esa-sceva/satcom-chunk-collection huggingface dataset:
## 6 Conclusions and Future Work  
There are many benefits in shifting focus from test automation at the implementation level to business-level, example-based specifications. The specifications are much easier to maintain and evolve. They can be used in an agile approach to development, supporting collaboration, communication and understanding among the wider team early in an agile iteration (\"what the system should do\" as well as \"how\"). They serve as trustworthy documentation of the business view of the system. They help ensure that work is completed, and that existing functionality has not been broken. They enable faster testing for faster feedback, and they can serve to guide brand new developments of old systems.  
Our work aims to support the process of refactoring implementation-level tests to business-level specifications. Given that repetition occurs across many implementation-level tests in a suite, our tool quickly provides feedback on possible points of abstraction. The user can focus the abstraction process by selecting parts of tests, and _ZiBreve_ will suggest possible abstractions and apply them. We have illustrated this cyclic process with browser-based tests for a web application.  
Once business rule tables have been extracted, our tool supports the analysis of the test cases, providing feedback on redundancies, inconsistencies, and possible incompleteness.  
Once the tests have been refactored to specifications, a focussed and effective domain-specific language should have been created. This can then be used directly in future evolution of the system, with _ZiBreve_ supporting the corresponding evolution of the domain-specific language where needed.  
We have also been considering systems that lack automated tests entirely. We have just added a variant of record-and-playback to _ZiBreve_, which incorporates abstraction as a part of the process. This allows tests to be recorded, but at a higher-level, resulting in business-level, example-based specifications, rather than implementation-level test scripts. We believe that this will be an effective way of dealing with \"legacy\" systems (those without test automation [21]).  
Given that example-based specifications serve both as detailed requirements specifications and as automated tests, it is interesting to consider other uses. We are well underway on supporting the generation of user-level documentation from example-based specifications. The mapping from business level to implementation makes it possible to describe what is going on at multiple levels, and to incorporate screen shots from the implementation level.  
Some tests, such as for web services, incorporate large amounts of semi-structured data such as XML, JSON, or YAML. Such data is not currently handled in our abstraction process, which focusses on abstracting actions. We plan to use a variation of our current algorithms for searching for potential abstractions across such data.
# Real-Time 3D PET Image with Pseudoinverse Reconstruction
## 4 Discussion
Moreover, for real time applications, most often, only projection images into predefined planes will be needed. This projection operation can be incorporated into the pseudoinverse array before reconstruction, drastically reducing the size of the matrices needed as well as the reconstruction time as shown in Figure 12 and Table 5.
### Results and Discussion of the Weighted Analysis
Case Scenario 5 introduces the concept of economic and social aspects being twice as important as environmental considerations (weights of 40%, 40%, and 20%, respectively). This results in outcomes very similar to those of Case 4. In this scenario, the natural system with atriums and courtyards again emerges as the highest-rated option, with the \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Scenario 1** & **Scenario 2** & **Scenario 3** & **Scenario 4** & **Scenario 5** \\ \hline
**N-SSV** & 0.218 & 0.165 & 0.184 & 0.203 & 0.205 \\ \hline
**N-CRV** & 0.230 & 0.188 & 0.203 & 0.219 & 0.221 \\ \hline
**N-AAC** & 0.236 & 0.198 & 0.211 & 0.225 & 0.227 \\ \hline
**H-NMR** & 0.131 & 0.141 & 0.140 & 0.136 & 0.131 \\ \hline
**M-CVS** & 0.186 & 0.308 & 0.262 & 0.217 & 0.216 \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Assessment of each ventilation system. Figure 2: Graphical assessment of each ventilation system in accordance with the given case scenario. centralized mechanical ventilation system in third place. This can be attributed to the fact that, in this case, M-CVS scores the lowest in both economic aspects of initial cost and maintenance. However, N-AAC stands out among the four alternatives because, on the one hand, along with the other two natural systems, it achieves the highest scores in economic and environmental aspects, and on the other hand, it obtains intermediate scores in thermal comfort during summer, consistently surpassing those of N-VUL and N-CRV. It is noteworthy to mention the sensitivity of the results to changes in weightings. This indicates that the choice of strategy may vary depending on the criteria and preferences of decision-makers. Thus, it is not possible to universally designate an optimal strategy. Furthermore, it is important to explain the results obtained by the hybrid system based on natural ventilation with mechanical recirculation (H-NMR), as they are not as favorable as one might expect. This is attributed to the simplification hypothesis presented in the previous section, which penalizes hybrid operations. However, the results do not imply that this operation should be dismissed. On the contrary, in certain circumstances, such as when the goal is to enhance summer thermal comfort with a relatively low investment, H-NMR represents an optimal solution, as indicated by the second indicator of the social requirement. Additionally, in a conceptual framework where ventilation operations can be combined and continuous operation is not necessary, H-NMR could significantly improve the outcomes. For instance, in a winter context, mechanical recirculation could be halted, leading to a more favorable assessment of thermal comfort by solely using N-VUL.
# Analysis of the Dihedral Corner Reflector's RCS Features in Multi-Resource SAR
## 3 The Novel Dihedral CR and SAR Data Set  
### The Novel Dihedral CR Design and Location  
The Huangtupo slope, located in Badong city, Hubei province, China, was designated as a national field scientific observation and research station by the Ministry of Science and Technology in 2020. Since 2019, Wuhan University and China University of Geosciences (Wuhan) have collaborated to install over 20 artificial corner reflectors with varying tilt angles and panel sizes on the Huangtupo slope, as depicted in Figure 3. These CRs are mounted on pre-constructed cement piers, and their coordinates are accurately measured using GNSS with a centimeter-level. The orientation of the CRs is accurately aligned with the satellite heading angle utilizing GNSS directional instruments by PandaGNSS company in Wuhan, China.  
Figure 2: (**a**) The schematic diagram of the RCS increase caused by the CR’s side length. (**b**) The RCS reduction curve caused by the CR’s deviation angle.  
This article introduces a novel dihedral CR (illustrated in Figure 4), with its core component being a trapezoidal connecting platform (refer to Figure 4b,d). The angles of the trapezoidal platform are specifically designed to align with the heading direction of SAR satellites, while the inclinations on both sides are designed to match the SAR local incidence angle. Its symmetrical structure enables observation from both ascending and descending satellite orbits.  
Taking the example of a dihedral CR with a semicircular panel with a diameter of 0.6 m, as illustrated in Figure 4a, the bottom semicircular panel is inclined at 15\({}^{\circ}\) with respect to the horizontal plane. The central axis of the CR aligns with the SAR local incidence angle of 30\({}^{\circ}\), resulting in the trapezoidal platform sides being inclined at 75\({}^{\circ}\). In Figure 4c, a dihedral CR with a square panel whose side length on each side is 0.4-m is depicted, specifically designed for a SAR satellite with a 45\({}^{\circ}\) local incidence angle.  
Figure 3: **(a)** The schematic diagram of the Sentinel and TSX data coverage test area; (**b**) the schematic diagram of the Huangtupo slope area and the location of the CRs; (**c**) the photos and installation time of multiple types of corner reflectors.
# Stress Analysis and Spalling Failure Simulation on Surrounding Rock of Deep Arch Tunnel
## 3 Simulation of Spalling Failure
### Test Results
Particle ejection occurred again at the original failure location on the left and right sidewalls. As shown in Figure 8d, the failure pit at the middle-left sidewall extended deeper, producing more pronounced extensional cracks and flexural bulging of rock fragments. At the moment, between 1313 s and 1377 s, through cracks can be found at the bottom of the sidewalls. When the vertical stress was continuously increased to 69.6 MPa, a large bulge of rock fragments was produced between the cracks running through the bottom and middle of the straight sidewall. Figure 8f shows a rock piece from the left sidewall, with the bottom of the straight sidewall buckling upwards. In view of this, the vertical stress \(\sigma_{\mathrm{Z}}\) and horizontal stresses \(\sigma_{\mathrm{X}}\) and \(\sigma_{\mathrm{Y}}\) were rapidly released to 0 MPa. The spalling failure process on the sidewalls of specimen A14-17.3-28.9 is shown in Figure 9. At 793 s, \(\sigma_{\mathrm{Z}}\) = 58.5 MPa, and a small particle ejection occurred at the middle of the arch foot on the left sidewall. After 39 s, a bulge occurred near the location of particle ejection. The bulge subsequently extended to both sides, and the particle ejection occurred again within a short time (Figure 9a,b). Figure 9c shows that at 872 s, the \(\sigma_{\mathrm{Z}}\) reached 60.1 MPa. The vertical stress was kept constant, and spalling occurred frequently on the left sidewall at this phase. The vertical stress was increased to 62.0 MPa at 961 s, as shown in Figure 9d. A small particle ejection also occurred at the bottom of the right sidewall in the middle of the hole, indicating that the energy accumulated in the right arch foot was released. As Figure 9e shows, with an increase of 1.0 MPa in the vertical stress, a flake with topple tendency is produced at a location symmetrical to that of the left bulging and spalling. Subsequently, a sharp spalling occurred on the sidewall during loading, accompanied by a large spalling area. This indicates that through cracks are produced from the free surface of the hole to the outside. Finally, an instability or sinking of the specimen occurred, and no longer displacement was produced. Figure 10 shows the actual failure of deep engineering structures. Combined with Figures 7-9, it can be seen that the reproduced failure is similar to the surrounding rock spalling at in-situ deep engineering, indicating that the simulation test is reasonable and valid.
## Combined Predictive Models  
### Empirical Modal Decomposition  
Empirical modal decomposition decomposes a complex signal into a sum of multiple intrinsic modal components based on the assumption that any complex signal is composed of multiple distinct components (IMFs) [15]. The core idea of the algorithm is to decompose the complex raw data into a finite number of intrinsic modal functions (IMFs) and residual signals that contain all the fluctuation information of the raw data on the corresponding time scales. Each IMF component must satisfy the following two conditions: the number of poles and the number of cross-zeros are the same or, at most, not equal to one, and the upper and lower envelopes of the component are locally symmetric about the time axis. In this way, any signal can be decomposed into a finite number of IMF sums, and any signal can be decomposed using the EEMD method on this basis. IMFs can be \"filtered\" as follows:  
All local maxima of the signal are found; moreover, all local maxima are connected with three splines to form the upper envelope. All local minima are connected with three splines to form the lower envelope, and the upper and lower envelopes should include all collected data points. The average of the upper and lower envelopes is noted as \(m_{i}\), \(x(t)-m_{i}=h_{i}\). Ideally, if \(h_{i}\) is an IMF, then \(h_{i}\) is a component of \(x(t)\). If \(h_{i}\) does not qualify as an IMF, use \(h_{i}\) as the original data and repeat the above steps to obtain the mean of the upper and lower envelope \(m_{i}\), and then determine if it qualifies as an IMF. If not, continue to repeat \(k\) times until the conditions in the IMF are met: \(h_{i-1}(k)-m_{i}k=h_{i}k\). Denote \(c_{1}=h_{1}k\), which is part of the signal that meets the IMF condition. The process of decomposing \(c_{1}\) from \(x(t)\) is shown in Equation (1).  
\[r_{1}=x(t)-c_{1} \tag{1}\]  
From Equation (1), after decomposing \(c_{1}\), the above process continues to be repeated using \(r_{1}\) as the original data until \(x(t)\) satisfies the second component of the IMF condition \(c_{2}\). The cycle is repeated \(n\) times to obtain the second component of the signal that satisfies the IMF condition \(x(t)\).  
\[\left\{\begin{array}{l}r_{1}-c_{2}=r_{2}\\ \ldots\\ r_{n-1}-c_{n}=r_{n}\end{array}\right. \tag{2}\]  
\[x(t)=\sum_{i=1}^{n}c_{i}+r_{n} \tag{3}\]  
From Equation (3), we conclude that the loop ends when it becomes a monotonic function from which no more components satisfying the IMF condition can be extracted. When \(r_{n}\) is the residual function, it expresses the average trend of the signal. Any signal \(x(t)\) can be decomposed using empirical modal decomposition to obtain the IMF component and the residual component \(r_{n}\).
## 2 The LEO Environment: Drag, Momentum Buildup (Aerospinning), and Meteoroids
A plot of minimal initial tip speed of a hanging tether is shown in Figure 6.  
In 2005, [PERSON] [25] stated that a stationary solution for the tether tip argument in elliptic orbits does not exist, and a tether tip must librate as the gravity vector is rotating non-uniformly. Therefore, for elliptic orbits, the minimal rotation speed is reduced compared to circular orbits. This finding was also partially supported by a study of [PERSON], the results of which were published in 2003 [18]. Micrometeoroids and orbital debris (MMOD) hazards play an important role in tether design. The colliding objects frequency on LEO can be extracted from Figures 7-19 in [24] and approximated by Equation (2) for debris ranging from 4 \(\,\mathrm{\SIUnitSymbolMicro m}\) to 2 cm in size. The collision probabilities are as summarized in Table 1.  
\[N_{\mathit{year}}=1.6\cdot 10^{-10}D^{-2.56} \tag{2}\]  
Figure 2:0 The minimal nadir speed of the tether tip relative to the tether center of mass to sustain tether rotation. Although, in 1995, [PERSON] and [PERSON] [26] claimed a redundancy of the fail-safe tether (hoytethers) may be implemented without sacrificing the tensile strength, it is highly unlikely, given the extreme difficulty of producing lightweight coupling to the fibers with high tensile strength. Couplings in damaged hoytethers would subject redundant filaments to the compressive stress. All high-strength fibers are weak in compression (with typical tensile-to-compression strength ratios being 10-40 [27]. Fatigue strength of filaments may be degraded as well, because zones of compression are a likely place for cracks to nucleate. Therefore, contrary to the conclusion of [PERSON] and [PERSON] [26], the failures of individual filaments in single hoytether segments may be correlated. As such, stated increases of redundant tether (hoytether) lifetimes may be not achievable, although further experiments are necessary to validate or reject such a claim. An alternative, an advanced form of a Whipple shield (stopping 6.3 mm particles for 10.8 kg/m\({}^{2}\) weight already flown [28]) may be better suitable for higher-diameter tethers. The stuffed Whipple shield (multishock shield) model with multiple layers spaced by 1.8 mm and a weight of 0.4 kg/m\({}^{2}\) per layer was integrated into software used to generate the sample mission budgets in Section 6.
## 2 Design of the Printed Patch Antenna  
For the experiment, a patch antenna with a coplanar dipole motif was selected [8]. The coplanar dipole was designed and optimized from an original cross-monopole design [9]. The original type of antenna stood out for its broadband capability but was quite large. It was necessary to reduce the size of the antenna. Small antenna dimensions and shape were achieved by using the evolutionary optimization method, as presented later in this paper [9]. The same antenna was fabricated by two different methods and on two different substrates, with known parameters, and both antennas were compared with the 3D LDM-printed antenna to investigate the behavior of this 3D technology. For antennas of this type, the precision of the fabrication is very important, particularly the precision of the slot between the feed face and the ground face. This aspect of the technology was also investigated. In the etching method, a gap of 0.1 mm is already at the edge of production quality. To produce a miniature gap that would be in the tens of um would be very challenging from both a manufacturing and financial point of view. However, the required accuracy in the tens of um can be achieved using 3D LDM printing technology. This is a great advantage of 3D LDM technology.  
The antennas produced by conventional methods on standard RF substrates will be taken as a standard for comparison with the 3D-printed antenna (using LDM technology). Generally, a printed patch antenna consists of a conducting patch on one side of the dielectric substrate and a ground plane on the other side. In coplanar antennas, however, the ground plane is on the same side as the radiating patch. These antennas typically have a gain between 5 and 6 dBi. The selected coplanar dipole is shown in Figure 1.  
Patch antennas can be placed on the surface of airplanes, spacecraft, rockets, cars, on the walls of buildings, on the reverse sides of mobile phones, etc. The main disadvantage of such antennas is their narrow bandwidth and low power loading. However, by special techniques such as changing the shape of the patch, increasing the physical size of the antenna, or appropriate choice of power supply, the bandwidth can be increased [8]. In the following sections, some of the techniques and their effects on antenna performance are discussed in more detail.
# Jointly Optimize the Residual Energy of Multiple Mobile Devices in the MEC-WPT System
## 2 Related Work
The above methods are similar to ours, but we propose the joint optimization method to minimize system delay in a multi-layer system. Combined with the latest research findings, researchers began to focus on the close integration of WPT and MEC [23; 24; 25; 26]. The wireless multi-user MEC system composed of multi-antenna AP and multiple single-antenna users is studied, the downlink WPT and uplink wireless communication (used to computation offloading) are performed simultaneously on orthogonal frequency bands. Through joint optimization of task-offloading time, AP energy transmission beam formation, task-offloading size and CPU frequency, while taking into account the constraints on task completion time and user energy harvesting, the convex optimization problem is obtained. By leveraging the state-of-the-art optimization techniques, the optimal solution to minimizing the overall energy consumption of the AP is obtained in a semi-closed form [22]. In [27], it is emphasized the MEC-WPT system of two mobile devices, and the two devices are at a far point and a near point, respectively. Fully considering the dual near-far effects of the distant mobile devices, the closer mobile devices cooperate in the form of the relay to perform offloading, and then according to the constraints of task-offloading to minimize the total AP emission energy. Finally, an effective problem form is obtained, and the two-stage method is used to solve the problem to get the best solution. The MEC system using multiple MDs and combined with WPT technology is studied, considering the goal of maximizing the remaining energy of MDs while ensuring more efficient energy collection efficiency and lower energy consumption. In the process of computation task and energy harvesting, the parameters are jointly optimized to maximize the remaining energy of the system and propose corresponding solutions to obtain the best solution [28]. The authors in [13; 29] extended the energy consumption minimization problems into multi-user MEC networks with TDMA and orthogonal frequency-division multiple access, respectively. Energy-efficient TDMA and non-orthogonal multiple access (NOMA) using partial offloading and binary offloading are studied in the wireless-powered MEC networks [30]. Regarding the previous research, most of the research focused on reducing energy consumption, which is a way of thinking for service providers rather than users. Only a few studies think about problems from the user's point of view, studying the remaining energy of MDs to ensure the user's service quality. Among them, most papers consider only one user in a time block is studied, but not the multi-user situation. The purpose of this article was to maximize the remaining energy in multiple time slots by studying multiple MDs in the case of time-division multiplexing and to ensure that the overall energy consumption is the minimum and the residual energy is the maximum.