esa-sceva/satcom-chunk-collection huggingface dataset:
# Near-Optimal Weather Routing by Using Improved A* Algorithm
## 3 Improved A* Algorithm
### Heuristic Function Using Haversine Method
#### 3.2.3. Cheap Heuristic  
In this study, the edge weight used for the A* algorithm was set to the ETA values calculated using machine-learning models, which are introduced in Section 4.1.3. The edge weight (actual cost, \(g\)) is the cost to move from one node to another node, and the edge costs between adjacent nodes were precalculated to improve the efficiency of the algorithm. However, the heuristic cost is the estimated path cost from the current node to the target node; thus, its value cannot be precalculated, unlike the actual cost. As a result, to estimate the path cost accurately, a large number of COG values should be precalculated; however, this is undesirable in terms of computational efficiency. Therefore, the heuristic cost must be calculated in a simple formula without using COG data.  
To preserve the admissibility of the A* algorithm, the heuristic cost should always remain lower than the actual cost. In this study, COG data contained in AIS data were used to calculate the heuristic cost (ETA) between arbitrary nodes and the target node. Because the ETA is distance/speed, theoretically using the maximum COG value of a ship recorded in the AIS always results in a smaller value than the actual value, thus satisfying the availability condition. However, as shown in Table 1 and Figure 5, the COG data distribution is sparse at high COG values, so using the maximum COG value results in more-conservative values than necessary. Therefore, as opposed to the perfect admissibility condition  
Figure 4: Calculation of COG.  
being met, the \(h\) cost was calculated using 99 percentile values for the SOG, as shown in Equation (7). Thus, the optimal ship route obtained using proposed A* algorithm can be considered near-optimal.  
The empirical maximum value of the SOG for the target vessel can be extracted from the AIS data, and Table 1 summarizes the statistical characteristics of the SOG data of an actual vessel for which the preprocessing has been completed. The methodology of data preprocessing is described in Section 4.1.3.  
\[h=\frac{dist(u)}{SOG_{99 th\ percentile}} \tag{7}\]  
where \(dist(u)\) means the distance between an arbitrary node \(u\) and the target node \(t\) and is calculated using the haversine method. This approach has the advantage of enabling the A* algorithm to converge efficiently to the solution; however, the optimality of the solution cannot be fully guaranteed because the admissibility of the heuristic has been violated.
## 4 Results and Discussion
### Slope Displacement Analysis
#### 4.2.1 Displacement Analysis
(3) Monitoring point M05 was located at ground level in the center of panel B. The horizontal movement in the strike direction of the working face initially increased and then decreased, while the horizontal movement in the dip direction of the working face increased continuously because it was near the downhill direction of the slope body. For the monitoring points that were less affected by the topography (e.g., M01-M04), as the working face advanced in the X direction, the monitoring points had a tendency to move toward the initial position. In the Y direction, the monitoring points always moved to the center of the working face. Figure 7: The relationship between the relative position of the slope body and the coal mining activity in both panels. (4) There was a non-uniform movement of monitoring points with the same horizontal movement trend, but different amounts and directions of movement. There was also non-uniform movement of monitoring points with different horizontal movement trends. These two important factors could cause damage to the mountainside, with the damage due to the surface deformation formed by the latter being greater than that due to the former. Surface points were affected by coal mining in a complex temporal and spatial process, according to the X-Z section of the monitoring point moving trajectory, as shown in Figure 9.  
(1) The ground movements at M02, M03, M04, and M06 in the Z direction were large and were affected by the mining activity in panel A. Monitoring point M01 experienced less subsidence because of the relatively short monitoring time. Larger surface subsidence values were recorded closer to the center of the panel. Monitoring point M05 was mainly affected by the coal mining in panel B. Because the mining thickness in panel B was small, there was less subsidence at this monitoring point than at other locations. Figure 8: The track of the horizontal movement of the monitoring points. Figure 9: The X–Z profile movement trajectory at the monitoring points. (2) The horizontal movements in the X direction at M02, M03, and M04 were larger than those at other monitoring points, and were mainly affected by the downhill direction of the slope body. When the working face passed over these points it was affected by the topography, with little backward movement in the X direction (i.e., moving to the initial position). The backward movement in the X direction was largest at M05, with M06 also showing a trend of backward movement. (3) The backward movement of the monitoring points in the X direction is a phenomenon of surface movement caused by the influence of movement ahead and behind a surface point during the passage of the working face. This was clearly observed at M05 and M06, but was limited to varying degrees by the topography at the other monitoring points.
# Cascaded Frequency Selective Surfaces with Matryoshka Geometry for Ultra-Wideband Bandwidth
## 4 Results Analysis  
The simulated results were obtained with the commercial software Ansys Designer(tm) for a FR-4 substrate with dielectric constant \(\varepsilon_{r}=4.4\) and thickness \(h=1.6\) mm, using the High-Frequency Simulation Software (HFSS) mode [43].  
A plane wave source was considered with post-processing settings of 1 V for both horizontal and vertical polarizations and the infinite array setup with boundaries in the dimensions of the unit cell, \(W_{x}\) and \(W_{y}\), shown in Table 3. These settings were made to infinitely repeat the simulation of the geometry traced on those boundaries.  
The frequency sweep had a linear step distribution from 0 GHz to 10 GHz with a step size of 0.05 GHz. Then, this was adjusted for a 0.01 GHz step size ranging from 1 GHz to 5 GHz.  
Figure 10: Cascaded FSS with different gaps. (**a**) The FSSs with a spacing of one acrylic support, 2 mm wide. (**b**) Spacing of 8 mm using two supports of 3 mm and one of 2 mm. (**c**) Spacing of 20 mm using 6 acrylic supports: two of 5 mm, two of 3 mm, and two of 2 mm.
## 2 Background and Pseudo-Doppler Principles
### Implications in an OAM Radio Link
Therefore for OAM mode \(k=1\), the radius of the transmitting array is determined as  
\[\frac{2\pi r_{1}\sin\phi}{\lambda}=2\Rightarrow r_{1}=\frac{2\times 0.05\text{m} }{2\pi\times(20\text{m}/1000\text{m})}=0.80\text{ m}\]  
and for \(k=4\), the radius of the TX circular arrays is  
\[\frac{2\pi r_{4}\sin\phi}{\lambda}=5\Rightarrow r_{4}=\frac{5\times 0.05\text{ m}}{2\pi\times(20\text{m}/1000\text{m})}=2.0\text{ m}\]  
Such size of antenna is not excessive for a sub-6 GHz base station. If the element spacing is to be half of the RF wavelength as indicated in Figure 7, then the outer array for OAM mode \(k=4\) would require 500 elements and the inner one for \(k=1\) would require 200 elements. Note that because  
Figure 7: Example of an OAM radio link using pseudo-Doppler modulator in the off-axis receiver. negative OAM orders are equally handled by the same system (resulting in negative pseudo-Doppler shifts at the RX), a total of 9 OAM modes could be transmitted on this link.
# A Reflection-Type Dual-Band Phase Shifter with an Independently Tunable Phase
## 3 Simulation and Measurement Results
### Simultaneous Dual-Band Operating Results  
Figure 11 shows the simulated and measured results of the dual-band PS in the circumstance where the bias voltages of the \(f_{\rm{L}}\) and \(f_{\rm{H}}\) bands were simultaneously shifted. As seen in Figure 11a, the PSRs of the \(f_{\rm{L}}\) and \(f_{\rm{H}}\) bands were \(114.134^{\circ}\pm 8.43^{\circ}\) and \(114.017^{\circ}\pm 5.409^{\circ}\) within the bandwidth, a result achieved by varying the bias voltage from 0 V to 16 V. The ILs were smaller than 1.867 dB and 1.897 dB, and the input/output RLs were higher than 19.695 dB and 16.833 dB within bandwidth of the \(f_{\rm{L}}\) and \(f_{\rm{H}}\) bands.  
A comparison of the performance of the proposed dual-band PS against previously reported PSs is provided in Table 6. Although the previous PSs perform very well, in as much as they achieve a wide PSR and low in-band PD, these designs are single-band operation only. The proposed design, in contrast, is of a dual-band PS with independently controllable phase shifts in each band. In addition, unlike previously published papers, using a transmission line with an electrical length of \(\lambda/4\) without a band-pass filter or a band-stop filter has the advantage of being able to fabricate more easily without using a compound process and can operate independently without affecting the co-operating frequency. This proposed design had a higher RLs, lower in-band PDs, and used fewer varactor diodes than previous PSs.  
Figure 10: Simulated and measured results of a dual-band PS achieved by varying the bias voltage of the high\(-\)band while fixing the bias voltage of the low-band at 0 V: (**a**) PSRs; (**b**) ILs and input/output RLs.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Bias Voltage [V]** & **Phase [\({}^{\circ}\)]** & **PSR [\({}^{\circ}\)]** & **PD [\({}^{\circ}\)]** & **Max. II [dB]** & **Min. RL [dB]** \\ (\(f_{\rm{L}}\)/\(f_{\rm{H}}\)) & **@\(f_{\rm{L}}\)** & **@\(f_{\rm{H}}\)** & **(\(f_{\rm{L}}\)/\(f_{\rm{H}}\))** & **(\(f_{\rm{L}}\)/\(f_{\rm{H}}\))** & **(\(f_{\rm{L}}\)/\(f_{\rm{H}}\))** \\ \hline
2/0 to 16 & 60 & 113.947 & \(\pm 1.035/\pm 5.555\) & 1.485/1.851 & 20.670/16.710 \\
16/0 to 16 & 114 & 114.242 & \(\pm 0.168/\pm 5.897\) & 1.514/1.735 & 19.662/16.724 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Measured results of the dual-band PS achieved by varying the bias voltage of the high-band while fixing the bias voltage of the low-band.
###### Abstract  
Exposure to fine particulate matter (PM\({}_{2.5}\)) impairs the respiratory system and increases the morbidity and mortality of respiratory diseases. Even though aerobic exercise is known to improve pulmonary function in diverse populations, it can lead to an increase in the inhalation of PM\({}_{2.5}\) in polluted environments. We aimed to investigate the effects of aerobic exercise under high PM\({}_{2.5}\) conditions on the pulmonary function in young adults. Nine healthy young men performed indoor treadmill running in both high and low PM\({}_{2.5}\) conditions (59.0 \(\pm\) 2.1 vs. 7.8 \(\pm\) 1.0 \(\mu\)g/m\({}^{3}\)) by a crossover study design. Pulmonary function was assessed by spirometry and diffusing capacity for carbon monoxide (DLCO) at pre- and 1-h post-exercise. There was no difference in the response of pulmonary function and lung diffusion capacity to the acute aerobic exercise in high and low PM\({}_{2.5}\) conditions (\(p\geq 0.09\)). These findings indicate that aerobic exercise in high PM\({}_{2.5}\) conditions may not adversely affect pulmonary function in healthy young adults.  
engenders morphological changes in nasal airways and increases the risk of respiratory diseases [10].  
Aerobic exercise is known to improve pulmonary function in asthmatic patients [11]. Even in healthy individuals, pulmonary function was enhanced after participating in regular aerobic exercise [12; 13; 14]. However, performing aerobic exercise under high PM\({}_{2.5}\) conditions might annul the positive effect of the exercise and impair the respiratory system. Substantially increased minute ventilation during aerobic exercise is likely to increase the number of inhaled particles into the lungs [15; 16]. In addition, increased velocity of airflow during exercise can cause particles to reach a deeper region of the respiratory system [15]. Previous findings on the effect of aerobic exercise on pulmonary function in high PM\({}_{2.5}\) conditions are limited, and their results are still controversial [17; 18; 19; 20; 21]. Hence, this study aimed to demonstrate the effect of acute moderate-intensity aerobic exercise on pulmonary function under high PM\({}_{2.5}\) conditions compared with low PM\({}_{2.5}\) conditions. We hypothesized that exposure to high PM\({}_{2.5}\) conditions during aerobic exercise would negatively affect pulmonary function due to the elevated PM\({}_{2.5}\) inhalation caused by the increased minute ventilation during exercise. Moreover, our study controlled indoor PM\({}_{2.5}\) conditions with penetrated particles from the outdoor environment to emphasize that the influx of outside ambient air has a negative effect on indoor air quality.
## 3 Guide-Vane Layout  
To counteract the undesired reservoir sedimentation, necessary measures are required. River training approaches are commonly used, which include construction of spur dikes [28; 29; 30], rock vanes, and bendway weirs [31; 32], various types of revetments [33], and dredging [34]. Each approach has its advantages and limitations. The choice is also dictated by the local conditions. For example, the presence of riparian structures precludes the use of spur dikes. All these approaches are discussed in the course of the pre-study. However, limited by the practical situation, they are excluded for use at the site.  
Guide vanes are instead chosen as the alternative. The layout of guide vanes refers to their positions and configuration (form, length, width, and height) and is usually associated with a number of factors, including reservoir bathymetry, its shape in planform, and riparian structures. Field investigations show that the main current downstream of the river bend runs obliquely towards the right bank and generates, depending on flow discharge, flow circulations of significant size. The guide vanes are oriented in such a manner that the main reservoir current is effectively deflected to follow the direction towards the gates. In addition, the vane configuration should be as simple as possible.  
Figure 6 shows the sketch of the layout. Based on field investigations, an array of parallel vanes is suggested, running along a cross-section downstream of the bend. The vanes are vertically placed and straight in planform, with equal distance between and both ends slightly rounded. A (\(X\), \(Y\)) coordinate system is set up, with \(X\) running along the central sluice pier's centerline (positive upstream) and \(Y\) along the cross-channel axis  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Case** & \(Q\) **(m\({}^{3}\)/s)** & \(S\) **(kg/m\({}^{3}\))** & \(Z_{\text{u}}\) **(m)** & \(Z_{\text{d}}\) **(m)** & \(e\) **(m)**  
of the bulkhead gates (positive towards right bank). Let \(a\), \(b\), \(h\), \(c\) and \(\alpha\) denote vane length, thickness, height, distance between two neighboring vanes and angle (positive anticlockwise) that the vanes form with \(X\). The exact positioning of the vanes in the reservoir and the geometric parameters are finalized in the physical model tests.  
It should be pointed out that, from the hydraulic point of view, the proposed position of the guide vanes may not be the most favorable. However, the practical conditions here limit the possibility to place them further upstream or somewhere else. A curved vane shape or a varying vane width is not examined in the study.
# Recent Development of Morphology Controlled Conducting Polymer Nanomaterial-Based Biosensor
## 3 Polyaniline-Based Electrodes
### 2D Nanostructures  
Various methods were used to make PANI nanofilm-based biosensor electrodes with a large surface area. [PERSON] et al. utilized the inkjet printing technique to create ammonium persulfate initiator solutions that were used to produce patterned PANI nanofilms via vapor deposition polymerization of aniline (Figure 6a) [105]. Inkjet printing is an efficient alternative to conventional photolithographic methods for the production of versatile CP-based micro- or nanoelectronics because of its cost-effectiveness, high-speed patterning capabilities, flexibility, morphological adjustability, and widespread applicability. The patterned PANI layer was applied for dopamine detection by monitoring the observed changes in the flowing current. [PERSON] et al. synthesized PANI nanosheet-based thin-films using the screen printing method to generate glucose electrochemical sensors [106]. Additionally, they synthesized  
Figure 5: (**a**) Au nanoparticles incorporated into PANI nanowire-based glucose electrochemimuminescent biosensors [100]. Copyright 2017, Elsevier. (**b**) The electrochemical biosensors generated from PEGlated PANI nanofiber-based breast cancer susceptibility gene (BRCA1) [101]. Copyright 2017, American Chemical Society. (**c**) The synthesis of PANI nanofibers via electrospinning; these nanofibers were subsequently employed to manufacture cyclooxygenase-2 (COX-2) sensor transducers [102]. Copyright 2019, Springer.  
NiO-coated PANI nanosheets using in situ polymerization processes to facilitate glucose detection (Figure 6b) [107]. Conversely, [PERSON] et al. attached 2D PANI layers directly onto silicon substrates using dilute oxidative polymerization reactions to fabricate B-type natriuretic peptide (BNP) biomarker FET sensors [108]. Note also that electrochemical deposition was effective for manufacturing polyaniline nanofilms. [PERSON] et al. generated electrodeposited 2D PANI layers on a gold electrode pattern for use as FET BNP antibody FET sensors (Figure 6c) [109].
## 6 Simulations and Experiments  
The method was implemented in the Altera Cyclone IV FPGA with the parameters given in Table 2. Figure 14 shows a photograph of the prototype. It consists of a FPGA (EP4 CE22E22C7N, Altera Corporation, San Jose, CA, USA) control board, a switching power supply, a MOSFET driver, and a power circuit. The method is verified in the simulation using Saber.  
Figure 13: Bode plot of the single loop and double loop.  
Figures 15 and 16 show the simulation and experimental transitional waveforms of the main switches, respectively. During the turn-on commutation, the drain currents \(i_{d3}\) and \(i_{d4}\) begin increasing after the drain-source voltage \(v_{ds3}\) and \(v_{ds4}\) drop to zero. ZVS of S\({}_{4}\) is achieved with the operation of S\({}_{\rm r1}\), whereas the auxiliary switches are not turned on to achieve ZVS of S\({}_{3}\). Regarding the turn-off commutation, the drain current overlaps the drain-source voltage slightly because the resonant capacitance is not large enough. Due to the parasitic components, ringing occurs during the commutation in the experiment.  
Figure 14: Photograph of the prototype.  
Figure 15: Simulation results of the current and voltage of the main switches when \(i_{o}\) = 8 A. (**a**) S\({}_{3}\); (**b**) S\({}_{4}\).  
Figures 17 and 18 show the simulation and experimental waveforms of the auxiliary current with an 8 A, 100 Hz sinusoidal output current. The peak auxiliary switch current follows the load current with clear load adaptability. It can be seen that the lower the load current, the lower the auxiliary current.  
Figure 16: Experimental results of the current and voltage of the main switches when \(i_{o}=8\) A. (a) S\({}_{3}\); (b) S\({}_{4}\).  
Figure 17: Simulation waveforms of the auxiliary current with an 8 A, 100 Hz sinusoidal output current.  
Figure 18: Experimental waveforms of the auxiliary current with an 8 A, 100 Hz sinusoidal output current.  
Figures 19 and 20 show the simulation and experimental results of the output current with and without active damping method, respectively. Figure 19 demonstrates that strong resonance occurs in the output current without the active damping method, because closed-loop poles are outside the unit circle shown in Figure 11. After utilizing the capacitor current feedback, the poles can be moved into the unit circle. Therefore, the system can be stable both at the DC or sinusoidal output current conditions. Figure 20 also demonstrates that active damping is necessary to maintain stability and current quality.  
Figures 21 and 22 show the simulation and experimental results of the load dynamic response, respectively. The results demonstrate that the output current tracks the reference current quickly. However, a bit of overshot exists in the transient response.  
Figure 19: Simulation results of the output current with and without active damping method: (**a**) DC output current; (**b**) sinusoidal output current.  
Figure 20: Experimental results of the output current (**a**) without and (**b**) with active damping method.
# Federated Learning for Maritime Environments: Use Cases, Experimental Results, and Open Issues
## 5 Open Issues
### Non-Identical Training Data from Diverse Sources  
Non-identical data manipulation is a crucial step towards data integration from diverse sources. In this case, there might be incompatibilities in the received data, especially in highly correlated environments. Recent solutions have proposed batch federated aggregation, succeeding in suppressing oscillations due to non-i.i.d. data during FL training [18].
# COSMIC-2 Mission Summary at Three Years in Orbit
###### Abstract  
We summarize the status of the FORMOSAT-7/COSMIC-2 (COSMIC-2) mission which has completed its first three years in orbit. COSMIC-2 is a joint U.S./ Taiwan program consisting of six satellites in low-inclination orbits with the following payloads: Global Navigation Satellite System radio occultation, in-situ ion velocity meter, and tri-band radio frequency beacon. The constellation is in its final orbit configuration and reached mission full operating capability in September 2021. An extensive calibration/validation campaign has to date enabled the release of all baseline neutral atmosphere products and nearly all baseline ionosphere products. The mission is providing usually more than 5000 neutral atmosphere RO profiles per day with a precision better than 2 urad from 30-60 km altitude. Each day, nearly 12,000 combined total electron content occultations and arcs are generated with absolute accuracy of better than 3 TECU. IVM density precision is at or below the 1% requirement. Neutral atmosphere and ionosphere latency, measured from time of observation to product creation time, is below 30 min median. Data products are delivered in near real-time to operational weather and space weather centers and made available openly to the research community. New ionosphere products specifying the presence and absence of scintillation are under development and planned for future release.  
Keywords:FORMOSAT-7; COSMIC-2; satellite mission; radio occultation; neutral atmosphere; ionosphere +
Footnote †: journal: _Atmosphere_