esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Multivariate Statistical Techniques and Data Treatment
### Data Treatment and Multivariate Statistical Methods
#### 3.2.2 Discriminant Analysis  
DA was used for discriminating between and among groups by applying discriminating variables. These variables measure characteristics regarding which the groups are expected to differ [44]. DA applies a linear equation of a regression analysis on raw data with prior knowledge of membership of objects to particular clusters and provides statistical classification of samples, expressed in the following equation [43; 45]:  
\[\mathsf{f}(\mathrm{Gi})=\mathrm{Ki}+\sum_{i=1}^{n}(\mathrm{Wij}*\mathrm{Pij}) \tag{5}\]where Ki is a constant specific to each particular group, i is the number of groups (G), n is the number of parameters used in group classification, and Wij is the weight coefficient designated by DA for the specific parameter (Pij).  
Independent variables are entered into DA either all together or stepwise, using both backward and forward approaches. In the first approach of variable entry, the discriminant function is calculated by engaging all the independent variables at once. This approach is used when there are a limited number of independent variables in the interest of discovering how well certain variables perform as discriminants in the absence of others. The stepwise method, on the other hand, involves entering the independent variables into the discriminant function (DF) one at a time. This stepwise input is based on the fact that variables with relative importance to the cluster variables with greater discriminant weights were entered first [46].  
In this study, standard, forward, and backward stepwise approaches of DA were applied to each matrix of the primary data. In the forward stepwise mode, discriminant function analysis (DFA) variables were added stepwise until no significant change occurred, while in the backward stepwise mode, variables were removed starting from least significant until a significant change occurred. For this purpose, two groups obtained from CA were selected for spatial evaluations [35].
###### Abstract  
Flooding, one of the most destructive and recurrent natural catastrophes, causes severe loss of life and property. The destructive effect of floods has increased with climate change and unplanned urbanization. To prevent this devastation and find solutions to potential flooding, it is important to improve engineering, ecological, hydrological, and hydrogeological precautions, as well as potential flood simulations. Using hydraulic models to perform flood simulations is a common and successful approach globally. In this study, HEC-RAS (1D) was used to simulate three different flood scenarios on the Bogacay sub-basin in Antalya, the most important tourism destination of Turkiye. Flood scenarios were developed based on the data of the floods that occurred in the region in 2003 and 2006, with measured flow rates of 1899.9 m\({}^{3}\)/s and 1450 m\({}^{3}\)/s, respectively, and with the maximum flow rate (2408 m\({}^{3}\)/s) determined by the relevant ministry. Then, the landscape composition of the region at the sub-basin scale was determined and the impacts of flood scenarios on the landscape composition around the riverbed were evaluated. The results of the analysis show that the water height will increase, ranging from 1.4 m to 3.6 m, and the landscape composition of the region will be significantly affected by this increase in water height in the three different flood scenarios. Especially in the part where the river meets the sea, 580.74 ha of urban settlement is estimated to be damaged by flooding, according to the worst-case scenario. Finally, the study will guide decision-makers to take the necessary measures under the relevant scenarios.  
flood risk; HEC-RAS; landscape composition; flood scenario; Bogacay sub-basin
# Multipath Mitigation for BOC Signals Based on Prompt-Assisted-Offset Correlator
## 6 Conclusions  
This paper proposes a new multipath mitigation technique named PAOC for BOC signals. Theoretical analysis and experimental results demonstrate that the PAOC technique significantly improves multipath performance with small noise performance loss. Moreover, it is found that subcarrier and carrier multipath errors can affect each other due to the coupling effect between the PLL and the SPLL. Therefore, this paper proposes to apply the PAOC technique in both the PLL and the SPLL of the DBT loop to mitigate carrier and subcarrier multipath simultaneously. Compared with existing multipath mitigation methods for BOC signals based on the DBT loop, the proposed method has better carrier and subcarrier multipath performance.  
Conceptualization, methodology, software, data analysis, investigation, and original draft preparation, review and editing, Z.T.; methodology and manuscript review, X.C.; supervision, project administration, and funding acquisition, M.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Key R&D Program of China under Grant No. 2021 YFA0716603.  
**Data Availability Statement:** Not applicable.  
**Conflicts of Interest:** The authors declare no conflict of interest.
## 2 Design Method
Figure 2b displays the linear illuminance \(E_{R}(x)\), \(E_{L}(x)\), and \(E_{R}(x)+E_{L}(x)\) calculated for various values of the parameter \(k\), with the light source mounted on the left wall. Uniform illumination across the ceiling is achieved when these profiles are combined with their counterparts from the opposite wall. A profile that incorporates the most beneficial aspects of the distribution will be selected for further development to optimize the lighting design. As illustrated in Figure 2b, the logistic curves \(E_{L}(x)\) for \(k=1\) and \(k=2\) exceed the ceiling boundary, resulting in light spillage beyond the target area. Consequently, the configurations leading to such spillage have been excluded from further consideration. In the subsequent phase of the design, careful assessment is conducted to align the array of LED packages with the ideal luminous intensity curve concept, prioritizing compact source sizes throughout the collimation system design. The finite size of the LED's emissive surface in relation to the lens size introduces complexities in closely mirroring the ideal luminous intensity curve. Conventionally, LED packages exhibit a Lambertian angular distribution, typified by a circular form in 2D and a spherical form in 3D distribution plots. This inherent distribution diverges significantly from the ideal luminous intensity curve, thereby necessitating the incorporation of secondary optics to redistribute lighting effectively. A linear AL was designed using SolidWorks as the initial redistributive optic. The lens' outer shape has been crafted as a semicircle centered at the LED package, while the inner shape has been divided into two distinct parts: a non-converging circular arc and a strongly converging straight line, both of which are centered at the LED package. An additional TIR component is necessitated by the wide angle of the LED's Lambertian luminous intensity curve. This TIR part is designed not only to effectively utilize the entire LED light beam but also to minimize glare when illuminating the ceiling. The AL-TIR design was optimized using ray-tracing software, which was employed to simulate the luminous intensity curves and conduct comparisons with the theoretical ideal. The luminous intensity curves were plotted in rectangular coordinates, and the design iteration continued until the difference ratio in each angular region was reduced to a saturated change of about 15%. Upon finalizing the AL-TIR optics design combined with the LED array, the ceiling illumination uniformity was evaluated using lighting simulations. The Dialux software was chosen due to its capacity for simulating large rooms with multiple luminaires.
# Implementation of MS Circle Map in Digital Image Encryption
## 4 Conclusions  
This study proposed a novel image encryption algorithm based on the MS Circle Map, leveraging chaotic dynamics to enhance security. The motivation behind this work stems from the increasing need for robust digital image encryption techniques capable of resisting various attacks. The proposed algorithm effectively integrates the MS Circle Map as a keystream generator, ensuring high randomness and unpredictability in encryption.  
Experimental results demonstrate that the algorithm exhibits high key sensitivity, a large key space, and strong resistance to brute force, statistical, and differential attacks. Performance evaluation through entropy analysis, correlation coefficients, the NPCR, UACI, PSNR, and MSE confirms its ability to maintain encryption quality while ensuring secure decryption. These findings highlight the significance of the proposed approach in improving the security of digital image transmission and storage.  
However, this study has certain limitations. The computational complexity is O(n\({}^{2}\)), which may impact processing speed for large-scale images. Additionally, the algorithm has not been tested against noise attacks or known-plaintext attacks, which could be considered in future research. Potential follow-up studies could focus on optimizing execution time using parallel computing or GPU acceleration, extending the method to multi-channel image encryption, and testing its robustness under additional attack scenarios.
# Federated Learning-Based Service Caching in Multi-Access Edge Computing System
## 2 Related Work
### Distributed Service Caching  
Ref. [16] studied the performance optimization of a 3-layer MEC system, including users, access points, and a cloud server. The objective of the proposed approach was to reduce the delay in the system while considering the limitations imposed by the energy boundaries. The concurrent optimization of service caching and task offloading was defined as a nonlinear mixed-integer problem. The proposed model used Lyapunov optimization and Gibbs sampling techniques to enable access points to make optimal service caching decisions.  
The authors of [12] studied the service caching problem in pervasive edge computing systems. The long-term optimization problem was deconstructed into a series of online sub-problems and then presented as Markov approximation problems. In addition, a distributed Markov chain was established to determine the most suitable services. Dynamic storAge-Stable Service caching (DASS) was proposed to maximize system utility.  
Another study [15] was conducted to reduce the service latency of the MEC systems. This investigation included several service delays, including switching, serving, and offloading delays. An optimization problem was transformed into a Markov decision processand handled using the Deep Q Network algorithm. The proposed framework facilitated individual base stations to make independent decisions regarding service caching based on local conditions.  
The authors of [11] introduced online service caching algorithms that do not rely on any assumptions regarding the patterns of user requests. The system under consideration has three distinct levels: user, edge server, and distant cloud layers. In addition, when a user requested a service unavailable on the edge server, the query would be sent to the remote cloud, or the service would be downloaded.  
In systems using distributed cache replacement, MEC servers are able to make optimal decisions based on local information at each server. These solutions are typically complexly designed to address the limits imposed by data constraints and the dynamic nature of the MEC system [17]. This imposes significant pressure on MEC server resources and makes its practical implementation unfeasible [17; 18]. In contrast to the current distributed techniques, the proposed strategy enables MEC servers to make independent decisions by using local data at each server and aggregated global knowledge. The FL architecture enables each MEC server to acquire information from the entire network without the need to share the raw data [14]. By incorporating local and global data characteristics, MEC servers are capable of making independent cache decisions efficiently. In addition, the AAE model used has a notably less complex structure compared to the RL models. This not only diminishes the resources required, but also enhances the practical applicability and guarantees model convergence.
# Observational Analysis of Variation Characteristics of GPS-Based TEC Fluctuation over China
## 3 Results and Discussion
### Spatial Distribution Analysis of ROTI over China on 8 October 2003  
Based on the ROTI analysis over China during the occurrence of ionospheric scintillation on 8 October 2003, Figure 4 shows the spatial distribution of all IPP according to certain TEC fluctuation conditions along the propagating paths of all observed GPS signals from each site. To weaken the impact of the single-layer hypothesis on IPP as much as possible, a cut-off elevation angle of 30\({}^{\circ}\) is selected for IPP extraction in this section. As demonstrated in Figure 4, the spatial distribution of moderate or strong TEC fluctuations satisfying ROTI \(\geq\) 0.5 is mainly located south of Guangdong, and very few TEC fluctuations are observed in other regions. The above phenomenon might be  
Figure 3: The time series of ROTI and amplitude scintillation index \(S_{4}\) for all of the observed GPS satellites at the QION and FUKE sites (8 October 2003). The vertical axis is the sum of the ROTI or \(S_{4}\) value and the PRN number of the corresponding satellite. The PRN numbers of each subfigure are as follows: (**a**) 1, 9, 13, 17, 21, 29; (**b**) 2, 6, 10, 14, 18, 26, 30; (**c**) 3, 7, 11, 15, 27, 31; (**d**) 4, 8, 20, 24, 28.  
Figure 2: The time series of ROT for all of the observed GPS satellites at the QION site (8 October 2003). The vertical axis is the sum of the ROT value and PRN number of the corresponding satellite. The PRN numbers of each subfigure are as follows: (**a**) 1, 9, 13, 17, 21, 29; (**b**) 2, 6, 10, 14, 18, 26, 30; (**c**) 3, 7, 11, 15, 27, 31; (**d**) 4, 8, 20, 24, 28.  
closely related to the physical phenomena of irregular ionospheric activities, such as equatorial plasma bubbles induced by ionospheric scintillation, which might be affected by solar flares, geomagnetic storms, atmospheric waves and solar wind structures.
## 3 AMoGA-GIS
### The Proposed HGCVRPTW Model  
Traditional VRPTW models suffer from oversimplification regarding vehicle attributes, inadequate considerations for varying recipient delay tolerances, and a lack of comprehensive environmental sustainability considerations. Firstly, they oversimplify when considering vehicle attributes, neglecting the crucial heterogeneity in carrier vehicle attributes necessary for practical urban logistics. Secondly, these models inadequately account for the varying tolerance levels of recipients for delays, potentially resulting in a decrease in service quality. Lastly, disparate congestion levels in the urban environment raise concerns about carbon emissions, which are associated with different routes and emphasize the need for a more comprehensive approach to environmental sustainability.  
Therefore, we designed the HGCVRPTW problem to comprehensively address these issues. Compared to VRPTW, HGCVRPTW introduces two additional considerations in its evaluation criteria:  
(1) As the gap widens between the arrival times of vehicles and the expected times of customers, customer satisfaction gradually declines. The traditional time window concept fails to adequately address this issue, limiting itself to serving customers within specific time intervals and overlooking customer expectations regarding service timeliness and flexibility. Customer satisfaction is higher when services are provided on time or as per their expected times. However, any delay or advancement in service timing reduces customer satisfaction. This degradation in satisfaction with increasing disparities between arrival and expected times is not entirely captured by the classical time window concept. Hence, this paper introduces the concept of customer satisfaction, evaluated as follows:  
\[minimize{\sum\limits_{i=0}^{n}{z(|t_{i}-t_{i0}|)}} \tag{6}\]  
where \(t_{i}\) is denoted as the actual arrival time at location \(i\), and \(t_{i0}\) represents the ideal arrival time at location \(i\). The function \(z(\cdot)\) is used to convert the time difference into satisfaction in this context;  
(2) Minimizing carbon emission costs has become an increasingly crucial objective in vehicle routing. Optimizing routes and schedules can reduce vehicle travel distances and time, thereby decreasing fuel consumption and carbon emissions. By minimizing carbon emission costs, enterprises not only reduce their environmental impact but also enhance their social responsibility image. This objective aligns closely with the growing global emphasis on sustainability and environmentally friendly transportation.  
\[minimize-\sum\limits_{i=0}^{m}{p_{i}L_{m}} \tag{7}\]  
where \(p_{i}\) denotes the carbon emission for route \(I_{i}\)\(L_{i}\) represents the length of the route \(i\), and \(m\) is the total number of routes after allocation. Notice that carbon emission here is a generalized measure that can refer to CO\({}_{2}\), CO, or PM emissions. Our algorithm is adaptable to different emission standards, making it flexible for various scenarios.
###### Abstract  
Ultra-high density data storage has gained high significance given the increasing amounts of data; many technologies have been proposed to achieve a high density. Among them, bit-pattern media recording (BPMR) is a promising technology. In BPMR systems, data are stored on magnetic islands. Therefore, high densities can be achieved by reducing the distance between the magnetic islands. Because of the closeness between the magnetic islands, the readback signal is distorted by two-dimensional (2D) interference, which includes the intersymbol interference according to the down-track direction and the intertrack interference according to the cross-track direction. A simple and effective serial detection algorithm was recently proposed to mitigate the 2D interference. However, serial detection utilizes the hard output in inner detection, and this degrades the serial detection performance. To resolve this problem, a subsequent study used feedback to estimate the noise and used this noise signal to create a soft output for inner detection. Following up, in this paper we propose a model that utilizes a neural network for noise prediction. The proposed neural network-based model and the model with the feedback line were compared in terms of bit error rate (BER). The results show that the proposed model achieves a gain of approximately 1 dB at a BER of \(10^{-6}\).  
information storage; bit-patterned media recording; soft-output Viterbi algorithm; neural network; intersymbol interference +
Footnote †: journal: Applied Physics Letters
## 3 Concepts, Models and Technologies
### Fog Computing  
Fog computing facilitates the management of data consistency and access controls in scenarios where two or more small, independent, distributed cloud entities share resources including files, computational resources, commands and authentication or access to local data storage within each Fog node on Figure 2. The Fog architecture [5] represents a fully distributed, multi-tier cloud computing system integrating millions of devices and a large-scale network of interconnected distributed cloud data centers. This architecture is particularly well-suited for applications requiring low latency and real-time responsiveness, such as those involving IoT devices as presented in [2; 6].
# Utilisation of Mining Waste for Production of Ceramic Tiles
## 2 Materials and Methods  
### Characterisation of Raw Materials  
#### 2.1.1 Characteristics of Post-Flotation Waste  
Post-flotation waste from copper processing exhibits specific physicochemical properties that make it potentially suitable for ceramic applications. The analysis of the particle size distribution (Table 1) reveals that approximately 90% of the material consists of particles smaller than 0.06 mm, with only minimal amounts of coarser fractions (2.0% > 0.2 mm, 4.6% between 0.2 and 0.1 mm and 2.3% between 0.1 and 0.06 mm). This fine particle size distribution is particularly advantageous for ceramic production, as it eliminates the need for additional grinding operations, potentially reducing processing costs and energy consumption.  
The chemical analysis of post-flotation waste (Table 2) indicates a composition dominated by silica (60.0-63.0% SiO2), with significant amounts of calcium oxide (14.4-17.2% CaO) and magnesium oxide (5.1-6.9% MgO). The relatively low alumina content (3.9-4.9% Al2O3) suggests limited clay mineral content, which requires its combination with more plastic materials for ceramic applications. The presence of alkaline oxides (K2O: 1.1-1.5%; Na2O: 0.29-0.31%) can contribute to the formation of liquid phase during sintering, potentially benefiting the densification process. The low iron oxide content (0.55-0.65% Fe2O3) indicates a minimal influence on the final colour of the ceramic products.  
\begin{table}
\begin{tabular}{c c} \hline \multicolumn{2}{c}{**Grain Size**} \\ \hline
**Class [mm]** & **Content [\%]** \\ \hline \(>\)0.2 & 2.0 \\
0.2–0.1 & 4.6 \\
0.1–0.06 & 2.3 \\ \(<\)0.06 & 89.9 \\ \hline \end{tabular}
\end{table}
Table 1: Average grain size of flotation tailings deposited at the “Gilów” facility.
## 3 Results and Discussion
### Crystalline Cellulose Content  
Dietary fibers have a beneficial effect on the gastrointestinal system, and chia seeds are rich in dietary fibers [47]. Since cellulose presents one of the main components of dietary fibers, we investigated the effect of light on cellulose content in chia microgreens, considering that germination can impact dietary fiber depending on the germination time as well as plant species [48].  
The cellulose content in dark-grown chia microgreens and microgreens 24 h after light exposure did not show significant differences. On the other hand, a significant decrease in cellulose content was observed in microgreens 48 h after exposure to light (Table 1).  
The germination process tends to increase dietary fiber content in different plant species such as peas and amaranth, as well as others [49; 50; 51]. [PERSON] et al. [5] reported on lower dietary fiber content found in chia sprouts, suggesting that the synthesis of dietary fibers such as cellulose, hemicellulose, and pectin are much slower in comparison to other sprouts in particular growth conditions.  
Figure 3: Ascorbic acid (AA) content in dark-grown chia microgreens and microgreens after exposure to light for 24 and 48 h. Data represent mean values from three experiments with five replicates (n = 15). The error bars show standard deviation (SD). Different letters signify values that are statistically different at \(p\leq 0.05\) according to [PERSON]’s LSD test.  
It is known that dark-grown microgreens have a characteristic pale phenotype with excessive shoot elongation compared to microgreens growing in normal light conditions. Therefore, more cellulose content could be found in such etiolated shoots [52]. In our study, a decline of cellulose content in microgreens, 48 h after exposure to light, could be due to the reprogramming of metabolic pathways and redirection of developmental processes in pathways that are light-dependent, such as photosynthesis and sugar synthesis, [53] as well as general plant elongation rather than cellulose synthesis.