esa-sceva/satcom-chunk-collection huggingface dataset:
# HISEA-1: The First C-Band SAR Miniaturized Satellite for Ocean and Coastal Observation
## 2 Typical Data and Preliminary Results
### Dark Spots in Image of Kerch Strait  
Kerch Strait is located in the Black Sea. The surface salinity of the Black Sea is low because of the freshwater injection from rivers and low-salinity water injection from the surface of the Mediterranean Sea. However, high-salinity water flows deep into the Black Sea, which is a consequence of the fact that the water is a  
Figure 3: One-meter resolution spotlight-mode SAR image of Xiamen University Siming Campus, the gridding size is 1937 \(\times\) 4750 (horizontal \(\times\) vertical). The left red rectangle border indicates the high-rise area, which shows some 3D features of buildings. The right red rectangle indicates the main part of the campus. The oval borders indicate the high rises’ location.  
Sea from the Mediterranean Sea. Therefore, there is nearly no interaction between deep and shallow waters [29]. The Azov Sea is the shallowest in the world. Kerch Strait is an important waterway between the Black Sea and Azov Sea [30].  
Figure 4 shows the striping-mode SAR image of the Kerch Strait. Different cultivated lands appeared as regular squares. The Kerch Strait Bridge spans the strait, and many ships and their wakes are shown in the image. The dark spots in the sea may be oil slicks, upwelling, rain cells, or low-wind-speed areas. The oil film also makes it convenient to study some marine phenomena such as vortexes [31]. Note that the dark spots in Figure 4 were located in the coastal area, so the spots show the polluted domestic water discharged into the ocean. The shape features of dark spots also reveal the current direction. As a result, some features of the air-sea interface phenomena in those dark spots areas could be more easily observed by SAR. The strips of the dark spot at the lower-left corner of the image were the wind streaks. The current under the Kerch Strait Bridge appeared as regular strips, and some vortex structures were also found at the bottom of the image.
## 3 ML-Based Routing Algorithms in WSNs
### Artificial Neural Network-Based Routing Methods
The distance \(d[v_{j},v_{r}]\) of node \(v_{i}\) to the base station \(v_{r}\), can be expressed as:  
\[d[v_{j},v_{r}]=d[v_{i},v_{r}]*QoS, \tag{8}\]  
where \(QoS\) is the corresponding channel quality. Due to the bottleneck of data processing ability and energy in WSNs, the task and learning process of ANNR with high computational cost should be implemented through a central data processing unit. In contrast, sensor nodes can implement the execution process that does not require a high computational cost. This hybrid algorithm takes into account the QoS requirements when defining the edge weight coefficients and can achieve the best route with a low average dissipation energy and average delay. To design an energy-efficient routing scheme, a resilient routing algorithm was proposed [67], which considers the link reliability and other traditional routing metrics and utilizes a deep-learning-based link prediction model. To improve the self-learning capability of mining topological features, this model combines Weisfeiler-Lehman kernel and dual convolutional neural network (WL-DCNN) for lightweight subgraph extraction and labeling. Then, the link state information is used to design a resilient routing mechanism based on a combination of the current shortest path and link reliability metric, which achieves energy efficiency and extends the lifetime by ensuring data integrity and shortening the transmission path. To ensure energy efficiency and QoS, a secure deep learning (SecDL) approach was proposed [68], where the topology is formulated as a biconcentric hexagon network along with mobile sink to improve energy efficiency. The hexagonal network is first divided into six sectors, and the dynamic clusters are formed in a self-organizing manner. Each cluster performs cluster head selection, minimization of redundant data, and data aggregation. In the data transmission, the optimal route is selected in SecDL by combining trust parameters, QoS parameters, and energy-efficiency parameters. Figure 8: The ANNR model with self-organizing map architecture [66]. (Reprinted with permission from ref. [66]). In general, ANN can provide adaptive capability for routing protocols with dynamic topology in WSNs. However, the main defects are the complexity of the algorithm and the learning overhead in the case of dynamic topology.
## 2 Materials and Methods
### ROS Scavenging Efficacy  
The intracellular active oxygen scavenging effect was measured using the principle that 2\({}^{\prime}\),7\({}^{\prime}\)-dichlorofluorescein diacetate (DCFH-DA) non-fluorescent material reacts with free radicals generated in cells and oxidizes to fluorescent 2\({}^{\prime}\),7\({}^{\prime}\)-dichlor fluorescein (DCF). HDFs were cultured for 16 h in a 96-well plate at 0.8 \(\times\) 10\({}^{5}\) cells/mL. Then, HDFs were pre-treated with 50, 100, or 200 \(\mu\)g/mL TVEE for 1 h, followed by treatment with 0.85 mM H\({}_{2}\)O\({}_{2}\). After incubation for 30 min, DCFH-DA was added. The degree of intracellular free radical production was measured based on DCF fluorescence intensity in the range of 485 nm \(\lambda\) excitation and 528 nm \(\lambda\) emission [23].  
In addition, the effect of TVEE on intracellular ROS production in H\({}_{2}\)O\({}_{2}\)-induced HDFs was confirmed using a fluorescence microscope (Nikon Eclipse 80i, Nikon, Tokyo, Japan). HDFs (5 \(\times\) 10\({}^{5}\) cells/mL) were cultured for 16 h in a 60 mm cell culture dish with a coverslip. Then, the cells were incubated with 50, 100, and 200 \(\mu\)g/mL TVEE for 1 h, and treated with 0.85 mM H\({}_{2}\)O\({}_{2}\). After incubation for 30 min, the treated cells were stained with DCFH-DA, washed with PBS, and observed under a fluorescence microscope.
## 4 Biological Activities of _Passiflora caerulea_ L.
### Antibacterial Activity  
Many studies have been conducted on the antibacterial properties of medicinal plants, emphasizing their potential as a substitute for conventional treatments for bacterial infections, particularly in the context of antibiotic resistance. In recent years, there has been an increase in the interest in plant extracts demonstrating antibacterial activity [43].  
Recent investigations have highlighted the antibacterial properties of _P. caerulea_, demonstrating its efficacy in combating a range of pathogenic bacteria. [PERSON] and [PERSON] explored the antibacterial activity of the methanolic leaf extract of the plant (in a concentration range of 100-1000 \(\upmu\)g/mL) against two Gram-negative bacteria--_Escherichia coli_ (ATCC25922) and _Pseudomonas aeruginosa_ (ATCC 27853) [23]. The results showed a higher inhibitory effect against _E. coli_ than against _P. aeruginosa_. The findings of [PERSON], [PERSON] and [PERSON], who investigated the antibacterial activity of other _Passiflora_ species against Gram-negative bacteria--_Pseudomonas aeruginosa_ (ATCC 27853). _Klebsiella oxytocin_ (ATCC 49131), _Proteus vulgaris_ (ATCC 49132), _Salmonella enteritidis_ (MTCC 125239) and _Escherichia coli_ (MTCC 423155)--also reported that the methanolic extract of the plant showed considerable inhibitory activity [44]. In contrast, in the study by [PERSON] et al., the 50% methanolic and 70% ethanolic extracts of the leaves and pulp of _P. caerulea_ demonstrated limited antimicrobial activity (inhibition zones \(<\) 12 mm) compared to the antibiotics used [17]. No activity has been shown against Gram-positive bacteria _Staphylococcus aureus_ ATCC 25923 and _Listeria monocytogenes_ NBIMCC 8632 nor the Gram-negative _Klebsiella pneumoniae_ ATCC 13883 or _Proteus vulgaris_ ATCC 6380. In research by [PERSON] et al., the pulp extracts showed antifungal activity against _Penicillium chrysogenum_ and _Fusarium moniliforme_. When evaluating the antimicrobial activity of fruit extracts, the strongest inhibitory activity has been shown in the ethanolic extract of _Passiflora caerulea_ against _Pseudomonas aeruginosa_ (ATCC 27853), and the lowest effect was against _Escherichia coli_ (MTCC 423155) [45]. The inhibitory effect of _P. caerulea_ against _Bacillus cereus_ and _E. coli_ has been investigated recently [40]. The results showed that the methanolic leaf extract and chloroform leaf extract inhibited the growth of _B. cereus_ (MTCC-430) and _E. coli_ (MTCC-118), respectively. _Passiflora caerulea_ shows important antimicrobial properties, with research indicating its potential applications in fighting bacterial and fungal infections thanks to its abundant phytochemical content.
# Cross-Domain Fake News Detection Using a Prompt-Based Approach
## 4 Experiments
### Experimental Setting  
We conducted all experiments on NVIDIA A100 GPUs using PyTorch v2.4.0, a popular DL framework. Our dataset (Section 4.2) included real and fake news articles from various domains with varying lengths. To ensure a consistent input size and facilitate training, we truncated or padded these news articles to a maximum of 256 tokens, focusing only on the first 256 words. This choice was made after an analysis revealed that only 7 articles exceeded this limit by a small margin, while 1156 articles were shorter. This truncation/padding approach allowed us to maintain uniformity across the dataset. Additionally, using the first tokens of the English-language dataset yielded the best performance in our previous experiments [20]. We employed the Adam optimizer, a widely used adaptive learning-based rate optimization algorithm that has been proven to be effective for various DL tasks. The learning rate was set to \(3\times 10^{-5}\) (an empirically defined value). Such hyperparameters in our model were primarily chosen through trial and error. We utilized the small variant of the GPT2 model, with 117 million parameters. Unlike traditional methods predicting class labels directly, we framed the text classification task as a conditional generation. This approach leverages prompt engineering, incorporating a specific (context-aware) prompt with the input text. This prompt influences how the model interprets the data. Subsequently, the model generates a sequence of tokens representing the predicted class label (e.g., \"fake\" or \"real\").
## 4 Conclusions  
Cavitation bubbles seriously affect the performance and service life of hydraulic devices such as hydraulic valves, water pumps, and marine propellers. It is urgent to study the mechanism of cavitation erosion in order to prolong the service life of hydraulic machinery. A cavitation test system was built, and four kinds of metallic samples--brass, red copper, aluminum alloy, industry pure aluminum--were used to investigate the behaviors of cavitation erosion on the metal surface. The experimental results showed that these four different materials had different anti-cavitation erosion abilities because of their different yield strengths. The anti-cavitation ability of brass was obviously better than that of the red copper, pure aluminum, and aluminum alloy. The weight loss and cavitation erosion rate of the brass were the lowest while the pure aluminum had the largest. The surface of the brass only produced pinhole-like pits, while the pure aluminum sample had serious cavitation damage, which presented a honeycomb-shaped surface topography. Furthermore, the roughness of the surface topography plays an important role in cavitation erosion. Because the roughness of the brass machined by milling was greater than grinding, the milling brass sample could increase the pressure loss along the flow path and the suppressed cavitation strength. However, there is not a simple linear relationship between the roughness of the surface and the degree of the cavitation erosion and a reasonable surface morphology could inhibit the occurrence of cavitation.  
Conceptualization, J.H.; Methodology, X.L.; Software and validation, B.L.; Formal analysis and data curation, J.Z.; Writing--original draft preparation, J.S. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (grant number 51875559).  
Not applicable.  
The authors declare no conflict of interest.  
Figure 9: (a) The cumulative weight loss curves of the brass specimens with increasing acting time. (b) The cumulative weight loss curves of the brass specimens with increasing acting time.
# Effects of Cement-Mineral Filler on Asphalt Mixture Performance under Different Aging Procedures
## 2 Test Materials and Methods
### Test Design and Method  
In this study, the above mixture ratio was used to prepare the mixture, and the total proportion of the filler used was 4%. To compare and analyze the influence of different proportions of cement-mineral filler on the long-term performance of the asphalt mixture, this study designed combinations of two types of fillers with five ratios; note that the total mass ratio after the combination of the two fillers was not changed. For convenience, the mass ratio of Portland cement and mineral powder was recorded as \(\text{M}_{\text{PC}}/\text{M}_{\text{MP}}\). Hence, the five combination ratios were 0:4, 1:3, 2:2, 3:1, and 4:0, and the content of the corresponding cement substitute mineral powder was 0%, 25%, 50%, 75%, and 100%, respectively.  
The asphalt mixture mixed in each proportion was tested for road performance under three different aging procedures. The three aging procedures were no aging, short-term aging, and long-term aging, as per the China Highway Engineering Asphalt and Asphalt Mixture Test Regulations (T 0734-2000) methods. Naturally, the three aging procedures correspond to different degrees of aging. The long-term aging procedure is the deepest, followed by the short-term aging procedure [33].  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Gradation Range**} & \multicolumn{8}{c}{**Passing Ratio (\%)**} \\ \cline{2-13}  & **26.5** & **19** & **16** & **13.2** & **9.5** & **4.75** & **2.36** & **1.18** & **0.6** & **0.3** & **0.15** & **0.075** \\ \hline Upper limit & 100 & 100 & 92 & 85 & 75 & 53 & 44 & 32 & 24 & 18 & 4 & 7 \\ Lower limit & 100 & 95 & 78 & 65 & 48 & 23 & 16 & 12 & 10 & 7 & 8 & 3 \\ Synthetic grading & 100 & 97.7 & 86 & 70.3 & 59 & 33.8 & 23.8 & 16.8 & 13 & 8.4 & 6.4 & 5.6 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Grading composition and technical requirements of AC-20 asphalt mixture.  
Figure 1: The appearance of the two types of fillers.  
The short-term aging test piece was compacted after ventilating the loose asphalt mixture at 135 \({}^{\circ}\)C for 4 h. The long-term aging involved ventilation of the test piece that was compacted after short-term aging in a constant-temperature oven at 85 \({}^{\circ}\)C for 5 d. The specific research process is shown in Figure 2.
## 3 Scientometric Analysis: Results and Discussion
### Science Mapping
#### 3.2.2 Mapping of Countries  
In our preliminary analysis, we included a total of 87 countries in this study. Figure 5 shows the relationship between the number of countries and the number of documents published in the field. The results show a low concentration of documents per country; furthermore, 11 countries published only 1 document, followed by 18 countries with only 2 documents published; these countries represent 46% of the total sample.  
To identify countries with greater importance in the field, journals with a minimum of five documents and five citations of a source were identified, resulting in 33 countries. The top 10 of these countries in terms of publication count, total citations, and average normalized citations are summarized in Figure 6. A total of 16 countries are included in the three top lists. India, China, and the United States lead the rankings in terms of the number of documents, with more than 50 publications; China, Canada, and Portugal lead for citation rankings; Portugal, Canada, and Peru lead in terms of average normalized citations. Three of the top lists (Banglades, Canada, China, and Spain) are included in the three rankings, so they could be considered the countries with the most influence in the research in the field; six countries (Australia, India, Italy, The United States, Portugal, and South Korea) are in two of them; eight of them are included in only one of the lists (Saudi Arabia, The United Kingdom, France, Iran, Malaysia, and Peru).  
Figure 5: Relationship between the number of countries and the number of documents published.  
Figure 6: Countries with greater importance in the field, in terms of publication count, total citations, and average normalized citations.  
Finally, Figure 7 presents the network visualization of the 16 countries included in the three top 10 lists in terms of total citations. All of them are linked based on citations, and the degree to which a country has contributed to the research in this field is indicated by the size of the box. Three groups or clusters were detected, denoted by distinct colors: red (Cluster 1), green (Cluster 2), and blue (Cluster 3), with seven, five, and four countries in each one, respectively. Based on the graphical description of the active countries, the large size of the circles of China makes clear the aforementioned leadership of this country in terms of total citations. Our analysis will support researchers working jointly in scientific collaborations to share approaches and ideas and produce papers.
## 2 Materials and Methods
### Satellite Data and Preprocessing
#### 2.1.2 FPAR Products  
In this paper, the FPAR products of MODIS, GEOV1, and GLASS were used for the cross-validation of FPAR inversion, and their specific characteristics are shown in Table 2. The data preprocessing of FPAR products includes extracting sub-data sets, projections and transformations, splicing and cropping, and band operations (FPAR* scaling factors) to obtain a valid range of FPARs.  
* MODIS FPAR products: MOD15A2H products are available on the Level-1 and Atmosphere Archive & Distribution System Distributed Active Archive Center at Goddard Space Flight Center (LAADS DAAC) ([[https://ladsweb.modaps.eosdis.nasa.gov](https://ladsweb.modaps.eosdis.nasa.gov)]([https://ladsweb.modaps.eosdis.nasa.gov](https://ladsweb.modaps.eosdis.nasa.gov))).
* GEOV1 FPAR products: These products result in two outputs with a spatial resolution of 300 m and 1 km. The former was based on the PRoject for On-Board Autonomy-Vegetation (PROBA-V) sensor, with a time coverage from 2014 to the present. The latter was based on the SPOT Vegetation (SPOT-VGT) and PROBA-V sensor, with a time coverage from 1999 to the present. For this work, the  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Channel**} & \multicolumn{2}{c}{**Center**} & \multirow{2}{*}{**Band Width (\(\mu\)m)**} & \multirow{2}{*}{**Band Range (\(\mu\)m)**} & \multicolumn{1}{c}{**Radiation**} \\  & **Wavelength (\(\mu\)m)** & & & **Sensitivity (\%)** \\ \hline
1 & 0.47 & 0.05 & 0.45\(-\)0.50 & 0.30 \\
2 & 0.55 & 0.05 & 0.53\(-\)0.58 & 0.30 \\
3 & 0.65 & 0.05 & 0.63\(-\)0.68 & 0.30 \\
4 & 0.86 & 0.05 & 0.84\(-\)0.89 & 0.30 \\
5 & 11.25 & 2.5 & 10.00\(-\)12.50 & 0.40 \\ \hline \hline \end{tabular}
\end{table}
Table 1: The 250 m resolution channel specification of MERIS.  
Figure 2: The spectral response function of the FengYun-3C (FY-3C) MERSI data.  
former FPAR product with a better spatial resolution (300 m) was selected. Data for GEOV1 FPAR are available on the Copernicus Global Land Service (CGLS, [[https://land.copernicus.eu/global/](https://land.copernicus.eu/global/)]([https://land.copernicus.eu/global/](https://land.copernicus.eu/global/))).
* GLASS FPAR products: GLASS09A01 products were released by the Center for Global Change Data Processing and Analysis at Beijing Normal University. Data for the GLASS FPAR products were taken from the National Earth System Science Data Sharing Service Platform ([[http://www.geodata.cn/thematicView/GLASS.html](http://www.geodata.cn/thematicView/GLASS.html)]([http://www.geodata.cn/thematicView/GLASS.html](http://www.geodata.cn/thematicView/GLASS.html))).
## 5 Performance Evaluation  
### Experimental Environment  
We evaluate our scheme in terms of energy efficiency and recovery latency. Table 2 describes the parameters used for the evaluation. The value of the parameters is based on [24], a study that investigated the transmission power and the communication latency in UWSNs.
## 4 Conclusions  
In this study, factors affecting HF re-orientation in DHF are analyzed by laboratory experiments in transparent gelatin samples with a self-developed experimental device. The following conclusions are made based on the experimental results:  
* It is the relative magnitude of the differential stress and the gelatin elastic modulus that determines HF re-orientation rather than the absolute magnitudes of these two factors. HF re-orientation occurs even if the differential stress ranges from 1000 to 2000 Pa, as long as the gelatin sample also has relatively low elastic moduli.
* Both the re-orientation distance and the geometry of the HF are dependent on the combined effect of the differential stress and the gelatin elastic modulus.
* The HF tends to propagate asymmetrically in gelatin samples with low elastic moduli and under high differential stresses. Asymmetrical, step-like HF geometry is found in the test case that has the lowest gelatin elastic modulus and the highest differential stress, which indicates that both shear failure and tensile failure happen during HF re-orientation.
* HF re-orientation is not necessarily a near-borehole effect, and HFs can propagate along the notch direction for longer distances in stiffer gelatin samples under relatively low differential stresses (1000 Pa and 1500 Pa). For the gelatin concentrations considered in this study (6%, 8%, and 10%), the promotion of DHF by high gelatin elastic moduli is limited once the differential stress reaches 2000 Pa.
* In field applications, DHF is recommended to be conducted on a relatively small scale and in strong, massive rock masses under low or moderate differential stress states. Otherwise, the hydraulic fracturing strategy needs to adjust to the minimum in situ stress direction.  
Methodology, B.L.; Writing--original draft, H.Z.; Writing--review & editing, Q.H. All authors have read and agreed to the published version of the manuscript.  
The work of this paper is financially supported by the National Key R&D Program of China (2022 YFC2905600) and the National Natural Science Foundation of China (51974293).  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The corresponding author of this paper would like to thank his deceased grandmother, [PERSON], for the love and care received from childhood.  
The authors declared that they have no conflicts of interest to this work.
# Mars to Earth Data Downloading: A Directory Synchronization Approach
## 5 Experiment Description
### Data Flow Generation  
#### 5.2.1 Direct Approach  
With the direct approach each data flow is generated by an instance of the DTNperf client [17] (7 in total), which allows the user to set the specific parameters of the data flow, such as destination, priority, bundle dimension and generation rate. Bundles are received by one of the four instances of the DTNperf server, running on Lander, Orbiter, ESA-MCC and PDGS. Status reports are collected by a DTNperf monitor on ESA-MCC. The whole experiment is managed by a \"do-test\" script running on the host, which is connected to all VMs by means of a dedicated control network, with ideal links (no delay, no losses, no disruption).