esa-sceva/satcom-chunk-collection huggingface dataset:
# Comprehensive Investigations on Fluid Flow and Cavitation Characteristics in Rotating Disk System
## 4 Experimental Analysis
### Experiment Results  
The motor's speed was gradually increased from 300 rpm to 1200 rpm using a frequency converter, and finally 350 rpm, 550 rpm, and 1050 rpm were chosen to correspond to low, medium, and high speeds, respectively, based on the captured images. It should be noted that the previous paper argued that cavitation is related to angular velocity, the theoretical analysis part used a smaller size model to simplify the calculation, and the inner and outer diameters of the friction disk in the experiment are much larger than those in the theoretical part.  
To demonstrate that rough elements can cause cavitation, a non-texture friction disk was first installed as a control experiment on a transparent experimental bench. Figure 32a-c shows the surface cavitation pattern of the non-texture friction disk under different speed conditions, and no cavitation bubbles are generated in the field of view under all three speed conditions, demonstrating the same pattern as Figures 11 and 17. It is once again demonstrated that cavitation does not occur on smooth or near-smooth surfaces.  
Following that, the non-texture friction disk was replaced with a 6% texture friction disk, and as shown in Figure 32d, there were no cavitation bubbles at 350 rpm, indicating that there was no cavitation at low speed. As shown in Figure 32e, cavitation bubbles appeared first at the outer diameter at 550 rpm. As shown in Figure 32f, multiple narrow cavitation bubbles appeared in the view field at 1050 rpm, indicating.  
The results of modeling calculations, CFX simulations, and experiments are consistent in several ways: cavitation does not occur on smooth surfaces, cavitation preferentially occurs on the area around the outer diameter (larger angular velocity), and increasing rotational speed enlarges the cavitation region. However, the texture structure in this experiment is not a regular hexahedron, the experiments cannot capture the cavitation generation process microscopically, and the modeled fluid is an ideal medium free of impurities; all of these limitations result in non-conformity between the experiments and the modeling, and this will be the focus of future research.  
Figure 31: Transparent test platform (1 = high-speed camera; 2 = lens; 3 = computer; 4 = fill light; 5 = host; 6 = motor; 7 = data collection unit; 8 = magnet powder brake; 9 = torque sensor; 10 = coupling; 11 = base).
## 4 Results and Discussion
### Freeze-Thaw Resistance  
One of the most critical durability properties of concrete is its resistance against degradation due to freeze-thaw cycles, especially in cold climates [53]. The compressive strength results of specimens exposed to freeze-thaw cycles and cured in tap water are compared in Figure 11. As shown there, for all mortar mixes, the compressive strength of specimens under freeze-thaw conditions was less than that of normal conditions. In addition, by increasing the cement replacement ratio by more than 5%, the durability against freeze-thaw cycles decreased. Many researchers have investigated the freeze-thaw resistance of concrete with different SCMs, and conflicting results have been reported considering the age test, number of cycles, cycle temperatures, and duration of cycles. For example, in the case of using GGBFS, while in some works, concrete samples made with pure cement showed superior performance [54], and in other research [55; 56], samples made with GGBFS displayed higher resistance against freeze-thaw cycles.  
Figure 11: Compressive strength of specimens at 28 days (tap water and freeze–thaw cycles).  
Figure 10: Relationship between the splitting tensile strength and compressive strength of all specimens.  
When concrete is affected by freeze-thaw cycles, ice formation in capillary pores generates expansion stress, which can be released if entrained air is present [57; 58; 59; 60; 61; 62]. So, improving the freeze-thaw resistance, reducing capillary pore volume, and inducing proper formation of entrained air are vital for concrete production [63]. It is worth noting that the structure of voids can govern ice formation and damage occurrence in the interlock between particles [64; 65], and decrement in the capillary pore volume plays a significant role in increasing resistance to freezing and thawing [66; 67; 68]. As shown in Section 4.7, the control mix and the one with 5% cement replacement have less capillary pore volume than specimens containing 50% waste as cement replacement. As a result, specimens made with 50% waste powders have lower freeze-thaw resistance. Figure 12 shows the results of the water absorption test conducted on 50 mm cubic specimens at the age of 28 days, based on the ASTM C642 standard [47]. According to Figure 10, the 30 minutes' water absorption for the specimens experiencing 30 freezing-thawing cycles was slightly higher than that of the specimens cured in tap water. The water absorption after 24 h of specimens with different ratios of cement replacement exposed to freeze-thaw cycles was higher than that of the specimens cured in tap water. Overall, by increasing the cement replacement ratio, the water absorption of specimens after 30 min and after 24 h increased.
# Exogenous Versus Endogenous Nandrolone in Doping Investigations: A Systematic Literature Review
## 3 Results
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt}} \hline \hline
**Authors** & **Factors Influencing Endogenous Production** \\ \hline [PERSON] et al. (2002) [19] & Exhaustive exercise did not significantly increase endogenous hardolone secretion in trained male athletes. \\ \hline [PERSON] et al. (2002) [5] & Pregnancy \\ \hline [PERSON] et al. (2004) [24] & Submaximal standardized exercise does not influence endogenous hardolone production. \\ \hline [PERSON] et al. (2004) [25] & C13-labeled nandrolone \\ \hline [PERSON] et al. (2005) [26] & Nandrolone decanoate \\ \hline [PERSON] et al. (2005) [27] & In situ demethylation of endogenous steroids in stored urine samples \\ \hline [PERSON] et al. (2005) [29] & Over-the-counter food supplements \\ \hline [PERSON] et al. (2006) [30] & NA was excreted in female volunteers not treated with nandrolone, norandrostenedio, or norandrostenedioI. Additionally, the NA urinary excretion pattern during the menstrual cycle followed the essential hormonal changes, especially just before and during ovulation. \\ \hline [PERSON] et al. (2006) [31] & Unlabeled supplements containing creatinine \\ \hline [PERSON] et al. (2007) [33] & Ophthalmic solution containing nandrolone \\ \hline [PERSON] et al. (2009) [39] & Ofal of uncastrated pigs \\ \hline [PERSON] et al. (2009) [41] & Norethisterone \\ \hline [PERSON] et al. (2009) [43] & Keratyl eye drops \\ \hline [PERSON] et al. (2009) [44] & 19-nor-4-androstenedione administration \\ \hline  & Nandrolone excretion did not increase after exercise in women with a normal flow cycle. No significant difference was found in nandrolone concentration between eumenorhreic women and those taking oral contraceptives, nor was an increase in nandrolone metabolites seen following exercise. \\ \hline [PERSON] et al. (2016) [50] & Antifungal drugs, benzodiazepines, and nonsteroidal anti-inflammatory drugs not on the WADA’s Prohibited List \\ \hline [PERSON] et al. (2018) [54] & Pregnancy \\ \hline [PERSON] et al. (2018) [55] & Wild boar entrails \\ \hline [PERSON] et al. (2020) [59] & Wild boar meat \\ \hline [PERSON]. [PERSON] et al. (2023) [65] & Wild boar meat \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._  
Figure 2: Distribution of publication years. Out of a total of 57 articles, only 24 were concerned with factors influencing endogenous nandrolone production. The factors investigated in these studies are shown in Figure 3. These are as follows: wild boar meat or pork offal (5); supplements (3); mixed (post-menopausal women and male athletes) (1); physical exercise (1); exogenous nandrolone (2); stored urine samples (1); ophthalmic solutions (2); women, pregnancy, and contraceptive pills (6); antifungal, BDZs (benzodiazepepines), and NSAIDs (nonsteroidal anti-inflammatory drugs) not featured on the WADA's Prohibited List (1); and foodborne doping, including foods, drinks, and supplements (2).
## 2 Materials and Methods
### Remote Sensing Calculations and Field Measurements
#### 2.3.1 Multi-Temporal Image Analysis
Through the analysis of EVI data, the formula for Enhanced Vegetation Index (EVI) analysis is provided by the following:  
\[\text{EVI}=2.5\times\frac{\text{NIR}-\text{RED}}{\text{NIR}+\text{RED}+1} \tag{4}\]  
where NIR represents the near-infrared band reflectance, and Red represents the red band reflectance.
# Drone SAR Imaging for Monitoring an Active Landslide Adjacent to the M25 at Flint Hall Farm
## 3 Materials and Methods  
### Corner Reflectors  
Two custom-built corner reflectors were installed at Flint Hall Farm in September 2021 to provide strong and stable radar reflectors at the predominantly rural location for satellite InSAR monitoring of the landslide deformation. The two reflectors were installed for observation by the Sentinel-1 ascending and descending azimuths of 345\({}^{\circ}\) and 195\({}^{\circ}\), respectively. Subsequently, the corner reflectors were utilised as a target in the drone radar system flights, as demonstrated by similar other studies [14; 15; 22].  
The reflectors are manufactured from 2 mm thick aluminium, as this is a lightweight and corrosion-resistant material. The 0.75 m inner leg provides a theoretical Radar Cross Section (RCS) of 26 dBm\({}^{2}\); this is the minimum RCS required for detecting deformation at C-band radar frequencies [31]. The mesh perforated metal sheet facilitates the drainage of precipitation, reduces wind loads, and prevents deformities accumulation, which may otherwise impact the triple-bounce mechanism or the installation orientation and elevation angles. The 4.7 mm hole diameter produces minimal RCS losses and satisfies the requirement for diameters to be less than one-sixth of the radar wavelength [31].  
The reflectors were installed towards the centre of the Midslope Zone, Zone 1 in Figure 3 (51.25858\({}^{\circ}\)N, 0.04732\({}^{\circ}\)W); this zone is not attributed to a landslide mechanism; however, the geotechnical risk is greatest here at medium to high (Table 1). The foundation consists of a borehole casing filled with concrete, in which a scaffold pole was inserted. The installation is fenced-off to prevent damage from livestock interference (Figure 8).  
Figure 8: Corner reflectors at Flint Hall Farm, with annotated M25.
## 2 Materials and Methods
### Procedures and Devices  
All procedures were performed within the same endoscopy suite. Conventional Olympus duodenoscopes (models TJF 160 and 180; Tokyo, Japan) were used for all procedures. Fluoroscopy was performed with a standard C-arm device (General Electrics, Frankfurt am Main, Germany). All procedures were attended by a radiology technician, and the total radiation exposure was registered for all patients (mGy/min) but was not included in the follow-up protocol.  
Devices used for the ERCP procedures included the following: (1) triple lumen sphincterotomes V-System(tm) CleverCut3V (Olympus Europa, Hamburg, Germany); (2) standard guidewires VisiGlide 0.025/0.035-inch, 450 cm (Olympus Europa); (3) standard needle knife papillomavirus KD-11Q-1 (Olympus Europe); (4) triple lumen extraction balloon catheters Tri-Ex(r) (Cook Medical Europe, Limerick, Ireland); (5) controlled radial expansion dilation balloon catheters (Endo-Flex, Voerde, Germany); (6) plastic stents of different lengths and calibers (Quick Place V; Olympus Europa); (7) metallic fully and partially covered self-expandable stents of different lengths and calibers (WallFlex(tm); Boston Scientific, Marlborough, MA, USA); (8) pancreatic stents of different lengths and calibers (Advanix(tm); Boston Scientific); (9) over-the-guidewire cytology brushes (Cook Medical Europe); and (10) alligator and rat-tooth extraction catheters (Boston Scientific). All procedures have used isopamidol-based contrast solutions diluted with saline. All procedures involved mixed electrosurgical current generated by an Erbe ICC 200 device in EndoCut(tm) mode (Photon Surgical Systems Ltd., Gloucestershire, UK).  
All of the ERCP procedures were carried out by a board-qualified ERCP endoscopist. A group of four endoscopists managed all included cases. Trainees were involved in patient preparation and follow-up. In patients where biliary clearance was not achieved, or with Bismuth type 2 to 4, with primary sclerosing cholangitis, or in immunocompromised cases, antibiotic prophylaxis was administered after local protocols and local antibiotic resistance, as recommended by current guidelines [8; 9]. All patients received intracerebral diclofenac or indomethacin for the prevention of PEP as required by local protocol.  
Indications for ERCP for the studied cohort included various causes of bile duct obstruction: gallstone disease, benign and malignant strictures and extrinsic compression of bile ducts, bile duct leaks and post-operative injury, and hydatid disease. Insertion of biliary stents was performed for stricture management in patients with bile duct leaks and in cases of remnant bile duct stones and clearance failure.
# A Learned Reduced-Rank Sharpening Method for Multiresolution Satellite Imagery
## 3 Results
### Ablation Study
#### 3.2.3 PReLU  
Using the simpler Leaky ReLU activation [68] in the U-Net instead of PReLU [52] results in less stable training and worse results. Leaky ReLU is identical to PReLU, apart  
Figure 8: Loss plot convergence comparison between the proposed method with **F** initialized using PCA (gray) and **F** initialized using Kaiming uniform initialization [52] (teal). An average of ten runs of each of the four different datasets is shown, with shadings showing max and min values.  
Figure 7: Heatmap of mean SRE values for all bands of the synthetic S2 datasets for a given pair of \(\lambda\) and \(r\) values. The best SRE is 33.32 dB for \(\lambda=0.003\), \(r=9\), and within a \(5\times 5\) window centered on the top value; the worst SRE is 32.80 dB, just over a 0.5 dB difference.  
from having a single fixed \(a\) value for all bands. PReLU allows the network to adjust the size of the parameter \(a\) for each band, layer, feature, and subspace layer independently during learning. Conversely, Leaky ReLU fixes it to the chosen value for each instance. The choice for the initial value of \(a\) is relatively high, but setting it lower was found to increase the risk of exploding gradients for this network. Training the network with all PReLU layers replaced by LeakyReLU layers fixed at the initial value, \(a=0.75\), gives worse results, as the \"Leaky ReLU\" bar in Figure 6 shows.
# Determination of Cycle to Cycle Battery Cell Degradation with High-Precision Measurements
## 2 Measurement Setup
### Investigation of Measurement Setup Performance  
It is very important to have a temperature stable measurement environment because the cell voltage and the internal resistance of the cell vary with the temperature [27; 29; 30]. This would cause the cycling time to vary slightly due to fluctuating temperature because the cell's upper and lower terminal voltage would be reached earlier or later depending on the temperature.  
The temperature stability of the measurement setup is demonstrated in Figure 3, where the air temperature has a standard deviation of less than \(\sigma_{\mathrm{Temp}}=7\,\mathrm{mK}\) (for an averaging time of 1 min). The cell temperature is affected by electrochemical processes in the cell, but due to the very constant ambient temperature, this temperature pattern is also very repeatable.  
Another important performance is the drift stability of the current measurement. The drift stability is determined by the cycler outputting a constant current of 0.9 A which is measured by a 7% digit benchtop multimeter. The current drift is shown in Figure 4, where the set value of 0.9 A was subtracted from the measured current. This reveals a current drift over a measurement period of one day of approximately 1.5 ppm, which is to be considered extremely low.  
Finally, it is important to know how much noise we have in our measurement result for the analysis we intend to use. Therefore, the capacity curve of an LG INR18650 MJ1 cell was measured at a current rate of C/4 (This means that each charging and discharging takes 4 h, hence the complete cycle has a duration of 8 h.) as shown in Figure 5.  
Figure 3: Temperature of the measurement hardware components (**top**) and cell temperature (**bottom**).  
The difference between the measuring points from Figure 5 is calculated, which corresponds to the slope of the curve and thus the differentiation of the same curve (see Figure 6). By differentiating the measured data, the noise component is also increased. In order to check whether the noise component is small enough to be able to determine the aging between consecutive cycles, the measurement data were approximated with an 8 th order polynomial. The results of the measurement curve and the approximation are shown in Figure 6. The difference between the approximation polynomial and the measured data results in the measurement noise being shown in Figure 7. Because the measurement noise with a standard deviation of \(\sigma_{\text{Noise}}=0.04\) mAh is lower by a factor of 25 than the capacity  
Figure 4: Current Drift over 24 h. The current samples were averaged over one minute. The current drift is approximately 1.5 ppm in 24 h.  
Figure 5: Reference measurement shows capacity decrease observed over the measurement cycles. For this purpose, an LG INR18650 MJ1 cell was cycled with C/4 at 40 \({}^{\circ}\)C ambient temperature.  
decrease (with at least 1 \(\frac{\mathrm{mAb}}{\mathrm{cycle}}\)), it can be concluded that the measurement data in Figure 6 are of excellent quality and trustworthy.
# Design and Dynamic Simulation Verification of an On-Orbit Operation-Based Modular Space Robot
## 2 Configuration Design of Reconfigurable Modular Space Robot
### Unit Module Mechanism Design
#### 2.3.3 System Assembly  
In this section, the designed parts are processed and assembled, and the power supply, motor, transmission mechanism, voltage reduction module, communication equipment, etc. are fixed and installed inside the structure in turn. The rotation of the motor is controlled to realize the mutual rotation of the active sub-module and the passive sub-module and experimentally verified to ensure that there is no limit to the attitude angle. The overall configuration is shown in Figure 12.
# Fast Converging Gauss-Seidel Iterative Algorithm for Massive MIMO Systems
## 4 Simulation Results and Analysis  
As a benchmark, MMSE detection algorithms are used to approximate optimal detection [29]. First, five iterative algorithms, GS, CPGS, PGS, and JAGS, have their bit error ratios (BERs) assessed in correlated and uncorrelated channels, respectively. The reference object used is the MMSE scheme. It functions very much the same as the greatest detecting system. Next, the CJGS iterative algorithm's starting parameters are simulated and investigated. In conclusion, an analysis was conducted to compare the computational complexity of the aforementioned techniques, where i denotes the number of iterations in the scheme.
# Routing Protocol for Heterogeneous Wireless Sensor Networks Based on a Modified Grey Wolf Optimizer
## 7 Conclusions  
In this study, we proposed a routing protocol for HWSNs based on a modified grey wolf optimizer. By defining different fitness functions for both advanced nodes and normal nodes and modifying the GWO, this algorithm can ensure that advanced nodes in the cluster are more likely to be selected as CHs. Consequently, the burden of low-energy nodes being selected as CHs can be reduced, and the network lifetime can be extended. The simulation results show that, compared with traditional SEP, DEEC, M-SEP, and FIGWO protocols, the energy consumption, lifetime, and throughput of the network are significantly improved. In the future, the proposed HMGWO will be extended to larger sensor networks to consider multi-hop communication between CHs, thus reducing energy consumption between a remote BS and CHs. However, when the CHs are selected, how to reasonably reduce the extra energy consumed by all sensor nodes to transmit their positions and energy to the base station, thus reducing the unnecessary energy consumption, will also be a focus of further study.  
[leftmargin=*] **Author Contributions:** X.Z.: Conceptualization, Investigation, Methodology, Project administration, Supervision, Writing--original draft. S.R.: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Validation, Visualization, Writing--original draft, Writing--review & editing. H.Q.: Investigation, Project administration, Software, Visualization. Q.G.: Formal analysis, Methodology, Project administration, Writing--review & editing. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the National Natural Science Foundation of China under Grant No. U1965102, the Science and Technology Innovation Team for Talent Promotion Plan of Shaanxi Province under Grant No. 2019 TD-028, the Special Planned Project for Serving Local Areas of Education Department of Shaanxi Provincial Government under Grant No. 18 JC029, and the Science and Technology Program of Xi'an under Grant No. 201806117 Yt05 NC13-2.  
The authors declare no conflict of interest.
## 3 Results and Discussion
### Rheological Testing  
Figure 2 presents the viscoelastic behavior of starch-based systems prepared with Paulownia extracts (i.e., bark, leaves, petioles) recovered using the lowest autohydrolysis temperatures, as representative of the tested systems developed with this biopolymer. In all cases, the elastic modulus (G') and viscous modulus (G\") remained practically constant with rising frequency. Moreover, elastic modulus was higher than the viscous one over the tested frequencies range. These tendencies indicated a typical gel behavior commonly found in similar biopolymer-based matrices [20; 24]. At fixed frequency, the highest magnitudes in viscoelastic moduli were identified for hydrogels enriched with extracts from petioles followed by those incorporated with bark and leaves. This is suggested to be related with the total solid content (g/100 g) present in the different tested Paulownia fractions, which varied from 20 to 33 for petioles, from 25 to 40 for banks, and from 36 to 43 for leaves [17]. Overall, the presence of _Paulownia_ extracts allowed the softening of starch-based matrices (around three times) in the absence of hydrothermal aqueous extracts. Even though, hydrogels with intermediate strength were identified in all cases. Above results were consistent with those previously reported for other similar biopolymer-based matrices [20; 25; 26] and those enriched with natural sources [24]. The latter authors stated that the softening of the hydrogels enriched with bioactive extracts could be explained by the competition by free water between the biopolymer-based matrix and the antioxidant extracts.