esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Experimental Results and Analysis
### Complexity Analysis and Discussion
The inference time of the three equalizers measured in this study is as follows: Volterra = 0.844 s, traditional LSTM = 1.33 s, and two-stage equalization method = 2.37 s. Although the two-stage equalization method has a long inference time and currently has difficulty meeting the deployment requirements of real-time communication systems, since the method is not bound to the LSTM model, a shorter inference time can be achieved in the future by replacing the model and reducing the complexity of the algorithm. Next, we would like to elaborate on the potential future potential of our model and why we believe it can be practically deployed. We believe that, given the current early stage of THz communication development and its limited transmission range [33], there is not yet an urgent demand for highly optimized channel equalizers. However, as discussed in the Introduction section, THz communications are affected by numerous impairments--such as water vapor absorption, atmospheric molecular attenuation, and hardware-induced nonlinearity--that necessitate the use of more advanced equalization techniques. Our present work targets the equalization of nonlinear distortions introduced by THz channels. Experimental results indicate that, although our proposed method entails higher computational complexity, it consistently outperforms conventional nonlinear equalizers in both optimization accuracy and noise robustness. This validates the effectiveness of our two-stage approach in challenging channel environments. Looking ahead, we believe that practical deployment of the proposed equalizer is feasible through future model and hardware optimizations. Importantly, our method is not inherently bound to the LSTM architecture; the current design can be readily replaced with more efficient models. As [PERSON] et al. [43] have pointed out, by adopting lightweight alternatives and optimizing both the training and inference procedures, the path toward real-time implementation becomes realistic. This will be a key focus of our future work.
# Novel Designated Ownership Transfer with Grouping Proof
## 2 Proposed Protocol
### Integrity Verification Phase
When the verifier receives the final grouping proof \(P\) from the reader \(RID_{0}\), the verifier first computes the time difference between the current system time and the timestamp \(TS_{p}\) to check whether it was completed within the time threshold. Subsequently, the proof \(M_{p}^{q}\) is decrypted using the recipient's public key \(PK^{q}\) and a random number \(Np^{q}\) to obtain the signed proof \(M_{a}^{q}\), which is then decrypted using the transporter's public key and a random number \(Na\) to obtain the grouping proof \(M_{0}^{q}\). The verifier computes \(M_{0}^{q}\) to determine whether the received grouping proof \(M_{0}^{q}\) is identical, thus completing the grouping proof protocol.
# Evaluation of Radio Access Protocols for V2X in 6G Scenario-Based Models
## 3 Performance Metrics of V2X Technologies
### Code Rate  
The code rate (CR) is a measure of the efficiency of data transmission and is related to error correction. The code rate values for the 802.11p and 802.11 bd protocols are shown (see [31], Table 17-4). The code rate calculation for the LTE-V2X protocol \(CR^{LTE}\) is calculated by the following [22]:  
\[CR^{LTE}=\frac{n_{bits-RB}^{LTE}}{N_{RB}^{LTE}.\,n_{d_{syn}}n_{sc}.n_{bps}} \tag{1}\]  
where \(n_{bits-RB}^{LTE}\) is the total number of bits carried by resource blocks, \(N_{RB}^{LTE}\) is the number of resource blocks (see [32], Table 7.1.7.2.1-1), and \(n_{d\_{sym}}\) is the number of symbols in a sub-frame, which is equal to 14, although 9 symbols are used for the data [30]. \(n_{sc}\) is the number of subcarriers equal to 12 and \(n_{bps}\) the number of bits carried by the modulation scheme (see [32], Table 8.6.1-1).  
To calculate the code rate for the NR-V2X protocol, one should divide the target code rate value by 1024 (see [33], Table 6.1.4.1-1).
## 2 Inductive-Based Digital Isolation System  
The transceiver circuit of the implemented system utilizes the pulse polarity modulation scheme, which has the advantages of a compact circuit area, low power consumption, and high data rates. The presented scheme generates short pulses (in GHz sub-band) from the input digital signal for logic state transmission. The basic principle of GHz sub-band generation is demonstrated by the resulting CMOS inverter's harmonic overtones. When a sinusoidal input signal with a frequency of half the bandwidth of the CMOS process is applied under a VDD/2 bias condition, the output waveform is enhanced to a square shape  
Figure 1: Inductive-based digital isolation system for industrial sensor interfaces.  
with a fast slew rate. The Tx can then modulate these overtones and transmit them to the Rx using a small on-chip isolation transformer area.
## 4 Results and Discussions
### Characterization of Polypropolee Nanocomposite
#### 4.1.4 Thermogravimetric Analysis (TGA)  
TGA is a crucial technique for assessing the thermal stability and composition of polypropylene, graphene nanoplatelets, and their composites (refer to Supplementary Materials). The results show that PP typically undergoes a single-step thermal degradation process, with significant weight loss occurring around 350-450 \({}^{\circ}\)C. Pure PP generally leaves minimal residue after complete decomposition. In contrast, GNPs exhibit high thermal stability, undergoing substantial weight loss at temperatures above 600 \({}^{\circ}\)C, indicating excellent thermal resistance and leaving residual mass due to non-combustible components. The thermal stability of PP-GNP composites is influenced by the presence and distribution of GNPs within the PP matrix. Incorporating GNPs increases the composite's thermal stability, shifting the decomposition temperature to higher values. The residual mass after decomposition is higher for the composite than pure PP, attributed to the presence of thermally stable GNPs.  
Higher GNP content enhances thermal stability further, elevating decomposition temperatures. GNPs act as barriers, slowing the diffusion of volatile degradation products. Moreover, GNPs enhance the thermal conductivity of the composite, facilitating more efficient heat dissipation and delaying decomposition processes. In conclusion, TGA results underscore the beneficial effects of GNPs in improving the thermal stability and performance of PP-GNP composites through enhanced heat resistance and barrier properties.
# Burned Area Classification Based on Extreme Learning Machine and Sentinel-2 Images
## 4 Results and Discussion  
### Separability of Indices and Bands  
Figure 4 shows that the highest values for the SI index occur mainly for the DELTA dataset. This demonstrates the advantage of using a multitemporal strategy to improve discrimination of the categories that have suffered spectral changes due to wildfires [9; 55]. Furthermore, it is observed that for the DELTA dataset, the higher values are obtained by the spectral indices and not by individual bands. This shows the higher sensitivity of spectral indices that are designed to enhance the signal of burned areas [56]. As regards individual bands, those within the NIR zone (b6, b7 and b8A) show high separability values, which occur due to the great difference between the reflectance of vegetation affected or not  
Figure 3: Training and validation strategy.  
affected by fire [4, 57]. The NIR area is particularly sensitive to the internal cellular structure of leaves, and it reflects changes when an alteration takes place in this structure due to fire, senescence, a pathogen or deficiency of macronutrients [39]. On the contrary, bands of the visible zone (b2, b3, b4) show poor discrimination power, concurrent with what was obtained in [56]. Given the discrimination criteria considered, the features selected for training were the b6, b7 and b8A bands, and all of the spectral indices.
## 5 Overview of 5G-Enabling Technologies
### Integration of Non-Terrestrial Networks (NTNs) with 5G
#### 5.5.1 Overview of the NTN  
The non-terrestrial satellite network (NTSN) is a mega satellite constellation network that guarantees global network coverage with a high data rate, better security, and low latency communication, allowing it to provide more benefits over the terrestrial network. These capabilities can compensate for the drawbacks of conventional mobile communication [137; 138]. NTN operates through a spaceborne vehicle, such as the geostationary earth orbit (GEO), medium earth orbit (MEO), and low earth orbit (LEO) satellites. Unmanned aerial vehicles (UAVs) and high-altitude platforms (HAPs) may also be employed by NTN to provide coverage to areas where the conventional terrestrial network could not ordinarily reach [139]. The development of non-terrestrial networks, driven by low earth orbit (LEO) mega-constellations, has rapidly grown in recent years [140]. These networks can potentially revolutionize how we communicate, providing faster and more reliable connectivity to remote and underserved areas. The use of LEO mega-constellations in non-terrestrial networks is expected to increase in the coming years due to the advantages they offer in terms of low latency and high throughput and their ability to provide global coverage [141; 142; 143]. The use of advanced technologies, such as RIS and the integration of non-terrestrial networks with IoT, is key to the success of these networks and, when employed, will significantly improve the 5G signal quality and reduce the impact of atmospheric conditions on the transmission of data. Satellite communications have received much attention from researchers and industry due to the quick advancement of communication technologies. Particularly since the launch of numerous commercial satellite constellations, such as Starlink and OneWeb, various satellite technology-related concerns have taken center stage in 5G communications research [144].
# Experimental Study of the Performance of a Novel Vertical-Axis Wind Turbine
## 3 Experiment
### Experimental Procedures  
The IEC standard number IEC61400-12-1 requires that on-site measurements of electric power generated by wind turbines be made at various wind speeds. Based on the aforementioned requirement, the power generated by the AVAWT rotor is measured at various free-stream speeds. It is worth noting that the apparatus used in this experiment consists of a 55.88 cm \(\times\) 60.96 cm \(\times\) 182.88 cm custom-made plywood wind tunnel, a 17.78 cm-diameter \(\times\) 41.91 cm high AVAWT rotor, a Benetech hotwire anemometer (model: GM 8903 with a resolution of \(\pm\)0.1 m/s and a memory of 350 records), a Hylce MS 6252 digital anemometer with a resolution of \(\pm\)0.1 m/s, a Torquesense model RWT421-DD-KG torque transducer with a maximum torque range of 17.5 Nm, a steel ruler, a try-square, a Lenovo Ideapad P400 touch-screen laptop computer and a Canon PowerShot A570 IS digital camera. The torque transducer measures the torque, power output and rotational speed in RPM.  
Prior to carrying out the experiment, the setting of the fan used on the wind turbine was calibrated by measuring the speed of air (free-stream speed) at the center of the wind tunnel without the AVAWT rotor in place, using a hot wire anemometer, as shown in Figure 2. The free-stream speed was measured for each of the 12 settings on the fan motor's variable speed drive. All observations were recorded. Experiments were carried out after necessary safety precautions were followed. All view windows were firmly shut;  
leads from measuring instruments to the laptop were connected and the setup was put on by selecting the fan speed and turning on the fan motor. All readings were taken and tabulated.
# Experimental Study of Drag Torque between Wet Clutch Discs
###### Abstract
The test was conducted for three values of the gap: 0.3 mm, 0.5 mm and 1 mm. The results have shown that the clearance is a significant parameter with sensitivity on the drag torque higher than the oil flow or oil density. Clearance between the disks is also studied to understand their effect on the torque by [PERSON] et al. [14]. The authors took into consideration the distance of 0.1 mm and 0.2 mm. The result from the experiment shows that the drag torque is more than 50% lower for the wider gap. In the conclusion, the authors stated that clearance has the most significant effect on reducing drag torque. The aim of the research presented below is to recognize the influence of different factors on drag torque value between discs of wet clutch for rotational speed up to 7000 rpm. The investigated factors and investigation ranges were as follows:  
* the gap between clutch discs from 0.05 mm up to 0.5 mm
* based on the work of [PERSON] at al. [13] and [PERSON] et al. [14];
* the oil flow rate from 0 to 6 L/min and
* based on the work of [PERSON] et al. [11];
* the temperature of oil from 25 deg C to 80 deg C
* based on the theoretical analysis of [PERSON] et al. [12].
## 2 Related Work  
A large body of literary works have become available for routing in LEO satellite networks used for 5G/6G integration in recent years. In contrast, our work focuses on layer-agnostic routing in satellite networks used for space data delivery. We classified our related work into multi-layered satellite routing, LEO satellite routing, routing in Earth observation constellations, and multi-objective optimization routing in satellite networks.
# Experimental Study on Slender CFRP-Confined Circular RC Columns under Axial Compression
## 2 Experimental Program
### Material Properties  
The concrete used for casting columns was designed for a target compressive strength of 30 MPa and configured with Plain Portland cement. Medium sand was used as the fine aggregate, and pebble was used as the coarse aggregate. The diameter of coarse aggregate is 5-25 mm. The maximum aggregate size is 25 mm after screening. The mix ratio adopted was 1:0.43:1.25:2.91 (cement: water: fine aggregate: coarse aggregate). The cubic compressive strength (\(f_{\text{cu}}\)) measured value of the same batch concretes was 32 MPa at 28 days. The cylinder strength of unconfined concrete can be calculated by \(f_{co}=0.67f_{cu}=21.44\) MPa [4]. The minimum tensile strength of longitudinal steel bars was \(f_{y}=240\) MPa by testing in laboratory.  
The CFRP sheets were produced by TORAYCA in Japan. The measured mechanical properties of the CFRP are shown in Table 2. The CFRP was made of high strength unidirectional carbon fibers with 12,000 filaments per bundle and connected with polyamide. The epoxy adhesive was used to bond CFRP and concrete.
## 2 Related Work
On the other hand, few studies have considered the problem of interference avoidance for GEO systems. In fact, the frequency band allocated to the LEO beam determines the limit of its transmitting power. In view of the above problems, in the scenario of sharing spectrum with GEO, we model the problem of beam hopping resource allocation as a multi-objective optimization problem, and propose a mechanism to efficiently and flexibly allocate the time slot, power and bandwidth. The main contributions of this paper are as follows:  
1. In the multi-beam LEO satellite communication system, we model the joint allocation of communication time slot, frequency and power three-dimensional resources as a multi-objective optimization problem. While considering both the inter-beam CCI and interference avoidance to the GEO system, we achieve dynamic beam hopping according to different distribution of service request traffic in space and time. 2. We propose a flexible and efficient resource allocation mechanism in this paper. Firstly, we comprehensively measure the amount and urgency of traffic demand of all cells, and determine the illumination pattern through the weighted greedy strategy. Then, the interference clustering operation is performed based on the antenna model gain curve, and the lighting cells of the current time slot are clustered. Finally, the joint allocation of the bandwidth and power of the cells in each cluster is completed through the improved genetic algorithm or according to the constraint map. 3. In the scenario of even and uneven traffic distribution, a series of simulations are carried out under different traffic intensities to evaluate the performance of our proposed algorithm. Compared with random BH, polling BH and traditional genetic algorithm, the simulation results show that our proposed method can achieve higher throughput and access success rate, and reduce the average delay of all data packets while ensuring service fairness between cells. The remainder of this paper is organized as follows: Section 3 describes the system scenario and expounds the difficulty of solving the problem, and then the problem model and formulation are given. Section 4 elaborates the allocation mechanism and the specific implementation of our proposed algorithm. Section 5 shows some simulations and analysis to demonstrate the effectiveness of our proposed algorithm. Section 6 summarizes this article.
## 2 Materials and Methods
### Analytical Method  
Toluene Analysis Method: Toluene samples were analyzed using headspace-based gas chromatography (Nexis GC-2030, Shimadzu, Kyoto, Japan) with an automated headspace sampler (HS-10, Shimadzu, Kyoto, Japan). The headspace operating conditions were as follows: low shaking of the tested sample solution at 35 \({}^{\circ}\)C for 2 min, a GC cycle time of 25 min, and a vial pressurization time of 0.1 min. The gas chromatograph was equipped with a capillary column (HP-5, Shimadzu, Kyoto, Japan) and a flame ionization detector (FID). The injector, detector, and column temperatures were held at 150, 200, and 100 \({}^{\circ}\)C, respectively. Air and hydrogen served as fuel gases for the FID. Nitrogen served as a carrier gas, and the flow rate was 40.1 mL/min.  
Ferrous Iron Analysis Method: The ortho-phenanthroline colorimetric method is utilized [32]. Before conducting the ferrous iron test, a uniformly mixed culture suspension of 0.5 milliliters is injected into 4.3 milliliters of 0.5 mol/L hydrochloric acid and subjected to extraction at 30 \({}^{\circ}\)C for 24 h. Subsequently, 2.4 milliliters of the extraction solution are taken, and 0.32 milliliters of 6 mol/L hydrochloric acid, 0.32 milliliters of 2 mmol/L ammonium fluoride, 0.32 milliliters of 1% o-phenanthroline, 0.48 milliliters of ammonium acetate buffer, and 0.16 milliliters of distilled water are added. The absorbance of the solution is measured at 510 nm using a UV spectrophotometer (UV2550). Then, the total dissolved ferrous iron concentration is calculated according to the standard curve formula, \(c\left(Fe^{2+}\right)=c\times n\)  
Figure 1: Microbial experiment design.  
where \(c\) represents the ferrous iron concentration in the water sample as measured by the spectrophotometer in mg/L, and \(n\) is the dilution factor. As the dissolution of iron minerals gradually decreases during the reaction, the experiment employs the method of multiplying the proportion of dissolved ferrous iron values to total iron by the amount of total iron minerals added in order to determine the total ferrous iron generated during the reaction.
## 5 Conclusions and Future Work  
The primary results of this study and the hypothesis of EMG signal stationarity recorded from mGas muscle were accepted based on stationarity tests. It can be concluded that there existed a stationary segment in isotonic contractions for all window sizes. Based on the RA and MRA tests, EMG signals within the 100 ms, 500 ms, and 100 ms window sizes were outperformed by the 200 ms window size. As reported in [26], the EMG signal stationarity decreased as the length of window size increased for window sizes ranging between 125 and 1000 ms in isotonic contractions. In contrast to this study, EMG signal stationarity decreased as the length of window size increased only for window sizes greater than 200. The average percentage was slightly lower for window sizes less than 100 ms. The outcome affirmed that the analysis of EMG signals using TD features in 200 ms window size was reliable and applicable for isotonic contractions. Accordingly, EMG signal analysis for 200 ms and greater required careful interpretation due to non-stationarity, as observed in this study. To note, for prosthesis and orthotic applications, window sizes less than 300 ms are acceptable. Future studies should consider other window sizes such as 250 ms, as the performance of the MRA test had better results compared to RA tests for window sizes greater than and equal to 200. The discovery in this study contradicts the statement found in the literature [24] when analysing window sizes within the 100 ms range. To conclude, the stationarity of EMG signals was found acceptable for a 200 ms window size, and there were no differences in the average percentages of stationarity obtained from RA and MRA tests. Future works should compare the stationarity of EMG signals between 200 to 300 ms window size. Additionally, the effect of the type of windowing techniques has not been explored.  
**Acknowledgments:** The work presented in this study is funded by Ministry of Education Malaysia and Universiti Teknologi Malaysia under research university grant. VOTE NO: 15H81.  
**Author Contributions:** [PERSON], [PERSON] and [PERSON] conceived and designed the experiments; [PERSON] performed the experiments; [PERSON] and [PERSON]  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Author** & **Type of Contractions** & **Window Size (ms)** & **Stationarity Tests** \\ \hline
[25] & Isometric & 250 & Run, RA, and MRA \\
[26] & Isotonic & 125 & MRA \\
[26] & Isometric & 372 & MRA \\ This study & Isotonic & 200 & RA and MRA \\ \hline \hline \end{tabular}
\end{table}
Table 1: Comparison of suitable window size with different types of contractions. RA: reverse arrangement; MRA: modified reverse arrangement.  
analyzed the data; [PERSON], [PERSON], [PERSON] and [PERSON] contributed analysis tools; [PERSON] wrote the paper.  
The authors declare no conflict of interest.