esa-sceva/satcom-chunk-collection huggingface dataset:
# Sum Rate Optimization Scheme of UAV-Assisted NOMA under Hardware Impairments
###### Abstract  
In the unmanned aerial vehicle (UAV) assisted non-orthogonal multiple access (NOMA) networks, the practical hardware impairments (HIs) and resource allocation is still a challenging problem. Most existing research on resource allocation algorithms for UAV communication is considered with the ideal hardware condition. However, the impact of HIs on system performance cannot be ignored, especially in the case of high bit rates. Considering the HIs, most studies are from the perspective of performance analysis. The resource allocation of UAV relay-assisted NOMA systems is investigated in this paper with HIs. We aim to maximize the sum rate by jointly optimizing the deployment of UAV and transmit power. To address this problem, we first transformed the mixed integer programming problem (MIPP) into a standard convex optimization problem based on successive convex approximation (SCA) technology. Then, we introduced the Lagrangian dual transformation and quadratic transform methods to solve the power allocation problem. Finally, we propose an effective iterative algorithm to achieve an approximate optimal solution. Numerical results demonstrate that the proposed algorithm achieved better performance in terms of the sum rate compared with other benchmark schemes.  
UAV; NOMA; resource allocation; hardware impairments; quadratic transform
# Wind-Load Response and Evacuation Efficiency Analysis of Marine Evacuation Inflatable Slide
###### Abstract  
Flexible inflatable membrane structure has the characteristics of light weight, large span, and small stiffness, and it is very sensitive to wind load. Aiming at the dynamic response of marine evacuation inflatable slides under complex and changeable wind loads at sea, the response law of the inflatable slide under different wind directions, wind speeds, and internal pressure conditions is studied by using fluid-solid coupling theory. The most dangerous conditions of evacuation system installation and the ideal internal pressure of the inflatable slide meeting the stability requirements are deduced. The LS-DYNA module is used to simulate the inflation process of the slide. The evacuation sliding is rationally simplified. By changing the inflatable internal pressure of the slide, the variation law of displacement, deformation, and sliding speed of the slide is obtained, and the optimal inflation internal pressure satisfying the evacuation efficiency requirement is obtained. The results show that the inflow wind direction angle of 30\({}^{\circ}\) is the most dangerous condition for slideway installation, and the internal pressure of 4000 Pa is the ideal internal pressure to meet the double standards of stability and evacuation efficiency. The numerical results obtained are valuable for analyzing wind resistance of offshore inflatable membrane structures and their practical design and application in evacuation systems.  
marine emergency evacuation equipment; inflatable slide; fluid-solid coupling CFD calculation; ideal internal pressure; simulated slide evacuation +
Footnote †: journal: Applied Sciences
# Sustaining Rice Production through Biofertilization with N\({}_{2}\)-Fixing Cyanobacteria
## 3 Results and Discussion
### Morphological Description of the Cyanobacterial Isolates
G15 formed green colonies on a solid medium and grew uniformly in liquid BG11\({}_{0}\). It showed straight trichomes (41.13 \(\pm\) 1.53 cells per trichome) arranged in parallel and composed by rounded vegetative cells with rounded and conical terminal cells. Intercalary heterocysts were found at a percentage of 4.98 \(\pm\) 0.26 heterocysts per vegetative cell. This strain differentiated akinetes (Figure 4D). Strain G17 was the only component of PG5. This group was most closely related to _Calothrix membranacea_ KLR006. _Calothrix_ sp. is commonly found in cultivated soils, being beneficial for rice growth [31]. G17 formed dark-green colonies on a solid medium and grew with densely packed trichomes, forming rough mats in liquid BG11\({}_{0}\). G17 formed short heteropolar trichomes with an average of 12.47 \(\pm\) 0.59 cells per trichome. Only one terminal heterocyst was found per trichome. Motile hormogonia were easily found in the culture. This strain did not differentiate akinetes (Figure 4E). The combination of morphological and 16S rRNA molecular characterization confirmed the previous taxonomic identification of the cyanobacterial strains and, in the case of strains G04, G10, and G17, provided more detailed information about the closest related strain. It is important to note that the groups PG01, PG02, PG04, and PG05 contain new strains that had not been described before. This is of particular interest regarding their possible use as commercial byproducts or biofertilizers, since their potential had been, thus far, unexplored. Identification of the 16S sequence of new isolated microorganisms is a well-established strategy for the genetic characterization of new strains [32]. However, obtaining the 16S rRNA amplicon from complex samples requires the construction of clone libraries, a process that is tedious and time-consuming [33]. The genetic selection, which has been designed for the purpose of this work, significantly reduces the number of strains to study, saving time and effort in the subsequent morphological and genetic identification of the strains.
# HPoC: A Lightweight Blockchain Consensus Design for the IoT
## 2 Background and Related Work
### Development of Blockchain Consensus  
The problem of consensus mechanisms originated from the distributed database consistency problem in the 1970s and 1980s, and [27] proposed the Two Armies Problem inthe computer field. [PERSON]. [28; 29] proposed the famous Byzantine general problem and the solution algorithm Paxos. [PERSON]. [30] designed the first practical Byzantine problem solution algorithm. Until 2008, the research on consensus mechanisms was limited to the small-scale node database consistency problem; ref. [9] applied a consensus algorithm in a massive-scale open-node network and provided it with a financial currency property, and the research into consensus algorithms has ushered in a rapid development period during the last decade. Successively, PoW, PoS, PoC, DPoS [31], PoE [32], and PoUS [33] were generated. In general, the consensus applied in the existing blockchain technology can be broadly classified into classical consensus and proof-based consensus. Both types of consensus have their advantages and disadvantages: the advantage of classical consensus is that it is fast, but the disadvantages are that it is not fair enough and there is no discussion on the choice of leadership nodes. The advantages of proof-based consensus are that it is decentralized and more democratic, but it consumes corresponding time, power, and financial resources, depending on its type. Thus, a hybrid consensus scheme combining the two kinds of consensus has become a new research direction in recent years. Most of this hybrid consensus uses proof-based consensus to select a certain number of leading nodes from the whole-network nodes, then uses classical consensus to reach a consensus on the block and, finally broadcasts to the whole-network nodes. For example, ref. [34] proposed improving the performance of the PoW protocol by decoupling blockchain operation into two planes: leader election and transaction serialization. Compared with tradition PoS consensus protocols, the BFT-style PoS provides a deterministic finality to guarantee that finalized blocks cannot be revoked. Furthermore, deterministic finality allows for designing a reward-and-punishment strategy to discourage malicious validators from launching attacks, such as double-betting or nothing-at-stake attacks [35; 36]. However, integrating cryptocurrency-oriented blockchain technologies into IoT systems meets tremendous challenges of scalability, storage capacity, security, and privacy. Given the aforementioned difficulties in integrating blockchain technology into IoT systems, building an optimized blockchain with light and efficient consensus algorithms appears to be a prospective solution.
# An Optimized Planning Tool for Microwave Terrestrial and Satellite Link Design
## 3 Tool Description
### Terrestrial Links
#### 3.4.1 Route Selection  
To define the communication path, the Cesium API was used. The API allows the integration of external three-dimensional modules imported using a GL Transmission Format Binary (GLB) file format. The GLB format was used to exhibit the 3D models, as it represents a binary structure of the data included in GL Transmission Format (gITF) files, using JavaScript Object Notation (JSON). The Blender software, which enables the development of 3D models and the export of these models using the GLB file format, was used to build the GLB file for the antennas.  
In order to track user clicks on the Cesium window, Cesium offers an internal window listener. Using the camera position and projection, it is possible to store and interpret the user's click location for a true place in the scene. After clicking the window, the user can distinguish between the components of the communication system by label and a 3D representation of an antenna placed on the spot they had chosen.  
The path length and other measurements needed for calculations were taken straight from the Cesium API, as Cesium offers a 1:1 measurement of length in comparison to the real world.  
If both the transmission and receiving antennas are in place, the first Fresnel Ellipsoid is represented between both antennas, as depicted in Figure 3. This ellipsoid provides an estimate of the path through which the signal energy travels. For the ellipsoid to be presented correctly, it is placed in the middle point between the path origin and the target and rotated using the Eye-Gaze-Up representation [18].  
Similar to how a station antenna is integrated into a communication system, so is a passive repeater. A passive repeater model is positioned once the user selects the inclusion of a passive repeater and specifies the location where it is to be placed. The orientation where the passive repeater is placed reflects the angle where the post-reflection signal can be found in the receiving antenna.
## 4 Results
### PSInSAR Data Refinement and Quality  
The raw output from PSInSAR processing required substantial refinement (Section 3.4) to ensure accuracy for VUG analysis. Figure 7 illustrates the effectiveness of our data cleaning and processing steps, comparing the mean heights across all stacks before and after addressing inconsistencies (like missing points and noise) and performing the grid-based maximum height extraction. The initial irregular mean heights were influenced by fluctuations in detectable PS points between stacks, the inclusion of noise (including erroneous negative values), and the inherent diversity of PS point elevations ranging from building bases to tops. The processed data (blue bars) show a significantly smoother and more plausible trend in mean height across the stacks, demonstrating the robustness of our post-processing methodology in generating more reliable height estimations suitable for analyzing high artificial structures.  
Figure 7 illustrates the effectiveness of our data cleaning and processing steps, comparing the mean heights across all stacks before and after addressing inconsistencies and noise. The processed data show a significant improvement in height estimation, demonstrating the robustness of our methodology.  
The figure highlights the initial irregular mean heights, influenced by the fluctuation in PS points, the inclusion of noisy points (including negative values), and the diversity of point elevations ranging from the building base to the top. Our post-processing steps, which involve extracting the maximum value within each grid and the median within the grids, provide a more accurate analysis of high artificial structures compared to the raw data.  
Furthermore, Figure 8 illustrates how post-processing transforms the sparse PS point data into a more usable, gridded format (50-m grids) for comparison with validation data (obtained by drone). Extracting accurate height information directly from the raw PS points (pre-processing) was challenging due to noise and scatter. Post-processing, including outlier removal and maximum value extraction within grids, makes it easier to discern representative heights for comparison and time-series analysis, although some residual noise can still affect measurements.
# Extracting Crop Spatial Distribution from Gaofen 2 Imagery Using a Convolutional Neural Network
###### Abstract  
Using satellite remote sensing has become a mainstream approach for extracting crop spatial distribution. Making edges finer is a challenge, while simultaneously extracting crop spatial distribution information from high-resolution remote sensing images using a convolutional neural network (CNN). Based on the characteristics of the crop area in the Gaofen 2 (GF-2) images, this paper proposes an improved CNN to extract fine crop areas. The CNN comprises a feature extractor and a classifier. The feature extractor employs a spectral feature extraction unit to generate spectral features, and five coding-decoding-pair units to generate five level features. A linear model is used to fuse features of different levels, and the fusion results are up-sampled to obtain a feature map consistent with the structure of the input image. This feature map is used by the classifier to perform pixel-by-pixel classification. In this study, the SegNet and RefineNet models and 21 GF-2 images of Feicheng County, Shandong Province, China, were chosen for comparison experiment. Our approach had an accuracy of 93.26%, which is higher than those of the existing SegNet (78.12%) and RefineNet (86.54%) models. This demonstrates the superiority of the proposed method in extracting crop spatial distribution information from GF-2 remote sensing images.  
Keywords:convolutional neural network; high-resolution remote sensing imagery; Gaofen 2 imagery; crops; winter wheat; spatial distribution information; Feicheng county +
Footnote †: journal: Medical Image Analysis
## 2 Related Work
These methods aim to achieve model training and information sharing among participants while preserving the privacy of user data. In the field of verifiable privacy-preserving federated learning, researchers have innovated diverse methods to ensure data confidentiality and collaborative model training. [PERSON] et al. [17] uses a dual-mask protocol for gradient privacy, requiring servers to prove aggregated results' accuracy. [PERSON] et al. [18] substitutes homomorphic hashing for dual masks in challenge creation. [PERSON] et al. [19] designed a specialized interactive proof protocol using arithmetic circuits to detect malicious servers. This method ensures that the server cannot tamper with users' data or models during the federated learning process. [PERSON] et al. [20] utilized trusted execution environments such as SGX (Software Guard Extensions) and TrustZone to achieve privacy preserving and execution verification. These trusted execution environments ensure that the computation processes running on servers are secure and users' privacy data remain confidential. [PERSON] et al. [21] applied Lagrange interpolation and blinding techniques for enhanced privacy and gradient verification. Each approach uniquely contributes to the evolving landscape of privacy in federated learning, showcasing varied strategies to tackle privacy concerns in collaborative machine learning settings. All of these studies and frameworks promote the development of federated learning techniques while protecting privacy, providing powerful methods and guarantees to protect user data privacy. The introduction of homomorphic encryption and differential privacy allows for better protection of individual users' private information during federated learning, realizes cooperative computation and model training while maintaining data privacy, and enables cooperative computation and model training across devices to be performed more reliably.
# Efficient Seismic Fragility Analysis for Large-Scale Piping System Utilizing Bayesian Approach
## 6 Summary and Conclusions  
In this study, a method for efficiently estimating the seismic fragility of the piping system was presented. Specifically, based on the existing EPRI SOV seismic fragility analysis method, we proposed an approach to calculate the piping seismic fragility curve using the concept of Bayesian inference. This method acquires the prior piping seismic fragility curve through the EPRI SOV method and minimizes the numerical cost of nonlinear seismic response analyses required for the accurate seismic fragility curve calculation using the obtained prior probability distribution and Bayesian updating concept. Ultimately, this approach creates an efficient process of performing the piping seismic fragility calculation that reduces the cost of calculating the required nonlinear seismic response analyses compared to the conventional IDA-based MLE method, while maintaining the accuracy of the fragility results.  
Figure 11: Piping seismic fragility curve regarding a limit state of seismically vulnerable T-joint T125.  
Figure 12: Piping seismic fragility curve regarding a limit state of seismically vulnerable T-joint T135.  
In order to verify the validity of the proposed method, piping seismic fragility curves were calculated by applying the proposed method to the example of the building-piping coupled structural system. The consideration of the damping ratio for the coupled structural model was done by constituting the non-classical damping matrix because the damping ratios of each subsystem are different from each other. Such a non-classical damping matrix was considered in the process of the earthquake time history analyses. Specifically, the piping seismic fragility curve results to which the proposed method was applied were compared with the results of the existing IDA-based MLE method and were analyzed in terms of accuracy and efficiency. As a result, the method proposed in this study showed similar accuracy compared with the existing method regarding the final seismic fragility results, but it reduced the numerical cost of nonlinear seismic response analyses. Therefore, the method proposed in this study and related research results can be judged as being an effective method for analyzing the seismic fragility of large piping systems in the future.  
Conceptualization, S.K., Y.R., and B.-S.J.; methodology, S.K., Y.R., and B.-S.J.; validation, S.K., Y.R., and B.-S.J.; formal analysis, S.K., Y.R., and B.-S.J.; data curation, S.K., Y.R., and B.-S.J.; writing: original draft preparation, S.K., Y.R., and B.-S.J.; writing: review and editing, S.K., Y.R., and B.-S.J. All authors have read and agreed to the published version of the manuscript.  
The first author gratefully acknowledges support by the research fund of Hanbat National University in 2019. This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science, ICT & Future Planning) (NRF-2017R1C1B1002855).  
The authors declare no conflict of interest.
###### Abstract  
The synchronization of time between devices is one of the more important and challenging problems in wireless networks. We discuss the problem of maximization of the probability of receiving a message from a device using a limited listening time window to minimize energy utilization. We propose a solution to two important problems in wireless networks of battery-powered devices: a method of establishing a connection with a device that has been disconnected from the system for a long time and developed unknown skew and also two approaches to follow-up clock synchronization using the confidence interval method. We start with the analysis of measurements of clock skew. The algorithms are evaluated using extensive simulations and we discuss the selection of parameters balancing between minimizing the energy utilization and maximizing the probability of reception of the message. We show that the selection of a time window of growing size requires less energy to receive a packet than using the same size of time window repeated multiple times. The shifting of reception windows can further decrease the energy cost if lower packet reception probability is acceptable. We also propose and evaluate an algorithm scaling the reception window size to the interval between the packet transmission.  
LP WAN; LoRa; clock synchronization; time skew +
Footnote †: journal: Sensors
# Remote Sensing Road Extraction by Road Segmentation Network
## 3 Experiments
Additional examples of road extraction are shown in Figure 4. It is obvious from the subgraph (c,e) that road connectivity could not be restored by FCN [19], UNet [20], and ResUNet [22]. The results of CasNet [21] and the DinkNet [23] missed segments on subgraph (f) compared with our proposed method. In the subgraph (a,b), the edge pixels of the trunk road were extracted completely by the proposed method. These examples demonstrate the effectiveness of our proposed method on road extraction.
## 3 Materials and Methods
### In Situ Monitoring Network  
In February 2020, two fixed stations for real-time turbidity monitoring were installed at 2 m depth at the two sides of the artificial island in the Treporti and San Nicolo channels (brown dots in Figure 1). Each station is equipped with an OBS501 turbidity meter (Campbell Scientific, Loughborough, UK) with an integrated antifouling system, which acquires data every 10 min.  
Water flow was available from continuous acquisitions of two upward-looking acoustic Doppler current profilers (600 KHz RDI Workhorse Monitor ADCP; Teledyne RD Instruments, San Diego, CA, USA) deployed at the bottom of the inlet channels (red dots in Figure 1), which recorded current velocity and direction and acoustic backscatter along the water column with a 5 min sampling interval and a 0.35 m vertical cell size. Blanking ranges at bottom and surface were excluded from the analysis (2 and 2.5 m, respectively).
# Optimized Gateway Placement for Interference Cancellation in Transmit-Only LPWA Networks
## 5 Numerical and Simulation Results
### Comparison of the WBG and PGL Algorithm  
In this section, we compare the two algorithms in terms of average contention for different pixel densities. Assume 3-10 SNs are placed at random in a \(20\times 20\) m\({}^{2}\) network area. The average contention by two algorithms of WBG and PGL are shown in Figure 11. There are \(100\times 100\) pixels in Figure 11a and \(1000\times 1000\) pixels in Figure 11b. It is obvious that, as the pixel density is increased, the performance of the PGL algorithm approaches that of the WBG algorithm. In other words, the average contention of algorithms PGL and WBG, in the same network deployment space, will be more consistent, with more pixels at the same number of SNs and GWs. Therefore, the algorithm of PGL could have the enough accuracy for optimum location of GWs with enough pixels. We observe that PGL achieved a lower average contention for eight SNs with \(100\times 100\) pixels compared to \(1000\times 1000\) pixels. We attribute that aberration to the well-known fact that the greedy algorithm is not globally optimum and that the \(100\times 100\) locations may not have been a subset of the \(1000\times 1000\) locations.