esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results
### Theoretical Model
#### 3.3.1 Transient Response
\begin{split} R(t)=\bigg{\{}K_{air}\bigg{(}1-e^{-\frac{t}{\tau_{ air}}-(t_{0}+nT)}\bigg{)}u(t-t_{0}-nT)+R_{air}(0)\ air\ \frac{K_{PG}}{\tau_{PG}}e^{-\frac{t}{\tau_{PG}}-(t_{0}+\frac{T}{2}(2n+1))}u \Big{(}t-t_{0}-\frac{T}{2}(2n+1)\Big{)}\\ +R_{PG}(0)\ \text{\it propane gas}\end{split}  \tag{22}\]  
From Figure 2a, \(t_{0}\) is the delay time due to the stabilization of the sensor and instruments, \(T\) is the exposure period of the sensor and \(n=1,\ 2,\ \ldots\), indicates the sensing cycle. For the first period, the time was between 848.48 and 1410.2 s, \(n=1\), \(t_{0}=848.48\ s\), \(T=561.72\ s\), \(R_{air}(0)=659.134\) K\(\Omega\), \(R_{PG}(0)=655.59\) K\(\Omega\), \(K_{air}=865.92\ K\), \(\frac{K_{PG}}{\tau_{PG}}=867.672\ K\), \(\tau_{air}=89.21\ s\), and \(\tau_{PG}=47.8\ s\):  
\[R(t)= \begin{cases}865.92\times 10^{3}\Big{(}1-e^{-(\frac{t}{92.21}+848.48)} \Big{)}u(t-848.48)+659.13\times 10^{3}&848.48<t<1129.34\\ 867.672\times 10^{3}e^{-(\frac{t}{7.8}+1129.34)}u(t-1129.34)+655.59\times 10^{3}&1129.34<t< 1410.2\end{cases}  \tag{23}\]  
Figure 3 shows a graph of expression (23) where the experimental data were considered. From Figure 3, the theoretical result was close to the experimental measurements when the sensor detected air and propane gas. The minor variations can be attributed to experimental errors, system noise, or contamination in the measurement chamber. Figure 3: Theoretical and experimental sensing results of the ZnAl\({}_{2}\)O\({}_{4}\).
## 3 Analytical Expressions for Vortex Beams Formed with Binary Axicons
### Vortex Beams behind Binary Axicon  
In [26], the authors used binary phase axicons similar to that shown in Figure 1b to form Bessel beams of the first and second orders in the terahertz range. The cross-section of one of these beams, which was recorded using a microbolometer array detector, is shown in Figure 3. In [26], it was shown analytically that the electric field of a wave at a distance \(z^{\prime}\) behind the axicon can be written in the paraxial approximation as  
\[E(z^{\prime},\rho,\theta)=\frac{4k}{\pi z^{\prime}}(-i)^{\ell}e^{ik(z^{\prime }+\rho^{2}/2z^{\prime})}\times\int_{0}^{a}I_{\ell}\left(\frac{k}{z^{\prime}}r^{ \prime}\rho\right)\sin[(\kappa r^{\prime}-\ell\theta)]e^{ikr^{\prime 2}/2z^{ \prime}}r^{\prime}dr^{\prime}. \tag{13}\]  
Hereinafter, we use the coordinate system shown in Figure 2. We employed the polar coordinates \((r^{\prime},\varphi)\) for the axicon plane and the coordinates \((\rho,\theta)\) in the space behind the axicon and in the lens plane. The upper limit of the integral is the axicon radius \(a\).  
As shown above, the region of existence of quasi-Bessel beams is determined by expression (11). A simplified analytical expression for the electric field of the Bessel beam was derived from (13) for the region \(a<<z<z_{A}\) (\(z_{A}=ka/\kappa\)):  
\[E(z^{\prime},\rho,\theta)\propto\frac{2\kappa}{\pi}(-i)^{\ell-1}\sqrt{\frac{2 \pi iz^{\prime}}{k}}e^{i\theta+ik(z^{\prime}+\rho^{2}/2z^{\prime})-i\kappa^{2 }z^{\prime}/2k}I_{\ell}(\kappa\rho), \tag{14}\]  
and for the intensity:  
\[I(z^{\prime},\rho,\theta)\approx J_{\ell}^{2}(\kappa\rho)\frac{8\kappa^{2}z^{ \prime}}{\pi k}. \tag{15}\]  
Figure 3: Image of a quasi-Bessel beam formed with a binary axicon and recorded by a microbolometer detector array (compare with Figure 1e). Right: sequence of video frames demonstrating firing paper with this beam. In this case, no polarization converter was used, and the beam had linear polarization. Frame dimensions were \(16.32\times 12.24\) mm\({}^{2}\).  
Figure 2: Optical system for launching vortex surface plasmon polaritons on a cylindrical conductor.  
One can see that the cross-section of the beam intensity exactly corresponds to the Bessel function. The analytical calculations in [19] were finished on this expression, and further results were obtained using numerical simulations and experiments. Since in this work, we are interested in the excitation of plasmons by means of diffraction of radiation on an end face of a cylindrical conductor, it is useful to derive, as an intermediate stage, analytical expressions for beams illuminating such a conductor. In the next section, we will find analytical expressions for converting beams described by expression (13) using a lens. Since the lens diameter is approximately equal to the axicon radius \(a\), which is much larger than the diameter of the first rings of the Bessel beam, in the further calculations, we used expression (13), which does not contain further simplifications, as an initial expression for the wave illuminating the lens.
## 3 Results
### Performance of the PMLv2 and MODIS Products in eWUE Estimations
However, the MODIS product for soybean produced better estimates than that for maize for all the GPP, ET, and eWUE at an annual scale, as indicated by the RMSE and Bias reducing from 834.74 g C m\({}^{-2}\) year\({}^{-1}\) and \(-\)799.7 g C m\({}^{-2}\) year\({}^{-1}\), 126.80 mm year\({}^{-1}\) and \(-\)76.97 mm year\({}^{-1}\), 1.30 g C Kg\({}^{-1}\) H\({}_{2}\)O and \(-\)1.18 g C Kg\({}^{-1}\) H\({}_{2}\)O for soybean to 195.85 g C m\({}^{-2}\) year\({}^{-1}\) and \(-\)48.7 g C m\({}^{-2}\) year\({}^{-1}\), 83.31 mm year\({}^{-1}\) and \(-\)34.07 mm year\({}^{-1}\), 0.29 g C Kg\({}^{-1}\) H\({}_{2}\)O and 0 g C Kg\({}^{-1}\) H\({}_{2}\)O for maize, respectively. Figure 8: Scatter plots of the annual observed and RS-based GPP, ET, and eWUE at the five cropland sites from the PMLv2 products (**left**) and MODIS products (**right**) for C4 maize and C3 soybean. The PMLv2 eWUE was calculated as the ratio of GPP and ET from the PMLv2 product. The MODIS eWUE was calculated as the ratio of GPP from the MOD17 product and ET from the MOD16 product.
# Research on Dynamic Modeling and Transition Flight Strategy of VTOL UAV
## 5 Flight Strategy Calculation Case
### The X Axis Open-Loop Rapid Transition  
Considering the influence of dynamic characteristics, the VTOL UAV can reach the transition terminal window with different control methods. The induced aerodynamic force has very low sensitivity to the overall deflection of the induction device and can only change the direction of its force. However, the induced aerodynamic force is very sensitive to the induced wing deflection, which is manifested in the direction change and the non-linear change of the induced aerodynamic force.
## 6 Single-Factor Influence Analysis and Optimization of the Split-Stream Rushing Exhaust Muffler  
### Analysis of the Single-Factor Influence  
#### 6.1.1 Wall Thickness  
Before performing the single-factor influence analysis on transmission loss considering sound-structure coupling, the value of the muffler wall thickness, a critical structural parameter, must be established. Belonging to the category of thin-walled structures, the muffler features wall thickness as a crucial design parameter. Variations in this parameter not only directly impact the structural rigidity but also exert significant effects on the muffler's eigenfrequencies and the characteristics of acoustic wave propagation [35]. Typically, augmenting the wall thickness results in an elevation of the muffler's eigenfrequencies, consequently altering the acoustic field distribution.  
Figure 20 presents a comparative analysis of the eigenfrequencies of structural modes and sound-structure coupled modes concerning their order for three distinct muffler wall thicknesses. Considering that the upper frequency of interest in this study is 4000 Hz, an auxiliary line was incorporated to facilitate analysis. As shown in Figure 20a, the frequency of structural modes of identical order exhibits an upward trend with increasing wall thickness, and the magnitude of the frequency increase also progressively increases with higher modal orders. This indicates that augmenting the wall thickness results in an elevation of the eigenfrequencies for structural modes and sound-structure coupled modes of an identical order.  
Figure 19: Frequency–sound pressure graph of the split-stream rushing muffler (2). (**a**) Without the acoustic–structure coupling effect (3510 Hz), (**b**) With the acoustic–structure coupling effect (3500 Hz).  
Figure 21 presents the transmission loss characteristics for three distinct wall thicknesses. As shown in Figure 21, variations in wall thickness exert a minimal influence on the transmission loss characteristics of the shunt gas counterflow muffler. The three transmission loss curves exhibit a largely consistent overall trend, with discrepancies primarily localized at the peak values and within certain frequency ranges. This phenomenon indicates that the influence of the wall thickness on transmission loss is contingent upon the synergistic effects of other parameters and does not exhibit a monotonic trend of either an increase or decrease. Considering the peak transmission loss characteristics across varying wall thicknesses, a value of 2 mm was ultimately selected for the muffler wall thickness in the ensuing structural parameter optimization.
## 4 Discussion
### Future Research Directions  
Three-dimensional printing allows for greater accuracy in reconstruction and offers less invasive and more customizable operating procedures. These factors have the potential to improve outcomes in terms of function and morbidity, streamlining treatment, rehabilitation and care procedures, and improve prognoses. Thus, 3D printing may become the standard of healthcare in the future.  
The time needed for designing, manufacturing, and using a 3D-printed personalized medical device (including an implant) continue to decrease as both engineers and medical specialists gain experience. For the aforementioned reasons, it is crucial to establish efficient interactions and trust between the corresponding members of an interdisciplinary team [6].  
The next frontier of personalized 3D-printed medicine is implantable devices tailored to the needs of patients. [PERSON] et al. [7] proposed a strategy for the selective laser sintering (SLS) of medical devices adapted to patients for the production of an airway support device (tracheal and bronchial implants restoring airway patency to pediatric patients diagnosed with tracheal and bronchial softening). This procedure is in line with the FDA's 2018 recommended additive manufacturing guidelines for medical devices and includes medical image-based modeling, input analysis, design verification, material verification, device verification, and device validation, including validation as a template for the quality control of personalized 3D-printed implants [7].  
Further development opportunities for the described group of exoskeletons include the implementation of principles in accordance with the Pre-Industry 4.0 paradigm, including technical control at every stage of production and the analysis of the product life cycle until its recycling or disposal [33; 34; 35; 36]. These developments will be facilitated not only by the more widespread use of artificial intelligence and the industrial Internet of Things but also by new methods for signal acquisition, including directly from the central nervous system [37; 38].  
Robotic rehabilitation with the use of exoskeletons undoubtedly offers greater therapeutic possibilities than current treatment options, including increased and more precise control of the dose of therapy [39; 40; 41]. Personalized 3D-printed exoskeletons extend these possibilities even further. However, the development of this technology must be controlled, including relevant research, indications, and contraindications, as well as clinical guidelines.  
In exoskeleton research, effectiveness counts. A review by [PERSON] et al. (2018) indicated as many as 45 prototypes of soft exoskeletons for the hand, while to the best of our knowledge, in 2022, none of these exoskeletons are yet on the commercial market [42].
# Quasi-Consensus of Disturbed Nonlinear Multiagent Systems with Event-Triggered Impulsive Control
## 2 Preliminaries and Model Description  
### Graph Theory  
In MASs, the communication among agents can be reflected by the graph. Each agent can be seen as a node, and let \(V=\{v_{1},v_{2},\ldots,v_{N}\}\) be the node set. Let \(E\subseteq V\times V\) be the edge set, and the undirected topology of MASs can be described by the graph \(G=(V,E,C)\), where \(C=[a_{ij}]_{N\times N}\) represents the adjacency matrix of \(G\). If \((i,j)\
otin E\), it means that agents \(i\) and \(j\) do not communicate with each other, there are \(a_{ij}=a_{ji}=0\), otherwise \(a_{ij}=a_{ji}=1\). Additionally, define \(a_{ii}=0\). \(D=\operatorname{diag}(d_{1},d_{2},\ldots,d_{N})\) is defined as the degree matrix of \(G\), where \(d_{i}=\sum_{i=1,j\
eq i}^{N}a_{ij}\). \(L=[l_{ij}]_{N\times N}\) is called the Laplacian matrix of \(G\) and \(L=D-C\). The communication state between leader and followers are represented by a matrix \(B=\operatorname{diag}(b_{1},b_{2},\ldots,b_{N})\). If the follower can communicate with the leader, then \(b_{i}=1\), otherwise \(b_{i}=0\). We call \(N_{i}:=\{j|a_{ij}>0\}\) the neighbor set of agent \(i\). Let \(H=L+B\). \(N_{i}\) is defined as the set of agents that communicate with the agent \(i\). If a node can reach any nodes in the graph, then the node is called the root, and the graph has a spanning tree with the root.
## 5 Simulation and Experimental Results
### Experimental Model
#### 5.3.1 System Model Dynamics  
Dynamic equations of a system were derived using the formulation of Euler-Lagrange. Considering that the end-point deflection angle is minimal, this is estimated by \(\alpha=\frac{D}{L}\), where \(D\) is the link end-point displacement, and the length of the link is \(L\). For modeling the flexible link, the 2 nd order rotary system model is considered in this experimentation. The one end of the link turns around, and the other stays fixed. The simplified, flexible link manipulator model is obtained in [39], and by computing Lagrangian and later using the Euler-Lagrange equation, the flexible link manipulator dynamic equations are given by (40) and (41).  
\[\ddot{\theta}=\frac{T_{l}}{I_{eq}}-\frac{B_{eq}\dot{\theta}}{J_{eq}}+\frac{K_{ stiff}\alpha}{J_{eq}} \tag{40}\]  
\[\ddot{\alpha}=-K_{ stiff}\bigg{(}\frac{1}{I_{eq}}+\frac{1}{I_{link}}\bigg{)} \alpha+\frac{B_{eq}}{J_{eq}}\dot{\theta}-\frac{T_{l}}{I_{eq}} \tag{41}\]  
Defining states as \(x_{1}=\theta\), \(x_{2}=\alpha\), \(x_{3}=\dot{\theta}\), \(x_{4}=\dot{\alpha}\), and \(V_{m}=u\), the states representation of Equations (40) and (41) are described as per [33] given as (42).  
\[\left.\begin{array}{l}\dot{x}_{1}=x_{3}\\ \dot{x}_{2}=x_{4}\\ \dot{x}_{3}=936.39x_{2}-41.19x_{3}+72.4593u\\ \dot{x}_{4}=-1372.6x_{2}+41.19x_{3}-72.4593u\end{array}\right\} \tag{42}\]  
The control problem is to synthesize EGESO based sliding mode law for controlling the servo motor deflection (\(\theta\)) as well as end-point deflection (\(\alpha\)), which is considered as a mismatched uncertainty in the first channel of (42). The experimental setup is shown in Figure 9.
## 4 Discussion  
### Interpretation of Findings  
From the analysis of the results presented in this study, carbon emissions increased from 2010 to 2015, followed by a slight decline from 2015 to 2020. This trend is consistent with the findings of [PERSON], [PERSON] et al. regarding carbon emissions in Hebei Province [43]. This change indicates that the implementation of the \"2014-2015 Energy Conservation and Emission Reduction Low-Carbon Development Action Plan\" in Hebei Province has achieved results. It reflects that the research area has responded to the call of Hebei Province and has begun to see the effects of a series of measures taken in energy conservation, emission reduction, industrial structure adjustment, and ecological protection.  
The results of the carbon footprint pressure index reveal the severe situation of current carbon emissions. The data show that there are relatively few counties in a carbon balance zone, with most counties in a carbon imbalance zone, and the proportion of counties in the imbalance zone has increased over time. This indicates a significant carbon footprint risk, which is consistent with the results described in the analysis of carbon footprints in Chinese cities, particularly in Hebei Province [44].  
The zoning results of carbon emission risk indicate an upward trend in carbon emission risk, which aligns with the findings of [PERSON], [PERSON] et al. [34]. Through the above analysis, it is evident that the research area continues to face the severe challenge of increasing carbon emission risk from land use.  
Figure 6: Cluster map of cold and hot spots of carbon emission risk.
###### Abstract  
CHAMP and Swarm satellite magnetic data are combined to establish the lithospheric magnetic field over the Tibetan Plateau at satellite altitude by using zonal revised spherical cap harmonic analysis (R-SCHA). These data are integrated with geological structures data to analyze the relationship between magnetic anomaly signals and large-scale geological tectonic over the Tibetan Plateau and to explore the active tectonic region based on the angle of the magnetic anomaly. Results show that the model fitting error is small for a layer 250-500 km high, and the RMSE of the horizontal and radial geomagnetic components is better than 0.3 nT. The proposed model can accurately describe medium- to long-scale lithospheric magnetic anomalies. Analysis indicates that a negative magnetic anomaly in the Tibetan Plateau significantly differs with a positive magnetic anomaly in the surrounding area, and the boundary of the positive and negative regions is generally consistent with the geological tectonic boundary in the plateau region. Significant differences exist between the basement structures of the hinterland of the plateau and the surrounding area. The magnetic anomaly in the Central and Western Tibetan Plateau shows an east-west trend, which is identical to the direction of the geological structures. The magnetic anomaly in the eastern part is arc-shaped and extends along the northeast direction. Its direction is significantly different from the trend of the geological structures. The strongest negative anomaly is located in the Himalaya block, with a central strength of up to \(-9\) nT at a height of 300 km. The presence of a strong negative anomaly implies that the Curie isotherm in this area is relatively shallow and deep geological tectonic activity may exist.  
L +
Footnote †: journal: Sensors  
17238  
1
Footnote 1: institutetext: School of Geodesy and Geomatics, Wuhan University, 129 Luoyu Road, Wuhan 430079, China; [EMAIL_ADDRESS] (Y.Q.); [EMAIL_ADDRESS] (Z.W.); [EMAIL_ADDRESS] (B.Z.); [EMAIL_ADDRESS] (F.L.); [EMAIL_ADDRESS] (F.G.)
## 3 Current Signal Processing and Feature Extraction
### Characteristic Processing of High-Frequency Current Signal
#### 3.1.4 Margin Indicators  
The margin index \(L_{f}\) is defined as the ratio of signal peak to root mean square amplitude, and the calculation formula is:  
\[L_{f}=\frac{x_{\max}}{x_{\tau}}=\frac{\max[x_{\tau}(\tau)]}{(\frac{1}{N}\sum \limits_{i=1}^{N}\sqrt{|x_{i}|})^{2}} \tag{4}\]  
In the formula, \(x_{\tau}\) is the root amplitude of the signal.
# Helmholtz Coils Based WPT Coupling Analysis of Temporal Interference Electrical Stimulation System
###### Abstract  
Electrical nerve stimulation (ENS) is clinically important in treating neurological diseases. This paper proposes a novel temporally interfering wireless power transfer (WPT) system, based on Helmholtz coils, to address energy depletion and the miniaturization of wireless power transfer systems for implantable devices. Compared to conventional WPT systems, this paper uses Helmholtz coils with a centrosymmetric structure as the transmitting coils. A more uniform and stable magnetic field was obtained through structural improvements. It also improves the problem that changes in the receiving coil's position affect the transmission power's stability. Based on the principle of temporal interference (TI), two transmitting coils with a slight frequency difference generate a superposition of magnetic fields on the receiving coil and then induce a low-frequency electrical signal on it. The electrical stimulation system applies stimulation parameters of a specific intensity and frequency directly to the target nerve with electrodes connected to it. This eliminates the need for the conventional high-frequency signal to low-frequency signal processing circuitry and reduces the device's size. In this paper, numerical calculations and an experimental verification of the proposed system are carried out. The magnetic field distribution and the receiving coil current waveform of the system were tested to verify the effectiveness and stability of the proposed design. The experimental results showed that the proposed wireless power transfer system can generate electrical signals of the desired waveform in the receiving coil. Its frequency of 10 Hz and amplitude of 42.4 mA meet the requirements for the electrical stimulation of the sciatic nerve.  
wireless power transfer (WPT); Helmholtz coils; temporal interference (TI); electrical nerve stimulation (ENS); sciatic nerve; complex regional pain syndrome type I
## 5 Discussion
### Natural and Touchscreen Interactions  
Our study initially found that user satisfaction with AR-based audio interaction is superior to touchscreen interfaces. While this finding aligns with established knowledge about the immersive benefits of HMDs, we further contextualized our results by comparing them with existing literature on HMD-based audio interactions in AR.  
Existing studies, such as those by [PERSON] et al. [30] and [PERSON] and [PERSON] [22], have extensively documented the immersive audio experiences provided by HMDs. These studies highlight how HMDs can enhance spatial audio perception and user engagement in virtual environments. However, our study contributes to this body of knowledge by focusing specifically on the accessibility of AR for users with visual impairments, an area that has been less explored.  
In comparison with other advanced AR interfaces, our audio-based non-visual interface offers the following unique advantages.  
Spatial Audio Techniques: While existing studies often emphasize visual enhancements in AR, our research underscores the importance of sophisticated audio rendering techniques, such as varying sound volumes to indicate the proximity and orientation of virtual objects. This method provides users with an intuitive understanding of spatial relationships within the AR environment, which is crucial for users with visual impairments.  
User Engagement and Satisfaction: Our findings indicate a significant preference for audio-based natural interaction over traditional touchscreen interfaces. This preference suggests that users find the audio cues more intuitive and engaging, aligning with results from studies like those by [PERSON] and [PERSON] [21], which also emphasize the benefits of spatial audio in enhancing user experience.  
By comparing our study with existing literature, we highlight the unique contributions of our approach in creating a more inclusive and immersive AR experience. Our discussion demonstrates that while the benefits of HMDs are well documented, our specific focus on audio-based non-visual interfaces for accessibility sets our research apart and advances the field of AR technology.