. By masking actions that cannot satisfy error probability constraints, our algorithm prevents the exploration of ineffective actions, thereby enhancing efficiency. * Simulation results are provided to validate the performance of our proposed method compared to server baseline methods, especially the standard DRL methods. We demonstrate the robustness of our method under various network conditions, such as varying task arrival probabilities, channel correlation coefficients, and Signal-to-Noise Ratio (SNR). The rest of the paper is organized as follows: In Section 2, we describe the low-latency MEC system model and FBL performance and task AuD. We state the optimization problem of minimizing the task AuD and present an action-masked DRL algorithm in Section 3. Then, we evaluate the performance and show the simulation results in Section 4. Finally, we conclude our work in Section 5.
## 4 Conclusions  
The main goals of this paper were to determine the structural features and evaluate the rheological properties of a sulfated xylogalactan-enriched fraction extracted from the Tunisian red seaweed _J. adhaerens_. The structural analyses revealed that JSP (M\({}_{\rm w}\) = 8.0 \(\times\) 10\({}^{5}\) Da) was mainly composed of an agar-like xylogalactan with a repeating backbone of (\(\rightarrow\)3)-\(\beta\)-d-Gal\(p\)-(1,4)-\(\alpha\)-t-Gal\(p\)-(1\(\rightarrow\))\({}_{\rm n}\) and (\(\rightarrow\)3)-\(\beta\)-d-Gal\(p\)-(1,4)-3,6-\(\alpha\)-t-AnGal\(p\)-(1\(\rightarrow\))\({}_{\rm n}\) substituted mainly on the \(O\)-6 of the \(\beta\)-(1,3)-d-Gal\(p\) by \(\beta\)-xylosyl side chains, less with sulfate or methoxy groups, but also on the \(O\)-2 and \(O\)-3 of the \(\alpha\)-(1,4)-t-Gal\(p\) with methoxy and/or sulfate groups. The rheological investigations showed that JSP solutions exhibited a shear-thinning behavior and a great viscoelastic character with a critical overlap concentration (C*) close to 7.5 g/L. JSP physicochemical properties are at least as good as other polysaccharides from red marine seaweeds currently used for their functional properties as hydrocolloids. _J. adhaerens_ could be a new feedstock for agaroids in Tunisia even if it seems hard to penetrate the international market of phycocolloids given other main macroalgae producers. Finally, these findings would help the development of novel bioactive polysaccharides for niche markets.  
Figure 8: Storage modulus (\(G^{\prime}\)) and loss modulus (\(G^{\prime\prime}\)) vs. angular frequency (rad/s) for JSP aqueous solutions for different concentrations (1.0–2.0%, _uv/v_) at 25 \({}^{\circ}\)C in water.  
Figure 9: Critical overlap (C*) concentration obtained from the log-log plot of the specific viscosity (\(\eta_{pp}\)) vs. the concentration of JSP in water at 25 \({}^{\circ}\)C.  
**Author Contributions:** [PERSON] prepared and carried out all the experiments and also wrote the manuscript. [PERSON], [PERSON] and [PERSON] helped perform the extraction, FTIR and GC/MS experiments. [PERSON], [PERSON] and [PERSON] carried out the NMR and SEC/MALLS experiments respectively. [PERSON], [PERSON] and [PERSON] conceived and coordinated the work. [PERSON] revised all the manuscript. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This work has been sponsored by the Tunisian Ministry of higher education and scientific research and Campus France (714305B) (Eiffel scholarship program of excellence, 895151J)).  
**Conflicts of Interest:** The authors declare no conflict of interest.
# Real-Time Tomography of Gas-Jets with a Wollaston Interferometer
## 2 The Single Beam Wollaston Interferometer Setup
### Theory
the laser beam will result in a shift of the fringe spacing \(S\), since rays passing through this medium will pick up an additional phase shift with respect to the unperturbed rays.