esa-sceva/satcom-chunk-collection huggingface dataset:
## 1 Introduction
The SSV is classified into Medium Earth Orbit (MEO) SSV and High Earth Orbit (HEO)/Geostationary Earth Orbit (GEO) SSV based on an altitude of 8000 km. In the MEO SSV, GPS signals from more than four satellites can be received, and accuracy at a level of 1 m precision can be obtained. In the HEO/GEO SSV, signals transmitted from the opposite of the earth are utilized, and a section of GPS signal outage occurs. Furthermore, the signal strength in the HEO/GEO SSV is lower than that of the TSV and MEO SSV. Nonetheless, it has been known to have a position accuracy within 100 m [1]. Such results are basically due to the lack of enough visible satellites for navigation in SSV. Thus, regarding this problem, using interoperable multi-GNSS in SSV has been  
Figure 1: The geometry of GNSS signals in Space Service Volume (SSV). studied with respect to a significant advantage in visibility [13; 14]. In addition, since a large region of the main lobe signal is not received due to the shadowing effect, a method of utilizing the side lobe signal is presented [13; 15]. Using a broader beam-width and complementary radiation pattern due to the difference between L1, L2, and L5 signals also benefits visibility [15; 16]. Furthermore, to deal with weak signals in SSV, authors in [17] studied a four-state Kalman filter and Inertial Navigation System (INS) aiding open loop tracking strategy for a receiver algorithm. Many studies on transmitting antennas also have been conducted, such as using different transmission antenna patterns for various conditions in SSV [18] or emphasizing the importance of side lobe transmission antenna modeling to use a side lobe signal in SSV [19]. In [20], taking into consideration the L1 and L5 frequency bands of GPS and Galileo, the processing of different GNSS signals, with the goal to determine the best navigation performance for the GEO mission, was investigated. An analysis of the effect of non-Medium Earth Orbit (non-MEO) GNSS satellites on the GEO mission is also needed. An interim result of the analysis on this was presented [21]. In particular, the effectiveness of the utilization of the first side-lobe signals for KPS satellites were analyzed recently [22]. In this study, the possibility of GNSS signal utilization according to a longitude of geostationary satellites is analyzed. In this study, a means of ensuring the GNSS satellite visibility by utilizing multi-GNSS and first side lobe signals is presented. To analyze GNSS signal utilization performance, GDOP and link-budget are introduced and simulated to represent User Equivalent Range Error (UERE) and position estimation results. All results are analyzed according to the longitude of the GEO. Since the visibility of non-MEO satellites have a significant effect on position accuracy, performances are compared by dividing the area according to whether BDSs are non-MEO satellites. Through this study, the applicability of GNSS signals in the space mission is investigated. In particular, the analysis is focused on the applicability of GNSS signals of geostationary orbit satellites located over the Korean Peninsula.
# A Dynamic Analysis Method of Liquid-Filled Containers Considering the Fluid-Structure Interaction
## 5 Conclusions  
A dynamic analysis was performed on liquid sloshing modes in liquid-filled containers and the liquid-filled containers themselves using the FEM based on acoustic fluid elements. The following conclusions can be drawn:  
1. The liquid sloshing modes in 2D and 3D liquid-filled containers of regular shapes and arbitrary cross sections were analyzed and compared with theoretical solutions and test results. The results reveal that the FEM based on acoustic fluid elements is accurate;
2. The liquid level exerts significant influences on the intrinsic frequency of liquid-filled containers. As the liquid level in liquid-filled containers rises, the vibration frequency of cylindrical containers decreases. When the liquid level in liquid-filled containers is 6 m, the first frequency decreases by 31.24%. During the engineering design of such liquid-filled containers, the influence of the effect of FSIs on the intrinsic frequency of these containers should not be ignored. FEM based on acoustic fluid elements can be used to model such an effect;
3. For the cylindrical liquid-filled containers in this research, the liquid level essentially did not influence the displacement, acceleration, and stress of the liquid-filled containers under horizonal seismic action if the liquid level was low. As the liquid level rises, the displacement and acceleration of, and stress on, such liquid-filled containers increase  
Figure 30: The distribution of \(\mathrm{R}_{\sigma}\) on the sidewall of containers. (**a**) El-Centro wave. (**b**) Kobe wave. (**c**) Loma Prieta wave.  
significantly. The acceleration responses of liquid-filled containers are particularly significantly affected by the spectral characteristics of the input seismic wave.  
Conceptualization, X.F. and X.B.; methodology, X.F.; software, X.F.; validation, F.Y., Q.Z. and X.B.; formal analysis, X.F.; investigation, Q.Z.; resources, X.F.; data curation, X.B.; writing--original draft preparation, X.F.; writing--review and editing, X.B.; All authors have read and agreed to the published version of the manuscript.  
This research was funded by [Hainan Special PhD Scientific Research Foundation of Sanya Yazhou Bay Science and Technology City] grant number [HSPHDSRF-2022-03-008].  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The author is very grateful to [PERSON] for his careful guidance of this paper.  
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
# Machine Learning Approach for Personality Recognition in Spanish Texts
## 3 Supervised Learning Model to Classify Texts
### Feature Selection  
The dataset is composed of a total of 546 features (540 features representing verbs and adjectives in the text documents, and 6 features representing the demographic data) and a personality label.  
Commonly, raw data contains a combination of features, some of which are irrelevant since they do not provide information to the prediction process. The feature selection process takes a subgroup of related features to be included in the training of a learning model. Feature selection techniques are useful because they simplify models and reduce training time. Feature selection aims to establish redundant or irrelevant features which can be eliminated without losing information [10]. We applied two feature selection methods in order to have several versions of the dataset.  
We used the correlation feature selection method with a Ranker search. This method evaluates the worth of a feature by measuring the Pearson's correlation between it and the class [30]. This method generated a ranked list of the 546 features.  
We also used the Info Gain feature selection method with the Ranker search. This method evaluates the worth of a feature via the information gain with respect to the class. Information gain is computed by the contribution of the feature in decreasing overall entropy [31]. The Info Gain method produced a ranked list of the 546 features.  
Additionally, for feature subset selection, we experimented with Wrappers and several classifiers (e.g., AdaBoost and random forest). The Wrappers method evaluates sets of features by means of a learning scheme [32]. However, few features were selected by the Wrappers method; at most, 35 features were selected. Therefore, there was a significant loss of information and the performance of the machine learning decreased.  
Cross validation is used to estimate the accuracy of the learning scheme for a set of features. Based on the results of the feature selection process, we built eight datasets from the original dataset. The datasets are detailed below.
# Oral Immunotherapy with Standardized Peanut Extract: A Game-Changer for Peanut Allergy
## 3 Results
### Safety Considerations and Mitigating Adverse Events  
Every OIT protocol deliberately involves ingesting known quantities of allergens. Therefore, adverse events are virtually inevitable (Figure 1). The most reported reactions--abdominal pain, oral itching, and throat irritation--tend to occur during the initial up-dosing phase [1]. Adherence to strict dosing regimens, patient education regarding the importance of interrupting therapy during illness or after vigorous exercise, and clear instructions on when to use epinephrine autoinjectors are essential for risk control [10]. In the ARC008 study, patients who continued PTAH therapy for up to five years generally maintained or improved their tolerance levels, safely ingesting amounts of peanut protein previously considered dangerous. The frequency and intensity of adverse events also declined over time, suggesting that ongoing exposure can lead to greater comfort and stability in daily dosing [26].  
In this setting, severe allergic reactions remain rare, especially once patients reach their maintenance dose. Rigorous patient selection further improves safety: patients with uncontrolled asthma, for example, may not be ideal candidates until their respiratory condition stabilizes [15].  
Additionally, while eosinophilic esophagitis (EoE) affects about 1% of patients undergoing peanut OIT, the early recognition of specific symptoms like dysphagia and chest pain can prompt timely intervention [28]. If EoE develops, the adjustment or discontinuation of therapy may be required. Future studies should aim to identify high-risk patients for such complications, possibly through genetic or immunological markers, to tailor preventive strategies [29].  
Recognized risk factors for adverse events during OIT encompass uncontrolled asthma, younger age, baseline reactivity at very low doses, and concurrent viral infections. Diligent patient selection, the pre-treatment stabilization of comorbid conditions, and education regarding symptom recognition constitute critical mitigation strategies. Complementary therapies, such as anti-IgE (omalizumab), have demonstrated potential in diminishing reactions and enhancing tolerability during dose escalation [30]. A personalized risk-benefit assessment and shared decision-making are fundamental components of OIT protocols [1].
# Multiport Single Element Mimo Antenna Systems: A Review
## 5 Summary
In Proceedings of the 2017 Sixth Asia-Pacific Conference on Antennas and Propagation (APCAPCAP), Xi'an, China, 16-19 October 2017. * _[PERSON] et al. (2013)_ [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON], S.S. Compact Low-Profile Dual-Port Single Wideband Planar Inverted-F MIMO Antenna. _IEEE Antennas Wirel. Propag. Lett._**2013**, _12_, 1673-1675. [CrossRef]
* _[PERSON] et al. (2017)_ [PERSON]; [PERSON]; [PERSON] UWB MIMO antenna with common radiator. _Int. J. Microw. Wirel. Technol._**2017**, \(9\), 573-580. [CrossRef]
* _[PERSON] et al. (2015)_ [PERSON]; [PERSON] Compact dual band-notched UWB mimo antenna with shared radiator. _Microw. Opt. Technol. Lett._**2015**, _57_, 2886-2891. [CrossRef]
* _[PERSON] et al. (2014)_ [PERSON]; [PERSON] Compact Coradiator UWB-MIMO Antenna With Dual Polarization. _IEEE Trans. Antennas Propag._**2014**, _62_, 4474-4480. [CrossRef]
* _[PERSON] et al. (2015)_ [PERSON]; [PERSON]; [PERSON] Compact 4-port ACS-fed UWB-MIMO antenna with shared radiators. _Prog. Electromagn. Res. Lett._**2015**, _55_, 81-88. [CrossRef]
* _[PERSON] et al. (2019)_ [PERSON]; [PERSON] Multi-cut four-port shared radiator with stepped ground and diversity effects for WLAN application. _Int. J. Microw. Wirel. Technol._**2019**, _11_, 1044-1053. [CrossRef]
* _[PERSON] et al. (2020)_ [PERSON]; [PERSON] Four-port shared rectangular radiator with defected ground for wireless application. _Int. J. Commun. Syst._**2020**, _33_, e4356. [CrossRef]
* _[PERSON] et al. (2014)_ [PERSON]; [PERSON]; [PERSON] Common Elements Wideband MIMO Antenna System for WiFi/LTE Access-Point Applications. _IEEE Antennas Wirel. Propag. Lett._**2014**, _13_, 1601-1604. [CrossRef]
* _[PERSON] et al. (2018)_ [PERSON]; [PERSON]; [PERSON] Modified circular common element four-port multiple-input-multiple-output antenna using diagonal parasitic element. _Int. J. RF Microw. Comput. Eng._**2018**, _29_, e21527. [CrossRef]
* _[PERSON] et al. (2016)_ [PERSON]; [PERSON]; [PERSON] High isolation, dual-polarized & dual-band single-layer differential MIMO antenna for WiMAX application. In Proceedings of the 2016 IEEE International Symposium on Antennas and Propagation (APSURSI), Fajardo, PR, USA, 26 June-1 July 2016. * _[PERSON] et al. (2017)_ [PERSON]; [PERSON] Design of wideband MIMO antenna for wireless applications. In Proceedings of the 2017 25 th Signal Processing and Communications Applications Conference (SIU), Antalya, Turkey, 15-18 May 2017. * _[PERSON] et al. (2017)_ [PERSON]; [PERSON]; [PERSON] Single radiator four-port MIMO antenna for WLAN and WiMAX applications with high isolation. In Proceedings of the 2017 IEEE 5 th International Symposium on Electromagnetic Compatibility (EMC-Beijing), Beijing, China, 28-31 October 2017. **Disclaimer/Publisher's Note:** The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.
# On the Performance of Partial LIS for 6G Systems
###### Abstract  
One of the key technologies of 6G communications relies on large intelligent surfaces (LIS), which can be viewed as a near-field beamformer that is supportive of extremely high symbol rates and enables a high level of interference avoidance. This article focuses on LIS systems, analysing the impact of the use of a whole LIS system or a subset of an antenna array. We analyse an LIS system associated with a single carrier with frequency domain equalization (SC-FDE), and with different receiver types of varying complexities. Because it is a function of the number of antennas, the computational complexity decreases when antenna elements that are closer to the user equipment are used instead of the whole LIS. Moreover, with a partial LIS, a reduction of energy consumption is achieved, and mitigation of the interference levels is obtained, allowing a performance very close to that obtained with the whole LIS system.  
LIS systems; 6G; SC-FDE; receiver types +
Footnote †: journal: Electronics Letters  
0000-0001-6000-0001-6000][PERSON]  
1,2,3,4,*  
* [1][PERSON]  
5 Faculty of Sciences and Technology, Universidade Nova, 2829-516 Caparica, Portugal; [EMAIL_ADDRESS] Department of Information Science and Technology, ISCTE-Instituto Universitario de Lisboa, 1649-026 Lisboa, Portugal; [EMAIL_ADDRESS] Department of Information Science and Technology, ISCTE-Instituto Universitario de Lisboa, 1649-026 Lisboa, Portugal 6
## 3 RTI Data Acquisition Methods
### Gravity Methods  
Gravity Surveys (GS) use portable gravimeters [63], placed at regularly spaced sampling locations, to measure subtle variation in gravity surrounding railway tunnels [64]. Anomalies observed in returned Complete Bouguer Anomaly (CBA) curves inform subsurface material composition [65] and indirectly, structural health assessment. Regional trends in subsurface density conveyed by CBA curves can vary across scales comparable to the tunnel itself, granting extensive inspection coverage. Likewise, localised negative field displacements can indicate the presence of irregular low density regions, strong indicators of voids and deformation zones [66; 67; 68]. However, few common defects exhibit substantially large density variations (compared to their surrounding landmass) that would noticeably influence a CBA curve, which despite informing the general nature of the subsurface, does not comprehensively nor clearly visualise subsurface features themselves. Moreover, localising large features relative to the tunnel (i.e., in front, behind, left, right) is further complicated by the structure's cylindrical profile. This makes modelling the corresponding gravity field a multi-solution problem, introducing significant uncertainty and greatly increasing involved computation efforts [69].
## 2 Experiment Setup
### Displacement and Aerodynamic Force Measurement  
Two CCD laser displacement sensors (LK-G400, KEYENCE Company, Itasca, IL, USA) were fixed under both sides of the torsion axis of the model bilaterally, which were employed to measure the vertical and torsional displacement. The reference distance of sensors was 400 mm, and the measuring range was \(\pm\)100 mm with a measurement accuracy of 2 \(\upmu\)m. In the test, the sampling frequency of sensors was set as 1000 Hz.  
Two high-accuracy six-component force/torque balances (Gamma, ATI Company, Apex, NC, USA) were used to measure aerodynamic self-excited forces. The loading ranges of vertical force and torque were \(\pm\)65 N and \(\pm\)5 N\(\cdot\)m with high resolutions of 1/80 N and 1/1333 N-m, respectively. A sampling frequency of 1000 Hz was used to obtain the time-varied force/torque balances measured values.  
The two force/torque balances were installed between the sectional model and the springs on both sides of the model shown in Figure 3. The installation method was sturdy enough so that the mechanical damping of springs played a dominant role in the total damping of the whole dynamic system. Therefore, it should be reasonable to ignore the damping of the connection between the balances and the sectional model. The external forces acting on the sectional model included its own gravity, the supporting force from the force/torque balances, and aerodynamic self-excited force. For the sectional model during flutter, the dynamic equilibrium equation can be written as  
\[\left\{\begin{array}{l}F_{se}+F_{R}+F_{I}=0\\ T_{se}+T_{R}+T_{I}=0\end{array}\right. \tag{1}\]  
where \(F_{se}\) and \(T_{se}\) are the vertical and torsional aerodynamic self-excited forces, respectively; \(F_{R}\) and \(T_{R}\) are the vertical and torsional supporting forces from the force/torque balances, respectively, equating to the opposite measured values of two force/torque balances; \(F_{I}\) and \(T_{I}\) are the vertical and torsional inertial forces of the sectional model, respectively, and can be calculated by  
\[\left\{\begin{array}{l}F_{I}=-m_{sec}\ddot{h}\\ T_{I}=-I_{sec}\ddot{a}\end{array}\right. \tag{2}\]  
where \(m_{sec}\) and \(I_{sec}\) are the inertial mass and moment of the sectional model, respectively, and \(\ddot{h}\) and \(\ddot{a}\) are the vertical and torsional displacements of the sectional model, respectively. Therefore, the aerodynamic self-excited forces can be calculated as follows:  
\[\left\{\begin{array}{l}F_{se}=-F_{R}+m_{sec}\ddot{h}\\ T_{se}=-T_{R}+I_{sec}\ddot{a}\end{array}\right. \tag{3}\]  
Figure 3: Schematic diagram of self-excited force measurement; (**a**) snapshot of two six-axis force/torque transducers installation; and (**b**) dynamic balance principle.
# VDGA-Based Resistorless Mixed-Mode Universal Filter and Dual-Mode Quadrature Oscillator
## 5 Finite Tracking Error Analysis  
The finite tracking signal errors associated with the VDGA terminals may be taken into account in practical performance. By considering the parasitic transfer gains, we can describe the realistic VDGA using the following relationships:  
\[\begin{bmatrix}i_{z+}\\ i_{z-}\\ i_{x}\\ v_{w}\end{bmatrix}=\begin{bmatrix}\alpha_{A}g_{mA}&-\alpha_{A}g_{mA}&0\\ -\alpha_{A}g_{mA}&\alpha_{A}g_{mA}&0\\ 0&0&-\alpha_{B}g_{mB}\\ 0&0&\delta\eta\end{bmatrix}\begin{bmatrix}v_{p}\\ v_{n}\\ v_{z+}\end{bmatrix}. \tag{24}\]  
In this case, \(\alpha_{k}\) (\(\alpha_{k}=1-\varepsilon_{\alpha}\)) denotes the nonideal transconductance gain, while \(\delta\) (\(\delta=1-\varepsilon_{\delta}\)) indicates the nonideal voltage gain. Both deviate from their optimal values due to the transfer errors \(\varepsilon_{\alpha}\) ( \(\mid\varepsilon_{\alpha}\mid<<1\)) and \(\varepsilon_{\delta}\) ( \(\mid\varepsilon_{\delta}\mid<<1\)).  
The suggested resistorless mixed-mode universal biquad filter circuit depicted in Figure 2 is examined utilizing the nonideal model (24) of VDGA, resulting in the modified values \(\omega_{p}\) and \(Q\) as follows:  
\[\omega_{p}^{\prime}=\sqrt{\frac{\alpha_{A1}\alpha_{B1}g_{mA1}g_{mB1}}{C_{1}C _{2}}}, \tag{25}\]  
and  
\[Q^{\prime}=\left(\frac{g_{mC1}}{\delta_{1}\alpha_{B2}g_{mB2}}\right)\sqrt{ \frac{\alpha_{A1}\alpha_{B1}g_{mA1}C_{2}}{g_{mB1}C_{1}}}, \tag{26}\]  
where \(\alpha_{Ai}\), \(\alpha_{Bi}\), and \(\delta_{i}\) are the nonideal gains \(\alpha_{A}\), \(\alpha_{B}\), and \(\delta\) of the \(i\)-th VDGA (\(i=1\), \(2\)), respectively. From Equations (25) and (26), the various sensitivity coefficients with respect to active and passive elements are determined as:\[S_{\alpha_{A1},\alpha_{B1}}^{\omega^{\prime}_{p}}=S_{g_{mA1},\delta_{mB1}}^{\omega^ {\prime}_{p}}=\frac{1}{2},\ S_{C_{1},C_{2}}^{\omega^{\prime}_{p}}=-\frac{1}{2}, \tag{27}\]  
\[S_{\beta_{mC1}}^{\Omega^{\prime}}=-S_{\beta_{mB2}}^{Q^{\prime}}=1,\ S_{\delta_{1 }}^{Q^{\prime}}=S_{\delta_{2}}^{Q^{\prime}}=-1, \tag{28}\]  
and  
\[S_{\alpha_{A1},\alpha_{B1}}^{\Omega^{\prime}}=S_{g_{mA1}}^{\Omega^{\prime}}=- S_{\beta_{mB1}}^{Q^{\prime}}=\frac{1}{2},\ S_{C_{1}}^{Q^{\prime}}=-S_{C_{2}}^{Q^{ \prime}}=-\frac{1}{2}. \tag{29}\]  
Further, from Figure 3, the impact of the finite tracking signal errors on the OC and \(\omega_{osc}\) can then be obtained as:  
\[\alpha_{A1}S_{mA1}=\alpha_{B2}S_{mC2}, \tag{30}\]  
and  
\[\omega_{osc}=\sqrt{\frac{\alpha_{A1}\alpha_{B1}g_{mA1}g_{mB1}}{C_{1}C_{2}}}. \tag{31}\]  
From Equation (31), we find that the active and passive sensitivities of the \(\omega^{\prime}_{osc}\) for the proposed dual-mode QO circuit depicted in Figure 3 are identical to those expressed in Equation (27).
# Mechanical, Electrical and Fractural Characteristics of Carbon Nanomaterial-Added Cement Composites
###### Abstract  
This study investigates the effects of different carbon nanomaterials (CNMs), namely, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, and graphite nanoplatelets (GNP) on the mechanical, electrical, and fractural characteristics of cement composites. The electrical conductivity results indicated that CNT- and CNF-added composites exhibited percolation threshold ranges of 0.1% to 0.3% and 0.3% to 1.0%, respectively. Regarding the mechanical properties tests, the composite with a 1.0% CNF showed the best results. Furthermore, fractural characteristics results indicated that even additions of the smallest dosage, i.e., 0.1% of CNM, exhibited positive results. Overall, the study highlighted the potential of CNM-added cement composites.  
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