esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results
By increasing the number of active elements while maintaining the position of the UAV at coordinate (90, 0, 20), Figure 5 shows the performance improvement in the proposed hybrid RIS-UAV in terms of the energy efficiency. The performance curve of the hybrid RIS-UAV is validated with the SNR equation of the hybrid RIS-UAV that shows the scaling factor of \(L^{2}\). As shown in Figure 5, the energy efficiency of the hybrid RIS-UAV increases in logarithmic growth as the number of active elements grows, and it matches with the performance of a fully active RIS-UAV once the number of active elements in the hybrid RIS-UAV is equal to the total number of elements, \(N\). Specifically, Figure 5 reveals that the proposed hybrid RIS-UAV outperforms the passive RIS-UAV, even with a small number of active elements. The proposed hybrid RIS-UAV is able to double the energy efficiency of the passive RIS-UAV by equipping it with only seven active elements and triple the performance of the passive RIS-UAV with 156 active elements. Finally, the energy efficiencies of different relaying schemes versus the total power budget are demonstrated in Figure 6. The result shows that if the total power budget is sufficient for the proposed active RIS-UAV to supply its hardware components, i.e., greater than 21 dBm, then the active RIS-UAV outperforms the other relaying schemes. This is in line with the observation in [26] for terrestrial RIS. In contrast, the half-duplex DF and AF UAV relays achieve the highest energy efficiency among the other schemes when the total power budget is smaller than 17 dBm. This is because the BS of the half-duplex UAV relaying scheme is only active half of the time; hence, more power is available to transmit the signals. However, as the total power budget increases, the hybrid and passive  
Figure 4: Energy efficiency versus number of antennas/elements at the M-MIMO UAV relay/ RIS-UAV. RIS-UAVs gradually outperform the half-duplex UAV relays because the RIS-UAVs can transmit and receive the signal simultaneously. In addition, the proposed hybrid RIS-UAV is able to achieve a higher energy efficiency than the passive RIS-UAV as it can amplify the attenuated signals and reflect them to the UE. As opposed to the active RIS-UAV that requires a larger power budget, the hybrid RIS-UAV can save up to 5 dBm while achieving an acceptable energy efficiency. The full-duplex UAV relays, however, are always the least energy-efficient relaying scheme due to the limitation of their residual self-interference. Moreover, it can be observed that the energy efficiency of the AF UAV relays is similar to the DF UAV relays because both relaying schemes are experiencing weak channel links between the BS and the UAV relay. Nonetheless, the energy efficiencies of all the relaying schemes decrease gradually once the total power budget is sufficient to transmit the signals because the energy efficiency is the ratio of the achievable rate to the total power consumption. Figure 5: Energy efficiency versus the number of active elements in the hybrid RIS-UAV. Figure 6: Energy efficiency versus total power budget.
# Miniaturized MIMO Antenna Array with High Isolation for 5G Metal-Frame Smartphone Application
## 3 Results and Discussion
### Comparison and Discussion  
To further demonstrate that the proposed work is better in design and performance, a detailed comparison of this work with the available work is conducted and illustrated in Table 1. It is worth mentioning that based on different analyses, investigations, and studies, we believe that the proposed model has the potential to be a useful MIMO system for future 5G smart mobile terminals.  
First, all bandwidths are -6 dB impedance bandwidth, which is carefully extracted from these articles. The data that is superior to the proposed MIMO antenna is painted in green color. The proposed antenna is with unique features at least from one aspect: isolation, ECC, or size.  
Compared with all the listed projects, the proposed antenna design has low complexity and is convenient for future practical applications. Although the proposed MIMO antennas are worse bandwidth than the reference antennas in [20; 21; 22; 44], and worse isolation and ECC than the latest literature [42], these references are with a larger size or even with a greater design complexity simultaneously. The antenna distance of different works is also added in Table 1. The proposed design is not the antenna pair and uses spatial diversity to improve isolation, so the antenna distance is larger than the other works'.  
In a word, the proposed MIMO antenna makes a good compromise between bandwidth, isolation, and size and exhibits better performance than most of the MIMO antennas reported in Table 1.  
Figure 19: Simulation results of the proposed MIMO antenna with a right-hand model. (**a**): Reflection coefficients with a right-hand model, (**b**): transmission coefficients with a right-hand model, (**c**): total efficiency with a hand model, and (**d**): SAR with a right-hand model.
## 3 Results and Discussion  
### Characteristics of the Biomass-Derived Adsorbent  
The prepared biomass-derived adsorbent was examined with SEM and various magnifications of 2000 and 3000 as shown in Figure 1,B, respectively. The biomass-derived adsorbent has clear pores in the micro size, and the material surface is rich with edges and layers. The EDS analysis (Figure 2) indicates the presence of C and O as the main components, as well as Al, Si, S and P as minor components, which may contaminate the materials because of the waste origin of this biomass-derived adsorbent. The BET surface area for nitrogen adsorption/desorption was determined to be around 4.9462 m\({}^{2}\)/g. Although the fabricated adsorbent has a relatively low surface area, the presence of groups containing electronegative atoms such as O, S and P enhances the tendency for heavy metal adsorption and enables real application for extraction purposes [33; 34].  
Figure 1: SEM images of the biomass-derived adsorbent at various magnifications of 2000 (**A**) and 3000 (**B**).  
The X-ray diffraction to characterize the structural nature of the prepared biomass-derived adsorbent was performed, and peaks are shown in Figure 3. The original palm waste (Figure 3A) and the biomass-derived adsorbent (Figure 3B) showed mainly amorphous structure, with two broad peaks at two theta of 16 and 25 related to the cellulosic content [35]. In addition, the surface functional groups were analyzed with FTIR spectroscopy as shown in Figure 3. The peaks related to OH groups were detected between 3300 and 3500 cm\({}^{-1}\) in both the original palm waste (Figure 4A) and the biomass-derived adsorbent (Figure 4B). In addition, the aliphatic CH group was detected at around 2900 cm\({}^{-1}\), C=C appeared at about 1640 cm\({}^{-1}\) and the carbonyl group appeared at about 1700 cm\({}^{-1}\). The peaks detected at 1035 and 560 cm\({}^{-1}\) may be attributed to PO4\({}^{-3}\) groups [36], which contaminated the palm waste. These surface-active groups are expected to enhance the adsorption [34] process and the application to extraction using adsorption/desorption procedures.  
Figure 3: XRD of the original palm waste (**A**) and biomass-derived adsorbent (**B**).  
Figure 2: EDS of the biomass-derived adsorbent.
## 2 Exosome Features  
### Extracellular Vesicle Classification  
The International Society for Extracellular Vesicles (ISEV) [8], founded in 2011, has been created to generate a consensus on the classification of extracellular vesicles. Extracellular vesicles are classified according to their size, and there are three important groups: exosomes with sizes of 30-200 nm, microc vesicles of 100-1000 nm, and apoptotic bodies with a size greater than 1000 nm [2]. Each EV type is synthesized using distinct cellular mechanisms. Exosomes originate from the late endosomal system and are formed within multivesicular bodies called intraluminal vesicles (ILVs). This process requires two important processes. First, the endosome membrane is enriched with tetraspannis and then recruits the endosomal sorting complex required for transport (ESCRT) complexes for their ubiquitination and subsequent release [4]. The formation of microc vesicles occurs in areas of membrane invagination [9], while the formation of apoptotic bodies in cells destined to die occurs for faster elimination of apoptotic cells. Apoptotic bodies are generated by Bax and Bak, components of Bcl-2 that mediate the intrinsic pathway of apoptosis, which generates pores in the outer mitochondrial membrane. Intermembrane components, including caspases, are released through these pores, initiating apoptosis [10].  
Different aspects of these vesicles have been investigated, including the mechanisms associated with their formation, the sites of their release, multivesicular bodies (MVBs), and late endosomes, which are specialized endosomal compartments rich in (ILVs) that sequester specific proteins, lipids, and cytosolic components. ILVs, which become exosomes upon secretion, are formed through the inward budding of endosomal membranes, a process first identified in studies of transferrin receptor (TfR) secretion in mature reticulocytes [11]. It is undergoing its most recent update in 2023, which includes specific recommendations for characterization technologies and release and uptake studies of EV. Its therapeutic applications and mechanisms of action of EV are advanced in areas such as neurodegeneration, cancer, and aging.
# Underwater Drone Architecture for Marine Digital Twin: Lessons Learned from SUSHI DROP Project +
## 2 Materials and Methods
### Mission Survey
#### 2.4.1 MBES Survey  
Using MBES, it is possible to scan a large area [48] in a short time. At this stage Blucy can be piloted in both navigation modes, ROV or AUV, because it navigates at constant depth and is not affected by surface currents or wave motion. At the same time it is always at a safe distance, away from the seabed, avoiding any interference with it. The 3D reconstruction resulting from these acquisition could allow to identify hot-spots, areas of limited extension, in which perform further close seabed inspection using optical sensors, increasing the level of detail and knowledge of the area surveyed. It is important to highlight that the MBES is independent of the visibility conditions of the water and relative turbidity.  
The following factors were considered when planning a survey with the MBES:  
* The geography and extension of the survey area;
* Suitable areas for calibration patch test;
* Echo sounder coverage;
* Seabed topography;
* Sound Speed variations;
* Weather conditions.  
In MBES survey, the operator has to plan the surveys lines carefully based on swath coverage that defines the multibeam system. The survey lines should be designed so that there is at least 80% overlap in coverage between adjacent lines. As swath width is a function of distance from the seafloor, it follows that the spacing between the lines may not be constant. The planning survey lines are designed with a trade off between Blucy navigation depth, seabed morphology (slopes, rocky formations), seabed type (grain size characteristics of the seabed) and swath width. With MBES the lines are planned to be perpendicular to slope directions to maintain a constant swath coverage. Even if navigation takes place at a depth for which surface currents can be considered negligible and maintaining an attitude aligned to the seabed with zero pitch and roll, it is still useful to calibrate the offsets regarding MBES according to the following procedure:  
* Roll: two lines over a flat area in opposite direction with the same speed;
* Pitch: two lines over an area with slopes (or an object) in opposite directions with same speed;
* Heading: two lines over an area with slopes (or an object), the lines need to overlap half a swath width, in same direction with same speed.
# The Wettability and Numerical Model of Different Silicon Microstructural Surfaces
## 2 Surface Properties of Silicon Prepared by PIII Technology
### Static Contact Angle of the Sample Surfaces  
The static contact angle of the sample surfaces was measured by the contact angle measuring instrument XG-GAMB1 (Xuanyichuangxi Industrial Equipment Co. Ltd., Shanghai, China). Ultrapure water with a volume of 2 \(\upmu\)L was used as the experimental working medium, and the environmental temperature was set at 20 \({}^{\circ}\)C. The static contact angle measuring instrument was used to measure the contact angle of the sample surface using the height-width method. To reduce accidental error of the sample surface damage or surface structure non-uniformity, the contact angle was analyzed in at least three regions for each sample. The static contact angle results are shown in Figure 6.  
Figure 6 exhibits a significant increase in the contact angle of the sample surface prepared by PIII technology. In addition, the hydrophilic surface was transformed into a hydrophobic surface (the contact angle was greater than 90\({}^{\circ}\)). Figures 3 and 4 present a combination of the SEM and AFM surface morphologies, wherein sample 2 exhibited minimal changes in its surface morphology as compared to sample 1, whereas the contact angle exhibited significant changes because the intensity of the etching reaction was not enough to form an obvious microstructure on the surface of the sample at a low gas mixing ratio. However, the reaction continued to change the chemical properties of the surface of the sample, thereby generating a change in the wetting properties of the surface. An increase  
Figure 5: Variation of the area ratio and surface roughness with the mixing ratio of the gases.  
Figure 6: Variation of the contact angle with the mixing ratio of the gases.  
in the mixing ratio of the gases generated an increase in the value of the static contact angle of the surface, though this growth rate of contact angle gradually decreased. A combination of the previous figures with Figure 5 exhibited a simultaneous increase in the area ratio and roughness of the sample following an increase in the mixing ratio of the gases from 1:1 to 3:1. When the gas mixture ratio was greater than 3:1, the roughness exhibited a slight decrease, even when following an increase in the convex/concave area ratio. Therefore, the increased surface roughness (Ra) and area ratio (r) generated an increase in the contact angle. When the mixing ratio of the gases was less than 3:1, an increase in both the roughness and area ratio resulted in a significant increase in the contact angle. In addition, a gas-mixing ratio greater than 3:1 inhibited the increase of the contact angle due to the decrease in the roughness, thereby decreasing the growth rate of the contact angle under the condition of a large mixing ratio.
## 4 Validation Results via Simulation
### Semiconductor Voltage Stress Comparison  
A further analysis was done by reviewing the maximum, minimum and average semiconductor voltage stress for inverter operating with the two studied standards using the same simulations producing Figures 11 and 13. In addition to the two methods compared in these figures, the proposed control without adding the harmonic components in the voltage references is also assessed. In Table 7, the minimum voltage corresponds with intervals in which the input voltage is minimum (125 V-25%), the maximum voltage corresponds to the intervals in which the input voltage is maximum (125 V + 25%) and the average is computed considering the complete simulation interval for both standards.  
Figure 12: Simulated waveforms during experiment 2 using the proposed DS-SMC.  
Results demonstrate how the voltage stress of the semiconductors reduces considerably by employing the DS-SMC proposed in this study (Separate voltage control loops minimizing the DC-bias of the references) even without additional harmonic components into the voltage references. Beyond that, results also demonstrate conclusively how the addition of the two harmonic components in the references further improve this feature.
# Influence of CeO\({}_{2}\) Addition to Ni-Cu/HZSM-5 Catalysts on Hydrodeoxygenation of Bio-Oil
## 4 Conclusions  
This study on the addition of different CeO\({}_{2}\) contents to the Ni-Cu/HZSM-5 catalyst used for the HDO of bio-oil derived the following conclusions:  
1. The effect of bio-oil HDO can be improved by adding CeO\({}_{2}\). The upgrading oil yield can reach a maximum of 47.6% when the CeO\({}_{2}\) content is 15%. From the energy utilization perspective, 270 \({}^{\circ}\)C is the suitable temperature for HDO when the CeO\({}_{2}\) content is 15% of the Ni-Cu/HZSM-5 catalyst.
2. The addition of CeO\({}_{2}\) can improve the Ni dispersion and redox ability, can increase the Bronsted acidity ratio, and can decrease the particle size of the catalyst. When the CeO\({}_{2}\) content is 15%, the performance of the catalyst is at the optimum, the particle size of active metal is the smallest, the dispersibility of active metal is the best, the ratio of Bronsted acids to total acids is the largest, and the reduction temperature of H\({}_{2}\)-TPR is the lowest. In addition, the reduction of the specific surface area and the pore loss of the catalyst after the reaction is the smallest compared with that of the catalyst before reaction.
3. The addition of CeO\({}_{2}\) can improve the coke deposition of deactivated catalysts after HDO. The catalyst carbon deposit resistance is at the optimum when the CeO\({}_{2}\) content is 15%. Comparedwith the catalyst without CeO\({}_{2}\), the coke deposition decreases from 41 to 14 wt%. At this CeO\({}_{2}\) content, the temperature of the exothermic peak of the coke combustion is also the lowest, therefore proving that the soft coke formed at this time is a derivative with a relatively small molecular weight.  
Conceptualization, C.Z. and R.Z.; validation, W.W.; investigation, W.W. and G.C.; resources, R.Z.; writing--original draft preparation, W.W.; writing--review and editing, C.Z., W.W., R.Z., and G.C.  
This research was partially funded by the National Key Research and Development Program of China, grant number 2017 YFC0212400.  
The authors declare no conflict of interest.
# HMM Adaptation for Improving a Human Activity Recognition System
## 6 Conclusions  
This work has proposed a user adaptation technique for improving a HAR system based on HMMs. This system segments and recognizes six different physical activities (walking, walking upstairs, walking downstairs, sitting, standing and lying down) using inertial signals from a smartphone. The system is composed of a feature extractor for obtaining the most relevant characteristics from the inertial signals, a module for training the six HMMs (one per activity), and the last module for segmenting new activity sequences using these models. This paper has evaluated two different HMMs training strategies: the first one, a generative approach (Maximum Likelihood Estimation), and the second, a discriminative one (Maximum Mutual Information Estimation). The discriminative training strategy (MMIE) obtains slightly better results, although the differences are not statistically significant.  
The main contribution of this paper is the analysis of a user adaptation technique for adapting the HMMs to the user who performs the different activities. The user adaptation technique consists of a Maximum A Posteriori (MAP) approach. The final results on a public dataset [30] have reported significant error rate reduction: from 3.2% to 2.0% ARER (more than 30% relative error rate reduction). In conclusion, adapting a HAR system to the user who is performing the physical activities reports significant improvement in the activity segmentation process.  
This work has been supported by ASLP-MULAN (TIN2014-54288-C4-1-R) and NAVEGABLE (MICINN, DPI2014-53525-C3-2-R) projects.  
[PERSON] implemented the HAR system using HMMs, executed the experimental work for the adaptation process, analyzed the results, drafted the initial manuscript and revised the manuscript. [PERSON] conceptualized the HMM adaptation process, supervised the experiments and revised the manuscript. [PERSON] integrated the discriminative training procedure, executed the experiments related to discriminative training, helped to draft the initial manuscript and revised the final version. [PERSON] analyzed the results, provided feedback and revised the final manuscript.  
The authors declare no conflict of interest.
## 3 Results and Discussion
Electrons in CB transfer from rutile to anatase because EA\({}_{\text{A}}\) was higher than EA\({}_{\text{R}}\) while holes transfer from anatase to rutile [41; 43; 44]. Considering the kinetic constant of TiO\({}_{2}\)-300 (\(2.54\times 10^{-2}\) h\({}^{-1}\)) and TiO\({}_{2}\)-700 (\(6.67\times 10^{-2}\) h\({}^{-1}\)), the mixture of anatase and rutile (TiO\({}_{2}\)-700) provided higher photocatalytic activity than that of anatase and brookite (TiO\({}_{2}\)-300). It was observed that the weight percentage of anatase phase of TiO\({}_{2}\)-700 (38%wt.) was higher than that of TiO\({}_{2}\)-300 (29%wt.) while the crystallite size of TiO\({}_{2}\)-300 was smaller than that of TiO\({}_{2}\)-700. High crystallinity of the mixture of anatase and rutile phases provided higher photocatalytic activity than that of the mixture of anatase and brookite phases because it has been reported that TiO\({}_{2}\) comprising the brookite phase of more than 25% could inhibit photocatalytic activity of TiO\({}_{2}\)[45]. At calcination temperature of 800 \({}^{\circ}\)C, it shows the lowest kinetic constant of \(2.19\times 10^{-2}\) h\({}^{-1}\) because TiO\({}_{2}\)-800 consisted of only rutile phase and had the largest crystallite size of 52 nm. Due to the direct band gap structure of the rutile phase, there is the fast recombination of e\({}^{-}\)-h\({}^{+}\) pairs as shown in Figure 6e leading to the lowest photocatalytic activity of TiO\({}_{2}\)-800. These results correlated well with the study of [PERSON] et al. [46] who found that photocatalytic activity of H\({}_{2}\) evolution of the pure rutile phase was lower than that of the mixture of anatase and rutile phases. \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline \multicolumn{1}{c}{Calcination Temperature (\({}^{\circ}\)C)} & 300 & 400 & 500 & 600 & 650 & 700 & 800 & P25 \\ \hline Kinetic constant (k \(\times\) 10\({}^{-2}\)) (h\({}^{-1}\)) & 2.54 & 3.87 & 4.86 & 9.46 & 7.73 & 6.67 & 2.19 & 11.41 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Kinetic constant (k) of MB degradation obtained when using synthesized TiO\({}_{2}\) powder with different calcination temperatures. Figure 5: **(a)** The adsorption change of methylene blue (MB) in the dark and photocatalytic degradation of MB under UV light for 2 h with the synthesized TiO\({}_{2}\) and P25. **(b)** Photocatalytic degradation of MB under UV light obtained when using synthesized TiO\({}_{2}\) with different calcination temperatures.