esa-sceva/satcom-chunk-collection huggingface dataset:
# Study on Load Transfer Mechanism of Pile-Supported Embankment Based on Response Surface Method
## 2 Numerical Simulation of Pile-Supported Embankments  
### Model Establishment and Parameter Selection  
As shown in Figure 1, the test section is located in the bridge-subgrade transition section of the Rongwu Expressway in the Xiongan New Area. The soft soil foundation was treated with a prestressed pipe pile composite foundation. The strength of the prestressed pipe pile concrete was C60, the pile length was 14 m, the pile diameter was 0.4 m, and the pile spacing was 2 m. The top of the pile was set with a C30 square-reinforced concrete pile cap of 1.0 m \(\times\) 1.0 m \(\times\) 0.3 m. The cushion thickness of the test section was 0.3 m; it was a geogrid-reinforced gravel cushion.  
The dimensions of the pile-supported embankment are shown in Figure 2. The width of the subgrade surface was 42 m, and the slope ratio was 1:1.5. The soft soil of the foundation was continuously distributed, with a depth of 30 m. The thickness of the cushion was 0.3 m, the height of the embankment was 5 m, and the embankment was filled in layers.  
In order to improve the calculation efficiency of the model, an elastic medium was used to replace the soft soil subgrade to reduce the calculation depth of the subgrade.  
Figure 1: Geographical location of the test site.  
Figure 2: Cross-section of geosynthetic-reinforced piled embankment.  
The properties of the embankment filler and the geogrid strength in the numerical simulation were consistent with the field test conditions. The Mohr-Coulomb model was adopted for embankment materials, and the linear elastic model was adopted for piles and reinforcements; the parameters are shown in Table 1. The material parameters of piles, reinforcements, cushions, and embankment fillers were derived from laboratory tests. The material parameters of the soft soil foundation were inversely deduced by finite element software according to the deformation of the subgrade in the field test. The interaction between the geogrid and embankment filler was simulated by normal hard contact and tangential \"penalty\" contact. The contact friction angle between the geogrid and embankment was the same as the internal friction angle of the embankment filler [26].
# Study of Sea Fog Environment Polarization Transmission Characteristics
## 6 Conclusions  
In this paper, firstly, the physical characteristics of sea fog are studied. Based on the basic principle of polarization transmission characteristics in a sea fog environment, a simulation model of polarization transmission characteristics in a sea fog environment was established, and the polarization transmission characteristics in different environments were tested. The established model is effective and accurate in different scattering states of sea fog. The results indicate that salt fog has a significant impact on the formation and distribution of sea fog in three salt fog and water fog environments with varying salt concentrations and that, for a given optical thickness, the polarization of polarized light transmission is greater in salt fog than in water fog. In the setting of sea fog, circularly polarized light induces rotational symmetry, which improves its polarization-maintaining properties, and the greater the penetrating impact, the longer the wavelength. With increasing optical thickness, the polarization-maintaining quality of 671 nm polarized light  
Figure 11: Simulation and experimental comparison of DOP changes in three bands when the incident light is 0-degree linearly polarized light: (**a**) simulation results and (**b**) experimental results.  
Figure 12: Simulation and experimental comparison of DOP changes in three bands when the incident light is left-handed circularly polarized light: (**a**) simulation results and (**b**) experimental results.  
improves, making it more appropriate for use in environments with sea fog. This study establishes a theoretical foundation for the transmission properties of polarized light in a multi-layer sea fog environment. However, the factors that affect the sea fog environment are not comprehensive in this paper, and temperature, non-uniform shape, and other factors can be added later.  
Data curation, K.L. and M.Z.; formal analysis, Y.S. and J.D.; funding acquisition, Q.F. and J.Z.; methodology, Q.F. and S.Z.; project administration, Q.F. and Y.L.; resources, Q.F. and K.L.; supervision, Q.F.; writing--original draft, K.L.; writing--review and editing, K.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Changchun University of Science and Technology, China. [PERSON], National Natural Science Foundation of China, grant number 61890963.  
Not applicable.  
The study did not report any data.  
The authors declare no conflict of interest.
## 7 Conclusions, Limitations, and Future Work  
### Conclusions  
This study conducted an in-depth investigation into the application of ITS-CAL, powered by large language models (LLMs), in programming education. Through a comprehensive analysis of the usage behavior, learning outcomes, and subjective experiences of students with varying knowledge levels, the findings demonstrate the significant potential of ITS-CAL in providing immediate feedback, enhancing learning motivation, and improving educational outcomes. Additionally, the study highlights the differences in functional needs and usage patterns across different student groups.  
Compared to previous research, this study underscores the innovative and practical value of ITS-CAL. While prior studies have primarily focused on the role of artificial intelligence as virtual teaching assistants or chatbots, they often overlooked the specific technical challenges students face in programming. By developing three auxiliary functions (Hint, Debug, and User-defined Question), ITS-CAL leverages the advanced language comprehension and generation capabilities of LLMs to provide enriched problem-solving support. Unlike traditional systems that offer single-level, fixed feedback, ITS-CAL introduces hierarchical feedback tailored to students' individual needs, marking a significant advancement.  
Past studies have noted limitations in chatbot responses, such as generalized feedback or insufficient guidance [15]. This study addresses these shortcomings through the design of ITS-CAL. For instance, the Debug function analyzes errors and provides example explanations, helping students develop a deeper understanding of the underlying issues. The Hint function avoids offering direct code solutions, instead encouraging guided problem solving, contrasting sharply with traditional chatbots that primarily deliver direct answers.  
Furthermore, this study identifies distinct usage patterns among students with different knowledge levels, offering new insights that build upon the gaps in prior research. High-knowledge students tend to use the Hint and User-defined Question functions moderately, enhancing their problem-solving abilities. In contrast, low-knowledge students rely heavily on the Hint function but exhibit limited improvement in learning outcomes, indicating a need for additional, targeted support for this group. These findings highlight the importance of designing adaptive support mechanisms to address diverse student needs, providing a strong empirical foundation for the future development of LLM-driven educational systems.  
The primary contribution of this study lies in the development of a programming learning system that combines the immediacy and flexibility of LLM technology with hierarchical feedback. The results demonstrate its potential to enhance students' learning outcomes and optimize their educational experiences. Moving forward, these findings offer valuable guidance for improving intelligent teaching systems and underscore the need for continued innovation in leveraging artificial intelligence to support diverse learning environments.
# RCA-PixelCNN: Residual Causal Attention PixelCNN for Pulsar Candidate Image Lossless Compression
## 2 Background  
The FAST telescope's search for pulsar signals generates a vast quantity of pulsar candidate images. Considering storage and network transmission requirements, it is highly necessary to explore the compression of these pulsar candidate images using AI technology. Current AI methods in image compression are advancing rapidly. The typical approach involves utilizing generative models to model data distributions, followed by entropy coding.  
The PixelCNN model, as an autoregressive model, maximizes the use of pixel dependencies. By leveraging contextual information from neighboring pixels to predict the current pixel's probability density distribution, it demonstrates outstanding performance in data modeling. This makes it an excellent choice for lossless compression. Given its capacity to capture intricate pixel relationships, PixelCNN presents an ideal option for compressing pulsar candidate images, particularly due to their substantial volume, from both storage and network transmission perspectives.  
The assumption for data compression is that there is redundancy in the data and correlation between the data. The density model for compression should be able to model the data distribution and capture correlation and obtain better log-likelihood results.
## 5 Conclusions  
In conclusion, we demonstrated that hybrid thin films based on PVDF polymer showed that similar \(\beta\)-phase content, flat characteristics, and mean thicknesses of approximately 80 nm can present very different local piezoelectric responses. Linear piezoelectric effects for both the neat PVDF films and the hybrid ones were observed. Surprisingly, the hybrid samples presenting a similar percentage of \(\beta\)-phase content compared to the neat PVDF films did not show a similar piezoelectric resonance, evidencing a local polarization disorder promoted by the presence of the nano-inclusions. This effect was visible even though the number of nanoparticles was extremely low (\(<\)1 wt%). We succeeded in partially recovering the nanoscale piezoelectric properties by uniformly dispersing the nanoparticles inside the polymer matrix. The functionalization of the nano-inclusions improved the piezoelectric coefficient of 10%. Typical piezoelectric coefficient values of 10 pm/V were measured for the neat PVDF films. The robustness of the polarized domains was demonstrated vs. time by PFM images obtained after several scans. Thus, hybrid interphase optimization opens a possible way for the control of piezoelectric losses in magnetoelectric polymer-based thin films.  
The following are available online at [[https://www.mdpi.com/article/10.3390/app12031589/s1](https://www.mdpi.com/article/10.3390/app12031589/s1)]([https://www.mdpi.com/article/10.3390/app12031589/s1](https://www.mdpi.com/article/10.3390/app12031589/s1)), Figure S1: SEM images; Figure S2: AFM images; Table S1: Elaboration characteristics of the studied samples; Figure S3: XRD spectra; Figure S4: Agglomerates _Image_] analysis; Figure S5: _Image_] processing and analysis of the SEM images.  
Conceptualization, S.M. and A.G.; formal analysis, H.T.T.N. and A.G.; investigation, H.T.T.N.; sample elaboration: A.N.N. and J.S.; writing--original draft preparation, S.M.; project administration, S.M. and A.G. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
H.T.T.N. thanks USPC IDEX Project \"ArchiMEdes\" for the PhD grant support. ANR (Agence Nationale de la Recherche) and CGI (Commissariat a 1\"Investissement d'Avenir) are gratefully acknowledged for their financial support of this work through Labex SEAM (Science and Engineering for Advanced Materials and Devices), ANR 11 LABX 086, and ANR 11 IDEX 05 02 5. A.N.N. is grateful to the Labex SEAM for the financial support during his master's fellowship at LSPM (CNRS 3407). The authors acknowledge the financial support from NFFA-Europe (Nanoscience Foundries and Fine Analysis) for the PFM and SEM measurements.  
The authors declare no conflict of interest.
# PrECast: An Efficient Crypto-Free Solution for Broadcast-Based Attacks in IPv4 Networks
###### Abstract  
Broadcasting is one of the essential features in the Internet Protocol Ver 4 (IPv4). Attackers often exploit this feature of the IP protocol to launch several attacks against a network or an individual host. Attackers may either be a part of a Local Area Network (LAN) or outside a LAN to launch these attacks. There are numerous papers available in the literature to solve problems resulting from IP broadcasting. However, all these solutions target a specific problem that results from IP broadcasting. Furthermore, these solutions use either a computationally-intensive cryptographic scheme, the a priori relation between the host and the network or a modified protocol stack at every host. In this paper, we provide a seamless and transparent solution to eliminate IP broadcasting and thus eliminate all problems related to IP broadcasting. Our proposed solution is crypto-free and does not need any modification to the protocol stack.  
IPv4; ARP-poison; IP-broadcasting; DDoS; DHCP-hijacking Article
## 5 Conclusions  
A complete ecosystem of models for the ns-3 simulator has been presented. The utility of the ecosystem has been shown by simulating a scenario that is part of a research project involving the unattended monitoring of an offshore fish farming facility. Moreover, since this platform enables the use of real meteorological data and marine conditions from the location of the installation, the simulations are accurate and provide useful data before deployment.  
As future work, new MAC protocols will be implemented, as well as routing protocols to support multi-hop UWSN. Moreover, since network alive time is a major concern, energy-neutral algorithms will be studied by implementing the cooperation of the energy-harvesting model with the wake-up modem and MAC models.
## 1 Introduction
### Islandic Electricity Storage  
[PERSON] and [PERSON] [23] conducted research on the topic of combining renewable energy sources with the generation of hydrogen and its usage using fuel cells on a Greek island. The paper discusses the comparison between a single storage system (PHS) and a hybrid storage system (HPHS) for fulfilling energy requirements on islands, with the HPHS showing lower loss of load probability values despite higher cost, conducted on the island of Fournoi Korseon in Greece. The study emphasizes the importance of utilizing wind potential and coupling with storage systems for energy security.  
[PERSON] et al. [24] conducted research on the possibility of installing energy storage systems on the island of Terceira, which is located in the Azores and belongs to Portugal. The authors claimed that the installed power on the island in 2012 was 75.1 MW, while the greatest energy demand in 2018 would be approximately 30 MW to 35 MW. This difference was due to the fact that the maximum electricity demand in 2018 would be much lower. They determined that the optimal size of an energy storage system for 2018 would be 8.1 MW, which would be produced by water turbines working in a static waterfall at 340 m with a water flow rate of 3 m\({}^{3}\)/s. They also investigated the similarities and differences between electric batteries and hydro pump storage. The cost of a hydro pump storage system with 8.1 MW was predicted to be 15.56 million EUR, whereas the cost of batteries was 28.27 million EUR.  
[PERSON] et al. [25] conducted research on the topic of the storage of surplus power generated by wind farms on the Greek island of Crete by using hydro pump storage devices. The writers discussed the \"Potamon\" dam, which is situated in the prefecture of Rethymno and has the potential to be utilized for the storage of extra power. They indicated that the optimal capacity of power-producing turbines should be 31 MW, and it is projected that the yearly produced energy would account for 2.0-2.2% of the island's annual consumption of electricity.  
The introduction of storage methods can also assist in issues arising from RES's increased penetration levels to a microgrid. [PERSON] et al. [26] optimized the installation of hybrid power plants through the development of the energy system of the island of Rhodes. The stochastic production of the WT installed on the island presented significant frequency fluctuations, resulting in enforced RES curtailment. The methodology proposed a WT-battery storage coupling, estimating a reduction in frequency fluctuations and a yearly cost reduction above 7.9 million EUR.
## 4 Active Antiresonance Assignment with No Additional Masses
### State-Feedback Approaches  
The most eminent researchers in the field of dynamic structural modification also studied the antiresonance assignment through active control and proposed some meaningful results for linear time-invariant systems. The equation of motion of the closed-loop state-feedback controlled system is:  
\[\left\{\begin{array}{c}\mathbf{M\ddot{q}}(t)+\mathbf{C\dot{q}}(t)+\mathbf{Kq }(t)=\mathbf{Bf}(t)+\mathbf{B_{C}u}(t)\\ \mathbf{u}(t)=-\left[\begin{array}{cc}\mathbf{F}&\mathbf{G}\end{array} \right]^{T}\left\{\begin{array}{c}\mathbf{\dot{q}}(t)\\ \mathbf{q}(t)\end{array}\right\}\end{array}\right.\quad, \tag{13}\]  
where \(\mathbf{u}(t)\in\mathbb{R}^{N_{c}}\) is the control force vector (with \(N_{C}\) denoting the number of independent control forces), \(\mathbf{B_{C}}\in\mathbb{R}^{N\times N_{c}}\) is the control force distribution matrix, and \(\mathbf{F},\mathbf{G}\in\mathbb{R}^{N\times N_{C}}\) are the gain matrices.  
Antiresonance assignment has been usually studied in the case of rank-one control, i.e., one independent control force is employed. The control and gain matrices \(\mathbf{B_{C}}\), \(\mathbf{F}\) and \(\mathbf{G}\) become vectors, denoted in the following parts of the paper respectively by \(\mathbf{b_{C}}\), \(\mathbf{f}\) and \(\mathbf{g}\), leading to the scalar control force:  
\[u(t)=-\mathbf{f}^{T}\mathbf{\dot{q}}(t)-\mathbf{g}^{T}\mathbf{q}(t) \tag{14}\]  
As in ATMDs, speed feedback emulates passive dampers, while position feedback emulates passive springs. The use of acceleration feedback is less adopted, mainly because  
Figure 6: A summary of the active antiresonance assignment methods with no additional masses.  
antiresonance frequency can be shifted either through position feedback or through acceleration feedback. Nonetheless, most of the methods proposed in the following can be extended to account for acceleration feedback too.
# Time-Optimal Trajectory Planning for Woodworking Manipulators Using an Improved PSO Algorithm
###### Abstract  
Woodworking manipulators are applied in wood processing to promote automatic levels in the wood industry. However, traditional trajectory planning results in low operational stability and inefficiency. Therefore, we propose a method combining 3-5-3 piecewise polynomial (composed of cubic and quintic polynomials) interpolation and an improved particle swarm optimization (PSO) algorithm to study trajectory planning and time optimization of woodworking manipulators. In trajectory planning, we conducted the kinematics analysis to determine the position information of joints at path points in joint space and used 3-5-3 piecewise polynomial interpolation to fit a point-to-point trajectory and ensure the stability. For trajectory time optimization, we propose an improved PSO that adapts multiple strategies and incorporates a golden sine optimization algorithm (Gold-SA). Therefore, the proposed improved PSO can be called Golds-PSO. Using benchmark functions, we compared Golds-PSO to four other types of PSO algorithms and Gold-SA to verify its effectiveness. Then, using Golds-PSO to optimize the running time of each joint, our results showed that Golds-PSO was superior to basic PSO and Gold-SA. The shortest running time obtained by using GoldS-PSO was 47.35% shorter than before optimization, 8.99% shorter than the basic PSO, and 6.23% shorter than the Gold-SA, which improved the running efficiency. Under optimal time for Golds-PSO, our simulation results showed that the displacement and velocity of each joint were continuous and smooth, and the acceleration was stable without sudden changes, proving the method's feasibility and superiority. This study can serve as the basis for the motion control system of woodworking manipulators and provide reference for agricultural and forestry engineering optimization problems.  
woodworking manipulator; time-optimal trajectory planning; 3-5-3 piecewise polynomial; PSO algorithm +
Footnote †: journal: Applied  
10.3390/app131810482
# Investigation of Electromagnetic Angle Sensor Integrated in FR4-Based Scanning Micromirror
###### Abstract  
This paper performs a detailed investigation on the electromagnetic angle sensor integrated in the flame retardant 4 (FR4)-based scanning micromirror. An accurate theoretical model is presented, especially considering the coupling effect between the driving and sensing coils. Experimental results agree well with the theoretical results, and show a sensitivity of \(55.0\,\mathrm{mV_{P}/^{\circ}}\) and a high signal-to-noise ratio (SNR) of 71.9 dB. Moreover, the linearity of the angle sensor can still reach 0.9995, though it is affected slightly by the coupling effect. Finally, the sensor's good feasibility for feedback control has been further verified through a simple closed-loop control circuit. The micromirror operated with closed-loop control possesses better long-term stability and temperature stability than that operated without closed-loop control.  
integrated angle sensor; electromagnetic; coupling effect; scanning micromirror; closed-loop control; flame retardant 4 (FR4) +
Footnote †: journal: Applied sciences