esa-sceva/satcom-chunk-collection huggingface dataset:
# Denoising Directional Room Impulse Responses with Spatially Anisotropic Late Reverberation Tails
## 2 Stochastic Model for Anisotropic Late Reverberation
### Spatial Incoherence under an Arbitrary Power Distribution  
The spatial coherence function between two incident directions \(\Omega\) and \(\Omega^{\prime}\) is defined as  
\[\gamma(f,t)_{\Omega,\Omega^{\prime}}=\frac{\Psi(f,t)_{\Omega,\Omega^{\prime}} }{\sqrt{\Psi(f,t)_{\Omega,\Omega}\Psi(f,t)_{\Omega^{\prime},\Omega^{\prime}} }}, \tag{6}\]  
where \(\Psi(f,t)_{\Omega,\Omega}\) and \(\Psi(f,t)_{\Omega,\Omega^{\prime}}\) are, respectively, the auto- and cross-power spectral densities (PSD):  
\[\Psi(f,t)_{\Omega,\Omega^{\prime}}=\mathrm{E}\left\{x(f,\Omega,t)x^{*}(f, \Omega^{\prime},t)\right\}. \tag{7}\]  
For the signal model in Equation (1), this gives a cross-PSD of  
\[\Psi(f,t)_{\Omega,\Omega^{\prime}}=P(f,\Omega,t)\delta_{\Omega,\Omega^{ \prime}}, \tag{8}\]  
leading to a spatial coherence of  
\[\gamma(f,t)_{\Omega,\Omega^{\prime}}=\delta_{\Omega,\Omega^{\prime}}, \tag{9}\]  
a value independent of whether the uncorrelated plane wave field has a direction-dependent power distribution or not. In the SHD, however, the result only holds for a spatially isotropic field [18], which gives a coherence of \(\widetilde{\gamma}(f,t)_{n,n^{\prime}}=\delta_{l,l^{\prime}}\delta_{m,m^{ \prime}}\) between SH components (with component index \(n=l^{2}+l+m\)). In general, an anisotropic distribution will deviate from this result with nonzero cross-component coherence, even though the original plane wave field may be incoherent (see Section 3.1 below). The fact that this characteristic coherence result can only be derived in the SHD for an isotropic field implies that SHD-based measures of spatial coherence (such as those proposed by [PERSON] et al. [18], for example) are unadapted to the analysis of anisotropic cases.
## 6 Precise Orbit Determination Methods
### High-Precision Orbit Prediction Methods for Space Targets at Long-Distance  
With the rapid escalation in the quantity of spacecrafts and space debris, the responsibilities of space situational awareness systems are undergoing a substantial surge in complexity. A critical focal point for advancing these systems lies in the development of algorithms for orbit determination that are not only more robust but also more efficient and accurate. This becomes especially challenging given the constraints posed by the limited number of space situational awareness platforms and their detection capabilities. Tackling these challenges is indispensable for realizing the precise and prompt tracking of distant space targets, thereby forming the linchpin for future endeavors in space collision prevention.
# Target Image Mask Correction Based on Skeleton Divergence
## 4 Conclusions  
This study was conducted to model and process discrete pixels in complex images. We proposed a binary mask correction model based on skeleton divergence of the source and mask images. Discrete pixel region edges were extracted with bilateral filtering, edge smoothing was performed, and the skeleton of the global discrete pixel region was extracted. The skeleton was then used as the center of local mask correction to optimize edge gradients and achieve region merging. The TOPSIS method [15] was used to determine the ideal merge strategy, and additional point-cloud regularization constraint verification was adopted. The mask-correction effect of the proposed algorithm in both single-objective and multi-target cases was tested experimentally and compared with four other high-quality processing algorithms. The effectiveness of the proposed algorithm was verified using various discrete source images of ranging complexity, with our results indicating that it outperformed all the other algorithms. One shortcoming of this approach is that a fixed-value method was adopted in the setting of the scatter length optimization step of the skeleton model. This resulted in a lack of flexibility and should be the subject of further research. Nonetheless, this highly robust algorithm presents a promising option for use in image-processing applications.  
Conceptualization, Z.X. and W.H.; Methodology, Z.X. and Y.W.; Software, Z.X.; Validation, Y.H.; Formal analysis, Z.X. and W.H.; Investigation, Z.X. and Y.W.; Writing--original draft preparation, Z.X.; Writing--review and editing, Z.X. and W.H.; Funding acquisition, Y.W., Y.H. and M.J.  
This research was supported by the Natural Science Foundation of Zhejiang Province (LZ20F020003, LY17F020034, LS219F010001), the National Natural Science Foundation of China (61272311, 61672466), and the 521 Project of Zhejiang Sci-Tech University.  
Thanks for the test data set provided by researchers at the Technical University of Munich, Germany.  
The authors declare no conflict of interest.
# Design and SAR Analysis of a Dual Band Wearable Antenna for WLAN Applications
## 2 Design Methodology
### Metamaterial Based Approach  
Metamaterials are artificially-designed materials that are used as a ground plane to enhance the performance of an antenna. These materials offer suppression of surface waves at intended frequency bands, thereby offering improvements in efficiency, gain, directivity and other parameters of an antenna. The design of two different unit cells of the two different EBG structures to be employed as a ground plane for the designed dual band wearable antenna is outlined in the section below.
# Towards Online Estimation of Human Joint Muscular Torque with a Lower Limb Exoskeleton Robot
## 2 Methods
### Sensing System Design  
A sensing system was designed to measure all signals required by the proposed IDA, including the posture of the trunk (\(B\)), the acceleration of hip joints (\(O_{1}\) and \(O_{2}\)), the angular displacement/velocity/acceleration of the hip and knee joints, and the foot contact forces (FCF).  
To avoid misalignment of the sensor and user discomfort, the motion information of the human body is not measured directly by mounting sensors on the human body. Instead, the entire sensing system is embedded into the exoskeleton structure to get the motion information about the exoskeleton. Then, according to the motion mapping from the exoskeleton to the human model, the user's motion data are derived. The motion mapping is ensured by the structural design, the description of which can be found in Ref. [30]. The sensing system is described below.
# Networked Microgrids: A Review on Configuration, Operation, and Control Strategies
## 2 Networked Microgrids' Configuration
### Formation
#### 2.1.2 Graph Theory Approaches  
Graphs, as a specialized data structure, serve as an abstraction for real-world power grids, allowing the visualization and solution of distributed grid problems using graph theory and algorithms. The mapping of electrical networks to graph concepts establishes a connection between network components and vertices, and between connections and edges in the graph. This translation allows for the exploration of intelligent algorithms in solving electrical network problems, proving valuable in the segmentation of distribution networks into multi-microgrids [21]. In power distribution networks, graph-based concepts such asgraph partitioning, spanning tree, and spanning forest are utilized to create microgrids, incorporating both loop-based microgrid topology (as in [22; 23]), and radial-based microgrid topology (as in [18; 19; 20]).  
Two key graph-theory-based methods for forming NMGs are minimum spanning tree (MST) algorithms and breadth-first search (BFS) trees. MST algorithms aim to create a tree encompassing all nodes in a network while minimizing total edge weight. In power systems, each DER is represented as a node in a graph, where edges denote potential connections between DERs. The primary goal of MST is to identify the minimum set of edges required to connect all nodes (DERs) efficiently, without forming cycles. In [20; 24], this application is used to maximize critical load while adhering to radial topology and operational constraints such as power balance, voltage, and current limits.  
Breadth-first search (BFS) is a traversal and search algorithm applied to tree or graph data structures. In the context of forming NMGs' topology, BFS uses a generator bus as the root node, initiating the exploration of adjacent nodes at the present depth before moving on to nodes at the next depth level. This process results in a BFS tree, where each MG extends like a tree by selecting adjacent buses based on their ascending electrical distance from the root. In [19; 25; 26], this topology is formulated with the aim of maximizing load restoration, taking into account considerations of criticality and operational constraints.
## 3 Materials and Methods
### Research Methods  
The study uses SEM to examine the impact of emerging digital technologies on SDG progress in European Union countries. SEM allows for the simultaneous evaluation of direct and indirect relationships between digital technologies, economic performance, and SDG progress. This method combines factor analysis and regression analysis [71], providing a detailed perspective on how components of DESI influence SDG progress.  
Direct relationships represent the immediate effects of one variable on another without any intermediary influence. For instance, the direct relationship between the Digital Economy and Society Index (DESI) and SDG progress highlights how improvements in digital public services, human capital, and digital technology integration can directly contribute to sustainable development outcomes.  
Indirect relationships, on the other hand, capture the mediated effects where one variable influences another through an intermediary variable. In this study, economic performance, measured as GDP per capita, acts as a mediator. The indirect relationship quantifies how digital technology adoption first impacts economic performance, subsequently affecting SDG progress. By incorporating both direct and indirect effects, the research provides a holistic understanding of the pathways through which digital technologies contribute towards achieving sustainability goals.  
This dual perspective is essential to uncovering the complex interactions and dependencies within the digitalization and sustainability framework. SEM enables the testing of the two research hypotheses while quantifying these mediated effects, offering insights into both the immediate and long-term influences of digitalization on sustainable development.  
Figure 1 illustrates the research model of digital influences on sustainability and the mediating role of economic performance.  
\begin{table}
\begin{tabular}{c c c c} \hline
**Variable** & **Data Sets** & **Measures** & **Sources** \\ \hline DPS & Digital public services & Score & [68] \\ HC & Human capital & Score & [68] \\ IDT & Integration of digital technology & Score & [68] \\ SDGi & SDG Index Score & Aggregate score (0 to 100) & [69] \\ SDG1–SDG17 & Goal 1–Goal 17 & Score (0 to 100) & [69] \\ GDPc & GDP per capita in PPS & Purchasing power parities (PPPs) & [70] \\ \hline \end{tabular} Source: developed by authors based on [68; 69; 70].  
\end{table}
Table 1: Selected variables.
## 2 Classification of Compression Garments and Specific Requirements  
Compression textile products may be defined as compression products for a special purpose that could be medicine [2, 3], sport [4, 5, 6, 7] or body formation purposes [8]. There are a number of well-known commercial brands such as Sigvaris (Switzerland), Orlman (Spain), Otto Bock (Germany), Bauerfeind (Germany) and others in the world market of orthopaedic compression supports. The main attention is given to the compression properties of these products; however, aesthetic, comfort and end-use properties are not less important for consumers. The analysis of textiles for medical applications indicated that there are different classifications of these groups. Firstly, medical and preventive supports, or compression garments may be classified by the position of the human body (Table 1). Classification according to the position on the body is essential for primary identification. However, the most important is the classification of medical textiles according to their purpose or special function. Compression garments generate compression to a particular body part. Compression may be defined as the normal force acting on a body in the perpendicular direction of the applied tensile force [9]. Recent medical compression garments are individually designed and manufactured for a particular part of the body: medical compression stockings for vascular diseases, compression bodysuits, face masks, medical orthopaedic supports, prevention compression supports, etc. (Table 2). All of these products have the same explicit purpose of compression; however, the variety of these function applications is wide [10]. \begin{table}
\begin{tabular}{l l} \hline \hline  & **Body Part** & **Position of Support** \\ \hline \multirow{3}{*}{Arm} & \begin{tabular}{l} Wrist \\ Elbow \\ Shoulder \\ \end{tabular} \\ \hline \multirow{3}{*}{Leg} & \
\begin{tabular}{l} Tarsus/ankle \\ Knee \\ Hip \\ \end{tabular} \\ \hline \multirow{2}{*}{Other} &
\begin{tabular}{l} Belly (pregnancy) \\ Back/waist \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Classification of orthopaedic supports according to the position on the body. Compression garments are beneficial for the recovery of several markers of exercise-induced muscle damage, accelerate recovery of muscle function, and may also assist athletes following exercise, but the findings are often isolated or inconclusive [21; 22]. However, it is proven that some kind of compression sportswear may affect muscle performance or
## 3 Adsorption of Model Compounds by Eggshell Biocomposite Adsorbents
### Temperature Effects and Thermodynamic Parameters
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Pollutant** & \multirow{2}{*}{**Conventional Adsorbents**} & \multirow{2}{*}{\(q_{e}\) **(mg/g)**} & **Ref.** \\ \cline{3-4}
**Ions and Dyes** & & & \\ \hline \multirow{2}{*}{MB dye} & Tea activated carbon (TAC) & 24.9–433 & [115] \\ \cline{2-4}  & Cocont shell-derived hydrochar & 187.7 & [116] \\ \hline \multirow{4}{*}{RBV 5 dye} & Sawdust-based AC & 453.0 & [117] \\ \cline{2-4}  & Coal-based AC & 201.1 & [117] \\ \cline{2-4}  & Cocoa pod husk-based AC & 13.0 & [118] \\ \hline \multirow{2}{*}{Methyl red dye} & Sepiolite & 70.8 & [119] \\ \cline{2-4}  & AC & 78.3 & [119] \\ \hline Reactive yellow dye & Rice husk AC & 5000 & [120] \\ \hline \multirow{4}{*}{CR dye} & Carbon nanotubes & 500 & [121] \\ \cline{2-4}  & Activated carbon (AC) & 312.5 & [121] \\ \cline{2-4}  & Guava peel activated carbon & 120.6 & [122] \\ \cline{2-4}  & Commercial activated carbon (CAC) & 71.4 & [123] \\ \hline \multirow{4}{*}{RhB dye} & Geopolymer coal gangue & 0.77–1.0 & [124] \\ \cline{2-4}  & Activated sugar-based carbon & 123.5 & [125] \\ \cline{2-4}  & Activated carbon from Gmelina & \multirow{2}{*}{1000} & [118] \\ \cline{2-4}  & aborea leaves & & \\ \hline \multirow{2}{*}{Cu\({}^{2+}\)} & chitosan-montmorillonite & \multirow{2}{*}{87.0} & [126] \\ \cline{2-4}  & composite aerogel & & \\ \cline{2-4}  & Diphenylcarbazide chitosan hydrogel & 185.5 & [127] \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Conventional adsorbents used to remove selected ionic and dye pollutants.
## 3 Results and Discussion  
The proposed method was implemented in Matlab (R2020b) on a system with a 64-bit Windows operating system, 16 GB memory, and a 2.9 GHz Intel i5 processor. Initially, the plant region was segmented from the plant images using Algorithm 1. Once the noise region was removed from the plant region, these images were given as input to the transfer learning models and the proposed model.
# Emergency Repair Scheduling Model for Road Network Integrating Rescheduling Feature
## 1 Introduction
Repair activity execution involves the possession of repair resources and the determination of the available quantity of all usable repair resources. Therefore, an emergency repair scheduling problem handled by maintenance units during the response phase is essentially a good application to the RCPSP, in which the decision maker schedules all repair works and integrates the resources of various crew and engineering equipment to conduct the emergency operation. The conceptual idea of this model starts with identifying the damaged road sections to obtain preliminary data from the first strike of disaster, and then, the decision maker can determine the demand for all kinds of repair resources based on the target time to recover the damage of the whole road network. Based on the initial assessment of damage status, the proposed model then establishes the first emergency repair schedule for the road network. When the second-wave hazard events come, new disaster points will be generated, and the new damage status needs to be updated. Those unexpected events force the decision maker to make a corresponding decision for the adjustment to fulfill the new repair needs. Under such dynamic circumstances, this study intends to provide a rescheduling feature to rearrange all existing repair activities adjusted to the new condition after second-wave hazard events. The following section gives a review of the major contributions in the literature on emergency repair scheduling of the road network and the resource-constrained project scheduling problem (RCPSP). Section 3 presents the conceptual idea and model formulation of the proposed model. Section 4 provides two cases and four scenarios to demonstrate the application of the proposed model. Finally, Section 5 concludes research contributions and future works.
# Secure and Lightweight Cloud-Assisted Video Reporting Protocol over 5G-Enabled Vehicular Networks
## 4 Overview of Proposed Protocol
### Security Objectives  
The proposed protocol is designed to satisfy the following security requirements.  
* Authentication and Authorization: Any vehicle has to be authenticated before it can send (report) a video recorded by its camera.
* Identity privacy preservation: The real identity of every vehicle should be protected from being known by other vehicles, RSC, DVs and DMV.
* Fine-grained access control: ABE should guarantee a fine-grained access control by which a designated vehicle should strictly be capable to recover a video fitting to its possessed access structure.
* Non-repudiation: A given vehicle should not deny its participation in video reporting.
* Traceability: TA should be capable of disclosing the real identity of all the entities in the system.  
Figure 1: System Architecture.
# First In-Orbit Validation of Interferometric GNSS-R Altimetry: Mission Overview and Initial Results
## 4 Discussion  
Unlike traditional altimeters, iGNSS-R offers wide-swath coverage, exceeding even SWOT's swath width. However, its observations contain gaps due to limited beam counts. This study's validation payload tracked up to four beams simultaneously, but geometric analysis suggests that 14-15 satellites could be tracked at 35\({}^{\circ}\) incidence by expanding the beam capacity. Combined with iGNSS-R's low-cost advantage, multi-satellite constellations could further enhance spatial coverage. Based on the simulation results in Section 2.3, the iGNSS-R system achieves an average spatial resolution of 9 km for GPS and 5 km for BDS/Galileo within 35\({}^{\circ}\) incidence angles, comparable to Jason-3 and Sentinel-6's low-resolution mode (LRM), though inferior to Sentinel-6's SAR mode and SWOT. Nevertheless, this successful in-orbit validation demonstrates iGNSS-R's potential for high-resolution (5-10 km) ocean remote sensing products (e.g., sea surface height, wind speed, and significant wave height).  
Preliminary assessments using Jason-3 and Sentinel-6 data showed that the iGNSS-R altimeter achieves an SSH accuracy of 17.2 cm@40 km, which is a breakthrough for GNSS-R altimetry. Notably, current operational GNSS-R missions (e.g., CYGNSS, Spire) remain constrained to meter-level altimetry accuracy, due to their inherent reliance on narrow-bandwidth local code correlation processing schemes [10, 17, 18, 19, 20, 21]. However, when equivalently scaled to 5 km along-track smoothing, the altimetric error of the iGNSS-R altimeter is about 48.65 cm, which is over an order of magnitude higher than that of conventional radar altimeters. In the future, further improvements in accuracy and synergistic use with existing altimeters require deeper study.  
Compared with the SSH RMSE, error contributions from tides, DAC, and tropospheric delays are minor. The impacts of ionospheric delay and sea state bias require further validation, due to the current lack of reliable in situ reference data. While quantitative assessments of sea state bias and ionospheric errors are not addressed here, instrument noise and speckle errors--which directly degrade interferometric waveform quality--are the dominant error sources [51, 52, 53, 54, 55]. These errors exhibit strong dependencies on the GNSS constellation, signal frequency, bandwidth, incident angle, SNR, PRN code, and so on [56, 57, 58]. Given the complexity of these relationships, a detailed analysis will be presented in a subsequent study.
## 5 Conclusions  
This paper proposed a novel adaptive control scheme utilizing TDE and RL for the angular position tracking control of robotic manipulators. The proposed control scheme can achieve a good tracking accuracy and a fast tracking performance even when subject to the system uncertainty and unknown disturbance. Moreover, the angular position and angular velocity of each joint of the manipulator are guaranteed to be within their preset constraints. The boundness of tracking errors and the stability of the robotic system controlled by the proposed controller are proven by Lyapunov theory. Notably, the stability will not be breached by the RL trying some bad action candidates, which ensures a safe environment for RL to explore the optimal policy. Simulation results validate the effectiveness of the proposed control scheme.  
Z.X.: Conceptualization, data curation, writing original draft. Q.L.: Formal analysis. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The author agrees to publication.  
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.  
The authors declare that there are no conflict of interest regarding the publication of this paper.  
Figure 18: Parameter \(\hat{d}_{i}\) handling TDE errors in case 2: Joint 1 (blue solid line). Joint 2 (orange solid line).
# The Ground-Based Absolute Radiometric Calibration of the Landsat 9 Operational Land Imager
## 3 Data
### RadCaTS  
A summary of the satellite ephemeris for Landsat 9 at Railroad Valley is shown in Table 2, which describes the collection area of the ground site, the typical overpass time, and the satellite view geometry. There were 38 Landsat 9 daytime overpasses at the RadCaTS during the period from November 2021 to June 2023, with 12 being considered successful. The typical reasons for an unsuccessful collection are clouds at the site or water/snow on the test site surface. The current quality assurance (QA) criteria for an overpass at the RadCaTS is similar to what was developed for the RadCalNet [110]. The QA criteria are founded on a well-understood uncertainty budget and include the 550 nm AOD as well as the average surface reflectance for each of the eight GVR channels to account for surface nonuniformities.