esa-sceva/satcom-chunk-collection huggingface dataset:
# Oblique Wide-Angle Multi-Sector Metamaterial Absorber for Space Applications
## 3 Measurement  
### Prototypes  
Two panels were realized for each sector. The two panels corresponding to sector A are shown in Figure 7a. The FSSs (Figure 7b) were realized by CIRETEC using two etching sequences. The copper foil and the FSS layer were then attached to the honeycomb using double-sided adhesive film for a total thickness of 41.1 mm. The total size of each prototype is 578 mm \(\times\) 428 mm (Figure 7c) which is approximately 3.9\(\lambda\)\(\times\)2.9\(\lambda\) at 2 GHz. For the sectorial absorber, two panels corresponding to sector A and a sector B were positioned side by side, resulting in a 1156 mm \(\times\) 428 mm structure. The sectorial absorber composed of a panel A adjoined to a panel B is denoted by 'A + B' in the rest of the article.  
\begin{table}
\begin{tabular}{c c c c c} \hline  & **p (mm)** & **g (mm)** & **w (mm)** & **Z (f)** \\ \hline TE (x) & 10.5 & 2 & 0.45 & 444 \\ TM (y) & 15.5 & 1.3 & 0.46 & 283 \\ \hline \end{tabular}
\end{table}
Table 2: Geometrical dimensions of the sectorial absorber B for each polarization.  
Figure 6: Reflection coefficient of sectorial absorbers A and B for both polarizations with respect to angle of incidence. TL model, 2.15 GHz.  
In order to compare the performances of the 'A + B' absorber with the uniform absorbers of the same dimensions, two other configurations were considered corresponding to panel A adjoined to a second panel A (denoted by 'A + A') and panel B adjoined to a second panel B (denoted by 'B + B').
# The Future for End-Stage Kidney Disease Treatment: Implantable Bioartificial Kidney Challenge
###### Abstract  
Despite limited organ availability and post-transplant complications, kidney transplantation remains the optimal treatment for End-Stage Kidney Disease (ESKD). However, innovative dialysis technologies such as portable, wearable, and implantable bioartificial kidney systems are being developed with the aim of addressing these issues and improving patient care. An ideal implantable device could combine bioreactors and blood ultrafiltration to replicate key native cell functions for solute reabsorption, secretion, and endocrinologic activities. Today, the feasibility of an implantable bioreactor for renal cell therapy opens the challenge of developing a fully implantable bioartificial kidney based on silicon nanopore membranes to ensure immunological isolation, cell viability, and the possibility of maintaining a blood substrate for metabolic activities. Current technology is not sufficient to obtain an efficient artificial bioreactor to reach physiological blood purification, which requires a more complex system to produce an ultrafiltrate from the blood that can be processed by cells and eliminated as urine. The number of cells in the bioreactor, endocrine activity, immunological cell isolation, solute and fluid secretion/reabsorption, cell viability, blood and ultrafiltration flow control, and thrombogenicity are fundamental issues that require a new technology that today appears to be a challenge for the design of an implantable artificial kidney. This review aims to analyze the state of the art in this particular field of kidney replacement therapy to highlight the current limitations and possible future technology developments to create implanted and wearable organs capable of treating ESKD with artificial organs that can replicate all native kidneys functions.  
end-stage renal disease; chronic kidney disease; kidney transplant; implantable bioartificial kidney; bioreactor +
Footnote †: journal: selected
## 3 Results and Analysis
### Sensitivity to the Number of Estimators and Samples  
XGBoost was performed on the data set, considering the input vectors (_SNRrh_, _Gr Pn_, and \(\theta\)) and the output vectors (_permittivity_). Estimators are number of trees to fit and samples \(n\) are the numbers of data used. Often the hardest part of solving a machine learning problem can be finding the right estimator for the job. Different estimators are better suited for different types of data and different problems. The figures illustrate the behavior of variable importance estimation for different _estimators_ (500, 4000) and samples, in order to check if the variable importance is still stable when the _estimators_ and the samples \(n\) are changed. The samples \(n\) were set to 2000 and 5000 (Figure 6).  
Figure 5: Two-dimensional data set (**a**) for the SNR and the permittivity (\(\theta=84^{\circ}\)), two dimensional data (**b**) set for the elevation angle and the permittivity (\(SNR=20\) dB).  
Figure 6: Variable importance sensitivity to _estimators_ 500 (**a**) and 4000 (**b**) when \(n=2000\) and 5000.  
In Figure 6, the value of the variable \(SNRrh\) was the highest in these two plots. With the increase of numbers of _estimators_ from 500 to 4000, the value of \(SNRrh\) decreased slightly. \(Pn\) and \(\theta\) increased. We increased the samples \(n\) from 2000 to 5000. The variable \(SNRrh\) shows the same behavior, and \(P_{n}\), \(\theta\) increased slightly. Compared Figure 6a,b, each column with the same samples \(n\), \(Pn\), and \(\theta\) increased, and the value of \(SNRrh\) became lower, but it was still the highest among the variables with a value of 0.4 (40%). In addition, the value of \(\theta\) increased when the number of the _estimators_ and the samples increased but it was still the lowest with a value below 0.1 (10%). In any case, the order of the variable importance was clear and it shows the same importance in those four figures. This phenomenon reports that the value of the variable \(\theta\) (elevation angle) was much lower than \(Pn\) (receiver noise) and \(G_{r}\) (receiver gain), which was around 0.1 (10%), indicating that the elevation angle made less contribution to the permittivity retrieval than the other variables. Furthermore, the received SNR was a predominant variable with a contribution over 40% during the permittivity retrieval.
# Predicting Shot Accuracy in Badminton Using Quiet Eye Metrics and Neural Networks
## 3 Research Gaps Addressed by This Study
### Predictive Modeling of Shot Accuracy  
Previous studies have established correlations between QE and performance [7; 26; 27; 28], but few have developed predictive models for shot accuracy that combine cognitive and physical inputs. Our research contributes by developing a predictive model that offers precise, practical insights for coaches and athletes, applicable in both training and competitive environments.
## 4 Experimental Results  
### Data Generation  
A real-time PEM heap data simulation is configured by containing cells and an active area of 100 cm\({}^{2}\). A real-time numerical simulation is carried out with an active area of 100 cm\({}^{2}\) PEMFC. The numerical work was carried out at various cell voltages ranging from 0 V to 0.95 V under different hydrogen and oxygen humidification [36]. The dataset was considered with 10%, 50%, and 100% humidity levels with different flow channel designs likes two serpentine, three serpentine, serpentine zigzag, straight parallel, and straight zigzag [6]. The experimental study was conducted based on humidity levels.
# Energy-Efficient Wireless Sensor Networks for Precision Agriculture: A Review
## 1 Introduction
To fulfill PA requirements, such as addressing the problems resulting from the long distance between farms and base stations, a mobile data connection service can be established by connecting unmanned aerial vehicles or drones with the base station [4]. Such connection allows the sensor nodes to relay their data to the base station within the wide area of the farm field. However, this solution is limited by the quality of service of WSNs. The main contributions of this paper are summarized as follows:  
1. The potential of using wireless communications protocols or technologies in agriculture was investigated, and the technology with the best power consumption and communication distance was identified. 2. The taxonomy of energy-efficient and energy harvesting techniques was examined to address the power consumption problems in agriculture and to identify those methods that are most suitable for solving these problems. 3. The existing solutions, applicability, and limitations of applying WSNs in agriculture were reviewed and compared. 4. Recent studies using WSN in PA applications based on Internet of Things (IoT) were surveyed and compared in terms of type of sensors and actuators, IoT end devices, IoT platforms, and IoT application layer.
# Research on a Multi-Type Barcode Defect Detection Model Based on Machine Vision
## 4 Experiment and Results Analysis
### Failure Case Analysis  
Figure 13a shows a longitudinal specular highlight generated by intense directional lighting. The resulting abrupt change in local grey-level distribution and spectral characteristics misleads the network into falsely labeling normal stripes as \"scratch/break\" defects. Figure 13b illustrates how the class-confidence overlay applied during object detection partially occludes a 2D barcode. The defect-discrimination module consequently misclassifies the occluded area as a \"missing/damaged\" anomaly.  
Figure 12: Normalized confusion matrix for barcode defect classification using Y8-LiBAR Net.  
Figure 13: Schematic diagram of failure cases.  
These cases reveal two weaknesses: (i) high sensitivity to non-structural interference (specular glare, visual occlusion) and (ii) insufficient coverage of such conditions in the current training set. To address these limitations, we plan the following solutions:  
--Generate large-scale hard negative samples with physics-based rendering and targeted data augmentation that add synthetic glare and partial occlusion, improving robustness to illumination variation and occlusion.  
--Fully decouple the visualization layer from the inference pipeline to ensure the defect-discrimination module processes only clean regions of interest.  
--Introduce illumination-invariant features via masked-auto-encoder pre-training, combined with occlusion-aware attention and uncertainty estimation for adaptive correction.  
--Apply dynamic structural verification in highlight/occluded regions, exploiting barcode redundancy and completeness constraints to further enhance reliability and interpretability.
## 4 Discussion
### Research Uncertainties and Prospects  
In this study, we explored how forest carbon uptake changes with different fragmentation levels and what the main pathway is in which fragmentation affected forest carbon uptake throughout 2000-2018 in forest landscapes in Zhejiang, China. Some uncertainties may exist in our study. Firstly, although forest protection and suspended logging disturbances have been implemented since 2000 in the study area [51; 52], we assumed that the forest coverage was kept stable when the forest loss proportion was less than 5% in the period between 2000 and 2018; this may still induce some uncertainties, since the succession of forests themselves may have caused some changes in forest cover [53]. Secondly, the datasets of forest cover and GPP were produced on a large scale (the whole of China) and have a high accuracy. However, we only used some parts of the datasets, inducing uncertainties in the accuracy of the datasets. Lastly, although the forest fragmentation level classification and GPP estimation were obtained based on certified methods [20; 29; 54], the accuracy of these data may also have some impacts on the study results.
# VIIRS Day/Night Band--Correcting Striping and Nonuniformity over a Very Large Dynamic Range
## 3 Results
### Survey of DNB Imagery
#### 3.1.1 Observations for Daytime Scenes  
Others have observed that daytime VIIRS RSB calibrated radiance scenes exhibit much less striping than MODIS [30; 31], and these artifacts generally are not apparent unless extreme contrast stretching is performed. Since the DNB LGS gain calibration uses the same process as the other RSBs, it would be expected to have similar performance in this regard, but we have found that this is not so. The striping pattern we observed repeats every 16 pixels in the vertical direction, indicating that it is caused by variations in calibration over the 16 DNB detectors. Similar striping is seen symmetrically in the corresponding aggregation zones at the other side of nadir in the scan. In all, striping affects 42% of daytime scenes, and is apparent in 18 of the 32 aggregation zones.
## 4 Analysis of the Stability Strategy of Each Game Subject
### Stability Analysis of Equilibrium Point of Tripartite Evolutionary Game System
It can be seen that when the local government chooses to actively respond, improper allocation of its resources may still lead to the failure of governance, and increasing the degree and effectiveness of active response measures such as public opinion guidance can effectively prevent the public from panic buying. This situation will be reflected in Scenario 3. In Scenario 3: When \((1-\omega_{1})V_{PB}\)<\(C_{P}\) and \(R_{S}^{G}+C_{G}\)<\(R_{G}+R_{U}\), the local government has greater coping costs and its own credibility. At this point, the public's strategy is not panic buying, and the system may have two stable points \(O_{4}(0,0,1)\) and \(O_{6}(1,0,1)\). (a) Ifthe condition \(R_{S}^{G}+C_{S}^{G}\)\(<\)\(C_{S}\) is added, the system only has a unique stable point \(O_{4}(0,0,1)\); (b) If the condition \(C_{S}\)\(<\)\(R_{S}^{G}+C_{S}^{G}\) is added, the system only has a unique stable point \(O_{6}(1,0,1)\). **Proof. ** When \((1-\omega_{1})V_{PB}\)\(<\)\(C_{P}\) and \(R_{S}^{G}+C_{G}\)\(<\)\(R_{G}+R_{U}\), there are \((1-\omega_{1})V_{AB}\)\(<\)\(C_{P}\), \(C_{G}\)\(<\)\(R_{G}+R_{U}+C_{S}^{G}\) and \(-C_{G}^{G}-R_{-U}\)\(<\)\(C_{S}^{G}-C_{G}\); according to Table 4, it can be seen that Conditions 1, 4 and 5 are not satisfied, Conditions 2 and 3 need more conditions to judge; if condition \(R_{S}^{G}+C_{S}^{G}\)\(<\)\(C_{S}\) is added, Condition 2 is satisfied; if condition \(C_{S}\)\(<\)\(R_{S}^{G}+C_{S}^{G}\) is added, Condition 3 is satisfied. \(\square\)  
It can be seen from Scenario 3 that when the local government effectively responds, the sum of central government incentives and positive utility is greater than the sum of its coping costs and subsidies to green smart supply chain enterprises. At this time, if the local government imposes more illegal penalties and positive response subsidies for green smart supply chain enterprises, the strategy portfolio evolution will be stable at (1,0,1). If the local government's illegal penalties and active response subsidies for green smart supply chain enterprises are small, the strategy portfolio evolution will be stable at (0,0,1). Local governments need to ensure that the sum of aggressive subsidies and illegal penalties is strictly greater than their coping costs to avoid a stable strategy mix of (0,0,1). To sum up, \(O_{4}(0,0,1)\), \(O_{6}(1,0,1)\), and \(O_{7}(0,1,1)\) are effective equilibrium points for the three-way evolutionary game system. However, the evolution strategy combination \(O_{6}(1,0,1)\) is an ideal equilibrium point.
# An Overview of Intelligent Transportation Systems in Europe
## 5 Key Features of ITSs
### Measuring the Success and Efficiency of ITSs in Europe  
In Europe, the evaluation of ITSs is based on Key Performance Indicators (KPIs), which are used to assess the efficiency and success of the systems. These KPIs include a thorough analysis of the terminology, calculation methods and types of calculations used in each of the 28 EU countries.  
Figure 8 presents important elements for measuring the success and effectiveness of ITS implementation. These include quantitative and qualitative KPIs; evaluation criteria such as benchmarking and compliance with standards; recommendations for improvements through training and improved data collection; and evaluation issues such as resource limitations and data accuracy.  
A study led by DG MOVE, the European Commission's Directorate-General for Mobility and Transport, found good practices and current applications of the KPIs in the European Union, involving stakeholders through interviews and workshops [74]. Specific ITS KPIs include  
* Reducing travel times;
* Increasing road safety, including reducing the number of crashes and fatalities;
* Optimizing fuel consumption and reducing carbon emissions;
* Increasing the use of public transport and sustainable alternatives.  
Evaluation criteria based on the SMART matrix (Specific, Measurable, Attainable, Relevant and Time-bound) are used to evaluate smart mobility strategies. In order to establish accountability in assessing the effects and success of ITS implementation, this evaluation framework emphasizes the importance of setting concrete and measurable objectives [75]. ITS evaluation includes the following indicators:  
* Output indicators: Immediate data, such as the number of sensors installed or kilometers of smart infrastructure developed;
* Impact indicators: Measuring long-term effects, such as reducing pollution and increasing energy efficiency.
## Appendix C Equations Used for the Preliminary Analysis of the Thermal Subsystem  
The governing equation for this problem can be derived by performing an energy balance on the satellite, considering the incident solar (\(Q_{s}\)), albedo (\(Q_{a}\)), and Earth infrared (\(Q_{e}\)) radiation loads, as well as the radiation exchange with deep space.  
\[mc_{p}\frac{dT}{dt}=Q_{s}+Q_{e}+Q_{a}+\sigma GR_{DS}(T_{DS}^{4}-T^{4}) \tag{1}\]  
Here, \(m\) (kg) is the total mass of the satellite, \(c_{p}\) (\(\rm{J/kg\cdot K}\)) is the effective heat capacity, \(\sigma\) is the Stefan-Boltzmann constant (\(\sigma=5.67\times 10^{-8}\,\rm{W/m^{2}\cdot K^{4}}\)), \(T_{DS}\) (K) is the deep space temperature, \(GR_{DS}\) (\(\rm{m^{-2}}\)) is the radiation exchange factor between deep space and the satellite, and \(T\) (K) is the effective temperature of the satellite [68].  
The information in Table 5 allows the determination of the effective heat capacity, \(c_{p}\), which can be calculated by weighting each individual heat capacity with respect to its mass.  
\[c_{p}=\sum_{i=1}^{n}x_{i}(c_{p})_{i} \tag{10}\]  
The spectral properties of each face of the satellite were calculated considering the fraction of area covered by solar panels. For areas not covered by solar panels, a Kapton film coating was incorporated into the model. This resulted in a determined emissivity of \(\varepsilon=0.65\) and an effective absorptivity of \(\alpha=0.7\) for the satellite's surfaces.
# Design of NO\({}_{2}\) Photoacoustic Detection System Based on Finite Element Simulation
## 1 Introduction
[PERSON] proposed non-contact quartz-enhanced photoacoustic spectroscopy (NC-QEPAS) for trace gas analyses. NC-QEPAS involves putting a synthetic elastic polyxylene film onto the narrow seam of the QEPAS chamber, and through optimizing the coupling effect, the polyylene film resonates with a quartz tuning fork (QTF), and the non-contact photoacoustic detection of gas is realized [21]. Due to its advantages of non-consumption of the gas to be measured, zero background measurements, and high sensitivity, photoacoustic spectroscopy has gradually become one of the popular choices for gas detection [22; 23; 24]. In particular, the use of quartz-enhanced photoacoustic spectroscopy (QEPAS) and photothermal spectroscopy (QEPTS) can result in a high detection limit in a short integration time, but the traditional cylindrical resonant photoacoustic cell has structural advantages in the integration of cavity technology for multi-parameter simultaneous detection, and its price is cheaper than that of a quartz tuning fork. In studies based on first-order longitudinal cylindrical photoacoustic cells, the geometric size of the resonator and buffer cavity directly affect the size of the photoacoustic signal. However, in existing studies, most of the dimensions are directly selected, and few are simulated and analyzed. In view of the complexity of the optimization design process of the photoacoustic cell structure, the processing cycle is long, and the cost is high when multiple samples are compared. In this paper, a finite element analysis software is used to simulate and compare the geometric parameters of a cylindrical photoacoustic cell with cylindrical buffer cavities at both ends, and the optimal structure size is determined according to the laser and the actual processing conditions. At the same time, the working mode of the photoacoustic cell, the sound pressure distribution, and the frequency response curve of the photoacoustic system are simulated and analyzed. Based on the simulation, a NO\({}_{2}\) photoacoustic detection system is established.
# Monocular Vision-Based Depth Estimation of Forward-Looking Scenes for Mobile Platforms
###### Abstract  
The depth estimation of forward-looking scenes is one of the fundamental tasks for an Intelligent Mobile Platform to perceive its surrounding environment. In response to this requirement, this paper proposes a self-supervised monocular depth estimation method that can be utilized across various mobile platforms, including unmanned aerial vehicles (UAVs) and autonomous ground vehicles (AGVs). Building on the foundational framework of _Monodepth2_, we introduce an intermediate module between the encoder and decoder of the depth estimation network to facilitate multiscale fusion of feature maps. Additionally, we integrate the channel attention mechanism ECANet into the depth estimation network to enhance the significance of important channels. Consequently, the proposed method addresses the issue of losing critical features, which can lead to diminished accuracy and robustness. The experiments presented in this paper are conducted on two datasets: _KITTI_, a publicly available dataset collected from real-world environments used to evaluate depth estimation performance for AGV platforms, and _AirSim_, a custom dataset generated using simulation software to assess depth estimation performance for UAV platforms. The experimental results demonstrate that the proposed method can overcome the adverse effects of varying working conditions and accurately perceive detailed depth information in specific regions, such as object edges and targets of different scales. Furthermore, the depth predicted by the proposed method is quantitatively compared with the ground truth depth, and a variety of evaluation metrics confirm that our method exhibits superior inference capability and robustness.  
monocular vision; depth estimation; mobile platform; multiscale feature fusion; attention mechanism +
Footnote †: journal: Applied Sciences