esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Design and Analysis  
### Structure Optimization and Analysis  
In order to improve the output characteristics of the proposed motor, the optimized design for the motor's configurations can be summarized in the following.  
First, compared with the previous motor, the volume of the driving foot has been improved to enhance the contact area with the slider. Furthermore, according to the molecular attraction theory proposed by [PERSON] and [PERSON] [21; 22], the friction between two metal surfaces could be synthesized as follows:  
\[F_{f}=F_{a}+F_{d} \tag{1}\]  
where \(F_{f}\), \(F_{a}\) and \(F_{d}\) are the friction force, adhesive friction and ploughing friction. For metal materials, \(F_{f}\) mainly depends on \(F_{a}\) and \(F_{a}\) is determined by \(A_{r}\) and \(\tau_{a}\), where \(A_{r}\) and \(\tau_{a}\) represent the real contact area and shear strength, respectively. Therefore, enhancing the real contact area between the driving foot and slider can increase the driving friction force. Based on the above theory, the proposed motor's driving foot has been optimized as a larger rectangular block. However, for ultrasonic motors, it has been considered that an overlarge bottom area of the driving foot will lead to inconformity of the elliptical trajectories of points in the driving area, and this kind of inconformity will make decrease the driving efficiency. As a result, an overlarge bottom area will retard a larger thrust force output. Therefore, a tradeoff between the driving friction force and the driving foot bottom area should be taken into consideration during the design process.  
From another point of view, four faces of the horn have been optimized as an exponential shape so that the effect of energy gathering, the vibration amplitude and the vibration velocity on the driving foot can be enhanced.  
Finally, considering the fixing positions of the motor, each group of PZT ceramic plates of the previous T-shaped motor were divided into two parts, and the vibration energy of the ceramic plates near the end caps was mostly consumed by the material damping. To overcome this drawback, the modified motor's fixing points have been set on the end caps, and the energy has been delivered to the horns' tip ends, where the driving foot is located, instead of being consumed in the end caps.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Time** & **Vertical** & **Left horizontal** & **Right Horizontal** & **Position of** \\  & **Transducer** & **Transducer** & **Transducer** & **Bottom Point** \\ \hline \(t=n\)T & contraction & freedom & freedom & 1 \\ \(t=(n+1/4)\)T & freedom & extension & contraction & 2 \\ \(t=(n+1/2)\)T & extension & freedom & freedom & 3 \\ \(t=(n+3/4)\)T & freedom & contraction & extension & 4 \\ \hline \hline \end{tabular}
\end{table}
Table 1: The vibrational state of the stator in a period of vibration.  
Figure 3: The working principle of the motor.  
From the analysis above, the proposed motor with a modified structure could enhance the mechanical output performance.
## 3 Materials and Methods
### Research Design  
This study was designed as an exploratory case study in a real school setting, using a mixed-methods approach to evaluate the VR intervention. The primary objective of this study was to examine how children with Level 1 ASD demonstrate observable social communication behaviors and emotional responses during and after participating in a VR-based visual novel.  
Virtual reality was used to deliver immersive, individualized learning experiences that minimize the stress and distractions typically encountered in real-life social situations. The intervention was structured as a single one-hour, one-on-one session conducted in a quiet lab space. Children interacted with two narrative-based, decision-driven VR scenarios modeled after visual novels. These sessions were preceded by a brief introduction to communication concepts.  
The study followed a single-group design with pre- and post-intervention evaluations. Over the course of the following week, classroom teachers observed student behavior during typical school activities. They later completed structured questionnaires and participated in interviews, providing both behavioral and experiential feedback on the tool's feasibility and educational value.  
This exploratory case study follows precedent in early-stage ASD (Level 1) intervention research, where small samples allow in-depth observation under realistic school conditions [16; 22]. The focus is on feasibility, not generalizability. Additionally, the limited sample size reflects the study's objective to identify children with ASD within a mainstream educational setting rather than a special education school. This decision was based on the higher likelihood of encountering Level 1 cases in typical school environments. However, the prevalence of students with ASD in such settings is relatively low, and the specific school involved had a limited number of eligible participants available at the time of the study. This was the convenience sample we had access to, as it was not possible to recruit more participants.  
The limited duration of the intervention was due to school-imposed time constraints and the fixed timeline for data collection. Despite these limitations, the study offers important exploratory insights that may inform the design of longer, more scalable interventions in future research.
## 5 Insights and Future Directions
### Application Oriented Surveys  
A variety of routing-related surveys are published so far for WSNs that may focus on various performance aspects such as energy efficiency, security, intelligence, mobility, in-network processing and so on. There are a variety of routing-related surveys that may discuss the fitness of discussed protocols regarding various application areas in WSNs e.g., in [46; 52; 54], the authors have discussed various application areas of WSNs. The authors in [78] have devised a metric that may determine fitness of different secure hierarchical protocols to suitable applications. In [99], the application scenario of atypical hierarchical routing approaches in WSNs is presented. In [109], the authors have highlighted the applications of discussed mobility-oriented hierarchical routing protocols in WSNs.  
In [105], the application of each energy-efficient homogeneous and heterogeneous routing protocol is highlighted. The authors in [114] have extensively discussed the applications of multichannel routing in a comprehensive manner. However to the best of our knowledge, we have not found any routing-related survey in WSNs that may in-depth and dedicatedly analyze the role of routing protocols in performing an application in WSNs. Therefore, there is still a need to publish such routing-related surveys that may highlight the role of WSNs oriented routing protocols in developing critical applications such as water conservation, irrigation, target tracking, border management and so on. On the one hand, the application-specific routing surveys may highlight the indispensable role of routing protocols in bringing forth technological advancements in WSNs. On the other hand, they may bring forth the growing role and necessity of WSNs in bringing comfort in the lives of human beings. Eventually, they may create interest among the readers/ researchers and motivate them to contribute more in this regard.
# Traffic Noise Prediction Applying Multivariate Bi-Directional Recurrent Neural Network
## 2 Materials and Methods
### Data Pre-Processing  
#### 2.5.1 Video Data Pre-Processing  
The numeric video data, containing individual vehicle trajectories, was purchased from DataFromSky, a computer vision company, processing traffic videos. The individual vehicle trajectories were detected as shown in Figure 8. At each time step, the vehicle information, such as vehicle ID, vehicle type, vehicle location (GPS in UTM), vehicle instantaneous speed and acceleration/deceleration, were extracted from the raw video. In terms of vehicle type, we pre-defined the vehicle categories, according to the shape and dimension, and classified them into six categories, including motorcycle, small car, car, medium vehicle, heavy vehicle and bus. No engine information was taken into account, which could be improved in future work.  
Based on the GPS information of each vehicle and each microphone, the distance between the sound source and receiver could be calculated, namely the instantaneous distances between each vehicle and each microphone.
# Synergistic Potential of Optical and Radar Remote Sensing for Snow Cover Monitoring
## 5 Discussion
### Snow Characterization and Analysis of the Recent Climate Change Impacts on Snow Cover  
Based on the analysis conducted in this study concerning the presence of snow in the Iberian mountains, our findings are congruent with other investigations [18; 50]. The results presented here suggest a higher probability of snow presence in higher mountains, along with an extended snow season at higher elevations. In these regions, at higher and colder areas, snow melts later in the spring, and the depletion curve is rather steep due to increased shortwave radiation [77]. Our study found that snowmelt is mainly concentrated in spring in the Iberian mountains, although melting can occur in winter, with the snowpack often experiencing cycles of melting and accumulation. This finding aligns with previous research describing increased winter snowmelt associated with the recent climate change [78; 79]. Moreover, [PERSON] et al. [80] indicated that at mid-latitudes of Eurasia, snowmelt and snow accumulation occur simultaneously due to temperatures above 0 \({}^{\circ}\)C and high rainfall ratios. In the Iberian mountains, as in other temperate regions, snowpacks are consistently close to the zero-degree isotherm, thus, more sensitive to climate change impacts [81; 82]. This research shows a general negative trend in snow cover throughout the snow season in the Iberian mountains, with the winter months (December and January) exhibiting the most pronounced decrease. Future climate projections forecast a warmer climate worldwide, with particularly significant warming trends in temperate mountains during the snow season [83]. This warming is expected to decrease melt rates in these regions [77], leading to an earlier-onset and slower snowmelt [79; 84], and decreasing significatively the amount of accumulated snow and snow cover [85; 86].
# Email Campaign Evaluation Based on User and Mail Server Response
## 3 Data Sets
### Transaction Mails  
As was mentioned earlier, in the case of transaction emails, the goal is not to abort a campaign, but to block a customer who sends a lot of bad transaction emails. Due to the nature of transaction emails, they tend to be sent to recipients whose emails should be confirmed and are in response to recipient actions. For this reason, the attributes resigned count and complaint count are not considered for them. Since in this case we do not have a list of recipients of a known size, it is necessary to count how many transaction e-mails a client has sent in a given period of time (the sent count attribute). Thus, for the given interval, we use seven conditional attributes: sent count, opens count, unique opens count, clicks count, unique clicks count, soft bounced count, and hard bounced count. The values of these attributes were aggregated for the following time intervals (numbers indicate minutes): \((0,1]\), \((1,2]\), \((2,3]\), \((3,4]\), \((4,5]\), \((6,10]\), \((10,15]\), \((15,20]\), \((20,25]\), \((25,30]\), \((30,60]\), \((60,120]\), \((120,240]\), and \((240,360]\). The values for intervals starting from \((6,10]\) were used as conditional attributes for the model (63 attributes).  
We have assumed that we have an undesirable phenomenon when there is a significant average (counting per minute) increase in the number of hard bounces in the last five minutes before a given transaction email is sent. For each customer, the average number of hard bounces per minute in the 48-hour preshipment period was determined. This number was used as the basis for determining the chain indices for the fifth, fourth, third, second, and preceding minutes, respectively. The geometric mean of the chain indices was then calculated to determine the average increase in the number of hard bounces per minute. We assumed that we label a record as bad if the value of this attribute exceeds 2 (100% average growth).  
In the case of transaction emails, it is enough to limit oneself to hard bounces, as a large number of them indicate that the client is seemingly sending transaction emails to unverified recipients. A large number of hard bounces is a negative factor for the credibility of an ESP company, so it is important to minimise this phenomenon. Additionally, the analysis was limited to customers who send many transaction emails--above the median--as only in this group relatively large amounts of hard bounces were observed.
## 3 Numerical Experiments
### Experiment Description and Parameter Settings  
We focus on configuring a BSS, which provides modular battery swapping service for 200 ETs within one year (365 days). The empirical finding from the multi-day travel mileage of ETs shows that the percentage of ETs in the short-distance travel group, medium-distance travel group, and long-distance travel group are 16%, 69%, and 15%, respectively. The time interval is one hour, indicating that one day is divided into 24 time slots. The _SoC_ of an ET at the beginning of the departure time on each day is taken as 100% because ETs are fully charged at home before each daily travel [20]. From real-world data, we estimate the fitting parameters for daily travel mileage distribution of different groups of drivers, departure time distribution, and percentage of travel distance per taxi per hour. Through the aforementioned fitted distributions, we can generate the daily travels of 200 ETs, and thus generate the _BSD_ for 365 days.  
Table 3 lists the relevant parameters in our experiment. As shown in Figure 5, our experiment adopts PG&E corporation's ToU price for commercial electric vehicle charging [28].  
Figure 5: ToU price of PG&E corporation.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameters** & **Values** & **Parameters** & **Values** \\ \hline \(c_{Bm}\) & 141.57 USD/kWh [20] & \(E_{B}\) & 26.5 kWh \\ \(c_{Bm}\) & 1.7 USD/kWh [20] & \(N_{CP}\) & 10 \\ \(r\) & 0.06 & \(L_{B}\) & 5 years \\ \(P_{c}\) & 13.25 kW & \(c_{t}^{peak}\) & 0.38147 USD/kWh [28] \\ \(c_{t}^{off-peak}\) & 0.16824 USD/kWh [28] & \(c_{t}^{super\ off-peak}\) & 0.144497 USD/kWh [28] \\ \(E^{un}\) & 0.177 kWh/km & \(u_{a}\) & 35.6 km/h \\ \(I_{short}\) & 4.664 & \(\sigma_{short}\) & 0.5345 \\ \(I_{medium}\) & 215.77 & \(\sigma_{medium}\) & 73.144 \\ \(\mu_{long}\) & 342.85 & \(\sigma_{long}\) & 95.279 \\ \(T_{w}\) & 1 h & \(SoC_{end}\) & 100\% \\ \(SoC_{ini}\) & 30\% & & \\ \hline \hline \end{tabular}
\end{table}
Table 3: The parameter settings in our experiment.
## 4 Equipment and Methods
### Throughput Measurement and Data Analysis  
Throughput was measured for the control scenario (no interference), when the Line6 Relay G30 wireless sound transmitter was turned off (Figures 6a and 7a); and for the interference scenario, when the sound transmitter was turned on (Figures 6b and 7b).  
Figure 5: Network architecture settings for analyzing the effects of non-IEEE 802.11 interference on throughput of a wireless network under laboratory conditions.  
Throughput was measured in a total of 120 measurements taken in four steps: step 1 was 30 download measurements in the control scenario; step 2, 30 download measurements in the interference scenario; step 3, 30 upload measurements in the control scenario; and step 4, 30 upload measurements in the interference scenario. During all four steps, all devices in the network were kept at a constant distance from one another. All measurements were performed in the control scenario, and the number of measurements in the control scenario is 100.  
Figure 6: Time-averaged view of radiofrequency spectrum on the physical (PHY) layer on the 2.4 GHz band in the (**a**) no interference and (**b**) interference scenarios by averaging over 20 s. The blue line represents d_8 signal, while the two black peaks indicate signal from the sound transmitter. Darker color indicates greater channel use.  
Figure 7: Radiofrequency spectrum activity over time on the PHY layer on the 2.4 GHz band in the (**a**) no interference and (**b**) interference scenarios. The two red vertical lines indicate continuous transmission from the sound transmitter. Darker color indicates greater signal strength.  
were taken exclusively at periods when channel use was minimal in order to minimize interference from Wi-Fi and non-Wi-Fi sources. We confirmed minimal interference by continuously monitoring with a spectrum analyzer.  
Measurements were analyzed in four steps. Step 1 involved obtaining mean values for down- and upload throughput values for each scenario. In step 2, the mean values for down- and upload were tested for normality in order to select Bartlett's or Levene's test for assessing homogeneity of variance in step 3. These steps were performed separately for data obtained in the control or interference scenarios. In step 4, the appropriate two-sample \(t\) test was selected and used to test whether mean throughput differed significantly between the two scenarios. The null hypothesis (Hnull) was defined as no significant difference between the two mean throughput rates.
## 8 Conclusions  
In communication systems, antenna plays a vital role and could be considered the important asset of a communication system. The main focus in this research is the study of state-of-the-art performance improvement strategies and techniques used for bandwidth, gain, and efficiency enhancement, as well as the mutual coupling reduction techniques used in the array of multiple elements or MIMO antenna elements. Different strategies and techniques used for excellent enhancement in the performance of antennas used for 5G and ultrawide band applications has been reviewed. Metamaterials play a multidimensional role in the performance enhancement of an antenna, especially for 5G and wideband application. MMTs not only play a role in the enhancement of bandwidth but have the capability to reduce mutual coupling between the closely collocated antenna elements in MIMOs and the arrays of multiple elements. The role of the EBG structure slots in the radiators with different geometrical shapes in the antenna performance enhancement in terms of bandwidth, gain, and efficiency is included. Reconfigurability is focused as having an important role and solution for different environmental complexities such as surveillance, tracking, and smart-cities scenarios. Reconfigurability techniques for sharing the same aperture for MMwave and sub-6 GHz application is also included. The role of beam steerability and beam forming is studied in detail.  
Conceptualization, I.A. and Q.A.; methodology, I.A.; software, I.A.; validation, H.S. and W.T.; formal analysis, I.A. investigation, H.S.; resources, H.S.; data curation, Q.A.; writing--original draft preparation, I.A.; writing--review and editing H.S. and W.T.; supervision, H.S.; project administration, H.S.; funding acquisition, H.S. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Beijing Key Laboratory of Millimeter Wave and Terahertz Techniques, School of Information and Electronics Beijing Institute of Technology, Beijing 100081, China.  
I am highly indebted to [PERSON] for all the support extended to me in paving the research ideas and shaping my academic career. I must pay gratitude to him for the technical and financial support and boost throughout all academic and research work. It would not have been possible to obtain my research work here without his lasting and sustained cooperation as and when needed.  
The authors declare no conflict of interest.
# Value of Information Based Data Retrieval in UWSNs
## 6 Conclusions  
In this paper, we have proposed the use of VoI in the form of infotentials for solving data off-loading precedence issues in UWSNs. We have proposed a VoI model for UWSNs and developed various measures and metrics to asses system performance. A relationship has already been identified between the quality of information QoI and value of information VoI in [13; 15]. Based on this relationship and the extensive experiments that we have performed, it is reasonable to conclude that employing VoI for path planning algorithms improves the quality of information being retrieved from a UWSN.  
The path planner performance depends on the context of the situation. If the VoI profile in the system is homogeneous, i.e., there are no hot-spots or the valuation ratio \(A_{H}/A_{L}\) is small, then a shortest path algorithm like LPP should be used. LPP is also fuel optimal. In the case of hot-spots, given the valuation ratio \(A_{H}/A_{L}\) is considerably large, greedy algorithms perform better. Hybrid algorithms offer the best of both these strategies by combining greedy and shortest path algorithms.  
Intermediate node visitation improves VoI by saving tour time and, therefore, GIPP and HIPP perform better than their GPP and HPP counterparts respectively. However, if an emergency is classified as so serious that its priority should not be marginalized, then GPP or HPP should be used as they directly visit the node of concern.  
Conceptualization, F.A.K., S.B., S.A.K., L.B. and D.T.; Methodology, F.A.K., S.B. and S.A.K.; Software, F.A.K. and S.A.K.; Validation, F.A.K. and S.A.K.; Formal Analysis, F.A.K. and S.B.; Investigation, F.A.K., S.B. and S.A.K.; Resources, F.A.K., L.B. and D.T.; Data Curation, F.A.K., S.B. and S.A.K.; Writing--Original Draft Preparation, F.A.K., S.B., S.A.K., L.B. and D.T.; Writing--Review & Editing, F.A.K., S.B., S.A.K., L.B. and D.T.; Visualization, F.A.K. and S.B.; Supervision, L.B. and D.T.; Project Administration, F.A.K., L.B. and D.T.  
This research received no external funding.  
The authors declare no conflict of interest.