esa-sceva/satcom-chunk-collection huggingface dataset:
# Comprehensive Investigations on Fluid Flow and Cavitation Characteristics in Rotating Disk System
## 3 Simulation Analysis
### Mesh Model Analysis  
Due to the rotational periodicity of oil film and the time consumption in mesh division, the 1/30 oil film model is chosen for the analysis, and its parameters are shown in Table 2.  
Figure 14 depicts the oil film flow field model when the rotating disk is textured with regular-arranged hexahedral micro-dimples. The textures are distributed 0.5 mm from the center of the adjacent textures along the radial direction and \(1^{\circ}\) from the center of the adjacent textures in circumferential direction. Figure 15 depicts the oil film model with a texture rate of 3.205%.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Values** \\ \hline Inner radius \(r_{1}\) (mm) & 27 \\ Outer radius \(r_{2}\) (mm) & 32 \\ Center angle \(\theta\) (\({}^{\circ}\)) & 12 \\ Default thickness \(h_{0}\) (mm) & 0.1 \\ Default depth of texture \(h_{t}\) (mm) & 0.0564 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Oil film model parameters.  
Figure 14: Schematic diagram of friction pair structure.  
Based on the literature review, cavitation is more likely to occur at high speeds, so the speed \(n\) is set to 6000 rpm, the inlet pressure \(p_{0}\) is set to 0.8 MPa, and the fluid's initial temperature is set to room temperature, \(T_{0}\) = 293 K. Figure 16 depicts the boundary conditions for the simulation model.  
To eliminate the influence on the accuracy of the calculation results, most CFD simulation studies require mesh independence verification of the meshing. In comparison to cylindrical and hemispherical texture oil films, hexahedral texture meshing is relatively simple [41]. The cavitation volume fraction is used to determine computational accuracy and convergence under steady-state simulation conditions, and then to choose an appropriate meshing strategy. As in Table 3, Schemes 1-3 use different axially divided layers, Schemes 2-5 use different circumferentially divided layers, and Schemes 4-7 use different radially divided layers. Results show that increasing the number of axial layers excessively would cause simulation divergence, and the inaccuracy of the calculation results corresponding to different circumferential division of layers was smaller. Scheme 6 was chosen as the final meshing scheme to ensure calculation accuracy and save calculation time.
# Research on Path and Sequence Planning for Multi-Cabin Onboard Transportation of Large Cruise Ships
## 4 Multi-Transportation Path Planning Based on the Improved A-Star Algorithm
### Definition of the Grid Map  
Due to the specific requirements of the large cruise ship push-in operation, modular cabins must be transported within the ship's interior. To limit the scope of path search, the outer plate position of the cruise ship is set as the boundary of the map. Given the large number of cabins and the complex internal structure of the cruise ship, an inappropriate grid division may lead to an inaccurate representation of each module and obstacle, thus affecting the efficiency and accuracy of the path planning. Therefore, simplifying the map model by selecting an appropriate grid size is a crucial step to improve both the efficiency and accuracy of the cruise ship push-in path planning.  
When performing the grid mapping, the following factors need to be considered:  
1. The grid size should be uniform to facilitate accurate calculation of push-in path distances and time.
2. The grid should evenly cover each deck of the ship's structure to ensure comprehensive path search.
3. Multiple modules should not occupy the same grid cell, to avoid interference and conflicts between the cabins.
4. Existing cabins and other obstacles should be represented by one or more grids to accurately reflect their position and shape.
5. A grid cell should not simultaneously contain both obstacles and modular cabins, to avoid interference and misjudgment during the path search.
6. Bulkheads and outer plates, as boundary constraints, must lie on the grid lines to limit the scope of the path search.
7. The grid should be as simple as possible to facilitate computation and reduce calculation time.  
Based on the above analysis, this study divides the decks into rectangular grids, each measuring 7440 mm along the ship's width and 2900 mm along the ship's length. Under this grid division, the research object can be fully partitioned, ensuring that each modular cabin corresponds to a unique grid point, and the bulkheads align with the grid lines. The origin of the grid map is set at the starboard side near the art of the ship, with the x-axis extending along the ship's length from the stern to the bow, and the y-axis extending along  
Figure 8: Large cruise ship deck plan.  
Figure 9: Scheduled installation positions of modular cabins.  
the ship's width from starboard to port. The grid at coordinates (32, 4) represents the push-in entry point for all modular cabins.  
The simplified grid map of the foredeck push-in section of the large cruise ship's first deck is shown in Figure 10. In this map, the horizontal axis of the coordinate axis represents the length direction of the ship, the vertical axis represents the width direction of the ship, the thick solid lines represent bulkheads (line obstacles), the diagonal-filled grids represent non-prefabricated cabins (grid obstacles), and the grid cells filled with square lines represent the target locations for the transportation of all modular cabins.
## 3 Results and Discussion
### Investigations on TRC Coupons
Monitoring the static tests up to failure with DIC measurements enabled to map cracking patterns and measure crack widths and spacings. The average, maximum and total crack widths were calculated from the measured displacement fields for each specimen separately at different stress levels. In addition to the crack spacing itself, the cumulative frequency was also determined to quantify the degree of saturation, i.e., the ratio of actually formed cracks to the total number of cracks at failure. To compare the different series to the reference behavior, the average per series was calculated out of the average and total crack width, the crack spacing and the cumulative frequency. For the maximum crack width, the absolute maximum crack width observed over all specimens within one series was determined. The maximum crack width is an important parameter for designing concrete building elements regarding durability measures, decisive for the ingress of aggressive materials. Looking at the cumulative frequency one could observe that more cracks were formed at lower stress levels for TRC CYCL 0.5 MPa, TRC CYCL 1.0 Mpa, and TRC CYCL 2.0 MPa., while for TRC REF 20% of the total amount of cracks were still formed at stress levels above 4.0 MPa (Figure 13a). The crack spacing showed a discrepancy between TRC REF and TRC CYCL 0.5 MPa versus TRC CYCL 1.0 MPa and TRC CYCL 2.0 MPa (Figure 13b) again. For TRC CYCL 1.0 MPa and TRC CYCL 2.0 MPa cracks originated at lower stress levels leading to a diminished crack spacing. As observed for the cumulative frequency, the crack patterns of the cyclically preloaded series were nearly complete at the stress level of 2.5 MPa. At all stress levels, the crack spacing of these series was lower compared to TRC REF, leading to the conclusion that more cracks were formed for TRC CYCL 0.5 MPa, TRC CYCL 1.0 Mpa, and TRC CYCL 2.0 MPa. Other than for TRC REF and TRC CYCL 0.5 MPa, TRC CYCL 1.0 Mpa, and TRC CYCL 2.0 MPa showed cracks already at stress levels lower than 1.0 MPa (Figure 14), as a consequence of the fact that cracks were already formed during the cyclic preloading. This is displayed for all studied parameters. Looking at the average crack width, a discrepancy was observed for stress levels below 2.0 MPa and above 2.0 MPa: at lower stress levels, TRC CYCL 1.0 MPa and TRC CYCL 2.0 MPa had a higher average crack width, while for higher stress levels, wider cracks were measured for TRC REF and TRC CYCL 0.5 MPa (Figure 14a). The same tendency was seen for the maximum crack width but less pronounced (Figure 14b). Since this maximum crack width was strongly related to the durability requirements, one could state that the impact of repeated loading on durability measurements is little. The lowest total crack width was observed for TRC REF and this at all stress levels. (Figure 14c). Figure 13: The number of cracks present in the different samples was used to compare: (**a**) the average cumulative frequency and (**b**) the average crack spacing.
## 3 Results
### Responses of the SIF-IWUE Relationship to the Environmental Factors
#### 3.3.5 Effects of Observation Time on IWUE-SIF Correlations  
SIF emission has successfully been retrieved from measurements provided by spaceborne spectrometer such as GOSAT [44], GOME-2 [45], SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) [46], and Orbiting Carbon Observatory 2 (OCO-2) [47]. They have the following different overpass times: 09:30 a.m. for GOME-2, 10:00 for SCIAMACHY, 12:00 for GOAST, and 13:30 for OCO-2. Also, both WUEs and SIF emission have strong diurnal cycles (Figures 1 and 2). For an appropriate use of remotely-sensed SIF data for retrieving WUEs at a large scale, it is particularly important to assess the impact of observation time of day on the SIF-IWUE relationship. To do so, we separate hourly SIF emission and IWUE into three different groups: morning (7-10), midday (10-15), and afternoon (15-17).  
The results suggest that the observation time exerts a clear impact on the SIF-IWUE relationship at the canopy level. In comparison to \(R^{2}\) in the morning and midday, there are systematically stronger correlations in the afternoon (Figure 7). Also, the SIF-IWUE correlations at midday are better than those in the morning (Figure 7). In fact, the SIF-IWUE correlations in the afternoon are better than those derived from the daily daytime dataset (Tables 2 and 3). For example, SIF\({}_{761}\) has a strong correlation with IWUE in the afternoon, with \(R^{2}\) reaching a value of 0.60 and 0.69 for the LR and GPR (Figure 7). However, its performance is as high as 0.52 and 0.39 in the morning and midday, respectively (Figure 7). In the afternoon, the band combinations, together with the GPR, also yield a predictive advantage over those derived over the whole daytime (Table 3, Figure 7b). The combination of SIF\({}_{687}\), SIF\({}_{720}\), and SIF\({}_{761}\) has the strongest correlation with IWUE with \(R^{2}\) achieving 0.79 for GPR (Figure 7b), while its performance decreases to 0.71 and 0.46 when it is used to predict IWUE in the morning and midday with using the GPR models (Figure 7b).  
Figure 7: The effect of diurnal observation time on the coefficients of determination (\(R^{2}\)) between inherent water use efficiency (IWUE) and the selected single SIF bands and their combinations by using (**a**) linear regression analysis and (**b**) Gaussian processes regression, respectively. All data have an hourly time resolution. The blue, green, and yellow bars represent \(R^{2}\) for data with observation time at 7–10 a.m., 10 a.m.–15 p.m., and 15–17 p.m., respectively.
## 3 Data and Methodology
### Data Acquisition and Processing
#### 3.2.2 Array Measurements  
Ambient noise was also recorded using an array measurement technique at four potential sites within the city (Figure 2). The measurements were carried out using seven SARA ([[https://www.sara.pg.it/](https://www.sara.pg.it/)]([https://www.sara.pg.it/](https://www.sara.pg.it/)), accessed on 1 March 2025) short-period seismographs distributed over two concentric equilateral triangles with a station in the middle (Figure 2), with each side of the triangle measuring 30 m. The ambient noise was recorded for a period of 40 min at each of the four sites. The acquisition was carried out following SESAME project recommendations. The seven stations were connected to a GPS system in order to homogenize the time base.  
For data processing, only the vertical components of each sensor were considered, discarding the effects of Love waves, which are only present in the horizontal field. Therefore, only Rayleigh waves were considered. The SPAC method was implemented using Geopsy software ([[https://www.geopsy.org/](https://www.geopsy.org/)]([https://www.geopsy.org/](https://www.geopsy.org/)), version 2.10.1). First, the theoretical wavenumberlimits (kmin, kmax) were obtained by introducing the coordinates of each of the seven sensors into the WARANGPS module (from Geopsy package, release 2.10.1) [58]. Then, they were processed using the SPAC toolbox for the definition of the ring parameters. Following the input of the coordinates of each sensor, the software automatically generated spatially distributed sensor pairs, typically comprising 21 pairs derived from seven sensors. Subsequently, the pairs were allocated to one or more rings by defining the inner and outer radii, thereby ensuring optimal pairing. In accordance with the recommendations set forth by [39], each ring should comprise a minimum of two pairs, with the inclusion of as many rings as feasible to enhance resolution. The recorded signals were divided into 50 s windows, which were selected using an anti-triggering algorithm to ensure the maintenance of data quality. Subsequently, spatial autocorrelation curves were calculated for each ring. Spac2 Disp (from Geopsy package, release 2.10.1 [58]) facilitated the visualization of phase velocity histograms based on the calculated autocorrelation values. The final dispersion curve was derived by identifying the Rayleigh wave phase velocity values that significantly contributed to the curve within the defined Kmin and Kmax ranges.
# Dynamic Packet Duplication for Industrial URLLC
## 3 Proposal  
This section describes the proposed solution in order to assess reliability for URLLC communications by using a dynamic packet duplication algorithm based on ML to reduce the resource consumption.
## 1 Introduction
Authors in [18] analyzed the effects of adopting SCFD enabled base stations (BSs) in an OFDM multicell network with the legacy user equipments (UEs). However, they assumed perfect self-interference cancellation, which is currently unrealistic assumption. In [19], the end-to-end capacity of SCFD relaying with two modes: amplify-and-forward and decode-and-forward was investigated. The authors characterized threshold of the self interference below which the full duplex transmission performs better than the half duplex transmission. In their research, they considered an isolated system of three nodes only (i.e., one link of two hops (source-relay-destination)). Authors in [20] developed an optimal dynamic power allocation schemes for different scenarios with an objective of maximizing the sum rate of an SCFD bidirectional link. However, they did not consider the intercell interference. In [21], a single cell full duplex MIMO system was studied. A large number of antennas at the BS were exploited for self interference cancellation. In cellular networks, there are two kinds of wireless full duplex communications: symmetric and asymmetric. In the symmetric full duplex communication, the full duplex transmission takes place between two nodes; they are usually the BS and one UE, and hence it is sometimes called bidirectional FD. On the other hand, the asymmetric full duplex transmission involves three nodes. They are usually BS, downloader UE and uploader UE. In the present research, the problem of intercell interference in multi-cell SCFD wireless systems under the assumption of imperfect cancellation of self interference is investigated. Accordingly, intercell interference control schemes are designed to best satisfy the users, even when their quality of service (QoS) requirements are infeasible. The proposed designs are general in that they are applicable to both kinds of FD: symmetric and asymmetric. The rest of this paper is organized as follows. In Section 2, the model of the full duplex cellular system is developed. In Section 3, we present our proposed game theoretic approach for the best effort service in full duplex cellular system under an infeasible set of target signal-to-interference plus noise ratios (SINRs). Then, the proposed game is analyzed in Section 4. Afterwards, the simulation resultsare shown and discussed in Section 5. Finally, this work is concluded, and possible future directions are presented in Section 6.
# Modeling and Performance Analysis of mmWave and WiFi-Based Vehicle Communications
## 2 System Model  
This section describes the considered V2V communication system model that has been used to compare the performances of mmWaves and Wifi communication systems.  
Usually, 1D and 2D models are used in the literature. However, these models seem to be not realistic enough in a high-traffic environment, when different factors should be taken into account, in order to accurately evaluate the communication performances.  
To further explain this point, we present in Figure 1 2D and 3D models in the context of V2V communications. The scenario consists of transmitter (\(Tx\)) and receiver (\(Rx\)) vehicles communicating with each other, in the presence of a number of obstacle vehicles between them. These vehicles are assumed to be located based on a realistic and reliable Matern Hard Core Process (MHCP) of Type II. The parent's density is denoted by \(\lambda_{v}\), and the minimum distance between each two vehicles is denoted by \(d_{\min}\).  
As shown in Figure 1, the impact of 2D and 3D modeling on line-of-sight (LoS) conditions between \(Tx\) and \(Rx\) is clear. In fact, within the 2-D modeling scenario, the LoS between \(Tx\) and \(Rx\) does not exist. However, within the 3D modeling scenario, some conditions on vehicle heights can be identified, leading to the presence of LoS. Therefore, the 2D modeling approach may overlook the impact of vehicle height on the propagation of electromagnetic waves. Hence, the 3D modeling provides a more accurate representation of the real-world environment, allowing for the inclusion of these factors.  
To further explore the impact of vehicles heights on LoS conditions, different scenarios and conditions, in the considered 3D model of this work, are described and detailed in the next subsections.  
Figure 1: Illustration of a V2V communication example with (**a**) 3D modeling and (**b**) 2D modeling.  
In this model, \(h_{T_{x}}\), \(h_{Rx}\), and \(h_{V}\) denote the heights of the transmitter, the receiver, and the obstacle vehicles, respectively, and \(h_{th}\) is the obstacle vehicles' threshold height, beyond which there is no LoS between the transmitter and the receiver. The different used notations throughout the paper are listed and defined in Table 2.  
Moreover, further details of the considered WiFi and mmWave-based systems, in the context of 2D and 3D modeling, are presented in the following subsections.
## 5 Deployment of PLC for Smart Metering and Smart Grid Systems
### Grid Description
#### 5.1.1 MV and LV PLC Architecture  
Electricity grids in the different areas of the world are fundamentally different [125], but not in their functional principles. Grids are different in aspects related to voltage levels, extension and reach of the MV grid, and consequently, the nature of the LV grid. A good example of this is the difference between the European and North-American model. The European model presents MV grid voltage levels typically ranging from 10 kV to 20 kV, both in overhead and underground distribution. LV grid on each SS covers typically 300 PoS, and distances reach as far as 200 m. MV to LV transformers are usually designed with a \"star\" configuration with 400 V between phases, and 230 V between phase and neutral. North-American model, as a contrast, is usually composed of voltages ranging from 4 kV to 34 kV in MV, and distances ranging from 15 km to 50 km. MV to LV transformers produce voltages of 120 V or 200 V depending on load types. Typical LV cable lengths are close to 300 m, with an average of 10 PoS per transformer. PLC signals may be injected between phase and neutral to 120 V.  
This paper is focused on Smart Metering systems, which are being developed through Europe. It is consequently focused on the European topology. The next sections highlight the most important aspects of the model, under the light of the decisions to be taken for Smart Metering systems with PLC technology [87].
# An Effective Blockchain-Based Defense Model for Organizations against Vishing Attacks
## 3 Preventing Social Engineering Attacks Using Security Principle
### Defenses Based on Split Knowledge Principle
#### 3.1.2 Vishing  
Vishing is a unique assault that falls under the general umbrella of phishing and has the same objectives as phishing. Vishing uses fake phone numbers, voice-altering software, SMS messaging, and SE to deceive consumers into giving critical information that can be utilized for identity theft, financial gain, or account takeover. Voice is commonly used by vishing to mislead users.  
Vishing, unlike phishing, is primarily a telephone-based assault that involves calls to a user's cell phone number. The first step would be for the visher to send a large number of text messages to possible victims from a vast list of phone numbers. The message may instruct users to dial the attacker's phone number. Another vishing technique involves sending a pre-recorded message to potential victims, which is then robo-dialed. To erase accents and develop confidence, it uses computer-generated audio communications. The voice message then leads the user to a human agent who either continues the fraud or asks them to visit an attacker-controlled website. The goal of vishers is to mislead the victims into thinking that they caller has authority by providing social proof [25].  
Educating users helps organizations recognize vishing attacks, which they can then ignore or report. Individuals should never hand out personal information to someone who contacts them via text message or phone call. Those defenses all rely on an individual's accurate judgment; therefore, any error will result in losses for the organization. By applying split knowledge and dual control principles, the victim will not have complete sensitive information, and any suspicious call will be checked; therefore, the damages will be mitigated.
# Quantification of SPECT Concentric Ring Artifacts by Radiomics and Radial Features
## 2 Materials and Methods
### Radiomic Features Extraction  
Texture analysis was performed by two medical physicists ([PERSON] and [PERSON]) on DICOM files of transaxial reconstructions. SPECT image data were imported to MIM software v7 (MIM Software, Inc., Cleveland, OH, USA) [14], where cylindrical volumes of interest (VOIs) were drawn on uniform SPECT sections.VOIs were centered on the middle of a transaxial section individually for each phantom data set. Finally, each dataset, together with its own VOI, was processed by Image Biomarker Standardization Initiative (IBSI) compliant [15] SIBEX software [16]. Following the suggestions of the IBSI before computing features, a pre-processing step was implemented: fixed bin number of 32 and alignment of grid centers were used for intensity discretization and for the interpolation grid, respectively. A total of 163 three-dimensional image texture features were computed (Table 2) and reported in Table S1 of Supplementary Materials.  
Figure 4: Example of images related to the uniform sections and spheres sections of a phantom, which both readers scored “4”, forsevere concentric ring artifacts, in both sections.