esa-sceva/satcom-chunk-collection huggingface dataset:
# Study on Load Transfer Mechanism of Pile-Supported Embankment Based on Response Surface Method
## 3 Analysis of the Numerical Simulation Results
### Single-Factor Test and Results Analysis
#### 3.1.5 Parameter Sensitivity Evaluation  
Sensitivity analysis can be used to determine the influence of each influencing factor on the pile-soil stress ratio and to determine the weight of each influencing factor. By changing the size of the influencing factors, the change rule of the evaluation index can be determined. The sensitivity coefficient, \(S_{AF}\), represents the sensitivity of the influencing factors to the evaluation indexes. The larger \(\mid S_{AF}\mid\) is, the more sensitive the evaluation index, \(A\), is to the influencing factor, \(F\). The calculation equation is as follows:  
\[S_{AF}=\sum_{i=1}^{n}\frac{\Delta A_{i}/A_{0}}{\Delta F_{i}/F_{0}} \tag{2}\]  
where \(\Delta F_{i}/F_{0}\) is the change rate of the influencing factors, %; \(\Delta F_{i}\): is the amount of change in the influencing factors; \(F_{0}\) represents the corresponding parameters in model 1; \(\Delta A_{i}/A_{0}\) is the corresponding change rate of the evaluation index, \(A\), when the influencing factor, \(F\), changes in \(\Delta F_{i}\); \(\Delta A_{i}\) is the amount of change in the evaluation index; and \(A_{0}\) is the value of the evaluation index in model 1.  
The evaluation range of each influencing factor was determined by the single-factor test, and the sensitivity coefficient of each influencing factor was calculated, as shown in Table 3. It can be seen that the pile-soil stress ratio is sensitive to the change in the internal friction angle and the elastic modulus of the embankment filling, followed by the cohesion. The geogrid strength had the lowest sensitivity due to its large evaluation range, i.e., when the variation range of the embankment filler properties is small, the pile-soil stress ratio will change significantly, while the pile-soil stress ratio will only be affected when the geogrid strength changes greatly. Therefore, it is suggested that, in the design of pile-supported embankments, in addition to the main design parameters, such as pile length, pile spacing, and grid strength, the influence of embankment filling properties on the load transfer should be considered.
## 2 Methodology
### Orbital Parameters
#### 2.1.1 Semi-Major Axis (\(a\))  
The semi-major axis is a measure of the size of the satellite's orbit. For elliptical orbits, it is defined as the distance from the center of the Earth to the point in the orbit where the satellite is farthest from the Earth, known as the apogee. However, the semi-major axis is the radius of the orbit for circular orbits. The semimajor axis is related to the orbital period of the satellite, with longer periods corresponding to larger semimajor axes [27].
## 4 Analysis of the Modulational Instability
### The Anomalous-Dispersion Regime
#### 4.1.2 The Role of the Coupling Coefficient  
Figure 3a shows the MI spectrum as a function of the normalized coupling coefficient in the ANLDC, i.e., \(\kappa\) in Equations (12) and (13). The limit case of zero coupling, i.e., the system with decoupled cores, is included too. It is seen that the dependence of the largest gain and MI bandwidth on \(\kappa\) is very weak.
## 4 Chemical Methods for Synthesis of Magnetic Ferrite Nanoparticles  
There are many ferrite nanoparticle formation methods; however, the chemical methods are the most reliable and suitable for large-scale synthesis. Moreover, these methods precisely control nanoparticles' shape, stability, size distribution, and surface modifications. The most popular chemical synthesis methods include coprecipitation, hydrothermal, polyol, sol-gel, thermal decomposition, microemulsion techniques, combustion, and sonochemical (Figure 3).  
The shape and morphology of magnetic ferrite nanoparticles can be tailored depending on their intended applications. As shown in Figure 4, these nanoparticles, in the form of nanorods and nanocubes, display distinct catalytic and adsorption characteristics due to the increased surface area. Nanostructure morphology enhances the adsorption of pollutants, while shape mainly influences catalytic reactions, facilitating the decomposition of harmful substances. Nanorods have a greater surface area for reactions, which could enhance efficiency in specific catalytic processes [46; 55; 122; 123; 124; 125; 126; 127; 128]. The magnetic properties of MFe\({}_{2}\)O\({}_{3}\) nanoparticles can be exploited to separate them from the water after treatment.  
Creating magnetic ferrite nanoparticle-based sorbents has proven highly efficient in separating heavy metals in aquatic systems. In this instance, [PERSON] et al. discussed in their chapter how these sorbents' expansive surface area and magnetic properties improve the adsorption of heavy metals and facilitate their easy separation from water using a magnetic field [129]. [PERSON] et al. presented a comprehensive study of wastewater and environmental treatment methods that use magnetic cobalt ferrite nanoparticles to extract heavy metals such as lead (Pb), cadmium (Cd), and arsenic (As) from contaminated water [22]. The spherical nanoparticles may be favored in applications that demand uniformity and ease of dispersion. They might also be preferred for applications requiring a consistent shape and straightforward dispersion [130]. The size of these nanoparticles significantly affects their efficiency in water treatment applications.
# Potential of a SAR Small-Satellite Constellation for Rapid Monitoring of Flood Extent
###### Abstract  
Constellations of small satellites equipped with synthetic aperture radar (SAR) payloads can realize observations in short time intervals independently from daylight and weather conditions and this technology is now in the early stages of development. This tool would greatly contribute to rapid flood monitoring, which is usually one of the main missions in upcoming plans, but few studies have focused on this potential application and a required observation performance for flood disaster monitoring has been unclear. In this study, we propose an unprecedented method for investigating how flood extents would be temporally and spatially observed with a SAR small-satellite constellation and for evaluating that observation performance via an original index. The virtual experiments of flood monitoring with designed constellations were conducted using two case studies of flood events in Japan. Experimental results showed that a SAR small-satellite constellation with sun-synchronous orbit at 570 km altitude, 30-km swath, 15-30\({}^{\circ}\) incidence angle, and 20 satellites can achieve 87% acquisition of cumulative flood extent in total observations. There is a difference between the results of observation performance in two cases because of each flood's characteristics and a SAR satellite's observation system, which implies the necessity of individual assessments for various types of rivers.  
flood monitoring; synthetic aperture radar; small satellite; satellite constellation; disaster management
# An Elliptical-Shaped Dual-Band UWB Notch Antenna for Wireless Applications
## 4 Discussion and Outcomes
### Outcome of Ultrawideband Notch Antenna
#### 4.2.4 Time-Domain Characteristics  
Figure 24 illustrates analysis in the time domain, which includes group delay, isolation characteristics, and the fidelity factor for the proposed antenna. As mentioned in Section 4.1.4, these studies are carried out similarly.  
Figure 25 shows a high delay at both notched frequencies (5.3 and 8.1 GHz), but the group delay for the face-to-face and side-to-side configurations is less than 1 ns at all other frequencies.  
Figure 26 exhibits the phase variation of the input impedance of the proposed UWB notch antenna. The phase fluctuation throughout the operating band is linear, with the exception of the notched band's center frequencies, which are around 5.3 and 8.1 GHz. This difference in phase versus frequency in the notched band verifies that the signal's frequency components have a delay at the notched frequencies.  
Figure 27 shows that the antenna has good isolation characteristics (S\({}_{21}<-20\) dB). The fidelity factor in frontal and lateral configurations is more than 99%, as shown in Figure 28. The greater value of the fidelity factor ensures that the transmitted and received pulses are identical.  
For dual-band-notched UWB applications, the time domain analysis of antenna parameters shows that the suggested antenna is a good contender.  
Figure 24: Time-domain analysis with orientations, viz., (**a**) frontal and (**b**) lateral.  
Figure 26: Phase response \(\mathbb{S}_{21}\) of the proposed UWB notch antenna.  
Figure 25: Group delay of proposed UWB notch antenna.
## 3 Results  
### Identification and Selection of Studies  
A total of 1959 original articles were retrieved (Web of Science: 1196; PubMed: 763), from which 738 duplicates were removed, resulting in 1221 unique records. Following title and abstract screening, 1045 articles were excluded for not meeting inclusion criterion five. The full text of the remaining 176 articles was reviewed, leading to the exclusion of 12, 112, and 21 articles based on exclusion criteria one, two, and four, respectively. Additionally, one study was excluded due to a low-quality rating according to the MINORS checklist. Consequently, 30 articles fulfilled all inclusion criteria and were incorporated into the final qualitative synthesis (see Figure 1).
# A Meta-Analysis on Dual Protocols for Chronic Stroke Motor Recovery: Robotic Training and tDCS
## 2 Materials and Methods
### Data Synthesis  
We conducted all meta-analysis procedures using the Comprehensive Meta-Analysis software (ver. 3.3, Englewood, NJ, USA). To quantify overall and individual effect sizes, we calculated the standardized mean difference (SMD) with 95% confidence intervals (CIs) [49]. The meta-analysis on upper limb motor function included 20 short-term effect comparisons and 10 long-term effect comparisons, whereas the analysis on lower limb motor function used 5 short-term effect comparisons and 4 long-term effect comparisons. Positive SMD values indicated greater positive effects on motor improvements in the augmented active tDCS and robotic training protocol groups than in the sham control groups. We conducted random-effects meta-analysis models to account for different participants, interventions, outcome measures, or statistical methods used in the individual included studies [49]. The level of heterogeneity was estimated by [PERSON] [PERSON]'s \(l^{2}\)[70]. Publication bias was assessed by two approaches: (a) comparing original and revised funnel plots after the trim-and-fill technique [71] and (b) [PERSON]'s regression test [72]. Finally, we performed two moderator variable analyses to determine whether treatment effects were different, according to (a) study designs: randomized controlled trials (RCT) versus crossover versus non-RCT; or (b) recovery phase post-stroke: subacute versus chronic versus subacute and chronic.
## 2 Classification of Electromagnetic Surfaces
### Isolated Scatterers and Isolated Apertures  
Surfaces can also be classified as isolated scatterers or isolated apertures according to their topological structures. Isolated-scatterer surfaces refers to planar arrays composed of separated scatterers, while isolated-aperture surfaces are ones consisting of periodically spaced apertures, as shown in Figure 5. The two surfaces shown in Figure 5 are complementary structures of each other, which are defined as two structures that can cover entire plane without any overlapping. Isolated-scatterer surfaces and isolated-aperture surfaces usually have quite different scattering properties. For example, isolated-scatterer FSS is utilized for designing spatial bandstop filters while isolated-aperture one has characteristic of bandpass [3]. There are also some surfaces that can be either isolated scatterers or isolated apertures, like a grating of parallel conducting wires, which depends on field propagation direction [7].  
Figure 4: Homogeneous effective and spatially dispersive surfaces.
# Hybrid Power System for the Range Extension of Security Robots: Prototyping Phase
## 3 Conversion to Plug-In Hybrid Structure
### Retrofitting  
The plug-in HPS is similar in nature to the powertrain in modern plug-in hybrid electric vehicles (PHEVs). More batteries are added, and they can be charged as much as necessary by plugging them into a wall outlet. Compared to hybrid electric vehicles, the ability to charge larger batteries in advance enables PHEVs to drive for a longer range purely on electric power. PHEVs usually operate in the charge-depleting (CD) mode at start-up, namely a battery-only mode or an all-electric mode. Then, they switch to the charge-sustaining (CS) mode, if the battery reaches the lower limit of its SOC, exhausting the vehicle's all-electric range.  
Likewise, the HPS prototype was retrofitted by upsizing the existing battery and adding an on-board charger (see Figure 3). The storable energy was increased by connecting more batteries in parallel, yielding a 7S12P configuration. The upper limit of the usable SOC range was broadened by plugging them into a power outlet through the charger. The lower limit of the usable SOC range was extended by resetting the output voltage of the existing DC/DC converter. In theory, the wider the usable SOC range is, the more extended hours of operation the security robot serves. Before testing the plug-in HPS prototype, a computer simulation was performed to predict the impact of these modifications on the operation hours.  
Figure 2: Results of unit tests performed to identify the transient behavior of the entire system and its components. (**a**) Voltage and (**b**) Power versus time.
# TARS: A Novel Mechanism for Truly Autonomous Resource Selection in LTE-V2V Mode 4
## 4 System Model Assumptions and Proposed Mechanism
### TARS Mechanism
#### 4.4.3 RB Reselection  
It is known from the standard that after the start of transmission, once the selection counter reaches zero, the reselection of resources must be performed with probability \((1-p)\), where the value of \(p\) is set between [0-0.8] [33]. This can cause unfair selection for dense networks. As an example, a vehicle with a lower value of \(p\) may cause some vehicles to wait for their turn for RB selection. The value of \(p\) should be inversely proportional to the network density and not set as a random value between [0-0.8].  
\[P_{r}=1-\left(\frac{\forall\,R_{x}\,\in\,R_{i}\mid R_{x}\geq\tau}{R_{i}}\right) \tag{11}\]  
where \(P_{r}\) is the probability of reselecting the same RB, \(\tau\) is the threshold, which is set to less than or equal to 20% as in the standard [33], and \(R_{x}\) is some RBs out of the total RBs (\(R_{i}\)). \(R_{x}\geq\tau\) means the set of \(R_{x}\) greater than or equal to 20% free. Figure 10(a),b shows the effect of using \(P_{r}\) for RB reselection.
# Improved Bootstrap Method Based on RBF Neural Network for Reliability Assessment
## 1 Introduction
The Weibull distribution has been demonstrated to effectively model lifetime distributions in several practical engineering problems based on failure data for mechanical components, electronic components, and biological tissues. It can also describe different types of failure rate distributions, ranging from exponential to Rayleigh distributions. Due to the well-characterized nature of the Weibull distribution, it is widely used and among the most successful life models [11]. There is an extensive literature on the applications and analytical methods of Weibull models, such as the recent studies by [PERSON] et al. [12], [PERSON] et al. [13], and [PERSON] et al. [14]. This paper proposes an improved bootstrap method using the radial basis neural network based on the research by [PERSON] et al. [10]. Particularly, the exponential function is used to modify the empirical distribution function, and a neighborhood function is introduced to widen the range of values of the expansion samples. Moreover, the confidence interval of the parameters of the Weibull life distribution is estimated using the bias correction method. Finally, the proposed method is validated using failure data obtained from CNC machine tools.
## 8 Navigation
### Localization  
The ability to define the rover position and orientation within the environment is fundamental for efficient navigation. Modern localization techniques such as GNSS (see Section 5.5) coupled with IMU are commonly used to ensure accurate localization. This is particularly important in precision agriculture, where the exact position of the rover directly impacts the effectiveness of operations such as seeding, fertilization, and irrigation. Localization is crucial when a UGV operates in the same environment as humans, where high levels of safety and efficiency are mandatory [92]. However, navigation in cluttered environments is challenging, particularly in GNSS-denied areas such as under a sub-canopy. In such scenarios, vision-based algorithms that use depth cameras or LiDAR sensors are preferred [93].
# Modification of Insulating Properties of Surfaces of Dielectric High-Voltage Devices Using Plasma
## 5 Methods of Adjusting the Electrical Strength of Dielectrics: Surface Strength
### Surface Treatment and Measuring Methodologies  
The test methodology and relevant parameters were verified as follows:  
1. In the first step, the proposed methodology was employed for measuring six samples, two without a surface treatment and four with the surface exposed, by an atmospheric plasma discharge. The treatment was performed on samples of both types of material, namely, epoxy resin-based and thermoplastics-based materials.
2. After verifying the parameters and repeatability of the discharge exposure, the procedure was conducted again, this time on 10 samples of each category.
3. Before and after exposing the sample surface to a plasma discharge, we measured and evaluated the residual surface electric charge \(\sigma\) [C/m\({}^{2}\)], surface resistance \(R_{\text{P}}\) [\(\Omega\)], and electric current passing through the sample \(I_{\text{s}}\) [uA].
4. The time dependence of the stability of the parameters \(R_{\text{P}}\) and \(I_{\text{s}}\) was tested, and the measurement according to point 2 was repeated at pre-defined time intervals \(T\), namely, 24 h, 48 h, 72 h, and from 120 h to 144 h after exposure to the plasma discharge.
5. The post-exposure samples were transported in a container with a defined material and surface conductivity, pre-determined dimensions, and material structure/composition. The surface electric charge was measured and adjusted to ensure minimum surface charging of the exposed sample during storage and transport to the measurement laboratory.  
Regarding the surface parameters of the samples after treatment, these were measured according to the above-mentioned procedure in the following manner:  
1. Measuring system calibration: device, probe, environment, unexposed sample.
2. Measurement and evaluation of the resistance \(R_{\text{c}}\) using a CA-6543 device, Chauvin Arnoux, France.
3. Simultaneous measurement of the electric current \(I_{\text{s}}\) using a Kethley probe EA10000, Keythley, Tectronix, USA.
4. Evaluation of the resistance \(R_{\text{v}}\), electric surface charge density \(\sigma\), and electric intensity \(E\) in exposed and non-exposed samples.
5. The entire procedure 1-4 was repeated for the interval \(T\), namely, 24 h, 48 h, 72 h and from 120 h to 144 h.
6. Evaluation of the measured data and graphic recording.  
The treatment methodology is shown in Figure 16.
# Application Study of Adaptive Tracking Algorithm in Active Noise Control System of Transformer
## 1 Introduction
Due to the ideal experimental conditions, the adverse effect of acoustic feedback and interference sources on the FxLMS algorithm is neglected. [PERSON] proposed an internal composite reference signal transformer ANC algorithm to reduce the impact of interference sources on the ANC system [8]. But, there are frequency and phase deviations between the synthetic reference signal and the actual noise source. Thus, the residual noise signal should be collected by the secondary sensor to amend the synthetic reference signal adaptively in the feedback branch. Actually, there are three problems limiting the algorithm in practical applications, the influence of the interference source noise, phase compensation problem of various frequencies noise of the transformer and the difficulty of building the transfer functions of the primary acoustic channel and the secondary acoustic channel. Although the noise reduction experiment is carried out in a substation, the noise reduction effect is only studied on single of 100 Hz, while the others are not explained. [PERSON] proposed an ANC algorithm, using a power supply signal as a reference signal to avoid the adverse influence of acoustic feedback [9]. However, it could not be applied in practical applications either, because the power signal is converted to radiated noise through the coupling transformation of several physical fields, and the mathematical model of the transformation is not built in the algorithm. [PERSON]. [10] [PERSON]. [11] [PERSON]. [12] proposed an active noise barrier system. There are also acoustic feedback and interference source noise problems. The purpose of this paper is to build an ANC system for practical substations, according to the noise characteristics of transformers and their radiated sound fields. There are three contributions in this paper. The first is that an adaptive tracking algorithm is proposed, which can eliminate the influence of acoustic feedback and interference source. The second is that an ANC system prototype is built and the noise reduction experiment is carried out in a substation. The third is that the noise reduction effect of the ANC system is analyzed. The paper is organized as follows. In Section 2, the characteristics of transformer noise and acoustic radiation field in substation are measured and analyzed. In Section 3, an adaptive tracking algorithm for transformer noise is proposed. In Section 4, the ANC system prototype is built and the physical noise reduction experiment is carried out in substation. In Section 5, the experimental results are given and the influence factors of noise reduction effect are analyzed.