esa-sceva/satcom-chunk-collection huggingface dataset:
# A Comprehensive Review of In-Body Biomedical Antennas: Design, Challenges and Applications
## 4 Challenges That Influence the Design of In-Body Antennas
### Effect of Efficiency  
In a free space, the radiated power of an antenna depends on the far field elements only, as the near field is mostly reactive and therefore not distressing the radiated or the absorbed power [78]. In the case of an antenna radiating into lossy matter, the near field component plays a key role by causing strong coupling with the surrounding medium near to the antenna and hence increases the losses. Therefore, the total radiated power primarily depends on the radial distance \(r\). The outer boundaries of the near field and far field are commonly assumed as \(r<0.62\sqrt{D^{3}/\lambda}\) and \(r<D^{2}/\lambda\), where \(D\) is the antenna's highest dimension [84]. In the case of in-body antennas, the situation improves slightly because the complex lossy medium surrounding the antenna is of finite dimensions. In the lossy medium, strong coupling with nearby lossy biological tissues is caused by the radiated radio wave. Therefore, the coupling of frequency causes a loss of radiated power. This coupling is also the primary driver of lower radiation efficiency of in-body antennas. Furthermore, biocompatibility encapsulation using insulating materials plays a key role in reducing the coupling with the adjacent lossy environment [78].
## 4 Results and Discussion  
This study aims to classify the land covers in Tehran city with high accuracy using appropriate datasets and methodologies. A multi-spectral Landsat 8 image and SAR data (ALOS-2 and Sentinel-1) were used to evaluate the performance of the supervised classification algorithms, maximum likelihood and support vector machine. The comparison and evaluation of the results from the optical and SAR sensors are presented in the following.
# A Detailed One-Dimensional Hydrodynamic and Kinetic Model for Sorption Enhanced Gasification
## 2 SEG Process Description and Model Development
### Hydrodynamics
#### 2.3.4 Elutriation Rate  
When gas bubbles rise to the surface of the fluidized bed and break, solid particles are thrown into the freeboard and entrained by the upward gas volume flow [31]. While the major fraction of these particles fall back into the fluidized bed, small particles whose terminal velocity is lower than the gas velocity are elutriated from the freeboard [31].  
In the 200 kW facility, a cyclone is installed at the exit of the freeboard to reduce the extraction of bed inventory by leading the particles back into the fluidized bed [11]. It is assumed that there is an additional CO\({}_{2}\) capture effect in the freeboard: Due to lower freeboard temperatures, the position of the chemical equilibrium can be changed, which enables a further carbonation reaction. However, as bigger particles fall or are transferred back into the fluidized bed by the cyclone, it is assumed that only fine particles have a contribution to the additional carbonation reaction. According to [31], the elutriation rate of particles (in g/s) is described by  
\[\dot{M}_{dut}=k_{clut}x_{fine} \tag{14}\]  
Herein, \(k_{clut}\) is the elutriation rate constant and the weight fraction of fine particles, \(x_{fine}\), present in the bed was identified by measurements at the 200 kW facility. With a secondary cyclone, a mean particle size \(\overline{d_{p}}\) of 25 \(\upmu\)m of elutriated particles was found. Considering the particle size distribution of the raw limestone, it can be derived that fine particles do not originate from the make-up of the raw material. Thus, the source of these particles must be attrition or fragmentation effects. From experiments, a correlation was derived to calculate the weight fraction of the fine particles:  
\[x_{fine}=a_{1}\text{tanh}((u-a_{2})/a_{3})+a_{4}, \tag{15}\]  
with the parameters \(a_{1}=-0.12697\), \(a_{2}=0.71214\), \(a_{3}=-0.01191\), and \(a_{4}=0.12807\).
# A Real-Time Simulator for Navigation in GNSS-Denied Environments of UAV Swarms
## 3 Configuration of Simulator
### Monocular Camera  
A GNSS can supply global position and speed. Unfortunately, GNSS systems have been proven to be unreliable in multiple contexts [19]. As most of today's UAVs already have an onboard camera, computer vision has been widely researched as a potential solution to the problem. SMN [20; 21] is an absolute navigation algorithm that can obtain the position without external information. Such an approach performs matching of the images captured by the UAV with high-resolution geotagged satellite images or geotagged images from previous flights. In our simulator, we use a monocular camera to capture the images and use historical Google satellite maps as database images. The matching procedure will be introduced in Section 4. The parameters of the monocular camera are shown in Table 1.
# Multi-Stage Quantum Secure Direct Communication Using Secure Shared Authentication Key
## 5 Example of the Proposed Protocol
### Security Check Procedure
(2016) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Authenticated Quantum Key Distribution with Collective Detection using Single Photons. _Int. J. Theor. Phys._**2016**, _55_, 4238-4256. [CrossRef]
* [PERSON] et al. (2016) [PERSON]; [PERSON]; [PERSON]; [PERSON] Authenticated semi-quantum key distributions without classical channel. _Quantum Inf. Process._**2016**, _15_, 2881-2893. [CrossRef]
* [PERSON] (2014) [PERSON] Authentication Using Piggy Bank Approach to Secure Double-Lock Cryptography. _arXiv_**2014**, 1-8, arXiv:1411.3645. * [PERSON] and [PERSON] (2017) [PERSON]; [PERSON] [PERSON] A Shared Secret Key Initiated by EPR Authentication and Qubit Transmission Channels. _IEEE Access_**2017**, 17753-17763. [CrossRef]
* [PERSON] (2017) [PERSON] Multi-Photon Tolerant Quantum Key Distribution Protocols For Secured Global Communication. Ph.D. Thesis, University Of Oklahoma, Norman, OK, USA, 2017. * [PERSON] and [PERSON] (2015) [PERSON]; [PERSON]; [PERSON] Secure Satellite Communication Using Multi-Photon tolerant quantum communication protocol. In Proceedings of the Quantum Communications and Quantum Imaging XIII, San Diego, CA, USA, 1 September 2015; Volume 9615, p. 961509. * [PERSON] et al. (2019) [PERSON]; [PERSON]; [PERSON]. _Multi-Photon Quantum Secure Communication_; Springer: Singapore, 2019; ISBN 9789811086175. * _[PERSON] et al. (2016)_ [PERSON]; [PERSON]; [PERSON] Information Leakage Problem in Efficient Bidirectional Quantum Secure Direct Communication with Single Photons in Both Polarization and Spatial-Mode Degrees of Freedom. _Int. J. Theor. Phys._**2016**, _55_, 4681-4686. [CrossRef]
* _[PERSON] et al. (2014)_ [PERSON]; [PERSON]; [PERSON] Classification of quantum authentication protocols and calculation of their complexity. In Proceedings of the 15 th International Conference on Sciences and Techniques of Automatic Control & Computer Engineering, Hammamet, Tunisia, 21-23 December 2014; pp. 169-173. * _[PERSON] and [PERSON] (2011)_ [PERSON]; [PERSON] [PERSON] An Approach To Evaluate Quantum Authentication Protocols. In Proceedings of the Congresso Brasileiro de Inteligencia Computacional, Fortaleza, Brazil, 8-11 November 2011; pp. 1-8. * _[PERSON] and [PERSON] (2016)_ [PERSON]; [PERSON] Controlled quantum secure communication protocol with single photons in both polarization and spatial-mode degrees of freedom. _Mod. Phys. Lett. B_**2016**, _30_, 1650051. [CrossRef]
* _[PERSON] et al. (2016)_ [PERSON]; [PERSON]; [PERSON]; [PERSON] Three-party Quantum Secure Direct Communication with Single Photons in both Polarization and Spatial-mode Degrees of Freedom. _Int. J. Theor. Phys._**2016**, _55_, 2490-2499. [CrossRef]
# 2 CA-R2: A Hybrid MAC Protocol for Machine-Type Communications
## 6 Simulation Experiments and Results
### Network Throughput  
We can see in Figure 11 that when there are a few contending stations (between 1 and 20), the performance of 2 CA-R\({}^{2}\) starts with high figures but quickly decreases as the number of stations increases. After a certain point (approximately after 40 stations), its performance nearly does not change as the number of stations increases. Similar general trends are observed for both DCF and 2C-R\({}^{2}\), but the network throughput achieved by 2 CA-R\({}^{2}\) in all cases is greater than the one achieved by both of them. Furthermore, significant improvements are observed at both ends of the test conditions. With a large number of devices, for instance, the improvement that 2 CA-R\({}^{2}\) achieves over DCF is about 40%.
# Experimental Validation of Ellipsoidal Techniques for State Estimation in Marine Applications
## 5 Estimation Results
### Proof of Collision Avoidance  
As a final evaluation step, the position estimates according to Figure 8a are used to compute interval bounds for the distance of both boats that performed a synchronized motion during the measurement experiment. For this purpose, an interval-based distance computation is performed after enclosing the position ellipsoids into tight axis-aligned  
Figure 8: Localization of the DDboat A with heading and velocity measurement. (**a**) Evaluation of the system matrix in (55) for estimated heading information. (**b**) Evaluation of the system matrix in (55) for measured heading information. (**c**) Evaluation of the system matrix in (55) for measured heading information.  
Figure 9: Localization of the DDboat A with heading and velocity measurement, reduced number of measurements. (**a**) Evaluation of the system matrix in (55) for estimated heading information. (**b**) Evaluation of the system matrix in (55) for measured heading information.  
interval boxes. If this computation is performed purely on the basis of the predicted state information--see Figure 10--there exist some time intervals during the experiment in which a collision of the two boats cannot be ruled out with certainty (the value zero is included as the lower interval bound of the computed distances).  
Requesting the GPS position measurement during these phases and using the results of the innovation stage as shown in the previous subsection shows that the experiment from which the measurements were obtained is fully safe and that collisions of both boats can be ruled out with certainty within the considered bounds on the measurement uncertainty and the external disturbances identified in Section 4. As already mentioned in the previous subsection, an event-triggered estimation scheme can be used here as well to tighten the position bounds as soon as both boats approach each other and the predicted infima of the interval-based distance forecast fall below a specific threshold value.
# A Comparative Analysis of Anomaly Detection Methods in IoT Networks: An Experimental Study
## 2 Related Work in Anomaly Detection for IoT Networks  
Anomalies in IoT networks are deviations from the norm and can take different forms depending on the context [10]. In data science and AI, there are several main types of anomalies, which are described in Table 1.  
On this basis, the exemplary types of anomalies in IoT networks were classified, as illustrated in Figure 1.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Point Anomalies** & **Contextual Anomalies** & **Collective Anomalies** \\ \hline Single observations that differ significantly from the rest of the data. & Observations that are anomalies only in a specific context. & Groups of observations that together form a pattern that deviates from the norm. \\ \hline \hline \end{tabular}
\end{table}
Table 1: Types of anomalies (own elaboration).  
Figure 1: A simple example of anomaly classification in IoT networks, presented in the form of a diagram (own elaboration).  
Modern methods of detecting anomalies in network traffic are based on the combination of traditional techniques, such as outlier analysis and behavioral detection, with more advanced solutions, such as continuous monitoring and Intrusion Detection Systems (IDSs) [11; 12].The use of ML enables the automatic detection of new, unknown threat patterns, which is especially important in a dynamically changing network environment. These techniques enable proactive threat detection and adaptation to new, as yet unknown threat patterns [7; 9].
## 4 Task/Transmission Scheduling and Communication Protocols
### Communication Protocols
With the development of technology, the need for IPv4 address allocation has gradually increased, which has contributed to basically exhausting the entire pool of this addressing. In response to the introduction of the new IPv6 addressing standard and the need to handle packets containing such addresses, the 6 LowPAN routing protocol, which is characterized by a low power consumption, was created. The shortcomings of this protocol include the large size of the header relative to the data themselves; from the point of view of application considerations, the implementation of this protocol in RTIoT solutions can contribute to an increase in the level of latency or packet loss with a direct impact on the deterioration of QoS parameters. Today, further research is underway to address the challenges of the 6 LowPAN protocol, which include fragmentation, header compression and security [107].
## 2 Materials and Methods  
### Materials and Preparation of Samples  
The aqueous dispersions of flaxseed fiber (HiFood, Parma, Italy) were prepared at a concentration of 2.6 wt%. Based on details shared by the manufacturer, this fiber was obtained through an extraction procedure developed using proprietary methods (HIFOOD R&D Dept., Parma, Italy). It has a molecular weight of 1.47 kD and its chemical composition comprises mainly fiber (76 wt%) and a low proportion of carbohydrates (9 wt%) and proteins (4 wt%). In addition, it contains lipids (<2 wt%) and moisture (<7 wt%). Additionally, 0.1 wt% potassium sorbate (Sigma Aldrich, Madrid, Spain) was added as a preservative.  
Batches of 200 g of the sample were obtained by weighing the appropriate amounts of water and potassium sorbate, to which the calculated quantity of fiber was added. The mixture was then subjected to different treatments: (a) treatment U: 2 min of ultrasonic homogenization using a VCX750W (Sonics, Newtown, CT, USA) device at an amplitude of 40, 60, 80, or 100%, with 5 s on and 5 s off (samples U-2 min-40%, U-2 min-60%, U-2 min-80%, and U-2 min-100%, respectively), and (b) treatment LU: 4000 rpm for 2 min using the Ultraturrax T50 (IKA, Staufen, Germany) rotor-stator device with a S50 NG45F dispersion unit and subsequently, the resulting sample was submitted to ultrasonic homogenization at an amplitude of 100% and a time of 10 or 20 min (LU-10 min-100% and LU-20 min-100%, respectively), with 5 s on and 5 s off. A sample prepared with only the T50 device at 4000 rpm for 2 min (L-0 min) was used as a control in the LU treatment samples (results published in [44]). After preparation, the samples were kept under storage at about 4 \({}^{\circ}\)C until characterization.  
Table 1 shows the treatment applied to the aqueous dispersions of flaxseed fiber and the energy per mass unit applied. The energy applied during the ultrasonic homogenization process was provided by the device. The energy applied during the rotor-stator homogenization process was calculated as indicated in a previous work [44].
## 4 Discussion
CD44, CD45, CD73, CD90 and CD105 surface markers are essential for using MSC in orthopedic treatments to achieve osteogenic formation [27]. In our study, we used MSCs that express those surface markers. Although the decellularized omentum scaffold allowed cell adhesion and proliferation and the used MSCs had potential for osteogenic transformation, microscopic examinations and Salkeld scoring systems showed decreased bone healing and new bone formation. There are studies claiming direct injection of MSCs into critical bone defects and non-unions impairs healing [28]. When we looked at the mechanism which may have caused this, it was shown that bolus MSC could lead to a reduction in gene expression of Runt-related transcription factor-2 (Runx2) and Osterix pathway via TNF-\(\alpha\), which was responsible for the transformation of MSCs to osteogenic cells [29]. It is known that cumulative MSC expression causes a decrease in TNF-\(\alpha\)[30,31]. Scaffold applications with low doses of TNF-\(\alpha\) decreased osteogenic activation, and high doses of TNF-\(\alpha\) increased osteogenic activation in an experimental rat study [32]. The anti-inflammatory effect of cumulative MSC applications might have decreased TNF-\(\alpha\) levels in our scaffold and callus formation. This knowledge led us to speculate that this may be the reason for the impairment of osteogenic formations with MSC applications. Using xenogenic mesenchymal stem cells could be another reason for decreased healing. Although there are many studies that used xenogenic mesenchymal stem cells that caused no local or systemic rejections, there are also some controversial studies describing human mesenchymal stem cell apoptosis and fragmentation in immune-competent mice [33]. It has been reported that xenogeneic, MSC-derived chondrocytes trigger T lymphocyte proliferation, cytotoxicity, increasing antigen presentation and further activation of the adaptive immune response [34]. The possibility of localized immune reaction and diminishing mesenchymal stem cells may also explain impairment of osteogenic formation [35]. Radiologic results showed a correlation with our histologic results. We think that these correlations empower our study. However, our scaffold was not fully ossified and radiologic healing was not completely seen. There is no similar study in the literature to discuss how much time would be needed for radiological healing. One of the limitations of our study is the limited number of samples. Another limitation is that, although PRP is allogenic, MSCs are not. Due to technical drawbacks, rat-origin MSCs could not be used in our study. In addition, we did not investigate the important features of our scaffold, such as porosity and micro and nano construct.
## 3 Results and Discussion
### Ablation Study
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Method** & **F1/\%** & _mIoU_/\%** & **CC/GFLOPs** & **Par/M** & **Speed/FPS** \\ \hline SegFormer & 94.23 & 89.49 & 113.427 & 27.348 & 34.75 \\ SegFormer + MAM & 94.94 & 90.77 & 113.467 & 27.496 & 34.73 \\ SegFormer + TCUM & 94.83 & 90.49 & 176.316 & 28.767 & 28.35 \\ SegFormer + Mixed_Loss & 95.16 & 91.07 & 113.427 & 27.348 & 34.75 \\ SegFormer + MAM + Mixed_Loss & 94.84 & 90.51 & 113.467 & 27.496 & 34.73 \\ SegFormer + TCUM + Mixed_Loss & 95.20 & 91.12 & 176.316 & 28.767 & 28.35 \\ SegFormer + MAM + TCUM & 94.99 & 90.77 & 176.356 & 28.915 & 32.74 \\ ISTD-DisNet & 95.51 & 91.67 & 176.356 & 28.941 & 28.35 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Effectiveness of each module in ISTD-DisNet. not only improves the model's response to the distressed area and its ability to restore details but also effectively increases the completeness of the crack extraction.
## 5 Conclusions  
This research develops cluster head selection using K-medoids with ASFO and clustering and multihop routing protocol (CMRP) algorithms for efficient routing in WSNs. For optimal CH selection from suitable nodes, the K-ASFO approach can be used. The outcomes were compared using three standard metrics: throughput, residual power, and first dead node. Finally, the CMRP algorithm routing protocol is used for efficient data transfer. The routing process is permitted on recognized node-to-node paths. The simulation results demonstrate that the proposed system outperforms other existing algorithms.  
Figure 11: Comparison of jitter.  
The performance of the proposed methodology is compared to that of existing optimization-based routing algorithms. CMRP chooses the best path from the cluster head to the sink node. The proposed method is used to evaluate PDR, packet delay, throughput, power consumption, network lifetime, packet loss rate, and error estimation, and the results were superior to existing methods. PDR (100%), packet delay (0.05 s), throughput (0.99 Mbps), power consumption (1.97 mJ), network lifespan (5908 rounds), and PLR (0.5%) for 100 nodes are the performance results for QoS parameters. The proposed method has an overall accuracy of 93.19%. As a result, the proposed approach outperforms existing strategies in terms of overall performance. The proposed method produced better results in all scenarios and metrics. The proposed work was idealized, implemented, and tested against a static sensor node WSN. This research can be expanded to mobile sensor nodes or networks with sensors that can change position in real-time.  
Conceptualization: [PERSON] and T.T.; methodology: V.C.; validation: S.S.M.S., F.H. and A.K.M.; formal analysis: T.T. and R.S.; investigation: S.S.M.S. and F.H.; resources: F.H., V.C. and T.T.; data curation: [PERSON] and A.K.M.; writing--original draft preparation: [PERSON] and T.T.; writing--review and editing: [PERSON] and S.S.M.S.; visualization: V.C. and F.H.; supervision: [PERSON], [PERSON] and F.H.; project administration: S.S.M.S., R.S. and F.H.; funding acquisition: F.H. All authors have read and agreed to the published version of the manuscript.  
Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2023R236), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.  
Not applicable.  
The study did not report any data.  
The authors declare no conflict of interest.
# Mg,Sr-Cosubstituted Hydroxapatite with Improved Structural Properties
## 3 Results and Discussion
### Ion Exchange of Mg in Sr-HA Samples: \"Subsequent Mg Substitution\"  
#### 3.2.1 Development of the Process  
Ion exchange was previously found to be ineffective on stoichiometric sintered HA due to its low reactivity. Although ion exchange physiologically allows the incorporation of orally administered Sr into bone [12], previous attempts to replace Ca with Sr ions in HA were scarcely successful even with samples made of as-prepared, thermally untreated, and thus highly reactive, synthetic nanoapatites [36].  
The exchange of Mg ions for Ca in the HA lattice of sintered samples is extremely challenging as well because Mg is not prone to enter the HA lattice even during the wet synthesis of Mg-HA powder. Evidence of ion exchange of Mg or Sr with Ca in HA has been actually reported in the literature but mostly in the hydrated surface layer of the powder nanocrystals [25].  
To bypass this problem, we exploited the lattice defectiveness of sintered Sr-HA, and in particular, the HA cell expansion induced by Sr ions (which are bigger than Ca ions) to promote Mg exchange since Mg is smaller than both Ca and Sr.