esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 Basics of Gust Load Alleviation
### Gust Load Control Strategies  
As mentioned previously, flaps, such as ailerons, elevators or spoilers are normally used as the control surfaces for gust load alleviation. A complete gust load control system includes controllers, actuators and sensors. This control system is commonly called as Gust Load Alleviation (GLA) system. Sensors, such as air data sensors and accelerometers, are located on the aircraft body or wing to sense the incoming wind conditions and to provide feedback of dynamic loads. The general principle of gust load alleviation is to use sensors to provide motion feedback signals for the controllers. The controllers then initiate corresponding deflections of the control surfaces to create the aerodynamic forces and moments needed for attenuating the extra load induced by the gusts. Activating the control surfaces timely can determine the effectiveness of a GLA strategy. Detection of incoming gusts ahead of the aircraft to create a feedforward input is important. This provides control surfaces with additional time to respond. Currently, to compensate the lag of the control surface, it is common to locate the sensors ahead of the wings, along the fuselage, to provide the hydraulic actuators longer time to respond. A high-resolutiondirect-measuring short-pulse ultraviolet (UV) Doppler lidar system was designed and tested on an Airbus A340 [34]. It was shown that a forward detection range of 50 m of the atmosphere disturbances was achieved, which translates to a lead time of 300 ms for control surfaces to perform.  
Control methods can be categorized as either passive or active. Currently, the widely used gust load control system is active. Passive gust load control devices are more attractive as no extra energies are required compared to the active ones, and initial research has been conducted as being introduced in the following section. Open and closed-loop controls are commonly used by the GLA system. Closed-loop control utilizes feedback to compare the actual output with the desired output. For a successful closed-loop control system, the effective control laws [35; 36] play an important role. Various control laws for GLA system have been investigated, such as the linear quadratic regulator theory [37; 38], linear quadratic Gaussian method [39; 40], and optimal control algorithms [41]. As this article focuses on the overview of the flow control devices for gust load alleviation, the progress in the control laws will not be covered further here.
# Measures and Methods for the Evaluation of ATO Algorithms
## 3 Approach for ATO Testing
### Key Performance Indicators
Braking and acceleration values shall remain equal to or below \(1.5\frac{\text{m}}{\text{s}^{2}}\) to be considered comfortable. The proposed classification can serve as an indication of how to interpret the measured values. All defined values must be seen in the context of the concrete application. Note that comfort is only evaluated in terms of longitudinal motion. Mainly of importance to infrastructure managers is the capacity. To measure such a complex train operation performance indicator, it is necessary to define what capacity means in the context of the conducted investigations. In [40], capacity effects related to the introduction of ETCS are linked to a reduction of the train following times. This reduction increases the number of trains that can travel on one route within a given period, e.g., one hour. Because this approach is testing an ATO algorithm within a defined scenario and not by simulating a comprehensive railway network, simpler capacity indicators are chosen. The first indicator checks the compliance with given CTPs. When a train passes a CTP within its time window, the full (or intended) capacity is reached under the condition that the time window can be respected with a time-optimal drive. By comparing the actual and permitted speed (ETCS permitted speed curve), a potential to increase the speed driven on this section and thus to increase capacity can be identified. This way of identifying capacity potential was mentioned in [8] (Tests of ATO over ETCS by SBB), but not fully evaluated. As a second capacity indicator, the difference between both speed curves can be examined by calculating the area enclosed by them. Therefore, Equation (3) can be utilized to stepwise approximate this area. This value is then comparable to a reference value, e.g., from a drive under optimal conditions. \[A=\sum_{i=1}^{n}\left\{ \begin{array}{ll}(v_{\text{perm},i}-v_{i})\cdot\Delta t &(v_{\text{perm},i}-v_{i})\geq 0,\\ 0&(v_{\text{perm},i}-v_{i})<0.\end{array} \right. \tag{3}\]
## 4 Requirement Validation and Compatibility Analysis
### Case-Based Requirement Analysis
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Requirement** & **Test Type** & **Input** & **Output** \\ \hline \multirow{4}{*}{REQ\_01\_AdaptiveLight} & Conceptual & Beam adjustment sketches & Theoretically validated concept \\  & SiL & Simulated data: car in the opposite direction & Beam was adjusted without glare \\  & HiL & CAN signal from real camera & Response \textless{} 50 ms \\  & DT & Three-dimensional environment with & Correct beam adjustment \\ \hline \multirow{4}{*}{REQ\_02\_ElectricalFault} & Conceptual & Redundancy block diagram & Safety feature requirements \\  & SiL & CAN signal loss test & The system passes safely \\ \cline{1-1}  & HiL & Short circuit injection & The headlight deactivates in \\ \cline{1-1}  & DT & Cascade defect simulation &
\begin{tabular}{c} controlled mode \\ System impact analysis \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Progressive validation approach across Conceptual, SiL, HiL, and DT stages. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**REQ** & **Concept** & **SiL** & **HiL** & **DT** \\ \hline
1 & — & ✓ & — & ✓ \\
2 & ✓ & ✓ & ✓ & ✓ \\
3 & — & — & ✓ & ✓ \\ \hline \hline \end{tabular} \(\gamma\): Requirement is validated/covered in this stage. —: Requirement is not validated/not applicable in this stage.  
\end{table} 
Table 3: Distribution of validation requirements across concept, SiL, HiL, and digital twin. processes observed in current automotive development. The framework is, therefore, technically applicable in industrial contexts. Future work will focus on applying the method to empirical data obtained from actual headlamp system projects to further evaluate its robustness and integration potential. While this paper does not report experimental prototyping or implementation of a full case study, its primary objective is to define a reusable and transferable validation structure that integrates SiL, HiL, and DT methods. The validation logic--though presented in abstract form--is grounded in common industry practices, and a pilot application is planned in future work to strengthen the framework's empirical foundation.
# A Survey of Planning and Learning in Games
## Planning and Learning in Games
### Learning Applied to Planning
#### 5.2.2 Monte Carlo Methods  
Monte Carlo methods are learning methods that learn from experience either sampled from real or simulated interaction with the environment [95]. Particle Filters (PFs) [234; 235] are an example of this family of methods. PFs use a set of particles (or samples) to represent the probability density function (PDF) of the state of a stochastic system, which is iteratively refined via resampling. PFs can be used for example to solve dynamic state estimation problems, given partial or noisy observations.  
Examples of application of PFs in the context of games include the Partially Observable Monte-Carlo Planning (POMCP) [236] algorithm and POMCoP (Partially Observable Monte-Carlo Cooperative Planning) [237], its variant to create NPC sidekicks in cooperative games. Both algorithms combine PFs, used to update the agent's belief state, with MCTS, used to plan based on the current belief state. PFs also allowed both algorithms to be scaled to significantly larger POMDPs (Partially Observable MDPs) where planning successfully was previously not possible. In the case of POMCoP, planning in belief space (i.e., the space of probability distributions over possible configurations of the world) also allows the AI agents (NPC sidekicks) to reason about how their own actions affect their knowledge (i.e., their beliefs) about the intentions of the human player (or collaborator).  
Another example of an MC-based method is the MC Counterfactual Regret Minimization (MCCFR) algorithm. MCCFR was used to train Pluribus [238], the computer program that achieved above top human professional level play in six-player no-limit Texas hold'em poker, via self-play. MCTS (already presented in 4.1.3) is yet another example of a MC-based method.
## 3 Image Processing Approaches Used for EAT and PAT Segmentation
### Traditional Image Processing Techniques
#### 3.1.1 Thresholding CT Images  
The intensity values of CT scan's pixels are usually on a scale called the Hounsfield scale which is proportional to the attenuation of X-ray radiation of the tissue on that pixel [28]. Adipose tissue pixels have values between \(-250\) HU and \(-30\) HU [6]. This enables segmenting adipose tissue by thresholding the image, i.e., removing all pixels outside of a given range. Most papers mentioned in this review use thresholding at least in parts of their methods for segmenting EAT.  
Thresholding, however, can segment all adipose tissue but fails to segment only EAT. Most papers mentioned in this review try to segment the pericardium in some way, and then use thresholding or other means to segment adipose tissue contained by the pericardium, which they deem EAT. As discussed in Section 2, this corresponds to a commonly used definition of EAT, as well as the definition used by this review.
# Miniaturized MIMO Antenna Array with High Isolation for 5G Metal-Frame Smartphone Application
## 2 Proposed MIMO Antenna Design
### Decoupling Element  
We have experimented with several different decoupling techniques to improve isolation between each two antenna elements. Due to their inability to control the surface current on the metal frame, we find that few solutions work well with our design. In our design, the metal frame's surface current plays a major role in the coupling between two antenna elements.  
We separated the two antenna elements with a slot etched on the metal frame. At the same time, a groove is etched on the ground to cancel the coupled currents. In Figure 8a,b, the decoupling effect is clearly visible. Miniaturization is accomplished by making the decoupling slot's footprint as small as possible. The decoupling structures' ultimate size and shape have both been optimized, which is noteworthy.  
A C-shape slot with an area of only 0.0078 \(\times\) 0.047\(\lambda^{2}\) (\(\lambda\) corresponds to 4.7 GHz frequency) is etched on the back cover of the metal frame. A vertical I-shape with an area of 0.12 \(\times\) 0.004\(\lambda^{2}\) slot is engraved on the metal frame. The two grooves are connected with each other. The etched combination groove can block and confine the current on the upper surface of the metal frame, which can prevent the excited antenna's field from reaching the unexcited area.  
Figure 6: Simulation results with L1 and L2. (**a**): The reflection coefficients obtained after moving the feeding line to the left and right, respectively, and (**b**): the reflection coefficients obtained after moving the feeding line up and down, respectively.  
Figure 7: Transmission coefficients of MIMO antenna systems without decoupling.  
The surface vector current distribution without the decoupling slot and with the decoupling slot is compared, as shown in Figure 9, to verify the mechanism of the decoupling slot. According to Figure 9a,b, it is concluded that the combination decoupling slot effectively blocks the current excited by Ant 1 from coupling into Ant 2. By comparing Figures 7 and 10, it is evident that adding a decoupling slot improves the isolation from 13.5 dB to more than 22 dB, which is comparable to the latest technology in this field. Finally, four combination decoupling slots have been etched entirely to improve the isolation of four pairs of adjacent antenna elements. The size of the entire MIMO antenna system has been optimized. The optimized results are shown in Figure 2a.  
Figure 8: Surface current distributions when Ant 1 is excited. (a): Without decoupling structure and (b): with decoupling structure.  
Figure 10: Transmission coefficients of MIMO antenna systems with decoupling.  
Figure 9: Surface vector current distributions. (a): Without decoupling structure and (b): with decoupling structure of Ant 1 and 2.
# Quantification of the Benefits for Power System of Resilience Boosting Measures
## 5 Case Studies
### Quantifying the Benefits of Passive and Active Measures in Engineering Mode
#### 5.5.6 Effect of Active Measures (EM3-A1 and EM4-A2) for Wet Snow Scenarios  
Case EM3-A1 simulates the optimal reconfiguration algorithm to the N-2 outage of branches 40-41 and 16-19 found as a risky contingency in case EM3 which determines the LOL of several customers connected to the Rhemes Valley feeder.  
Table 8 reports the minimum MV voltage (M\({}_{\text{V}}\)), the percentage of restored load and the active power losses (p\({}_{\text{losses}}\)) obtained after applying any combinations of one or two switching actions: There is no \"one switching\" reconfiguration of a counterfeed (k = 1) which allows a full restoration of the disconnected load.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**State** & **M\({}_{\text{V}}\)** & **Percentage of Restored Load (\%)** & **Plosses. MW** \\ \hline
001 & 0.9951 & 66.67 & 0.0119 \\
010 & 0.9987 & 48.30 & 0.0087 \\
100 & 0.997 & 81.63 & 0.0125 \\
011 & 0.9951 & 66.67 & 0.0119 \\
101 & 0.9951 & 100 & 0.0156 \\
110 & 0.9975 & 81.63 & 0.0109 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Performance indicators for different counterfeed reconfigurations, outage of branches 40–41 and 16–19.  
Figure 11: (a) Mechanical tension in kN for medium voltage (MV) MV and high voltage (HV) lines, (b) Contributions to total risk of each contingency category, case EM4.  
The optimal reconfiguration algorithm looks at all the reconfigurations of two counterfeeds (k = 2). Only one reconfiguration with k = 2, (i.e., X\({}_{63-26}\) = 1, X\({}_{26-31}\) = 0 e X\({}_{12-46}\) = 1), allows restoring the unsupplied load with a minimum number of maneuvers, preserving also the radiality of the post-contingency network topology.  
In case EM4-A2 the OPF measure is applied on branch #53-#57 with a rated current of 70A, to attain increasing requirements in terms of minimum anti-icing current. The application of the minimum current constraint determines changes in typical network operating quantities such as high power counter-flows, low voltage at extreme branch node and on Primary Substation (PS) MV busbar (through OLTC tap position) as shown in Table 9.
# Development Workflow for Manifolds and Fluid Components Based on Laser Powder Bed Fusion
## 3 Case Study
### Conceptional Phase (Steps 2-4 of Development Methodology)  
At the beginning of the conceptual phase, the functional structure of the manifold is visualized. In addition to the primary hydraulic functionality, the manifold fulfills several further functions like the fixation of the assembly onto the vehicle, creating a sealing surface for the oil tank, and providing attachment points for the tank and electric cover. Once the functional structure is described, multiple conceptual solutions are introduced as to be seen in Figure 4. These solutions include only the main elements to create multiple concepts in a time-efficient manner. The topology optimized (TO) concept shown in (a) places all main elements within a TO frame structure, which may create a sufficient stiffness of the part, while large surfaces can be made of a thin wall. The L-shape concept aims to position all service components onto one side and takes advantage of a perpendicular orientation of valve elements. Lastly, concept three realizes a radial sealing for the oil tank which, in contrast to the existing flange sealing implicates improved sealing characteristics.  
Based on the introduced concepts, a value-benefit analysis regarding the evaluation criteria proposed in Section 2 is conducted (cf. Table 4). Weight reduction is most probable with concept a), whereas concept b) has the potential for short hydraulic channels. The build job profitability is rated by comparing them with each other. An analysis compared to the serial part was not conducted since the goal of the development study was to gain knowledge and experience with the AM workflow. An early evaluation is feasible with existing AM costs models, e.g., from [PERSON] et al. (2018). As a result, concept a) is recognized as being the most suitable concept for the boundary conditions of the project.
## 1 Introduction
### Related Work  
#### 1.2.1 AR-Based Maintenance Training Content  
AR-based maintenance training content has been researched in various fields to determine an efficient method of maintenance. A framework that forms a systemic procedure for railway vehicle maintenance was presented in the work of [5]. This framework provides the necessary data for a realistic maintenance situation. In addition, a case study targeting 28 participants demonstrated that this framework enhances the maintenance capabilities and skills of the operator. An aircraft maintenance manual that applied AR technology was presented in the work of [6]. This study's manual used the leakage procedure of a hydraulic valve as an example procedure. As a result, it proved that the manual improved maintenance efficiency. [PERSON] et al. [7] presented a system called Mantra, which was combined with AR technologies. They demonstrated the effectiveness of the system based on real use cases by comparing it with an existing method and applying the system to industrial maintenance. [PERSON] et al. [8] presented a bus maintenance system based on an AR system and wearable devices. They tested the system under actual operating conditions and demonstrated the excellent performance of the system. In addition, this system is convenient because it can be connected directly to the database server.
###### Abstract  
This study aimed to explore the relationship between change of direction deficit (CODD), change of direction total time (CODT), and linear sprint time and to compare the differences between CODD and CODT in assessing an athlete's change of direction (COD) ability. Forty-four highly trained male young athletes underwent Y-shaped pre-planned agility, Pro-agility, and 30 m linear sprint tests. The results showed a moderate to highly significant correlation between CODT and linear speed time at 0-5 m, 0-10 m, and 0-30 m (r = 0.5-0.8), while there was no statistically significant relationship between CODD and linear speed time at 0-5 m and 0-10 m (r = 0.0-0.3). CODD and CODT were moderate to highly correlated (r = 0.4-0.8), with CODD for 180\({}^{\circ}\) COD showing a higher predictive value for CODT compared to 45\({}^{\circ}\) COD (14-35% vs. 49-63%). Additionally, 13-22% of the participants showed opposing results for COD ability when comparing the standardized Z-score of Pro-agility 0-10 m CODT and CODD. Pro-agility 0-10 m CODD also resulted in a higher asymmetry ratio (2% vs. 7%) and COD ability imbalances (0% vs. 38%) than Pro-agility 0-10 m CODT. In conclusion, CODD may provide a more accurate assessment of an athlete's COD ability than CODT.  
change of direction deficit; change of direction; speed; test; athletes Article  
A Comparative Analysis of Change of Direction Deficit and Change of Direction Total Time. _Applied_  
3
## 3 Results  
### Resolution Target  
In a first experiment, the resolution target was scanned without using a mask. The intensity images and their simulation are shown in Figure 5 top and bottom row, respectively. The resolution is strongly frequency-dependent, as expected for the wavelength limited resolution \(d\) of such an optical setup given by  
\[d=\frac{\lambda}{2 NA} \tag{3}\]  
where \(NA\) is the numerical aperture and \(\lambda\) the wavelength. If we assume for our setup \(NA=0.14\), the resolution limits are estimated to \(d\) = 2 mm for 0.5 THz and \(d\) = 0.5 mm for 2.0 THz.  
Next, we looked at a configuration where the sample was positioned very close (\(\Delta z\) = 0.5 mm) to an aperture of diameter \(d_{\text{mask}}=0.5\) mm. Figure 6 shows the measured images in the top row and the simulated images in the bottom row. The resolution is much improved compared to Figure 5 and only slightly frequency-dependent. At low frequency, especially at 0.5 THz, the centre of the Siemens star shows interference effects, which can be attributed to the finite distance from the mask. This effect can be seen in both the measurement and the simulations.
# An Ultra-Thin Composite Metasurface with Hybrid-Damping Modes for Broadband Sound Absorption
## 3 Compound HR Structure with Hybrid-Damping Modes
### Structure of the Broadband Unit and Cell
The arrows represent the peak frequencies and the reactance zeros of the compound cells. (**d**) The complex frequency plane representation of the hybrid-damping cell. which is called the critical coupling condition. It can be seen that the first zero of the hybrid-damping cell is located beneath the real axis, indicating the over-damping mode of the peak, while the second zero falls on the real axis, attributed to the matched-damping impedance, thereby facilitating perfect absorption. Furthermore, the second peak exhibits a more significant leakage rate (distance) between the zero and pole, which can contribute to a wider bandwidth. By coupling multiple over-damping peaks, the broadband absorption band can be obtained within the lower-frequency range, even achieving perfect absorption once again, which has been an effective method to reduce the structure thickness [21; 23]. However, in order to fully utilize the coupling effect, the over-damping peaks impose stringent requirements on peak frequency, making it challenging to simultaneously adjust both the first and high-order peaks to their target positions. On this basis, the absorption performance can be significantly enhanced by the adoption of hybrid-damping modes, which exhibit a superiority in low-frequency broadband absorption by integrating the benefits of over-damping and matched-damping modes.
# The Effects of Compression on the Detection of Atrial Fibrillation in ECG Signals
## 2 Methods  
### ECG Database  
The ECG database employed for these experiments is the MIT-BIH AF database (AFDB) [31; 32]. This database includes 25 long-term ECG recordings of human subjects with atrial fibrillation (mostly paroxysmal). Of these, 23 records include two ECG signal channels. The individual recordings are each 10 h in duration, sampled at 250 Hz with 12 bit resolution, with accompanying expert beat annotations. The original analog recordings were made using ambulatory ECG recorders with a typical recording bandwidth of approximately 0.1 Hz to 40 Hz. The rhythm annotation files were prepared manually and contain rhythm annotations of AF, atrial flutter, atrio-ventricular functional rhythm and all other rhythms. The RR interval series corresponds to both AF and non-AF rhythm types. Non-AF rhythm includes three rhythm types (atrial flutter, atrio-ventricular functional rhythm, and all other rhythms). This database includes recordings with 1,282,369 annotated QRS complexes of which 532,276 (42.5%) are labelled as AF with a duration of 94.99 h and 319 episodes of AF.