esa-sceva/satcom-chunk-collection huggingface dataset:
# On Ad Hoc Communication in Industrial Environments
## 5 Examination of the Industrial Ad Hoc Channels
### Effects of Multi-Hop Relaying  
Mobile Ad hoc NETworks (MANETs) [2], Delay Tolerant Networks (DTNs) [3] and Wireless Sensor Networks (WSNs) [27] are emerging and developing trends in the industrial context. An ad hoc network's major advantage over infrastructure networks (e.g., WiFi) is flexibility and redundancy. They are envisioned to mitigate the dependence on network infrastructure and enhance a combined wireless network structure.  
In this work the NEP is used to examine the advantage of redundant multi-hop links between mobile nodes in industrial environments. The previously examined route lifetime is the primary metric for evaluating the improvement. It is envisioned that the utilization of redundant links increases the route lifetime. Another expected improvement will be that multi-hop relaying enhances the network connectedness. In this examination only the mobile industrial measurements are used. Different network sizes, in terms of number of hops, are examined.  
The relevant metrics regarding both expectations were examined and are presented in Figure 5. It can be confirmed that the utilization of multi-hop connections is beneficial in the mobile industrial context. Firstly, the network connectedness increases; therefore, more nodes can be reached by any other node. Secondly, the average route lifetime is positively affected. The number of available hops is highly relevant when examining these benefits. For the examinations it must be assumed that finding and establishing a route of length \(h\) (in hops) is possible within \(dt\). As illustrated in Figure 5, the first hop is the most effective in increasing network connectedness and route lifetime. It is suspected that in AGV scenarios with more mobile nodes and/or on a bigger area, more hops would be effective in increasing the network connectedness. In the observed scenarios the first and second hops were most effective in enhancing the route lifetime, while only the first hop enhanced the number of reachable nodes.  
Figure 4: Complementary Cumulative Distribution Function (CCDF) of route lifetime in different scenarios.
## 5 Conclusions  
We presented a free vibration analysis of MHCAP consisting of CNT/CF/matrix resting on a two-parameter substrate subjected to temperature gradients. The model was based on HSDT, and the Halpin-Tsai model was combined with a micromechanical scheme to extract the effective mechanical properties of MHCAP. The governing equations were obtained through [PERSON]'s principle and solved with the GDQM. After verification, we carried out an intensive parameter study which revealed the following conclusions:  
* Annular plates with lower thickness to outer radius ratio presented better vibration performance.
* Reinforcing MHCAP with FG-A as the distribution pattern of CNTs exhibited the best vibration response in comparison with any other patterns tested.
* In the case of Pasternak-type elastic substrate, the lowest natural frequency was associated with b/a = 2.3 as the outer radius to inner radius ratio of the MHCAP.
* The effect of the Winkler coefficient on the vibration performance of the plate was more significant when the outer radius to inner radius ratio was higher.
* Applying a sinusoidal temperature rise results to a highest natural compared with associated results of other patterns of temperature rise.
* When the outer radius to inner radius ratio of the MHCAP was larger, the minimum frequency occurred at higher, corresponding temperature of the top surface.
* Unlike compression load, applying higher load in extensional direction led to higher natural frequencies.  
Increasing the volume fraction of carbon fiber V\({}_{\text{F}}\) improved the vibration characteristics of the plate when \(0\leq\theta\leq 0.425\pi\), whereas increasing V\({}_{\text{F}}\) had a negative effect on the vibration response of the MHCAP in the case of \(0.425\pi\leq\theta\leq 0.5\pi\).  
Higher power index in the relations of STR and PTR led to a better vibration study.  
The sensitivity of vibration response was higher in the case of higher nonlinear temperature gradients.  
Figure 13: Sensitivity of the natural frequency of MHCAP with clamp-clamp boundary conditions to nonlinear temperature gradient for different values of \(\beta\) parameter in STR and power form temperature rise (PTR) and h/b = 0.1, \(\theta\) = \(\pi\)/4, \(W_{\text{CNT}}\) = 0.02, \(V_{\text{F}}\) = 0.2, FG-A, \(K_{\text{p}}\) = 10 [MN/m], and \(K_{\text{w}}\) = 100 [MN/m\({}^{3}\)].  
**Author Contributions:** Conceptualization A.R., M.S. and T.R., Formal analysis A.R. and M.S., Writing--original A.R., M.S. and T.R., Writing--review A.R., M.S. and O.N.A., Visualization A.R. and M.S. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Conflicts of Interest:** The authors declare no conflict of interest.
## 3 Methodology
### Time-Embedding Module  
This section describes the construction of the temporal-embedding module. To solve the problem of temporal disorder in the user trajectories, we convert the user's time trajectory data into fixed-length time trajectory vectors (TTVs). We utilize these vectors to predict whether a user made a POI check-in at a specific time interval. First, we determine the time of the user's first check-in point and then compute the check-in time for each subsequent point. These time points are then mapped to the corresponding locations in the time trace vector. The position associated with a check-in timestamp is assigned a value of 1, indicating that a check-in timestamp exists for that period. Conversely, the remaining locations are assigned a value of 0, indicating that there is no timestamp for that period. Presumably, if a location in the time track vector is 0, then the user will not access the POI in the period after that.  
To further improve the accuracy of the time embedding, we add two dimensions after the 48-dimensional time track vector to indicate whether the track occurs mainly on weekdays or weekends. First, we iterate through all check-in events and count the number of check-ins on weekdays and weekends separately. If the number of weekday check-ins is more than half of the total number of check-ins in the trajectory, the first extra dimension (weekday dimension) should be set to 1; otherwise, it should be set to 0. Similarly, if the number of weekend check-ins is more than half of the total number of check-ins in the trajectory, the second extra dimension (weekend dimension) should be set to 1; otherwise, it should be set to 0. Figure 3 illustrates an example of temporal-data mapping. With this approach, we construct a 50-dimensional final trajectory vector that contains information about the temporal distribution and global information about whether the trajectory mainly occurs on weekdays or weekends.  
In order to capture the general patterns of the TTVs, we trained an embedding layer to map each TTV to a low-dimensional vector. The embedding for each TTV is learned from its historical check-in sequences. The embedding of the time trajectory vector (\(t\)), denoted as \(e_{t}\), serves as the input data and is defined by Equation (1), as follows:  
\[e_{t}=f^{embed}(t)\in R^{\tau} \tag{1}\]  
where \(\tau\) is the time trajectory vector-embedding dimension.
## 3 Experimentation
### Experimental Setup  
The experimental setup was divided into three units, the layout is shown in Figure 4. The first unit was the vibrating mechanism which consists of a signal generator, power amplifier, and mechanical shaker. The signal generator generated the input sine wave functions to provide vibration load.The function of the power amplifier was to amplify this input sine wave and then input it to the shaker. The shaker provided the vibration to the specimen at its natural frequency with the fixed amplitude of 2 mm against amplified voltage 3.2 V. The second unit was the thermal unit comprising a thermal couple, PID temperature controller, and thermal mat. The K-type thermal couple is used to measure the specimen surface temperature. The function of the PID temperature controller is to control the heat supply to the specimen through the heating device thermal mat. A uniform temperature along the beam was achieved by placing the thermal mat at both ends as shown Figure 5. The third unit is the data acquisition which consists of strain gage, accelerometer, data acquisition card, and National Instruments SignalExpress. The strain gage is attached near the fixed end, while the accelerometer is mounted at the free end of the specimen to measure the modal amplitude. National Instrument DAQ card (i.e., NI 9234 and NI 9235) and SignalExpress are used to analyse the dynamic response of the system. The details of the experimental setup are shown in Figure 5.  
Figure 3: Experimental scheme.  
Figure 2: (a) Experiment specimens; (b) no crack specimen geometry.  
Figure 4: Experimental layout.
# Migrating from Developing Asynchronous Multi-Threading Programs to Reactive Programs in Java
## 3 Related Work
### Evaluating Hibernate Reactive for Scalable Database Solutions  
[PERSON], in the study conducted by the Hibernate Team, evaluates the use of Hibernate Reactive for asynchronous, non-blocking database access in Java applications. Hibernate Reactive builds on reactive programming principles to enhance scalability, allowing for higher levels of concurrency with reduced latency and optimized resource usage. In performance benchmarks, Hibernate Reactive maintained response times under 10 ms at loads of 35,000 requests per second, whereas its synchronous counterpart, Hibernate ORM, only achieved similar performance up to around 20,000 requests per second. These findings highlight Hibernate Reactive's advantages in handling high-load scenarios, with fewer threads required to achieve these results [19].  
Additionally, the study points out specific cases where Hibernate Reactive proves beneficial, particularly in applications where scalability and resource efficiency are priorities. However, certain limitations are noted, such as potential overhead in complex transactions and multi-join operations, which could impact performance. For example, encapsulating units of work within explicit ACID transactional boundaries can tie up physical connections, limiting the benefits of reactive multiplexing. This is particularly evident in data-intensive environments where relational complexity introduces latency that offsets the reactive gains. Similarly, multi-join queries, which are common in analytics or relationally complex systems, can impose significant performance costs, making Hibernate Reactive less efficient in such scenarios [19].  
As a result, the study suggests that while Hibernate Reactive offers significant value within a reactive architecture, a careful assessment of its applicability is essential, especially in environments with complex data requirements. In particular, applications that prioritize high-throughput, non-blocking operations stand to gain the most from Hibernate Reactive, whereas systems with heavy transactional demands or complex relational models may find traditional synchronous approaches more suitable. This highlights the need for a case-by-case evaluation to determine the feasibility of adopting Hibernate Reactive [19].
# Learning Robust Shape-Indexed Features for Facial Landmark Detection
## 5 Conclusions  
This paper proposes a sparse-to-dense network (STDN) to deal with occlusion problems. The proposed framework employs a patch resampling approach to improve the quality of shape-indexed patches, which is helpful for extracting robust shape-indexed features. Moreover, the STDN exploits the group relations between facial components to handle occluded faces using a carefully designed group-relational module. Extensive experiments were conducted to evaluate the performance of the STDN in normal conditions and occlusion. The experimental results show that STDN improves by 9.16% on Fullset compared to the baseline, achieves 5.33% on the Challengingset, and improves by 15.53% compared to the baseline, which fully demonstrates that STDN outperforms most current methods in terms of robustness against occlusion. Currently, STDN only considers the nose as an anchor to constrain other facial groups, future work can learn occlusion-adaptive group relations to make full use of the spatial relations of faces, and also consider learning differential loss function, which aims at adaptively focusing on the occluded region.  
[PERSON] made contributions to conception and manuscript writing; [PERSON] examined and supervised this research and outcomes; [PERSON] revised and polished the manuscript. All authors have read and agreed to the published version of the manuscript. This research received no external funding.  
No. applicable.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Method** & **Challenging** & **Common** & **Full** \\ \hline STDN with GRM* & 5.57 & 3.09 & 3.57 \\ STDN with GRM** & 5.53 & 3.06 & 3.54 \\ STDN with GRM*** & 5.48 & 3.04 & 3.51 \\ STDN with GRM & 5.33 & 3.02 & 3.44 \\ \hline \hline \end{tabular}
\end{table}
Table 7: Ablation experiments of different group division strategies on 300 W. *, **, *** indicate the results using the different group division strategies as shown in Figure 10.  
Figure 10: Strategies for dividing face shape into different facial groups.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \(\epsilon\) & 0 & 0.1 & 0.2 & 0.3 & 0.4 & 0.5 & 0.6 & 0.7 & 0.8 & 0.9 & 1.0 \\ NME & 7.28 & 5.41 & 5.40 & 5.41 & 5.38 & **5.33** & 5.41 & 5.45 & 5.46 & 5.59 & 5.54 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Ablation experiments of hyperparameter \(\epsilon\) on 300 W Challengingset.
# Objective Assessment of Porcine Voice Acoustics for Laryngeal Surgical Modeling
## 4 Discussion
### F0-Based Parameters  
Parameters developed for human voice and based on fundamental frequency (F0) did not show consistent trends for the different pigs between pre- and post-surgery. This is not surprising, as these parameters all depend on a correctly detected F0. Jitter measures the perturbation in cycle lengths, which are calculated based on detected F0 [21]. Shimmer measures amplitude perturbation between consecutive cycles, which also relies on correctly detected cycles, i.e., F0 [21]. CPP measures the prominence of the fundamental quefrency peak in the cepstrum. The fundamental quefrency and thereby the position of this peak are directly related to F0 [25].  
Praat and other voice analysis tools may be able to detect an F0 for almost any type of signal if the settings are chosen liberal enough. However, if the signal itself has a certain degree of aperiodicity, as is the case with most pig phonation, this will only result in a mostly random F0 and therefore no meaningful F0-based parameters. Small pig-specific changes as observed here, e.g., Pig 2 Jit decreasing slightly or Pig 3 Jit increasing slightly, are most likely related to subtle patterns within the signals that may influence the F0 detection algorithm but much less to the parameter itself. We therefore strongly advise against the use of F0-based parameters on aperiodic pig voice.
## 1 Introduction
Interfaces between dissimilar materials often control phonon and electron transport, especially at the nanoscale level where the importance of the interfaces relative to bulk material properties is substantially increased [42; 44; 45]. CNTs, like most nanomaterials, require a metal support that can efficiently harvest electrons and thus take advantage of their physical properties [21; 46]. Notably, short covalently bonded organic molecules at the interface can dramatically increase adhesion between CNT arrays and noble metal contacts, resulting in an approximately sixfold reduction in the thermal interface resistance [14]. Because of their geometrical shape, the conducting properties of CNTs depend on their orientations in assemblies, with true physical properties being lost at the interfaces between the anisotropic nanotubes and metal substrates [47; 48; 49]. The electrical conductance of a CNT is closely related to its orientation and interface contact [50]. Based on extensive work with highly ordered pyrolytic graphite, the basal and edge plane reactivities [51] and the electrochemical behavior of CNTs have been shown to differ [52; 53]. Various reports have indicated that the edge planes of CNTs have higher electron transfer rates than the basal planes [51; 53; 54]. Furthermore, the intrinsic metallic or semiconducting properties of CNTs, as well as their single- or multi-walled nature, can lead to discrepancies in the measured electron transfer rates. Theoretical studies on simulating the interface between individual CNTs and metals have found great resistance at the metal-CNT interfaces with simple contact [55; 56; 57]. More recently, systematic methods to control, engineer, and study open-ended CNTs have been developed, and the applications of CNT tip reactions have led to the development of highly sensitive sensors [35; 58]. This paper reports a method for chemically joining open-ended CNTs to metal substrates (Cu or Pt). For this purpose, high-density CNTs (HD-CNTs) with functionalized open ends were positioned orthogonally to a metal substrate. The metal substrate was also functionalized with suitable organic linkers to promote a chemical junction between the carboxylic and amine groups at the ends of the CNTs and metal substrates, respectively. Successful cross-linking between the CNTs and the linkers on the metal surface was demonstrated via conductivity measurements and electrochemical characterization.
# Spatial and Momentum Mapping Modes for Velocity Map Imaging Spectrometer
## 4 Experiment  
We test the VMI spectrometer with above-threshold ionization (ATI) of argon (Ar). The supersonic Ar gas beam is ionized with a linearly polarized, 35 fs, 800 nm, 1 kHz Ti:Sapphire laser. The laser is focused to a peak intensity of 1.4 \(\times\) 10\({}^{14}\) W/cm\({}^{2}\) through an optical lens with a focal length of 400 mm.  
The supersonic jet, the reaction center of the VMI lens, and the laser focus may be misaligned from each other. This misalignment needs to be corrected at the beginning of the experiment. First, we put the laser focus on the reaction center of the VMI lens. The position of the laser focus and that of the reaction center of VMI lens are determined by checking the parent ion images of the residual gas in the uniform field mode and the focusing mode, respectively. Here, the residual gas molecules are preferred because they move isotropically. If the laser focus is misaligned from the reaction center, the center of the ion image will shift by switching the VMI lens between the uniform field mode and the focusing mode. Because the supersonic molecular beam possesses a specific mean velocity, it is not a suitable target for this alignment. By moving either the optical lens or the whole spectrometer, the distance between the laser focus and the reaction center can be reduced to below 0.5 mm, and then we believe the alignment quality is acceptable. Finally, by monitoring the ion counts, we switch on the supersonic molecular beam and move it to reach the maximum overlap with the laser focus. In the end, the laser and supersonic molecular beam intersect at the reaction center of the VMI spectrometer.  
In order to further improve the resolution during the experiment, we set the exposure time of a single image to 50 ms, which can avoid the severe overlapping of fluorescence spots on the P46 screen. We enhance the contrast of each image using morphology [27]. Each energy spectrum generally needs to accumulate 20,000 images.
# Effective 5G Wireless Downlink Scheduling and Resource Allocation in Cyber-Physical Systems +
## 2 Related Work  
In a mobile network, when a user requests data from the Internet, the request is sent to the base station. The base station retrieves the data through the Internet and provides them to the user in the form of data packets. These data packets are framed into larger data frames and transmitted from the base station towards the User Equipment (UE). These data frames consist of time and frequency resources in terms of RBs and the number of subcarriers, respectively. Allocating resources to multiple users in a single data frame is known as the SRA problem at the base station. SRA has been studied over the decades from a variety of performance perspectives: (1) spectral efficiency, (2) scalability, (3) computational complexity, (4) Quality of Service (QoS), (5) fairness, (6) target delay, (7) queue length, (8) priority, (9) Guaranteed Bit-Rate (GBR), etc. [18; 19; 20; 21]. In this paper, we classify state-of-the-art approaches for SRA into two broad categories: (1) channel-dependent and (2) channel-independent SRA algorithms, as summarized in Table 1. Within each category, they are further classified into subcategories.  
All the algorithms in Table 1 are used to handle either a single type of traffic or multiple QoS classes at the base station. In the case of 5G, SRA decisions take place based on the queue and Channel State Information (CSI); hence, the channel-independent SRA algorithms are not relevant. In the case of channel-dependent algorithms, most work has been focused on supporting a GBR and dealing with delay-sensitive traffic. However, in the case of 5G, the base station needs a cross-layer SRA algorithm, which can make cross-layer SRA decisions considering the queue and CSI. Table 1 shows the state-of-the-art system-centric cross-layer SRA algorithms that make SRA decisions considering both the queue and channel state. However, none of them has specifically been designed from the 5G perspective. In 5G, the base station needs to serve diverse traffic of different use-cases in each transmission interval. An advanced cross-layer approach [13] considers the queue state and CSI together for SRA decisions; however, it is a greedy algorithm that may produce suboptimal results. To address this problem, we have proposed a new cross-layer SRA algorithm based on dynamic programming in [17] that makes optimal SRA decisions at 5G base stations with polynomial time complexity. In this paper, we extend our previous SRA framework [17] to accommodate various 5G use-cases.
## 5 Specific Application of Topic Identification Models and Algorithms
### Application of LDA Theme Model and Its Derivative Models  
As shown in Figure 3, LDA and its derivative models are the most widely used in the research sample. Their specific applications are described and summarized in the following section.