esa-sceva/satcom-chunk-collection huggingface dataset:
# Decomposition of Multicomponent Micro-Doppler Signals Based on HHT-AMD
## 4 Simulation Studies and Performance Evaluation
### Selection of the Dimidiate Frequency and Searching Step Length  
As aforementioned analysis in Section 3.4, the search range, dimidiate frequency and search step play important roles in the HHT-AMD process. In order to investigate the influence of these parameters on the algorithm, the simulated signals \(s(t)=\exp(-j10\sin(20\pi t))+\exp(-j20\cos(25\pi t))+n(t)\) are used here. After HHT, we get the cursory components of the signals. Based on the decomposition results by HHT, the frequency range of the search is set to be \(5\pi\)\(\sim\)\(50\pi\) initially for the signals. We choose a set of step lengths [1; 2; 3; 4; 5] and the dimidiate frequency is set to be 25 initially. The search step length should be determined according to the frequency range. The larger step length may be used firstly, and then the small step length is used during searching process gradually. Dynamic simulations are tested for different combination of the three parameters, respectively.  
The relationship of these parameters is utilized to analyze the performance of HHT-AMD. The results of the measurements are shown in Table 1. It is clear that the different parameter selections lead to different results of decomposition. Generally, large search range is applied at first, and it tends smaller during the process. The dimidiate frequency should be modified according to the change of the search range. When the search range becomes smaller and the dimidiate frequency is fixed, the search step should also decrease. Therefore, suitably chosen parameters yield good performance of HHT-AMD to decompose multicomponent micro-Doppler signals.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Trial** & **1** & **2** & **3** & **4** & **5** \\ \hline Search range & 5–50 & 10–40 & 15–30 & 17–28 & 19–26 \\ Dimidiate frequency & 25 & 25 & 24 & 23 & 22 \\ Search step & 5 & 4 & 3 & 2 & 1 \\ Decomposed components & 25 & 23 & 22, 26 & 21, 24 & 20, 25 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Influence of the parameters on the performance of HHT-AMD.  
Figure 9: The comparison of DSRs against SNR (signal-to-noise ratio) between HHT-AMD and HHT.
# The Design and Simulation of an Astronomical Clock
## 3 Features of the Modeled Astronomical Clock  
The astronomical clock whose design and motion study are presented in this paper will be capable of determining the mean positions of the Sun, the Moon, the lunar nodes and the zodiac circle as well as their motions during the year as seen from the Earth. This means that the locations and movements of the previously mentioned celestial objects are displayed on the astronomical clock face which represents the stereographic projection of the celestial sphere from the north celestial pole to the equator plane. In particular, the clock face indicates the celestial equator, meridian of a place, celestial tropics (Tropic of Cancer and Tropic of Capricorn), zodiac circle (ecliptic) and the horizon and set of almucantars above the horizon, as well as the almucantars of civil, nautical and astronomical twilights for the latitude of Belgrade. Moreover, the clock mechanism determines the phases of the Moon and displays them on an additional and separate screen.  
Since the modeled astronomical clock indicates simultaneously the mean positions of the Sun, the Moon and the zodiac circle during the year, the following data can be observed straightaway on its dial: local mean solar time, local mean sidereal time, the position of the Sun and the Moon on the ecliptic plane (in zodiac circle), the angular distance between the Moon and the Sun which determines the phase of the Moon, the altitude of the Sun and the local time of sunset, sunrise, dusk and dawn. The date of the winter and summer solstices, as well as the date of vernal and autumnal equinoxes, can also be detected and shown on the clock dial. Besides this, the date of lunar and solar eclipses can also be predicted and determined sufficiently accurately because the clock mechanism indicates the position of the lunar nodes.
## 3 Results and Discussion  
### Fresh Mortars Properties  
The water/binder (w/b) ratio used, and the obtained flow diameter and bulk density are presented in Table 3.  
According to the results in Table 3, the ideal water content for good workability was defined by ensuring that all lime-based mortars had a flow diameter of 150 \(\pm\) 5 mm. The exception were the mortars with the addition of nanosilica (A+NS) that were considered as presenting good workability despite having smaller flow diameters. In fact, the application trials showed an adequate workability of lime-nanosilica mortars with a slightly lower water ratio than A mortar, even if the flow diameter was reduced from 154 mm to 142-143 mm. This could be due to their greater specific surface area (SSA) allowed by the nanosilica, thus requiring a higher water amount to wet all the surfaces. At the same time, the very small NS particles covering the coarser aggregates' surfaces decrease the friction among particles, providing a lubricant effect that enhances the plasticity and workability, even with low w/b ratios [47; 48]. Thus, A+NS mortars did not evidence the need for a higher w/b ratio, despite their greater capacity to absorb water, resulting in their greater specific surface area (SSA).  
Moreover, within the nanosilica mortars, increasing the wt% of nanosilica from 3 to 5% decreases the w/b ratio while keeping a similar flow diameter (142-143). The increase in NS particles may have contributed to fill the voids among coarser particles, thus reducing the water needs, which apparently contradicts some research [21; 22].  
Finally, substituting part of the siliceous sand by limestone aggregate, in general, leads to a reduction in mixing water (wt %), namely in mortar with 30% of sand substitution (M\({}_{1}\)), without reducing the flow of the mortar. The reduction in the water content in air-time mortars with calcareous sand, notwithstanding their higher SSA and rate of water absorption, is ascribed to a physical effect, where the raise of the smaller diameter particles of the limestone sand allows to fill the voids among the coarser particles of the siliceous aggregates, increasing the density, but also facilitating the movement of the coarse particles, as reported in previous studies regarding the addition of limestone filler in mortars [48; 49]. In fact, very fine particles appear to have their own lubricating mechanism that requires less water than that needed by the larger particles to achieve similar flows [50].
### Motivation, Contributions, and Organization of the Survey
Since this survey is oriented towards wireless communication networks, we include a thorough discussion on how UAVs can help and what their primary use-cases are. Such discussion also reiterates the reasoning behind using UAVs in today's and future wireless communication networks and somehow uncovers the importance of the efforts trying to make the whole concept feasible;
* Section 5 presents different types of UAV deployments in order to explain the difference between standalone UAV deployments and UAV-assisted cellular networking because, according to this, the energy optimization model changes significantly;
* The energy optimization in UAV-assisted wireless networking is covered in Section 6, wherein the energy optimization is categorized according to the optimization objective (i.e., propulsion energy, communication energy, and joint optimization of propulsion and communication energies);
* For the sake of completeness of this survey paper, the overview of both conventional and ML algorithms employed in energy optimization of UAV-assisted wireless networks is given in Section 7;
* The energy optimization techniques, as the core part of this survey, are thoroughly discussed in Section 8. Various techniques are introduced by presenting the related literature, which is categorized in terms of the type of UAV deployment and optimization method employed (e.g., conventional and ML). With this section, the state-of-the-art is demonstrated, and a recently proliferating concept--called landing spot optimization--is also included to capture the energy optimization in UAV-assisted wireless networks holistically;
* To understand what and how other technologies can boost EE in UAV-assisted wireless networks, Section 9 mainly introduces the enabling technologies. In this section, a novel technology called RIS is included as one of the enablers, since RIS has recently gained a significant amount of interest in the research community;
* Section 10 identifies the primary challenges and possible future research directions in order to fill the gaps in the literature that would enable the overall UAV-assistedwireless communications concept to be more feasible. Lastly, Section 11 concludes the survey with final remarks. The summary of the paper's organization is illustrated in Figure 2.
## 3 Results and Discussion
### Modal Analysis  
Before carrying out the static analysis, it is necessary to check previously, by means of a modal analysis, whether the engine behaves like a rigid solid. If it had such behavior, the software would provide erroneous results.  
To do this, the model is subjected to a series of vibrations at different frequencies, which produces some deformations so that at high frequencies, elements appear that have a deformation greater than the reference deformation adopted by the software. Autodesk Inventor Professional provides the 8 lowest frequencies at which any part of the model is deformed, and if those frequencies are close to 0 Hz, it means that the element behaves like a rigid solid, and therefore, it would not make sense to perform a static analysis.  
For the blockage situation, the following frequencies were obtained: F1: 2.00 Hz, F2: 2.81 Hz, F3: 2.83 Hz, F4: 5.78 Hz, F5: 6.25 Hz, F6: 8.11 Hz, F7: 9.00 Hz and F8: 9.04 Hz. This means that, in this situation and as expected, the model behaves statically and, therefore, the study can proceed.  
For the emergency braking situation, the frequencies were different since some elements do not come into action. The results obtained were: F1: 3.39 Hz, F2: 4.25 Hz, F3: 6.37 Hz, F4: 6.42 Hz,  
Figure 16: Refinement of the mesh at the ends of the shafts in contact with the supports.  
F5: 6.71 Hz, F6: 9.08 Hz, F7: 9.26 Hz, F8: 9.46 Hz. Thus, the modal analyses of both situations were very similar without loads.  
On the other hand, as explained previously, the mesh size affects the exact places where stresses are concentrated, so the software allows the possibility of establishing a study on the convergence of the results by iterating the results in the regions that are considered more convenient. Therefore, for the static analysis a maximum of 10 cycles of iteration has been established, as long as the results vary more than 5% in each iteration. If the results in a region are less than that 5%, it stops iterating. In the same way, the greater the maximum number of iterations and the smaller the variation between results, evidently, the greater the computational requirements and the more prolonged the simulation time. In any case, this study is necessary in order to obtain a reliable result.  
The results of the convergence curves for the two situations studied are shown in Figure 17. In the blockage situation the convergence rate (0.035%) is reached at the fifth iteration (Figure 17a), and in the emergency braking situation, the convergence rate is lower (0.335%), reached at the third iteration (Figure 17b). Therefore, the evolution of both graphs allows us to determine that the results obtained is very reliable.
# A Review of Sharp-Switching Band-Modulation Devices
## 5 Alternative Applications of Sharp Switching
### Protection against Electrostatic Discharge  
Hazardous electrostatic discharge (ESD) on chip pads should be diverted by a protection device before they reach and damage the core circuitry (Figure 19a). An optimum protection is expected to respond quickly, by switching from a sleep mode (OFF) to a high current-drive I\({}_{\text{ON}}\) mode. Devices with an S-shaped current-voltage characteristic, operating in a certain voltage window, defined by the technology node and chip biasing, are of particular interest. This is exactly what band-modulation devices are able to do.  
A fundamental advantage is the tunability of the turn-on voltage via both the front-gate and back-gate voltages. The characteristics of the Z\({}^{2}\)-FET in Figure 5a,b are perfectly suited for ESD protection. Whatever maximum voltage V\({}_{\text{BD}}\) can be tolerated by the chip before breakdown and fatal damage, the trigger voltage can be adjusted to V\({}_{\text{ON}}\) = 0.9 V\({}_{\text{BD}}\).  
ESD tests are conducted with transmission line pulse (TLP) methodology, which records the voltage drop produced by a brief pulse of anode current. Reconstructed I\({}_{\text{A}}\)(V\({}_{\text{A}}\)) curves are shown in Figure 19b. A Z\({}^{2}\)-FET with a thicker body (12 nm) can handle a current of 8 mA/\(\upmu\)m [27]. Relatively long (100 ns) ESD discharges generate considerable self-heating in FD-SOI films, which lowers the maximum current. However, the advantage of ultrathin films over bulk silicon comes from a significantly faster response (120 ps) and a reduced overshoot voltage [53]. Figure 19c shows the waveform of the anode voltage just after an ESD event. The temporary voltage overshoot, where the device might be vulnerable, is minimized to 0.8 V.
## 3 Results and Discussion
### Verification of RCA and Formation of Hemin/G-Quadruplex  
The successful production of RCA and generation of hemin/G-quadruplex were verified by CV [34] and ECL. First, the stepwise fabrication of our proposed biosensor was characterized by CV, and the resulting cyclic voltammograms (CVs) are shown in Figure 3A. The redox couple of [Fe(CN)\({}_{6}\)]\({}^{3-4-}\), an indicator of surface chemistry, was used to record the electrochemical behavior of the sensor at different stages. A couple of [Fe(CN)\({}_{6}\)]\({}^{3-4-}\) redox peaks were observed with modified AuE, which was pretreated with SH-CP, HT, and TRA (curve a). After PP hybridizes with SH-CP, the current response (curve b) is smaller than that of curve a due to the increased negative charges on the DNA backbones. However, the current response decreased a great deal (curve c) after RCA, which was ascribed to the longer single strands on the electrode surface repelling the [Fe(CN)\({}_{6}\)]\({}^{3-4-}\) from the electrode.  
To confirm the formation of hemin/G-quadruplex on the electrodes, ECL of a different pretreated electrode surface in 10.0 mM phosphate buffer (pH 7.4) containing 50.0 mM K\({}_{2}\)S\({}_{2}\)Os was investigated. As observed with curve a in Figure 3B, the TRA-treated (incubation with 10.0 fM target DNA) HT/SH-CP/AuE generated a strong ECL signal. After RCA, the ECL intensity significantly decreased (curve c) due to the formation of hemin/G-quadruplex, which competitively consume dissolved oxygen  
Figure 3: Verification of RCA and formation of hemin/G-quadruplex. (**A**) CVs at the (a) TRA/HT/SH-CP/AuE; (b) PP/TRA/HT/SH-CP/AuE; (c) RCA/PP/TRA/HT/SH-CP/AuE in the presence of 10.0 fM target DNA, were detected in 0.1 M KCl containing 1.0 mM [Fe(CN)\({}_{6}\)]\({}^{3-4-}\) via scanning the potential from \(-\)0.2 to 0.6 V at a scan rate of 50 mV\(\cdot\)s\({}^{-1}\); (**B**) ECL responses of differently modified electrode: (a) PP/TRA/HT/SH-CP/AuE in the presence of 10.0 fM target DNA; (b) hemin/RCA/PP/TRA/HT/SH-CP/AuE in the absence of target DNA; (c) hemin/RCA/PP/TRA/HT/SH-CP/AuE in the presence of 10.0 fM target DNA. The ECL intensity of the modified electrode was recorded in 10.0 mM PBS containing 50.0 mM K\({}_{2}\)S\({}_{2}\)Os from 0 to \(-\)2 V (_vs._ Ag/AgCl) at a scan rate of 50 mV\(\cdot\)s\({}^{-1}\). The voltage of the photomultiplier tube (PMT) was set to 800 V during the process of detection.  
Figure 4B, the amplification duration varied from 30 to 180 min with an interval of 30 min. It was found that the ECL readout rapidly decreased with the RCA reaction time up to 120 min. However, the signal exhibited no further significant decrease when the reaction duration went beyond 120 min. This finding may be attributed to the fact that, when the reaction duration was increased beyond 120 min, the RCA products were entangled with each other, which could hinder extension of RCA product. Therefore, 120 min was selected as the optimum RCA time in subsequent experiments.
# Copenhagen Adduction Exercise to Increase Eccentric Strength: A Systematic Review and Meta-Analysis
###### Abstract  
_Background_: The purpose of this study was to systematically review the scientific literature about the benefits of using the Copenhagen Adductor (CA) exercise to improve eccentric hip abduction strength (EHAD), as well as to provide directions for training. _Methods_: A systematic search was conducted in three electronic databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The inclusion criteria were: (a) EHAD as outcome variable, with means and standard deviations before and after the intervention, (b) the study was a randomized controlled trial using the CA in the program intervention, (c) the article was written in English. The quality of evidence was evaluated according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) guidelines. A mini meta-analysis was performed to determine the overall effect. _Results_: Three studies were selected and included in this systematic review and mini meta-analysis. All articles reported significant enhancement in EHAD in football (soccer) players. The overall effect for the EHAD test was significant in favor to CA group (mean difference = 0.61; 95% CI from 0.20 to 1.01; \(p\) = 0.003) with large heterogeneity. _Conclusions_: CA exercise performed 2-3 times for 8 weeks is useful for improving EHAD in football players.  
**Keywords:** groin injuries; hip addiction strength; injury prevention; football; soccer
# Resource Management for Collaborative 5G-NR-V2X RSUs to Enhance V2I/N Link Reliability
## 3 System Model of Cellular V2X Network
### Antenna Model  
Antenna models are the most influential factors in performance evaluation, and the system model configures antenna models of BS-type RSUs and UE-type RSUs differently [15; 17]. In the case of an antenna of the BS-type RSU, it is a configuration of an antenna that satisfies three sectors in a hexagonal grid and has a height of 25 m. The number of antenna elements of all panels of the BS-type RSU antenna is up to 256 TX/RX antenna  
Figure 1: (**a**) Manhattan urban environment road and wrap –around model. (b) Network layout and vehicle distribution in a 5G\(-\)NR\(-\)V2X environment.  
elements. The array model is a uniform rectangular panel array represented by \(M\) (number of antenna elements in each row), \(N\) (number of antenna elements in each row), \(P\) (polarized type single-polarized or dual-parallelized), \(\mathrm{M_{g}}\) (number of antenna elements in each row), and \(N_{g}\) (number of antenna elements in each column). In 3 GPP, the configuration of the antenna array of the BS-type RSU is (\(M\), \(N\), \(P\), \(M_{g}\), \(N_{g}\)) = (8, 8, 2, 1, 1). The antenna panel configuration includes a uniform interval that satisfies (\(d_{H}\) (distance between horizontal arrays), \(d_{V}\) (distance between vertical arrays)) = (0.5, 0.8)\(\lambda\). In addition, the UE-type RSU has a different antenna configuration than the BS-type RSU. which height of the UE-type RSU is 5 m, and the number of antenna elements on all panels is up to 8 TX/RX antenna element which consists of (1, 2, 2, 1, 1). The interval between the antenna arrays has a uniform interval satisfying (\(d_{H}\), \(d_{V}\)) = (0.5, 0.8)\(\lambda\). In the antenna configuration, a larger number of antenna elements increase the power received from the VUE, enabling narrower beams and higher accuracy [22]. Section 5.3 considers 3D beamforming proposed by 3 GPP in BS-type RSUs, and identifies several limitations related to the range of adjustments caused by vertical cell geometry. It also introduces 3D beamforming, which combines the horizontal beam pattern adaptation and vertical antenna pattern adaptation with vertical pattern adaptation, maximizing the VUE throughput performance according to the increase in the receiving SINR of the vehicle terminal.
# A Parallel Two-Stage Iteration Method for Solving Continuous Sylvester Equations
## 1 Introduction
### Inner Iteration Scheme Based on the SYMMLQ Algorithm  
Equation (5) is changed into the following linear system by using the \(\overline{vec}\) operator  
\[Hx^{(k+1)}=\widetilde{f}^{(k)}, \tag{6}\]  
where \(H=A\otimes I+I\otimes B^{\text{T}}\), the vectors \(x^{(k+1)}\) and \(\widetilde{f}\) contain the concatenated columns of the matrices \(X^{(k+1)}\) and \(\widetilde{F}^{(k)}\), respectively, with \(\otimes\) being the Kronecker product symbol.  
Then, the SYMMLQ algorithm is proposed to solve the \(k\)th step iteration equation of the outer iteration scheme. For more details, we can refer to [8; 9]. The description of the corresponding SYMMLQ algorithm is given roughly in the following manner.  
Let \(\mathbf{y}=x^{(k+1)}\) and \(b=\widetilde{f}^{(k)}\). Then, Equation (6) can be written equivalently as  
\[Hy=b. \tag{7}\]  
Then, transform \(H\) into an \(i\times i\) symmetric tridiagonal matrix \(T_{i}\) by the Lanczos orthogonalization process. The coefficient matrix \(H\) is potentially unstable, and consequently \(T_{i}\) is not positive definite. So, the LQ decomposition ( Triangular Orthogonal decomposition, where \(L\) is a lower triangular matrix, \(Q\) is an orthogonal matrix ) is used to transform \(T_{i}\) into an \(i\times i\) lower triangular matrix \(L_{i}\), seen in the following flow chart: The SYMMLQ algorithm:  
\[H\xrightarrow[orthogonalization]{Lanczos}T_{i}\xrightarrow[ decomposition]{L_{i}P_{i}}. \tag{8}\]  
where \(T_{i}=L_{i}P_{i}\), and  
\[T_{i}=\begin{pmatrix}a_{1}&b_{1}&&&&\\ b_{1}&a_{2}&b_{2}&&\\ &b_{2}&a_{3}&\ddots&\\ &&\ddots&\ddots&b_{i-1}\\ &&&b_{i-1}&a_{i}\end{pmatrix},\ L_{i}=\begin{pmatrix}r_{1}&&&&\\ \delta_{2}&r_{2}&&\\ \epsilon_{3}&\delta_{3}&r_{3}&&\\ &\ddots&\ddots&\ddots&\\ &&\epsilon_{i}&\delta_{i}&r_{i}\end{pmatrix},\]\[P_{i}=P_{i-1}\begin{pmatrix}1&&&&\\ &1&&\\ &&\ddots&&\\ &&&c_{i-1}&s_{i-1}\\ &&&-s_{i-1}&c_{i-1}\end{pmatrix}.\]  
According to the above observation, we can establish the following stationary fixed-point iteration form for Equation (7):  
\[y^{(i+1)}=y^{(i)}+Q_{i}z_{i} \tag{9}\]  
where \(Q=(q_{1},q_{2},\cdots,q_{i})\) is an \(n\times i\) matrix and \(q_{1},q_{2},\ldots,q_{i}\) are orthonormal vectors which are computed by the Lanczos orthogonalization process. Here \(z_{i}\) satisfies the following equation:  
\[T_{i}z_{i}=\|r^{(0)}\|_{2}e_{1}, \tag{10}\]  
where \(r^{(0)}=b-Hy^{(0)},y^{(0)}\) is a given initial vector, and \(e_{1}=(1,0,\cdots,0)^{\mathrm{T}}\) is an \(i\)-dimensional unit vector. More details can be found in the literature [33].