esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 GPR Image Characteristics Analysis
### Characteristics of Cavity Defect  
In the instantaneous amplitude image (see Figure 9a), when the travel time of the electromagnetic wave was 12 ns, an anomalous reflection wave was produced by the cavity defect between the 70 th and 130 th traces, appearing as a \"hyperbolic shape\". The second hyperbolic-shaped anomalous reflection wave corresponded to the lower boundary of the cavity defect. Given that the propagation speed of the electromagnetic wave in the air was 0.3 m/ns, the two-way travel time of the upper and lower boundaries was calculated to be 4 ns, resulting in 0.6 m between the upper and lower vertices of the cavity defect, which aligned with the model design. The single-trace waves at around 6 ns and 6.6 ns exhibited two closely spaced, continuous peaks. For subgrade void defects, the upper and lower interfaces of the defect and the subgrade's structural layers can be deduced based on the instantaneous amplitude and the normalized amplitude of the single-trace wave in the GPR image. In the instantaneous phase image, when the travel time of the electromagnetic wave was approximately 2 to 8 ns, the characteristic of the reflection wave's instantaneous phase image was manifested as continuous in-phase axes, indicating uniform and well-compacted structural layers.  
In the instantaneous phase image (see Figure 10a), when the travel time of the electromagnetic wave was approximately 2 to 8 ns, the characteristic of the reflection wave's instantaneous phase image was manifested as continuous in-phase axes, indicating uniform and well-compacted structural layers. Due to the electrical differences between the subgrade structural layers and the anomaly, single-trace instantaneous phase reversals occurred at 2 ns and 6 ns, which could be used to identify the upper boundary of the void defect. The boundaries and affected areas of the void defect could be identified through  
Figure 8: Loose defect instantaneous frequency features.  
Figure 7: Loose defect instantaneous phase features.  
the instantaneous phase image and the single-trace instantaneous phase variation curve in the GPR image.  
In the instantaneous frequency image (see Figure 10(a)), between the travel times of 8 and 30 ns, the cavity defect exhibited a hyperbolic-shaped instantaneous frequency response, with the opening facing downward. High-frequency reflection waves were seen mostly around 1000 MHz. When the electromagnetic wave reached the upper interface of the void, the reflection coefficient was positive. However, due to the minimal electrical difference between the void and the surrounding subgrade, coupled with the high propagation speed of the electromagnetic wave in the air, only low-frequency reflection waves were generated, making it difficult to accurately identify the posterior boundary.  
Figure 11: Cavity defect instantaneous frequency features.  
Figure 10: Cavity defect instantaneous phase features.  
Figure 9: Cavity defect instantaneous amplitude features.
# 5G Beyond 3 GPP Release 15 for Connected Automated Mobility in Cross-Border Contexts
## 2 5G Technologies beyond Release 15
### Network Slicing  
A vehicle may typically support multiple service/traffic types (safety-related and infotainment) associated with different uses cases where each one demands different levels of throughput, latency, reliability, robustness and so on. The different services may mapped to different standardised slice types optimised for the needs of each service. To that end, 3 GPP Rel-15 specified three slice/service types (SST) customised for enhanced mobile broadband (eMBB), ultra reliable low latency communications (URLLC) and massive IoT (MIoT) services [28]. The SST slices can be controlled by slice differentiator (SD) values for more granular slice definitions. In Rel-16, roaming support for mutually exclusive access slicing is planned [29]. Thus, slicing will improve roaming performance.
# Comprehensive Study of IoT Vulnerabilities and Countermeasures
## 2 Preliminary Materials
### Commonly Used Protocols
#### 2.7.16 Constrained Application Protocol (CoAP)  
The Constrained Application Protocol (CoAP) is a lightweight M2M binary protocol with a fixed header of 4 bytes and small message payloads from the IETF CoRE Working Group designed for constrained IoT devices. It supports both request-response and resource-observe architectures and can be used to interoper with HTTP and the RESTful Web API [54]. CoAP uses UDP as a transport protocol and DTLS for security, making it efficient for use on low-bandwidth and unreliable networks. It is designed to be as lightweight as possible, making it suitable for use on constrained devices with limited resources [52].
## 5 Discussion
However, the benefits of using smart contracts in international settings are substantial enough to make it feasible to overcome the aforementioned challenges, particularly in enhancing coordination among diverse geographical entities. By automating transactions and maintaining an immutable record of supply chain events, smart contracts can simplify the complexities involved in international logistics, such as customs clearances and freight tracking. This automation not only reduces the time and costs associated with manual processing [41] but also minimizes the risk of errors and fraud, thus fostering a more efficient and secure global trade environment. Further research could explore the integration of multi-language support within smart contracts to cater to international participants, enhancing understanding and accessibility. Moreover, future studies should examine the impact of geopolitical factors on the stability and reliability of decentralized systems like Ethereum. As nations vary in their technological infrastructure, exploring decentralized applications' performance in lower-bandwidth environments could be crucial for their broader adoption. In conclusion, the proposed supply chain management system offers transparency, accuracy, and automation benefits, but its successful implementation requires tailoring to the unique needs of the individual supply chains and parties involved. Configurable smart contracts and careful consideration of specific supply chain requirements are essential for effective deployment.
# Cutting Force When Machining Hardened Steel and the Surface Roughness Achieved
### Surface Quality Measurement by Non-Contact Method  
The evaluation of the surface quality of the functional surface by the non-contact method was carried out on the Alicona Infinite Focus G5 (hereafter referred to as Alicona). It is a highly accurate, fast and flexible optical 3D measurement system. The 3D measurements were made with Focus Variation. Focus Variation combines the small depth of focus of an optical system with vertical scanning to provide topographical and color information from the variation of focus [23]. The main problem of optical instruments is that most existing roughness standards are relatively smooth and can hardly be measured with several optical instruments [24]. The main component of the system is precision optics containing various lens systems that can be equipped with different objectives, allowing measurements with different resolutions [23]. With a beam splitting mirror, light emerging from a white light source is inserted into the optical path of the system and focused onto the specimen via the objective [24]. Depending on the topography of the specimen, the light is reflected into several directions as soon as it hits the specimen via the objective [23]. If the topography shows diffuse reflective properties, the light is reflected equally strongly in each direction [23]. In the case of specular reflections, the light is scattered mainly in one direction [23]. The main disadvantage is with the reflectivity of some surfaces, which means that more lenses and measuring conditions are required [7; 8]. The Alicona is a highly accurate, extremely fast and flexible optical 3D micro-coordinate measurement system for both form and roughness measurement, with a vertical resolution of down to 10 nm [21]. This measuring device is ideal for most precise surface analyses on homogeneous as well as mixed materials, and the system produces exact topographic information in true colors using vertical scanning and a shallow depth of field [21]. The Laboratory Measurement Module 6.6.1 was used for measuring the surface roughness parameters [25].  
The measurements were carried out under the following conditions:  
* Using a 50\(\times\) lens;
* Filter was Lc [\(\mu\)m] 800;
* Profile measurement path length [mm] was 4.
# Study on Impact Process of a Large LNG Tank Container for Trains
## 2 Experiment Measurement
### Impact Strength Test  
The impact strength test was conducted in accordance with the Chinese standard TB/T1335-1996 Strength design and test certification specification for railway vehicle to determine whether the frame meets with the strength requirements. Water, foam, and rigid fixed supports were used as the filling medium, where the foam and rigid fixed supports were used to guarantee that the center of gravity of water was consistent with that of LNG of the same mass. The impact vehicle with MT-2 buffers slid down the hill and then hit the stationary, non-braking transport vehicle with the tank container for the test and MT-2 buffers. The impact vehicle was driven three times at each of the following velocities: 4 km/h, 5 km/h, 6 km/h, 7 km/h, and 8 km/h. The twist lock fixed to the transport vehicle then collided with the corner fittings of the tank container after the impact vehicle collided with the transport vehicle. The two vehicles eventually traveled in the direction of the rail after being linked by buffers. The impact test scheme and the field test are shown in Figure 2.  
\begin{table}
\begin{tabular}{c c c c} \hline
**Item** & **Value** & **Item** & **Value** \\ \hline Specified filling rate & 90\% & Material of the 8 support rings & GFRP \\ Design pressure of the inner vessel & 0.6 MPa & Material of the inner vessel & S30408 (solution treatment) \\ Design temperature of the inner vessel & \(-\)196 \({}^{\circ}\)C & Material of the outer vessel & 16 MnDR (normalizing) \\ Design pressure of the jacket & \(-\)0.1 MPa & Material of the frame & Q450 NQRI (normalizing) \\ Design temperature of the jacket & 50 \({}^{\circ}\)C & Corrosion allowance & 0 \\ \hline \end{tabular}
\end{table}
Table 1: Main design parameters of the tank container.  
Figure 1: Schematic diagram of the tank container.  
To measure stress, several strain gauges were installed on the tank container, particularly on the frame. When the impact vehicle's initial velocity is 6.1 km/h, it is discovered that measuring point A28 on the longitudinal beam, near the corner fitting of the impact side, as shown in Figure 3a, has the largest compressive stress, with a maximum value of \(-366.3\) MPa and a direction parallel to the impact direction. The variation in the stress at A28 over time is seen in Figure 3b. It can be seen that the impact has a significant effect on the frame, which lead to a peak compressive stress at A28. The impact vehicle's collision effect is continually weakened as a result of the continuous energy consumption of MT-2 buffers, and the stress fluctuation at A28 decreases gradually.
## 4 Experimental Results
### Performing the Algorithm and Accuracy Assessment  
To measure the performance of Pan sharpening results using the metrics that were presented in Section 3.3, the Wald protocol was used, due to lack of reference a high-resolution MS image [53]. According to Wald protocol, all Pan sharpening experiments were done using degraded datasets, which are produced by decreasing spatial resolution of the original dataset (reduce MS and Pan, respectively, to 8 m and 2 m). The Pan sharpening results obtained that way, can be compared with the original MS images for an accuracy assessment procedure. In this paper, six Pan sharpening methods and eleven accuracy indexes are evaluated to perform a comparative accuracy assessment of the proposed method. The numerical results of the accuracy indexes are presented in Tables A1-A6. The visuals belonging to Pan sharpening results of ten frames are presented in Figures A1-A10. In each figure, parts a and b are the original Pleiades MS and Pan images, respectively. Parts c, d and e are the Pan sharpened results from the CIElab, GIHS and GS methods, respectively. The Pan sharpened images from the HCS, IHS, NNDiffuse and Ehlers methods are shown in parts f-i, respectively.
# Aerostat-Based Observation of Space Objects in the Stratosphere
## 4 Observation Ability Analysis  
Referring to the analysis for space-based optical observations [21], the observation ability of the telescope with the same aperture located in the stratosphere is 2\(\sim\)3 mag higher than that of the ground-based telescope. Taking a telescope with a field of view (FOV) of 20\({}^{\circ}\)\(\times\) 20\({}^{\circ}\) and an aperture of 100 mm as an example, four telescopes located in the aerostat pod can form an optical array with a huge observation field of about 1500 square degrees. In this way, rapid wide-area surveys of space object observations can be carried out in near space. If equipped with a stabilized steerable mount, this optical array can also track and monitor threatening events, such as dangerous close approaches and large space debris reentry.
## 3 Results and Discussion
### Verification of Model  
Validity of those three extraction models--i.e., Equations (9), (12) and (15)--have been evaluated by comparing with the experimental data. In order to verify the accuracy of the proposed extraction models, further several experiments were carried out at different process parameters. In these experiments, to ensure accuracy of the experimental results, each experiment was repeated three times and the average values were used. Table 4 listed the relative deviation (RD) between predictive values and experimental values. It could be seen that the average of RD showed a low range from 0.96% to 4.36%. The maximum values of relative deviation of ultrasonic power, ultrasonic frequency, and extraction temperature were 7.98%, 8.21%, and 8.74%, respectively.  
Additionally, Figure 10 depicted the experimental and model prediction of glycyrrhizic acid concentration. In all the considered cases, as can be seen, there was a good agreement between the experimental data and simulated trends. These satisfactory fits indicated that the developed extraction model could be used for better describing and predicting the ultrasonic extraction process of glycyrrhizic acid from _Glycyrrhizic uralensis_.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**Ultrasonic Power**} & \multicolumn{3}{c}{**Ultrasonic Frequency**} & \multicolumn{3}{c}{**Extraction Temperature**} \\ \hline \(P\) & \(\mathbf{RD_{max}}\)\({}^{\mathbf{a}}\) & \multicolumn{2}{c}{**The Average**} & \(f\) & \(\mathbf{RD_{max}}\) & \multicolumn{2}{c}{**The Average**} & \(T\) & \(\mathbf{RD_{max}}\) & \multicolumn{2}{c}{**The Average**} \\ (**W**) & **(\%)** & **of RD \({}^{\mathbf{b}}\) (\%)** & **(kHz)** & **(\%)** & **of RD (\%)** & **(\%)** & **of RD (\%)** \\ \hline
20 & 6.25 & 1.25 & 20 & 5.54 & 2.02 & 20 & 5.22 & 1.88 \\
50 & 3.09 & 0.96 & 30 & 5.98 & 3.36 & 25 & 4.31 & 1.97 \\
75 & 5.62 & 2.37 & 40 & 7.69 & 4.36 & 35 & 8.74 & 4.21 \\
100 & 7.98 & 3.66 & 55 & 4.33 & 1.85 & 60 & 6.32 & 2.65 \\
125 & 4.65 & 1.99 & 90 & 8.21 & 4.05 & 70 & 3.10 & 1.02 \\ \hline \hline \end{tabular}  
* RD\({}_{\text{max}}\) is the maximum of relative deviation; \({}^{\mathbf{b}}\) RD is the relative deviation.  
\end{table}
Table 4: The relative deviation between predictive values and experimental values.  
Figure 9: The equilibrium concentration (\(C_{e}\)) of glycyrrhizic acid, and integrated influence coefficient (\(\lambda\)) with different extraction temperatures.
# Research on Tracking Control of Urban Rail Trains Based on Improved Disturbance Observer
## 5 Conclusions  
In this paper, an IDOBC method is proposed for position and speed tracking control of the URTs under a multiple point-mass model, which can ensure the safe and stable operation of the URTs under unknown external disturbances and partial actuator failures. An improved disturbance observer is designed for the disturbance estimation compensation problem, and the estimation performance of the disturbance observer is demonstrated theoretically. The Lyapunov theory is used to analyze the stability of the train closed-loop system, and the linear matrix inequality gives sufficient conditions for the existence of the controller gain matrix. By comparing with the TDOBC approach, the simulation results show that the IDOBC strategy:  
1. It exhibits higher tracking accuracy in terms of displacement and velocity, and the tracking error is in the range of \([-7.8091\times 10^{-4},2.7326\times 10^{-4}]\) m and \([-0.0035,0.0018]\) m/s, which meets the punctual operation requirement of the UTRs.
2. With a smaller coupler displacement, which meets safety specifications and ensures safer train operation.
3. With stronger anti-disturbance capability, the error converges to zero faster after suffering external disturbance, which can make the URTs have better tracking performance. In addition, the coupler position is closely related to the safe operation of URTs. Although the control method proposed in this paper ensures that the coupler position remains within a safe range, there is still a risk of exceeding the safety limit. Therefore, on the basis of this paper, considering the coupler displacement constraint will be the subsequent research direction.  
Conceptualization, Y.Z. and J.Z.; methodology, Y.Z. and J.Z.; software, J.Z.; validation, H.Y.; formal analysis, Y.Z.; resources, H.Y.; writing--original draft preparation, Y.Z.; writing--review and editing, Y.Z. and J.Z.; supervision, H.Y.; funding acquisition, H.Y. All authors have read and agreed to the published version of the manuscript.  
This research was funded by National Natural Science Foundation of China (U2034211), the Technological Innovation Guidance Program of Jiangxi Province (20203 AEI009), the Graduate Innovative Special Fund Project of Jiangxi Province(YC2022-s484).  
Not applicable.  
The authors declare no conflict of interest.
# An Improved Adaptive Iterative Extended Kalman Filter Based on Variational Bayesian
## 1 Introduction
Initially, the inverse Wishart (IW) distribution is utilized to model inaccurate measurement noise, treating the system state and measurement noise covariance as parameters to be estimated. To estimate these parameters, the variational Bayesian (VB) method computes the joint posterior probability density functions (PDFs) for these parameters, thereby accomplishing the state estimation of the system. This approach effectively addresses variability in both noise and prediction error covariances. The algorithm exhibits the following highlights:  
(1) The approach is characterized by a notable insensitivity to its parameters, possessing the ability to withstand variations in parameter values. (2) The approach exhibits lower computational complexity, rendering it suitable for real-time applications. (3) This approach exhibits significant adaptability and reliability when confronted with an uncertain environment. The algorithm proposed in this article adeptly addresses the challenge of concurrently managing noise fluctuations and prediction error covariance in the state estimation process. When compared with two optimized algorithms, GA-VB [32] and RKF-ML [33], the performance of the VBAIEKF is notably impressive. Characterized by low sensitivity to parameters, minimal complexity, excellent convergence, and adaptability, these attributes render it a particularly promising solution for achieving precise state estimation in scenarios with heavy-tailed noise. The primary framework is outlined as follows. Section 2 delineates the procedural workflow of the VBAIEKF algorithm, where we deduce the filter and emphasize its unique characteristics. In Section 3, we conduct a thorough comparison between the proposed VBAIEKF and the GA-VB [32] and RKF-ML [33] algorithms. This comparison focuses on two-dimensional target tracking with nonlinear uncertain heavy-tailed noise and nonlinear numerical UNGM. The comparative analysis clearly demonstrates the superior performance of the VBAIEKF. Section 4 provides definitive remarks that summarize the findings and implications of the study.
## 3 Results and Discussion  
### Effects of the Various Portions of Added Pecan Nuts on Nutritional Composition  
The results of the nutritional composition of Merino lamb burgers enhanced with different amounts of pecan nuts in their formulation are shown in Table 1. The percentage of pecans added significantly affected the proximate analysis of lamb burgers (Table 1). Although protein content was similar (_p_ \(\geq\) 0.05), burgers containing pecan nuts had significantly higher (_p_ \(<\) 0.001) fat content and lower (_p_ \(<\) 0.001) moisture values than the control burgers. As expected, the fat content of lamb burgers increased as the pecan content increased and, in contrast, the moisture content decreased. These results are consistent with other findings relating to healthier frankfurters with walnuts added [34] and burger formulations, since pecan nuts are rich in fats with a high proportion of unsaturated/saturated fatty acids [35]. Similar results were observed by Reyes-Padilla et al. [36], who found an increase in fat content in low-fat bologna-type meat due to the addition of pecan nuts in their formulation.  
Protein content in all cases varied between 16.63 and 17.63 g/100 g of product, with no differences (\(p\geq 0.05\)) among batches. These values are slightly lower than the values typically found in lamb meat [37; 38]. Reyes-Padilla et al. [36] and Jimenez Colmenero et al. [39] obtained similar results on protein content (\(p<0.05\)) due to the addition of walnuts in low-fat bologna-type meat and restructured beef steaks, respectively, since they did not find variations in protein content, although the reported protein values are slightly higher than ours.  
The addition of pecan nuts to burgers gradually increased (\(p<0.001\)) the total phenol content with respect to the control burgers. Reyes-Padilla et al. [36] also reported an increase in phenol content in low-fat bologna-type meat enhanced with pecan nuts in their formulation. Pecan nuts are a rich source of polyphenols [40]. The phenolic compounds from walnuts and pecans could be beneficial because they scavenge free radicals (superoxide and hydrogen peroxide), and therefore have anti-inflammatory properties and prevent lipid and protein peroxidation [41].  
The lamb burgers with pecan nuts proved to have a lower caloric value than the control burgers (\(p<0.01\)). The decrease in caloric value was directly proportional to the increase in the amount of pecan nuts in the formulation.