esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Experiments
### Experiments with V-Net
Moving deeper into the experiment conducted and analysing case-by-case performances obtained, we found that lower accuracy values occur when the pathology occupies a very small volume (under the 100 elements), and it has a highly heterogeneous context. V-Net has difficulties in identifying a very small lesion, as illustrated in Figure 10, where the segmented mask has a spatial distribution quite different from the reference mask. We conducted a third experiment by using a reduced set of data obtained by the initial in-house data set, by eliminating cases in which pathology occupies volumes under 100 voxels. The final dataset is composed of 39 T1c volumes of which 12 for test and the remaining 27 used in 3-fold cross-validation. Results obtained are shown in Table 6.  
Comparing performances obtained by the SVM configuration optimised for inter-patient analysis, shown in Table 2, we noticed that performances of the two classifiers are in this case comparable. Analysing in detail, the segmentations performed we notice that the masks produced by V-Net have a higher level of spatial consistency than those produced by SVM, making the use of MO ineffective. As an example, Figure 11 shows results produced by SVM and V-Net highlighting differences in the computed segmentation masks. As regard hyperparameters and execution time, the pre-training task takes about 150 h on an NVIDIA(tm) 1080 Ti with 11 GB of RAM, and the training with the in-house data takes about 7 h. In training we used the stochastic Adam optimizer, the shuffle in every epoch, InitialLearnRate = \(1\times 10^{-3}\), LearnRateSchedule = piecewise, LearnRateDropPeriod = 5, RateDropFactor = 0.97.
# Radiation-Hardened 16T SRAM Cell with Improved Read and Write Stability for Space Applications
## 2 Proposed RHHS16T SRAM Cell
### SEU Recovery Analysis
However, it is known that charge sharing between transistors can be avoided by maintaining a distance of at least 1.62 \(\upmu\)m and 0.6 \(\upmu\)m between PMOS transistors or between PMOS and NMOS transistors, respectively [21]. Considering this, the layout of the proposed cell, as shown in Figure 2, maintains distances of 2.655 \(\upmu\)m and 4.89 \(\upmu\)m between Q-S1 and QB-S1, respectively, to avoid multi-node upsets occurring at these node pairs. Figure 3: Simulation results of the basic operation of the proposed RHHS16T cell.
# Saturable Absorption Dynamics of Highly Stacked 2D Materials for Ultrafast Pulsed Laser Production
## 5 Graphene and Graphite SAs  
### Graphene SAs  
Since the discovery in 2004, graphene, a hexagonal carbon network with monoatomic thickness, has triggered extensive studies on its various exotic physical properties. In recent years, benefiting from ultrathin nature and high light-matter interaction, graphene has attracted considerable attention from laser photonic community. Particularly, infrared laser sources in the spectral range of 1800-2000 nm, which can be realized by fiber optical systems, are currently of topical interest due to their significance in remote sensing, spectroscopic analysis and medical therapy. This range can cover absorption lines of several important gases like carbon dioxide (CO\({}_{2}\)) or hydrogen bromide (HBr) [76], suggesting possible construction of cost-effective high-performance gas sensing platforms. It has also been shown that 2000-nm laser outperform 1000-nm and 1550-nm sources for dermatological treatment and medical surgery, allowing precise and efficient optical scalpels [77; 78].  
[PERSON] et al. used graphene as a SA to make 1884-nm pulsed laser via efficient passive mode-locking by simply inserting graphene between the ferrule connectors of a fiber cavity [79]. For large-area production, a graphene film was fabricated by a chemical vapor deposition method and carefully transferred onto the ferrule of a ring-fiber cavity incorporated with a Tm-doped gain fiber suitable for 1900-nm laser production (Figure 18). To confirm that the mode-locking originates from the graphene SA, the laser was first launched without a deposited graphene SA and mode-locking did not occur for any configuration of a polarization controller (PC). Then, the graphene SA was incorporated into the laser system in a transmission mode, not in an evanescent mode that allows for  
Figure 16: (**a**) Measured single pulses with an increasing pump power. (**b**) Measured output pulse width as a function of the pump power. Reprinted with permission from [75].  
Figure 17: (**a**) Average output power and pulse energy measurements as a function of the pump power. (**b**) Measured electrical spectrum of the output pulses. Reprinted with permission from [75].  
more feasible mode-locking. Despite this, the system has readily produced well-defined mode-locked pulses as shown in Figure 19. Characteristic dips in the high-resolution spectrum were proven to coincide with water absorption lines. The optical spectral shape without these dips exhibited well the soliton features. It was supposed that the ultrathin nature of 2D materials could contribute to optical loss control/reduction and interfacial fitness for better mode-locking of SAs in a transmission mode.
# Laser Reconstruction of Spinal Discs Experiments and Clinic
## 4 Clinical Aspects of LRD of IVD in DDD of the Spine
### LRD Puncture
Figure 11: Combination of LRD and transforminal endoscopic discectomy for a female, 51 y.o., L4L5 disc herniation, MRI T2 WI: (**A**) Preoperative—disc degeneration: Pfirrmann Grade 4; (**B**) postoperative—disc degeneration Pfirrmann Grade 2. DDD decreased and formation of the new cartilage tissue is seen. Figure 10: Combination of LRD and microscopic discectomy for a female, 44 y.o., with LSS1 disc herniation: (**A**) MRI T1 WI. Preoperative (**left picture**), 6.5 months after surgery (**center picture**), 3 years after surgery (**right picture**). Change of the signal intensity at the adjacent to the disc bone (arrows) manifests an increase in disc metabolism; (**B**) MRI T2 WI. Disc degeneration after Pfirrmann [74]: Grade 4—preoperative (**left picture**), Grade 3–6.5 months after surgery (**center picture**), Grade 2—in 3 years after surgery (**right picture**). Thus, the combination of LRD with disccetomy performed in a different way (microsurgical, endoscopic, or puncture) leads to regenerative changes in the disc. This is manifested by an increase in the intensity of the signal from the disc on MRI with a decrease in the degree of its degenerative damage. This combined surgery is an effective way to prevent the progression of DDD. Currently, most of the beneficial effects have been obtained in the study of the restoration of cartilage tissue of the spine and joints. The preliminary results of the research prove the possibility of regeneration of other tissues and organs. These include bone tissue, skin, mucous membranes of internal organs, conjunctiva of the eye, vascular intima. The combination of the effect of laser treatment and the use of biological factors, including bone marrow stem cells, is very promising. However, though the mechanisms of this process have not yet been fully clarified, there is a convincing evidence of restoration of damaged tissues with different degrees of development of the pathological process. Optimal dosimetry of laser stimulation of other body tissues has not been studied. This requires further research which should be carried out in cooperation with medical doctors of various specialties, physicists engaged in the improvement of laser technology, biochemists, and morphologists. Comprehensive experimental and clinical research in this area is within the power of serious universities and research institutions working in this direction. Regenerative laser medicine will significantly shorten the treatment time for skeletal fractures, stop the development of the degenerative process of joints and internal organs, avoid many severe surgical interventions on the spine, joints, blood vessels and other tissues that currently require prosthetics. Its promising and striking results can be laser treatment of trophic ulcers and soft tissue pressure ulcers, as well as of ulcers of the esophagus, stomach, intestines, bladder, and other organs carried out endoscopically.
## 2 Validation of Finite Element Simulation Methodology
### Establishment of Finite Element Model  
The seismic isolation test model was simulated by utilizing SAP2000 software. The finite element model was developed by employing shell and beam elements to construct the primary structural framework. The concrete material used for beams, floor slabs, and walls was C45. The steel material used for bearings and buttresses was Q345, and the reinforcing bars were HPB300. For the simulation of the isolation bearings, Rubber Isolator elements were adopted to represent the horizontal behavior, whereas Multilinear Elastic elements were utilized to model the vertical response. The bilinear hysteresis model was employed in the horizontal direction for LRB analysis. In consideration of the disparity in stiffness exhibited by actual isolation bearings under tensile and compressive conditions, the tensile stiffness of the bearings within the finite element model was designated as one-tenth of the compressive stiffness. The average mesh size of the shear walls and slabs in the SAP2000 model was 400 mm, calibrated through a sensitivity analysis. The configuration of the finite element model is illustrated in Figure 3.
# Efficient and Secured Mechanisms for Data Link in IoT WSNs: A Literature Review
## 10 Network Security Attacks and Issues of Data Link Layer Protocols
Jamming attacks can be considered a subset of DDoS (distributed denial of service) [82] attacks that disrupt the radio channel by delivering many short packets to overburden the system. A DDoS assault on a WSN modifies the routing protocol information using the Dynamic Source Routing protocol (DSR), resulting in a massive quantity of unwanted traffic and the network or website being inaccessible [60; 80]. In this way, traffic flow is highly affected due to high latency. WSN efficiency will likely be disrupted if an attacker uses a vital jamming source. Thus, it can be concluded that WSNs face numerous restrictions, such as a low computing capacity, insufficient memory and energy resources, physical capture vulnerability, and the use of unreliable wireless communication networks [83]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**References** & **Data Link Layer Protocols** & **Attack** & **Issue Category** & **Network Consequence** & **Solution** \\ \hline \multirow{4}{*}{[84]} & \multirow{4}{*}{HDLC (High-Level Data Link Protocol)} & \multirow{4}{*}{Hidden node attack DoS attack} & \multirow{4}{*}{Flow control day} & A malicious node is added, or a regular node is injected with malicious code or a request. The node can infect the whole network, or network properties can be forged, causing harm to network integrity with denial of service. & For hidden node attacks, applying RTS and CTS mechanisms can help prevent hidden node attacks. These mechanisms validate data sending and receiving for reliable flow control and data connection [85]. \\ \hline \multirow{4}{*}{[86]} & \multirow{4}{*}{Point-to-Point Protocol} & \multirow{4}{*}{Switch spoofing CAM Table} & \multirow{4}{*}{QoS} & The intruder sets up a device to impersonate a switch and sends DTP negotiation frames. Both VLANs borne on the trunk are sent to or collected by the attacker. The attacking host can then access traffic from several VLANs. & Applying port-security protocols and dynamic MAC restrictions can help secure switch spoofing and CAM table exhaustion attacks [87]. \\ \hline \multirow{4}{*}{[88]} & \multirow{4}{*}{CDP (Cisco
# Resolving Persistent Packet Collisions through Broadcast Feedback in Cellular V2X Communication +
## 1 Introduction
The solution based on the feedback from broadcast receivers has hardly been attempted thus far. As mentioned above, the receiver feedback, newly introduced in NR V2X [6], is only for unicast and groupcast traffic and not for the broadcast. One of the reasons is because broadcast receivers can be positioned at various distances and under different channel conditions relative to the colliding transmitters, which can cause the provided reports to be conflicting. However, this paper shows that the broadcast feedback is feasible in the standard framework and can be utilized to signal potential persistent collision events. The key is in defining the region of interest (ROI) and understanding the relations between received signal strength indicator (RSSI), signal-to-interference-and-noise ratio (SINR), and in-band emission (IBE) conditions in the packet collision events that occur in a given ROI. The design objectives of the proposed scheme are as follows:  
* Resolve the persistent packet collision problem in sensing-based semi-persistent scheduling for Sidelink Mode 2 in NR V2X communication, so that any consecutive collisions are short-lived and preferably within two packets;
* Resolve the persistent packet collision problem without sacrificing other performance metrics. In particular, maintain the same level of packet reception ratio (PRR) as in the unmodified SPS;
* Construct the solution as an opportunistic QoS enhancer for the standard SPS algorithm within the confines of the standard framework. It should be stressed that improving the overall PRR is not the main objective. Instead, it is given as a design constraint under which the main objective is to quickly terminate potential persistent packet collisions. Indeed, the proposed scheme reduces the length of packet collision episodes by more than an order of magnitude compared to SPS, while maintaining the PRR. In addition, the bandwidth overhead of the proposed scheme is negligible. Last but not least, it can be implemented through existing features in the standard framework.
# A Survey on Physical Layer Techniques and Challenges in Underwater Communication Systems
## 2 UWAC Physical Layer Techniques
The receiver assembly is made simpler in a frequency-selective channel using the OFDM with a cyclic prefix (CP). This makes each subcarrier only experience flat fading [38]. Moreover, redundancy across carriers employing coding achieves robust performance. The UWAC systems relying on OFDM codes were researched theoretically in several publications [39; 40; 41; 42]. However, experimental results for any of these systems are not available. [PERSON] and [PERSON] [43] used cold shallow water to design and test a low-speed OFDM communication system. [PERSON] and [PERSON] [44] studied the UWAC system with multicarrier quadrature amplitude modulation (QAM) or QPSK. The simulation model for the UWAC channel was developed as a Rician or Rayleigh fading channel, but it did not show any experimental results. [PERSON] and [PERSON] [45] performed simulations to study the influence of time and frequency selectivity on OFDM-UWC and determined that a robust system could be established. By developing multipath Doppler diversity in the channel, [PERSON] and [PERSON] [46] revealed a low-frequency long-range OFDM communication link to the Baltic Sea. [PERSON] et al. [47; 48] established a multicarrier high-speed communication link near Hong Kong's shallow coastal waters. Lately, [PERSON] et al. [49] confirmed long-range low-speed OFDM communication in the Mediterranean sea. OFDM is employed in many telecommunication schemes, particularly to deal with impulsive noise [50; 51; 52]. OFDM can be appropriate for UWA applications because warm shallow water exhibits impulsive ambient noise. Investigators of the UWACs have not developed these types of OFDM characteristics. Time reversal mirroring (TRM) has been employed in the ocean and laboratories [53; 54]. This technique utilizes the time symmetry in the wave equation to transfer energy back to the source regardless of the channel complexity by effectively utilizing the ocean as an analog computer. This provides the idea to communicate using TRM [55]. For TRM, sound propagation over the ocean must not vary significantly across the transmission cycle. Long coherence periods have been discovered in deep and shallow water in low-to-mid frequency ranges. Minor deviations in the surroundings including surface wave activity, are observed to be critical at high frequencies. As a result, TRM is impracticable for high-frequency transmission due to the extremely low coherence durations. TRM is normally applied in combination with a wide-ranging array of transducers. The TRM gain in the system, although theoretically possible to be implemented with only one transducer, is expected to be negligible. As a result, TRM is not regarded relevant in high-frequency UWAC systems with a single transducer. Spatial diversity processing, MIMO systems, and space-time coding have been the focus of recent UWAC research [56; 57; 58]. As all these methods use arrays at the receiver and/or transmitter, they are not directly related to the research completed in this paper.
## 2 Reservoir Rock Characteristics and Engineering Problems
### Rock Cracks and Solution Cavities Characteristics  
The rock samples were collected from the Dengying Formation at depths ranging from 4959 m to 5481 m of Well GS10 in the Gaoshiti-Moxi area of the Sichuan Basin using the core drill bit, as shown in Figure 2. These rock samples were obtained when the drilling operation reached the gas-producing reservoir. The dissolution pores in the rock of the Dengying Formation exhibit a variety of shapes, predominantly irregular or nearly circular. The distribution of these pores is notably uneven, often displaying band-like, honeycomb, patchy, and scattered arrangements. The formation is rich in solution cavities, with an average density of 26.45 per meter. Horizontal cracks are more common, followed by inclined ones. A large number of small cracks are also presented, with quantity densities ranging from 0.86 to 8.26 per meter. Notably, in the solution cavities and cracks, we observe fillings of quartz, dolomite, and asphalt. Additionally, some cracks are observed to be associated with solution cavities, indicating a complex interplay of geological processes.
###### Abstract  
Inertial sensors are widely used for classifying the motions of daily activities. Although hierarchical classification algorithms were commonly used for defined motions, deep-learning models have been used recently to classify a greater diversity of motions. In addition, ongoing studies are actively investigating algorithm efficiency (e.g., training time and accuracy). Thus, a deep-learning model was constructed in this study for the classification of a given motion based on the raw data of inertial sensors. Furthermore, the number of epochs (150, 300, 500, 750, and 900) and hidden units (100, 150, and 200) were varied in the model to determine its efficiency based on training time and accuracy, and the optimum accuracy and training time was determined. Using a basic long short-term memory (LSTM), which is a neural network known to be suitable for sequential data, the data classification training was conducted on a common desktop PC with typical specifications. The results show that the accuracy was the highest (99.82%) with 150 hidden units and 300 epochs, while the training time was also relatively short (78.15 min). In addition, the model accuracy did not always increase even when the model complexity was increased (by increasing the number of epochs and hidden units) and the training time increased as a consequence. Hence, through suitable combinations of the two factors that constitute deep-learning models according to the data, the potential development and use of efficient models have been verified. From the perspective of training optimization, this study is significant in having determined the importance of the conditions for hidden units and epochs that are suitable for the given data and the adverse effects of overtraining.  
inertial sensor; long short-term memory; motion classification; efficiency +
Footnote †: journal: Applied Sciences
# Eye Fatigue Detection through Machine Learning Based on Single Channel Electrooculography
## 4 Method  
### Signal Pre-Processing  
Initially extracted EOG signal was interspersed with significant industrial frequency interference and unavoidable baseline drift which needs to be pre-processed [14]. The frequency of the EOG signal is in the range of 0.2-30 Hz. The main interference sources are baseline drift and power frequency noise. To eliminate power line interference and baseline drift, a notch wave of 50 Hz and a fourth-order band-pass filter of 0.2-30 Hz is devised in this article.  
From Figure 7, it is apparent that the EOG signal becomes smooth and clear after it has been filtered by the two filters. The quality of the EOG signal has been improved significantly therefore it has a high signal-to-noise ratio.
# Predictive Validity of the Single Leg Hamstring Bridge Test in Military Settings
## 2 Materials and Methods
### Data Analysis  
Categorical variables are displayed as numbers and percentages, and numeric variables are presented as means and standard deviations. All numeric variables were firstly checked for normality of distribution with the Shapiro-Wilk test. If not stated otherwise, all calculations were performed using SPSS statistical package version 25 (SPSS Inc, Chicago, IL, USA).  
The agreement between measurements was assessed with the intraclass correlation coefficient (ICC\({}_{2,1}\)) and with the 95% confidence interval (95% CI) for ICC. Calculations were performed using SPSS based on a mean rating (k = 2), absolute agreement, 2-way mixed-effects model. ICC values were interpreted according to recent guidelines [24]. Absolute and relative measurement error was assessed with a standard error of measurement (SEM) and with the SEM %, respectively, with the additional calculation of smallest real difference (SRD) and Bland-Altman analysis [25]. The coefficient of variation (CV) was calculated as a ratio between the standard deviation and the mean.  
The APFT mark (1-5) was used as the outcome variable in the ROC analysis, where marks 4 and 5 were joined to form a new mark (good to excellent baseline fitness), as opposed to marks 1-3 (poor to moderate baseline fitness). The ROC analysis was then carried out to examine the discriminatory ability of the SLHBT to predict APFT passing score >4 as an objective measure of good baseline fitness quantified by the area under the curve (AUC) as the diagnostic power of a test. Optimal sensitivity and specificity were the values yielding maximum AUC from the ROC curves. The optimal value was considered the cut-off point with the fewest false positives and negatives [26]. MedCalc 16.8.4 statistical software (Ostend, Belgium) was used for ROC analyses.  
Following the cut-off point calculation for the SLBHT, we introduced a new categorical variable based on that cut-off point and performed an analysis of covariance (ANCOVA) where SLBHT performance was an independent predictor of overall physical performance (based on performance on all tests) and body mass was used as a covariate. A partial eta square was calculated to evaluate the effect size. The significance level was set at _p_-value <0.05.