esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 Materials and Methods
### Methods  
#### 2.3.1 Downscaled SIF  
(1) Dataset construction  
VIs and LAI have a strong correlation with SIF, and PAR plays a significant regulatory role in SIF. In this study, six VIs obtained from the Sentinel-2 satellite, along with LAI and PAR, were utilized as input parameters for the extreme gradient boosting (XGboost) model to downscale the TROPOSIF and eSIF data. Due to the low SIF values in the Saihanba area during the non-growing season, this study focused exclusively on data from the growing season (May-September). To match the resolution of the SIF data, the VIs for the 2020-2021 growing season were aggregated every 8 days to a resolution of 0.05\({}^{\circ}\). Given the relatively small area of the Saihanba Forest Farm, the study area was appropriately expanded beyond Saihanba to ensure an adequate sample size for modeling, as shown in Figure 1.  
(2) Downscaling method based on XGBoost  
The downscaling methods used by TROPOSIF and eSIF employ XGBoost. XGBoost is an advanced version of the gradient-boosted decision tree (GBDT) that constructs enhanced trees capable of handling complex nonlinear relationships [26; 45]. Owing to its remarkable speed, accuracy, and efficiency, XGBoost has become widely adopted in the remote sensing community as a preferred machine learning algorithm. It has been employed in various downscaling applications, including in studies on crop yield [46], groundwater [47], and surface soil moisture [48]. In this study, the XGBoost algorithm implemented in the Python library was utilized for the analysis. The VIs, PAR, and LAI data at a resolution of 0.05\({}^{\circ}\) were used as input variables to model SIF. To evaluate the performance of the model, the data were divided into an 80% training set and a 20% test set. Given the influence of various parameters on the XGBoost model's performance, the GridSearchCV method was adopted to optimize the parameters, with a specific emphasis on minimizing the root mean square error (RMSE). Through this process, the best-performing model was successfully identified and selected. The assumption was made that the modeling relationship between the 0.05\({}^{\circ}\) input variables and the SIF would not significantly differ at 0.0005\({}^{\circ}\). Bilinear interpolation was used to resample the LAI from 250 m to 0.005\({}^{\circ}\) and the PAR data from 0.05\({}^{\circ}\) to 0.0005\({}^{\circ}\). The final model incorporated VIs, PAR, and LAI data at a resolution of 0.0005\({}^{\circ}\) to downscale the SIF. Figure 2 illustrates the SIF downscaling process.
# Using Machine Learning to Predict Indoor Acoustic Indicators of Multi-Functional Activity Centers
## 4 Results and Discussions  
### Compatibility of the Field Measurement and Simulations  
The field measurement was carried out from 12 to 14 August 2020. By changing the ceiling materials of different areas and locations, a total of 15 different sets of field measurements were conducted. The 15 sets can be divided into the original situation of the space, the change of ceiling material by 1/3 area and 1/8 area. Under the same area, 7 different placement methods were measured (placed in the middle/placed forward and backward in the short direction/placed forward and backward in the long direction/striped arrangement in the short and long direction).  
Expanded metal mesh with a folding structure was used for the ceiling sound-absorbing material, and the unit size was 60 cm \(\times\) 60 cm \(\times\) 3 cm [35]. The sound absorption coefficient was tested in the reverberation room of the architecture acoustics laboratory at NCKU.  
The 3D model used in the simulation is shown in Figure 14. The calculation parameters were set pursuant to the calculation time and equipment. The impulse response length was 4000 ms, and the number of late rays was 16,000. The sound absorption coefficients and scattering coefficients of materials were set according to the literature values, and adjustments were made using the optimization tool. The material settings are shown in Table 7.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Material**} & \multicolumn{8}{c}{**Absorption Coefficient, Frequency Bands (Hz)**} \\ \cline{2-9}  & **63.5** & **125** & **250** & **500** & **1000** & **2000** & **4000** & **8000** \\ \hline Floor & 0.022 & 0.017 & 0.024 & 0.036 & 0.036 & 0.024 &  
The following describes the comparison results of actual field measurement and simulations (ODEON). The results of each receiver point (Figure 15) demonstrate that the acoustic indicators were affected by the distance between the source and the receiving point. C50 was underestimated at the three points closest to the sound source but overestimated at the last two points. C80 also had an almost similar tendency (except for point P5), while STI was generally overestimated but still showed differences between the front and back points.  
The _JND_ of the measured and simulated values of the overall data is shown in Figure 16, and the _RMSE_ is shown in Table 8. It exhibits good compatibility in reverberation time and clarity, while the performance of the _JND_ of STI is not very good (_JND_ > 2). Judging from the trend of measured and simulated values, almost all the data are overestimated and have a clear relationship. Therefore, we have speculated that the model settings still have some imperfections, such as ignoring curtains, ceiling fans, lamps, air outlets, etc. Nevertheless, the results of the two still have a certain compatibility.  
Figure 15: Boxplot of _absolute error_ by each receiver point. (**a**) RT at 500 Hz; (**b**) C50 at 500 Hz; (**c**) C80 at 1000 Hz; (**d**) STI.
## 6 Simulation Setup and Results
### Downlink Use Case  
For the downlink use case, we analyzed the impact of NGSO/GSO downlink transmission and terrestrial links on the GSO and NGSO ESIMs. We also analyzed whether FWA links need protection during downlink transmission. Further, we examined the ability of the proposed DSS techniques to provide interference protection to the satellite links and, if needed, to terrestrial links. In this simulation set, the available spectrum consists of three channels.
# Wideband-Narrowband Switchable Tapered Slot Antenna for Breast Cancer Diagnosis and Treatment
## 2 Design of the Proposed Frequency Switchable Tapered Slot Antenna
### Design of the Wideband Tapered Slot Antenna  
The conventional wideband TSA, which is suitable for a microwave imaging system, is shown in Figure 2. The conventional TSA was printed on an 0.8-mm-thick FR-4 substrate (\(\varepsilon_{r}\) = 4.3, tan \(\delta\) = 0.025) over an area of 80 mm \(\times\) 40 mm. In order to reduce the reflection of the electric field at the boundary between the proposed antenna and breast phantom, the FR-4 substrate was chosen because the dielectric constant of the substrate is similar to the dielectric constant of the breast phantom.  
The exponential slot is guided by the following equation;  
\[\mathrm{Y}=\mathrm{C}_{1}e^{Rx}+\mathrm{C}_{2},\;\mathrm{C}_{1}=\frac{y_{2}-y_{1} }{e^{Rx_{2}}-e^{Rx_{1}}},\;\mathrm{C}_{2}=\frac{e^{Rx_{2}}y_{1}-e^{Rx_{1}}y_{2} }{e^{Rx_{2}}-e^{Rx_{1}}} \tag{1}\]  
where \(R\) is the exponential rate and \(x_{1},\;x_{2},\;y_{1}\), and \(y_{2}\) indicate the start- and endpoints of the slotline [19]. A microstrip-to-slotline transition technique was applied to achieve stable wideband characteristics [20; 21]. To achieve a wideband transition, the microstrip-radial-open stub and slotline-round-short stub present virtual short and open circuits, respectively. The designed antenna interacted with the high dielectric human breast, so impedance characteristics had to be enhanced in order to maximize power transformation. Therefore, we designed flared slots to enhance the reflection coefficient in 3.5-5 GHz. The flared slots were designed near the input aperture of the tapered slot, where the current flow was strong, for effective input impedance control. The step impedance can be changed by controlling the exponential rate of the flared slots. After fine-tuning, the impedance matching characteristic was partially enhanced in the 3.5-5 GHz, as shown in Figure 3. A full-wave simulation was performed with Microwave Studio of Computer Simulation Technology (CST). As a result, the proposed TSA achieved optimal wideband operation in the 3.1-10 GHz.  
Figure 1: Configuration of the proposed system.  
Figure 2: Geometry of the fundamental tapered slot antenna (TSA): (**a**) front side, (**b**) back side.
# A Novel Strategy for VNF Placement in Edge Computing Environments
## 7 Experimental Results  
In this section, we cover the simulation environment and describe the performed experiments. Then, we analyze the obtained results, comparing our heuristic-based algorithm for VNF placement with three approaches, namely (i) the solution provided by the ILP solver; (ii) a greedy; and (iii) a random algorithm.  
The objective of the evaluation was to compare the performance of our heuristic-based algorithm against the other previously mentioned proposals concerning the results produced by each proposal in terms of the amount of energy and resources (CPU and memory) consumed by the execution of the generated placement plan. In addition, we executed a set of tests to verify the percentage of SFCs served by our smart VNF placement algorithm and the greedy and random algorithms.
###### Abstract  
This paper presents a methodology taking advantage of the GPOD-SBAS service to study the surface deformation information over high mountain regions. Indeed, the application of the advanced DInSAR over the arduous regions represents a demanding task. We implemented an iterative selection procedure of the most suitable SAR images, aimed to preserve the largest number of SAR scenes, and the fine-tuning of several advanced configuration parameters. This method is aimed at minimizing the temporal decorrelation effects, principally due to snow cover, and maximizing the number of coherent targets and their spatial distribution. The methodology is applied to the Valle d'Aosta (VDA) region, Northern Italy, an alpine area characterized by high altitudes, complex morphology, and susceptibility to different mass wasting phenomena. The approach using GPOD-SBAS allows for the obtainment of mean deformation velocity maps and displacement time series relative to the time period from 1992 to 2000, relative to ESR-1/2, and from 2002 to 2010 for ASAR-Envisat. Our results demonstrate how the DInSAR application can obtain reliable information of ground displacement over time in these regions, and may represent a suitable instrument for natural hazards assessment.  
high mountain regions; ground surface deformation; DInSAR; GPOD-SBAS +
Footnote †: journal: Remote Sensing, 8, 852
# Time-Sensitive Networking Mechanism Aided by Multilevel Cyclic Queues in LEO Satellite Networks
## 4 Time-Sensitive Networking Technique Aided by Multilevel Cyclic Queues  
In this section, we present a comprehensive analysis of the limitations of the current CQF technique. We then introduce a novel priority-based multilevel cyclic-queue mechanism aimed at delivering differentiated forwarding actions for a wide range of time-sensitive services. The proposed technique is centered on multiple queues that can cache TSFs with varying priorities, and a cycle priority mechanism that ensures all TSFs are forwarded within their respective deadlines.
## 3 Methodology
### Floquet Stability Analysis of VC Period-M Solution  
In the following section, the detailed process of stability analysis for VC period-\(M\) solution \(\mathbf{U}^{\prime}(\tau)\) obtained in Section 3.1 will be given by using Floquet stability theory [51].  
Introducing \(\mathbf{U}=\left[X,X^{\prime},Y,Y^{\prime}\right]^{\text{T}}=\left[X_{1},X_{2},X _{3},X_{4}\right]^{\text{T}}\), transform System (12) into:  
\[\mathbf{U}^{\prime}(\tau)=\mathbf{H}(\tau,\mathbf{U}(\tau))=\left[\begin{array}{l}X_{2} \\ \frac{1}{m}(\frac{W-F_{\tau}}{\delta_{0}\Omega_{M}^{2}}-\frac{cX_{2}}{D_{M}}) \\ X_{4}\\ -\frac{1}{m}(\frac{F_{y}}{\delta_{0}\Omega_{M}^{2}}+\frac{cX_{4}}{D_{M}}) \end{array}\right] \tag{20}\]  
where \(\Omega_{M}=N_{b}\cdot\Omega\ /M\).  
For Equation (20), superpose \(\Delta\mathbf{U}\) to perturb the VC period-\(M\) solution \(\mathbf{U}^{\prime}(\tau)\), i.e.,  
\[(\mathbf{U}^{\prime}(\tau)+\Delta\mathbf{U})^{\prime}=\mathbf{H}(\tau,\mathbf{U}^{\prime}( \tau)+\Delta\mathbf{U}) \tag{21}\]  
and retain only linear terms in the disturbance as:  
\[\Delta\mathbf{U}^{\prime}=\partial\mathbf{H}(\tau,\mathbf{U}^{\prime}(\tau))/\partial\mathbf{ U}^{\prime}(\tau)\cdot\Delta\mathbf{U} \tag{22}\]  
Then, the local linear stability of \(\mathbf{U}^{\prime}(\tau)\) can be provided by the stability information of Equation (22). As \(\mathbf{U}^{\prime}(\tau)\) is a period-\(M\) solution of the System (20), \(\partial\mathbf{H}(\tau,\mathbf{U}^{\prime}(\tau))/\partial\mathbf{U}^{\prime}(\tau)\)The Hsu method [22] is used to calculate the Floquet multiplier \(A_{m}\) and, according to the three means of \(A_{m}\) passing the unit circle of a complex plane, the period-\(M\) solution \(\mathbf{U}^{\prime}(\tau)\) can lose stability as follows [51]:  
* A transcritical, symmetry-breaking, or cyclic-fold bifurcation may originate when the leading multiplier crosses through the unit circle at +1. Herein, the cyclic-fold bifurcation emerges only at the turning point of a solution branch.
* A period-doubling bifurcation occurs when the leading multiplier crosses the unit circle at -1.
* A secondary Hopf bifurcation occurs when a complex pair of multipliers moves out of the unit circle.
# A Real-Time Data Delivery for Mobile Sinks Group on Mobile Cyber-Physical Systems
## 4 Conclusions  
Nowadays, Mobile Cyber-Physical Systems (MCPS) are widely exploited in various domains. In this environment, the Mobile Sink Groups (MSG) perform collaborative work with a common goal. Thus, data should be delivered to all mobile sinks in the group within a valid time. Traditionally, data delivery schemes for MSG have been proposed; however, as the existing flooding-based data delivery schemes have not been able to define end-to-end distance for each mobile sink, they struggle to satisfy the real-time requirement. To solve this problem, we proposed a scheme to model the MSG in a circular form, and to satisfy the real-time requirement for each member sink through data delivery using virtual grids. First, the proposed scheme models the MSG as one center point and radius, and defines the end-to-end distance based on the member sink furthest from the source node. Through this definition, the source node could could calculate the delivery speed which will be maintained during the data delivery. The data delivery process is largely divided into two phases: the main forwarding phase, which passing through the center of the mobile sinks from source node, and the branch forwarding phase at the branch point, which received the data through the main forwarding phase. In addition, even if some mobile sinks deviate from the initially calculated radius due to various environmental factors of MCPS, the connection of the sinks is ensured through the inner/outer agent concept. Through this process, the proposed scheme could deliver data to all member sinks in a timely manner. The performance evaluation results shows that the proposed scheme is superior to the existing schemes in terms of real-time communication for MSG.  
The proposed scheme could have achieved real-time data delivery for a single MSG; however, there could be more than two MSG, independent single mobile sinks, and static sinks in the actual MCPS environment depending on the application. Therefore, further studies on methods such as multicasting are required to deal with the numerous applications of MCPS environments.  
S.O., Y.C., S.K., C.K., K.J., and S.-H.K. contributed to protocol design and detailed algorithms. They also conducted the performance analyses. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the research grant of Pai Chai University in 2020.  
The authors declare no potential conflict of interests.
# A Network-Based Model for Optimization of Container Location Assignment at Inland Terminals
## 2 Literature Review
### Container Allocation at Seaports
A heuristic algorithm called \"neighbourhood\" was developed to model re-handling operations of containers. The discrete event simulation approach was used to mimic container arrival, storage, and retrieval. The model considered several factors, including the number of containers in each stack, the similarity between the containers in each stack (e.g., containers belonging to the same customer), and the residence time of the topmost container in each stack. The constraints considered in this system were weight (full and empty), size, and type. Based on these factors and constraints, stacks for container storage were allocated according to the hierarchy of constraints. Paper [48] studied the operational problem of sequencing container storage and retrieval requests for a single block of containers at a seaport, such that multiple locations were available for each storage container. The researchers proposed a method to store containers that would minimize the travel time of a single automated stacking crane. They adopted a three-phase solution method as well as a heuristic approach to solve the generalized asymmetric traveling salesman problem. The authors of [49] compared random and category stacking in simulations, which suggested that category stacking according to expected container departure time can reduce container relocations.
# New Optimal Design of Multimode Shunt-Damping Circuits for Enhanced Vibration Control
## 2 Methodology
### Design Optimization  
The major purpose of this work is to determine the optimal shunt circuit parameters for improving attenuation level for the damping multiple vibration modes of the composite piezoelectric system. To this end, a new design optimization approach is proposed that includes capacitances of current-flowing branches and shunt branch inductor values as new design variables in the optimization process. Next, the optimal design variables are determined by minimizing the \(H_{\infty}\) norm of the damped system using the particle swarm optimization (PSO) technique.
# Study on Magnetic Resonance Characteristics of Coal Sample under Progressive Loads
## 4 Testing Results and Analysis
### \(T_{2}\) Distribution Curve  
[PERSON] et al. [36] and [PERSON] et al. [40] discovered that there were two or three peaks in the typical \(T_{2}\) distribution curve. As can be obtained from Equation (1), the \(T_{2}\) distribution curve reveals the distribution characteristics of pore radius. The longer \(T_{2}\) is, the larger the pore radius is [41]. Figure 10 shows the \(T_{2}\) distribution curves of coal samples in Group C. As is shown, there are two peaks in most of the curves. According to the study [37], when there are two typical peaks in the \(T_{2}\) distribution curve, the left peak denotes AP while the right one stands for PP.  
Figure 10: \(T_{2}\) distribution curves of the coal samples in Group C: (**a**) Sample C-1, (**b**) Sample C-2, (**c**) Sample C-3.  
As can be known from Figure 10, the \(T_{2}\) distribution patterns of coal samples in Group C vary greatly from each other. The \(T_{2}\) peaks of AP and PP hold the overwhelming advantages, whereas that of CP is virtually non-existent in the curve. Figure 10a shows that compared with the case before loading, when the load reaches 3 MPa, the \(T_{2}\) peak value of AP witnesses a slight increase while that of PP declines remarkably. The \(T_{2}\) distribution curve moves to the larger value as a whole, which indicates that when the coal sample is in the elastic stage, AP tends to transform to PP. From Figure 10b,c similar conclusions can be drawn in the cases of C-2 and C-3. In the compaction stage, the \(T_{2}\) peak of AP displays an upward trend; on the contrary, that of PP tends to decline. Different from the case of progressive loading, when the load increases directly from 3 MPa to 7 MPa, the \(T_{2}\) distribution curve of C-2 does not change as drastically as C-1. This demonstrates that progressive loading can promote the evolution of pores and fissures in the coal sample significantly. As for coal sample C-3, when the load increases directly from 3 MPa to 11 MPa, AP transforms to PP rapidly. As the load increases gradually, the relaxation time becomes longer gradually as the \(T_{2}\) peak of AP begins to decrease, revealing that part of primary fissures close up when secondary fissures expand.
## 1 Introduction
The feasibility of the overall system dramatically relies on the incorporation of modules comprising microwave antennas, direct current (DC) booster, impedance matching network, power management techniques, and rectifying circuits. Therefore, the development of the RF-EH system is defined through critical trade-offs that researchers employ to achieve an optimal system in specific applications [16; 17]. Despite that, the available incident energy in RF-EH is the least among other alternative sources of energy, such as wind and solar energy. The RF-EH technology possesses many unique advantages. Most importantly, the method performs in any location with a strong radio frequency signal, including areas with no sunlight or indoor spaces with specialized transmitters. This review highlighted the RF-EH technology that converts the energy in RF signal incident at the antenna into usable DC power. Following a brief introduction, the following is how the review paper is organized: Section 2 describes the RF-EH system. The RF-EH approaches are discussed in Section 3. RF Concepts and Principles are provided in Section 4, while a review of the power-harvesting evaluation metrics is described in Section 5. Section 6 focuses on the brief details of the radio frequency environments. Section 7 is the explanation of the RF-EH circuit. Section 8 describes the comparison of the existing RF-EH applications. The review finally ends with a concise conclusion.
## 2 Background and Key Features
### UAV Communication  
The communication system of a UAV mainly consists of three parts: the ground control station, the UAV platform, and the communication link [30]. The ground control station is responsible for sending control commands to the UAV and receiving transmitted data. The UAV platform is equipped with various sensors, flight control systems, and communication devices, responsible for data collection, processing, and transmission. The communication link is used for information transfer between the ground station and the UAV. The stability, anti-interference, and transmission speed of the communication link have a direct impact on the success of UAV missions; hence, wireless communication technology plays a significant role in UAV systems.