esa-sceva/satcom-chunk-collection huggingface dataset:
# Adjustment Algorithm for Free Station Control Network of Ultra-Large Deepwater Jacket
## 3 Results and Discussion
### An Overview of the Control Network
#### 3.1.2 The Second Phase of Observation  
The second phase of observations was carried out in November 2023, and the monument of control point S2 was found to be damaged by the repeated rolling by large transport vehicles and heavy machinery during the construction of the jacket, so two new control points, S9 and S10, were added near it. By this time, the jacket had been constructed to a certain scale (as shown in Figure 4), and it was no longer possible to set up instruments in the center of the field, so a total of 12 stations were set up along the periphery of the field, as shown in Figure 5. The selection of the locations of these new stations was mainly based on the following considerations: firstly, they should be evenly distributed in the whole control network area; secondly, in the case of a serious line of sight occlusion, each station should be carefully selected to ensure visibility with at least three control points. In this way, reliable relatively geometric relationships between control points could be determined via adjustment by setting enough overlapping observations of common points between stations based on accurate angle and distance measurements obtained at each station.
## 3 Results  
### Study Selection  
The 33,531 studies were located in the database (including 21,265 from Scopus, 144 from PubMed, 71 from the Cochrane Library, 95 from ProQuest, 162 from Epistemonikos, 6714 from Science Direct, and 5080 from Springer Link). After the aforementioned criteria were added, 30,178 studies were eliminated because they contained duplicate entries, and 3353 studies were imported into the authors' library's Mendeley Group Reference Manager prior to the selection process. Automation tools removed 3161 studies from this process because they dealt with unrelated subjects. In the end, the authors manually screened 167 studies. Of the 142 studies, only 25 studies and their data were insufficient to address the research issue. Following a test of the full-text retrieval for the remaining 25 papers, 10 studies were eliminated since the whole text could not be retrieved. Following the completion of the full-text reading, the following studies were excluded: one for having the incorrect study design; four for having the incorrect result due to insufficient data on sensitivity and specificity; two for having the incorrect intervention; and one for having the incorrect comparator. As a result, only seven articles were thought to be eligible for acquisition. Figure 1 displays the PRISMA diagram flow chart that explains our research selection process. The eligibility of the seven included studies was assessed using the Cochrane ROBINS-E methodology. The evaluation bias check was passed by each of the seven listed studies from this approach. The PRISMA flowchart in research selection is shown below.  
Figure 1: Demonstrating study identification and selection. The initial database search identified 33,531 studies from seven databases (Scopus, PubMed, Cochrane Library, ProQuest, Epistemonikos, 1 Science Direct, and Springer Link). A total of 30,178 articles were excluded as they contained duplicate entries. After the selection process by the authors manually and automation tools, 3353 articles were eliminated. Eight articles were excluded for having an incorrect study design and did not contain appropriate outcomes, interventions, or comparators. The last step led to the inclusion of seven articles in the qualitative synthesis.
## 4 Conclusions  
In this work, we proposed a novel nanocomposite of antimony-germanate-borate SGB glass with functionalized optical properties given by an Ag\({}^{+}\)/Eu\({}^{3+}\) co-doping process. Due to the high thermal stability of fabricated glass, the glass fibers were produced so as to characterize the luminescence enhancement of Eu\({}^{3+}\) ions, as well as the self-assembling effect of silver nanoparticles on glass fibers surface. Firstly, a luminescent analysis showed an increase of \({}^{5}\)D\({}_{0}\)\(\rightarrow\)\({}^{7}\)F\({}_{2}\) transition intensity for SGB glass doped with 0.1 mol.% AgNO\({}_{3}\) directly after melting process. Moreover, the thermal treatment of this glass and glass fiber led to a further increase of emission at 616 nm by approx. 36 %. This indicates that in the SGB glass structure, the Ag\({}^{+}\) nanoparticles are created, and that surface plasmon resonance takes place. The second approach showed the non-conventional technology for the creation of silver nanoparticles on to glass fibers surface by a bottom-up process. This process was activated thermally without a reduction atmosphere, and strongly depends on Ag ion concentration. Ag\({}^{0}\) nanoparticles were obtained only in SGB glass fibers doped with 0.6 mol.% AgNO\({}_{3}\). Moreover, the nanoparticles were observed even before the additional heat-treatment. Thus, the optimization of the silver content allows the production of nanocomposite SGB glass fiber covered by a thin film of Ag\({}^{0}\) NPs directly, in a one-step method. It can be concluded that the proposed methodology for nanoparticle synthesis has potential applications in SERS substrates and biophotonic devices.  
[PERSON] conceived and designed the experiments, thermochemical reduction of silver nanoparticles; developed glass, and fabricated glass fiber; [PERSON], [PERSON] preformed the spectroscopic measurements, [PERSON] performed the DSC measurements; [PERSON] analyzed the data and wrote the paper.  
The project was funded by the National Science Centre (Poland) granted on the basis of the decision No. DEC-2016/21/D/ST7/03453.  
The authors declare no conflict of interest.
# Modeling and Analyzing a Multi-Objective Financial Planning Model Using Goal Programming
## 2 Materials and Methods  
### Goal Programming Problem (GPP)  
Several industrial problems have been solved in the last fifty years using Goal Programming techniques and Goal Programming models. The goal programming approach resolves multi-objective optimization problems by balancing conflicting objectives. In this process, the most effective indicator of goal achievement is determined. By using the goal-programming model, multiple and often incompatible goals can be accommodated.
## 3 Design Methodology of the Ideal Class-E PA with FDI
### Design Approaches
#### 3.1.2 Approach B: Design under an Optimization Goal  
In this approach, the Class-E PA is designed based on the same specifications of the approach A. However, we explore the overall PA design space in order to guarantee a high \(C_{p}\) according to circuit values of commercial components.  
Steps 1, 2, and 3: similar to the ones presented in Section 3.1.1. However, \(D\) and \(q\) are defined as design variables.  
Step 4: the design search space was plotted in Figure 8. The variable \(D\) should be less than 0.625 to accomplish the design restriction (i.e., \(V_{C_{SHm}}<30\) V), as shown in Figure 8a,b. An optimization process was developed over the search space of the components (Figures 8c-f in order to find circuit components under commercial values restriction. This process was implemented by parametric sweeps  
Figure 6: Waveforms of the Class-E PA designed in approach A. (**a**) \(v_{C_{SH}}\). (**b**) \(i_{S}\).  
Figure 7: Switching condition waveforms. (**a**) PA with ZVS and ZVDS. (**b**) PA without ZVS and ZVDS.  
of the \(D\) and \(q\) variables. We plot, in Figure 8g, the sweep of the optimum \(D\), from this family of curves we found the optimum value of \(q\) as 1.821.  
Step 5: following the process that is described in Section 3.1.1, we found the circuit components and its closest commercial values, as summarized in Table 5.  
Step 6: the design was verified by simulation, obtaining satisfactory waveforms for the approximate commercial values, as shown in Figure 9 (comm. sim.).  
Finally, Table 6 presents a comparison of the simulated results by following both design approaches with commercial components. The results are related to the electrical stress of the switch. The optimization process reduces the stress of the switch, in particular, the \(C_{p}\) was increased by 2079% approximately.
# Prototyping the Symmetry-Based Chaotic Communication System Using Microcontroller Unit
###### Abstract  
Chaos-based communications are a promising application of chaos theory and nonlinear dynamics. Their key features include concealed transmission, high security, and native broadband signals. Many studies have recently been published devoted to this technology. However, the practical implementations of chaos-based communications are rare due to multiple shortcomings: high hardware requirements, complex signal processing algorithms, and a lack of efficient modulation techniques for chaotic signals. In this study, we consider a simple hardware prototype of a coherent chaos-based communication system based on a novel type of modulation: adaptive symmetry of the finite-difference scheme used in a chaos generator. We explicitly demonstrate the possibility of covertly transmitting data using a chaotic transmitter and receiver implemented in a general-purpose microcontroller unit. A comparison between traditional parameter and symmetry modulation is given through a return map analysis and bit error rate estimation. The communication secrecy is analyzed using quantified return map analysis. The obtained results confirm the possibility of creating chaos-based communication systems based on symmetry modulation.  
chaos-based communication; covert transmission; secure communication systems; hardware chaos generators +
Footnote †: journal: Applied sciences
# Experimental Study on the Surface Properties of Nanoalumina-Filled Epoxy Resin Nanocomposites
## 3 Results and Discussion  
### Contact Angle  
The apparent CA, \(\theta^{*}\), was measured to evaluate the wettability of the EPNCs manufactured with a thermsetting epoxy resin hardened with two different curing agents and filled with different percentages of alumina NPs (1, 3, and 5 wt. (%)). The wettability is recognized satisfactory when the CA is less than 90\({}^{\circ}\)[38] (the solid surface is considered to be hydrophobic if the CA is above 90\({}^{\circ}\), and considered super-hydrophobic if the CA is above 120\({}^{\circ}\)), which means that the sample surface absorbs water. Figure 3 presents the obtained results for the apparent contact angle \(\theta^{*}\).  
Figure 3: Apparent contact angles of epoxy resin nanocomposites (EPNCs) using bis(4-aminophen)methane (DDM) and 3-dodec-2-enyloxolane-2,5-dione (DDSA) + 8-methyl-3a,4,7,7a-tetrahydro-4,7-methano-2-benzofuran-1,3-dione (MNA) as hardeners.  
From Figure 3, it is possible to observe that the control sample (CS) (neat EP) using DDM as hardener is super-hydrophobic and displays CAs of about \(123\pm 3^{\circ}\). With the inclusion of alumina NPs, the hydrophobicity decreases by around 9%, 20%, and 31% for 1, 3, and 5 wt. (%), respectively, when compared with CS. Additionally, for 1 and 3 wt. (%) samples, the EPNCs become hydrophobic, while for 5 wt. (%) it turns hydrophilic. The opposite trend is detected for samples with DDSA+MNA hardener. In fact, CS using DDSA+MNA is observed to be hydrophilic with a CA of around \(74\pm 3^{\circ}\), and a slight difference is observed with the inclusion of 1 wt. (%) alumina NPs. However, with further increase of the wt. (%) NPs, the wettability decreases and the EPNCs become hydrophobic, which is in accordance with the observation of [PERSON] et al. in 2019 [21]. From Figure 3, the major increase of about 53% compared with CS was observed for 3 wt. (%) alumina NPs. For 5 wt. (%) alumina NPs, the increase was about 40% when compared with CS. The decrease in the CA suggests that the wetting ability of the EPNCs increased [20]. According to [PERSON] et al. [1], better dispersion of NPs was achieved in the case of 1 wt. (%) NPs, while at 3 and 5 wt. (%), some NPs agglomerations were observed, which explains the increase of CA for such percentage loadings for the case with DDSA+MNA hardener. In fact, according to [PERSON] et al. [39], a higher NP concentration leads to a larger average particle size and induces higher CA. In the case of EPNCs with DDM as the hardener, better wetting ability was observed for 5 wt. (%), while in the case of EPNCs with DDSA+MNA, a smaller CA was observed for 1 wt. (%). When compared with CS, the EPNCs with DDSA+MNA containing 1 wt. (%) alumina NPs showed the better CA. The observed decrease in the contact angle for the case of the DDM hardener could due to the type of matrix thermsetting system used. This is in accordance with [PERSON] et al. [40], who stated that the hydrophobicity of the surface is influenced by the type of matrix and the composition of the filler constituent.
# Effect of Biochar Application Depth on Crop Productivity Under Tropical Rainfed Conditions
## 2 Materials and Methods
### Data Collection  
Data were collected for various growth and yield parameters of the Nerica-4 rice plant, including both belowground (root length and weight) and aboveground (shoot height and weight, tiller number, panicle length, and grain weight) parameters. All the variables were measured at hill-scale. Soil moisture was gravimetrically measured at harvest, with samples taken from 2 plots per treatment, except for the control treatment where 3 plots were used (Figure 2a).  
For crop height, measurements started at the end of the 4 th week (using a graduated PVC box pipe) and repeated every 2 weeks until harvest at the end of the 14 th week (which was on 4 th November 2016). Tiller number count started at the end of the 6 th week and also repeated every 2 weeks until harvest. With tillering, only the height of the tallest tiller in a hill was recorded. For the measurement involving weight, both fresh and dry weights were taken after harvest, although only dry weight was presented in this work. Again the data were taken at hill scale and since there was a large number of treatment hills (216 hills), samples were taken from the weighed fresh variables for dry weighing. The samples were tagged serially from 001 to 216, corresponding to the hill sequence in Figure 2a. The samples (of root, stem, panicle and grain) were again weighed fresh, oven-dried at 105 \({}^{\circ}\)C for 92 h (to a constant weight) and then reweighed to get the dry weight. Then the per-hill dry weight was calculated (by wet weight) from the sample as:  
\[V_{dwh}=\left(\frac{S_{dw}}{S_{fw}}\right)\times V_{fwh} \tag{1}\]  
where \(V_{dwh}\) is variable dry weight per hill [g]; \(S_{dw}\) is sample dry weight [g]; \(S_{fw}\) is sample fresh weight [g]; and \(V_{fwh}\) is variable fresh weight per hill [g].
# Photovoltaics on Landmark Buildings with Distinctive Geometries
## 3 Presentation of the Samples
### Copenhagen International School  
The Copenhagen International School, opened in 2017, is designed by the Danish office of C.F. Moller Architects and is located in Copenhagen outer harbour (Figure 14), Denmark (DK).  
Some architectural critics regard this awarded building (2017 Iconic Award) as unprecedented architecture of willingness and foresight [54]. It is famous by its tiled sea green solar facade, distinguishing this large structure from its neighbour buildings and connecting it with the surrounding ocean. The facade exposes the building as a leader in sustainable design. In general, the building is a result of the synergic activity of a motivated client, well technically equipped architectural office and an international community of researchers and manufacturers. Geometrically the building of the Copenhagen International School is cubical, with a BIPV facade consisting of approximately 12,000 PV tiles of \(700\times 700\) mm each, completely covering the object. With its more than 6000 m\({}^{2}\) solar tiles, and an installed capacity of 720 kWp [55], it is considered one of the largest BIPV plants in Denmark. It is expected to produce 300 MWh of electricity per year, more than half of the School's energy demand. The technology of the glass panels, developed at Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland [23], allows it to take one single colour with no need to apply pigments, thus decreasing panel efficiency. Having a possibility to choose between brick red, royal blue, golden yellow and sea green, the architects chose the sea green solution for the Copenhagen International School. The facade appearance is characterised by a stunning sequent-like effect, thanks to the 5\({}^{\circ}\) tilt angle of PV modules on four different orientations. This makes an effect of various colour hues, while in fact, all the PV  
Figure 13: Novartis Campus (top view of the building. Source of illustration Google Earth, Google 2020) **(on the top left)**. Integration and characteristic of PV systems **(on the bottom)**.  
modules are of the exact same colour. With introducing the described solar facade, the aim of the architects was not only to contribute to the production of green energy, but also to offer a facility in which students could learn about the environment as well as global research and production activity. Equipped with LCD screens showing the energy production to the students, the building has a strong pedagogical impact. Details regarding the total number and type of PV modules, their installed capacity and annual electricity production, where available, related to the aforementioned presented landmark buildings, are summarized in Table 2.
## 3 Results and Discussion
### Parametric Study
#### 3.3.2 Effect of Friction Angles of Solidified Soil  
Figure 8 shows the effects of the friction angles of solidified soil on the total settlements, vertical stresses and axial force of solidified soil embankments. The total settlements of solidified soil embankment slightly decreased with the increase of the friction angle of solidified soil in Figure 8a. The total settlements of different friction angles of solidified soil embankment were still small compared to the total settlement in gravel embankment. In Figure 8b, the vertical stresses of the solidified soil embankment exhibited little change  
Figure 6: The axial force along the depth of pile for different embankment materials.  
across different friction angles. Figure 8c,d show that as the friction angle increased, the total settlements along AB and AC slightly decreased, while the total settlements within the pile cap remained relatively unchanged. The axial force of the pile body slightly increased with increasing friction angles in Figure 8e. The effect of friction angles on total settlements is insignificant in solidified soil embankment. [PERSON] et al. [39] pointed that the friction angle of the gravel embankment fill has a negligible effect on the formation and characteristics of the soil arching.
# Robust IoT Activity Recognition via Stochastic and Deep Learning
## 4 Statistical Analysis and Feature Extraction
### Characterizing Sensor Data with Probability Density Functions and Statistical Moments  
Sensor data from accelerometers and gyroscopes are inherently time series data and can be modeled as stochastic processes. Our analysis begins by computing the probability density functions (PDFs) of these signals to reveal their underlying distributions. For instance, by examining the PDFs of accelerometer data along the x, y, and z axes during walking, several key characteristics emerge:  
* Multimodality: The PDFs exhibit multiple peaks, suggesting that the acceleration data do not fluctuate around a single value. This behavior reflects the periodic motion of different body parts (e.g., arm swinging and stepping).
* Symmetry and Skewness: While the distributions along the x and z axes are relatively symmetric, the y axis shows slight skewness, possibly due to natural body inclinations or specific gait patterns.
* Range of Fluctuation and Central Tendency: Differences in the spread of data across axes indicate that certain directions (e.g., the x axis) experience more pronounced acceleration changes, whereas others (e.g., the z axis) remain more stable.  
Similarly, the PDFs of gyroscope data, which capture angular velocities, offer insight into rotational dynamics:  
* Central Focus: All axes typically peak near zero, suggesting that rotational movements are minor and centered around a stable state.
* Data Concentration: The x and z axes exhibit sharper peaks compared to the more dispersed y axis, indicating differences in the stability of rotational motion.
* Subtle Skewness: Minor asymmetries in the distribution may be attributed to natural variations in walking dynamics.  
Our sensitivity analysis demonstrates that these distributional characteristics are significantly influenced by preprocessing techniques. The optimized Kalman filter (\(Q=10^{-5}\), \(R=10^{-2}\)) preserves the essential multimodal structure of activity-specific PDFs while reducing spurious peaks caused by sensor noise. This preservation of signal characteristics, while minimizing noise, contributes directly to the superior performance of statistical feature-based classifiers, particularly Random Forest models, which achieved 98.91% accuracy by effectively leveraging these distinctive distributional patterns.  
The figures below (i.e., Figures 3-5) illustrate the PDFs for accelerometer and gyroscope data during walking, running, and squatting, highlighting the distinct statistical characteristics of each activity.  
In addition to PDFs, first- and second-order statistical quantities such as the mean and variance provide fundamental information about the central tendency and dispersion of sensor readings. For example, higher variance in accelerometer data during running compared to walking reflects more intense movement dynamics. Higher-order statistical quantities, including skewness and kurtosis, offer further insights into the shape of the data distribution, capturing subtle differences that are crucial for fine-grained motion analysis.
# Effects of Diagonal Friction Dampers on Behavior of a Building
## 2 Experimental Studies
### Experimental Setup  
In the first stage of the study, free vibration records from the experimental models were used to determine the building periods. These data were used to validate the numerical model created in Sap2000. A shaking table and a rope displacement sensor were used to record free vibration. The shaking table has six degrees of freedom and a load carrying capacity of 20 kN. The displacements in the floors as a result of free vibration were recorded using a rope position meter that can measure with 77 \(\upmu\)m precision. The model building was fixed to the shaking table (Figure 3).  
The experimental model without a damper was named \"Reference\". Fifteen different layout configurations were created with dampers in order to examine the effect on building behavior when the friction damper was placed on different floors. Five of them were used in the experimental study (Figure 4). In naming the configurations, the floor number of the dampers and the abbreviation \"FD\" for friction damper were used. For example, the configuration with a friction damper only on the 5 th floor was named 5-FD.  
Figure 3: Experimental setup and experimental model.  
Figure 2: Friction dampers (unit of measurement is mm).