esa-sceva/satcom-chunk-collection huggingface dataset:
# Optimization and Application of Drilling Parameters Based on Gas-Solid Coupling Simulation
## 5 Engineering Practice
### Analysis of Pumping Effects and Technological Advantages
#### 5.2.2 Comparison of Technical Advantages  
(1) Deploying directional high-level long boreholes via directional drilling rigs to extract pressure-relief gas at the upper corner eliminates the risks associated with constructing high-level drainage galleries, such as accidental exposure to outburst-prone coal seams, faults, or aquifers during roadway development. This approach significantly enhances mine safety and ensures efficient production continuity.  
(2) Unlike fixed-location high-level drainage galleries, directional boreholes can be strategically positioned across different strata horizons based on site-specific geological conditions. This enables precision extraction of gas from multiple emission sources, effectively maintaining low gas concentrations in the upper corner, working face, and return airflow, thereby reducing drainage workload.  
(3) The adoption of directional high-level long boreholes significantly enhances operational productivity, with directional drilling rigs achieving a daily advance rate of 80-100 m, far exceeding the 5 m/day rate of conventional rock roadway development. This high-efficiency drilling method allows for parallel execution of gas drainage and roadway layout tasks, thereby substantially shortening project timelines. Additionally, the elimination of rock roadway excavation reduces associated infrastructure costs (e.g., pipelines, ventilation systems) and minimizes waste rock generation, lowering both haulage expenses to the surface and long-term maintenance demands, collectively yielding considerable economic advantages.  
(4) Directional boreholes minimize surface waste rock stockpiling, preventing environmental hazards such as spontaneous combustion of waste rock or contamination of soil and groundwater by sulfur-bearing toxic substances, thereby delivering substantial ecological and societal benefits.  
(5) By eliminating roadway development, waste rock haulage, conveyor system management, and long-term roadway maintenance, directional boreholes drastically lower operational and administrative costs compared to traditional gallery-based systems.  
According to Table 4, the use of directional high-level long boreholes instead of high-level drainage galleries for gas extraction can reduce the construction cost by 69.42%, reduce the amount of gangue by 2733.5 tons, and reduce the cost of gangue transportation by 218,680 CNY, and the construction period can be saved by 82.14%.
# Quantification of SPECT Concentric Ring Artifacts by Radiomics and Radial Features
## 3 Results
### Image Analysis Metrics  
The LASSO approach indicated that two radial features, \(R_{Contrast}\) and \(R_{RMSC}\), had high predictive performance, with 20 and 13 occurrences over the 30 iterations, respectively. \(R_{Contrast}\) and \(R_{RMSC}\) also showed significant rank correlation with the visual scores, with \(\rho\) = 0.66 (\(p\) < 0.001) and \(\rho\) = 0.65 (\(p\) < 0.001), respectively. The LASSO logistic model's performance in terms of mean AUC (an estimate of accuracy) was 80% (standard deviation = 16%). Concerning the \"equivocal\" readings (visual score = 2), two remained ambiguous, with 50% of iterations detecting the presence of ring artifacts, while the other 50% did not detect them. For the remaining artifacts, most of the iterations (>80%) agreed with the presence or absence of rings.
# On the Octonion Cross Wigner Distribution of 3-D Signals
## 1 Introduction
The above-cited application-oriented works are accompanied by a growing number of pure theoretical papers concerning octonion algebra [40; 41; 42; 43; 44; 45]. The octonion Fourier transformation concept has extensively been studied and developed in the papers of [PERSON] and [PERSON] [46; 47; 48; 49] where the basic properties of OFT were studied and proved, and continued in the works of other authors [40; 41; 42; 43; 44]. The door has been opened to successive generalizations in the field of octonion signal processing, particularly in the multidimensional hypercomplex discrete signal processing. One of the recent articles [50], for example, introduces the definition and presents a study of fundamental properties of the discrete OFT. This paper, devoted to the octonion Wigner distribution and the octonion ambiguity function, is an essential step towards the generalization of the concept of time-frequency analysis in terms of the hypercomplex Cayley-Dickson algebras. The article is organized as follows. We begin with recalling basic notation and facts concerning the octonion algebra and octonion Fourier transform in Section 2. The main part of this paper, Section 3, is devoted to the octonion Wigner distribution and its most important properties. In Section 4 we illustrate our results with some examples. Sections 5 and 6 provide comments and thoughts on how to extend OWD theory to other issues such as the octonion ambiguity function and the octonion Wigner-Ville distribution. We conclude with a short resume of the obtained results and our further research perspectives.
Analysis based on the assumption of random response or free response, commonly used in practical engineering, can be adopted. However, damage identification often requires a large number of iterative optimization searches which involve structural re-analysis including the repetitive assembly of the system parameter matrix and the calculation of structural modes. Obviously, it is time-consuming and inefficient in implementation to large-scale civil engineering structures. The VDM is a method for fast structural re-analysis. Its basic idea is that the response of a damaged structure can be modeled as a linear superposition of the original response of the undamaged structure (under the same external load) and the response to certain virtual distortions that are related to the damage [30]. Therefore, if the original response under external load is known, the response of the damaged structure can be quickly computed by applying virtual distortions. It is not necessary to rebuild the structural model and analyze anew the entire structure. [PERSON] et al. [31] reported on an application of the VDM in frequency domain analysis, and the effectiveness of the frequency-domain identification is demonstrated in numerical examples. [PERSON] et al. [32] calculated the response of a damaged structure in time domain by using the VDM, and then identified the damage and a moving mass excitation of the structure. Substructural analysis methods [33; 34; 35; 36; 37; 38] provide an effective way to reduce the number of considered structural parameters in damage identification of large-scale structures. [PERSON] and [PERSON] [39] divided a structure into several substructures, and proposeda SVDM to quickly construct the FRF of the damaged structure for identification of substructural damages. Here, a new computationally-efficient objective function is developed based on the SVDM for substructural damage identification using structural modal parameters. This paper is structured as follows: Firstly, traditional objective functions are introduced and briefly discussed; secondly, the improved objective function is proposed using certain characteristics of the peaks of the FRF. Finally, the accuracy and efficiency of the proposed method are verified by a numerical model of an eight-story frame structure.
# Smart Deployable Scissor Lift Brace to Mitigate Earthquake Risks of Soft-Story Buildings
## 4 Discussion
### Requirements for Practical Implementation  
1. Power supply--In the event of an earthquake, the electricity supply may be interrupted. To ensure the system's functionalities during and after an earthquake event, an uninterruptible power supply (UPS) must be installed.
2. The timing of deployment--the timing of the deployment of the structure and being able to securely anchor it to the main building is critical. There must be a sufficient time interval from the deployment of the structure to its secure attachment to the main building and the arrival of the earthquake. The deployable structure and actuators should be engineered to ensure optimal performance even in close proximity to the earthquake's epicenter, where the warning time may be very short.
3. Anchoring system--the anchoring system must be robust enough to firmly hold the deployed structure in place during an earthquake, preventing excessive acceleration of the roof that could lead to detrimental resonance throughout the system.
4. The obstruction of the deployable mechanism must be prevented during the normal usage of the ground level. The space required for the deployment needs to be fenced off from the occupants to prevent potential harm.
5. Earthquake signals and fail-safe design--as the system only relies upon the signals from the EEW system, there should be a substitute when the signal from the EEW system fails, such as onsite accelerometers or manual excitation. The other issue is sensitivity. High sensitivity may cause unnecessary triggering and the users may become troubled. There should be a fail-safe system developed to differentiate between an actual earthquake signal and a vibration due to the traffic or the wind.
6. Damping element--additional damping elements such as fluid dampers could be added to the proposed scissor lift mechanism to improve its vibrational control. However, this will result in the additional complexity of the anchorage design, which is envisaged to be further researched. Recent developments in self-centering devices [43; 44] may further enhance the system's performance and requires further research.
7. Cybersecurity--since the proposed system requires an internet connection between the EEW and the deployable structure, there may be network security issues. In future developments, encryption and decryption techniques could be used to ensure the correctness of the signals, or a separate network connection could be established between the building and the EEW system.
## 4 Experiments and Results
### Corneal Ulcer Segmentation Results
The coefficient of determination (r-squared) is calculated as 0.94. These results satisfy our expectations as to the accuracy and reliability of the proposed method. However, the experiment still provides some erroneous results. We highlight and analyze some of the inaccurately predicted outcomes, labeled as (a), (b), and (c), in Figures 15 and 16 to identify the causes of these inconsistencies. In these cases, significant errors in determining the percentage of the ulcerated area on the cornea arose from opposing errors in determining the cornea area and corneal ulcer area, explained as follows: in case (a), while the results from cornea segmentation are smaller than the actual cornea area, the outcome of corneal ulcer segmentation is larger than the actual corneal ulcer area; in case (b), the predicted cornea area is too large compared to the actual cornea \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Method** & **Accuracy** & **Micro DSC (\%)** & **Micro Sen (\%)** & **Micro IoU (\%)** & **MAE** \\ \hline U-Net & 99.24 & 88.15 & 87.56 & 78.88 & \(2.68\pm 5.23\) \\ U-Net-ResNet-50 & 98.95 & 82.68 & 77.82 & 70.48 & \(4.29\pm 9.89\) \\ U-Net with raw cornea mask & 99.32 & 89.22 & 86.91 & 80.54 & \(2.56\pm 5.09\) \\ Ensemble U-Net models with raw cornea mask & 99.32 & 88.96 & 85.12 & 80.11 & \(2.70\pm 5.28\) \\ Proposed method & 99.37 & 90.00 & 88.19 & 81.83 & \(2.51\pm 4.63\) \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Comparison of corneal ulcer segmentation performance across various methods. \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Method** & **Trainable Parameters** & **Maximum Memory Usage** & **Total Training Time** \\ \hline U-Net & 86,811,013 & 21.1 GB & 230 min \\ U-Net-ResNet-50 & 73,378,625 & 11.4 GB & 70 min \\ U-Net with raw cornea mask & 104,002,586 & 21.1 GB & 446 min \\ Ensemble U-Net models with raw cornea mask & 171,469,097 & 21.1 GB & 922 min \\ Proposed method & 171,469,097 & 21.1 GB & 788 min \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Comparison of resources and time required to create corneal ulcer segmentation models. area, but the predicted corneal ulcer area is slightly smaller than the actual corneal ulcer area; finally, in case (c), the results from cornea segmentation provide a moderately large area compared to the actual cornea area, but the outcome from corneal ulcer segmentation is considerably smaller than the actual corneal ulcer area.
## Appendix A Confidence Interval of the Error Rate  
In the last step of our experimental QBC protocol, [PERSON] is supposed to find \((1-\varepsilon)s\) photons detected by \(D_{b}\) instead of \(D_{b}\) when [PERSON] is honest. However, since \(\varepsilon\) is only the statistical average of the error rate of the experimental apparatus, [PERSON] cannot expect to find exactly \((1-\varepsilon)s\) photons detected correctly. A certain range of statistical deviations has to be allowed. Now, let us estimate the size of this range.  
According to Theorem 3.3 of ref. [2] (which is based on [PERSON]'s law of large numbers), when each of the \(s\) photons stands the probability \(p=(1-\varepsilon)\) to make the correct detector \(D_{b}\) click, for arbitrarily small positive value \(\delta\leq p(1-p)\), the probability for the case \(|s^{\prime}/s-p|\geq\delta\) to occur satisfies this equation:  
\[\Pr(\Big{|}\frac{s^{\prime}}{s}-p\Big{|}\geq\delta)\leq 2e^{-s\delta^{2}}. \tag{1}\]  
Here, \(s^{\prime}\) denotes the actual number of photons being detected correctly in a complete run of the protocol. This inequality means that \(s^{\prime}\) should be within the range \([(1-\varepsilon)s-\delta s,(1-\varepsilon)s+\delta s]\), albeit with a probability \(2e^{-s\delta^{2}}\) at the most. For example, when \(s=10\),\(000\), \(\varepsilon=10\%\), and \(\delta=5\%\), we have \(2e^{-s\delta^{2}}\simeq 2.8\times 10^{-11}\), which is extremely small. As a result, the number of photons that are actually detected by [PERSON]'s \(D_{b}\) should be within the range \([8500,9500]\), otherwise he can confidently conclude that [PERSON] is dishonest.
###### Abstract  
In order to solve the problem of low precision and efficiency in the balancing process due to the movement of balance counterweights in a built-in mechanical on-line dynamic balance system, an optimization strategy for the mass compensation of the mechanical on-line dynamic balancing system is proposed, and a mass compensation optimization model is established. The optimization model takes the phase of counterweight movement as the optimization variable and the residual stress under dynamic balance as the optimization objective. Through the optimization model, the movement phase of the counterweight can be calculated, and the counterweight can be moved to a balanced position that significantly reduces the degree of unbalance. An experiment platform was built to carry out comparison experiments under different rotating speeds and unbalance levels. By comparing the residual stress, amplitude, and dynamic balancing time of the spindle before and after the balance, the accuracy of the phase of the counterweight that is calculated by the optimization model is verified. The optimized dynamic balance compensation strategy and the unoptimized were compared by experiments at different rotating speeds. The experimental results showed that, compared to the unoptimized balance, the amplitude of the spindle after optimizing balance with a dynamic balancing device can decrease by 30.39% on average, with its maximum amplitude decreasing by up 50.18%, and the balancing time can decrease by 31.72% on average, with its maximum balancing time decreasing by up to 43.86%. The research results showed that an optimization strategy can effectively improve dynamic balance efficiency and greatly reduce vibration amplitude, which provides the necessary theoretical basis for improving the running precision of the spindle system.  
amss compensation; on-line dynamic balance; optimization strategy; unbalanced force
# Mini-Crack Detection of Conveyor Belt Based on Laser Excited Thermography
## 4 Experimental Setup, Procedure, Results, and Analysis
### Experimental Procedure  
As shows in Figure 9, a standard mini-crack of the conveyor belt is used to validate the feasibility and the practicability of the proposed method. Figure 9 is an optical picture with an actual size of 250 \(\times\) 150 mm\({}^{2}\). First, a Gagne mineral, whose density is 1.8 t/m\({}^{3}\), is fixed on the upper surface of the conveyor belt. Then, the conveyor is started, which cause friction between the gangue and conveyor belt to simulate the mini-crack generation  
Figure 8: (a) Laboratory test of belt conveyor; (b) The experimental platform of mini-crack detection system based on laser thermography.  
experiment. Finally, the image acquisition device is turned on to capture the thermal image of the conveyor belt.  
In order to verify the effectiveness of this method, three surface conditions of the conveyor belt, including the healthy case and the case with mini-cracks, were simulated in the experiment. The simulation experiment is based on COMSOL Multiphysics, which simulates the whole process of laser scanning conveyor belt. The length, width, and depth of the first mini-crack are 100, 1, and 5 mm, respectively; and the length, width and depth of the second mini-crack are 100, 5, and 10 mm, respectively. At the same time, we used COMSOL Multiphysics to simulate the thermal image changes of 100 mini-cracks with lengths ranging from 50 to 140 mm and widths ranging from 1 to 10 mm under laser excitation.
# Investigation of the Inverse Magnus Effect on a Rotating Sphere in Hypersonic Rarefied Flow
## 4 Results and Discussion
### Surface Quantities
#### 4.2.2 Distribution of Wall Pressure  
Figure 10 demonstrates the contours of \(C_{p}\) on the sphere. For the stationary sphere (Figure 10a), the distribution of wall pressure is axisymmetric. The high pressure is concentrated on the windward side, with the maximum pressure appearing at the leftmost pole of the sphere. The variation of pressure distribution with the rotation parameter is shown in Figure 10b-e. The distribution of wall pressure remains symmetric when the sphere rotates, in contrast to the velocity field shown in Figure 7. As \(W\) increases, the position of the maximum pressure stays unchanged, but the magnitude of \(C_{p}\) declines slightly.  
Figure 10: _Cont._  
Figure 9: Relation between (**a**) the skin friction distribution and (**b**) the relative velocity field on the sphere with rotation parameter \(W=0.5\).  
The wall pressure distribution makes a major contribution to the aerodynamic drag \(F_{x}\), but makes little contribution to the lift \(F_{y}\) (the inverse Magnus force). The roles of pressure distribution in the formation of lift are entirely different between rarefied flow and continuum flow.
## 3 Results
### Relationships between Oxidative Stress and the Apoptosis Process  
In the next stage, a correlation analysis showed a strong relationship between apoptosis and the cellular antioxidant system. In the fibroblasts co-exposed to fluoride and a SMF, the correlations between the genes that are associated with apoptosis and the genes that are associated with the antioxidant system were negative, which indicates that a restoration of the redox balance is accompanied by an inhibition of the apoptosis process (Table 3).  
In the next step, the relationships between the proteins encoded by the analysed genes were assessed using STRING analysis. The interaction network that was created (interaction score: high confidence \(-0.700\)) consisted of 17 nodes (proteins) and 47 edges (the expected number of edges was two). This showed that the predicted associations for an analysed group of proteins were statistically significant (enrichment \(p<0.001\)) and that these proteins, as a group, are connected biologically. Furthermore, this interaction network highlighted the fact that the protein that connects both processes, i.e., apoptosis and the cellular antioxidant system, is the Nrf2 transcription factor (NFE2L2) (Figure 2).  
Figure 1: Apoptosis in fibroblasts co-exposed to fluoride and a SMF at a different magnetic induction for 12 h (C—control cells; F—NaF-treated cells; F + SMF1—NaF-treated cells exposed to SMF at a 0.45 T flux density; F + SMF2—NaF-treated cells exposed to SMF at a 0.55 T flux density; F + SMF3—NaF-treated cells exposed to SMF at a 0.65 T flux density). The results are expressed as the means \(\pm\) SD, statistical significance: * \(p<0.05\) vs. C; # \(p<0.05\) vs. F; ~ \(p<0.05\) vs. F + SMF1).  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & **SOD1** & **SOD2** & **GSR** & **NFE2L2** & **CASP2** & **CASP9** & **TNF** & **TNF1** \\ \hline \multicolumn{1}{c}{_SOD1_} & & & & & & & \\ \hline \multicolumn{1}{c}{_SOD2_} & **0.72** & & & & & & \\ \hline \multicolumn{1}{c}{_GSR_} & 0.41 & 0.45 & & & & & \\ \hline \multicolumn{1}{c}{_NFE2L2_} & 0.02 & \(-0.38\) & \(-0.11\) & & & & & \\ \hline \multicolumn{1}{c}{_CASP2_} & \(-0.53\) & \(-0.36\) & \(\mathbf{-0.71}\) & 0.29 & & & & \\ \hline \multicolumn{1}{c}{_CASP9_} & \(-0.33\) & \(-0.08\) & \(\mathbf{-0.62}\) & \(-0.29\) & \(\mathbf{0.69}\) & & & \\ \hline \multicolumn{1}{c}{_TNF_} & 0.03 & \(-0.01\) & \(-0.58\) & \(-0.30\) & 0.51 & \(\mathbf{0.66}\) & \\ \hline \multicolumn{1}{c}{_TNFR1_} & \(-0.54\) & \(-0.45\) & \(\mathbf{-0.84}\) & 0.22 & \(\mathbf{0.89}\) & \(\mathbf{0.61}\) & 0.39 \\ \hline \multicolumn{1}{c}{All values in bold are significant \(p<0.05\).} & & & & & & \\ \end{tabular}
\end{table}
Table 3: Pearson correlation of the gene expression associated with apoptosis and the cellular antioxidant status in NaF-treated fibroblasts and co-exposed to a SMF for 12 h.
## 5 Simulation and Analysis
### Comparison of Running Time of Each Algorithm  
Table 3 summarizes the average runtime of a single Monte Carlo simulation for the six INCM reconstruction-based beamforming algorithms mentioned above. All simulations are conducted under the same conditions. Combining Tables 1 and 3, it is evident that, among these similarly performant beamforming algorithms, such as INCM-projection2 and INCM-volume, the algorithm proposed in this paper has lower complexity. Although the complexity of INCM-subspace and INCM-projection1 is lower, the proposed algorithm is easier to implement and has a better performance.
# Assessing Voltage Stability in Distribution Networks:
###### Abstract  
Distributed photovoltaic (PV) output exhibits strong stochasticity and weak adjustability. After being integrated with the network, its interaction with stochastic loads increases the difficulty of assessing the distribution network's static voltage stability (SVS). In response to this issue, this article presents a probabilistic assessment method for SVS in a distribution network with distributed PV that considers the bilateral uncertainties and correlations on the source and load sides. The probabilistic models for the uncertain variables are established, with the correlation between stochastic variables described using the Copula function. The three-point estimate method (3 PEM) based on the Nataf transformation is used to generate correlated samples. Continuous power flow (CPF) calculations are then performed on these samples to obtain the system's critical voltage stability state. The distribution curves of critical voltage and load margin index (LMI) are fitted using Cornish-Fisher series. Finally, the utility function is introduced to establish the degree of risk of voltage instability under different scenarios, and the SVS assessment of the distribution network is completed. The IEEE 33-node distribution system is utilized to test the method presented, and the results across various scenarios highlight the method's effectiveness.  
stochastic variable; correlation; voltage stability; probabilistic assessment Article  
A Methodology Considering Correlation among Stochastic Variables. _Applid_  
10.390/app1415645