esa-sceva/satcom-chunk-collection huggingface dataset:
## 5 Conclusions  
This paper revealed the possibility to achieve nonlinearity correlations between PAs operating in different saturation modes with different desired output power levels. Based on this finding, the main contribution, a cross-mode universal pre-distortion (CMUPD) technique is proposed for the linearization of PAs in low-sidelobe active antenna arrays. With the achieved nonlinearity correlation, a single pre-distortion feedback path is sufficient for linearizing the PAs in the whole antenna array using the proposed technique. Extensive simulation and experimental validations were conducted covering a broad range of operation specifications, including two PA classes (i.e., Class A and Class AB) and two signal bandwidths (i.e., 10 and 30 MHz). The validation results showed that the proposed technique can successfully achieve an averaged ACPR suppression of 13 dB for multiple GaN PAs operating with different output power levels desired in low-sidelobe arrays. Compared with other existing linearization techniques, the proposed CMUPD technology reduces the complexity of the system and the power consumption and hence shows the potential to be applied to satellite communication systems and 5G/6G networks, which exhibit stringent requirements on power efficiency and system linearity.  
Conceptualization, Y.L.; Data curation, Y.L.; Formal analysis, Y.L. and W.W.; Investigation, Y.L.; Methodology, Y.L.; Project administration, Y.H. and M.S.; Resources, Y.L.; Software, Y.L. and M.H.N.; Supervision, Y.H., M.S. and G.F.P.; Validation, Y.L.; Visualization, Y.L.; Writing--original draft, Y.L.; Writing--review and editing, Y.L., Y.H., M.H.N., F.J., W.W., J.R., Y.Y. and M.S. All authors have read and agreed to the published version of the manuscript.  
This research was funded by China Scholarship Council, grant number 202004910734.  
The authors declare no conflict of interest.
## 4 Experiments
### Camera Calibration  
To ensure high-precision measurements, this study conducts comprehensive intrinsic and extrinsic calibration of the RGB-D camera using a standard checkerboard pattern. Multiple images of the checkerboard with known dimensions are captured from various angles and positions within the camera's field of view to accurately determine the intrinsic parameters and distortion coefficients. Simultaneously, based on the spatial geometric relationships, the extrinsic transformation matrix from the camera coordinate system to the robotic arm's base coordinate system is computed. During the calibration, images are taken from different orientations and poses to enhance the robustness and accuracy of parameter estimation. Figure 12 shows examples of the checkerboard images acquired under various poses and viewpoints, which are used for corner point detection and intrinsic/extrinsic parameter computation.
# Heterodyne Angle Deviation Interferometry in Vibration and Bubble Measurements
## 3 Experimental Results
### Vibration Measurement
The transmitted light is the test beam. The test beam incident on a mirror (11) stuck on the test speaker (10) is reflected back to the original path and reflected by the beam splitter (9) again, and then incident into a face-to-face parallel mirror pair (13 and 14), which plays the role of an angular sensor. The rotation stage (15) is used to rotate the mirror pair to a suitable azimuth angle. After passing through another analyzer (17) and being detected by a photodetector (19), another interference signal is generated, and the phase shift between the s- and p-polarizations of the light due to the vibration is involved in its phase. The test signal \(I_{t}\) is also connected to the lock-in amplifier (22). Comparing these two signals, the phase difference caused by the vibration is obtained. From Figure 4a, the amplitude \(A\) of the vibration of the speaker caused by the driving signal from the function generation (21) is proportional to the deviation angle \(\theta\) of the reflection beam. In addition (from Figure 2) it is also proportional to the phase shift \(\phi\) of the mirror pair (13 and 14), i.e. \(\phi\left(t\right)\propto\theta\left(t\right)\propto A\left(t\right)\). Therefore, the output of the phase channel of the lock-in amplifier (22), the frequency and amplitude of the signal, are proportional to the frequency and amplitude of the vibration, respectively. The level (or amplitude) of vibration can be measured via the Fourier frequency transform in real time. We should use the spectrum function of an oscilloscope (Tektronix China Ltd, TDS 1012, Shanghai, China) to observe and record the spectrum of the phase signal \(\phi\left(t\right)\). For example, the spectrum of the signal from phase channel of SR830 for the speaker in the driving frequency of 100 Hz is shown in Figure 4b. This response frequency represents the vibration spectrum of the speaker. There are several harmonic frequencies in the spectrum of the speaker's response. It shows that some resonance of the speaker occurred. The resonance will enhance the vibration level. If the driving frequency is below 210 Hz, the harmonic frequency generation occurs obviously. If the driving frequency range is within 210-500 Hz, the spectrum shows that there is no other harmonic frequency generation and no resonance (see Figure 4c), so the error percentage in frequency is about 0.2
# Analysis of Lightweight Structure Mesh Topology of Geodesic Domes
## 4 Numerical Analysis Parameters
### Numerical Models  
Calculations and dimensions of the modeled two geodesic domes were performed in a numerical program considering the finite element method and using the currently applicable Eurocode 3 design standards for steel structures [52]. The geodesic domes were 49.97 m wide and 25.0 m high, but they had different mesh topologies depending on the method of dividing. In the numerical model, the maximal shape of finite elements did not exceed 0.5 m, as in the studies in [46; 47; 49].  
Using the first method of dividing the initial triangular face of a regular octahedron, a geodesic dome was obtained, the base of which was 4608-hedron, consisting of 3404 rods, 1200 nodes, and 2304 claddings. The second analyzed method allowed for shaping a dome with a 4704-hedron base, composed of 3500 bars, 1205 nodes, and 2352 claddings (Figure 1).  
The created structures were loaded with eight load cases, taking into account the self-weight of the dome (case 1) and the laminated tempered glass covering (case 2), evenly distributed snow (case 3) and unevenly distributed snow (case 4), as well as the effect of wind outside and inside the domes (cases 5-8). Based on Eurocode 1 [48], 16 load combinations were developed in the ultimate and serviceability limit states.
# On the Potential of the RST-FLARE Algorithm for Gas Flaring Characterization from Space
## 1 Introduction
Besides, owing to the availability of the long-term satellite data used, the RST-FLARE capability to reconstruct and monitor, in the spatiotemporal domain, the evolution of gas flaring activity in the investigated area, both in terms of areas affected by flaring sites and emitted volumes, will be assessed by considering independent sources of information. The paper is organized as follows. Section 2 describes both the satellite (Section 2.1) and ancillary (Section 2.2) datasets used in the analyses, and the developed methodology (Section 2.3). In Section 3 the results achieved applying RST-FLARE for flaring sites detection (Section 3.1), sources emissive power estimation (Section 3.2) and gas flared volumes computation (Section 3.3) are shown and discussed. In Section 4 a validation is carried out by comparing RST-FLARE outcomes to data provided by other sources to assess their accuracy. Finally, Sections 5 and 6 present discussion and conclusions, respectively.
###### Abstract  
Polyacrylamide (HPAM) and other traditional polymers have poor temperature resistance and salinity tolerance and do not meet the needs of high-temperature and high-salinity reservoirs. In this study, a new temperature-resistant and salinity-tolerant polymer QJ75-39 was synthesized using acrylamide (AM) as a hydrophilic monomer, 1-acrylamide-2-methylpropanesulfonic acid (AMPS) and N-vinylpyrrolidone (NVP) as functional monomers and DS-16 as a hydrophobic monomer. Through laboratory experiments, the properties (temperature resistance, salinity tolerance and aging stability), polymer injection and core displacement effect of the polymer were studied. The experimental results showed that the new polymer could meet the needs of polymer flooding technology in high-temperature and high-salinity reservoirs. Experiments showed that the polymer had a temperature resistance of 95 \({}^{\circ}\)C and a salinity tolerance of 1.66 \(\times\) 10\({}^{5}\) mg/L. When the temperature was 95 \({}^{\circ}\)C and the TDS was 55,376.8 mg/L, the viscosity of the polymer was 31.3 mPa s, and the viscosity remained above 30 mPa s after aging for 60 days. The polymer had good injectivity between 300 and 600 mD, and the injection pressure could reach equilibrium quickly. The oil recovery effectively increased with the growth in the amount of injected polymer. When the injection amount was 0.5 PV, the enhanced oil recovery was 20.65%. This study is of great significance for the application and popularization of polymer flooding technology in high-temperature and high-salinity reservoirs.  
high temperature and salinity; heavy oil; polymer flooding; enhanced oil recovery +
Footnote †: journal: Applied Sciences
# MERLIN: A French-German Space Lidar Mission Dedicated to Atmospheric Methane
## 3 Methodology
\(SSE\) is an ancillary data product that results from knowledge of the orbit height, instrument pointing, and measurement of the distance to the target (\(r_{T}\)) given by laser ranging methods. The geophysical auxiliary parameters (surface pressure, temperature profiles and water vapour profiles) are provided by (NWP) centres. Absorption cross sections of methane and other \"interfering gases\" for the desired temperature and pressure ranges are derived from line-by-line calculations using updated spectroscopic databases in combination with numerical models for the calculation of the integrated weighting function [26]. This method can also be applied to infer additional information on partial CH\({}_{4}\) columns above cloudy scenes by taking the signal reflected (scattered) by cloud particles at cloud tops [66]. In that case, \(p_{\mathrm{T}}\) will be the pressure at cloud top height and SSE corresponds to the height of the cloud top above \(Z_{NWP}\).
## 4 Proposed System Design Overview
### Optimised FTL-Assisted Edge IDS Learning
#### 4.3.2 Global Model Generation with Relational Knowledge Transfer
FL requires multiple iterations to generate a global model. Hence, the FT-CID model optimises the iterations with the help of attention-mechanism-based global model updating. \[\mathrm{h_{E}(i)=\frac{M\times w_{E}(i)}{\sum_{E=1}^{M}w_{E}(i)}} \tag{4}\]  
The FT-CID model minimises the communication rounds for convergence with the influence of the attention mechanism using Equation (4), where 'M' denotes the number of local models or network environments, and \(\mathrm{w_{E}(i)}\) refers to the weight of the local learning model parameters from the environment (E) for each ith iteration. In the FT-CID model, the gradient and dimensional difference-based attention mechanism limits the number of communication rounds and enhances the convergence speed without degrading the aggregation efficiency. The global shared model is generated with new logits and sent to each edge IDS to customise the local model. \[\mathrm{w_{E}(i)=f_{\mathrm{sigmoid}}\bigg{[}\frac{d(W_{\mathrm{GM}}(i),W_{ \mathrm{LM}}(i))}{\sigma_{E}(i)}\bigg{]}} \tag{5}\]  
The FT-CID model formulates Equation (5) to compute the gradient (\(\sigma_{E}(i)\)) and dimensional difference-based normalised result to update the attention weight of the learning model at each ith iteration. In Equation (5), the gradient refers to the results of the local learning model on the local datasets, which assist in aggregating the local model parameters within the optimal number of iterations until reaching the optimal convergence.
# A Performance Analysis of VANETs Propagation Models and Routing Protocols
## 4 Performance Metric and Simulation Setup
### Performance Evaluation Metrics
#### 4.1.5 MAC/PHY Overhead  
More packets can be sent and received with a more extensive network, causing overhead in packet routing. It is also termed as the saturation degree of a network. It measures the scalability of the network, i.e., if the overhead does not increase with the increase of vehicles number, then network performance is good. It depends on the total WAVE BSM sent. The bandwidth of the network is shared for routing as well as application packets. Less overhead infers better network performance.  
\[MAC-PHY_{oh}=totalPHY_{s}-totalAPP_{s}/(totalPHY_{d}). \tag{9}\]
# Detection for Frying Times of Various Edible Oils Based on Near-Infrared Spectroscopy
## 3 Results and Discussion
### Selection of Characteristic Wavelength  
In this study, the characteristic wavelengths of the spectra after 1D pre-processing were extracted by the correlation coefficient method. After 1D treatment, the five adjacent wavelengths were divided into one segment, and a total of 1045 segments were obtained, namely, 400 nm-408 nm, 402 nm-410 nm, 404 nm-412 nm,... 2490 nm-2498 nm. Number these wavebands by wavelength front to back,  
Figure 3: The frying times of peanut oil and rapeseed oil after multiplicative scatter correction (MSC) (**a**,**b**) and standard normal variant (SNV) (**c**,**d**) treatment.  
Figure 2: Spectrogram of soybean oil (**A**), peanut oil (**B**), rapeseed oil, (**C**) after first derivative (1D) treatment.  
in order of Seg1, Seg2, Seg3..., Seg1045. The correlation between each band and the frying sequence \(Y=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]\) was analyzed. Taking the data from the first round of frying experiments as an example, the correlation coefficient of each band is shown in Figure 4. Set the correlation coefficient threshold to ensure that the correlation coefficient of at least one band of each of the three oils is greater than the threshold. By comparison, the correlation coefficient thresholds of soybean oil, peanut oil, and rapeseed oil are determined to be 0.99, 0.96, and 0.99, respectively. At the same time, the correlation coefficient of the Seg384 band of all experiments is found to be greater than the threshold. The Seg384 band includes five wavelengths of 1166 nm, 1168 nm, 1170 nm, 1172 nm, and 1174 nm. Therefore, these wavelengths will be analyzed in-depth later.  
The average values of the data of the first eight rounds of three oils were taken to analyze the relationship between the absorbance of the corresponding wavelength of the Seg384 with frying times, as shown in Figure 5.  
Figure 4: Scatter plot of correlation coefficients for the first round of frying of three oils.  
By analyzing Figure 5, it is found that the wavelength at 1174 nm in soybean oil is decreasing, and the other wavelengths are with a growing trend. The wavelengths at 1168 nm and 1170 nm in the three kinds of oils increase monotonically with the increase of frying times. In the NIRS, an absorption peak at 1170 nm identifies the presence of an olefin functional C-H bond [25]. Besides, the diglyceride contained in the TPC undergoes a series of oxidation reactions during the frying process, and olefins are formed during the intermediate reaction [26]. Therefore, 1170 nm is closely related to the TPC content in frying oil. Moreover, the starch in the French fries has no effect on the absorbance at a wavelength of 1170 nm [25], which can eliminate the influence on the analysis caused by the continuous addition of French fries. In summary, 1170 nm can be used as the characteristic wavelength for predictive analysis of frying times.
## 4 Analysis of Results
### Analysis of Mediating Effect  
Mediating effects include direct effects, indirect effects and total effects. In this research, Sobel test was used to determine whether the intermediary effect of \"transaction security\" exists. Sobel test coefficients are as Table 11.  
In the case that \(\alpha\) equals 0.05, since the \(Z\) value of 6.56274 is much larger than the critical value of 1.96, there is a significant mediating variable \"transaction security\" between \"use attitude\" and \"behavioral intention.\" As there is also a significant relationship between \"attitude toward using\" and \"behavioral intention to use\" (\(t\)-value 17.112 ***), \"transaction security\" has a partially mediated effect.  
The converted data in this study are shown in Table 12. The direct effect of attitude is 0.732, and the total effect is 0.894. It is inferred that transaction security is the mediating effect. Therefore, the empirical data of the total effect and direct effect show that transaction security can be strengthened on consumer behavioral intent to use mobile payments.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Constructs**} & **Standardized** & **Unstandardized** & \multirow{2}{*}{**SE**} & \multirow{2}{*}{**CR**} & **Construct** \\  & **Factor Loading** & **Factor Loading** & & & \\ \hline ATT \(\rightarrow\) TS & 0.650 & 0.732 & 0.650 & 14.393 & *** \\ TS \(\rightarrow\) BI & 0.249 & 0.214 & & 7.304 &
## 2 Model Approach
### Analysis Method  
#### 2.4.1 Trend Analysis  
Trend analysis is a technique for analyzing patterns in timeseries statistically [25]. Theil-Sen median (SEN) was utilized in this study to further evaluate the trend in changing environmental variables in the studied area. Since the data need not follow a specific distribution and are resistant to errors, SEN trend analysis produces more accurate calculation  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Product Model** &
\begin{tabular}{c} **Surface** \\ **Parameters** \\ \end{tabular} & **Time Resolution** & **Spatial Resolution** \\ \hline PMLV2v0.1.7 & GPP & 8 d & 500 m \\ PMLV2v0.1.7 & ET & 8 d & 500 m \\ MOD13A2 & NDVI & 16 d & 500 m \\ SRTM V4.1 & DEM & - & 90 m \\ \hline \hline \end{tabular}
\end{table}
Table 1: Research data sources.  
results; it is now widely used in hydrology and climate timeseries research [26]. Its formula is as follows:  
\[\beta=Median\left(\frac{X_{j}-X_{i}}{j-i}\right)\ \forall\ j>i, \tag{2}\]  
where _Median (_)_ represents the median value, \(X_{j}\) and \(X_{i}\) are elements of the time series of the trend to be analyzed, in chronological order. If \(\beta\) is greater than zero, it represents an upward trend in the timeseries; otherwise, it represents a downward trend.
###### Abstract  
Global Positioning System (GPS) has been used in many aerial and terrestrial high precision positioning applications. Multipath affects positioning and navigation performance. This paper proposes a convolutional neural network based carrier-phase multipath detection method. The method is based on the fact that the features of multipath characteristics in multipath contaminated data can be learned and identified by a convolutional neural network. The proposed method is validated with simulated and real GPS data and compared with existing multipath mitigation methods in position domain. The results show the proposed method can detect about 80% multipath errors (i.e., recall) in both simulated and real data. The impact of the proposed method on positioning accuracy improvement is demonstrated with two datasets, 18-30% improvement is obtained by down-weighting the detected multipath measurements. The focus of this paper is on the development and test of the proposed convolutional neural network based multipath detection algorithm.  
Global Positioning System (GPS); Convolutional Neural Network (CNN); multipath detection; machine learning; high precision positioning +
Footnote †: journal: Computer Vision and Pattern Recognition  
1
# Exploring the Role of Emotions in Arabic Rumor Detection in Social Media
## 4 Research Methodology
### Dataset Collection  
There was no ready-made dataset in the Arabic language suitable for our experiments. While available datasets include real rumor incidents, they suffer from several limitations, such as the absence of reactions (i.e., replies) towards rumors. Additionally, these datasets contain duplicates and noise. To address these limitations, we created a new dataset following the methodology employed in the construction of the English rumor detection dataset [64]. Our dataset collection process spanned approximately two months and involved searching for rumors and non-rumors that occurred within the last ten years. We gathered false claims from Norumors ([[http://norumors.net/](http://norumors.net/)]([http://norumors.net/](http://norumors.net/)), accessed on 12 January 2023), a non-profit organization founded in 2012 to combat rumors manually in Saudi society, and true claims from news websites. The claims ranged from 2012 to 2022 and encompassed a broad array of topics, including politics, society, and health. To investigate the influence of crowd response, we collected related tweets that post claims on Twitter and then gathered the related responses posted for these claims using the Twitter API. After filtering and removing unrelated responses, such as advertisements or blank comments, we labeled false news as rumor and true news as non-rumor. The dataset we created consists of 403 events, including 202 false rumors and 201 true rumors. The total number of news posts and replies within these events, along with their veracity, are displayed in Table 2.
# Multi-User AF Relay Networks with Power Allocation and Transfer: A Joint Approach
## 1 Introduction
In this work, we consider a multi-user AF assisted network and focus on maximizing the sum rate of the designed framework by jointly optimizing optimal power allocation and transfer. We assume that each transmitter (sources/relay) has the capability of EH and that SWIPT takes place from the source nodes to the relay node only. In order to improve the reliability of the relay node, the source nodes use a dedicated energy control channel to transfer the harvested energy to the relay. Notice that the dedicated energy control channel is assumed to be orthogonal to the data transfer channel. Since the relay node operates in AF mode, the relay-assisted network suffers from a noise magnification problem. This presents an interesting question: how can we balance energy disbursement and energy transfer between EH nodes. In respect to this, we formulate an optimization problem for maximizing the sum rate by considering both energy and battery causality constraints. The formulated problem is non-convex and intractable in nature. In order to make the problem solvable, we utilize a successive convex approximation method. Furthermore, an iterative algorithm based on the dual decomposition technique is proposed to achieve the optimal strategy. The rest of this work is divided into the following sections. The system model, EH and WPT model, and the formulation of an optimization problem are described in Section 2. The proposed strategy is illustrated in Section 3. The numerical results are given in Section 4. We conclude the paper in Section 5.