esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Internal Contact Pressure Model Validation
### Validation for Wire Bending Model
Another crucial factor influencing the interaction forces between wires is the axial tension in the cable. As Figure 20a,b shows, there is a positive correlation between the contact stress among wires and cable tension. It can be inferred that in stay cables with higher tension, the frictional force between the wires is correspondingly greater. This also explains why slippage occurs later in cables with higher tension. The fluctuation in the force between wires affects the difference in contact stress among different layers of wires. A smaller fluctuation in force results in a lesser distribution of force to the inner layers of wires, reducing the loss of contact pressure during transmission and minimizing the difference between layers. If the fluctuation in force is considered a parameter related to the position of the wires, utilizing Markov chain and Taylor series expansion could provide a means to uncover the diffusion pathways of contact pressure among wires within the  
Figure 20: The relationship between contact stress in different layers and the curvature of the wire: (**a**) \(\mathrm{T}=20,000\) N, \(\omega=1/3\); (**b**) \(\mathrm{T}=10,000\) N, \(\omega=1/3\); (**c**) \(\mathrm{T}=10,000\) N, \(\omega=1/4\); (**d**) \(\mathrm{T}=10,000\) N, \(\omega=1/5\). cable. This approach would offer a more comprehensive understanding of the slippage dynamics between wires.
## 4 Simulation Verification
### Simulation of Bilateral Load Change
Although the proposed control strategy demonstrates good performance in simulations, there are several challenges in real-world deployment that should be considered. First, an accurate estimation of AC frequency and DC voltage deviations is essential, requiring reliable sensing and filtering. Second, while the strategy itself does not require inter-subsystem communication, coordination with other control layers (e.g., economic dispatch) may involve communication links that must be robust. Third, the controller needs to be implemented on embedded hardware with sufficient speed and precision; while DSP or FPGA platforms are adequate, limited hardware in low-cost systems may pose constraints. These issues highlight the importance of further experimental validation under practical conditions. The scalability of the proposed control strategy is also an important consideration. Since adaptive droop control is a decentralized method based on local measurements of frequency and voltage deviations, it is inherently scalable to larger systems with multiple interlinking converters (ILCs) and distributed generation (DG) units. Each ILC operates independently without relying on global communication, which simplifies integration as the microgrid expands. However, in extremely large-scale systems, coordination at a higher control layer (e.g., tertiary control) may be required to maintain system-wide optimization. Future work will focus on validating the proposed method in more complex topologies. The accuracy of the proposed control strategy in regulating frequency and voltage has been verified through quantitative simulation comparisons. As shown in Figures 11-14 and Table 3, the proposed method consistently achieves lower frequency and voltage deviations compared to the conventional droop control approach, indicating higher control precision under various load conditions.
# Vertical-Type Ni/GaN UV Photodetectors Fabricated on Free-Standing GaN Substrates
## 1 Introduction  
Ultraviolet (UV) detection is widely demanded in different applications, such as environmental monitoring systems, flame monitoring, gas detection, or medical inspection systems [1]. The III-V nitride semiconductors, with a tunable direct bandgap (3.4 eV for GaN and 6.2 eV for AlN), good chemical and thermal stability, and radiation hardness, are highly promising for the fabrication of photodetectors in UV regions [2; 3]. Different structures for GaN-based detectors have been reported, including the Schottky-type, metal-semiconductor-metal (MSM) structures, \(p\)-\(i\)-\(n\) diodes and avalanche types [4; 5; 6; 7]. Among them, Schottky-type photodetectors exhibit the merits of fast response speeds, low-level noises, and self-powered operation, which are attractive for UV detection in remote or extreme conditions. Early Schottky-type GaN UV photodetectors were mainly fabricated on foreign substrates, such as sapphire or Si, and high-density surface states with native disordered oxides or vacancies exist on the GaN layers. The surface states lead to a low Schottky barrier height (SBH) and high leakage currents due to the Fermi-level pining effect, which greatly degrades the device responsivity and reliability [8; 9].  
Recently, the rapid progress on free-standing GaN substrates offers a good opportunity for the fabrication of high-performance vertical-type opto-electronic devices. A total threading dislocation density (TDD) lower than \(10^{6}\)/cm\({}^{2}\) has been obtained for commercialized GaN substrates. The homoepitaxial growth and properties of GaN-on-GaN have been investigated by our group.  
The surface state density as low as \(\sim\)10\({}^{11}\) cm\({}^{-2}\)eV\({}^{-1}\) in the metal-oxide-semiconductor structures were obtained by the two-step pre-treatments [10]. Nearly ideal Schottky barrier diodes with an ideality factor close to unity were also achieved on GaN epilayers grown on GaN substrates with optimized growth rates [11]. However, there is no report on the photo-response properties of vertical-type detectors fabricated on free-standing GaN substrates. In this study, vertical-type Schottky photodetectors on GaN-on-GaN are fabricated with 5-nm-thick Ni as the Schottky contact. The electrical and photo-response properties are characterized by analyzing the carrier transport mechanisms across metal/semiconductor interfaces. The photodetector shows a good spectra selectivity between UV and visible light, and a high detectivity, even at zero voltage. The effects of growth rate in the GaN epilayers on the performance of the photodetectors are also illustrated.
# Co-Efficient Vector Based Differential Distributed Quasi-Orthogonal Space Time Frequency Coding
## 2 Distributed Space-Time-Frequency Coding
### Space Time Frequency Coding at the Source Node  
The cooperative system is based on OFDM modulation with \(N\) sub-carriers and \(T\) OFDM time slots. At the source node, a stream of \(NT\) modulated symbols, \(\mathbf{s}=[s(0),s(1),\ldots,s(NT-1)]\), are generated from an \(MPSK\) constellation. The \(NT\) symbols are simultaneously distributed across \(n=0,1,\ldots,N-1\) sub-carriers and \(t=0,1,\ldots,T-1\) OFDM time slots. In the frequency dimension, the \(N\) sub-carriers are grouped into \(K=\lfloor N/N_{b}\rfloor\) blocks. Similarly, in the temporal dimension, the \(T\) OFDM time slots are grouped into \(K=\lfloor T/T_{b}\rfloor\) blocks. Thus, each \(k_{th}\) block, \(k=1,2,\ldots,K\) is of length \(\Gamma=N_{b}T_{b}\), where \(N_{b}\) and \(T_{b}\) denote the number of frequency sub-carriers and time slots, respectively, per block. Based on this, the coded source node data is constructed:  
\[\mathbf{x}=[x(0),x(1),\ldots,x(NT-1)]=\left[\mathbf{x}_{1}^{T},\mathbf{x}_{2}^{T},\ldots,\bm {x}_{K}^{T},\mathbf{0}_{NT-KP\Gamma}^{T}\right]^{T} \tag{1}\]  
where \(\mathbf{x}_{k}=[x_{k}(1),\ldots,x_{k}(P\Gamma)]^{T}\in\mathbb{C}^{P\times 1}\) and \((NT-KP\Gamma)\) zeros are padded into \(\mathbf{x}\) if \(NT\) is not an integer multiple of \(KP\Gamma\). The coded source node data can be viewed as a concatenation of information symbols in the temporal and frequency dimensions since the elements of \(\mathbf{x}_{k}\) are stacked simultaneously into \(PN_{b}\) adjacent data sub-carriers and \(PT_{b}\) OFDM time slots. Assuming the system is perfectly synchronized in the time and frequency domains, the \(P\Gamma\times 1\) data vector transmitted by the source node in the \(k\)th block can be written as \(\mathbf{x}_{k}=[x_{k,t,n}(1),\ldots,x_{k,t,n}(P\Gamma)]^{T}\in\mathbb{C}^{P\Gamma \times 1}\), where \(x_{k,t,n}(i),i=1,2,\ldots,P\Gamma\) denotes the \(i\)th symbol transmitted on the \(n_{th}\) sub-carrier within the \(t_{th}\) OFDM time slot. Since the source node transmits the data vector \(\mathbf{x}_{k}\) to \(P\) relay nodes simultaneously across \(PT_{b}\) OFDM time slots and \(PN_{b}\) frequency sub-carriers, then the source node code is capable of achieving a diversity of order \(\Gamma=N_{b}T_{b}\) at each relay node. The criteria for achieving this diversity order will be clarified further on in this paper. The elements of \(\mathbf{x}\) are normalized such that \(E\left(\left|\mathbf{x}_{k}\right|^{2}\right)=1\).
# A Reflection-Type Dual-Band Phase Shifter with an Independently Tunable Phase
## 2 Design Method of Proposed Dual-Band Phase Shifter
### Analysis of Phase Shifting Range  
Figure 3 shows the equivalent circuits at \(f_{\rm L}\) and \(f_{\rm H}\). With the exception of the series TL, none of the elements affect the PSR. By compensating for the parasitic effects of \(\lambda/4\) shunt open stubs using (3) and (6), the proposed dual-band PS can achieve a PSR nearly identical to that obtained when a single alone varactor diode is used. The following sections discuss PSRs in each operating band.
## 3 Results and Discussion
### Thermal Weightlessness Performance Analysis  
The thermal resistance of DT was evaluated using a TGA-Q500 thermogravimetric analyzer. The weight loss of tackifier DT occurs in four stages. In the first stage, DT experiences a weight loss of 6.64% at approximately 100 \({}^{\circ}\)C, primarily due to the evaporation of a small amount of free water in the product. In the second stage, the mass loss of DT is 1.16% between 100 \({}^{\circ}\)C and 229 \({}^{\circ}\)C, likely resulting from the loss of bound water. In the third stage, the mass loss reaches 15.67% between 229 \({}^{\circ}\)C and 354 \({}^{\circ}\)C, primarily due to the thermal decomposition of the amide groups in the product. In the fourth stage, the mass loss of DT is 51.15% between 354 \({}^{\circ}\)C and 480 \({}^{\circ}\)C, primarily attributed to the thermal decomposition of the main chain. In summary, tackifier DT demonstrates good thermal stability, as illustrated in Figure 4.  
Figure 3: 1H-NMR diagram of the tackifier.
# High-Pressure Sensors Based on Laser-Manufactured Sintered Silicon Carbide
###### Abstract  
In this work Sintered Silicon Carbide (S-SiC) samples have been used to fabricate fiber-optic-coupled pressure sensors. The sensor structure reproduces a low-finesse Fabry-Perot (FP) interferometer. Laser manufacturing of cylindrical S-SiC samples was performed to define the thin membrane geometry of sensors. FP cavity is defined by the end-face of a single mode fiber and the S-SiC diaphragm surface. Hence, pressure is evaluated by measuring the cavity depth by a dedicated optoelectronic system coupled to the single mode fiber. Exploiting the excellent properties of S-SiC, in terms of high hardness, low thermal expansion, and high thermal conductivity, realized devices have been characterized up to 20 MPa. Experimental results demonstrate that produced sensors exhibit a non-linearity around \(\pm\)0.6%F.S. and a high input dynamics. The all-optic sensing system proposed in this work would represent a good alternative to conventional solutions based on piezoelectric effects, overcoming the drawback related to electromagnetic interference on the acquired signals. In addition, the mechanical characteristics of S-SiC allow the use of the sensor in both automotive and aerospace hostile environments as pressure monitors in combustion engines.  
F a 4 September 2020; Accepted: 10 October 2020; Published: 13 October 2020
## 3 Wave Head Calibration Based on Parameter Optimization MVMD and Morphological Gradient
### Traveling Wave Characteristic Signal Extraction Based on MPA-Optimized MVMD  
According to the basic principle of MVMD, when using MVMD to decompose line-mode voltage and zero-mode voltage, it is necessary to set the number of intrinsic mode functions \(K\) and penalty factor \(\alpha\) in advance. \(K\) and \(\alpha\) determine the accuracy and bandwidth of modal decomposition, which directly affects the extraction effect of traveling wave characteristic signals. At present, it is common to set two core parameters based on human experience, but the randomness and uncertainty of human setting will inevitably have a certain impact on the correctness of MVMD results. Through multiple iterations, MPA gradually converges to the optimal solution, that is, the predator position with the highest fitness, so as to realize the search and optimization of the core parameters. In this paper, the optimal number of modes \(\hat{K}\) and penalty factors \(\hat{\alpha}\) of MVMD are obtained by MPA. The specific optimization steps are shown in Figure 2.  
The MPA fitness function is constructed based on minimizing the comprehensive entropy kurtosis ratio of both line-mode and zero-mode traveling waves, as expressed in Formula (16).  
\[\langle\hat{K},\hat{\alpha}\rangle=\text{argmin}_{(K,\alpha)}\left\{\sum_{c} \min_{\{x_{c}\}}\left\{\frac{H_{Pm}}{k_{m}-3}\right\}\right\} \tag{16}\]  
Within this formula, \(\text{argmin}_{(K,\alpha)}\left(\cdot\right)\) yields the parameter values corresponding to the function's minimum value, with \(\hat{K}\) and \(\hat{\alpha}\) representing the optimal parameter. \(x_{c}(t)\) denotes the combined set of line-mode and zero-mode voltage signals. The permutation entropy value of the \(m\)th traveling wave intrinsic mode function component is represented by \(H_{Pm}\), while \(k_{m}\) indicates the kurtosis value of the \(m\)th intrinsic mode function component.  
Formula (16) demonstrates that the fitness function, founded on minimizing the comprehensive entropy kurtosis ratio, enables MVMD to simultaneously decompose both  
Figure 2: MPA-optimized MVMD flow chart.  
line-mode and zero-mode voltage signals while targeting the extraction of traveling wave characteristic signals that contain the most significant wave information and minimal noise components.  
Subsequently, the IMF component exhibiting the lowest entropy/kurtosis ratio among all IMFs from line-mode voltage decomposition is defined as the line-mode traveling wave characteristic signal. Similarly, the IMF with the minimum entropy/kurtosis ratio from zero-mode voltage decomposition is defined as the zero-mode traveling wave characteristic signal, thus completing the extraction of the traveling wave characteristic signals.
# Topology and Response Surface Optimization of a Bicycle Crank Arm with Multiple Load Cases
## 3 Results and Discussion
### Topology Optimization Result
#### 3.1.3 Effect of Stress Constraint  
The mass optimization result with two cases of stress constraints can be seen in Figure 11. It shows the optimized crank arm with stress constraints of 80% and 90% yield strength. In terms of topological holes, the difference between the two cases is considerably small. Both have two large horizontal holes in the middle of the body and two small holes close to the pedal hole. The maximum stress obtained from both cranks is 92.0 and 133.6 MPa, respectively. The obtained stress value is lower than the constraint due to the smoothening and rounding process for the topological hole during geometry creation.  
From the above two optimization parameters, i.e., compliance and mass, it is then interesting to inspect the overall optimization performance by objective functions, as well as mesh refinement. For comparison purposes, the coarse model of 48,020 elements is optimized in the same manner. In the fine model, the number of elements is 677,089, as previously indicated. Table 4 shows the compliance comparison among the selected models. This is beneficial to observe whether a coarser mesh provides a significant impact on the compliance value, as well as the topological holes pattern. The sample from compliance minimization with 50% and 60% mass constraint and sample from mass minimization with 80% and 90% stress constraint are used for observation. From the table, the sample with 50% and 60% mass constraint (compliance minimization) has similar compliance values between the coarse and fine mesh. Similarly, the sample with an 80%-90% stress constraint (mass minimization) also has identical compliance value. This shows that for those samples, even though the topological holes obtained from the optimization process is not identical (as seen in Figure 12), that does not seem to bring much different changes in the optimized compliance value or the obtained mass.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multirow{2}{*}{**Sample**} & \multicolumn{2}{c}{**Final Mass (kg)**} & \multicolumn{2}{c}{**Compliance (J)**} & \multicolumn{2}{c}{**Stress (MPa)**} \\ \cline{3-8}  & & **Coarse Mesh** & **Fine Mesh** & **Coarse Mesh** & **Fine Mesh** & **Coarse Mesh** & **Fine Mesh** \\ \hline \multirow{3}{*}{Compliance Minimization} & 50\% Mass constraint & 0.15 & 0.15 & 0.0002 & 0.00021 & 68.27 & 91.09 \\ \cline{2-8}  & 60\% Mass constraint & 0.18 & 0.19 & 0.0002 & 0.00021 & 57.63 & 85.01 \\ \cline{2-8}  & 80\% Stress Constraint & 0.17 & 0.16 & 0.0003 & 0.0003 & 64.8 & 92.0 \\ \cline{2-8}  & 90\% Stress Constraint & 0.16 & 0.15 & 0.0007 & 0.00069 & 66.7 & 133.6 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Compliance comparison between coarse and fine mesh model.  
Figure 11: Effect of stress constraint in mass minimization: (**a**) 80% yield strength, (**b**) 90% yield strength.
###### Abstract  
This paper presents a novel 3D Gaussian Splatting (3 DGS)-based Simultaneous Localization and Mapping (SLAM) system that integrates Light Detection and Ranging (LiDAR) and vision data to enhance dynamic scene tracking and reconstruction. Existing 3 DGS systems face challenges in sensor fusion and handling dynamic objects. To address these, we introduce a hybrid uncertainty-based 3D segmentation method that leverages uncertainty estimation and 3D object detection, effectively removing dynamic points and improving static map reconstruction. Our system also employs a sliding window-based keyframe fusion strategy that reduces computational load while maintaining accuracy. By incorporating a novel dynamic rendering loss function and pruning techniques, we suppress artifacts such as ghosting and ensure real-time operation in complex environments. Extensive experiments show that our system outperforms existing methods in dynamic object removal and overall reconstruction quality. The key innovations of our work lie in its integration of hybrid uncertainty-based segmentation, dynamic rendering loss functions, and an optimized sliding window strategy, which collectively enhance robustness and efficiency in dynamic scene reconstruction. This approach offers a promising solution for real-time robotic applications, including autonomous navigation and augmented reality.  
3D reconstruction; 3D Gaussian Splatting; scene understanding; sensors fusion Article The 3D Gaussian Splatting SLAM System for Dynamic Scenes Based on LiDAR Point Clouds and Vision Fusion  
[PERSON], [PERSON], and [PERSON] (2020), 15, 4190.
## 4 Objectives and Hypothesis  
The general objective of this paper is to propose a process work for the virtual retrieval of the architectural structures, features and mural paintings of these dilapidated historic buildings using classical and other novelty tools, so these buildings digitally reconstructed can then be displayed in a virtual environment for the enjoyment of all. One of the works detailed in this paper is to produce a digital restoration of the eighteenth century murals that once adorned the St Augustine church in San Cristobal de La Laguna for reintegrating them within a virtual model of the church. Currently the church is quite literally in ruins, and its murals almost entirely lost, which means that the recovery efforts involved in this digital reconstruction project are very much about restoring both, the building and its pictorial issues, to their former glory. It should be noted that in reviewing the scientific literature there were no records of papers studying the use of DStretch(r) to recover murals. Consequently, the authors of this paper decided to propose a work process that guarantees the trustworthy digital reconstruction of the church.  
To reach this objective, a practical case study was designed in which the following specific objectives were set:  
* Obtain a virtual reconstruction of the building through classical methodology (planimetric survey by topography and photogrammetry) to represent graphically its structures, its features and its materials, both indoor and outdoor. For the digital processing and recovery of frescos in the altar and presbytery of St Augustine church:
* Propose the methodological process for digital image analysis using DStretch(r) to recover hidden motifs invisible to the naked eye.  
Figure 1: Current state of disrepair of the St Augustine church.  
* Recover paintings and drawings that are invisible to the naked eye from the altar and the presbytery using DStretch(r) digital image processing, image analysis and antique photograph records.
* Obtain a digital restoration of mural paintings.
* Include the digital restorations of the mural paintings in the 3D virtual model of the church. For virtual interaction with the building:
* Create an interactive model that can be viewed using a (HMD) virtual reality headset that allows the user to interact with supplementary information in this virtual environment.  
In light of these objectives, the following hypothesis has been formed: \"As a piece of digital image analysis software DStretch(r) is useful for recovering obscured artwork from worn and eroded murals\".  
If this hypothesis is confirmed in this work, DStretch(r) could be considered to be a tool for the digital reconstruction of murals and frescos. The contribution made to innovation would be the expansion of available methodologies for studying dilapidated murals.