esa-sceva/satcom-chunk-collection huggingface dataset:
# Multi-Objective Real-Time Planning of Evacuation Routes for Underground Mine Fires
## 2 Related Works
### Optimal Emergency Escape Route Planning  
Many disaster evacuation scholars have studied the problem of underground disaster evacuation route planning. One of the most mainstream research methods is to use optimization ideas to model it as a shortest path problem or a maximum flow problem. [PERSON] et al. used VentSim software to simulate the mine ventilation system of a coal mine and used the software to predict the escape route [27]. [PERSON] et al. simulated an exogenous fire under a room-and-pillar coal mine based on VentSim software and used a lightweight network flow algorithm to compute the lowest-exposure as well as the shortest-path avoidance routes under the disaster [4]. [PERSON] et al. proposed a bi-objective optimization model with minimum rescue time and minimum hazard level for selecting emergency routes in underground mine fires [28]. In 2023, [PERSON] reviewed the problem of underground mine fires and emergency evacuation, and pointed out two research routes for this problem: the optimization method based on graph theory and the risk assessment method based on multi-agent modeling and computational fluid dynamics [29]. In more complexity multi-objective optimization problems, [PERSON] et al. proposed a collaborative aerodynamic approach, utilizing neural networks and particle swarm optimization to achieve both Pareto optimality and solution diversity, outperforming other leading algorithms on benchmark datasets [30]. However, due to the cost requirements of underground sensor placement, fire sensors are often not placed in each and every roadway underground. Therefore, the above studies are simulated in software, and path planning is performed by calculating the weights of each roadway in the ventilation network based on the simulated data. Using software simulation, especially CFD simulation, firstly, the type of combustible materials and the location of the fire need to be known in detail for modeling, and it is often not possible to measure and obtain real data when the disaster occurs. Secondly, underground fires develop rapidly, and CFD simulation requires a certain amount of calculation time, which is difficult to meet the needs of emergency rescue.
## 3 Results
### Pig Behaviors as Detected by Sensors
#### 3.3.2 Correlation Between Sensor Outputs and Pig Behaviors  
Although the sensor was not designed to distinctly identify different pig behaviors, correlation coefficient analysis demonstrated a clear relationship between sensor outputs and specific as well as combined pig behaviors (Table 3). Positive correlation coefficients (\(\rho\)) were observed for sensor outputs with behaviors such as sow eating, standing, drinking, and sitting across both heat stress and cooling treatment groups. These findings are logical because these activities involved substantial sow body movements, which the sensors were capable of detecting. In contrast, behaviors where sows remained more stationary, such as nursing and sleeping, showed negative correlations with sensor outputs. Interestingly, sow lying behavior, despite the sows being mostly stationary, still resulted in some sensor detection due to minor body movements.  
For piglets, while nursing behavior showed negligible correlation with sensor outputs, walking behavior displayed positive correlations. Piglet sleeping behavior, on the other hand, resulted in negative correlation coefficients.  
When examining the combined behaviors of sows and piglets (Table 3), pig-moving showed the highest positive correlation with sensor signals for both heat stress (\(\rho\) = 0.81) and cooling treatments (\(\rho\) = 0.74). Conversely, negative correlations indicated minimal pig movement. Sow on-body, which involves minimal pig movement, showed the most pronounced negative correlation coefficients (\(\rho\) = \(-\)0.77 for heat stress and \(\rho\) = \(-\)0.56 for cooling). The analysis of 24 h time-series graphs, which compared pig moving scores with sensor outputs, further highlighted these correlations (Figure 7). Linear regression analysis yielded R\({}^{2}\) values of 0.652 for heat stress pens and 0.553 for pens under cooling treatment, illustrating that the sensors were effective in detecting pig movement associated with different behaviors. These findings verify the sensor's ability to capture behavior-induced movements, demonstrating its potential as a valuable tool for monitoring pig behaviors, although it does so indirectly through movement detection.  
\begin{table}
\begin{tabular}{c c c} \hline \hline  & **Heat Stress** & **Cooling** \\ \hline Individual behavior & & \\ Sow eating & 0.61 & 0.37 \\ Sow standing & 0.47 & 0.41 \\ Sow drinking & 0.38 & 0.27 \\ Sow sitting & 0.31 & 0.23 \\ Sow lying & 0.53 & 0.49 \\ Sow nursing & \(-\)0.10 & \(-\)0.14 \\ Sow sleeping & \(-\)0.61 & \(-\)0.50 \\ Piglet nursing & 0.05 & 0.12 \\ Piglet sleeping & \(-\)0.42 & \(-\)0.34 \\ Piglet walking & 0.69 & 0.64 \\ Behavior combination & & \\ Sow on-feet & 0.77 & 0.59 \\ Sow on-body & \(-\)0.77 & \(-\)0.56 \\ Piglet moving & 0.47 & 0.38 \\ Pig moving & 0.81 & 0.74 \\ Pig moving and lying & 0.75 & 0.70 \\ Sow on-feet and lying & 0.77 & 0.61 \\ Sow and piglet sleeping & \(-\)0.59 & \(-\)0.47 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Correlation coefficient (\(\rho\)) between observed pig behaviors and sensor outputs.
## 4 Conclusions  
CF/EP and CNTs/CF/EP composites were prepared by solution blending. The flame retardancy and thermal stability of the composites were measured by cone calorimeter and thermogravimetric analyzer. The mechanical properties were tested by tensile and flexural tests. The results show that there is a synergistic effect between CNTs and CF, and the flame retardant enhancement and smoke suppression for EP composites are more obvious than that of CF/EP. Some findings are as follows:  
The heat release rate of F7N7 is the minimum, which is 34.65% less than that of EP and 12.12% less than that of F7. The peak rate of smoke production of F7N7 is the smallest. The total smoke production of F5N5 is the smallest which is 43.04% lower than EP. Mean carbon monoxide production of F5N10 is reduced the most which is decreased by 12.33% than EP.  
The initial decomposition temperature of F7N7 is about 14 \({}^{\circ}\)C higher than that of F7, and its temperature is not improved effectively compared with EP, but the mass loss at T\({}_{\rm max}\) is obviously reduced. The apparent activation energy of F7N7 is 2.7 kJ\(\cdot\)mol\({}^{-1}\) more than EP. Finally, the thermal stability of EP is associated with the ratio of CNTs to CF.  
The mechanical tests show that the mechanical properties are not affected while the flame retardancy is improved, and the CNTs and CF have a certain synergistic effect on the mechanical properties of the EP.  
Conceptualization, G.-q.C. and G.-q.Z.; Methodology, G.-q.C. and G.-q.Z.; Validation, G.-q.C., Y.G. and G.-q.Z.; Formal analysis, G.-q.C.; Investigation, G.-q.C.; Resources, G.-q.Z.; Data curation, G.-q.C., J.Z., S.G.; Writing--original draft preparation, G.-q.C.; Writing--review and editing, G.-q.C., G.-q.Z., Y.G., J.Z., S.G.; Supervision, G.-q.Z.; Project administration, G.-q.Z.; Funding acquisition, G.-q.Z. This work was supported by the National Key Research and Development Plan (Project No. 2016 YC0802900) and supported by the Future Scientists Program of \"Double First-Class\" of China University of Mining and Technology (Grant No. 2019 WLKXJ055). And the APC was funded by the National Key Research and Development Plan (Project No. 2016 YFC0802900).  
We acknowledge some experimental supports from [PERSON] of Shenyang aerospace university. Also [PERSON] and [PERSON] helped us a lot for our experiments and we thank them here.  
Figure 7: Mechanical Section of CNTs/CF/EP composites from SEM. (**a**) EP (**b**) CF/EP composites (c,d) CNTs/CF/EP composites [26].
## 2 Proposed Method
### Joint Detection and Classification Network
#### 2.2.2 Joint Loss Function  
The JDC model was optimized by minimizing a joint melody loss that combines the two loss functions from the main network and the auxiliary network, respectively, as illustrated in Figure 1c. We detected the singing voice using both networks. That is, we summed the 721 pitch predictions in the output of the main network, \(o_{m}\), and converted them to a single \"voice\" prediction. This resulted in the voice detection output from the main network, \(o_{mv}\). We then added this to the output of the auxiliary network, \(o_{v}\), to make a decision for voice detection as below:  
\[o_{sv}=o_{mv}+o_{v} \tag{3}\]Then, the loss function for voice detection was defined as the cross-entropy between the sum of the voice output and the ground truth \(\mathbf{v}_{gt}\):  
\[L_{voice}=CE(softmax(o_{sv}),\mathbf{v}_{gt}) \tag{4}\]  
Finally, the joint melody loss function was given by combining the loss function for voice detection (\(L_{voice}\)) and the loss function for pitch estimation (\(L_{pitch}\)):  
\[L_{joint}=L_{pitch}+\alpha L_{voice} \tag{5}\]  
where \(\alpha\) is a balancing weight, and we used \(\alpha=0.5\) in our experiment (In our initial experiment, we tried three different values of \(\alpha\) (0.1, 0.5, and 1) and achieved the best overall accuracy with 0.5 on the test datasets. Then, we fixed \(\alpha=0.5\) in the rest of the experiments. This might not be optimal, and selecting an optimal value could improve the result.).
# A Universal Low-Complexity Demapping Algorithm for Non-Uniform Constellations
## 1 Introduction
The QSR algorithm will introduce errors in LLR calculation because LLR is only related to the constellation point closest to the received symbol. The quadrant condensed search reduction (QCSR) algorithm proposed in [9] combines the CSR algorithm and the QSR algorithm, but the problem when creating the subset still exists. An improved algorithm is proposed in [10] to solve this problem, and its subset is determined according to the constellation points that may have the minimum EDs with the received symbol, but the algorithm needs to recalculate EDs when calculating the LLR of each bit. Moreover, the subsets in the above-mentioned algorithms are determined based on statistical results, which may be inaccurate. The virtual-point-searching-based (VPS), further-approximated VPS (FAVPS), and condensed VPS (CVPS) algorithms proposed in [11, 12] are not based on statistical results, and their subsets are determined in the polar coordinate system through projection operations, but these algorithms are only suitable for APSK-like 2D-NUCs designed for low and medium CRs. The lattice reduction algorithm proposed in [13] quantizes the 1D-NUC constellation points and received symbols into a lattice, and determines the subset according to the position of the received symbols. However, the lattice reduction algorithm is only suitable for specific 1D-NUCs, i.e., the distance between adjacent constellation points must be an integer multiple of the minimum distance. This paper proposes an improved low-complexity NUC demapping algorithm, i.e., subset condensed search reduction (SCSR) algorithm, which can greatly reduce the number of EDs that need to be calculated and compared during the demapping process. SCSR algorithm is suitable for 2D-NUCs and 1D-NUCs designed for all CRs. The subsets of 2D-NUC are determined according to the quadrant of the received symbol, and the subsets of 1D-NUC are determined according to the sign of the in-phase (I)/quadrature (Q) component of the received symbol. These subsets are not determined based on statistical results, and the algorithm establishes different subsets for ED calculation and comparison. The algorithm also utilizes the condensation characteristic of NUC to further reduce the number of constellation points contained in the subsets. The SCSR algorithm proposed in this paper is based on the NUCs in ATSC 3.0, but it is also applicable to other NUCs. Simulation results show that the SCSR algorithm can greatly reduce the demapping complexity of the Max-Log-MAP algorithm with negligible performance loss. The rest of this paper is organized as follows. Section 2 introduces the characteristics of NUC. Section 3 describes the Max-Log-MAP algorithm and analyzes its complexity. Section 4 proposes the SCSR algorithm. Section 5 analyzes the complexity and bit error rate (BER) performance of the SCSR algorithm. Finally, the conclusions of this paper are summarized in Section 6.
# A Wideband Eight-Port MIMO Antenna with Reduced Mutual Coupling for Future 5G mm-Wave Applications
## 3 Results and Discussions  
The recommended eight-element ring-shaped MIMO antenna is an extension of the dual-port antenna presented in Figure 3. The eight-port antenna was printed and developed to verify the simulated outcomes of the mentioned antenna. It was printed on Roger RT/duroid 5880 substrate. The front and back sides of the printed antenna are given in Figure 15.
# Vegetation Dynamics and Recovery Potential in Arid and Semi-Arid Northwest China
The arid and semi-arid regions in northwestern China were shaped by their unique geography and ecosystems These areas face ecological sensitivity and meteorological risks, particularly severe droughts due to complex geographic and climatic factors [29]. In recent years, there have been numerous studies on the vegetation restoration potential in northwest China. For example, [PERSON] [24] indicated that most vegetation-covered areas in the Hexi region experienced significant changes during the period of 2001-2017, revealing clear signs of regional vegetation deterioration. [PERSON] [30] detected a significant improvement in vegetation recovery due to the reversion of farmland to forests and grasslands in northwest China. Also, it was found that runoff rates from the forested land were positively related to erosive rainfall (i.e., rainfall when runoff generated) and varied with forest canopy coverage. [PERSON] [31] identified an overall upward trend in vegetation cover in northwest China from 1982 to 2008. According to [PERSON] [32], northwest China was shifting from a warm-dry to a warm-wet climate regime. The detrimental effects of this temperature increase have made climate change's impact on northwest China a topic of extensive research [33]. However, studies addressing the potential for vegetation restoration under climate warming and humidification are still relatively scarce, especially quantitative ones. In the past three decades, northwestern China has experienced consistent climatic warming and increased moisture levels. However, research on vegetation restoration potential in this region has been limited. Therefore, it is crucial to explore the potential for vegetative resurgence, particularly in arid and semi-arid regions, providing valuable insights for vegetation restoration efforts. This study seeks to shed light on the impact of these climatic changes on the recovery of native vegetation. Does the warmer and wetter climate facilitate or hinder vegetation restoration in northwestern China? Moreover, how do changes in vegetation distribution within the region respond to these alterations? This study is offers critical insights for ecological restoration, desertification control, and sustainable development. The findings underscore the importance of targeted ecological governance to address the challenges posed by environmental degradation in the arid and semi-arid areas of northwest China.
# Toward Questionnaire Complexity Reduction by Decreasing the Questions
## 3 Research Framework
### Context  
The University covered in this work delivers around 70 bachelor's degrees, 70 master's degrees, and 20 PhD programs from different branches of knowledge and more than 30,000 students. Due to this, a great heterogeneity is present in the degrees, courses, and academic years.  
In order to assess our proposed methodology, different subjects that belong to the Computer Sciences engineering branch were selected in different academic years. The considered subjects were the Computational Techniques in Software Engineering (CTSI) course and the Theory of Automata and Formal Languages (TAFL) course, both belonging to the Computer Sciences engineering branch. The information related to each course can be observed in Table 2 (CTSI year 21-22 data is not available). The aim of choosing these subjects is that the number of students it usually has enrolled each academic year allows us to extract more solid conclusions. It is important to highlight that early courses in a degree program are usually ignored because they may introduce a potential distortion in the outcomes as many students are still uncertain about the specific degree they wish to study. In this work, it was considered that a student is deemed to have not completed the CHAEA survey if that questionnaire has at least one or more unanswered questions.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Subject** & **Degree** & **Course** & **Year** & **Attd.** & **Resp.** & **Unc.** & **Rate** \\ \hline \multirow{4}{*}{CTSI} & \multirow{4}{*}{BSc in Software Engineering} & & 18–19 & 65 & 26 & 17 & 40.00\% \\  & & 19–20 & 73 & 42 & 8 & 57.53\% \\  & & 20–21 & 68 & 34 & 10 & 50.00\% \\  & & 22–23 & 76 & 17 & 7 & 22.36\% \\ \hline \multirow{4}{*}{TAFL} & \multirow{4}{*}{BSc in Computer Science} & & 18–19 & 157 & 50 & 9 & 31.85\% \\  & & 19–20 & 157 & 56 & 21 & 35.67\% \\ \cline{1-1}  & & 20–21 & 164 & 34 & 23 & 20.73\% \\ \cline{1-1}  & & 21–22 & 174 & 21 & 10 & 12.07\% \\ \cline{1-1}  & & 22–23 & 185 & 35 & 21 & 18.92\% \\ \hline \hline \end{tabular}
\end{table}
Table 2: Summary of the number of enrolled students (Attd.), the participants who completed the survey (Resp.), and the participants who did not complete the survey or just opened it (Unc.) among the selected courses.
## 2 Materials and Methods
### System Description
#### 2.3.4 Synchronization Method  
The research effectively utilized the chrony protocol and the DS3231 RTC module to establish highly accurate and synchronized time throughout the network. The configuration of the RPi4 gateway as a local NTP server, operating at stratum 1, allowed it to obtain precise UTC time from a reliable NTP server. Concurrently, all other RPi0-2W nodes in the network were appropriately configured as stratum 2 (by modifying chrony.conf [68]), enabling them to synchronize their time with the RPi4 gateway. Consequently, the RPi4 gateway served as a reliable source of synchronized time for all RPi0-2W nodes in the network. Moreover, the strategic utilization of the DS3231 RTC module as a redundant timekeeping mechanism ensured uninterrupted time synchronization across the network, particularly during instances of internet connectivity loss. Overall, these measures enhanced the precision and reliability of time synchronization within the network.
###### Abstract  
Deception jamming of synthetic aperture radar (SAR) has attracted extensive attention due to its low power consumption and high fidelity advantages. However, existing SAR deception jamming algorithms assume that SAR operates on a linear trajectory. In practice, SAR trajectories often become nonlinear due to factors such as atmospheric turbulence, which results in the jamming signals lacking the two-dimensional spatial variability of nonlinear-trajectory SAR echo signal and affects the imaging quality of deception jamming. This paper proposes a new algorithm for nonlinear-trajectory airborne SAR deception jamming based on hybrid domain efficient (HDE) modulation. This algorithm derives the jamming frequency response (JFR) with SAR trajectory deviation in the azimuth time-frequency hybrid domain. Based on the hybrid domain modulation, the jammer calculates the JFR of the linear trajectory in the azimuth frequency domain and constructs for the real-time trajectory deviation pulse by pulse at each azimuth moment. The real-time modulation process of the algorithm only involves range domain Fourier transform and complex multiplication, combining computational efficiency and modulation flexibility. The validity constraints of the algorithm have been analyzed to ensure the focusing ability of the jamming signal. Simulation and computational complexity analysis validate the excellent performance of the algorithm in imaging quality and efficiency.  
deceptive jamming; synthetic aperture radar; nonlinear-trajectory; hybrid domain modulation 2023  
1 Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China 1  
[PERSON]  
1 Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China 12 Key Laboratory of Electromagnetic Radiation and Sensing Technology, Chinese Academy of Sciences, Beijing 100190, China 2
# An Adaptive Symmetrical Load Balancing Scheme for Next Generation Wireless Networks
## 6 Conclusions  
In this paper, we showcased the load distribution predicament for high density SD-WiFi for the data plane and control plane. We proposed a symmetrical load balancing scheme which comprises traffic shaping and cluster-based traffic classification for both the data plane and control plane. In the data plane we suggested a load distribution strategy, which progressively considers the AP side and the WD side details during load balancing. We built a simulation framework to appraise the load balancing methodologies. Load balancing is also achieved in control plane, to resolve the over loading issue in controllers. The control plane in two tier is managed by a UC. The UC manages all the regional controller in the clusters. AHP is employed to help prioritize the flows and assign packets to least loaded RCs. The extensive simulation runs demonstrate that by clustering and prioritizing packets, notable enhancements in performance can be attained when a symmetrical load balancing is achieved. The performance evaluation show that the ASLB algorithm accomplishes superior load distribution. ASLB has a greater throughput by 40% and lesser delay by 25% compared to the load balancing methods carried out by MPD, CMAS, RSSI and DASA schemes. The proposed ASLB can be implemented to attain better response for time-critical applications. We plan to induce artificial intelligence (AI) into APs to make association decisions themselves in the near future for health care. We are working to use the Mininet-Wi-Fi-NS3 emulation platform for AI enabled APs, which already has the SDN wireless extension libraries.  
Conceptualization, S.M.; methodology, F.M.; software, A.B.; validation, M.U.H., F.R.; formal analysis, H.G.M.; investigation, S.M.; resources, F.M.; data curation, A.B.; writing--original draft preparation, F.M.; writing--review and editing, S.M.; visualization, M.U.H.; supervision, S.M.; project administration, S.M.; funding acquisition, H.G.M. All authors have read and agreed to the published version of the manuscript.  
Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2023 TR140), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.  
Data Availability Statement: Data is contained within the article.  
The authors declare no conflict of interest.  
Figure 10: Actual Throughput Performance.