esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 Related Works  
### Dm Phy  
DM is a secure transmission technology without encryption for physical layer security. It uses antenna arrays to transmit confidential message only along desired directions while distorting signal constellations in all other directions. DM has received great attention in recent years, and it can be classified as PA-DM and FDA-DM. In this paper, we mainly research wireless communication scheme based on DM physical layer security technology.  
PA-DM have been employed in many applications; however, these works based on PA-DM schemes can only achieve angle-dependent wireless physical layer security transmission [8; 9; 10]; Random subcarrier selection (RSCS) based on orthogonal frequency division multiplexing (OFDM) [11] only focuses on the single LU. Unless otherwise stated, other schemes are based on FDA-DM. The AN-aided DM schemes [14; 22; 23; 24; 25; 26] can achieve the multi-beam secure transmission, regardless of the power efficiency. Moreover, those methods cannot achieve the neighbor security because of constraint on beamwidth. Furthermore, in [32], a synthesis scheme combined WFRFT and FDA DM was investigated to achieve power efficiency and the neighbor security. The contributions to physical layer security are solid. However, WFRFT DM schemes cannot guarantee the security of confidential messages when the WFRFT parameters are leaked to Eves.  
On the basis of the previous work, we propose a synthesis multi-beam security communication scheme with the joint use of multiple techniques including MP-WFRFT, SM, and FDA-DM. Moreover, there are four potential practical applications for the proposed schemes in free space.  
The first is the secure transmissions of satellite communications (SatCom) from ground station to satellites or from one satellite to others. The second is the secure transmissions of unmanned aerial vehicles (UAV) from the ground controller to UAVs or from one UAV to others. The third is the secure 5G millimeter wave (mmWave) communication. We can ignore the very few multi-path components in mmWave transmission, and the far-field and LoS assumptions can hold simultaneously due to the tiny array size, usually in magnitude of millimeters. The fourth is application in the Internet of Things (IoT). IoT is an indispensable part of our lives. Traditional security mainly relies on key encryption mechanism, but for the IoT with large number of nodes and heterogeneous networks, it is difficult to extract, distribute, and manage the keys. This has led us to develop new security solutions for IoT applications. Our proposed synthesis scheme based on FDA-DM can achieve security of IoT in physical layer, and it can solve the problem of spectrum scarcity in the IoT due to the SM technology.
## 4 DC-DC Converter Topologies for LEV Charging
### On-Board Charging  
On-board charging remains the most widespread charging method for LEVs, mainly in part due to its simplicity in size and source availability. In a conventional AC-based LEV charging system, there are two stages: AC-DC rectification, followed by a DC-DC PFC stage to ensure smooth input current waveform, and another DC-DC converter to control the battery charging process. However, apart from two-stage LEV chargers, researchers have also reported on single-stage LEV chargers, where a single DC-DC converter is responsible for PFC and control of battery charging [33; 34].  
On-board chargers can exist on the vehicle itself or may be formed as part of the charging cable. Hence, a design objective of on-board chargers is to make it more compact, and hence increase its power density. This ensures that the charger module occupies minimum space on-board the vehicle. Other desirable operational characteristics of on-board LEV chargers are high charging efficiency, high power density and an acceptable input power factor.
## 6 General Recommendations
### Field Strength Dependency
Notwithstanding that SNR is significantly lower, novel reconstruction techniques and artificial intelligence (AI)-based methods can recoup part of the lost SNR compared to 1.5 T and 3 T, and thereby support field strengths <1 T as a valuable alternative to the more established field strengths.
###### Abstract  
Membrane distillation is a thermal separation technique using a microporous hydrophobic membrane. One of the concerns with respect to the industrialization of the technique is the development of novel membranes. In this paper, a commercially available hydrophilic polyethersulfone membrane with a suitable structure for membrane distillation was modified using available hydrophobic coatings using ORMOCER(r) technology to obtain a hydrophobic membrane that can be applied in membrane distillation. The surface modification was performed using a selection of different components, concentrations, and application methods. The resulting membranes can have two hydrophobic surfaces or a hydrophobic and hydrophilic surface depending on the application method. An extensive characterization procedure confirmed the suitability of the coating technique and the obtained membranes for membrane distillation. The surface contact angle of water could be increased from \(27^{\circ}\) up to \(110^{\circ}\), and fluxes comparable to membranes commonly used for membrane distillation were achieved under similar process conditions. A 100 h test demonstrated the stability of the coating and the importance of using sufficiently stable base membranes.  
hydrophobic coatings; direct contact membrane distillation (DCMD); polyethersulfone; ORMOCER(r); wetting +
Footnote †: journal: Applied Sciences
## 3 Measuring Course Effectiveness
### Long-Term Effectiveness  
To evaluate the long-term effectiveness of the course, past participants of the NOAA Satellite Training Course were surveyed in February 2019. Of the 355 total participants, 293 were located and sent surveys and 96 responded, a response rate of 33%. Respondents could remain anonymous. Of respondents, 75% identified as working for the federal government. Participants were asked to assess their current satellite usage and compare it to their usage prior to taking the course (Figure 5). The most dramatic change was reported for the percentage of respondents not using satellite data. Before the course 41% of participants were not using satellite data. After the course only 14% reported not using satellite data. An increase in satellite data use was reported for all other categories (some, moderate, and extensive use) after taking the course, with the percentage of respondents reporting a moderate usage of satellite data doubling from 13% prior to the course to 26% after the course. Overall, these data indicate that participation in the satellite course has been effective at increasing the usage of satellite data, especially in the federal government sector.  
Figure 5: Participants’ self-evaluation of their satellite data usage before taking the satellite course (light gray) and after taking the satellite course (dark gray). Data are from a poll sent out to all participants who had taken the course between 2006 and 2019. Ninety-six responses were received from 293 surveys sent out, a response rate of 33%.
## 3 Experiments and Discussion
### Model Error Analysis for Gaussian Process Modelling
The standard deviations of the measurement noise were simulated to be 0.001 mm, 0.005 mm, 0.01 mm, 0.02 mm and 0.03 mm. The method of evaluation of the performance of the model is similar to previous experiments and the result is shown in Figure 15b. The expanded deviation values of the measurement noise are used in the figure. The result shows that the model error increases when the measurement noise increases in a linear relationship. When the measurement noise is larger than the form error, the modelled error may also be affected by the form error but this is not clearly shown in the result since it may be covered by the effect of the large measurement noise. In general, the experiment results show that the accuracy of the model of Gaussian process modelling is not only affected by the measurement noise but also by the form error of the measured surface, especially when the amplitude of the form error is smaller than that of the measurement noise. Considering that the model error affected by the measurement noise is in the confidence region of the uncertainty modelled by the Gaussian process which is acceptable in the result, the model error affected by the form error is not the same case since it may cause the mean surface to have a bias to the true value which is outside the confidence region of the modelling. This is one of the limitations of Gaussian process data modelling in that it affects the accuracy of the proposed method. Figure 15: The relationship between model error, form error and measurement noise: (**a**) when measurement noise is fixed; and (**b**) when form error is fixed.
# A Bibliometric Analysis and Visualization of In-Vehicle Communication Protocols
## 3 Results  
This bibliometric review was conducted on a dataset comprising 2919 scholarly documents on in-vehicle communication protocols, including CAN, FlexRay, LIN, MOST, and Automotive Ethernet. Almost half of the documents in the dataset were conference papers, suggesting an actively developing field, with 1465 entries (50.19%) for the conference papers. The journal articles group represented a close second with 1324 documents (45.36%), suggesting that academics are considerably engaged with peer-review processes endorsing research validation. Book chapters, although minimal, enhanced the dataset with 86 entries (2.95%), demonstrating their contribution towards comprehensive discourse or niche analysis of specific topics. Review articles were the least frequent, at a total of 44 (1.51%), indicating that while the field is rich in empirical and technical work, there is scant synthesis or consolidation of knowledge available. The observed document distribution indicates a strong emphasis on research and innovation in the technical area of focus. Table 1 shows the types of documents retrieved.
# Enhancing Railway Network Safety by Reproducing Wheel-Rail Electrical Contact on a Laboratory Scale
## 3 Results
### Dependence of the Resistance on the Applied Current
#### 3.2.2 Oxidized Contact: \(R_{c}(I)\)  
Figure 12 shows the evolution of the current imposed on the contact (similar to the previous case) as a function of time, and the corresponding evolution of the contact voltage in the case of an oxidized surface. Figures 13 and 14 show the evolution of the contact resistance and the \(U-I\) characteristics, respectively, during this experiment.  
Figure 11: \(U-I\) characteristics of a clean contact between wheel and rail when increasing the current I (\(\Circle\)) from 0.1 A to 1 A, then decreasing I (\(\square\)) from 1 A to 0.1 A, for F = 400 N.  
Figure 10: Evolution of the current intensity in the contact (\(-\)) and the contact voltage (\(-\)) over time for a clean contact between wheel and rail.  
contact occurs, observed as sudden drops in contact resistance with steps of increasing current. This can be observed at the beginning of the curves in Figures 12 and 13: up to 300 s and indicating a transition to a less insulating state. This behavior could be the result of an improved contact due to the flattening of surface asperities under the effect of mechanical stress and the heating generated by the current. As the current continues to increase, the contact resistance gradually stabilizes, indicating a slower evolution of the contact, as shown in Figure 14 after current increase from 0.6 A to 1 A. As the current decreases, \(U-I\) characteristics become more linear, and the resistance tends to stabilize at a lower level (approximately 9.8 m\(\Omega\)) than its previous values. This behavior is similar to that of a clean contact, as shown Figures 10 and 11, where the voltage is proportional to the current. Overall, the results indicate progressive changes in contact resistance, underlining the influence of current on the electrical properties of an oxidized contact.
## 4 Experiments and Performance Evaluation
### Applied Dataset
#### 4.1.1 SaNAD  
The SANAD dataset is a vast collection of Arabic news stories that may be utilized for various Arabic NLP tasks, including tweet or text classification. The content was gathered using a Python program customized for three famous media websites: Akhbarona, Al-Khaleej, and Al-Arabiya. Figure 3 depicts the distribution of data concerning each class. The dataset is divided into technology, sports, religion, finance, and medicine. Each category contains more than 6000 Arabic text files. Since all of these data were compiled from newspaper websites, the contents are in \"Modern Standard Arabic\", which implies that no accents are included. The datasets are labeled with a single label, and the records are combined into a single corpus termed SANAD. The SANAD dataset contains a large amount of text corpus per category that can produce better performance than the available small dataset that contains 83 to 893 text corpus per label [1; 36].
## 3 Materials and Methods
### Products
#### 3.2.2 Igs-Ztd  
The International GNSS Service (IGS) has been providing the total ZTD products for global monitoring stations since 1997. Between 1997 and 2003, a weighted average combined product was generated by independent products from multiple analysis centers. The product adopts the SINEX format, with a time resolution of 2 h and an accuracy of about 4 mm [36]. Since 2003, a new ZTD product was acquired by the Jet Propulsion Laboratory (JPL) Analysis Center using GIPSY software with Precise Point Positioning (PPP) procedure and Neil Mapping Function (NMF). A 5-minute-resolution ZTD file was provided with an official accuracy of 1.5-5 mm. Due to the systematic error, the actual error is slightly larger [37]. Since 2011, The United States Naval Observatory (USNO) assumed responsibility for producing IGS final ZTD products by Bernese GNSS Software 5.2 [38]. The processing used PPP and the Global Mapping Function (GMF) with IGS final satellite orbits/clocks and earth orientation parameters as input, and the elevation angle cutoff is 7 degrees [39; 40].
# 3D Point Cloud Generation Based on Multi-Sensor Fusion
## 3 A Method of 3D Point Cloud Generation by Multi-Sensor Fusion
### Research on Track Mobile Laser Measurement System (TMLS)  
We mainly integrated sensors such as a Z + F 5016 3D laser scanner, FSINS3X inertial navigation system, inclinometer, rail car and laptop computer in the TMLS, as shown in Figure 3. The track trolley contained a motor, odometer and gauge measuring instruments. It drove at a constant speed on the track at three different speeds of 0.5 m/s, 1.0 m/s, and 1.5 m/s. The odometer scale error was 0.45%. The scanner, IMU, inclinometer, etc. were all controlled by the laptop to start and stop. The IMU, inclination, mileage and gauge data were transmitted to the computer in real time through the serial port and the scanner data was recorded on its own solid-state hard disk.  
Figure 2: Flow chart of point cloud generation based on RTS filtering and smoothing.  
System synchronization mainly included time synchronization and space synchronization. To ensure that the scanner and IMU in the system were consistent in the time system, and that the scanner, IMU and rail car were consistent in the space coordinate system, it was necessary to unify the time and space coordinates of each sensor in the system [23]. Figure 4 presents the coordinate definition of the main sensors in TMLS. The IMU defined the three-dimensional coordinate axis according to the equipment design framework. One X-axis and one Y-axis pointed to the front of the system and the others pointed to the left side of the system. On the right side, the Z-axis was upward. The origin of the scanner coordinate system was the laser emission point, the X-axis was perpendicular to the scanning plane and pointed to the front of the scanner, that is, the front of the scanning section. The Z-axis pointed vertically upward in the scanning plane, and the Y-axis was perpendicular to the scanning plane. The axes were also in the scan plane and perpendicular to the XOZ plane, forming a left-handed coordinate system.  
In terms of time synchronization, the system recorded the system time uniformly in the IMU, inclination and trolley data using the laptop. A Z + F 5016 scanner can automatically record the start time from the scan start time. The system time of the scanner was time unified. In the space synchronization, we adopted the method of system calibration to unify the space coordinate system.  
Figure 4: Schematic diagram of the coordinates of the main sensors of TMLS.  
Figure 3: Track Mobile Laser Measurement System (TMLS).
# Fire Safety Risk Analysis of Conventional Submarines
## 3 Overview of Systems and Risks  
### General Objectives of Submarine Mission and Hazards  
The key submarine mission objectives in the event of a fire are assumed to be (a) Prevent the loss of the submarine; (b) Prevent loss of life and minimise injury where possible; and (c) Maintain stealth and continue mission if possible [5]. However, anecdotal evidence suggested that sometimes the mission (c) gets priority over the crew (b). Note that the order of priority is dependent on the mission and the phase of the mission when the incident occurs which can sometimes mean mission is prioritised above the safety of the crew. The objectives typically require damage control and emergency operating procedures to be enacted to extinguish the fire, restore functionality to the submarine, tend to crew members, retain stealth if at all possible and once the situation is settled, decide to continue the mission or return to base.  
The consequences of fire on a submarine can lead directly to injury and loss of life, however due to the hostile, high-pressure, underwater environment in which a submarine operates, a fire can lead indirectly to loss of the submarine even if the fire is able to be contained. Examples include:  
* Fire damage to the propulsion system or supporting subsystems which compromises propulsion of the submarine, leading to depth excursion, resulting in loss of the submarine.
* Fire and smoke damage causing multiple system failure and compromised ability to monitor and control the submarine, resulting in loss of the submarine.
* Heat from fire reducing the strength of the pressure hull, leading to loss of structural integrity, resulting in loss of the submarine.
* Fire damage and/or firefighting and damage control actions leading to compromise of fluid containment systems, causing internal flooding of the submarine, resulting in loss of the submarine.
* Fires resulting from malfunction of weapon systems, torpedoes and missiles.
# Wheat Yield Estimation Study Using Hyperspectral Vegetation Indices
## 3 Results
### Multiple Methods to Build Models Based on Vegetation Index
#### 3.3.3 Principal Component Analysis Method  
Principal Component Analysis (PCA) extracted three principal components, and when these three components were used for both Multiple Linear Regression and Stepwise Multiple Regression, the accuracy of the yield estimation models was found to be less than 0.6. This lower accuracy suggests that the models had limited predictive power and yielded less than ideal results. It may be necessary to explore alternative modeling techniques or consider additional variables to improve the accuracy of the yield estimation models.
## 4 Results and Discussion
### Good Quality Papers  
Some papers were filtered based on the \"Good quality\" of the contribution of the paper. The overall distribution of these papers based on the frequency of the application domain to which these papers belong is shown in Figure 12. Based on the statistics, good quality papers show the support of decision support systems in five application domains such as \"General problem solving\", \"Industrial domain\", \"Energy sector\", \"Agriculture\", and \"Transportation\" having a frequency of 7, 6, 6, 5, and 10, respectively. All these \"Good quality\" contributions are represented in more detail in Table 10 along with their short description, year of publication, application domain, and quality level. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Citation** & **Short Description** & **Year** & **Application Domain** & **Quality** \\ \hline
[69] & In this paper, the authors exploit two multiple-criteria decision-making algorithms in a web-based system. The proposed work classifies and ranks the rural areas of Central Macedonia in Northern Greece. & 2016 & Agriculture & Good Quality \\ \hline
[29] & The study proposed GDSS for the agriculture supply chain in France. GDSS uses quality function deployment (QFD) and technique for order preference by similarity to the ideal situation (TOPSIS) to select a logistics provider. The proposed system aids the agricultural partners and investors in the selection of third-party logistic providers. & 2017 & Agriculture & Good Quality \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Details of good quality papers with their description. Figure 12: Distribution of good quality papers.
## 4 Discussion
### Transport and Enrichment of Iron in Trticulum aestivum_ L.  
The average transport coefficients of iron in the jointing stage and mature stage of _Trticulum aestivum_ L. were 0.316 and 0.411, respectively, both of which were less than 1. This suggests that the transport capacity of iron in the soil by different parts of the _Trticulum aestivum_ L. plant is low. As _Trticulum aestivum_ L. grows, its transport capacity generally increases. Specifically, at a concentration gradient of 7.2 mg/kg, the translocation factor from underground to aboveground is the highest during the jointing stage, and the enrichment coefficient of roots and stems corresponding to this concentration gradient is the highest at maturity. Combined with the knowledge obtained by the aforementioned studies on the mechanism of iron accumulation in _Trticulum aestivum_ L under iron deficiency stress, the authors suggest that maintaining an iron-deficient soil environment is beneficial for the growth of _Trticulum aestivum_ L. Previous studies have indicated that the application of iron fertilizer can alleviate iron deficiency symptoms in plants. However, it has been observed that applying iron fertilizer to plant roots or leaves can rapidly desensitize the plant roots' response to iron deficiency stress [44; 45]. Therefore, this experiment holds significant reference value for determining the amount of iron fertilizer to be applied to the roots. Given that this experiment was conducted in a highly alkaline soil background, the concentration level of the added iron ion solution should be determined by studying iron transport in various soil backgrounds.  
Chlorosis, resulting from iron imbalance in calcareous soil, is widespread in northwest and north China. It affects trees, fruit trees, pastures, vegetables, and field crops, with fruit trees being especially vulnerable to chlorosis compared to annual crops, resulting in a significant decline in fruit product quality. The application of iron micro-fertil is a rapid and effective method to alleviate symptoms of iron deficiency in plants. The type of iron fertilizer and its application mode can significantly impact the utilization efficiency of iron in plants. This study can offer valuable insights into enhancing plant iron nutrition by promoting efficient iron uptake and transport through regulatory measures, such as fertilization methods and planting patterns.