esa-sceva/satcom-chunk-collection huggingface dataset:
# Sensitivity Analysis of Multi-Temporal Sentinel-1 SAR Parameters to Crop Height and Canopy Coverage
## 1 Introduction
The objective of this study is to evaluate the sensitivity of different Sentinel-1 dual polarimetric SAR parameters to crop height and CC of maize, sunflower and wheat, and to investigate the changes in SAR backscatter arising from crop height and CC during crop phenological stages.
## 3 Results and Discussion
### Bioaccumulation Factors of Heavy Metals in Vegetables  
Metal BAF and Translocation Factor (TF) can used to evaluate metal uptake and transport by plant tissues, and TF values > 1 indicate the accumulation of metals under natural conditions [44].  
Figure 2: The comparison of metal levels in different vegetables of control, group 1 and group 2: (**a**) Cd level; and, (**b**) Cu level (mg/kg F.W.).  
Figure 3 shows the BAF of both Cd and Cu for all of the observed vegetables in group 1. The highest BAF for Cd was in water spinach (0.29), and the highest BAF for Cu was in potato (<0.01). [PERSON] et al. [45] indicated that Cu was mainly accumulated in the root and leaf parts. It is well known that BAF variation depends on the metal, the plant species, soil pollution level, and soil acidity [29]. For example, BAF values were found to be >1 for Cr, Cd, Cu, Mn, Pb, and Zn in bersseem clover (_Trifolium alexandrinum_) [44], which indicated that bersseem was a suitable accumulator of these metals in natural conditions. [PERSON] et al. [46] indicated that the TF value for Pb was >1 in maize shoots in three different soil textures. However, BAF for Cr, Ni, Cu, Cd, and Pb in cabbage leaves and broccoli heads were all <1, which revealed that cabbage and broccoli were poor accumulators [47]. We can conclude that BAF and TF are dependent on vegetable species and each metal. In the present study, although the BAF values in all plants were <1, the accumulation of Cd was higher than Cu specifically, consistent with reports from previous studies [16; 48; 49], as well as TF for Cd was also higher than for Cu [50]. In addition, [PERSON] [51] indicated that the solid-water distribution coefficient (Kd) of different metals influenced the distribution of chemicals migration into water from soil when Kd is low. For example, the uptake of Cd by Indian mustard and lettuce varied because of the larger root system in mustard and the planting season [52]. In conclusion, BAF varied depending on the properties of the observed heavy metals and vegetables.  
The soil characteristics may influence the absorption ability of metal contaminants. For example, the components of clay, silt, and sand are relevant to the superficial content of soil, and positively related to the metal accumulation [53]; the ratio of clay > silt > sand of Cd-contaminated soil might provide high superficial content and high accumulation of Cd as compared to Cu. Meanwhile, high organic matter will cause a high adsorption of metals in soil, reducing their migration to cultivated plants [54]. The present study also showed a correlation between organic matter and Cd in water spinach, and organic matter and Cu in tomato and potato by Spearman correlation analysis (Tables S2-1 to S2-10). Therefore, the different components and characteristics of soil will influence the transportation and accumulation of metals.
## 3 Results and Discussion
### Wound-Healing Effect of AgNP in a Murine Incisional Acute Wound Model  
In vivo preclinical wound-healing research commonly uses mouse models, either incisional or excisional (2018). In order to formulate AgNP in a semisolid pharmaceutical form, a hydrogel containing AgNP and the respective placebo were prepared. Semisolid formulations are convenient forms for topical applications since they increase the drug residence time on the skin (2018). The gel composition was selected from a previous study, as it showed compatibility with human skin without any irritation signs (2018). A gel containing 1.5 mg/mL AgNP was used to assess the healing performance of AgNP. The topical administration of the AgNP gel produced, of Silvederma(r), a commercial cream of silver sulfadiazine (10 mg/g), and of the placebo started on day 0, and wounds were treated in the following 7 days. In Figure 9A, representative photos of the skin incision treatments at different time points are shown. During the assay, the body weight variation was less than 10% and not statistically different between the groups. As can be seen in the graphic (Figure 9B), mice treated with the placebo had a larger wound area, which was different from that present on mice treated with Silvederma(r) or AgNP (\(p<0.05\)). Statistically, there is no difference between Silvederma(r) and AgNP. Non-treated wounds increased in area in the initial 2-3 days, an indicator of the variable expansion of wound margins [52]. This phenomenon was not observed in the groups treated with Silvederma(r) or gel containing AgNP. The placebo wounds did not complete closure during the 7 days of the trial. Silvederma(r) has a higher silver concentration than the AgNP gel, both ensuring rapid wound closure. These results are very encouraging and highlight the potential of AgNP in wound healing.  
The histological results presented in Figure 10 confirm that wound closure was successful in the groups treated with AgNP and Silvederma(r). Figure 10A shows that the wound treated with the placebo did not close. The healing process looks more advanced with the AgNP formulation compared with silver sulfadiazine. The histological analysis corroborates the results obtained in the wound area evaluation (Figure 9).  
Figure 9: The wound-healing effect of AgNP in a murine acute incisional wound model. (**A**) Representative images of the incisional wounds on days 1, 5, and 7 of treatment with the placebo (vehicle of AgNP gel), AgNP gel, and Silvederma® cream (silver sulfadiazine 10 mg/g). (**B**) Wound area evaluation during treatment with the placebo gel, Silvederma® cream, and AgNP gel. Data are expressed as the mean \(\pm\) SEM of 3 independent measurements. Statistics: one-way ANOVA followed by [PERSON]’s post hoc test. * \(p<0.05\) vs. control.
## 1 Introduction
cavity clouds likely undergo a violent collapsing stage. Collapse events of cavitation structures behind a ship's propeller, for instance, can lead to very high-pressure peaks, and such peaks can exhibit very rapid temporal variation. As noted by [PERSON] [8], a primary source of high-frequency noise is the collapse of the free cavitation bubbles. The shedding behavior is mainly governed by the development of the re-entrant jet, vortical structures and turbulent flow near the foil, i.e., the unsteady dynamics of especially the liquid phase. As Reynolds-averaged Navier-Stokes (RANS) equations are mainly derived for steady single-phase flows, complex unsteady phenomena may be severely under-predicted when using an unsuitable turbulence-modelling approach. High-fidelity turbulence modelling is typically needed to capture a detailed flow field for the prediction of the dynamics of cavitation and its consequences such as erosion and noise [9; 10; 11; 12]. Therefore in this study, we employ two different turbulence closures: an unsteady RANS-based SST \(k-\omega\) turbulence model and a hybrid RANS/LES (large eddy simulation) closure called the delayed-detached eddy simulation (DDES). We analyze the two-phase flow using a compressible multiphase model. Cavitating problems have been typically treated with incompressible flow solvers [13; 14; 15; 16; 17] (especially in the case of marine propellers), and recently either isothermal compressible or fully compressible flow formulations have been used as well [18; 19; 20; 21]. If we aim for a precise treatment of hydrodynamic cavitation in its various forms, a compressible multiphase flow model is a requisite for reliable numerical predictions [18]. Peculiarly, the sound speed in a mixture can drop to a fraction of that in the liquid and even the vapor phases. Prediction of the correct acoustic signal speeds calls for a complete flow model. In this paper, the dynamics of the unsteady sheet cavitation is studied in detail. We employ a compressible two-phase flow model to account for the cavitation phenomena, and the computational case is the ITTC standard cavitator [22]. The results are compared to the model tests carried out in a cavitation tunnel. The flow simulations have been conducted with the general purpose CFD solver Finflo. The cavitation tunnel tests, which include hydrophone measurements of the underwater noise, have been conducted at SVA Potsdam. We have carried out simulations of two different cases. The inflow velocity for both cases was 8 m/s, and the cavitation numbers were \(\sigma=[0.53,1.27]\). To the knowledge of the authors, our results include the first reported numerical studies of the ITTC standard cavitator. This paper is organized as follows. Section 2 describes the flow solver used, as well as the turbulence and multiphase flow modelling. In Section 3 we describe the test case. Section 4 presents the results in terms of cavitation observation and its dynamics, and their comparison to the experimental findings. Lastly, we present conclusions and suggestions for future work in Section 5.
# A Hardware-Efficient Vector Quantizer Based on Self-Organizing Map for High-Speed Image Compression
## 5 Conclusions  
Based on the SOM algorithm, we present a hardware-efficient vector quantizer to alleviate the challenges of insufficient bandwidth and storage in the high-speed vision system. A RCBAT circuit, which can be reconfigured both into the codebook learning mode and image encoding mode, is proposed to improve the hardware efficiency of our design. To achieve a high processing speed, we propose a multi-parallel architecture, where the codebook is evenly distributed into numerous sub-blocks. Moreover, by adopting a mechanism of PVCS, our vector quantizer easily acquires the advantage of adjustable compression ratio. Finally, a verification system is developed based on the FPGA. The experimental results indicate that the hardware resource usage and the achievable compression speed of our design are respectively \(8\%\) lower and \(33\%\) higher than that of the previous work. Overall, our proposed vector quantizer can effectively achieve a higher compression speed while keeping a lower hardware usage compared with the conventional design.  
\begin{table}
\begin{tabular}{l l l l l} \hline \hline
**Design** & **[11]** & **[13]** & \multicolumn{2}{l}{**This Work**} \\ \cline{3-5}  & & & \(k\) = 16 & \(k\) = 32** \\ \hline FPGA family & Virtex II & Virtex IV & Stratic IV & \\ \hline Compression ratio (CR) & 16 (Fixed) & 3 (Fixed) & \(\geq\)16 (Adjustable) & \\ \hline PSNR (dB) & 31.28 & 37.10 & 30.69 (CR = 16) & \\ \hline Frequency (Hz) & 71.43 M & 19.6 M & 80.1 M & 79.8 M \\ \hline MCPS & 11,026 & N/A & 14,247 @ CR = 16 & 21,845 @ CR = 16 \\ \hline LUTs & 40,280 & 17,6130 & 37,214 & 74,368 \\ \hline \multirow{3}{*}{Compression speed (frames/s)} & \multirow{3}{*}{160} & \multirow{3}{*}{107} & 212 @ CR = 16 & 324 @ CR = 16 \\  & & & 275 @ CR = 64 & 500 @ CR = 64 \\ \cline{1-1}  & & & 296 @ CR = 256 & 585 @ CR = 256 \\ \hline \hline \end{tabular}
\begin{tabular}{l l l l} \hline \hline
**FPGA: field programmable gate array; PSNR: peak signal-to-noise ratio; MCPS: million connections per second;** \\ \hline LUT: look-up table.  
\end{table}
Table 2: Comparison results with the previous VQ (Vector quantization)-based image compression circuits.  
**Acknowledgments:** This work was supported by National Key Research and Development Program of China under Grant 2017 YFA0206104, Shanghai Municipal Science and Technology Commission under Grant 16511108701, Zhangjiang Administrative Committee under Grant 2016-14, and China Scholarship Council.  
**Author Contributions:** The design was conceived by [PERSON] and [PERSON]. [PERSON] performed the experiments, analyzed the data and wrote the manuscript under the supervision of [PERSON], [PERSON], [PERSON], and [PERSON]. [PERSON] and [PERSON] provided technical support for architecture implementation.  
**Conflicts of Interest:** The authors declare no conflict of interest.
# ZSM Framework for Autonomous Security Service Level Agreement Life-Cycle Management in B5G Networks
## 4 ETSI PoC
### Security Assets
#### 4.1.2 I2 NSF Agent  
The I2 NSF IPsec solution [45] enables dynamic VPN deployments by employing a centralized controller to handle requests for securing the traffic between private networks. In the presented scenario, two I2 NSF agents are autonomously deployed establishing an IPsec tunnel between the RAN and the computing nodes hosting 5G core components, encrypting and securing all traffic cross-domain. Agents are managed via a controller and utilize the keless model eliminating the dependency of agents on IKE protocols [46] for key material establishment, Security Associations, and rekey processes since all the configuration parameters are provided by the controller.  
Concerning the policy extension, channel protection capability has been enhanced with the IPsec configuration action, which extends channel protection with new fields and available values for confidentiality and integrity to be compliant with cypher suites needed for private 5G networks' interconnection to public base stations. The plugin takes this policy to build a configuration containing: (i) the networks to be interconnected via the IPsec tunnel, (ii) the addresses of the agents, and also, (iii) security parameters for IPsec, such as encryption and integrity algorithms, the lifetime of the SA for rekeying, and the lifetime of the SA to be removed in case the rekeying process fails. The configuration driver uses the I2 NSF controller's REST API to pass these parameters. The I2 NSF controller then generates the necessary key material (e.g., initialization vectors and keys), Security Policies (SPs), and SAs. The configuration is securely transmitted to the agents using NETCONF, employing the ietf-ipsec-ikeless YANG model [45]. During the rekeying process, the controller must be subscribed to the agents' NETCONF notifications. These notifications inform the controller when an SA is about to expire, enabling it to generate and provide the key material required for the new SA. This ensures seamless security operations without interruption.
# A Tutorial on Retroreflectors and Arrays Used in Satellite and Lunar Laser Ranging
## 6 Velocity Aberration and \"Spoiled\" Retroreflectors
Furthermore, the effective area and peak cross-section of each lobe is reduced to  
Figure 8: The maximum (red) and minimum (blue) values of the parameter \(\alpha\) as a function of the satellite altitude, \(h_{\mathrm{s}}\). By the time one reaches geosynchronous altitude of 36,000 km, the two curves converge to roughly the same value of \(\alpha\). Figure 9: Far-field diffraction pattern (FFDP) of a retroreflector “spoiled” in all three axes. To simplify the drawing, the six resulting lobes are shown as circles, but, in reality, they are better described by the two-dimensional Fourier transform of either a triangular aperture or a 60-degree sector of a circle. \[A_{eff}=\eta(\theta_{inc})\frac{A_{cc}}{2N}\] (14a) and \[\sigma_{peak}=\eta^{2}(\theta_{inc})\frac{\sigma_{cc}}{\left(2N\right)^{2}} \tag{14b}\]  
Since the return signal is weakest at the lowest elevation tracking angle, choosing \(\gamma=\alpha_{min}\) places the peak of the lobe there, but any lobe energy inside the dark inner ring or outside the dark outer ring is wasted. Filling in the circumferential gaps between the lobes produced by'spoiling\" can be accomplished by rotating cubes by an angle equal to \(60^{\circ}\) divided by an integer greater than one, generally referred to as \"clocking\". A larger-diameter cube will result in smaller lobe dimensions and will reduce the spillover into the region outside the active angular ring, but it may also create a larger angular spacing between lobes, which in turn may require more clocking positions, as shown in Figure 10.
# Enhancing Sustainable IoT Systems Through a Goal-Oriented Requirements Analysis Framework
## 2 Fundamentals
### The Internet of Things  
The IoT is a versatile paradigm that enables interconnected devices to collect and exchange information from the surrounding environment for a wide range of applications. These include notification systems that inform customers about supermarket discounts when they are near them, food ordering applications that facilitate meal planning and grocery shopping, automotive monitoring solutions that track fluid levels to ensure optimal vehicle performance, and wearable devices capable of real-time heart rate monitoring, among others. Unlike traditional computing and monitoring systems, IoT is characterized by small, frequent data transmissions and the capacity to support a vast number of connected devices, distinguishing it from conventional approaches. The rapid evolution of IoT technologies has led to their widespread adoption in various domains, making them an integral component of modern digital ecosystems [16].  
The IoT disseminates data to both users and various systems or software. As an illustration, when it comes to users, the IoT can transmit health-related information through software that collects data from sensors responsible for monitoring vital signs. Additionally, in numerous instances, businesses or individuals have the capability to remotely control a device to perform tasks, like activating the garage lights or scheduling an office air conditioning system to start refreshing the environment at 9:00 am in anticipation of employees' arrival.
# Quantifying Uncertainties in OC-SMART Ocean Color Retrievals: A Bayesian Inversion Algorithm
## 2 Oc-Smart
### Application  
Currently OC-SMART supports ocean color data retrievals from 11 multi-spectral and hyper spectral sensors onboard satellites operated by the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), the Korea Institute of Ocean Science and Technology (KIOST), and the China Meteorological Administration (CMA), which include SeaStar/SeaWiFS (NASA), MODIS/Aqua (NASA), SNPP/VIIRS (NASA/NOAA), ISS/HICO (NASA), Landsat/OLI (NASA), DSCOVR/EPIC (NOAA), Sentinel-2/MSI (ESA), Sentinel-3/OLCI (ESA), GCM-C/SGLI (JAXA), COMS/GOCI (NASA), and FengYun-3D/MERSI (CMA). The performance of OC-SMART was first tested using an independent synthetic testing dataset. Then the ocean color products retrieved by OC-SMART were validated against in situ measurements from MOBY [38], SeaBASS [39], and AERONET-OC [40] data for several sensors.  
As alluded to in Section 1, it is important to address uncertainties on a pixel by pixel basis for satellite retrievals to gain confidence in the inferred results. This task is difficult for a neural network designed as a regressor, which generally returns a single predicted value instead of a probability distribution. To form uncertainty estimates on a pixel by pixel basis we have adopted a Bayesian approach in which uncertainties of measured TOA radiances and _a priori_ information are used to quantify uncertainties in the retrieval parameters delivered by OC-SMART. This approach is described in detail in Section 3 with a summary of the processing chain illustrated in Figure 1 of Section 3.5 and with application of this approach shown for various regions and several sensors in Section 4.
# Visible Light Communication: An Investigation of LED Non-Linearity Effects on VLC Utilising C-OFDM
## 4 Conclusions  
The LED non-linearity phenomenon significantly impacted the performance of the optical OFDM system. The DC bias point was one of the key characteristics that influenced the distortion in the LED-transmitted information. In this paper, we proposed C-OFDM to investigate the influence of the LED nonlinear behaviour in optical OFDM wireless communication systems. We comparatively simulated the BER performance of C-OFDM against F-OFDM and the conventional OFDM. The results confirmed that a BER of \(10^{-4}\) could be achieved with C-OFDM at the 900 mA bias point, and that it could not be achieved with the aforementioned OFDM systems. Specifically, the linear region was extended. However, when F-OFDM was employed, we needed to increase the power by 2.5 to realise the BER at 800 mA compared to the C-OFDM. Consequently, the proposed system delivered a better linear region in comparison to F-OFDM and the traditional OFDM. Finally, the C-OFDM system needed a lower energy-per-bit to noise spectral density ratio (\(\mathrm{E_{b}/N_{o}}\)) than standard systems, according to simulation data. As a result, across LED nonlinear regions, a multi-carrier system using the proposed technique would benefit from a low PAPR, and had lower \(\mathrm{E_{b}/N_{o}}\) needs.  
Conceptualization, J.A. and S.B.; methodology, S.B.; software, J.A.; writing--original draft preparation, J.A.; writing--review and editing, S.B. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The data presented in this study are available on request from the corresponding author.  
The authors declare no conflict of interest.
# Driving Behavior Classification and Sharing System Using CNN-LSTM Approaches and V2X Communication
## 4 Performance Evaluation  
In this section, we evaluate the proposed driving behavior prediction and sharing system. The performance of the proposed system is evaluated by 4 layer CNN-2 stacked  
Figure 12: Four-layer CNN-2 stacked LSTM-V2X module.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{2}{c}{**Environments**} & \multicolumn{4}{c}{**Behavior (Ground Truth)**} \\  & **Defensive** & **Normal** & **Aggressive** & **Total Data** \\ \hline \multirow{3}{*}{Simulation} & DGIST & 4440 & 3412 & 3292 & 11144 \\  & Urban & 3777 & 3002 & 1666 & 8445 \\  & Highway & 4257 & 3271 & 3124 & 10652 \\ \hline Real world & DGIST & 2812 & 2248 & 1886 & 6946 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Number of data assigned to labels in the test dataset.  
LSTM's training results, simulations, and real-world test. In addition, the effectiveness of predicted driving behavior sharing on nearby vehicles is also evaluated in the simulation. In a real-world test, experimental results of V2X communication for sharing driving behavior between vehicles are presented.