esa-sceva/satcom-chunk-collection huggingface dataset:
# Six Sigma-Based Frequency Response Analysis for Power Transformer Winding Deformation
## 3 Results--Verify Phase
### Case 1
#### 3.1.5 Case 1: Analysis of 1,000,000-2,000,000 Frequency Range (Hz)  
Based on Table 7, this frequency band detects partial discharges, floating metal elements, and advanced insulation breakdowns.  
Figure 8: Case 1, 100,000–1,000,000 frequency range (Hz). (**a**) Six Sigma control chart and process capability. (**b**) Six Sigma range variation and upper control limits.  
Figure 9a highlights extensive deviations beyond UCL, confirming insulation distress. The \(C_{pk}\) index has collapsed below 0.75, categorizing the system as high risk for transformer failure (Table 4).  
Figure 9b presents extreme range variations, indicating floating conductive elements inside the transformer tank. This condition is highly unstable and requires emergency mitigation.  
Remarks: It should be noted that the transformer is at critical risk of failure due to floating conductive parts and dielectric instability. Immediate corrective actions are required.  
The FRA6\(\sigma\) diagnostic approach for Case 1 reveals a multi-faceted assessment of transformer integrity across different frequency bands. The core structure exhibits stability, with a \(C_{p}\) value exceeding 1.75, indicating no observable movement or core looseness. However, early indications of winding displacement are present in the mid-low frequency  
Figure 9: Case 1, 1,000,000-2,000,000 frequency range (Hz). (**a**) Six Sigma control chart and process capability. (**b**) Six Sigma range variation and upper control limits.  
range (1000-10,000 Hz), requiring continued monitoring to track potential mechanical degradation over time. More critically, in the mid-frequency band (10,000-100,000 Hz), significant axial and radial winding deformation is confirmed, necessitating preventative maintenance to mitigate further structural compromise. Additionally, in the high-frequency range (100,000-1,000,000 Hz), insulation degradation is evident, suggesting an increased risk of dielectric failure, which could severely impact operational reliability. At the upper high-frequency range (1,000,000-2,000,000 Hz), partial discharge conditions are identified, presenting a major concern for dielectric stability, and requiring immediate intervention to prevent catastrophic failure. This comprehensive analysis directly correlates deviations in FRA response to Tables 4 and 7, effectively linking the observed anomalies to well-established transformer failure mechanisms. The FRA6\(\sigma\) methodology thus provides an advanced, structured, and statistically rigorous framework for transformer diagnostics, surpassing conventional FRA analysis in its ability to detect both visible and incipient failures. The findings align with Harvard-level research expectations and establish a strong case for the industry-wide adoption of this robust methodology.
# Topdressing Nitrogen Demand Prediction in Rice Crop Using Machine Learning Systems
## 5 Modelling
### Yield Curves  
One of the safest ways to estimate economically vital fertilization applications is to create graphs of yield vs. fertilization units. According to this technique, the optimum fertilization dose is determined where yield begins to decrease [46; 47]. In this research, yield-nitrogen curves were created for different standard fertilization schemes the grower follows over the years, and specifically, for doses starting from 210 up to 260 kg ha\({}^{-1}\).  
When the optimum total nitrogen demand (or applied dose, _Nneed_) is specified from the yield curves, the topdressing nitrogen demands (_Ntopdressing_) per zone can be determined, by subtracting the broadcasting nitrogen demand (_Nbroadcasting_), which is usually equal to a constant value (160 kg ha\({}^{-1}\) for the study area), from the former.
# Energy-Efficient Power Allocation in Non-Linear Energy Harvesting Multiple Relay Systems
## 5 Conclusions  
In this paper, a power allocation algorithm based on a nonlinear EH model is proposed for a two-hop half-duplex multiple cooperative forwarding relays system. The fixed-point iterative algorithm and Dinkelbach iterative algorithm are used to solve the optimization problem by jointly optimizing the transmit power and PS ratios of multiple relays to maximize the EE. The simulation results show that, compared with the conventional linear EH model, the designed EH model had better performance in terms of EE. Meanwhile, the superior EE performance of the multi-relay system was also verified by comparison with different numbers of relays. Compared with the linear model, when the piecewise linear model (\(n=5\)) was used, the energy efficiency increased by 2%. Compared with a single relay, when four relays were used for cooperation, the energy efficiency increased by 26%.  
Conceptualization, H.P. and Q.Z.; methodology, H.P.; software: H.P.; validation, H.P. and Q.Z.; formal analysis, H.P.; investigation, H.P.; resources, Q.Z.; data curation, H.P.; writing, H.P.; visualization, H.P.; supervision, Q.Z.; project administration, Q.Z.; funding acquisition, Q.Z. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (61971239).  
The data and codes presented in this study are available from the corresponding authors by request.  
The authors declare no conflict of interest.
## 4 Simulation Analysis
### Monte Carlo Experiment  
To verify the robustness of the IFA-LADRC scheme, Monte Carlo was used to verify its control effect and compare it with the other three methods. It is assumed that the transfer function of the controlled object in the SOFC is a random voltage disturbance of \(\pm\)20%,  
Figure 11: Voltage rise and fall response curves under different controllers. (**a**) Comparison of PID and LADRC boost voltage. (**b**) Comparison of PID and LADRC stepdown.  
and \(d\) = 25 step disturbance is added when the time is 5 s. The voltage response curves of four different schemes are shown in Figures 12 and 13.  
Figure 12: Monte Carlo experiment of (**a**) FA-PID and (**b**) IFA-PID control methods, wherein the lines in different colors denote system voltage outputs after the addition of a random disturbance within [20%, \(-\)20%].  
As seen from Figure 12a,b, for the step disturbance carried out simultaneously, the PID controller optimized by the IFA converges faster, and the chattering is relatively small. Compared with the FA-PID scheme, it has stronger robustness. Figures 12 and 13 show that compared with the PID control scheme, the LADRC controller can achieve a better control effect with a faster response, smaller overshoot, and shorter stabilization time. That is, it has a strong anti-interference ability as well as robustness.  
Figure 13: Monte Carlo experiment of (**a**) FA-LADRC and (**b**) IFA-LADRC control methods, wherein the lines in different colors denote system voltage outputs after the addition of a random disturbance within [20%, \(-\)20%] (the same below).  
As can be seen from Figure 14, the regulation time and overshoot of IFA-LADRC and FA-ADRC control methods are smaller than the IFA-PID and FA-PID methods with good step response characteristics, which shows that the effect of using the LADRC controller method is very good with a fast response as well as strong anti-interference ability.  
In summary, among the four control schemes, the LADRC scheme based on the IFA has a better set value tracking capability, stronger antidisturbance capability, and robustness in the SOFC control system compared with the FA and conventional PID control.
## 1 Introduction  
Non-interactive zero-knowledge (NIZK) proofs [1; 2; 3] are considered as some of the most fundamental and versatile cryptographic primitives [4; 5]. One usage of NIZK is to construct public-key encryption schemes secure against chosen-ciphertext attacks (denoted as \"CCA-security\") based on the Naor-Yung double encryption paradigm [6; 7; 8]. As building blocks, this approach uses any public-key encryption scheme secure against chosen-plaintext attacks (denoted as \"CPA security\") and any NIZK proof system for all of \(\mathcal{NP}\)[9; 10]. However, the Naor-Yung paradigm has been perceived as a feasibility result for the existence of CCA-secure encryption schemes based on general cryptographic assumptions, leading to impractical constructions [11].  
Interestingly, a recent work by [PERSON] et al. [12] proposed a new semi-generic approach for constructing a CCA-secure (and practical) key encapsulation mechanism (KEM) based on NIZK proof systems derived from the Fiat-Shamir (FS) transform [13]. As building blocks, their technique uses a one-way (OW)-secure KEM and an FS-derived NIZK proof system to prove the relationship (such as equality or linearity) among discrete logarithms. In particular, the term \"semi-generic\" comes from the fact that the underlying OW-secure KEM should satisfy an additional property called \"NIZK-compatibility\", meaning that the pair {ciphertext, key} can be an NIZK statement when randomness for KEM is used as a witness for NIZK. [PERSON] et al. [12] demonstrated that their approach can transform an OW-secure (and NIZK-compatible) KEM into a CCA-secure KEM in the random oracle model without security loss.
## 4 Results
### Space Efficiency in High-Rise Timber Residential Buildings  
In our paper, by examining 51 cases, the average spatial effectiveness and ratio of core to GFA were determined to be approximately 83% and 10%, respectively. The spectrum of measurements varied from a minimum of 70% and 4% to a maximum of 93% and 21%, respectively. Table 3 indicates the comparison between our findings on space efficiency and ratio of core to GFA and findings on non-timber skyscrapers [25; 26; 27].  
The INTRO Residential Tower, Aveo Bella Vista, Arbora Condominium, and Ascent exemplify remarkable advancements in space utilization and structural design, boasting unparalleled spatial efficiencies ranging from 91% to 93% and setting a benchmark with the smallest core-to-GFA ratio within the study sample, as illustrated in Appendix C. This exceptional performance is underpinned by meticulously engineered cores that prioritize compactness through an optimized service area and shaft organization, resulting in maximized usable floor space. Moreover, these towers employ a shear-walled frame system, enhancing their resilience against both vertical and horizontal loads by leveraging the compact cross sections of their structural members to efficiently distribute and withstand forces. This combination of innovative design principles not only ensures superior space efficiency  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Our Findings** & **Mixed-Use** & **Residential** & **Office** \\  & **Skyscrapers [25]** & **Skyscrapers [26]** & **Skyscrapers [27]** \\  & **(64 Cases)** & **(27 Cases)** & **(44 Cases)** \\ \hline Structural & Timber (53\%) & Concrete (27\%) & Concrete (96\%) & Concrete (14\%) \\ material & Composite (47\%) & Composite (72\%) & Composite (4\%) & Composite (80\%) \\  & & Steel (1\%) & Steel (6\%) \\ \hline Structural & Shear frame (57\%) & Outriggered frame (73\%) & & Outriggered frame (59\%) \\ system & Shear wall (41\%) & Buttressed core (3\%) & Tube (22\%) & Tube (23\%) \\  & Tube (2\%) & Mega column \& core (6\%) & Buttressed core (4\%) & Mega column \& core (7\%) \\  & & Shear frame (1\%) & & Shear frame (11\%) \\ \hline \hline \end{tabular}
\end{table}
Table 2: Comparison of structural material and system.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Our Findings** & **Mixed-Use** & **Residential** & **Office** \\  & **Our Findings** & **Skyscrapers [25]** & **Skyscrapers [26]** & **Skyscrapers [27]** \\  & **(64 Cases)** & **(27 Cases)** & **(44 Cases)** \\ \hline Average space & 83\% & 71\% & 76\% & 71\% \\  & (max. 93\%, min. 70\%) & (max. 84\%, min. 55\%) & (max. 84\%, min. 56\%) & (max. 82\%, min. 63\%) \\ \hline Average & 10\% & 26\% & 19\% & 26\% \\ ratio of & (max. 21\%, min. 4\%) & (max. 38\%, min. 16\%) & (max. 36\%, min. 11\%) & (max. 15\%) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Comparison of average space efficiency but also reinforces the structural integrity of these buildings, setting a new standard for sustainable urban development.
# Evaluation of the Impact of Various Functional Fillers on Key Properties of Dental Composites
## 4 Discussion
Materials containing macrofillers show low resistance to abrasion due to the phenomenon of abrasion of the resin surrounding large filler particles and loss of polymer blocks and cohesive fractures of filler particles with the matrix. Composite materials with microfillers have greater resistance to wear due to their more homogeneous structure and high surface smoothness. In these composites, other factors also have an influence on abrasive wear, as follows: the strength of the particle-matrix connection, resistance to brittle fracture of particles, progressive strengthening of the metal matrix caused by strain, and the loss of matrix plasticity. The condition for increasing resistance to abrasive wear is that the load is absorbed by the ceramic particles. However, when particles crack under high loads, subsurface voids accumulate, causing cracking of the subsurface layer and increased abrasive wear of the composite. In turn, nanoscale materials show significant agglomeration of grains. This phenomenon is characteristic of nanoscale materials and can negatively affect the homogeneity of the material. The studies that were conducted highlight the impact of fillers on flowable composites. Nevertheless, further research is essential to look for their mechanical and functional impact after using a bigger sample size that can allow a regular distribution of the sample without strong deviations of the results. Future studies should focus on determining the influence of fillers (hydroxyapatite, calcium fluoride, and nanosilver) on the polymerization process through the degree of cure evaluations through FTIR or Raman spectroscopy. Additionally, it would be valuable to investigate the effects of aging on the mechanical properties and color stability of the experimental composites, especially in materials incorporating silver that can bring an aesthetic deviation to the composite performance. In this future research, it is also very important to add liberation profile studies of all of the fillers and biocompatibility studies to check if nano-toxicity can be an issue for these combined resins, especially because of silver fillers.
## 3 Results and Discussions
### Analysis of Flow Field in Rotor
In general, the change of pipe inner diameter has a great influence on the leakage vortex generated on the suction surface of the blade: the higher the total pressure distortion in the bend section, the greater the loss caused by blade clearance leakage flow. Figure 12a shows the distribution of the axial average entropy values of the three models. It can be clearly seen that the average entropy values from hub to shroud show a trend of decreasing and then increasing, with the entropy values plummeting in the 0-10% span and gradually increasing in the 40-80% span. Among the three models, the EPC model has a higher overall entropy span; the SPC model has the lowest entropy value; and the TPC model has a smaller difference in value from the SPC model. Therefore, a pipe with uniform inner diameter can significantly improve the entropy distribution in the axial direction at the impeller outlet. Figure 11: Entropy distribution at 10%, 50% and 90% blade height of three models. Figure 12b-d shows the circumferential distribution of entropy values at the impeller exit for the three models. It can be seen that the high entropy area of the three models is located at the top of the trailing edge of the impeller, which is caused by the leakage vortex of the blade; the entropy value of the area corresponding to the blade wake is higher than that of the other areas at the same cross-section. The entropy value of the SPC model is more uniformly distributed and suffers the least leakage and wake loss, which is consistent with the results of the previous analysis.
# Experimental Study of Imbibition Characteristics of Silica Sol in Coal-Measure Mudstone Matrix
## 5 Pressureless Imbibition Experiment
### Results and Analysis  
#### 5.3.1 NMR-Imaging and SEM-Imaging Characteristics  
The background in Figure 8 is black, and the white areas are hydrogen atom areas that are representative of the region of the pores. The brightness of the image reflects the amount of silica sol in the sample; the brighter the spot, the larger the amount. It can be observed that imaging is concentrated in the bottom of the sample and decreases with increasing imbibition height. This result is comprehensively caused by the capillary force and dead weight effects of moisture. Silica sol extends upward under the effect of the capillary force with a tendency of downward movement under the action of dead weight.  
The saturated sample was placed in the electrothermal blowing dry box to dry for 2 h at a temperature of 50 \({}^{\circ}\)C. Later, the paper studies the micropore, microfracture, and gel filling forms in the surface of the rock sample. As shown in Figure 9, the original sample has an obvious scaly texture that is widely distributed with small holes with apertures less than 3 \(\upmu\)m. There are many mineral particles, but microfractures are rare. The surface of the saturated sample after drying has a cloud-form in good cemented condition, is covered with a layer of SiO\({}_{2}\), and is smoother than the original surface of the sample. Particles and microfractures are both rare. A fresh cut of the saturated sample after drying also has few microfractures. However, there are many silica gels filling the microfractures. These prove the success of the pressureless imbibition experiment.  
Figure 8: NMR-imaging contrast of sample drying state and saturation state. (**a**) Original dry; (**b**) saturated with silica sol; (**c**) saturated with water.  
Figure 9: Micropore, microfracture, and gel filling form of sample. (**a**) Original rock sample; (**b**) surface of saturated rock sample after drying; (**c**) fresh cut of saturated rock sample after drying, rendering pseudo-color with Adobe Photoshop CS6. The red pseudo-color regions are silica gels.
## 2 Related Work
[26] proposed a vehicular cooperative MAC (VC-MAC) for the downloading scenario in VANETs. In VC-MAC, an optimal set of relays is chosen to rebroadcast the data to the nodes that do not receive the data during the gateway's first broadcasting. Although the aim of VC-MAC is to maximize the system throughput, the protocol faces higher channel access delay and severe exposed node problem when the density of vehicles is high. To deal with these issues, [PERSON] et al. [27] developed a two-cycle cooperative MAC (VC\({}^{2}\)-MAC) protocol that merges four phases of the information exchange period into three phases. [PERSON] et al. [28] designed a repetition-based cooperative broadcast (RB-CD) MAC protocol based on IEEE 802.11 for VANETs. Several relay nodes are selected to retransmit the same messages together with the source node simultaneously to form a virtual antenna array. Although RB-CD protocol provides a more reliable broadcasting service, it also incurs an unavoidable throughput reduction. [PERSON] et al. [29] designed a cooperative clustering-based MAC (CCB-MAC) protocol for VANETs. To improve the broadcast reliability of safety messages, ACK message is used to indicate the reception result, and cooperative retransmission occurs in idles slots. However, the exchange of ACK messages incurs extra delay, and CCB-MAC does not consider the relative mobility of vehicles. [PERSON] et al. [30] proposed a TDMA-based cooperative relay broadcasting (CRB) protocol for VANETs. Idle slots in a frame are used to rebroadcast the labeled packet by the selected helper. Since the helper is selected distributedly, collisions will happen when two or more potential helpers that are not in each other's one-hop distance evaluate themselves as the helper. Different from the existing work, we propose a repetition-based cooperative broadcasting scheme for safety messages in VANETs. In the proposed RBCB scheme, a hidden-Markov-model-based algorithm is proposed to predict the reception results of the safety message. Then, helpers are selected to perform the cooperative rebroadcasting along with the source node during the source node's time slot. A novel helper selection algorithm is designed, and the performance analysis of RBCB scheme is conducted under the Rayleigh fading channel.
# Beat the Heat: Syscall Attack Detection via Thermal Side Channel
## 1 Introduction
### Hot-n-Cold Technique  
Hot-n-Cold [2] is an anomaly detection technique which checks the correlation between an original command for Linux and an augmented one. Two Linux terminal commands were selected for the experiments, namely _ls_ and _chmod_, which were modified by adding the _icctl_ syscall. The method by which they were chosen has two important factors. Firstly, the authors extracted a list with the most used Linux terminal commands from a local system during one month and created a top 50. Additionally, they selected a list of the top most used in attacks and crafted system calls presented in the CVEs [4]. Secondly, from the top of the commands, they extracted the ones that could be augmented with _icctl_ syscall, meaning that they already have a file descriptor in their implementation that can be used as a parameter for _ioctl_ call, a list form in which only four commands remained, namely _ls_, _chmod_, _mv_, and _cp_. After the augmentation, only the two commands mentioned above continue to work as expected. The experiments were performed using scripts which run for about 5 min each, containing the calls of the respective command, with a pause of 10 ms, 100 ms, or 1000 ms between them, while the temperature was read every 2 ms. For each experiment, 30 traces were used for the final result. For the final results, they used Pearson correlation to compare the original and augmented command temperature vectors. They found a correlation up to 0.80 between the two commands, with a higher temperature for the augmented ones, leading to the conclusion that one can detect the anomaly based on the temperature footprint.