esa-sceva/satcom-chunk-collection huggingface dataset:
# Cost-Effective Satellite Ground Stations in Real-World Development for Space Classrooms
## 5 Design and Development of Satellite Ground Stations
### Equipment of Ground Station
#### 5.2.5. Software Operating with RTL-SDR  
In this research, the SatDump program was chosen to work with RTL-SDR. SatDump is an open-source general-purpose satellite data processing software. The program processes baseband data from the SDR and can decode data from over 90 satellites, such as NOAA 15-18-19, Meteor-M, GOES, Electro-L, Metop, FengYun, etc. It can decode image data  
Figure 10. SDR server: (**a**) SDR server of satellite ground station and (**b**) software diagram on computer.  
from various systems, including Automatic Picture Transmission (APT), Low-Rate Picture Transmission (LRPT), High-Resolution Picture Transmission (HRPT), Low-Rate Information Transmission (LRIT), High-Rate Information Transmission (HRIT), and many more [25].  
In addition to raw image data, SatDump can overlay satellite imagery over a map and produce calibrated and georeferenced L1b products for select satellites, such as sea surface temperature and microphysics, which are suitable for scientific applications like numerical weather forecasts. Moreover, SatDump can decode Inmarsat Aero and STD-C EGC messages, making it an ideal software for learning satellite signal reception.
# Fast and Robust Object Tracking Using Tracking Failure Detection in Kernelized Correlation Filter
## 4 Experimental Results
### Re-Tracking Steps on Tracking Failures  
Figure 12 shows how the proposed method re-capture the target when tracking failure occurred. Figure 12a shows tracking failures in different sequences. The tracking failure is detected and multiple search windows are deployed as shown in Figure 12b. A red search window out of nine neighboring search windows is shown in Figure 12b, which represents the preferred search window. Tracking process in other search windows can be skipped if the target is captured in the preferred search window. In datasets BlurOwl and Coke, there is no advantage of preferred search windows because of irregular movements of the targets. On the other hand in Jogging1, CAU_Ped1, CAU_Ped3 and Tiger2, there are linear movements of the targets so that computational loads could be reduced as the targets were captured in the preferred search windows. As the targets are captured in the preferred search windows or other search windows, tracking is re-started from the corresponding position as shown in Figure 12c.  
Figure 11: Accuracy comparison between the proposed method and original KCF method. **(a)** The proposed method yielded successful tracking while the original KCF based tracker failed. **(b)** Both of the trackers yielded successful tracking. **(c)** Both of the trackers failed.  
Figure 12: Target re-capturing process. (**a**) Tracking failure detected. (**b**) Tracking failure handling. (**c**) Target re-captured.
## 4 Results and Discussion
### Second-Step Optimization - Phenological and Standing Biomass Parameter Estimates
In Reference Model 2, in which the parameters related to phenology were set to the observed values, yearly GPP showed an underestimation of 15.7% for 2002 and 14.1% for 2003, with an improvement compared to Reference Model 1. The error introduced using the internal phenological model is high even using the PROSAILH-BGC with the optimized ecophysiological parameters after first-step optimization (GPPPROSALLH-BGC 1-step); in fact, underestimation of the cumulated annual GPP was -10.4% for 2002 and -11.8% for 2003. The yearly GPP estimated after two-step optimization (GPPPROSALLH-BGC 2-step) showed good accuracy with an underestimation of 1.8% and 5.6% for 2002 and 2003, respectively. These results underline the importance of the phenological parameters in determining the annual GPP budget. Obviously, for application at regional scale, the parameterization of the model with the observed phenology is not operatively feasible. Hence, the proposed method may be considered an important option for determining these parameters. Finally, we evaluated the accuracy of daily GPP modeled by PROSAILH-BGC after two-step optimization. The time courses of daily GPP for 2002 and 2003 are depicted in Figure 6a. Results show good agreement between modeled and observed GPP both at daily (Figure 6b) and yearly (Table 4) time-steps thus underscoring that the proposed approach may be useful in modeling the GPP of poplar plantations. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline _Year_ & _GPP\({}_{measured}\)_ & _GPP\({}_{Reference\ Model\ 1}\)_ & _GPP\({}_{Reference\ Model\ 2}\)_ & _GPP\({}_{PROSALLH-BGC\ 1-step}\)_ & _GPP\({}_{PROSALLH-BGC\ 2-step}\)_ \\ _gC m\({}^{-2}\)yr\({}^{-1}\)_ & _gC m\({}^{-2}\)yr\({}^{-1}\)_ & _gC m\({}^{-2}\)yr\({}^{-1}\)_ & _gC m\({}^{-2}\)yr\({}^{-1}\)_ & _gC m\({}^{-2}\)yr\({}^{-1}\)_ \\ \hline
2002 & 1,578 & 1,253 & 1,330 & 1,414 & 1,550 \\
2003 & 1,473
## 2 Materials and Methods
### General Features of the System
#### 2.4.4 Decrease of Uniformity  
With the results of DUpa for each of the phenological stages and depths used, a dimensionless relationship was obtained that represents the relative variations in DUpa with respect to the control:  
\[\text{DDUpa}=\frac{\text{DUpa}_{\text{y}}-\text{DUpa Control}}{\text{DUpa Control}} \tag{6}\]  
where DUpa\({}_{\text{y}}\): DUpa for a given crop height (y); DUpa control: DUpa for the control condition (with no crop).  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Speed \%** & **15** & **25** & **50** & **100** & & \\ \hline \multicolumn{2}{c}{**Gross Irrigation Depth, mm**} & \multicolumn{1}{c}{**40**} & \multicolumn{1}{c}{**24**} & \multicolumn{1}{c}{**12**} & \multicolumn{1}{c}{**6**} & \\ \hline \multicolumn{5}{c}{**Number of Measurements**} & \multicolumn{1}{c}{**Crop Height, m**} & \multicolumn{1}{c}{**Sprinkler Height, m**} \\ \hline Control & 3 & 3 & 3 & 3 & - & \\ V4 & 1 & 1 & 1 & 1 & 1.2 & \\ V6 & 1 & 1 & 1 & 1 & 1.4 & 1.6 \\ V10 & 1 & 1 & 1 & 1 & 1.55 & \\ R1 BC & 3 & & - & 2.8 & \\ R1 AC & 3 & & & 2.8 & 3 \\ \hline \hline \end{tabular}  
* Phenological development stage of corn [25]; V4- four fully expanded leaves; V6- six fully expanded leaves; V10: ten fully expanded leaves; R1 BC: reproductive stage with sprinklers below the canopy (1.60 m); R1 AC: reproductive stage with sprinklers above the canopy (3 m). Number of catch cans: 94.  
\end{table}
Table 1: Depths evaluated in relation to the phenological stage—crop height—and position of sprinklers.  
Figure 4: (a) Location of catch cans in the crop interrow and (b) control catch cans with no crop.  
Equation (6) was applied for each segment with the average of the four Ids and an average of the entire equipment.  
To confirm the possible effect of sprinkler spacing relative to the uniformity, mean spacing between sprinklers was obtained for each segment and was related to mean DUpa for the four Ids (40, 24, 12 and 6 mm), considering four conditions: (i) Control; (ii) vegetative stage; (iii) reproductive stage with sprinklers below the canopy (R\({}_{1}\)BC) and (iv) reproductive stage with sprinklers above the canopy (R\({}_{1}\)AC).
# Point-Graph Neural Network Based Novel Visual Positioning System for Indoor Navigation
###### Abstract  
Indoor localization is a basic element in location-based services (LBSs), including seamless indoor and outdoor navigation, location-based precision marketing, spatial recognition in robotics, augmented reality, and mixed reality. The popularity of LBSs in the augmented reality and mixed reality fields has increased the demand for a stable and efficient indoor positioning method. However, the problem of indoor visual localization has not been appropriately addressed, owing to the strict trade-off between accuracy and cost. Therefore, we use point cloud and RGB characteristic information for the accurate acquisition of three-dimensional indoor space. The proposed method is a novel visual positioning system (VPS) capable of determining the user's position by matching the pose information of the object estimated by the improved point-graph neural network (GNN) with the pose information label of a voxel database object addressed in predefined voxel units. We evaluated the performance of the proposed system considering a stationary object in indoor space. The results verify that high positioning accuracy and direction estimation can be efficiently achieved. Thus, spatial information of indoor space estimated using the proposed novel VPS can aid in indoor navigation.  
indoor navigation; visual positioning system; graph neural network; point cloud; three-dimensional object pose estimation; voxel +
Footnote †: journal: Applied  
1
## 1 Introduction
Interestingly, after a period of opposition, both from the scientific community and from the media, due to the use of reagents that were toxic to humans or harmful to the environment, chemical methods have experienced a revamping/renaissance [20], thanks to the use of environmentally friendly reagents of natural origin [21], like plant extracts often used as reductants, under the paradigms of environmental sustainability [22]. In this context, the operating conditions for synthesis are milder, even in terms of energy demand, and this is the second aspect that the recent trend lines are inspired by. Aerosol processes have been mainly adopted in NP synthesis where high temperatures are required, as in the case of thermostable NPs produced by spray flame aerosol reactors [23]. Venturi reactors [24] represent a more unusual choice in nanosynthesis, although they have been extensively used in gas adsorption and stripping, due to their advantages in terms of interphase mass transfer. They can be considered as a variant of jet reactors, which have already been proposed in inorganic NP synthesis [25]. A common drawback affecting these methods, relying upon hydrodynamic regimes of precursor mixing, stems from a high particle diameter polydispersity requiring minimisation. To this end, in the present study, a Venturi nozzle is used for the sole purpose of acting as a particle collector, capturing CaCO\({}_{3}\) NP synthesised by mixing two different aerosolised phases, each of them containing one reactant. The novelty of this approach lies in the use of a closed circuit both for gaseous and liquid streams, in order to create both a water- and gas-tight process. As a consequence, such an inherently safer design allows minimising NP dispersion in the environment while also respecting the paradigms of green nanosynthesis. Another key aspect is that this process is carried out at room temperature, achieving the dual benefits of reducing risks to operators and avoiding the energy waste associated with heating precursors. The paper is divided as follows: In Section 2, the utilised reagents and the plant setup are described. In Section 3, the results are discussed and compared with those obtained by different synthesis techniques, including aerosol chemical reactors. In Section 4, the conclusions are drawn and directions for future research are put forward.
## 3 The Proposed Method
### Load Cases  
To cover all the required verifications in the Chinese Design Code, corresponding load and their combination cases were included in the example.  
1. Dead Load (DL). The dead load consisted of the self-weight, the secondary loads, the cable tension forces, and the counterweight in the side span.
2. Vehicle Load (VL). The vehicle loads consisted of uniformly distributed loads (\(q\), 40.2 kN/m) and concentrated loads (\(P\), 1377.1 kN). As simplified static loads, four static load cases with different load layouts were adopted, as shown in Figure 7.
3. Wind Load (WL). The wind speed for the bridge site was 30.1 m/s. Two wind loads with different return periods were imposed as the equivalent static gust wind loads on the main girder, the towers, and the cables, according to the Chinese Design Code. The return period of the design wind speed of WL1 was 10 years, and that of WL2 was 100 years.
4. Load Combination (LCB). A total of 11 different combinations of the dead load, the vehicle load, and the wind load were considered according to the Chinese Design Code.
# Dynamic Tensor Modeling for Missing Data Completion in Electronic Toll Collection Gantry Systems
## 3 Materials and Methods  
### High-Order Tensor Model for ETC Gantry Data  
ETC gantry data on highways exhibit multifaceted characteristics, including complex structural patterns, rapid update frequencies, and varied density values across different data types. To address these complexities, this section introduces a high-order tensor model framework specifically designed for ETC gantry data. This framework aims to filter out attributes that do not pertain to traffic analysis and to streamline the dimensionality of the data. The extraction methodology is depicted in Figure 1.  
In Figure 1, we provide an overview of our proposed high-order tensor model for processing ETC gantry data. The figure illustrates the architecture of the model, which consists of two main components: the high-order tensor model for ETC gantry data on the left and the traffic data calculation process based on the model on the right. The left component encapsulates ETC gantry data in the form of tensor blocks, indicating the multidimensional properties of data collected from various gantry structures. This is further decomposed into subtensor blocks for detailed analysis and processing. The right component shows the sequence of our improved dynamic tensor decomposition model, which starts from a high-order tensor model and is decomposed through dynamic tensor flow decomposition, combined with the Laplace matrix for sp  
Figure 1: Traffic information extraction process for ETC gantry data.  
its climax through the incremental approximate decomposition of the tensor blocks. The interaction between the subtensor blocks and improved dynamic decomposition model is the core of achieving precise traffic data computation, which is the ultimate goal of our research.
## 4 Simulation Analysis
### Vibration Control Effect of Optimally Designed QVIP  
Building upon the established theoretical framework, the QVIP's equilibrium gravity can be effectively tuned through stiffness ratio adjustments (\(\mu\) and \(\
u\)), facilitating load-adaptive optimization. The vibration isolation indicators are defined as follows: Maximum Amplitude refers to the maximum amplitude of the object moving at the equilibrium position, Variance refers to the variance of the object's displacement at the equilibrium position, and Vibration Isolation Efficiency refers to the sum of the percentage reduction in displacement before and after vibration isolation at each moment. Three load cases were investigated: (1) 269.5 N (\(k_{p}=1360\) N/m, \(k_{n}=2000\) N/m), (2) 325.3 N (\(k_{p}=1640\) N/m, \(k_{n}=4000\) N/m), and (3) 389.5 N (\(k_{p}=1960\) N/m, \(k_{n}=6360\) N/m). Figure 11a presents the corresponding theoretical and simulated equivalent nonlinear stiffness forces for these loading conditions. Under a fixed excitation amplitude of 0.009 m, the displacement characteristics are detailed in Figure 11b,c, demonstrating the system's dynamic response across different parametric configurations. Figure 11d presents the three key performance indicators (i.e., peak amplitude reduction, variance reduction and isolation efficiency) evaluating the QVIP's vibration isolation effectiveness under these three operational conditions. The detailed comparison results are provided in Table 1. Simulation results confirm that the QVIP maintains effective vibration isolation performance in terms of all three key indicators under different parameter conditions.
## 1 Introduction
### Review of Alternative Fuels for the Marine Sector
#### 1.2.5 Comparison of Fuels  
Some properties of conventional and alternative marine fuels are presented in Table 1.  
Besides the qualitative indicators shown in Table 1, environmental and economic analyses are crucial for the decision-making process, i.e., choosing the appropriate alternative fuel for a particular ship that operates in a specific area. [PERSON] et al. [62] performed a Life-Cycle Assessment (LCA) and Life-Cycle Cost Assessment (LCCA) of different marine fuels and indicated that among the considered alternatives, fully electrified ships are the most environmentally friendly and cost-efficient alternative to diesel power systems installed on ro-ro passenger ships.  
Recent studies on alternative fuels in the marine sector are presented in Table 2. [PERSON] et al. [22] performed an LCA of Heavy Fuel Oil (IFFO), LNG, LPG, and methanol as marine fuels onboard a Korean bulk carrier. The study indicated that LPG has the lowest GHG emissions, but the country of import significantly affects overall emissions. Similar research was conducted by [PERSON] and [PERSON] [63], who investigated an LCA comparison of Marine Diesel Oil (MDO), LNG, and LBG onboard ro-ro passenger ships. The results showed that the most environmentally friendly option is LBG, whose implementation in the shipping sector would be difficult to achieve without any subsidies. [PERSON] and [PERSON] [64] explored the cost-effectiveness of Low-Sulphur Fuel Oil (LSFO), LNG, and ammonia onboard container ships. Along with capital, investment, and operational costs, carbon cost was also included in the analysis. The study revealed the introduction of carbon allowances into the shipping sector would not be sufficient to replace conventional fuel with ammonia. However, such a tax policy would increase the chance of LNG being more profitable than LSFO.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline  & **Diesel** & **LNG** & **LPG** & **Methanol** & **DME** & **Hydrogen** & **Ammonia** \\ \hline LHV (MJ/kg) & 42.5 & 46–50.2 & 46.3 & 20 & 28.8 & 120 & 18.6 \\ \hline Density (kg/m\({}^{3}\)) & 833–881 & 450 & 500.5 & 798 & 667 & 0.0838 & 682.3 \\ \hline Carbon content (\%) & \(>\)85 & 75 & 82.6 & 38 & 52 & 0 & 0 \\ \hline Flashpoint (\({}^{\circ}\)C) & 52–96 & \(-\)136 & 470 & 11 & 235 & - & 132 \\ \hline Boiling point (\({}^{\circ}\)C) & 163–399 & \(-\)160 & \(-\)42 & 64.5 & \(-\)25 & \(-\)253 & \(-\)33 \\ \hline Cetane rating & \(>\)40 & 0 & - & \(<\)5 & \(<\)55 & - & - \\ \hline \end{tabular}
\end{table}
Table 1: Comparison of different marine fuels [58; 59; 60; 61].
###### Abstract  
Tunable laser spectroscopy (TLS) with infrared (IR) imaging is a powerful tool for gas leak detection. This study focuses on direct absorption spectroscopy (DAS) that utilizes wavelength modulation to extract gas information. A tunable interband cascade laser (ICL) with an optical power of 5 mW is periodically modulated by a sawtooth injection current at 10 Hz across the methane absorption around 3271 nm. A fast and sensitive thermal imaging camera for the mid-infrared range between 3 and 5.7 \(\upmu\)m is operated at a frame rate of 470 Hz. Offline processing of image stacks is performed using different algorithms (DAS-F, DAS-f and DAS-2f) based on the Lambert-Beer law and the HITRAN database. These algorithms analyze various features of gas absorption, such as area (F), peak (f) and second derivative (2f) of the absorbance. The methane concentration in ppm*m is determined on a pixel-by-pixel analysis without calibration. Leak localization for methane leak rates as low as 0.25 mL/min is accurately displayed in a single concentration image with pixelwise sensitivities of approximately 1 ppm*m in a laboratory environment. Concentration image sequences represent the spatiotemporal dynamics of a gas plume with high contrast. The DAS-2f concept demonstrates promising characteristics, including accuracy, precision, 1/f noise rejection, simplicity and computational efficiency, expanding the applications of DAS.  
tunable laser spectroscopy; mid-infrared imaging; direct absorption spectroscopy; DAS-2f; gas leak detection; gas imaging +
Footnote †: journal: Applied Sciences
# Secure Encapsulation Schemes Using Key Recovery System in IoMT Environments
## 2 Related Work
### Secret Sharing  
Secret sharing schemes are ideal for sensitive information. These pieces of information should kept highly confidential, as their exposure could be disastrous. However, it is also critical that they should not be lost. Traditional encryption schemes are not suitable for achieving a high level of confidentiality and stability at the same time. When storing encryption keys, the user has to choose between keeping a single copy of the key in one location or multiple copies of the key in multiple locations for maximum security. The secret sharing scheme proposed by [PERSON] and [PERSON] [18; 19] in 1979 is a scheme of dividing the secret value into several pieces so that the secret value can be recovered only when more than a certain number of pieces are collected. Such a scheme is called [PERSON]'s (k, n) threshold scheme. This scheme divides the secret value into n pieces and entities may recover the secret value only when more than k pieces are collected. In another type of secret sharing scheme, there is one dealer and n players. The dealer gives a share of the secret to the players, but only when specific conditions are fulfilled will the players reconstruct the secret from their shares. The dealer accomplishes this by giving each player a share so that any group of t (for threshold) or more players can together reconstruct the secret but no group of fewer than t players can. In addition, many other secret sharing schemes have been proposed throughout the years with as in the care of signcryption, each of them having its problems and limitations while offering different levels of security and computational costs [20; 21].
## 3 Material and Methods
### SIS UREs Assessment  
After removing invalid and abnormal broadcast navigation messages, six-year BDS nominal SIS UREs were evaluated. Three indicators were adopted for the SIS UREs assessment: Orbit-only URE, global average URE, and worst-case URE [20].  
The orbit-only URE is an assessment of the average URE over the entire earth surface. It only considers the orbit error as shown in Equations (1) and (2) with various coefficients for the MEO and IGSO/GEO satellites, respectively  
\[\mathit{Orbit-only}\ \mathrm{URE}_{MEO}=\sqrt{\left(0.98R\right)^{2}+\frac{1}{54} \big{(}A^{2}+C^{2}\big{)}}, \tag{1}\]  
\[\mathit{Orbit-only}\ \mathrm{URE}_{IGSO/GEO}=\sqrt{\left(0.99R\right)^{2}+ \frac{1}{127}\big{(}A^{2}+C^{2}\big{)}}, \tag{2}\]  
where \(R\) represents the radial component error, \(A\) represents the along-track component error, and \(C\) represents the cross-track component error.  
The global-average URE is another average URE assessment indicator that takes both orbit and clock error into consideration. Similar to the orbit-only URE, various satellite orbital altitudes result in different coefficient as shown in Equations (3) and (4)  
\[\mathit{Global-average}\ \mathrm{URE}_{MEO}=\sqrt{\left(0.98R-T\right)^{2}+ \frac{1}{54}\big{(}A^{2}+C^{2}\big{)}} \tag{3}\]  
\[\mathit{Global-average}\ \mathrm{URE}_{IGSO/GEO}=\sqrt{\left(0.99R-T\right)^{2}+ \frac{1}{127}\big{(}A^{2}+C^{2}\big{)}} \tag{4}\]  
where \(T\) represents the satellite clock error.  
The worst-case URE is a third assessment criterion for an instantaneous URE. It describes the maximum instantaneous URE for a user in the satellite coverage. Both orbit and clock errors are considered in Equation (5)  
\[\mathit{Worst-case}\ \mathrm{URE}=\max_{|\theta|\leq\gamma}(R\cos\theta-T+ \sqrt{A^{2}+C^{2}}\sin\theta) \tag{5}\]  
where \(\theta\) is the satellite off-nadir angle and \(\gamma\) is the maximum off-nadir angle within the satellite coverage.
## 7 Comparative Analysis  
ASC-RL was experimented with and compared with other schemes to ensure its authenticity and efficiency. ASC-RL was compared to CAS-IIoT-RL [22], LSTM-RL [27], and AEM-RL [28] for various metrics. These experiments are described in more detail in the following sections.