esa-sceva/satcom-chunk-collection huggingface dataset:
## 5 Properties and Benefits of the Arrowhead-EP and the VCEP-Map
The Arrowhead-EP model can be adopted recursively to describe the final system but also the components and subcomponents (both hardware and software) that, following the SoS paradigm, compose the system. Arrowhead-EP workflows can be defined at different abstraction levels, depending on the purpose of the workflow, the role of the people involved, the toolchains, and the tools. The professional expertise and capabilities of the people involved in the EP represent a critical factor for engineering, and the Arrowhead-EP includes a specific phase focusedon professional _Training and Education_, covering all the figures involved in the EP: analysts, engineers, technicians, specialised operators, maintenance operators, and even the final user. The potential reduction in engineering costs is a direct consequence of a more automated and digitalised EP, which efficiently exploits modern IoT/SoS integration platforms, new tools, and integrated tool chains. Moreover, the engineering cost reduction potentially also originates from the improvement in the quality of the EP results indirectly because automation minimises the possibility of human errors. The Eclipse Arrowhead framework plays a fundamental role in automation managing EP execution. The Arrowhead-EP model, supported by the Eclipse Arrowhead framework, allows an efficient, secure, and simple sharing of EP information for all stakeholders involved in the system value chain and starting from the early stages of the EP. This has a potential positive impact on the engineering cost [61], confirming the strong innovation potential of the automation and digitalisation of the Arrowhead-EP. The approach proposed in this paper is supported by an existing and stable SOA/microservice framework, the Eclipse Arrowhead framework, which provides an architecture, appropriate tools and services required for the efficient digitalisation and automation of complex multistakeholder EPs. In the following, we list a summary of the major properties of the Arrowhead-EP and the VCEP-map when integrated into the Eclipse Arrowhead framework. 1. Information Feedforward and Feedback of information between engineering phases is supported. 2. Run-time engineering is enabled by the _Evolution_ EPP and property 1. 3. The engineering process can integrate information from multiple stakeholders. 4. Each engineering process phase can produce or consume more than one service. 5. The model is scalable to any number of EPUs. 6. The _Training and Education_ EPP provides education services to all other EPPs. 7. The automation of certain engineering tasks is supported, enabling the reduction of UC life cycle costs. 8. The EPs can be implemented by SOA/microservice-based implementation platforms. 9. Data security and privacy between stakeholders can be ensured through microservice AAA security. 10. Multiple use case EPs can be integrated through services. 11. The engineering workflow can be modelled at different abstraction levels.
## 3 Results
### Master Curves  
The master curves' complex moduli and phase angles of the 2S2P1D model for all UV-aged binders are given in Figure 7. It can be seen from Figure 7a,b that the 2S2P1D model can represent the complex modulus, but the phase angle test value is discontinuous. This shows that the asphalt binders after UV aging only meet part of the time-temperature equivalence principle, i.e., the viscoelastic causality between the viscoelastic parameters is not satisfied. However, compared with the black space diagram, the master curve can more clearly reflect the discontinuity of the viscoelastic parameters (such as the complex modulus and phase angle), i.e., the parameters of time-temperature failure. It can also be seen from Figure 7 that the complex modulus is a constant at low frequencies, and the main curve of the phase angle shows characteristics of a Wicket diagram, indicating that the asphalt still shows characteristics of a viscoelastic solid after different UV aging times. As  
Figure 6: Black diagrams of WB binders with various UV-aging times: (**a**) 3 days; (**b**) 6 days; (**c**) 9 days. seen in Figure 7, the aging times and the contents of nanoparticles had no obvious influence on the master curve of the complex modulus and phase angle of asphalt, indicating that the master curve is not very appropriate for evaluating the UV-aging process. The parameters of the 2S2P1D model for all UV-aged binders are shown in Table 1. The \(G_{0}\) values of all UV-aged binders are constant, indicating that nanoparticle-modified WB binders have characteristics of a viscoelastic solid. The \(G_{g}\) values obtained by [PERSON] et al. [28] vary from 0.9 \(\times\) 10\({}^{9}\) to 2 \(\times\) 10\({}^{9}\) Pa, and a value of less than 1 \(\times\) 10\({}^{9}\) Pa was used in this study. The \(k\) and \(h\) values for binders with various UV-aging times and contents of nanoparticles are almost the same and less than one, even though an evidently higher value of \(h\) is observed. The \(\alpha\) values for all UV-aged binders are higher than those obtained by [PERSON] et al. [22] in this study. The \(\tau_{0}\) values are related to the horizontal position for master curves. Moreover, [PERSON] et al. [22] pointed out that the parameter \(\beta\) is linked to the Newtonian viscosity of the model and has a large influence in this behavior domain. However, with the increase in aging time, parameter \(\beta\) of the 2S2P1D model has no obvious change. The goodness-of-fit of complex modulus is greater than 0.9 and greater than that of the phase angle. This shows that the master curves of the complex modulus gain better fitting in comparison with the phase angle curves for all UV-aged binders.
# Investigation of Debonding Effect in Internal Replacement Pipe System Under Lateral Loading
## 3 Surface Preparation and Its Impact on Debonding
### Behaviour of IRP System in 152.4 Mm (6 inch) Discontinuous Host Pipe
#### 3.2.2 Debonding Modes of Adhesive Layer  
Table 11 provides an overview of the debonding modes observed in the adhesive layer under varying loading levels and shear strengths of the adhesive. At the fatigue load, it was found that the 5 MPa (0.7 ksi) adhesive strength exhibited minor debonding. However, for the stronger adhesive strengths of 20 MPa (2.9 ksi) and 40 MPa (5.8 ksi), no debonding was observed. Under the maximum load, significant debonding was observed for the adhesive layer with 5 MPa (0.7 ksi) strength. In contrast, the adhesive layer with 20 MPa (2.9 ksi) strength showed moderate debonding. Remarkably, the adhesive layer with the highest shear strength of 40 MPa (5.8 ksi) remained intact without any observable debonding.  
Figure 29 illustrates the average debonded length of the adhesive layer at the maximum load of 56.9 kN (12.8 kip), comparing the debonded lengths across different levels of adhesive shear strength for the case of a 152.4 mm (6 inch) discontinuous system. The results show a substantially higher debonding rate associated with lower adhesive shear strengths compared with higher ones, with a ratio of 8.9 (slope 1 at 8.9 and slope 2 at 1.0), indicating that a decrease in adhesive shear strength results in increased debonding within the adhesive layer. Additionally, it is observed that there are no tangible benefits from excessively high shear strengths of the adhesive, as they do not significantly contribute to the bonding/debonding mechanism. For instance, no debonding is observed in adhesives with shear strengths exceeding 30 MPa (4.4 ksi).
## 5 Numerical Simulation Analysis of the Damage Rule of the Loose Layer  
### Numerical Model Construction  
The numerical model of particle flow was constructed based on the drilling cylinder of the working face of 20313 (Figure 9). The model is 174 m in height and 400 m in length. The model's boundaries are defined with fixed left, right, and bottom sides, while the top boundary remains free.  
Using \"PBM\" (Parallel Bonding Mode), the preliminary model is first established and brought to a state of static equilibrium under the influence of gravity. Once this balance is achieved, floating particles both inside and outside the model boundaries are removed. The stratigraphy of the working face is segmented into layers with specific mechanical properties [27, 28] (refer to Table 2) to precisely depict the characteristics of various rock and soil layers. The numerical model calculations are improved in efficiency and accuracy by optimizing the particle size, setting the particle radius between 0.3 and 0.8 cm. The force balance is recalculated until the unbalanced force ratio is reduced to less than \(10^{-5}\).  
The excavation of the working face is simulated from left to right, maintaining a distance of 20 m, with boundary pillars of 300 m on one side and 50 m on the other side of the model.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Number** & **Lithology** & **Thickness/ (m)** & **Density/ (kg/m\({}^{-3}\))** & **Young Modulus/ GPa** & **Poisson Ratio** & **Cohesion/ MPa** & **Internal Friction Angle** & **Modulus of Shearing/MPa** \\ \hline J1 & Gravel & 8.2 & 2800 & 39.6 & 0.23 & 0.52 & 36.0 & 832 \\ \hline J2 & \
\begin{tabular}{c} Red-bodied \\ weathered \\ sand \\ \end{tabular} & 4.1 & 2200 & 30.05 & 0.16 & 1.87 & 38.13 & 641 \\ \hline J3 & Loess & 5.8 & 2070 & 17.1 & 0.12 & 2.07 & 41.6 & 382 \\ \hline J4 &
\begin{tabular}{c} Black brown \\ loess \\ \end{tabular} & 2.6 & 2183 & 15.9 & 0.11 & 2.15 & 41.6 & 385 \\ \hline J5 & Drift-sand & 1.5 & 2155 & 24.0 & 0.15 & 0.01 & 38.13 & 520 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Macroscopic mechanical parameters of the loose layer.  
Figure 9: Numerical model of the overlying rock layer of the 20313 working face.
## 4 Experiments
### Setup  
Unlike the visual localization done using a single marker reported in [29], we have used ArUco markers map (AMM) for two purposes: one is for the identification of the kinematic parameters of each leg. The other is for the trajectory tracking of the robot. The advantage of using AMM over a single calibration grid or a single marker is that, with a single marker, it is impossible to always keep it in the line of sight of the camera. Figure 11 shows the printed markers from the ArUco library (ARUCO_MIP_36H12) [39; 40] on the flat boards.  
These multiple markers are distinct, and each having a dimension of 99.2 \(\times\) 99.2 mm was glued on the flat board. These markers were glued without any waviness on the board, which can cause the error in pose reading. The process required building a pairwise markers map database by taking the sequence of images with the common markers appearing in consecutive images using the calibrated camera. This database generated contains the relative pose of each marker concerning one another [29]. We placed the markers such that multiple markers (more than five markers) were visible in a single image or frame. This helped in achieving better pose estimation of the camera using an optimization that involved minimizing the reprojection error of markers in the observed frame [29]. Two approaches for using camera to make position measurements are presented in [41], namely, monocular camera [43; 44], and the other is stereo vision [42]. Stereo cameras allows direct pose measurements, but it requires the processing of corresponding images which makes it computational expensive. Whereas, monocular camera usage for pose measurement is an area of research interest because of the following aspects: (i) Synchronizing the captured images taken from multiple cameras is not needed; (ii) Pose readings over a larger workspace can be taken in a region without bothering on the field of view of two or more cameras overlap; (iii) The space required for mount is reduced. Therefore, the use of a monocular camera for pose measurement for kinematic identification and a trajectory followed test is utilized.  
Some details of the approach during the experiments are worth noting. The experiments were carried out in ambient lighting conditions. For kinematic identification, the camera was mounted on the last link of a leg, and each joint was actuated one at a time. The frames were grabbed using the Chameleon3 camera from Pfgrey (FLIR Integrated Imaging Solutions Inc., Richmond, BC, Canada) [45] with the 10 mm fixed focal length lens attached to it at 40 frames per second. The position of the markers must not be changed after being placed for a given set of readings. By placing the markers in spread fashion over a larger area, it was possible to actuate the robot's joints in its full workspace as  
Figure 11: Flow diagram to obtain a pose from the calibrated camera using ArUco markers.  
shown in Figure 9b. The frame was grabbed using the camera, and the pose was obtained using the flow diagram presented in Figure 11. The evaluation of the measurement approach proposed here is presented next.
# Numerical Simulation of Vacuum Leak Jet and Jet Noise
###### Abstract  
With the explosive growth of space debris, collisions among space debris and spacecrafts seem to be inevitable, which may greatly threaten the structure of on-orbit spacecrafts as well as astronauts' safety. It is of crucial importance to locate the leak source and evaluate the corresponding damage quickly and accurately to ensure the safety of astronauts and spacecraft equipment. It is widely accepted that acoustic emission method can be used to detect on-orbit leak for space station; however, accurate prediction of vacuum leak noise in space station is difficult as jet and jet noise in vacuum environments are different from those in terrestrial environment. Therefore, this paper tries to investigate sound generations of vacuum leak jet by numerically analyzing dynamics of unsteady vacuum jet flow. Specifically, numerical simulation based on realizable k-\(\epsilon\) model is adopted to study the aerodynamic properties and the aeroacoustic characteristics. Results show that RANS turbulent model can capture the pressure fluctuation with high computation efficiency and acceptable accuracy. Secondly, leak from 1 atm to vacuum forms a supersonic flow with Mach number ranging from 2 to 3, accompanied by obvious gradients of steady density, pressure, and temperature. However, the terrestrial leak from 2 atm to 1 atm forms subsonic jet flow with gradually varying gradients of density, pressure, and temperature. Thirdly, obvious reflections of pressure perturbations at the surface, with the mean free path of air molecule being 0.6 mm, can be found and form cavity-like acoustic resonance. Such resonant mechanism contributes to harmonic acoustic properties of the vacuum jet noises besides the broadband turbulent mixing noises.  
vacuum leak; supersonic jet; vacuum jet noise; acoustic cavity resonance; space station +
Footnote †: journal: Applied Sciences
# Influence of Polypropylene Fiber on Tensile Property of a Cement-Polymer Based Thin Spray-On Liner
## 1 Introduction  
### Development of Thin Spray-On Liners  
Thin spray-on liners (TSLs) are surface support materials that are sprayed onto the rock surface at a layer of 3 to 5 mm thickness [1]. TSLs (reactive or non-reactive) are generally cement, latex, and polymer-based. The first tests on TSLs were performed in Canada in the late 1980s. Initial research yielded a polyurethane-based product. Afterward, researchers from South Africa began exploring the use of a latex-based TSL [2]. As a sealant, TSLs can reduce weathering fretting, the permeability of shotcrete, and the corrosion of steel supports. [PERSON] [3] investigated, via experiments, the potential use of TSLs for gas management in underground coal mines. Observations from users have indicated that TSL support performance has, in most cases, exceeded expectations [4; 5]. [PERSON] [1] has summarized the following advantages of TSLs:  
* Rapid curing rate and ability to reach adequate mechanical properties within a few hours after application;
* Low rebound amount and wastage during spraying process;
* Wide displacement range (elongation ratio);* Ease and rapid rate of application;
* Smaller spraying equipment than that required for other liners;
* Less material handling with respect to other ground support products;
* Decrease in the operating costs;
* Lower thickness of applied material with respect to other surface support systems.  
The mechanical performances of different TSLs have been determined worldwide, and of these the tensile performance is considered the most important. Nine support mechanisms have been summarized by [PERSON], and at least six of these depend substantially or completely on the tensile strength contribution from the liner [4]. Hence, tension-related testing has been one of the most commonly employed physical property testing methods of thin spray-on liner (TSL) products worldwide. Tensile strength tests were conducted by [PERSON] and 21 TSL products were categorized on the basis of tensile strength [6]. A practical guide of a cement-based TSL was provided after the tensile creep behavior of this TSL was investigated by [PERSON] [7]. The tensile toughness of TSL has been proposed as a new performance criterion for TSL, and various TSL energy absorption capacity values were determined [1].
###### Abstract  
At present, 5G base stations are densely distributed in major cities based on improving user concentrations and the large demand for services in urban hotspot areas. Moreover, 5G communication requires more accurate communication propagation loss (PL) monitoring. Low-build areas, such as suburbs and rural areas, are prone to forming relatively stable tropospheric ducts, which can bend the signal to the surface in the duct-trapping layer for multiple reflections. Due to the random flow of the atmospheric air mass, each reflection of the communication signal is re-scattered in the troposphere through the top of the duct layer, thereby expanding the propagation range of the signal and changing the expected effect of radio wave propagation. If ducting and troposcatter effects happen in the 5G base station antenna layer, co-channel interference (CCI) could occur, affecting the quality of electromagnetic propagation. Urban links in the plain area have no major terrain obstacles, but ground fluctuations and land cover scattering have a greater impact on the signal scattering at the bottom of the duct. On the basis of the forward-propagation theory, this paper adds factors, such as ducting the forecast value using real weather parameters, terrain, and land cover-type distributions to evaluate the CCIs of over-the-horizon communications on the intercity link. Based on 1300 sets of randomly generated terrains and landforms, two deep learning (DL) models were used to predict the PL of over-the-horizon communications between cities in a land-based ducting environment. The accuracy of LSTM prediction could reach 98.4%. The verification of PL prediction using DL in this paper allows for quick and efficient prediction of PL in the land-based ducting of intercity links using land cover characteristics.  
atmospheric duct; troposcatter; tropospheric turbulence; intercity co-channel interference; deep learning Article
## 4 Results
### On-Grid Operation
#### 4.1.1 Generating a Constant Power  
Measurements were carried out for several values of power generated in steady state. The results for the maximum power generated to the grid (about 20 kW) are presented below. The value of the active power generated to the grid is set in the controller just like the state of the contactor K1 (Figure 8), which is closed. The values of the currents and voltages (Figure 9) and the quality parameters of the electrical energy were measured in connection to the grid (Figures 10 and 11).  
For the Fluke manufacturer's stated measurement accuracies, the measured values are: (1) voltage of phase L1: 238.20 \(\pm\) 0.23 V; (2) current of phase L1: 27.6 \(\pm\) 0.6 A; (3) active power of phase L1: 6.56 \(\pm\) 0.1 kW.
# Coastal Zone Classification Based on U-Net and Remote Sensing
###### Abstract
Finally, we divided all features and the original spectral data into five groups, selecting each group as input for the best-performing classifier to test feature sensitivity. The experiments were conducted on GF-2 high-resolution data from Shuangyue Bay, a typical coastal zone in Guangdong Province.
# Multi-mode Microscopic Hyperspectral Imager for the Sensing of Biological Samples
## 3 Results
### Human Fingerprint Detection in Reflection Mode  
A similar scan imaging experiment was carried out to detect a human fingerprint under reflection mode. A light-emitting diode (LED) lamp was chosen as the broadband light source. The measured finger was fixed on the motion stage, and a total of 200 spectral images were captured with 20 s scanning time. To avoid possible touch and pollution between the finger and 40\(\times\) objective (0.6 mm working distance), reduce the difficulty of experimental operation, and increase the scanning FOV, we replaced the 40\(\times\) objective with a 10\(\times\) objective (RMS10X, 10.6 mm working distance, Olympus, Tokyo, Japan). The restored spatial image of the fingerprint was shown as Figure 4b. Due to the uneven surface of the finger itself, as well as the unconscious slight shaking during the scanning process, the restored image has some blur or distortion. However, some details can still be distinguished and we believe the result can still be used to demonstrate the feasibility of our system.  
We selected a ROI (marked as dotted circle) to study the reflection spectrum of the fingerprint. Two average reflection spectra of the ROI and a standard white plate (STD-WS,  
Figure 4: Experimental results for the hyperspectral detection of a human fingerprint under the reflection mode. (**a**) The reflection spectrum of the fingerprint. (**b**) The reflection spectrum of the standard white plate. (**c**) The hyperspectral image of the tested fingerprint. Scale bar: 500 μm. (**d**) The reflectance spectrum calculated by Equation (2) and the data in (**a**) and (**b**).  
China) were shown in Figure 4a,c, which were defined as \(\mathrm{R_{o}(\lambda)}\) and \(\mathrm{R_{w}(\lambda)}\), respectively. The standard white plate was used as the reference for reflectance. A reflectance spectrum was calculated using the following equation:  
\[\mathrm{R(\lambda)}=\frac{\mathrm{R_{o}(\lambda)-D}}{\mathrm{R_{w}(\lambda)-D}} \tag{2}\]  
where D was defined as dark noise, and was neglected in our calculation because it was weak. Figure 4d shows the reflectance spectrum of the fingerprint. We can observe two absorption bands around 535 nm and 570 nm, which stem from the absorption of oxygenated hemoglobin (HbO2) [22]. The values of reflectance provide a potential method for the qualitative assessment of the blood concentration, and a smaller numerical value refers to a higher concentration, indicating the MMHI system may be useful for biometrics applications.